zig/src/translate_c.zig

6682 lines
263 KiB
Zig

const std = @import("std");
const testing = std.testing;
const assert = std.debug.assert;
const mem = std.mem;
const math = std.math;
const meta = std.meta;
const clang = @import("clang.zig");
const aro = @import("aro");
const CToken = aro.Tokenizer.Token;
const common = @import("aro_translate_c");
const ast = common.ast;
const Node = ast.Node;
const Tag = Node.Tag;
const Error = common.Error;
const MacroProcessingError = common.MacroProcessingError;
const TypeError = common.TypeError;
const TransError = common.TransError;
const SymbolTable = common.SymbolTable;
const AliasList = common.AliasList;
const ResultUsed = common.ResultUsed;
const Scope = common.ScopeExtra(Context, clang.QualType);
const PatternList = common.PatternList;
const MacroSlicer = common.MacroSlicer;
pub const Context = struct {
gpa: mem.Allocator,
arena: mem.Allocator,
source_manager: *clang.SourceManager,
decl_table: std.AutoArrayHashMapUnmanaged(usize, []const u8) = .empty,
alias_list: AliasList,
global_scope: *Scope.Root,
clang_context: *clang.ASTContext,
mangle_count: u32 = 0,
/// Table of record decls that have been demoted to opaques.
opaque_demotes: std.AutoHashMapUnmanaged(usize, void) = .empty,
/// Table of unnamed enums and records that are child types of typedefs.
unnamed_typedefs: std.AutoHashMapUnmanaged(usize, []const u8) = .empty,
/// Needed to decide if we are parsing a typename
typedefs: std.StringArrayHashMapUnmanaged(void) = .empty,
/// This one is different than the root scope's name table. This contains
/// a list of names that we found by visiting all the top level decls without
/// translating them. The other maps are updated as we translate; this one is updated
/// up front in a pre-processing step.
global_names: std.StringArrayHashMapUnmanaged(void) = .empty,
/// This is similar to `global_names`, but contains names which we would
/// *like* to use, but do not strictly *have* to if they are unavailable.
/// These are relevant to types, which ideally we would name like
/// 'struct_foo' with an alias 'foo', but if either of those names is taken,
/// may be mangled.
/// This is distinct from `global_names` so we can detect at a type
/// declaration whether or not the name is available.
weak_global_names: std.StringArrayHashMapUnmanaged(void) = .empty,
pattern_list: PatternList,
fn getMangle(c: *Context) u32 {
c.mangle_count += 1;
return c.mangle_count;
}
/// Convert a null-terminated C string to a slice allocated in the arena
fn str(c: *Context, s: [*:0]const u8) ![]u8 {
return c.arena.dupe(u8, mem.sliceTo(s, 0));
}
/// Convert a clang source location to a file:line:column string
fn locStr(c: *Context, loc: clang.SourceLocation) ![]u8 {
const spelling_loc = c.source_manager.getSpellingLoc(loc);
const filename_c = c.source_manager.getFilename(spelling_loc);
const filename = if (filename_c) |s| try c.str(s) else @as([]const u8, "(no file)");
const line = c.source_manager.getSpellingLineNumber(spelling_loc);
const column = c.source_manager.getSpellingColumnNumber(spelling_loc);
return std.fmt.allocPrint(c.arena, "{s}:{d}:{d}", .{ filename, line, column });
}
};
pub fn translate(
gpa: mem.Allocator,
args_begin: [*]?[*:0]const u8,
args_end: [*]?[*:0]const u8,
errors: *std.zig.ErrorBundle,
resources_path: [*:0]const u8,
) !std.zig.Ast {
var clang_errors: []clang.ErrorMsg = &.{};
const ast_unit = clang.LoadFromCommandLine(
args_begin,
args_end,
&clang_errors.ptr,
&clang_errors.len,
resources_path,
) orelse {
defer clang.ErrorMsg.delete(clang_errors.ptr, clang_errors.len);
var bundle: std.zig.ErrorBundle.Wip = undefined;
try bundle.init(gpa);
defer bundle.deinit();
for (clang_errors) |c_error| {
const line = line: {
const source = c_error.source orelse break :line 0;
var start = c_error.offset;
while (start > 0) : (start -= 1) {
if (source[start - 1] == '\n') break;
}
var end = c_error.offset;
while (true) : (end += 1) {
if (source[end] == 0) break;
if (source[end] == '\n') break;
}
break :line try bundle.addString(source[start..end]);
};
try bundle.addRootErrorMessage(.{
.msg = try bundle.addString(c_error.msg_ptr[0..c_error.msg_len]),
.src_loc = if (c_error.filename_ptr) |filename_ptr| try bundle.addSourceLocation(.{
.src_path = try bundle.addString(filename_ptr[0..c_error.filename_len]),
.span_start = c_error.offset,
.span_main = c_error.offset,
.span_end = c_error.offset + 1,
.line = c_error.line,
.column = c_error.column,
.source_line = line,
}) else .none,
});
}
errors.* = try bundle.toOwnedBundle("");
return error.SemanticAnalyzeFail;
};
defer ast_unit.delete();
// For memory that has the same lifetime as the Ast that we return
// from this function.
var arena_allocator = std.heap.ArenaAllocator.init(gpa);
defer arena_allocator.deinit();
const arena = arena_allocator.allocator();
var context = Context{
.gpa = gpa,
.arena = arena,
.source_manager = ast_unit.getSourceManager(),
.alias_list = AliasList.init(gpa),
.global_scope = try arena.create(Scope.Root),
.clang_context = ast_unit.getASTContext(),
.pattern_list = try PatternList.init(gpa),
};
context.global_scope.* = Scope.Root.init(&context);
defer {
context.decl_table.deinit(gpa);
context.alias_list.deinit();
context.global_names.deinit(gpa);
context.opaque_demotes.deinit(gpa);
context.unnamed_typedefs.deinit(gpa);
context.typedefs.deinit(gpa);
context.global_scope.deinit();
context.pattern_list.deinit(gpa);
}
@setEvalBranchQuota(2000);
inline for (@typeInfo(std.zig.c_builtins).@"struct".decls) |decl| {
const builtin = try Tag.pub_var_simple.create(arena, .{
.name = decl.name,
.init = try Tag.import_c_builtin.create(arena, decl.name),
});
try addTopLevelDecl(&context, decl.name, builtin);
}
try prepopulateGlobalNameTable(ast_unit, &context);
if (!ast_unit.visitLocalTopLevelDecls(&context, declVisitorC)) {
return error.OutOfMemory;
}
try transPreprocessorEntities(&context, ast_unit);
for (context.alias_list.items) |alias| {
const node = try Tag.alias.create(arena, .{ .actual = alias.alias, .mangled = alias.name });
try addTopLevelDecl(&context, alias.alias, node);
}
return ast.render(gpa, context.global_scope.nodes.items);
}
/// Determines whether macro is of the form: `#define FOO FOO` (Possibly with trailing tokens)
/// Macros of this form will not be translated.
fn isSelfDefinedMacro(unit: *const clang.ASTUnit, c: *const Context, macro: *const clang.MacroDefinitionRecord) !bool {
const source = try getMacroText(unit, c, macro);
var tokenizer: aro.Tokenizer = .{
.buf = source,
.source = .unused,
.langopts = .{},
};
const name_tok = tokenizer.nextNoWS();
const name = source[name_tok.start..name_tok.end];
const first_tok = tokenizer.nextNoWS();
// We do not just check for `.Identifier` below because keyword tokens are preferentially matched first by
// the tokenizer.
// In other words we would miss `#define inline inline` (`inline` is a valid c89 identifier)
if (first_tok.id == .eof) return false;
return mem.eql(u8, name, source[first_tok.start..first_tok.end]);
}
fn prepopulateGlobalNameTable(ast_unit: *clang.ASTUnit, c: *Context) !void {
if (!ast_unit.visitLocalTopLevelDecls(c, declVisitorNamesOnlyC)) {
return error.OutOfMemory;
}
// TODO if we see #undef, delete it from the table
var it = ast_unit.getLocalPreprocessingEntities_begin();
const it_end = ast_unit.getLocalPreprocessingEntities_end();
while (it.I != it_end.I) : (it.I += 1) {
const entity = it.deref();
switch (entity.getKind()) {
.MacroDefinitionKind => {
const macro = @as(*clang.MacroDefinitionRecord, @ptrCast(entity));
const raw_name = macro.getName_getNameStart();
const name = try c.str(raw_name);
if (!try isSelfDefinedMacro(ast_unit, c, macro)) {
try c.global_names.put(c.gpa, name, {});
}
},
else => {},
}
}
}
fn declVisitorNamesOnlyC(context: ?*anyopaque, decl: *const clang.Decl) callconv(.c) bool {
const c: *Context = @ptrCast(@alignCast(context));
declVisitorNamesOnly(c, decl) catch return false;
return true;
}
fn declVisitorC(context: ?*anyopaque, decl: *const clang.Decl) callconv(.c) bool {
const c: *Context = @ptrCast(@alignCast(context));
declVisitor(c, decl) catch return false;
return true;
}
fn declVisitorNamesOnly(c: *Context, decl: *const clang.Decl) Error!void {
if (decl.castToNamedDecl()) |named_decl| {
const decl_name = try c.str(named_decl.getName_bytes_begin());
switch (decl.getKind()) {
.Record, .Enum => {
// These types are prefixed with the container kind.
const container_prefix = if (decl.getKind() == .Record) prefix: {
const record_decl: *const clang.RecordDecl = @ptrCast(decl);
if (record_decl.isUnion()) {
break :prefix "union";
} else {
break :prefix "struct";
}
} else "enum";
const prefixed_name = try std.fmt.allocPrint(c.arena, "{s}_{s}", .{ container_prefix, decl_name });
// `decl_name` and `prefixed_name` are the preferred names for this type.
// However, we can name it anything else if necessary, so these are "weak names".
try c.weak_global_names.ensureUnusedCapacity(c.gpa, 2);
c.weak_global_names.putAssumeCapacity(decl_name, {});
c.weak_global_names.putAssumeCapacity(prefixed_name, {});
},
else => {
try c.global_names.put(c.gpa, decl_name, {});
},
}
// Check for typedefs with unnamed enum/record child types.
if (decl.getKind() == .Typedef) {
const typedef_decl = @as(*const clang.TypedefNameDecl, @ptrCast(decl));
var child_ty = typedef_decl.getUnderlyingType().getTypePtr();
const addr: usize = while (true) switch (child_ty.getTypeClass()) {
.Enum => {
const enum_ty = @as(*const clang.EnumType, @ptrCast(child_ty));
const enum_decl = enum_ty.getDecl();
// check if this decl is unnamed
if (@as(*const clang.NamedDecl, @ptrCast(enum_decl)).getName_bytes_begin()[0] != 0) return;
break @intFromPtr(enum_decl.getCanonicalDecl());
},
.Record => {
const record_ty = @as(*const clang.RecordType, @ptrCast(child_ty));
const record_decl = record_ty.getDecl();
// check if this decl is unnamed
if (@as(*const clang.NamedDecl, @ptrCast(record_decl)).getName_bytes_begin()[0] != 0) return;
break @intFromPtr(record_decl.getCanonicalDecl());
},
.Elaborated => {
const elaborated_ty = @as(*const clang.ElaboratedType, @ptrCast(child_ty));
child_ty = elaborated_ty.getNamedType().getTypePtr();
},
.Decayed => {
const decayed_ty = @as(*const clang.DecayedType, @ptrCast(child_ty));
child_ty = decayed_ty.getDecayedType().getTypePtr();
},
.Attributed => {
const attributed_ty = @as(*const clang.AttributedType, @ptrCast(child_ty));
child_ty = attributed_ty.getEquivalentType().getTypePtr();
},
.MacroQualified => {
const macroqualified_ty = @as(*const clang.MacroQualifiedType, @ptrCast(child_ty));
child_ty = macroqualified_ty.getModifiedType().getTypePtr();
},
else => return,
};
const result = try c.unnamed_typedefs.getOrPut(c.gpa, addr);
if (result.found_existing) {
// One typedef can declare multiple names.
// Don't put this one in `decl_table` so it's processed later.
return;
}
result.value_ptr.* = decl_name;
// Put this typedef in the decl_table to avoid redefinitions.
try c.decl_table.putNoClobber(c.gpa, @intFromPtr(typedef_decl.getCanonicalDecl()), decl_name);
try c.typedefs.put(c.gpa, decl_name, {});
}
}
}
fn declVisitor(c: *Context, decl: *const clang.Decl) Error!void {
switch (decl.getKind()) {
.Function => {
return transFnDecl(c, &c.global_scope.base, @as(*const clang.FunctionDecl, @ptrCast(decl)));
},
.Typedef => {
try transTypeDef(c, &c.global_scope.base, @as(*const clang.TypedefNameDecl, @ptrCast(decl)));
},
.Enum => {
try transEnumDecl(c, &c.global_scope.base, @as(*const clang.EnumDecl, @ptrCast(decl)));
},
.Record => {
try transRecordDecl(c, &c.global_scope.base, @as(*const clang.RecordDecl, @ptrCast(decl)));
},
.Var => {
return visitVarDecl(c, @as(*const clang.VarDecl, @ptrCast(decl)), null);
},
.Empty => {
// Do nothing
},
.FileScopeAsm => {
try transFileScopeAsm(c, &c.global_scope.base, @as(*const clang.FileScopeAsmDecl, @ptrCast(decl)));
},
else => {
const decl_name = try c.str(decl.getDeclKindName());
try warn(c, &c.global_scope.base, decl.getLocation(), "ignoring {s} declaration", .{decl_name});
},
}
}
fn transFileScopeAsm(c: *Context, scope: *Scope, file_scope_asm: *const clang.FileScopeAsmDecl) Error!void {
const asm_string = file_scope_asm.getAsmString();
var len: usize = undefined;
const bytes_ptr = asm_string.getString_bytes_begin_size(&len);
const str = try std.fmt.allocPrint(c.arena, "\"{f}\"", .{std.zig.fmtString(bytes_ptr[0..len])});
const str_node = try Tag.string_literal.create(c.arena, str);
const asm_node = try Tag.asm_simple.create(c.arena, str_node);
const block = try Tag.block_single.create(c.arena, asm_node);
const comptime_node = try Tag.@"comptime".create(c.arena, block);
try scope.appendNode(comptime_node);
}
fn transFnDecl(c: *Context, scope: *Scope, fn_decl: *const clang.FunctionDecl) Error!void {
const fn_name = try c.str(@as(*const clang.NamedDecl, @ptrCast(fn_decl)).getName_bytes_begin());
if (c.global_scope.sym_table.contains(fn_name))
return; // Avoid processing this decl twice
// Skip this declaration if a proper definition exists
if (!fn_decl.isThisDeclarationADefinition()) {
if (fn_decl.getDefinition()) |def|
return transFnDecl(c, scope, def);
}
const fn_decl_loc = fn_decl.getLocation();
const has_body = fn_decl.hasBody();
const storage_class = fn_decl.getStorageClass();
const is_always_inline = has_body and fn_decl.hasAlwaysInlineAttr();
var decl_ctx = FnDeclContext{
.fn_name = fn_name,
.has_body = has_body,
.storage_class = storage_class,
.is_always_inline = is_always_inline,
.is_export = switch (storage_class) {
.None => has_body and !is_always_inline and !fn_decl.isInlineSpecified(),
.Extern, .Static => false,
.PrivateExtern => return failDecl(c, fn_decl_loc, fn_name, "unsupported storage class: private extern", .{}),
.Auto => unreachable, // Not legal on functions
.Register => unreachable, // Not legal on functions
},
};
var fn_qt = fn_decl.getType();
const fn_type = while (true) {
const fn_type = fn_qt.getTypePtr();
switch (fn_type.getTypeClass()) {
.Attributed => {
const attr_type: *const clang.AttributedType = @ptrCast(fn_type);
fn_qt = attr_type.getEquivalentType();
},
.Paren => {
const paren_type: *const clang.ParenType = @ptrCast(fn_type);
fn_qt = paren_type.getInnerType();
},
.MacroQualified => {
const macroqualified_ty: *const clang.MacroQualifiedType = @ptrCast(fn_type);
fn_qt = macroqualified_ty.getModifiedType();
},
else => break fn_type,
}
};
const fn_ty: *const clang.FunctionType = @ptrCast(fn_type);
const return_qt = fn_ty.getReturnType();
const proto_node = switch (fn_type.getTypeClass()) {
.FunctionProto => blk: {
const fn_proto_type: *const clang.FunctionProtoType = @ptrCast(fn_type);
if (has_body and fn_proto_type.isVariadic()) {
decl_ctx.has_body = false;
decl_ctx.storage_class = .Extern;
decl_ctx.is_export = false;
decl_ctx.is_always_inline = false;
try warn(c, &c.global_scope.base, fn_decl_loc, "TODO unable to translate variadic function, demoted to extern", .{});
}
break :blk transFnProto(c, fn_decl, fn_proto_type, fn_decl_loc, decl_ctx, true) catch |err| switch (err) {
error.UnsupportedType => {
return failDecl(c, fn_decl_loc, fn_name, "unable to resolve prototype of function", .{});
},
error.OutOfMemory => |e| return e,
};
},
.FunctionNoProto => blk: {
const fn_no_proto_type: *const clang.FunctionType = @ptrCast(fn_type);
break :blk transFnNoProto(c, fn_no_proto_type, fn_decl_loc, decl_ctx, true) catch |err| switch (err) {
error.UnsupportedType => {
return failDecl(c, fn_decl_loc, fn_name, "unable to resolve prototype of function", .{});
},
error.OutOfMemory => |e| return e,
};
},
else => return failDecl(c, fn_decl_loc, fn_name, "unable to resolve function type {}", .{fn_type.getTypeClass()}),
};
if (!decl_ctx.has_body) {
if (scope.id != .root) {
return addLocalExternFnDecl(c, scope, fn_name, Node.initPayload(&proto_node.base));
}
return addTopLevelDecl(c, fn_name, Node.initPayload(&proto_node.base));
}
// actual function definition with body
const body_stmt = fn_decl.getBody();
var block_scope = try Scope.Block.init(c, &c.global_scope.base, false);
block_scope.return_type = return_qt;
defer block_scope.deinit();
const top_scope = &block_scope.base;
var param_id: c_uint = 0;
for (proto_node.data.params) |*param| {
const param_name = param.name orelse {
proto_node.data.is_extern = true;
proto_node.data.is_export = false;
proto_node.data.is_inline = false;
try warn(c, &c.global_scope.base, fn_decl_loc, "function {s} parameter has no name, demoted to extern", .{fn_name});
return addTopLevelDecl(c, fn_name, Node.initPayload(&proto_node.base));
};
const c_param = fn_decl.getParamDecl(param_id);
const qual_type = c_param.getOriginalType();
const is_const = qual_type.isConstQualified();
const mangled_param_name = try block_scope.makeMangledName(c, param_name);
param.name = mangled_param_name;
if (!is_const) {
const bare_arg_name = try std.fmt.allocPrint(c.arena, "arg_{s}", .{mangled_param_name});
const arg_name = try block_scope.makeMangledName(c, bare_arg_name);
param.name = arg_name;
const redecl_node = try Tag.arg_redecl.create(c.arena, .{ .actual = mangled_param_name, .mangled = arg_name });
try block_scope.statements.append(redecl_node);
}
try block_scope.discardVariable(c, mangled_param_name);
param_id += 1;
}
const casted_body: *const clang.CompoundStmt = @ptrCast(body_stmt);
transCompoundStmtInline(c, casted_body, &block_scope) catch |err| switch (err) {
error.OutOfMemory => |e| return e,
error.UnsupportedTranslation,
error.UnsupportedType,
=> {
proto_node.data.is_extern = true;
proto_node.data.is_export = false;
proto_node.data.is_inline = false;
try warn(c, &c.global_scope.base, fn_decl_loc, "unable to translate function, demoted to extern", .{});
return addTopLevelDecl(c, fn_name, Node.initPayload(&proto_node.base));
},
};
// add return statement if the function didn't have one
blk: {
const maybe_body = try block_scope.complete(c);
if (fn_ty.getNoReturnAttr() or isAnyopaque(return_qt) or maybe_body.isNoreturn(false)) {
proto_node.data.body = maybe_body;
break :blk;
}
const rhs = transZeroInitExpr(c, top_scope, fn_decl_loc, return_qt.getTypePtr()) catch |err| switch (err) {
error.OutOfMemory => |e| return e,
error.UnsupportedTranslation,
error.UnsupportedType,
=> {
proto_node.data.is_extern = true;
proto_node.data.is_export = false;
proto_node.data.is_inline = false;
try warn(c, &c.global_scope.base, fn_decl_loc, "unable to create a return value for function, demoted to extern", .{});
return addTopLevelDecl(c, fn_name, Node.initPayload(&proto_node.base));
},
};
const ret = try Tag.@"return".create(c.arena, rhs);
try block_scope.statements.append(ret);
proto_node.data.body = try block_scope.complete(c);
}
return addTopLevelDecl(c, fn_name, Node.initPayload(&proto_node.base));
}
fn transQualTypeMaybeInitialized(c: *Context, scope: *Scope, qt: clang.QualType, decl_init: ?*const clang.Expr, loc: clang.SourceLocation) TransError!Node {
return if (decl_init) |init_expr|
transQualTypeInitialized(c, scope, qt, init_expr, loc)
else
transQualType(c, scope, qt, loc);
}
/// This is used in global scope to convert a string literal `S` to [*c]u8:
/// &(struct {
/// var static = S.*;
/// }).static;
fn stringLiteralToCharStar(c: *Context, str: Node) Error!Node {
const var_name = Scope.Block.static_inner_name;
const variables = try c.arena.alloc(Node, 1);
variables[0] = try Tag.mut_str.create(c.arena, .{ .name = var_name, .init = str });
const anon_struct = try Tag.@"struct".create(c.arena, .{
.layout = .none,
.fields = &.{},
.functions = &.{},
.variables = variables,
});
const member_access = try Tag.field_access.create(c.arena, .{
.lhs = anon_struct,
.field_name = var_name,
});
return Tag.address_of.create(c.arena, member_access);
}
/// if mangled_name is not null, this var decl was declared in a block scope.
fn visitVarDecl(c: *Context, var_decl: *const clang.VarDecl, mangled_name: ?[]const u8) Error!void {
const var_name = mangled_name orelse try c.str(@as(*const clang.NamedDecl, @ptrCast(var_decl)).getName_bytes_begin());
if (c.global_scope.sym_table.contains(var_name))
return; // Avoid processing this decl twice
const is_pub = mangled_name == null;
const is_threadlocal = var_decl.getTLSKind() != .None;
const scope = &c.global_scope.base;
const var_decl_loc = var_decl.getLocation();
const qual_type = var_decl.getTypeSourceInfo_getType();
const storage_class = var_decl.getStorageClass();
const has_init = var_decl.hasInit();
const decl_init = var_decl.getInit();
var is_const = qual_type.isConstQualified();
// In C extern variables with initializers behave like Zig exports.
// extern int foo = 2;
// does the same as:
// extern int foo;
// int foo = 2;
var is_extern = storage_class == .Extern and !has_init;
var is_export = !is_extern and storage_class != .Static;
if (!is_extern and qualTypeWasDemotedToOpaque(c, qual_type)) {
return failDecl(c, var_decl_loc, var_name, "non-extern variable has opaque type", .{});
}
const type_node = transQualTypeMaybeInitialized(c, scope, qual_type, decl_init, var_decl_loc) catch |err| switch (err) {
error.UnsupportedTranslation, error.UnsupportedType => {
return failDecl(c, var_decl_loc, var_name, "unable to resolve variable type", .{});
},
error.OutOfMemory => |e| return e,
};
var init_node: ?Node = null;
// If the initialization expression is not present, initialize with undefined.
// If it is an integer literal, we can skip the @as since it will be redundant
// with the variable type.
if (has_init) trans_init: {
if (decl_init) |expr| {
const node_or_error = if (expr.getStmtClass() == .StringLiteralClass)
transStringLiteralInitializer(c, @as(*const clang.StringLiteral, @ptrCast(expr)), type_node)
else
transExprCoercing(c, scope, expr, .used);
init_node = node_or_error catch |err| switch (err) {
error.UnsupportedTranslation,
error.UnsupportedType,
=> {
is_extern = true;
is_export = false;
try warn(c, scope, var_decl_loc, "unable to translate variable initializer, demoted to extern", .{});
break :trans_init;
},
error.OutOfMemory => |e| return e,
};
if (!qualTypeIsBoolean(qual_type) and isBoolRes(init_node.?)) {
init_node = try Tag.int_from_bool.create(c.arena, init_node.?);
} else if (init_node.?.tag() == .string_literal and qualTypeIsCharStar(qual_type)) {
init_node = try stringLiteralToCharStar(c, init_node.?);
}
} else {
init_node = Tag.undefined_literal.init();
}
} else if (storage_class != .Extern) {
// The C language specification states that variables with static or threadlocal
// storage without an initializer are initialized to a zero value.
// std.mem.zeroes(T)
init_node = try Tag.std_mem_zeroes.create(c.arena, type_node);
} else if (qual_type.getTypeClass() == .IncompleteArray) {
// Oh no, an extern array of unknown size! These are really fun because there's no
// direct equivalent in Zig. To translate correctly, we'll have to create a C-pointer
// to the data initialized via @extern.
const name_str = try std.fmt.allocPrint(c.arena, "\"{s}\"", .{var_name});
init_node = try Tag.builtin_extern.create(c.arena, .{
.type = type_node,
.name = try Tag.string_literal.create(c.arena, name_str),
});
// Since this is really a pointer to the underlying data, we tweak a few properties.
is_extern = false;
is_const = true;
}
const linksection_string = blk: {
var str_len: usize = undefined;
if (var_decl.getSectionAttribute(&str_len)) |str_ptr| {
break :blk str_ptr[0..str_len];
}
break :blk null;
};
const node = try Tag.var_decl.create(c.arena, .{
.is_pub = is_pub,
.is_const = is_const,
.is_extern = is_extern,
.is_export = is_export,
.is_threadlocal = is_threadlocal,
.linksection_string = linksection_string,
.alignment = ClangAlignment.forVar(c, var_decl).zigAlignment(),
.name = var_name,
.type = type_node,
.init = init_node,
});
return addTopLevelDecl(c, var_name, node);
}
const builtin_typedef_map = std.StaticStringMap([]const u8).initComptime(.{
.{ "uint8_t", "u8" },
.{ "int8_t", "i8" },
.{ "uint16_t", "u16" },
.{ "int16_t", "i16" },
.{ "uint32_t", "u32" },
.{ "int32_t", "i32" },
.{ "uint64_t", "u64" },
.{ "int64_t", "i64" },
.{ "intptr_t", "isize" },
.{ "uintptr_t", "usize" },
.{ "ssize_t", "isize" },
.{ "size_t", "usize" },
});
fn transTypeDef(c: *Context, scope: *Scope, typedef_decl: *const clang.TypedefNameDecl) Error!void {
if (c.decl_table.get(@intFromPtr(typedef_decl.getCanonicalDecl()))) |_|
return; // Avoid processing this decl twice
const toplevel = scope.id == .root;
const bs: *Scope.Block = if (!toplevel) try scope.findBlockScope(c) else undefined;
var name: []const u8 = try c.str(@as(*const clang.NamedDecl, @ptrCast(typedef_decl)).getName_bytes_begin());
try c.typedefs.put(c.gpa, name, {});
if (builtin_typedef_map.get(name)) |builtin| {
return c.decl_table.putNoClobber(c.gpa, @intFromPtr(typedef_decl.getCanonicalDecl()), builtin);
}
if (!toplevel) name = try bs.makeMangledName(c, name);
try c.decl_table.putNoClobber(c.gpa, @intFromPtr(typedef_decl.getCanonicalDecl()), name);
const child_qt = typedef_decl.getUnderlyingType();
const typedef_loc = typedef_decl.getLocation();
const init_node = transQualType(c, scope, child_qt, typedef_loc) catch |err| switch (err) {
error.UnsupportedType => {
return failDecl(c, typedef_loc, name, "unable to resolve typedef child type", .{});
},
error.OutOfMemory => |e| return e,
};
const payload = try c.arena.create(ast.Payload.SimpleVarDecl);
payload.* = .{
.base = .{ .tag = ([2]Tag{ .var_simple, .pub_var_simple })[@intFromBool(toplevel)] },
.data = .{
.name = name,
.init = init_node,
},
};
const node = Node.initPayload(&payload.base);
if (toplevel) {
try addTopLevelDecl(c, name, node);
} else {
try scope.appendNode(node);
if (node.tag() != .pub_var_simple) {
try bs.discardVariable(c, name);
}
}
}
/// Build a getter function for a flexible array member at the end of a C struct
/// e.g. `T items[]` or `T items[0]`. The generated function returns a [*c] pointer
/// to the flexible array with the correct const and volatile qualifiers
fn buildFlexibleArrayFn(
c: *Context,
scope: *Scope,
layout: *const clang.ASTRecordLayout,
field_name: []const u8,
field_decl: *const clang.FieldDecl,
) TypeError!Node {
const field_qt = field_decl.getType();
const field_qt_canon = qualTypeCanon(field_qt);
const u8_type = try Tag.type.create(c.arena, "u8");
const self_param_name = "self";
const self_param = try Tag.identifier.create(c.arena, self_param_name);
const self_type = try Tag.typeof.create(c.arena, self_param);
const fn_params = try c.arena.alloc(ast.Payload.Param, 1);
fn_params[0] = .{
.name = self_param_name,
.type = Tag.@"anytype".init(),
.is_noalias = false,
};
const array_type = @as(*const clang.ArrayType, @ptrCast(field_qt_canon));
const element_qt = array_type.getElementType();
const element_type = try transQualType(c, scope, element_qt, field_decl.getLocation());
var block_scope = try Scope.Block.init(c, scope, false);
defer block_scope.deinit();
const intermediate_type_name = try block_scope.makeMangledName(c, "Intermediate");
const intermediate_type = try Tag.helpers_flexible_array_type.create(c.arena, .{ .lhs = self_type, .rhs = u8_type });
const intermediate_type_decl = try Tag.var_simple.create(c.arena, .{
.name = intermediate_type_name,
.init = intermediate_type,
});
try block_scope.statements.append(intermediate_type_decl);
const intermediate_type_ident = try Tag.identifier.create(c.arena, intermediate_type_name);
const return_type_name = try block_scope.makeMangledName(c, "ReturnType");
const return_type = try Tag.helpers_flexible_array_type.create(c.arena, .{ .lhs = self_type, .rhs = element_type });
const return_type_decl = try Tag.var_simple.create(c.arena, .{
.name = return_type_name,
.init = return_type,
});
try block_scope.statements.append(return_type_decl);
const return_type_ident = try Tag.identifier.create(c.arena, return_type_name);
const field_index = field_decl.getFieldIndex();
const bit_offset = layout.getFieldOffset(field_index); // this is a target-specific constant based on the struct layout
const byte_offset = bit_offset / 8;
const casted_self = try Tag.as.create(c.arena, .{
.lhs = intermediate_type_ident,
.rhs = try Tag.ptr_cast.create(c.arena, self_param),
});
const field_offset = try transCreateNodeNumber(c, byte_offset, .int);
const field_ptr = try Tag.add.create(c.arena, .{ .lhs = casted_self, .rhs = field_offset });
const ptr_cast = try Tag.as.create(c.arena, .{
.lhs = return_type_ident,
.rhs = try Tag.ptr_cast.create(
c.arena,
try Tag.align_cast.create(
c.arena,
field_ptr,
),
),
});
const return_stmt = try Tag.@"return".create(c.arena, ptr_cast);
try block_scope.statements.append(return_stmt);
const payload = try c.arena.create(ast.Payload.Func);
payload.* = .{
.base = .{ .tag = .func },
.data = .{
.is_pub = true,
.is_extern = false,
.is_export = false,
.is_inline = false,
.is_var_args = false,
.name = field_name,
.linksection_string = null,
.explicit_callconv = null,
.params = fn_params,
.return_type = return_type,
.body = try block_scope.complete(c),
.alignment = null,
},
};
return Node.initPayload(&payload.base);
}
/// Return true if `field_decl` is the flexible array field for its parent record
fn isFlexibleArrayFieldDecl(c: *Context, field_decl: *const clang.FieldDecl) bool {
const record_decl = field_decl.getParent() orelse return false;
const record_flexible_field = flexibleArrayField(c, record_decl) orelse return false;
return field_decl == record_flexible_field;
}
/// Find the flexible array field for a record if any. A flexible array field is an
/// incomplete or zero-length array that occurs as the last field of a record.
/// clang's RecordDecl::hasFlexibleArrayMember is not suitable for determining
/// this because it returns false for a record that ends with a zero-length
/// array, but we consider those to be flexible arrays
fn flexibleArrayField(c: *Context, record_def: *const clang.RecordDecl) ?*const clang.FieldDecl {
var it = record_def.field_begin();
const end_it = record_def.field_end();
var flexible_field: ?*const clang.FieldDecl = null;
while (it.neq(end_it)) : (it = it.next()) {
const field_decl = it.deref();
const ty = qualTypeCanon(field_decl.getType());
const incomplete_or_zero_size = ty.isIncompleteOrZeroLengthArrayType(c.clang_context);
if (incomplete_or_zero_size) {
flexible_field = field_decl;
} else {
flexible_field = null;
}
}
return flexible_field;
}
fn mangleWeakGlobalName(c: *Context, want_name: []const u8) ![]const u8 {
var cur_name = want_name;
if (!c.weak_global_names.contains(want_name)) {
// This type wasn't noticed by the name detection pass, so nothing has been treating this as
// a weak global name. We must mangle it to avoid conflicts with locals.
cur_name = try std.fmt.allocPrint(c.arena, "{s}_{d}", .{ want_name, c.getMangle() });
}
while (c.global_names.contains(cur_name)) {
cur_name = try std.fmt.allocPrint(c.arena, "{s}_{d}", .{ want_name, c.getMangle() });
}
return cur_name;
}
fn transRecordDecl(c: *Context, scope: *Scope, record_decl: *const clang.RecordDecl) Error!void {
if (c.decl_table.get(@intFromPtr(record_decl.getCanonicalDecl()))) |_|
return; // Avoid processing this decl twice
const record_loc = record_decl.getLocation();
const toplevel = scope.id == .root;
const bs: *Scope.Block = if (!toplevel) try scope.findBlockScope(c) else undefined;
var is_union = false;
var container_kind_name: []const u8 = undefined;
var bare_name: []const u8 = try c.str(@as(*const clang.NamedDecl, @ptrCast(record_decl)).getName_bytes_begin());
if (record_decl.isUnion()) {
container_kind_name = "union";
is_union = true;
} else if (record_decl.isStruct()) {
container_kind_name = "struct";
} else {
try c.decl_table.putNoClobber(c.gpa, @intFromPtr(record_decl.getCanonicalDecl()), bare_name);
return failDecl(c, record_loc, bare_name, "record {s} is not a struct or union", .{bare_name});
}
var is_unnamed = false;
var name = bare_name;
if (c.unnamed_typedefs.get(@intFromPtr(record_decl.getCanonicalDecl()))) |typedef_name| {
bare_name = typedef_name;
name = typedef_name;
} else {
// Record declarations such as `struct {...} x` have no name but they're not
// anonymous hence here isAnonymousStructOrUnion is not needed
if (bare_name.len == 0) {
bare_name = try std.fmt.allocPrint(c.arena, "unnamed_{d}", .{c.getMangle()});
is_unnamed = true;
}
name = try std.fmt.allocPrint(c.arena, "{s}_{s}", .{ container_kind_name, bare_name });
if (toplevel and !is_unnamed) {
name = try mangleWeakGlobalName(c, name);
}
}
if (!toplevel) name = try bs.makeMangledName(c, name);
try c.decl_table.putNoClobber(c.gpa, @intFromPtr(record_decl.getCanonicalDecl()), name);
const is_pub = toplevel and !is_unnamed;
const init_node = blk: {
const record_def = record_decl.getDefinition() orelse {
try c.opaque_demotes.put(c.gpa, @intFromPtr(record_decl.getCanonicalDecl()), {});
break :blk Tag.opaque_literal.init();
};
var fields = std.array_list.Managed(ast.Payload.Record.Field).init(c.gpa);
defer fields.deinit();
var functions = std.array_list.Managed(Node).init(c.gpa);
defer functions.deinit();
const flexible_field = flexibleArrayField(c, record_def);
var unnamed_field_count: u32 = 0;
var it = record_def.field_begin();
const end_it = record_def.field_end();
const layout = record_def.getASTRecordLayout(c.clang_context);
const record_alignment = layout.getAlignment();
while (it.neq(end_it)) : (it = it.next()) {
const field_decl = it.deref();
const field_loc = field_decl.getLocation();
const field_qt = field_decl.getType();
if (field_decl.isBitField()) {
try c.opaque_demotes.put(c.gpa, @intFromPtr(record_decl.getCanonicalDecl()), {});
try warn(c, scope, field_loc, "{s} demoted to opaque type - has bitfield", .{container_kind_name});
break :blk Tag.opaque_literal.init();
}
var is_anon = false;
var field_name = try c.str(@as(*const clang.NamedDecl, @ptrCast(field_decl)).getName_bytes_begin());
if (field_decl.isAnonymousStructOrUnion() or field_name.len == 0) {
// Context.getMangle() is not used here because doing so causes unpredictable field names for anonymous fields.
field_name = try std.fmt.allocPrint(c.arena, "unnamed_{d}", .{unnamed_field_count});
unnamed_field_count += 1;
is_anon = true;
}
if (flexible_field == field_decl) {
const flexible_array_fn = buildFlexibleArrayFn(c, scope, layout, field_name, field_decl) catch |err| switch (err) {
error.UnsupportedType => {
try c.opaque_demotes.put(c.gpa, @intFromPtr(record_decl.getCanonicalDecl()), {});
try warn(c, scope, record_loc, "{s} demoted to opaque type - unable to translate type of flexible array field {s}", .{ container_kind_name, field_name });
break :blk Tag.opaque_literal.init();
},
else => |e| return e,
};
try functions.append(flexible_array_fn);
continue;
}
const field_type = transQualType(c, scope, field_qt, field_loc) catch |err| switch (err) {
error.UnsupportedType => {
try c.opaque_demotes.put(c.gpa, @intFromPtr(record_decl.getCanonicalDecl()), {});
try warn(c, scope, record_loc, "{s} demoted to opaque type - unable to translate type of field {s}", .{ container_kind_name, field_name });
break :blk Tag.opaque_literal.init();
},
else => |e| return e,
};
const alignment = if (flexible_field != null and field_decl.getFieldIndex() == 0)
@as(c_uint, @intCast(record_alignment))
else
ClangAlignment.forField(c, field_decl, record_def).zigAlignment();
// C99 introduced designated initializers for structs. Omitted fields are implicitly
// initialized to zero. Some C APIs are designed with this in mind. Defaulting to zero
// values for translated struct fields permits Zig code to comfortably use such an API.
const default_value = if (record_decl.isStruct())
try Tag.std_mem_zeroes.create(c.arena, field_type)
else
null;
if (is_anon) {
try c.decl_table.putNoClobber(c.gpa, @intFromPtr(field_decl.getCanonicalDecl()), field_name);
}
try fields.append(.{
.name = field_name,
.type = field_type,
.alignment = alignment,
.default_value = default_value,
});
}
const record_payload = try c.arena.create(ast.Payload.Record);
record_payload.* = .{
.base = .{ .tag = ([2]Tag{ .@"struct", .@"union" })[@intFromBool(is_union)] },
.data = .{
.layout = .@"extern",
.fields = try c.arena.dupe(ast.Payload.Record.Field, fields.items),
.functions = try c.arena.dupe(Node, functions.items),
.variables = &.{},
},
};
break :blk Node.initPayload(&record_payload.base);
};
const payload = try c.arena.create(ast.Payload.SimpleVarDecl);
payload.* = .{
.base = .{ .tag = ([2]Tag{ .var_simple, .pub_var_simple })[@intFromBool(is_pub)] },
.data = .{
.name = name,
.init = init_node,
},
};
const node = Node.initPayload(&payload.base);
if (toplevel) {
try addTopLevelDecl(c, name, node);
// Only add the alias if the name is available *and* it was caught by
// name detection. Don't bother performing a weak mangle, since a
// mangled name is of no real use here.
if (!is_unnamed and !c.global_names.contains(bare_name) and c.weak_global_names.contains(bare_name))
try c.alias_list.append(.{ .alias = bare_name, .name = name });
} else {
try scope.appendNode(node);
if (node.tag() != .pub_var_simple) {
try bs.discardVariable(c, name);
}
}
}
fn transEnumDecl(c: *Context, scope: *Scope, enum_decl: *const clang.EnumDecl) Error!void {
if (c.decl_table.get(@intFromPtr(enum_decl.getCanonicalDecl()))) |_|
return; // Avoid processing this decl twice
const enum_loc = enum_decl.getLocation();
const toplevel = scope.id == .root;
const bs: *Scope.Block = if (!toplevel) try scope.findBlockScope(c) else undefined;
var is_unnamed = false;
var bare_name: []const u8 = try c.str(@as(*const clang.NamedDecl, @ptrCast(enum_decl)).getName_bytes_begin());
var name = bare_name;
if (c.unnamed_typedefs.get(@intFromPtr(enum_decl.getCanonicalDecl()))) |typedef_name| {
bare_name = typedef_name;
name = typedef_name;
} else {
if (bare_name.len == 0) {
bare_name = try std.fmt.allocPrint(c.arena, "unnamed_{d}", .{c.getMangle()});
is_unnamed = true;
}
name = try std.fmt.allocPrint(c.arena, "enum_{s}", .{bare_name});
if (toplevel and !is_unnamed) {
name = try mangleWeakGlobalName(c, name);
}
}
if (!toplevel) name = try bs.makeMangledName(c, name);
try c.decl_table.putNoClobber(c.gpa, @intFromPtr(enum_decl.getCanonicalDecl()), name);
const enum_type_node = if (enum_decl.getDefinition()) |enum_def| blk: {
var it = enum_def.enumerator_begin();
const end_it = enum_def.enumerator_end();
while (it.neq(end_it)) : (it = it.next()) {
const enum_const = it.deref();
var enum_val_name: []const u8 = try c.str(@as(*const clang.NamedDecl, @ptrCast(enum_const)).getName_bytes_begin());
if (!toplevel) {
enum_val_name = try bs.makeMangledName(c, enum_val_name);
}
const enum_const_qt = @as(*const clang.ValueDecl, @ptrCast(enum_const)).getType();
const enum_const_loc = @as(*const clang.Decl, @ptrCast(enum_const)).getLocation();
const enum_const_type_node: ?Node = transQualType(c, scope, enum_const_qt, enum_const_loc) catch |err| switch (err) {
error.UnsupportedType => null,
else => |e| return e,
};
const enum_const_def = try Tag.enum_constant.create(c.arena, .{
.name = enum_val_name,
.is_public = toplevel,
.type = enum_const_type_node,
// TODO: as of LLVM 18, the return value from `enum_const.getInitVal` here needs
// to be freed with a call to its free() method.
.value = try transCreateNodeAPInt(c, enum_const.getInitVal()),
});
if (toplevel)
try addTopLevelDecl(c, enum_val_name, enum_const_def)
else {
try scope.appendNode(enum_const_def);
try bs.discardVariable(c, enum_val_name);
}
}
const int_type = enum_decl.getIntegerType();
// The underlying type may be null in case of forward-declared enum
// types, while that's not ISO-C compliant many compilers allow this and
// default to the usual integer type used for all the enums.
// default to c_int since msvc and gcc default to different types
break :blk if (int_type.ptr != null)
transQualType(c, scope, int_type, enum_loc) catch |err| switch (err) {
error.UnsupportedType => {
return failDecl(c, enum_loc, name, "unable to translate enum integer type", .{});
},
else => |e| return e,
}
else
try Tag.type.create(c.arena, "c_int");
} else blk: {
try c.opaque_demotes.put(c.gpa, @intFromPtr(enum_decl.getCanonicalDecl()), {});
break :blk Tag.opaque_literal.init();
};
const is_pub = toplevel and !is_unnamed;
const payload = try c.arena.create(ast.Payload.SimpleVarDecl);
payload.* = .{
.base = .{ .tag = ([2]Tag{ .var_simple, .pub_var_simple })[@intFromBool(is_pub)] },
.data = .{
.init = enum_type_node,
.name = name,
},
};
const node = Node.initPayload(&payload.base);
if (toplevel) {
try addTopLevelDecl(c, name, node);
// Only add the alias if the name is available *and* it was caught by
// name detection. Don't bother performing a weak mangle, since a
// mangled name is of no real use here.
if (!is_unnamed and !c.global_names.contains(bare_name) and c.weak_global_names.contains(bare_name))
try c.alias_list.append(.{ .alias = bare_name, .name = name });
} else {
try scope.appendNode(node);
if (node.tag() != .pub_var_simple) {
try bs.discardVariable(c, name);
}
}
}
fn transStmt(
c: *Context,
scope: *Scope,
stmt: *const clang.Stmt,
result_used: ResultUsed,
) TransError!Node {
const sc = stmt.getStmtClass();
switch (sc) {
.BinaryOperatorClass => return transBinaryOperator(c, scope, @as(*const clang.BinaryOperator, @ptrCast(stmt)), result_used),
.CompoundStmtClass => return transCompoundStmt(c, scope, @as(*const clang.CompoundStmt, @ptrCast(stmt))),
.CStyleCastExprClass => return transCStyleCastExprClass(c, scope, @as(*const clang.CStyleCastExpr, @ptrCast(stmt)), result_used),
.DeclStmtClass => return transDeclStmt(c, scope, @as(*const clang.DeclStmt, @ptrCast(stmt))),
.DeclRefExprClass => return transDeclRefExpr(c, scope, @as(*const clang.DeclRefExpr, @ptrCast(stmt))),
.ImplicitCastExprClass => return transImplicitCastExpr(c, scope, @as(*const clang.ImplicitCastExpr, @ptrCast(stmt)), result_used),
.IntegerLiteralClass => return transIntegerLiteral(c, scope, @as(*const clang.IntegerLiteral, @ptrCast(stmt)), result_used, .with_as),
.ReturnStmtClass => return transReturnStmt(c, scope, @as(*const clang.ReturnStmt, @ptrCast(stmt))),
.StringLiteralClass => return transStringLiteral(c, scope, @as(*const clang.StringLiteral, @ptrCast(stmt)), result_used),
.ParenExprClass => {
const expr = try transExpr(c, scope, @as(*const clang.ParenExpr, @ptrCast(stmt)).getSubExpr(), .used);
return maybeSuppressResult(c, result_used, expr);
},
.InitListExprClass => return transInitListExpr(c, scope, @as(*const clang.InitListExpr, @ptrCast(stmt)), result_used),
.ImplicitValueInitExprClass => return transImplicitValueInitExpr(c, scope, @as(*const clang.Expr, @ptrCast(stmt))),
.IfStmtClass => return transIfStmt(c, scope, @as(*const clang.IfStmt, @ptrCast(stmt))),
.WhileStmtClass => return transWhileLoop(c, scope, @as(*const clang.WhileStmt, @ptrCast(stmt))),
.DoStmtClass => return transDoWhileLoop(c, scope, @as(*const clang.DoStmt, @ptrCast(stmt))),
.NullStmtClass => {
return Tag.empty_block.init();
},
.ContinueStmtClass => return Tag.@"continue".init(),
.BreakStmtClass => return Tag.@"break".init(),
.ForStmtClass => return transForLoop(c, scope, @as(*const clang.ForStmt, @ptrCast(stmt))),
.FloatingLiteralClass => return transFloatingLiteral(c, @as(*const clang.FloatingLiteral, @ptrCast(stmt)), result_used),
.ConditionalOperatorClass => {
return transConditionalOperator(c, scope, @as(*const clang.ConditionalOperator, @ptrCast(stmt)), result_used);
},
.BinaryConditionalOperatorClass => {
return transBinaryConditionalOperator(c, scope, @as(*const clang.BinaryConditionalOperator, @ptrCast(stmt)), result_used);
},
.SwitchStmtClass => return transSwitch(c, scope, @as(*const clang.SwitchStmt, @ptrCast(stmt))),
.CaseStmtClass, .DefaultStmtClass => {
return fail(c, error.UnsupportedTranslation, stmt.getBeginLoc(), "TODO complex switch", .{});
},
.ConstantExprClass => return transConstantExpr(c, scope, @as(*const clang.Expr, @ptrCast(stmt)), result_used),
.PredefinedExprClass => return transPredefinedExpr(c, scope, @as(*const clang.PredefinedExpr, @ptrCast(stmt)), result_used),
.CharacterLiteralClass => return transCharLiteral(c, scope, @as(*const clang.CharacterLiteral, @ptrCast(stmt)), result_used, .with_as),
.StmtExprClass => return transStmtExpr(c, scope, @as(*const clang.StmtExpr, @ptrCast(stmt)), result_used),
.MemberExprClass => return transMemberExpr(c, scope, @as(*const clang.MemberExpr, @ptrCast(stmt)), result_used),
.ArraySubscriptExprClass => return transArrayAccess(c, scope, @as(*const clang.ArraySubscriptExpr, @ptrCast(stmt)), result_used),
.CallExprClass => return transCallExpr(c, scope, @as(*const clang.CallExpr, @ptrCast(stmt)), result_used),
.UnaryExprOrTypeTraitExprClass => return transUnaryExprOrTypeTraitExpr(c, scope, @as(*const clang.UnaryExprOrTypeTraitExpr, @ptrCast(stmt)), result_used),
.UnaryOperatorClass => return transUnaryOperator(c, scope, @as(*const clang.UnaryOperator, @ptrCast(stmt)), result_used),
.CompoundAssignOperatorClass => return transCompoundAssignOperator(c, scope, @as(*const clang.CompoundAssignOperator, @ptrCast(stmt)), result_used),
.OpaqueValueExprClass => {
const source_expr = @as(*const clang.OpaqueValueExpr, @ptrCast(stmt)).getSourceExpr().?;
const expr = try transExpr(c, scope, source_expr, .used);
return maybeSuppressResult(c, result_used, expr);
},
.OffsetOfExprClass => return transOffsetOfExpr(c, @as(*const clang.OffsetOfExpr, @ptrCast(stmt)), result_used),
.CompoundLiteralExprClass => {
const compound_literal = @as(*const clang.CompoundLiteralExpr, @ptrCast(stmt));
return transExpr(c, scope, compound_literal.getInitializer(), result_used);
},
.GenericSelectionExprClass => {
const gen_sel = @as(*const clang.GenericSelectionExpr, @ptrCast(stmt));
return transExpr(c, scope, gen_sel.getResultExpr(), result_used);
},
.ConvertVectorExprClass => {
const conv_vec = @as(*const clang.ConvertVectorExpr, @ptrCast(stmt));
const conv_vec_node = try transConvertVectorExpr(c, scope, conv_vec);
return maybeSuppressResult(c, result_used, conv_vec_node);
},
.ShuffleVectorExprClass => {
const shuffle_vec_expr = @as(*const clang.ShuffleVectorExpr, @ptrCast(stmt));
const shuffle_vec_node = try transShuffleVectorExpr(c, scope, shuffle_vec_expr);
return maybeSuppressResult(c, result_used, shuffle_vec_node);
},
.ChooseExprClass => {
const choose_expr = @as(*const clang.ChooseExpr, @ptrCast(stmt));
return transExpr(c, scope, choose_expr.getChosenSubExpr(), result_used);
},
// When adding new cases here, see comment for maybeBlockify()
.GCCAsmStmtClass,
.GotoStmtClass,
.IndirectGotoStmtClass,
.AttributedStmtClass,
.AddrLabelExprClass,
.AtomicExprClass,
.BlockExprClass,
.UserDefinedLiteralClass,
.BuiltinBitCastExprClass,
.DesignatedInitExprClass,
.LabelStmtClass,
=> return fail(c, error.UnsupportedTranslation, stmt.getBeginLoc(), "TODO implement translation of stmt class {s}", .{@tagName(sc)}),
else => return fail(c, error.UnsupportedTranslation, stmt.getBeginLoc(), "unsupported stmt class {s}", .{@tagName(sc)}),
}
}
/// See https://clang.llvm.org/docs/LanguageExtensions.html#langext-builtin-convertvector
fn transConvertVectorExpr(
c: *Context,
scope: *Scope,
expr: *const clang.ConvertVectorExpr,
) TransError!Node {
const base_stmt = @as(*const clang.Stmt, @ptrCast(expr));
var block_scope = try Scope.Block.init(c, scope, true);
defer block_scope.deinit();
const src_expr = expr.getSrcExpr();
const src_type = qualTypeCanon(src_expr.getType());
const src_vector_ty = @as(*const clang.VectorType, @ptrCast(src_type));
const src_element_qt = src_vector_ty.getElementType();
const src_expr_node = try transExpr(c, &block_scope.base, src_expr, .used);
const dst_qt = expr.getTypeSourceInfo_getType();
const dst_type_node = try transQualType(c, &block_scope.base, dst_qt, base_stmt.getBeginLoc());
const dst_vector_ty = @as(*const clang.VectorType, @ptrCast(qualTypeCanon(dst_qt)));
const num_elements = dst_vector_ty.getNumElements();
const dst_element_qt = dst_vector_ty.getElementType();
// workaround for https://github.com/ziglang/zig/issues/8322
// we store the casted results into temp variables and use those
// to initialize the vector. Eventually we can just directly
// construct the init_list from casted source members
var i: usize = 0;
while (i < num_elements) : (i += 1) {
const mangled_name = try block_scope.makeMangledName(c, "tmp");
const value = try Tag.array_access.create(c.arena, .{
.lhs = src_expr_node,
.rhs = try transCreateNodeNumber(c, i, .int),
});
const tmp_decl_node = try Tag.var_simple.create(c.arena, .{
.name = mangled_name,
.init = try transCCast(c, &block_scope.base, base_stmt.getBeginLoc(), dst_element_qt, src_element_qt, value),
});
try block_scope.statements.append(tmp_decl_node);
}
const init_list = try c.arena.alloc(Node, num_elements);
for (init_list, 0..) |*init, init_index| {
const tmp_decl = block_scope.statements.items[init_index];
const name = tmp_decl.castTag(.var_simple).?.data.name;
init.* = try Tag.identifier.create(c.arena, name);
}
const vec_init = try Tag.array_init.create(c.arena, .{
.cond = dst_type_node,
.cases = init_list,
});
const break_node = try Tag.break_val.create(c.arena, .{
.label = block_scope.label,
.val = vec_init,
});
try block_scope.statements.append(break_node);
return block_scope.complete(c);
}
fn makeShuffleMask(c: *Context, scope: *Scope, expr: *const clang.ShuffleVectorExpr, vector_len: Node) TransError!Node {
const num_subexprs = expr.getNumSubExprs();
assert(num_subexprs >= 3); // two source vectors + at least 1 index expression
const mask_len = num_subexprs - 2;
const mask_type = try Tag.vector.create(c.arena, .{
.lhs = try transCreateNodeNumber(c, mask_len, .int),
.rhs = try Tag.type.create(c.arena, "i32"),
});
const init_list = try c.arena.alloc(Node, mask_len);
for (init_list, 0..) |*init, i| {
const index_expr = try transExprCoercing(c, scope, expr.getExpr(@as(c_uint, @intCast(i + 2))), .used);
const converted_index = try Tag.helpers_shuffle_vector_index.create(c.arena, .{ .lhs = index_expr, .rhs = vector_len });
init.* = converted_index;
}
return Tag.array_init.create(c.arena, .{
.cond = mask_type,
.cases = init_list,
});
}
/// @typeInfo(@TypeOf(vec_node)).Vector.<field>
fn vectorTypeInfo(arena: mem.Allocator, vec_node: Node, field: []const u8) TransError!Node {
const typeof_call = try Tag.typeof.create(arena, vec_node);
const typeinfo_call = try Tag.typeinfo.create(arena, typeof_call);
const vector_type_info = try Tag.field_access.create(arena, .{ .lhs = typeinfo_call, .field_name = "vector" });
return Tag.field_access.create(arena, .{ .lhs = vector_type_info, .field_name = field });
}
fn transShuffleVectorExpr(
c: *Context,
scope: *Scope,
expr: *const clang.ShuffleVectorExpr,
) TransError!Node {
const base_expr = @as(*const clang.Expr, @ptrCast(expr));
const num_subexprs = expr.getNumSubExprs();
if (num_subexprs < 3) return fail(c, error.UnsupportedTranslation, base_expr.getBeginLoc(), "ShuffleVector needs at least 1 index", .{});
const a = try transExpr(c, scope, expr.getExpr(0), .used);
const b = try transExpr(c, scope, expr.getExpr(1), .used);
// clang requires first two arguments to __builtin_shufflevector to be same type
const vector_child_type = try vectorTypeInfo(c.arena, a, "child");
const vector_len = try vectorTypeInfo(c.arena, a, "len");
const shuffle_mask = try makeShuffleMask(c, scope, expr, vector_len);
return Tag.shuffle.create(c.arena, .{
.element_type = vector_child_type,
.a = a,
.b = b,
.mask_vector = shuffle_mask,
});
}
/// Translate a "simple" offsetof expression containing exactly one component,
/// when that component is of kind .Field - e.g. offsetof(mytype, myfield)
fn transSimpleOffsetOfExpr(c: *Context, expr: *const clang.OffsetOfExpr) TransError!Node {
assert(expr.getNumComponents() == 1);
const component = expr.getComponent(0);
if (component.getKind() == .Field) {
const field_decl = component.getField();
if (field_decl.getParent()) |record_decl| {
if (c.decl_table.get(@intFromPtr(record_decl.getCanonicalDecl()))) |type_name| {
const type_node = try Tag.type.create(c.arena, type_name);
const raw_field_name = try c.str(@as(*const clang.NamedDecl, @ptrCast(field_decl)).getName_bytes_begin());
const quoted_field_name = try std.fmt.allocPrint(c.arena, "\"{s}\"", .{raw_field_name});
const field_name_node = try Tag.string_literal.create(c.arena, quoted_field_name);
return Tag.offset_of.create(c.arena, .{
.lhs = type_node,
.rhs = field_name_node,
});
}
}
}
return fail(c, error.UnsupportedTranslation, expr.getBeginLoc(), "failed to translate simple OffsetOfExpr", .{});
}
fn transOffsetOfExpr(
c: *Context,
expr: *const clang.OffsetOfExpr,
result_used: ResultUsed,
) TransError!Node {
if (expr.getNumComponents() == 1) {
const offsetof_expr = try transSimpleOffsetOfExpr(c, expr);
return maybeSuppressResult(c, result_used, offsetof_expr);
}
// TODO implement OffsetOfExpr with more than 1 component
// OffsetOfExpr API:
// call expr.getComponent(idx) while idx < expr.getNumComponents()
// component.getKind() will be either .Array or .Field (other kinds are C++-only)
// if .Field, use component.getField() to retrieve *clang.FieldDecl
// if .Array, use component.getArrayExprIndex() to get a c_uint which
// can be passed to expr.getIndexExpr(expr_index) to get the *clang.Expr for the array index
return fail(c, error.UnsupportedTranslation, expr.getBeginLoc(), "TODO: implement complex OffsetOfExpr translation", .{});
}
/// Cast a signed integer node to a usize, for use in pointer arithmetic. Negative numbers
/// will become very large positive numbers but that is ok since we only use this in
/// pointer arithmetic expressions, where wraparound will ensure we get the correct value.
/// node -> @bitCast(usize, @intCast(isize, node))
fn usizeCastForWrappingPtrArithmetic(gpa: mem.Allocator, node: Node) TransError!Node {
const intcast_node = try Tag.as.create(gpa, .{
.lhs = try Tag.type.create(gpa, "isize"),
.rhs = try Tag.int_cast.create(gpa, node),
});
return Tag.as.create(gpa, .{
.lhs = try Tag.type.create(gpa, "usize"),
.rhs = try Tag.bit_cast.create(gpa, intcast_node),
});
}
/// Translate an arithmetic expression with a pointer operand and a signed-integer operand.
/// Zig requires a usize argument for pointer arithmetic, so we intCast to isize and then
/// bitcast to usize; pointer wraparound make the math work.
/// Zig pointer addition is not commutative (unlike C); the pointer operand needs to be on the left.
/// The + operator in C is not a sequence point so it should be safe to switch the order if necessary.
fn transCreatePointerArithmeticSignedOp(
c: *Context,
scope: *Scope,
stmt: *const clang.BinaryOperator,
result_used: ResultUsed,
) TransError!Node {
const is_add = stmt.getOpcode() == .Add;
const lhs = stmt.getLHS();
const rhs = stmt.getRHS();
const swap_operands = is_add and cIsSignedInteger(getExprQualType(c, lhs));
const swizzled_lhs = if (swap_operands) rhs else lhs;
const swizzled_rhs = if (swap_operands) lhs else rhs;
const lhs_node = try transExpr(c, scope, swizzled_lhs, .used);
const rhs_node = try transExpr(c, scope, swizzled_rhs, .used);
const bitcast_node = try usizeCastForWrappingPtrArithmetic(c.arena, rhs_node);
return transCreateNodeInfixOp(
c,
if (is_add) .add else .sub,
lhs_node,
bitcast_node,
result_used,
);
}
fn transBinaryOperator(
c: *Context,
scope: *Scope,
stmt: *const clang.BinaryOperator,
result_used: ResultUsed,
) TransError!Node {
const op = stmt.getOpcode();
const qt = stmt.getType();
const isPointerDiffExpr = cIsPointerDiffExpr(stmt);
switch (op) {
.Assign => return try transCreateNodeAssign(c, scope, result_used, stmt.getLHS(), stmt.getRHS()),
.Comma => {
var block_scope = try Scope.Block.init(c, scope, true);
defer block_scope.deinit();
const lhs = try transExpr(c, &block_scope.base, stmt.getLHS(), .unused);
try block_scope.statements.append(lhs);
const rhs = try transExpr(c, &block_scope.base, stmt.getRHS(), .used);
const break_node = try Tag.break_val.create(c.arena, .{
.label = block_scope.label,
.val = rhs,
});
try block_scope.statements.append(break_node);
const block_node = try block_scope.complete(c);
return maybeSuppressResult(c, result_used, block_node);
},
.Div => {
if (cIsSignedInteger(qt)) {
// signed integer division uses @divTrunc
const lhs = try transExpr(c, scope, stmt.getLHS(), .used);
const rhs = try transExpr(c, scope, stmt.getRHS(), .used);
const div_trunc = try Tag.div_trunc.create(c.arena, .{ .lhs = lhs, .rhs = rhs });
return maybeSuppressResult(c, result_used, div_trunc);
}
},
.Rem => {
if (cIsSignedInteger(qt)) {
// signed integer remainder uses std.zig.c_translation.signedRemainder
const lhs = try transExpr(c, scope, stmt.getLHS(), .used);
const rhs = try transExpr(c, scope, stmt.getRHS(), .used);
const rem = try Tag.signed_remainder.create(c.arena, .{ .lhs = lhs, .rhs = rhs });
return maybeSuppressResult(c, result_used, rem);
}
},
.Shl => {
return transCreateNodeShiftOp(c, scope, stmt, .shl, result_used);
},
.Shr => {
return transCreateNodeShiftOp(c, scope, stmt, .shr, result_used);
},
.LAnd => {
return transCreateNodeBoolInfixOp(c, scope, stmt, .@"and", result_used);
},
.LOr => {
return transCreateNodeBoolInfixOp(c, scope, stmt, .@"or", result_used);
},
.Add, .Sub => {
// `ptr + idx` and `idx + ptr` -> ptr + @bitCast(usize, @intCast(isize, idx))
// `ptr - idx` -> ptr - @bitCast(usize, @intCast(isize, idx))
if (qualTypeIsPtr(qt) and (cIsSignedInteger(getExprQualType(c, stmt.getLHS())) or
cIsSignedInteger(getExprQualType(c, stmt.getRHS())))) return transCreatePointerArithmeticSignedOp(c, scope, stmt, result_used);
},
else => {},
}
var op_id: Tag = undefined;
switch (op) {
.Add => {
if (cIsUnsignedInteger(qt)) {
op_id = .add_wrap;
} else {
op_id = .add;
}
},
.Sub => {
if (cIsUnsignedInteger(qt) or isPointerDiffExpr) {
op_id = .sub_wrap;
} else {
op_id = .sub;
}
},
.Mul => {
if (cIsUnsignedInteger(qt)) {
op_id = .mul_wrap;
} else {
op_id = .mul;
}
},
.Div => {
// unsigned/float division uses the operator
op_id = .div;
},
.Rem => {
// unsigned/float division uses the operator
op_id = .mod;
},
.LT => {
op_id = .less_than;
},
.GT => {
op_id = .greater_than;
},
.LE => {
op_id = .less_than_equal;
},
.GE => {
op_id = .greater_than_equal;
},
.EQ => {
op_id = .equal;
},
.NE => {
op_id = .not_equal;
},
.And => {
op_id = .bit_and;
},
.Xor => {
op_id = .bit_xor;
},
.Or => {
op_id = .bit_or;
},
else => unreachable,
}
const lhs_uncasted = try transExpr(c, scope, stmt.getLHS(), .used);
const rhs_uncasted = try transExpr(c, scope, stmt.getRHS(), .used);
const lhs = if (isBoolRes(lhs_uncasted))
try Tag.int_from_bool.create(c.arena, lhs_uncasted)
else if (isPointerDiffExpr)
try Tag.int_from_ptr.create(c.arena, lhs_uncasted)
else
lhs_uncasted;
const rhs = if (isBoolRes(rhs_uncasted))
try Tag.int_from_bool.create(c.arena, rhs_uncasted)
else if (isPointerDiffExpr)
try Tag.int_from_ptr.create(c.arena, rhs_uncasted)
else
rhs_uncasted;
const infixOpNode = try transCreateNodeInfixOp(c, op_id, lhs, rhs, result_used);
if (isPointerDiffExpr) {
// @divExact(@bitCast(<platform-ptrdiff_t>, @intFromPtr(lhs) -% @intFromPtr(rhs)), @sizeOf(<lhs target type>))
const ptrdiff_type = try transQualTypeIntWidthOf(c, qt, true);
const bitcast = try Tag.as.create(c.arena, .{
.lhs = ptrdiff_type,
.rhs = try Tag.bit_cast.create(c.arena, infixOpNode),
});
// C standard requires that pointer subtraction operands are of the same type,
// otherwise it is undefined behavior. So we can assume the left and right
// sides are the same QualType and arbitrarily choose left.
const lhs_expr = stmt.getLHS();
const lhs_qt = getExprQualType(c, lhs_expr);
const lhs_qt_translated = try transQualType(c, scope, lhs_qt, lhs_expr.getBeginLoc());
const c_pointer = getContainer(c, lhs_qt_translated).?;
if (c_pointer.castTag(.c_pointer)) |c_pointer_payload| {
const sizeof = try Tag.sizeof.create(c.arena, c_pointer_payload.data.elem_type);
return Tag.div_exact.create(c.arena, .{
.lhs = bitcast,
.rhs = sizeof,
});
} else {
// This is an opaque/incomplete type. This subtraction exhibits Undefined Behavior by the C99 spec.
// However, allowing subtraction on `void *` and function pointers is a commonly used extension.
// So, just return the value in byte units, mirroring the behavior of this language extension as implemented by GCC and Clang.
return bitcast;
}
}
return infixOpNode;
}
fn transCompoundStmtInline(
c: *Context,
stmt: *const clang.CompoundStmt,
block: *Scope.Block,
) TransError!void {
var it = stmt.body_begin();
const end_it = stmt.body_end();
while (it != end_it) : (it += 1) {
const result = try transStmt(c, &block.base, it[0], .unused);
switch (result.tag()) {
.declaration, .empty_block => {},
else => try block.statements.append(result),
}
}
}
fn transCompoundStmt(c: *Context, scope: *Scope, stmt: *const clang.CompoundStmt) TransError!Node {
var block_scope = try Scope.Block.init(c, scope, false);
defer block_scope.deinit();
try transCompoundStmtInline(c, stmt, &block_scope);
return try block_scope.complete(c);
}
fn transCStyleCastExprClass(
c: *Context,
scope: *Scope,
stmt: *const clang.CStyleCastExpr,
result_used: ResultUsed,
) TransError!Node {
const cast_expr = @as(*const clang.CastExpr, @ptrCast(stmt));
const sub_expr = stmt.getSubExpr();
const dst_type = stmt.getType();
const src_type = sub_expr.getType();
const sub_expr_node = try transExpr(c, scope, sub_expr, .used);
const loc = stmt.getBeginLoc();
const cast_node = if (cast_expr.getCastKind() == .ToUnion) blk: {
const field_decl = cast_expr.getTargetFieldForToUnionCast(dst_type, src_type).?; // C syntax error if target field is null
const field_name = try c.str(@as(*const clang.NamedDecl, @ptrCast(field_decl)).getName_bytes_begin());
const union_ty = try transQualType(c, scope, dst_type, loc);
const inits = [1]ast.Payload.ContainerInit.Initializer{.{ .name = field_name, .value = sub_expr_node }};
break :blk try Tag.container_init.create(c.arena, .{
.lhs = union_ty,
.inits = try c.arena.dupe(ast.Payload.ContainerInit.Initializer, &inits),
});
} else (try transCCast(
c,
scope,
loc,
dst_type,
src_type,
sub_expr_node,
));
return maybeSuppressResult(c, result_used, cast_node);
}
/// The alignment of a variable or field
const ClangAlignment = struct {
/// Clang reports the alignment in bits, we use bytes
/// Clang uses 0 for "no alignment specified", we use null
bit_alignment: c_uint,
/// If the field or variable is marked as 'packed'
///
/// According to the GCC variable attribute docs, this impacts alignment
/// https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html
///
/// > The packed attribute specifies that a structure member
/// > should have the smallest possible alignment
///
/// Note also that specifying the 'packed' attribute on a structure
/// implicitly packs all its fields (making their alignment 1).
///
/// This will be null if the AST node doesn't support packing (functions)
is_packed: ?bool,
/// Get the alignment for a field, optionally taking into account the parent record
pub fn forField(c: *const Context, field: *const clang.FieldDecl, parent: ?*const clang.RecordDecl) ClangAlignment {
const parent_packed = if (parent) |record| record.getPackedAttribute() else false;
// NOTE: According to GCC docs, parent attribute packed implies child attribute packed
return ClangAlignment{
.bit_alignment = field.getAlignedAttribute(c.clang_context),
.is_packed = field.getPackedAttribute() or parent_packed,
};
}
pub fn forVar(c: *const Context, var_decl: *const clang.VarDecl) ClangAlignment {
return ClangAlignment{
.bit_alignment = var_decl.getAlignedAttribute(c.clang_context),
.is_packed = var_decl.getPackedAttribute(),
};
}
pub fn forFunc(c: *const Context, fun: *const clang.FunctionDecl) ClangAlignment {
return ClangAlignment{
.bit_alignment = fun.getAlignedAttribute(c.clang_context),
.is_packed = null, // not supported by GCC/clang (or meaningful),
};
}
/// Translate the clang alignment info into a zig alignment
///
/// Returns null if there is no special alignment info
pub fn zigAlignment(self: ClangAlignment) ?c_uint {
if (self.bit_alignment != 0) {
return self.bit_alignment / 8;
} else if (self.is_packed orelse false) {
return 1;
} else {
return null;
}
}
};
/// Translate an "extern" variable that's been declared within a scoped block.
/// Similar to static local variables, this will be wrapped in a struct to work with Zig's syntax requirements.
///
/// Assumptions made:
/// - No need to mangle the actual NamedDecl, as by definition this MUST be the same name as the external symbol it's referencing
/// - It's not valid C to have an initializer with this type of declaration, so we can safely operate assuming no initializer
/// - No need to look for any cleanup attributes with getCleanupAttribute(), not relevant for this type of decl
fn transLocalExternStmt(c: *Context, scope: *Scope, var_decl: *const clang.VarDecl, block_scope: *Scope.Block) TransError!void {
const extern_var_name = try c.str(@as(*const clang.NamedDecl, @ptrCast(var_decl)).getName_bytes_begin());
// Special naming convention for local extern variable wrapper struct
const name = try std.fmt.allocPrint(c.arena, "{s}_{s}", .{ Scope.Block.extern_inner_prepend, extern_var_name });
// On the off chance there's already a variable in scope named "ExternLocal_[extern_var_name]"
const mangled_name = try block_scope.makeMangledName(c, name);
const qual_type = var_decl.getTypeSourceInfo_getType();
const is_const = qual_type.isConstQualified();
const loc = var_decl.getLocation();
const type_node = try transQualType(c, scope, qual_type, loc);
// Inner Node for the extern variable declaration
var node = try Tag.var_decl.create(c.arena, .{
.is_pub = false,
.is_const = is_const,
.is_extern = true,
.is_export = false,
.is_threadlocal = var_decl.getTLSKind() != .None, // TODO: Neccessary?
.linksection_string = null, // TODO: Neccessary?
.alignment = ClangAlignment.forVar(c, var_decl).zigAlignment(),
.name = extern_var_name,
.type = type_node,
.init = null,
});
// Outer Node for the wrapper struct
node = try Tag.extern_local_var.create(c.arena, .{ .name = mangled_name, .init = node });
try block_scope.statements.append(node);
try block_scope.discardVariable(c, mangled_name);
}
fn transDeclStmtOne(
c: *Context,
scope: *Scope,
decl: *const clang.Decl,
block_scope: *Scope.Block,
) TransError!void {
switch (decl.getKind()) {
.Var => {
const var_decl = @as(*const clang.VarDecl, @ptrCast(decl));
// Translation behavior for a block scope declared "extern" variable
// is enough of an outlier that it needs it's own function
if (var_decl.getStorageClass() == .Extern) {
return transLocalExternStmt(c, scope, var_decl, block_scope);
}
const decl_init = var_decl.getInit();
const loc = decl.getLocation();
const qual_type = var_decl.getTypeSourceInfo_getType();
const name = try c.str(@as(*const clang.NamedDecl, @ptrCast(var_decl)).getName_bytes_begin());
const mangled_name = try block_scope.makeMangledName(c, name);
if (qualTypeWasDemotedToOpaque(c, qual_type)) {
return fail(c, error.UnsupportedTranslation, loc, "local variable has opaque type", .{});
}
const is_static_local = var_decl.isStaticLocal();
const is_const = qual_type.isConstQualified();
const type_node = try transQualTypeMaybeInitialized(c, scope, qual_type, decl_init, loc);
var init_node = if (decl_init) |expr|
if (expr.getStmtClass() == .StringLiteralClass)
try transStringLiteralInitializer(c, @as(*const clang.StringLiteral, @ptrCast(expr)), type_node)
else
try transExprCoercing(c, scope, expr, .used)
else if (is_static_local)
try Tag.std_mem_zeroes.create(c.arena, type_node)
else
Tag.undefined_literal.init();
if (!qualTypeIsBoolean(qual_type) and isBoolRes(init_node)) {
init_node = try Tag.int_from_bool.create(c.arena, init_node);
} else if (init_node.tag() == .string_literal and qualTypeIsCharStar(qual_type)) {
const dst_type_node = try transQualType(c, scope, qual_type, loc);
init_node = try removeCVQualifiers(c, dst_type_node, init_node);
}
const var_name: []const u8 = if (is_static_local) Scope.Block.static_inner_name else mangled_name;
var node = try Tag.var_decl.create(c.arena, .{
.is_pub = false,
.is_const = is_const,
.is_extern = false,
.is_export = false,
.is_threadlocal = var_decl.getTLSKind() != .None,
.linksection_string = null,
.alignment = ClangAlignment.forVar(c, var_decl).zigAlignment(),
.name = var_name,
.type = type_node,
.init = init_node,
});
if (is_static_local) {
node = try Tag.static_local_var.create(c.arena, .{ .name = mangled_name, .init = node });
}
try block_scope.statements.append(node);
try block_scope.discardVariable(c, mangled_name);
const cleanup_attr = var_decl.getCleanupAttribute();
if (cleanup_attr) |fn_decl| {
const cleanup_fn_name = try c.str(@as(*const clang.NamedDecl, @ptrCast(fn_decl)).getName_bytes_begin());
const fn_id = try Tag.identifier.create(c.arena, cleanup_fn_name);
const varname = try Tag.identifier.create(c.arena, mangled_name);
const args = try c.arena.alloc(Node, 1);
args[0] = try Tag.address_of.create(c.arena, varname);
const cleanup_call = try Tag.call.create(c.arena, .{ .lhs = fn_id, .args = args });
const discard = try Tag.discard.create(c.arena, .{ .should_skip = false, .value = cleanup_call });
const deferred_cleanup = try Tag.@"defer".create(c.arena, discard);
try block_scope.statements.append(deferred_cleanup);
}
},
.Typedef => {
try transTypeDef(c, scope, @as(*const clang.TypedefNameDecl, @ptrCast(decl)));
},
.Record => {
try transRecordDecl(c, scope, @as(*const clang.RecordDecl, @ptrCast(decl)));
},
.Enum => {
try transEnumDecl(c, scope, @as(*const clang.EnumDecl, @ptrCast(decl)));
},
.Function => {
try transFnDecl(c, scope, @as(*const clang.FunctionDecl, @ptrCast(decl)));
},
else => {
const decl_name = try c.str(decl.getDeclKindName());
try warn(c, &c.global_scope.base, decl.getLocation(), "ignoring {s} declaration", .{decl_name});
},
}
}
fn transDeclStmt(c: *Context, scope: *Scope, stmt: *const clang.DeclStmt) TransError!Node {
const block_scope = try scope.findBlockScope(c);
var it = stmt.decl_begin();
const end_it = stmt.decl_end();
while (it != end_it) : (it += 1) {
try transDeclStmtOne(c, scope, it[0], block_scope);
}
return Tag.declaration.init();
}
fn transDeclRefExpr(
c: *Context,
scope: *Scope,
expr: *const clang.DeclRefExpr,
) TransError!Node {
const value_decl = expr.getDecl();
const name = try c.str(@as(*const clang.NamedDecl, @ptrCast(value_decl)).getName_bytes_begin());
const mangled_name = scope.getAlias(name);
const decl_is_var = @as(*const clang.Decl, @ptrCast(value_decl)).getKind() == .Var;
const storage_class = @as(*const clang.VarDecl, @ptrCast(value_decl)).getStorageClass();
const potential_local_extern = if (decl_is_var) ((storage_class == .Extern) and (scope.id != .root)) else false;
var confirmed_local_extern = false;
var confirmed_local_extern_fn = false;
var ref_expr = val: {
if (cIsFunctionDeclRef(@as(*const clang.Expr, @ptrCast(expr)))) {
if (scope.id != .root) {
if (scope.getLocalExternAlias(name)) |v| {
confirmed_local_extern_fn = true;
break :val try Tag.identifier.create(c.arena, v);
}
}
break :val try Tag.fn_identifier.create(c.arena, mangled_name);
} else if (potential_local_extern) {
if (scope.getLocalExternAlias(name)) |v| {
confirmed_local_extern = true;
break :val try Tag.identifier.create(c.arena, v);
} else {
break :val try Tag.identifier.create(c.arena, mangled_name);
}
} else {
break :val try Tag.identifier.create(c.arena, mangled_name);
}
};
if (decl_is_var) {
const var_decl = @as(*const clang.VarDecl, @ptrCast(value_decl));
if (var_decl.isStaticLocal()) {
ref_expr = try Tag.field_access.create(c.arena, .{
.lhs = ref_expr,
.field_name = Scope.Block.static_inner_name,
});
} else if (confirmed_local_extern) {
ref_expr = try Tag.field_access.create(c.arena, .{
.lhs = ref_expr,
.field_name = name, // by necessity, name will always == mangled_name
});
}
} else if (confirmed_local_extern_fn) {
ref_expr = try Tag.field_access.create(c.arena, .{
.lhs = ref_expr,
.field_name = name, // by necessity, name will always == mangled_name
});
}
scope.skipVariableDiscard(mangled_name);
return ref_expr;
}
fn transImplicitCastExpr(
c: *Context,
scope: *Scope,
expr: *const clang.ImplicitCastExpr,
result_used: ResultUsed,
) TransError!Node {
const sub_expr = expr.getSubExpr();
const dest_type = getExprQualType(c, @as(*const clang.Expr, @ptrCast(expr)));
const src_type = getExprQualType(c, sub_expr);
switch (expr.getCastKind()) {
.BitCast, .FloatingCast, .FloatingToIntegral, .IntegralToFloating, .IntegralCast, .PointerToIntegral, .IntegralToPointer => {
const sub_expr_node = try transExpr(c, scope, sub_expr, .used);
const casted = try transCCast(c, scope, expr.getBeginLoc(), dest_type, src_type, sub_expr_node);
return maybeSuppressResult(c, result_used, casted);
},
.LValueToRValue, .NoOp, .FunctionToPointerDecay => {
const sub_expr_node = try transExpr(c, scope, sub_expr, .used);
return maybeSuppressResult(c, result_used, sub_expr_node);
},
.ArrayToPointerDecay => {
const sub_expr_node = try transExpr(c, scope, sub_expr, .used);
if (exprIsNarrowStringLiteral(sub_expr) or exprIsFlexibleArrayRef(c, sub_expr)) {
return maybeSuppressResult(c, result_used, sub_expr_node);
}
const index_val = try Tag.integer_literal.create(c.arena, "0");
const index = try Tag.as.create(c.arena, .{
.lhs = try Tag.type.create(c.arena, "usize"),
.rhs = try Tag.int_cast.create(c.arena, index_val),
});
const array0_node = try Tag.array_access.create(c.arena, .{ .lhs = sub_expr_node, .rhs = index });
// Convert array to pointer by expression: addr = &sub_expr[0]
const addr = try Tag.address_of.create(c.arena, array0_node);
const casted = try transCPtrCast(c, scope, expr.getBeginLoc(), dest_type, src_type, addr);
return maybeSuppressResult(c, result_used, casted);
},
.NullToPointer => {
return Tag.null_literal.init();
},
.PointerToBoolean => {
// @intFromPtr(val) != 0
const ptr_node = try transExpr(c, scope, sub_expr, .used);
const int_from_ptr = try Tag.int_from_ptr.create(c.arena, ptr_node);
const ne = try Tag.not_equal.create(c.arena, .{ .lhs = int_from_ptr, .rhs = Tag.zero_literal.init() });
return maybeSuppressResult(c, result_used, ne);
},
.IntegralToBoolean, .FloatingToBoolean => {
const sub_expr_node = try transExpr(c, scope, sub_expr, .used);
// The expression is already a boolean one, return it as-is
if (isBoolRes(sub_expr_node))
return maybeSuppressResult(c, result_used, sub_expr_node);
// val != 0
const ne = try Tag.not_equal.create(c.arena, .{ .lhs = sub_expr_node, .rhs = Tag.zero_literal.init() });
return maybeSuppressResult(c, result_used, ne);
},
.BuiltinFnToFnPtr => {
return transBuiltinFnExpr(c, scope, sub_expr, result_used);
},
.ToVoid => {
// Should only appear in the rhs and lhs of a ConditionalOperator
return transExpr(c, scope, sub_expr, .unused);
},
else => |kind| return fail(
c,
error.UnsupportedTranslation,
@as(*const clang.Stmt, @ptrCast(expr)).getBeginLoc(),
"unsupported CastKind {s}",
.{@tagName(kind)},
),
}
}
fn isBuiltinDefined(name: []const u8) bool {
inline for (@typeInfo(std.zig.c_builtins).@"struct".decls) |decl| {
if (std.mem.eql(u8, name, decl.name)) return true;
}
return false;
}
fn transBuiltinFnExpr(c: *Context, scope: *Scope, expr: *const clang.Expr, used: ResultUsed) TransError!Node {
const node = try transExpr(c, scope, expr, used);
if (node.castTag(.fn_identifier)) |ident| {
const name = ident.data;
if (!isBuiltinDefined(name)) return fail(c, error.UnsupportedTranslation, expr.getBeginLoc(), "TODO implement function '{s}' in std.zig.c_builtins", .{name});
}
return node;
}
fn transBoolExpr(
c: *Context,
scope: *Scope,
expr: *const clang.Expr,
used: ResultUsed,
) TransError!Node {
if (@as(*const clang.Stmt, @ptrCast(expr)).getStmtClass() == .IntegerLiteralClass) {
var signum: c_int = undefined;
if (!(@as(*const clang.IntegerLiteral, @ptrCast(expr)).getSignum(&signum, c.clang_context))) {
return fail(c, error.UnsupportedTranslation, expr.getBeginLoc(), "invalid integer literal", .{});
}
const is_zero = signum == 0;
return Node{ .tag_if_small_enough = @intFromEnum(([2]Tag{ .true_literal, .false_literal })[@intFromBool(is_zero)]) };
}
const res = try transExpr(c, scope, expr, used);
if (isBoolRes(res)) {
return maybeSuppressResult(c, used, res);
}
const ty = getExprQualType(c, expr).getTypePtr();
const node = try finishBoolExpr(c, scope, expr.getBeginLoc(), ty, res, used);
return maybeSuppressResult(c, used, node);
}
fn exprIsBooleanType(expr: *const clang.Expr) bool {
return qualTypeIsBoolean(expr.getType());
}
fn exprIsNarrowStringLiteral(expr: *const clang.Expr) bool {
switch (expr.getStmtClass()) {
.StringLiteralClass => {
const string_lit = @as(*const clang.StringLiteral, @ptrCast(expr));
return string_lit.getCharByteWidth() == 1;
},
.PredefinedExprClass => return true,
.UnaryOperatorClass => {
const op_expr = @as(*const clang.UnaryOperator, @ptrCast(expr)).getSubExpr();
return exprIsNarrowStringLiteral(op_expr);
},
.ParenExprClass => {
const op_expr = @as(*const clang.ParenExpr, @ptrCast(expr)).getSubExpr();
return exprIsNarrowStringLiteral(op_expr);
},
.GenericSelectionExprClass => {
const gen_sel = @as(*const clang.GenericSelectionExpr, @ptrCast(expr));
return exprIsNarrowStringLiteral(gen_sel.getResultExpr());
},
else => return false,
}
}
fn exprIsFlexibleArrayRef(c: *Context, expr: *const clang.Expr) bool {
if (expr.getStmtClass() == .MemberExprClass) {
const member_expr = @as(*const clang.MemberExpr, @ptrCast(expr));
const member_decl = member_expr.getMemberDecl();
const decl_kind = @as(*const clang.Decl, @ptrCast(member_decl)).getKind();
if (decl_kind == .Field) {
const field_decl = @as(*const clang.FieldDecl, @ptrCast(member_decl));
return isFlexibleArrayFieldDecl(c, field_decl);
}
}
return false;
}
fn isBoolRes(res: Node) bool {
switch (res.tag()) {
.@"or",
.@"and",
.equal,
.not_equal,
.less_than,
.less_than_equal,
.greater_than,
.greater_than_equal,
.not,
.false_literal,
.true_literal,
=> return true,
else => return false,
}
}
fn finishBoolExpr(
c: *Context,
scope: *Scope,
loc: clang.SourceLocation,
ty: *const clang.Type,
node: Node,
used: ResultUsed,
) TransError!Node {
switch (ty.getTypeClass()) {
.Builtin => {
const builtin_ty = @as(*const clang.BuiltinType, @ptrCast(ty));
switch (builtin_ty.getKind()) {
.Bool => return node,
.Char_U,
.UChar,
.Char_S,
.SChar,
.UShort,
.UInt,
.ULong,
.ULongLong,
.Short,
.Int,
.Long,
.LongLong,
.UInt128,
.Int128,
.Float,
.Double,
.Float128,
.LongDouble,
.WChar_U,
.Char8,
.Char16,
.Char32,
.WChar_S,
.Float16,
=> {
// node != 0
return Tag.not_equal.create(c.arena, .{ .lhs = node, .rhs = Tag.zero_literal.init() });
},
.NullPtr => {
// node == null
return Tag.equal.create(c.arena, .{ .lhs = node, .rhs = Tag.null_literal.init() });
},
else => {},
}
},
.Pointer => {
if (node.tag() == .string_literal) {
// @intFromPtr(node) != 0
const int_from_ptr = try Tag.int_from_ptr.create(c.arena, node);
return Tag.not_equal.create(c.arena, .{ .lhs = int_from_ptr, .rhs = Tag.zero_literal.init() });
}
// node != null
return Tag.not_equal.create(c.arena, .{ .lhs = node, .rhs = Tag.null_literal.init() });
},
.Typedef => {
const typedef_ty = @as(*const clang.TypedefType, @ptrCast(ty));
const typedef_decl = typedef_ty.getDecl();
const underlying_type = typedef_decl.getUnderlyingType();
return finishBoolExpr(c, scope, loc, underlying_type.getTypePtr(), node, used);
},
.Enum => {
// node != 0
return Tag.not_equal.create(c.arena, .{ .lhs = node, .rhs = Tag.zero_literal.init() });
},
.Elaborated => {
const elaborated_ty = @as(*const clang.ElaboratedType, @ptrCast(ty));
const named_type = elaborated_ty.getNamedType();
return finishBoolExpr(c, scope, loc, named_type.getTypePtr(), node, used);
},
else => {},
}
return fail(c, error.UnsupportedType, loc, "unsupported bool expression type", .{});
}
const SuppressCast = enum {
with_as,
no_as,
};
fn transIntegerLiteral(
c: *Context,
scope: *Scope,
expr: *const clang.IntegerLiteral,
result_used: ResultUsed,
suppress_as: SuppressCast,
) TransError!Node {
var eval_result: clang.ExprEvalResult = undefined;
if (!expr.EvaluateAsInt(&eval_result, c.clang_context)) {
const loc = expr.getBeginLoc();
return fail(c, error.UnsupportedTranslation, loc, "invalid integer literal", .{});
}
if (suppress_as == .no_as) {
const int_lit_node = try transCreateNodeAPInt(c, eval_result.Val.getInt());
return maybeSuppressResult(c, result_used, int_lit_node);
}
// Integer literals in C have types, and this can matter for several reasons.
// For example, this is valid C:
// unsigned char y = 256;
// How this gets evaluated is the 256 is an integer, which gets truncated to signed char, then bit-casted
// to unsigned char, resulting in 0. In order for this to work, we have to emit this zig code:
// var y = @as(u8, @bitCast(@as(i8, @truncate(@as(c_int, 256)))));
// Ideally in translate-c we could flatten this out to simply:
// var y: u8 = 0;
// But the first step is to be correct, and the next step is to make the output more elegant.
// @as(T, x)
const expr_base = @as(*const clang.Expr, @ptrCast(expr));
const ty_node = try transQualType(c, scope, expr_base.getType(), expr_base.getBeginLoc());
const rhs = try transCreateNodeAPInt(c, eval_result.Val.getInt());
const as = try Tag.as.create(c.arena, .{ .lhs = ty_node, .rhs = rhs });
return maybeSuppressResult(c, result_used, as);
}
fn transReturnStmt(
c: *Context,
scope: *Scope,
expr: *const clang.ReturnStmt,
) TransError!Node {
const val_expr = expr.getRetValue() orelse
return Tag.return_void.init();
var rhs = try transExprCoercing(c, scope, val_expr, .used);
const return_qt = scope.findBlockReturnType();
if (isBoolRes(rhs) and !qualTypeIsBoolean(return_qt)) {
rhs = try Tag.int_from_bool.create(c.arena, rhs);
}
return Tag.@"return".create(c.arena, rhs);
}
fn transNarrowStringLiteral(
c: *Context,
stmt: *const clang.StringLiteral,
result_used: ResultUsed,
) TransError!Node {
var len: usize = undefined;
const bytes_ptr = stmt.getString_bytes_begin_size(&len);
const str = try std.fmt.allocPrint(c.arena, "\"{f}\"", .{std.zig.fmtString(bytes_ptr[0..len])});
const node = try Tag.string_literal.create(c.arena, str);
return maybeSuppressResult(c, result_used, node);
}
fn transStringLiteral(
c: *Context,
scope: *Scope,
stmt: *const clang.StringLiteral,
result_used: ResultUsed,
) TransError!Node {
const kind = stmt.getKind();
switch (kind) {
.Ascii, .UTF8 => return transNarrowStringLiteral(c, stmt, result_used),
.UTF16, .UTF32, .Wide => {
const str_type = @tagName(stmt.getKind());
const name = try std.fmt.allocPrint(c.arena, "zig.{s}_string_{d}", .{ str_type, c.getMangle() });
const expr_base = @as(*const clang.Expr, @ptrCast(stmt));
const array_type = try transQualTypeInitialized(c, scope, expr_base.getType(), expr_base, expr_base.getBeginLoc());
const lit_array = try transStringLiteralInitializer(c, stmt, array_type);
const decl = try Tag.var_simple.create(c.arena, .{ .name = name, .init = lit_array });
try scope.appendNode(decl);
const node = try Tag.identifier.create(c.arena, name);
return maybeSuppressResult(c, result_used, node);
},
}
}
fn getArrayPayload(array_type: Node) ast.Payload.Array.ArrayTypeInfo {
return (array_type.castTag(.array_type) orelse array_type.castTag(.null_sentinel_array_type).?).data;
}
/// Translate a string literal that is initializing an array. In general narrow string
/// literals become `"<string>".*` or `"<string>"[0..<size>].*` if they need truncation.
/// Wide string literals become an array of integers. zero-fillers pad out the array to
/// the appropriate length, if necessary.
fn transStringLiteralInitializer(
c: *Context,
stmt: *const clang.StringLiteral,
array_type: Node,
) TransError!Node {
assert(array_type.tag() == .array_type or array_type.tag() == .null_sentinel_array_type);
const is_narrow = stmt.getKind() == .Ascii or stmt.getKind() == .UTF8;
const str_length = stmt.getLength();
const payload = getArrayPayload(array_type);
const array_size = payload.len;
const elem_type = payload.elem_type;
if (array_size == 0) return Tag.empty_array.create(c.arena, elem_type);
const num_inits = @min(str_length, array_size);
const init_node = if (num_inits > 0) blk: {
if (is_narrow) {
// "string literal".* or string literal"[0..num_inits].*
var str = try transNarrowStringLiteral(c, stmt, .used);
if (str_length != array_size) str = try Tag.string_slice.create(c.arena, .{ .string = str, .end = num_inits });
break :blk try Tag.deref.create(c.arena, str);
} else {
const init_list = try c.arena.alloc(Node, num_inits);
var i: c_uint = 0;
while (i < num_inits) : (i += 1) {
init_list[i] = try transCreateCharLitNode(c, false, stmt.getCodeUnit(i));
}
const init_args: ast.Payload.Array.ArrayTypeInfo = .{ .len = num_inits, .elem_type = elem_type };
const init_array_type = if (array_type.tag() == .array_type)
try Tag.array_type.create(c.arena, init_args)
else
try Tag.null_sentinel_array_type.create(c.arena, init_args);
break :blk try Tag.array_init.create(c.arena, .{
.cond = init_array_type,
.cases = init_list,
});
}
} else null;
if (num_inits == array_size) return init_node.?; // init_node is only null if num_inits == 0; but if num_inits == array_size == 0 we've already returned
assert(array_size > str_length); // If array_size <= str_length, `num_inits == array_size` and we've already returned.
const filler_node = try Tag.array_filler.create(c.arena, .{
.type = elem_type,
.filler = Tag.zero_literal.init(),
.count = array_size - str_length,
});
if (init_node) |some| {
return Tag.array_cat.create(c.arena, .{ .lhs = some, .rhs = filler_node });
} else {
return filler_node;
}
}
/// determine whether `stmt` is a "pointer subtraction expression" - a subtraction where
/// both operands resolve to addresses. The C standard requires that both operands
/// point to elements of the same array object, but we do not verify that here.
fn cIsPointerDiffExpr(stmt: *const clang.BinaryOperator) bool {
const lhs = @as(*const clang.Stmt, @ptrCast(stmt.getLHS()));
const rhs = @as(*const clang.Stmt, @ptrCast(stmt.getRHS()));
return stmt.getOpcode() == .Sub and
qualTypeIsPtr(@as(*const clang.Expr, @ptrCast(lhs)).getType()) and
qualTypeIsPtr(@as(*const clang.Expr, @ptrCast(rhs)).getType());
}
fn cIsEnum(qt: clang.QualType) bool {
return qt.getCanonicalType().getTypeClass() == .Enum;
}
fn cIsVector(qt: clang.QualType) bool {
return qt.getCanonicalType().getTypeClass() == .Vector;
}
/// Get the underlying int type of an enum. The C compiler chooses a signed int
/// type that is large enough to hold all of the enum's values. It is not required
/// to be the smallest possible type that can hold all the values.
fn cIntTypeForEnum(enum_qt: clang.QualType) clang.QualType {
assert(cIsEnum(enum_qt));
const ty = enum_qt.getCanonicalType().getTypePtr();
const enum_ty = @as(*const clang.EnumType, @ptrCast(ty));
const enum_decl = enum_ty.getDecl();
return enum_decl.getIntegerType();
}
// when modifying this function, make sure to also update std.zig.c_translation.cast
fn transCCast(
c: *Context,
scope: *Scope,
loc: clang.SourceLocation,
dst_type: clang.QualType,
src_type: clang.QualType,
expr: Node,
) !Node {
if (qualTypeCanon(dst_type).isVoidType()) return expr;
if (dst_type.eq(src_type)) return expr;
if (qualTypeIsPtr(dst_type) and qualTypeIsPtr(src_type))
return transCPtrCast(c, scope, loc, dst_type, src_type, expr);
if (cIsEnum(dst_type)) return transCCast(c, scope, loc, cIntTypeForEnum(dst_type), src_type, expr);
if (cIsEnum(src_type)) return transCCast(c, scope, loc, dst_type, cIntTypeForEnum(src_type), expr);
const dst_node = try transQualType(c, scope, dst_type, loc);
if (cIsInteger(dst_type) and cIsInteger(src_type)) {
// 1. If src_type is an enum, determine the underlying signed int type
// 2. Extend or truncate without changing signed-ness.
// 3. Bit-cast to correct signed-ness
const src_type_is_signed = cIsSignedInteger(src_type);
var src_int_expr = expr;
if (isBoolRes(src_int_expr)) {
src_int_expr = try Tag.int_from_bool.create(c.arena, src_int_expr);
return Tag.as.create(c.arena, .{ .lhs = dst_node, .rhs = src_int_expr });
}
switch (cIntTypeCmp(dst_type, src_type)) {
.lt => {
// @truncate(SameSignSmallerInt, src_int_expr)
const ty_node = try transQualTypeIntWidthOf(c, dst_type, src_type_is_signed);
src_int_expr = try Tag.as.create(c.arena, .{
.lhs = ty_node,
.rhs = try Tag.truncate.create(c.arena, src_int_expr),
});
},
.gt => {
// @as(SameSignBiggerInt, src_int_expr)
const ty_node = try transQualTypeIntWidthOf(c, dst_type, src_type_is_signed);
src_int_expr = try Tag.as.create(c.arena, .{ .lhs = ty_node, .rhs = src_int_expr });
},
.eq => {
// src_int_expr = src_int_expr
},
}
// @as(dest_type, @bitCast(intermediate_value))
return Tag.as.create(c.arena, .{
.lhs = dst_node,
.rhs = try Tag.bit_cast.create(c.arena, src_int_expr),
});
}
if (cIsVector(src_type) or cIsVector(dst_type)) {
// C cast where at least 1 operand is a vector requires them to be same size
// @as(dest_type, @bitCast(val))
return Tag.as.create(c.arena, .{
.lhs = dst_node,
.rhs = try Tag.bit_cast.create(c.arena, expr),
});
}
if (cIsInteger(dst_type) and qualTypeIsPtr(src_type)) {
// @intCast(dest_type, @intFromPtr(val))
const int_from_ptr = try Tag.int_from_ptr.create(c.arena, expr);
return Tag.as.create(c.arena, .{
.lhs = dst_node,
.rhs = try Tag.int_cast.create(c.arena, int_from_ptr),
});
}
if (cIsInteger(src_type) and qualTypeIsPtr(dst_type)) {
// @as(dest_type, @ptrFromInt(val))
return Tag.as.create(c.arena, .{
.lhs = dst_node,
.rhs = try Tag.ptr_from_int.create(c.arena, expr),
});
}
if (cIsFloating(src_type) and cIsFloating(dst_type)) {
// @as(dest_type, @floatCast(val))
return Tag.as.create(c.arena, .{
.lhs = dst_node,
.rhs = try Tag.float_cast.create(c.arena, expr),
});
}
if (cIsFloating(src_type) and !cIsFloating(dst_type)) {
// bool expression: floating val != 0
if (qualTypeIsBoolean(dst_type)) {
return Tag.not_equal.create(c.arena, .{
.lhs = expr,
.rhs = Tag.zero_literal.init(),
});
}
// @as(dest_type, @intFromFloat(val))
return Tag.as.create(c.arena, .{
.lhs = dst_node,
.rhs = try Tag.int_from_float.create(c.arena, expr),
});
}
if (!cIsFloating(src_type) and cIsFloating(dst_type)) {
var rhs = expr;
if (qualTypeIsBoolean(src_type) or isBoolRes(rhs)) rhs = try Tag.int_from_bool.create(c.arena, expr);
// @as(dest_type, @floatFromInt(val))
return Tag.as.create(c.arena, .{
.lhs = dst_node,
.rhs = try Tag.float_from_int.create(c.arena, rhs),
});
}
if (qualTypeIsBoolean(src_type) and !qualTypeIsBoolean(dst_type)) {
// @intFromBool returns a u1
// TODO: if dst_type is 1 bit & signed (bitfield) we need @bitCast
// instead of @as
const int_from_bool = try Tag.int_from_bool.create(c.arena, expr);
return Tag.as.create(c.arena, .{ .lhs = dst_node, .rhs = int_from_bool });
}
// @as(dest_type, val)
return Tag.as.create(c.arena, .{ .lhs = dst_node, .rhs = expr });
}
fn transExpr(c: *Context, scope: *Scope, expr: *const clang.Expr, used: ResultUsed) TransError!Node {
return transStmt(c, scope, @as(*const clang.Stmt, @ptrCast(expr)), used);
}
/// Same as `transExpr` but with the knowledge that the operand will be type coerced, and therefore
/// an `@as` would be redundant. This is used to prevent redundant `@as` in integer literals.
fn transExprCoercing(c: *Context, scope: *Scope, expr: *const clang.Expr, used: ResultUsed) TransError!Node {
switch (@as(*const clang.Stmt, @ptrCast(expr)).getStmtClass()) {
.IntegerLiteralClass => {
return transIntegerLiteral(c, scope, @as(*const clang.IntegerLiteral, @ptrCast(expr)), .used, .no_as);
},
.CharacterLiteralClass => {
return transCharLiteral(c, scope, @as(*const clang.CharacterLiteral, @ptrCast(expr)), .used, .no_as);
},
.UnaryOperatorClass => {
const un_expr = @as(*const clang.UnaryOperator, @ptrCast(expr));
if (un_expr.getOpcode() == .Extension) {
return transExprCoercing(c, scope, un_expr.getSubExpr(), used);
}
},
.ImplicitCastExprClass => {
const cast_expr = @as(*const clang.ImplicitCastExpr, @ptrCast(expr));
const sub_expr = cast_expr.getSubExpr();
switch (@as(*const clang.Stmt, @ptrCast(sub_expr)).getStmtClass()) {
.IntegerLiteralClass, .CharacterLiteralClass => switch (cast_expr.getCastKind()) {
.IntegralToFloating => return transExprCoercing(c, scope, sub_expr, used),
.IntegralCast => {
const dest_type = getExprQualType(c, expr);
if (literalFitsInType(c, sub_expr, dest_type))
return transExprCoercing(c, scope, sub_expr, used);
},
else => {},
},
else => {},
}
},
else => {},
}
return transExpr(c, scope, expr, .used);
}
fn literalFitsInType(c: *Context, expr: *const clang.Expr, qt: clang.QualType) bool {
var width = qualTypeIntBitWidth(c, qt) catch 8;
if (width == 0) width = 8; // Byte is the smallest type.
const is_signed = cIsSignedInteger(qt);
const width_max_int = (@as(u64, 1) << math.lossyCast(u6, width - @intFromBool(is_signed))) - 1;
switch (@as(*const clang.Stmt, @ptrCast(expr)).getStmtClass()) {
.CharacterLiteralClass => {
const char_lit = @as(*const clang.CharacterLiteral, @ptrCast(expr));
const val = char_lit.getValue();
// If the val is less than the max int then it fits.
return val <= width_max_int;
},
.IntegerLiteralClass => {
const int_lit = @as(*const clang.IntegerLiteral, @ptrCast(expr));
var eval_result: clang.ExprEvalResult = undefined;
if (!int_lit.EvaluateAsInt(&eval_result, c.clang_context)) {
return false;
}
const int = eval_result.Val.getInt();
return int.lessThanEqual(width_max_int);
},
else => unreachable,
}
}
fn transInitListExprRecord(
c: *Context,
scope: *Scope,
loc: clang.SourceLocation,
expr: *const clang.InitListExpr,
ty: *const clang.Type,
) TransError!Node {
var is_union_type = false;
// Unions and Structs are both represented as RecordDecl
const record_ty = ty.getAsRecordType() orelse
blk: {
is_union_type = true;
break :blk ty.getAsUnionType();
} orelse unreachable;
const record_decl = record_ty.getDecl();
const record_def = record_decl.getDefinition() orelse
unreachable;
const ty_node = try transType(c, scope, ty, loc);
const init_count = expr.getNumInits();
var field_inits = std.array_list.Managed(ast.Payload.ContainerInit.Initializer).init(c.gpa);
defer field_inits.deinit();
if (init_count == 0) {
const source_loc = @as(*const clang.Expr, @ptrCast(expr)).getBeginLoc();
return transZeroInitExpr(c, scope, source_loc, ty);
}
var init_i: c_uint = 0;
var it = record_def.field_begin();
const end_it = record_def.field_end();
while (it.neq(end_it)) : (it = it.next()) {
const field_decl = it.deref();
// The initializer for a union type has a single entry only
if (is_union_type and field_decl != expr.getInitializedFieldInUnion()) {
continue;
}
assert(init_i < init_count);
const elem_expr = expr.getInit(init_i);
init_i += 1;
// Generate the field assignment expression:
// .field_name = expr
var raw_name = try c.str(@as(*const clang.NamedDecl, @ptrCast(field_decl)).getName_bytes_begin());
if (field_decl.isAnonymousStructOrUnion()) {
const name = c.decl_table.get(@intFromPtr(field_decl.getCanonicalDecl())).?;
raw_name = try c.arena.dupe(u8, name);
}
var init_expr = try transExpr(c, scope, elem_expr, .used);
const field_qt = field_decl.getType();
if (init_expr.tag() == .string_literal and qualTypeIsCharStar(field_qt)) {
if (scope.id == .root) {
init_expr = try stringLiteralToCharStar(c, init_expr);
} else {
const dst_type_node = try transQualType(c, scope, field_qt, loc);
init_expr = try removeCVQualifiers(c, dst_type_node, init_expr);
}
}
try field_inits.append(.{
.name = raw_name,
.value = init_expr,
});
}
if (ty_node.castTag(.identifier)) |ident_node| {
scope.skipVariableDiscard(ident_node.data);
}
return Tag.container_init.create(c.arena, .{
.lhs = ty_node,
.inits = try c.arena.dupe(ast.Payload.ContainerInit.Initializer, field_inits.items),
});
}
fn transInitListExprArray(
c: *Context,
scope: *Scope,
loc: clang.SourceLocation,
expr: *const clang.InitListExpr,
ty: *const clang.Type,
) TransError!Node {
const arr_type = ty.getAsArrayTypeUnsafe();
const child_qt = arr_type.getElementType();
const child_type = try transQualType(c, scope, child_qt, loc);
const init_count = expr.getNumInits();
assert(@as(*const clang.Type, @ptrCast(arr_type)).isConstantArrayType());
const const_arr_ty = @as(*const clang.ConstantArrayType, @ptrCast(arr_type));
var size_ap_int: *const clang.APInt = undefined;
const_arr_ty.getSize(&size_ap_int);
defer size_ap_int.free();
const all_count = size_ap_int.getLimitedValue(usize);
const leftover_count = all_count - init_count;
if (all_count == 0) {
return Tag.empty_array.create(c.arena, child_type);
}
if (expr.isStringLiteralInit()) {
assert(init_count == 1);
const init_expr = expr.getInit(0);
const string_literal = init_expr.castToStringLiteral().?;
return try transStringLiteral(c, scope, string_literal, .used);
}
const init_node = if (init_count != 0) blk: {
const init_list = try c.arena.alloc(Node, init_count);
for (init_list, 0..) |*init, i| {
const elem_expr = expr.getInit(@as(c_uint, @intCast(i)));
init.* = try transExprCoercing(c, scope, elem_expr, .used);
}
const init_node = try Tag.array_init.create(c.arena, .{
.cond = try Tag.array_type.create(c.arena, .{ .len = init_count, .elem_type = child_type }),
.cases = init_list,
});
if (leftover_count == 0) {
return init_node;
}
break :blk init_node;
} else null;
assert(expr.hasArrayFiller());
const filler_val_expr = expr.getArrayFiller();
const filler_node = try Tag.array_filler.create(c.arena, .{
.type = child_type,
.filler = try transExprCoercing(c, scope, filler_val_expr, .used),
.count = leftover_count,
});
if (init_node) |some| {
return Tag.array_cat.create(c.arena, .{ .lhs = some, .rhs = filler_node });
} else {
return filler_node;
}
}
fn transInitListExprVector(
c: *Context,
scope: *Scope,
loc: clang.SourceLocation,
expr: *const clang.InitListExpr,
) TransError!Node {
const qt = getExprQualType(c, @as(*const clang.Expr, @ptrCast(expr)));
const vector_ty = @as(*const clang.VectorType, @ptrCast(qualTypeCanon(qt)));
const init_count = expr.getNumInits();
const num_elements = vector_ty.getNumElements();
const element_qt = vector_ty.getElementType();
if (init_count == 0) {
const vec_node = try Tag.vector.create(c.arena, .{
.lhs = try transCreateNodeNumber(c, num_elements, .int),
.rhs = try transQualType(c, scope, element_qt, loc),
});
return Tag.as.create(c.arena, .{
.lhs = vec_node,
.rhs = try Tag.vector_zero_init.create(c.arena, Tag.zero_literal.init()),
});
}
const vector_type = try transQualType(c, scope, qt, loc);
var block_scope = try Scope.Block.init(c, scope, true);
defer block_scope.deinit();
// workaround for https://github.com/ziglang/zig/issues/8322
// we store the initializers in temp variables and use those
// to initialize the vector. Eventually we can just directly
// construct the init_list from casted source members
var i: usize = 0;
while (i < init_count) : (i += 1) {
const mangled_name = try block_scope.makeMangledName(c, "tmp");
const init_expr = expr.getInit(@as(c_uint, @intCast(i)));
const tmp_decl_node = try Tag.var_simple.create(c.arena, .{
.name = mangled_name,
.init = try transExpr(c, &block_scope.base, init_expr, .used),
});
try block_scope.statements.append(tmp_decl_node);
}
const init_list = try c.arena.alloc(Node, num_elements);
for (init_list, 0..) |*init, init_index| {
if (init_index < init_count) {
const tmp_decl = block_scope.statements.items[init_index];
const name = tmp_decl.castTag(.var_simple).?.data.name;
init.* = try Tag.identifier.create(c.arena, name);
} else {
init.* = Tag.undefined_literal.init();
}
}
const array_init = try Tag.array_init.create(c.arena, .{
.cond = vector_type,
.cases = init_list,
});
const break_node = try Tag.break_val.create(c.arena, .{
.label = block_scope.label,
.val = array_init,
});
try block_scope.statements.append(break_node);
return block_scope.complete(c);
}
fn transInitListExpr(
c: *Context,
scope: *Scope,
expr: *const clang.InitListExpr,
used: ResultUsed,
) TransError!Node {
const qt = getExprQualType(c, @as(*const clang.Expr, @ptrCast(expr)));
var qual_type = qt.getTypePtr();
const source_loc = @as(*const clang.Expr, @ptrCast(expr)).getBeginLoc();
if (qualTypeWasDemotedToOpaque(c, qt)) {
return fail(c, error.UnsupportedTranslation, source_loc, "cannot initialize opaque type", .{});
}
if (qual_type.isRecordType()) {
return maybeSuppressResult(c, used, try transInitListExprRecord(
c,
scope,
source_loc,
expr,
qual_type,
));
} else if (qual_type.isArrayType()) {
return maybeSuppressResult(c, used, try transInitListExprArray(
c,
scope,
source_loc,
expr,
qual_type,
));
} else if (qual_type.isVectorType()) {
return maybeSuppressResult(c, used, try transInitListExprVector(c, scope, source_loc, expr));
} else {
const type_name = try c.str(qual_type.getTypeClassName());
return fail(c, error.UnsupportedType, source_loc, "unsupported initlist type: '{s}'", .{type_name});
}
}
fn transZeroInitExpr(
c: *Context,
scope: *Scope,
source_loc: clang.SourceLocation,
ty: *const clang.Type,
) TransError!Node {
switch (ty.getTypeClass()) {
.Builtin => {
const builtin_ty = @as(*const clang.BuiltinType, @ptrCast(ty));
switch (builtin_ty.getKind()) {
.Bool => return Tag.false_literal.init(),
.Char_U,
.UChar,
.Char_S,
.Char8,
.SChar,
.UShort,
.UInt,
.ULong,
.ULongLong,
.Short,
.Int,
.Long,
.LongLong,
.UInt128,
.Int128,
.Float,
.Double,
.Float128,
.Float16,
.LongDouble,
=> return Tag.zero_literal.init(),
else => return fail(c, error.UnsupportedType, source_loc, "unsupported builtin type", .{}),
}
},
.Pointer => return Tag.null_literal.init(),
.Typedef => {
const typedef_ty = @as(*const clang.TypedefType, @ptrCast(ty));
const typedef_decl = typedef_ty.getDecl();
return transZeroInitExpr(
c,
scope,
source_loc,
typedef_decl.getUnderlyingType().getTypePtr(),
);
},
else => return Tag.std_mem_zeroes.create(c.arena, try transType(c, scope, ty, source_loc)),
}
}
fn transImplicitValueInitExpr(
c: *Context,
scope: *Scope,
expr: *const clang.Expr,
) TransError!Node {
const source_loc = expr.getBeginLoc();
const qt = getExprQualType(c, expr);
const ty = qt.getTypePtr();
return transZeroInitExpr(c, scope, source_loc, ty);
}
/// If a statement can possibly translate to a Zig assignment (either directly because it's
/// an assignment in C or indirectly via result assignment to `_`) AND it's the sole statement
/// in the body of an if statement or loop, then we need to put the statement into its own block.
/// The `else` case here corresponds to statements that could result in an assignment. If a statement
/// class never needs a block, add its enum to the top prong.
fn maybeBlockify(c: *Context, scope: *Scope, stmt: *const clang.Stmt) TransError!Node {
switch (stmt.getStmtClass()) {
.BreakStmtClass,
.CompoundStmtClass,
.ContinueStmtClass,
.DeclRefExprClass,
.DeclStmtClass,
.DoStmtClass,
.ForStmtClass,
.IfStmtClass,
.ReturnStmtClass,
.NullStmtClass,
.WhileStmtClass,
=> return transStmt(c, scope, stmt, .unused),
else => return blockify(c, scope, stmt),
}
}
fn blockify(c: *Context, scope: *Scope, stmt: *const clang.Stmt) TransError!Node {
var block_scope = try Scope.Block.init(c, scope, false);
defer block_scope.deinit();
const result = try transStmt(c, &block_scope.base, stmt, .unused);
try block_scope.statements.append(result);
return block_scope.complete(c);
}
fn transIfStmt(
c: *Context,
scope: *Scope,
stmt: *const clang.IfStmt,
) TransError!Node {
// if (c) t
// if (c) t else e
var cond_scope = Scope.Condition{
.base = .{
.parent = scope,
.id = .condition,
},
};
defer cond_scope.deinit();
const cond_expr = @as(*const clang.Expr, @ptrCast(stmt.getCond()));
const cond = try transBoolExpr(c, &cond_scope.base, cond_expr, .used);
const then_stmt = stmt.getThen();
const else_stmt = stmt.getElse();
const then_class = then_stmt.getStmtClass();
// block needed to keep else statement from attaching to inner while
const must_blockify = (else_stmt != null) and switch (then_class) {
.DoStmtClass, .ForStmtClass, .WhileStmtClass => true,
else => false,
};
const then_body = if (must_blockify)
try blockify(c, scope, then_stmt)
else
try maybeBlockify(c, scope, then_stmt);
const else_body = if (else_stmt) |expr|
try maybeBlockify(c, scope, expr)
else
null;
return Tag.@"if".create(c.arena, .{ .cond = cond, .then = then_body, .@"else" = else_body });
}
fn transWhileLoop(
c: *Context,
scope: *Scope,
stmt: *const clang.WhileStmt,
) TransError!Node {
var cond_scope = Scope.Condition{
.base = .{
.parent = scope,
.id = .condition,
},
};
defer cond_scope.deinit();
const cond_expr = @as(*const clang.Expr, @ptrCast(stmt.getCond()));
const cond = try transBoolExpr(c, &cond_scope.base, cond_expr, .used);
var loop_scope = Scope{
.parent = scope,
.id = .loop,
};
const body = try maybeBlockify(c, &loop_scope, stmt.getBody());
return Tag.@"while".create(c.arena, .{ .cond = cond, .body = body, .cont_expr = null });
}
fn transDoWhileLoop(
c: *Context,
scope: *Scope,
stmt: *const clang.DoStmt,
) TransError!Node {
var loop_scope = Scope{
.parent = scope,
.id = .do_loop,
};
// if (!cond) break;
var cond_scope = Scope.Condition{
.base = .{
.parent = scope,
.id = .condition,
},
};
defer cond_scope.deinit();
const cond = try transBoolExpr(c, &cond_scope.base, @as(*const clang.Expr, @ptrCast(stmt.getCond())), .used);
const if_not_break = switch (cond.tag()) {
.true_literal => {
const body_node = try maybeBlockify(c, scope, stmt.getBody());
return Tag.while_true.create(c.arena, body_node);
},
else => try Tag.if_not_break.create(c.arena, cond),
};
var body_node = try transStmt(c, &loop_scope, stmt.getBody(), .unused);
if (body_node.isNoreturn(true)) {
// The body node ends in a noreturn statement. Simply put it in a while (true)
// in case it contains breaks or continues.
} else if (stmt.getBody().getStmtClass() == .CompoundStmtClass) {
// there's already a block in C, so we'll append our condition to it.
// c: do {
// c: a;
// c: b;
// c: } while(c);
// zig: while (true) {
// zig: a;
// zig: b;
// zig: if (!cond) break;
// zig: }
const block = body_node.castTag(.block).?;
block.data.stmts.len += 1; // This is safe since we reserve one extra space in Scope.Block.complete.
block.data.stmts[block.data.stmts.len - 1] = if_not_break;
} else {
// the C statement is without a block, so we need to create a block to contain it.
// c: do
// c: a;
// c: while(c);
// zig: while (true) {
// zig: a;
// zig: if (!cond) break;
// zig: }
const statements = try c.arena.alloc(Node, 2);
statements[0] = body_node;
statements[1] = if_not_break;
body_node = try Tag.block.create(c.arena, .{ .label = null, .stmts = statements });
}
return Tag.while_true.create(c.arena, body_node);
}
fn transForLoop(
c: *Context,
scope: *Scope,
stmt: *const clang.ForStmt,
) TransError!Node {
var loop_scope = Scope{
.parent = scope,
.id = .loop,
};
var block_scope: ?Scope.Block = null;
defer if (block_scope) |*bs| bs.deinit();
if (stmt.getInit()) |init| {
block_scope = try Scope.Block.init(c, scope, false);
loop_scope.parent = &block_scope.?.base;
const init_node = try transStmt(c, &block_scope.?.base, init, .unused);
if (init_node.tag() != .declaration) try block_scope.?.statements.append(init_node);
}
var cond_scope = Scope.Condition{
.base = .{
.parent = &loop_scope,
.id = .condition,
},
};
defer cond_scope.deinit();
const cond = if (stmt.getCond()) |cond|
try transBoolExpr(c, &cond_scope.base, cond, .used)
else
Tag.true_literal.init();
const cont_expr = if (stmt.getInc()) |incr|
try transExpr(c, &cond_scope.base, incr, .unused)
else
null;
const body = try maybeBlockify(c, &loop_scope, stmt.getBody());
const while_node = try Tag.@"while".create(c.arena, .{ .cond = cond, .body = body, .cont_expr = cont_expr });
if (block_scope) |*bs| {
try bs.statements.append(while_node);
return try bs.complete(c);
} else {
return while_node;
}
}
fn transSwitch(
c: *Context,
scope: *Scope,
stmt: *const clang.SwitchStmt,
) TransError!Node {
var loop_scope = Scope{
.parent = scope,
.id = .loop,
};
var block_scope = try Scope.Block.init(c, &loop_scope, false);
defer block_scope.deinit();
const base_scope = &block_scope.base;
var cond_scope = Scope.Condition{
.base = .{
.parent = base_scope,
.id = .condition,
},
};
defer cond_scope.deinit();
const switch_expr = try transExpr(c, &cond_scope.base, stmt.getCond(), .used);
var cases = std.array_list.Managed(Node).init(c.gpa);
defer cases.deinit();
var has_default = false;
const body = stmt.getBody();
assert(body.getStmtClass() == .CompoundStmtClass);
const compound_stmt = @as(*const clang.CompoundStmt, @ptrCast(body));
var it = compound_stmt.body_begin();
const end_it = compound_stmt.body_end();
// Iterate over switch body and collect all cases.
// Fallthrough is handled by duplicating statements.
while (it != end_it) : (it += 1) {
switch (it[0].getStmtClass()) {
.CaseStmtClass => {
var items = std.array_list.Managed(Node).init(c.gpa);
defer items.deinit();
const sub = try transCaseStmt(c, base_scope, it[0], &items);
const res = try transSwitchProngStmt(c, base_scope, sub, it, end_it);
if (items.items.len == 0) {
has_default = true;
const switch_else = try Tag.switch_else.create(c.arena, res);
try cases.append(switch_else);
} else {
const switch_prong = try Tag.switch_prong.create(c.arena, .{
.cases = try c.arena.dupe(Node, items.items),
.cond = res,
});
try cases.append(switch_prong);
}
},
.DefaultStmtClass => {
has_default = true;
const default_stmt = @as(*const clang.DefaultStmt, @ptrCast(it[0]));
var sub = default_stmt.getSubStmt();
while (true) switch (sub.getStmtClass()) {
.CaseStmtClass => sub = @as(*const clang.CaseStmt, @ptrCast(sub)).getSubStmt(),
.DefaultStmtClass => sub = @as(*const clang.DefaultStmt, @ptrCast(sub)).getSubStmt(),
else => break,
};
const res = try transSwitchProngStmt(c, base_scope, sub, it, end_it);
const switch_else = try Tag.switch_else.create(c.arena, res);
try cases.append(switch_else);
},
else => {}, // collected in transSwitchProngStmt
}
}
if (!has_default) {
const else_prong = try Tag.switch_else.create(c.arena, Tag.empty_block.init());
try cases.append(else_prong);
}
const switch_node = try Tag.@"switch".create(c.arena, .{
.cond = switch_expr,
.cases = try c.arena.dupe(Node, cases.items),
});
try block_scope.statements.append(switch_node);
try block_scope.statements.append(Tag.@"break".init());
const while_body = try block_scope.complete(c);
return Tag.while_true.create(c.arena, while_body);
}
/// Collects all items for this case, returns the first statement after the labels.
/// If items ends up empty, the prong should be translated as an else.
fn transCaseStmt(c: *Context, scope: *Scope, stmt: *const clang.Stmt, items: *std.array_list.Managed(Node)) TransError!*const clang.Stmt {
var sub = stmt;
var seen_default = false;
while (true) {
switch (sub.getStmtClass()) {
.DefaultStmtClass => {
seen_default = true;
items.items.len = 0;
const default_stmt = @as(*const clang.DefaultStmt, @ptrCast(sub));
sub = default_stmt.getSubStmt();
},
.CaseStmtClass => {
const case_stmt = @as(*const clang.CaseStmt, @ptrCast(sub));
if (seen_default) {
items.items.len = 0;
sub = case_stmt.getSubStmt();
continue;
}
const expr = if (case_stmt.getRHS()) |rhs| blk: {
const lhs_node = try transExprCoercing(c, scope, case_stmt.getLHS(), .used);
const rhs_node = try transExprCoercing(c, scope, rhs, .used);
break :blk try Tag.ellipsis3.create(c.arena, .{ .lhs = lhs_node, .rhs = rhs_node });
} else try transExprCoercing(c, scope, case_stmt.getLHS(), .used);
try items.append(expr);
sub = case_stmt.getSubStmt();
},
else => return sub,
}
}
}
/// Collects all statements seen by this case into a block.
/// Avoids creating a block if the first statement is a break or return.
fn transSwitchProngStmt(
c: *Context,
scope: *Scope,
stmt: *const clang.Stmt,
parent_it: clang.CompoundStmt.ConstBodyIterator,
parent_end_it: clang.CompoundStmt.ConstBodyIterator,
) TransError!Node {
switch (stmt.getStmtClass()) {
.BreakStmtClass => return Tag.@"break".init(),
.ReturnStmtClass => return transStmt(c, scope, stmt, .unused),
.CaseStmtClass, .DefaultStmtClass => unreachable,
else => {
var block_scope = try Scope.Block.init(c, scope, false);
defer block_scope.deinit();
// we do not need to translate `stmt` since it is the first stmt of `parent_it`
try transSwitchProngStmtInline(c, &block_scope, parent_it, parent_end_it);
return try block_scope.complete(c);
},
}
}
/// Collects all statements seen by this case into a block.
fn transSwitchProngStmtInline(
c: *Context,
block: *Scope.Block,
start_it: clang.CompoundStmt.ConstBodyIterator,
end_it: clang.CompoundStmt.ConstBodyIterator,
) TransError!void {
var it = start_it;
while (it != end_it) : (it += 1) {
switch (it[0].getStmtClass()) {
.ReturnStmtClass => {
const result = try transStmt(c, &block.base, it[0], .unused);
try block.statements.append(result);
return;
},
.BreakStmtClass => {
try block.statements.append(Tag.@"break".init());
return;
},
.CaseStmtClass => {
var sub = @as(*const clang.CaseStmt, @ptrCast(it[0])).getSubStmt();
while (true) switch (sub.getStmtClass()) {
.CaseStmtClass => sub = @as(*const clang.CaseStmt, @ptrCast(sub)).getSubStmt(),
.DefaultStmtClass => sub = @as(*const clang.DefaultStmt, @ptrCast(sub)).getSubStmt(),
else => break,
};
const result = try transStmt(c, &block.base, sub, .unused);
assert(result.tag() != .declaration);
try block.statements.append(result);
if (result.isNoreturn(true)) {
return;
}
},
.DefaultStmtClass => {
var sub = @as(*const clang.DefaultStmt, @ptrCast(it[0])).getSubStmt();
while (true) switch (sub.getStmtClass()) {
.CaseStmtClass => sub = @as(*const clang.CaseStmt, @ptrCast(sub)).getSubStmt(),
.DefaultStmtClass => sub = @as(*const clang.DefaultStmt, @ptrCast(sub)).getSubStmt(),
else => break,
};
const result = try transStmt(c, &block.base, sub, .unused);
assert(result.tag() != .declaration);
try block.statements.append(result);
if (result.isNoreturn(true)) {
return;
}
},
.CompoundStmtClass => {
const result = try transCompoundStmt(c, &block.base, @as(*const clang.CompoundStmt, @ptrCast(it[0])));
try block.statements.append(result);
if (result.isNoreturn(true)) {
return;
}
},
else => {
const result = try transStmt(c, &block.base, it[0], .unused);
switch (result.tag()) {
.declaration, .empty_block => {},
else => try block.statements.append(result),
}
},
}
}
return;
}
fn transConstantExpr(c: *Context, scope: *Scope, expr: *const clang.Expr, used: ResultUsed) TransError!Node {
var result: clang.ExprEvalResult = undefined;
if (!expr.evaluateAsConstantExpr(&result, .Normal, c.clang_context))
return fail(c, error.UnsupportedTranslation, expr.getBeginLoc(), "invalid constant expression", .{});
switch (result.Val.getKind()) {
.Int => {
// See comment in `transIntegerLiteral` for why this code is here.
// @as(T, x)
const expr_base = @as(*const clang.Expr, @ptrCast(expr));
const as_node = try Tag.as.create(c.arena, .{
.lhs = try transQualType(c, scope, expr_base.getType(), expr_base.getBeginLoc()),
.rhs = try transCreateNodeAPInt(c, result.Val.getInt()),
});
return maybeSuppressResult(c, used, as_node);
},
else => |kind| {
return fail(c, error.UnsupportedTranslation, expr.getBeginLoc(), "unsupported constant expression kind '{}'", .{kind});
},
}
}
fn transPredefinedExpr(c: *Context, scope: *Scope, expr: *const clang.PredefinedExpr, used: ResultUsed) TransError!Node {
return transStringLiteral(c, scope, expr.getFunctionName(), used);
}
fn transCreateCharLitNode(c: *Context, narrow: bool, val: u32) TransError!Node {
return Tag.char_literal.create(c.arena, if (narrow)
try std.fmt.allocPrint(c.arena, "'{f}'", .{std.zig.fmtChar(@intCast(val))})
else
try std.fmt.allocPrint(c.arena, "'\\u{{{x}}}'", .{val}));
}
fn transCharLiteral(
c: *Context,
scope: *Scope,
stmt: *const clang.CharacterLiteral,
result_used: ResultUsed,
suppress_as: SuppressCast,
) TransError!Node {
const kind = stmt.getKind();
const val = stmt.getValue();
const narrow = kind == .Ascii or kind == .UTF8;
// C has a somewhat obscure feature called multi-character character constant
// e.g. 'abcd'
const int_lit_node = if (kind == .Ascii and val > 255)
try transCreateNodeNumber(c, val, .int)
else
try transCreateCharLitNode(c, narrow, val);
if (suppress_as == .no_as) {
return maybeSuppressResult(c, result_used, int_lit_node);
}
// See comment in `transIntegerLiteral` for why this code is here.
// @as(T, x)
const expr_base = @as(*const clang.Expr, @ptrCast(stmt));
const as_node = try Tag.as.create(c.arena, .{
.lhs = try transQualType(c, scope, expr_base.getType(), expr_base.getBeginLoc()),
.rhs = int_lit_node,
});
return maybeSuppressResult(c, result_used, as_node);
}
fn transStmtExpr(c: *Context, scope: *Scope, stmt: *const clang.StmtExpr, used: ResultUsed) TransError!Node {
const comp = stmt.getSubStmt();
if (used == .unused) {
return transCompoundStmt(c, scope, comp);
}
var block_scope = try Scope.Block.init(c, scope, true);
defer block_scope.deinit();
var it = comp.body_begin();
const end_it = comp.body_end();
while (it != end_it - 1) : (it += 1) {
const result = try transStmt(c, &block_scope.base, it[0], .unused);
switch (result.tag()) {
.declaration, .empty_block => {},
else => try block_scope.statements.append(result),
}
}
const last_result = try transStmt(c, &block_scope.base, it[0], .used);
switch (last_result.tag()) {
.declaration, .empty_block => {},
else => {
const break_node = try Tag.break_val.create(c.arena, .{
.label = block_scope.label,
.val = last_result,
});
try block_scope.statements.append(break_node);
},
}
const res = try block_scope.complete(c);
return maybeSuppressResult(c, used, res);
}
fn transMemberExpr(c: *Context, scope: *Scope, stmt: *const clang.MemberExpr, result_used: ResultUsed) TransError!Node {
var container_node = try transExpr(c, scope, stmt.getBase(), .used);
if (stmt.isArrow()) {
container_node = try Tag.deref.create(c.arena, container_node);
}
const member_decl = stmt.getMemberDecl();
const name = blk: {
const decl_kind = @as(*const clang.Decl, @ptrCast(member_decl)).getKind();
// If we're referring to a anonymous struct/enum find the bogus name
// we've assigned to it during the RecordDecl translation
if (decl_kind == .Field) {
const field_decl = @as(*const clang.FieldDecl, @ptrCast(member_decl));
if (field_decl.isAnonymousStructOrUnion()) {
const name = c.decl_table.get(@intFromPtr(field_decl.getCanonicalDecl())).?;
break :blk try c.arena.dupe(u8, name);
}
}
const decl = @as(*const clang.NamedDecl, @ptrCast(member_decl));
break :blk try c.str(decl.getName_bytes_begin());
};
var node = try Tag.field_access.create(c.arena, .{ .lhs = container_node, .field_name = name });
if (exprIsFlexibleArrayRef(c, @as(*const clang.Expr, @ptrCast(stmt)))) {
node = try Tag.call.create(c.arena, .{ .lhs = node, .args = &.{} });
}
return maybeSuppressResult(c, result_used, node);
}
/// ptr[subscr] (`subscr` is a signed integer expression, `ptr` a pointer) becomes:
/// (blk: {
/// const tmp = subscr;
/// if (tmp >= 0) break :blk ptr + @intCast(usize, tmp) else break :blk ptr - ~@bitCast(usize, @intCast(isize, tmp) +% -1);
/// }).*
/// Todo: rip this out once `[*]T + isize` becomes valid.
fn transSignedArrayAccess(
c: *Context,
scope: *Scope,
container_expr: *const clang.Expr,
subscr_expr: *const clang.Expr,
result_used: ResultUsed,
) TransError!Node {
var block_scope = try Scope.Block.init(c, scope, true);
defer block_scope.deinit();
const tmp = try block_scope.makeMangledName(c, "tmp");
const subscr_node = try transExpr(c, &block_scope.base, subscr_expr, .used);
const subscr_decl = try Tag.var_simple.create(c.arena, .{ .name = tmp, .init = subscr_node });
try block_scope.statements.append(subscr_decl);
const tmp_ref = try Tag.identifier.create(c.arena, tmp);
const container_node = try transExpr(c, &block_scope.base, container_expr, .used);
const cond_node = try Tag.greater_than_equal.create(c.arena, .{ .lhs = tmp_ref, .rhs = Tag.zero_literal.init() });
const then_value = try Tag.add.create(c.arena, .{
.lhs = container_node,
.rhs = try Tag.as.create(c.arena, .{
.lhs = try Tag.type.create(c.arena, "usize"),
.rhs = try Tag.int_cast.create(c.arena, tmp_ref),
}),
});
const then_body = try Tag.break_val.create(c.arena, .{
.label = block_scope.label,
.val = then_value,
});
const minuend = container_node;
const signed_size = try Tag.as.create(c.arena, .{
.lhs = try Tag.type.create(c.arena, "isize"),
.rhs = try Tag.int_cast.create(c.arena, tmp_ref),
});
const to_cast = try Tag.add_wrap.create(c.arena, .{
.lhs = signed_size,
.rhs = try Tag.negate.create(c.arena, Tag.one_literal.init()),
});
const bitcast_node = try Tag.as.create(c.arena, .{
.lhs = try Tag.type.create(c.arena, "usize"),
.rhs = try Tag.bit_cast.create(c.arena, to_cast),
});
const subtrahend = try Tag.bit_not.create(c.arena, bitcast_node);
const difference = try Tag.sub.create(c.arena, .{
.lhs = minuend,
.rhs = subtrahend,
});
const else_body = try Tag.break_val.create(c.arena, .{
.label = block_scope.label,
.val = difference,
});
const if_node = try Tag.@"if".create(c.arena, .{
.cond = cond_node,
.then = then_body,
.@"else" = else_body,
});
try block_scope.statements.append(if_node);
const block_node = try block_scope.complete(c);
const derefed = try Tag.deref.create(c.arena, block_node);
return maybeSuppressResult(c, result_used, derefed);
}
fn transArrayAccess(c: *Context, scope: *Scope, stmt: *const clang.ArraySubscriptExpr, result_used: ResultUsed) TransError!Node {
const base_stmt = stmt.getBase();
const base_qt = getExprQualType(c, base_stmt);
const is_vector = cIsVector(base_qt);
const subscr_expr = stmt.getIdx();
const subscr_qt = getExprQualType(c, subscr_expr);
const is_longlong = cIsLongLongInteger(subscr_qt);
const is_signed = cIsSignedInteger(subscr_qt);
const is_nonnegative_int_literal = cIsNonNegativeIntLiteral(c, subscr_expr);
// Unwrap the base statement if it's an array decayed to a bare pointer type
// so that we index the array itself
var unwrapped_base = base_stmt;
if (@as(*const clang.Stmt, @ptrCast(base_stmt)).getStmtClass() == .ImplicitCastExprClass) {
const implicit_cast = @as(*const clang.ImplicitCastExpr, @ptrCast(base_stmt));
if (implicit_cast.getCastKind() == .ArrayToPointerDecay) {
unwrapped_base = implicit_cast.getSubExpr();
}
}
// Special case: actual pointer (not decayed array) and signed integer subscript
// See discussion at https://github.com/ziglang/zig/pull/8589
if (is_signed and (base_stmt == unwrapped_base) and !is_vector and !is_nonnegative_int_literal)
return transSignedArrayAccess(c, scope, base_stmt, subscr_expr, result_used);
const container_node = try transExpr(c, scope, unwrapped_base, .used);
const rhs = if (is_longlong or is_signed) blk: {
// check if long long first so that signed long long doesn't just become unsigned long long
const typeid_node = if (is_longlong) try Tag.type.create(c.arena, "usize") else try transQualTypeIntWidthOf(c, subscr_qt, false);
break :blk try Tag.as.create(c.arena, .{
.lhs = typeid_node,
.rhs = try Tag.int_cast.create(
c.arena,
try transExpr(c, scope, subscr_expr, .used),
),
});
} else try transExpr(c, scope, subscr_expr, .used);
const node = try Tag.array_access.create(c.arena, .{
.lhs = container_node,
.rhs = rhs,
});
return maybeSuppressResult(c, result_used, node);
}
/// Check if an expression is ultimately a reference to a function declaration
/// (which means it should not be unwrapped with `.?` in translated code)
fn cIsFunctionDeclRef(expr: *const clang.Expr) bool {
switch (expr.getStmtClass()) {
.ParenExprClass => {
const op_expr = @as(*const clang.ParenExpr, @ptrCast(expr)).getSubExpr();
return cIsFunctionDeclRef(op_expr);
},
.DeclRefExprClass => {
const decl_ref = @as(*const clang.DeclRefExpr, @ptrCast(expr));
const value_decl = decl_ref.getDecl();
const qt = value_decl.getType();
return qualTypeChildIsFnProto(qt);
},
.ImplicitCastExprClass => {
const implicit_cast = @as(*const clang.ImplicitCastExpr, @ptrCast(expr));
const cast_kind = implicit_cast.getCastKind();
if (cast_kind == .BuiltinFnToFnPtr) return true;
if (cast_kind == .FunctionToPointerDecay) {
return cIsFunctionDeclRef(implicit_cast.getSubExpr());
}
return false;
},
.UnaryOperatorClass => {
const un_op = @as(*const clang.UnaryOperator, @ptrCast(expr));
const opcode = un_op.getOpcode();
return (opcode == .AddrOf or opcode == .Deref) and cIsFunctionDeclRef(un_op.getSubExpr());
},
.GenericSelectionExprClass => {
const gen_sel = @as(*const clang.GenericSelectionExpr, @ptrCast(expr));
return cIsFunctionDeclRef(gen_sel.getResultExpr());
},
else => return false,
}
}
fn transCallExpr(c: *Context, scope: *Scope, stmt: *const clang.CallExpr, result_used: ResultUsed) TransError!Node {
const callee = stmt.getCallee();
const raw_fn_expr = try transExpr(c, scope, callee, .used);
var is_ptr = false;
const fn_ty = qualTypeGetFnProto(callee.getType(), &is_ptr);
const fn_expr = if (is_ptr and fn_ty != null and !cIsFunctionDeclRef(callee))
try Tag.unwrap.create(c.arena, raw_fn_expr)
else
raw_fn_expr;
const num_args = stmt.getNumArgs();
const args = try c.arena.alloc(Node, num_args);
const c_args = stmt.getArgs();
var i: usize = 0;
while (i < num_args) : (i += 1) {
var arg = try transExpr(c, scope, c_args[i], .used);
// In C the result type of a boolean expression is int. If this result is passed as
// an argument to a function whose parameter is also int, there is no cast. Therefore
// in Zig we'll need to cast it from bool to u1 (which will safely coerce to c_int).
if (fn_ty) |ty| {
switch (ty) {
.Proto => |fn_proto| {
const param_count = fn_proto.getNumParams();
if (i < param_count) {
const param_qt = fn_proto.getParamType(@as(c_uint, @intCast(i)));
if (isBoolRes(arg) and cIsNativeInt(param_qt)) {
arg = try Tag.int_from_bool.create(c.arena, arg);
} else if (arg.tag() == .string_literal and qualTypeIsCharStar(param_qt)) {
const loc = @as(*const clang.Stmt, @ptrCast(stmt)).getBeginLoc();
const dst_type_node = try transQualType(c, scope, param_qt, loc);
arg = try removeCVQualifiers(c, dst_type_node, arg);
}
}
},
else => {},
}
}
args[i] = arg;
}
const node = try Tag.call.create(c.arena, .{ .lhs = fn_expr, .args = args });
if (fn_ty) |ty| {
const canon = ty.getReturnType().getCanonicalType();
const ret_ty = canon.getTypePtr();
if (ret_ty.isVoidType()) {
return node;
}
}
return maybeSuppressResult(c, result_used, node);
}
const ClangFunctionType = union(enum) {
Proto: *const clang.FunctionProtoType,
NoProto: *const clang.FunctionType,
fn getReturnType(self: @This()) clang.QualType {
switch (@as(meta.Tag(@This()), self)) {
.Proto => return self.Proto.getReturnType(),
.NoProto => return self.NoProto.getReturnType(),
}
}
};
fn qualTypeGetFnProto(qt: clang.QualType, is_ptr: *bool) ?ClangFunctionType {
const canon = qt.getCanonicalType();
var ty = canon.getTypePtr();
is_ptr.* = false;
if (ty.getTypeClass() == .Pointer) {
is_ptr.* = true;
const child_qt = ty.getPointeeType();
ty = child_qt.getTypePtr();
}
if (ty.getTypeClass() == .FunctionProto) {
return ClangFunctionType{ .Proto = @as(*const clang.FunctionProtoType, @ptrCast(ty)) };
}
if (ty.getTypeClass() == .FunctionNoProto) {
return ClangFunctionType{ .NoProto = @as(*const clang.FunctionType, @ptrCast(ty)) };
}
return null;
}
fn transUnaryExprOrTypeTraitExpr(
c: *Context,
scope: *Scope,
stmt: *const clang.UnaryExprOrTypeTraitExpr,
result_used: ResultUsed,
) TransError!Node {
const loc = stmt.getBeginLoc();
const type_node = try transQualType(c, scope, stmt.getTypeOfArgument(), loc);
const kind = stmt.getKind();
const node = switch (kind) {
.SizeOf => try Tag.sizeof.create(c.arena, type_node),
.AlignOf => try Tag.alignof.create(c.arena, type_node),
.DataSizeOf,
.PreferredAlignOf,
.PtrAuthTypeDiscriminator,
.VecStep,
.OpenMPRequiredSimdAlign,
=> return fail(
c,
error.UnsupportedTranslation,
loc,
"unsupported type trait kind {}",
.{kind},
),
};
return maybeSuppressResult(c, result_used, node);
}
fn qualTypeHasWrappingOverflow(qt: clang.QualType) bool {
if (cIsUnsignedInteger(qt)) {
// unsigned integer overflow wraps around.
return true;
} else {
// float, signed integer, and pointer overflow is undefined behavior.
return false;
}
}
fn transUnaryOperator(c: *Context, scope: *Scope, stmt: *const clang.UnaryOperator, used: ResultUsed) TransError!Node {
const op_expr = stmt.getSubExpr();
switch (stmt.getOpcode()) {
.PostInc => if (qualTypeHasWrappingOverflow(stmt.getType()))
return transCreatePostCrement(c, scope, stmt, .add_wrap_assign, used)
else
return transCreatePostCrement(c, scope, stmt, .add_assign, used),
.PostDec => if (qualTypeHasWrappingOverflow(stmt.getType()))
return transCreatePostCrement(c, scope, stmt, .sub_wrap_assign, used)
else
return transCreatePostCrement(c, scope, stmt, .sub_assign, used),
.PreInc => if (qualTypeHasWrappingOverflow(stmt.getType()))
return transCreatePreCrement(c, scope, stmt, .add_wrap_assign, used)
else
return transCreatePreCrement(c, scope, stmt, .add_assign, used),
.PreDec => if (qualTypeHasWrappingOverflow(stmt.getType()))
return transCreatePreCrement(c, scope, stmt, .sub_wrap_assign, used)
else
return transCreatePreCrement(c, scope, stmt, .sub_assign, used),
.AddrOf => {
return Tag.address_of.create(c.arena, try transExpr(c, scope, op_expr, used));
},
.Deref => {
if (qualTypeWasDemotedToOpaque(c, stmt.getType()))
return fail(c, error.UnsupportedTranslation, stmt.getBeginLoc(), "cannot dereference opaque type", .{});
const node = try transExpr(c, scope, op_expr, used);
var is_ptr = false;
const fn_ty = qualTypeGetFnProto(op_expr.getType(), &is_ptr);
if (fn_ty != null and is_ptr)
return node;
return Tag.deref.create(c.arena, node);
},
.Plus => return transExpr(c, scope, op_expr, used),
.Minus => {
if (!qualTypeHasWrappingOverflow(op_expr.getType())) {
const sub_expr_node = try transExpr(c, scope, op_expr, .used);
const to_negate = if (isBoolRes(sub_expr_node)) blk: {
const ty_node = try Tag.type.create(c.arena, "c_int");
const int_node = try Tag.int_from_bool.create(c.arena, sub_expr_node);
break :blk try Tag.as.create(c.arena, .{ .lhs = ty_node, .rhs = int_node });
} else sub_expr_node;
return Tag.negate.create(c.arena, to_negate);
} else if (cIsUnsignedInteger(op_expr.getType())) {
// use -% x for unsigned integers
return Tag.negate_wrap.create(c.arena, try transExpr(c, scope, op_expr, .used));
} else return fail(c, error.UnsupportedTranslation, stmt.getBeginLoc(), "C negation with non float non integer", .{});
},
.Not => {
return Tag.bit_not.create(c.arena, try transExpr(c, scope, op_expr, .used));
},
.LNot => {
return Tag.not.create(c.arena, try transBoolExpr(c, scope, op_expr, .used));
},
.Extension => {
return transExpr(c, scope, stmt.getSubExpr(), used);
},
else => return fail(c, error.UnsupportedTranslation, stmt.getBeginLoc(), "unsupported C translation {}", .{stmt.getOpcode()}),
}
}
fn transCreatePreCrement(
c: *Context,
scope: *Scope,
stmt: *const clang.UnaryOperator,
op: Tag,
used: ResultUsed,
) TransError!Node {
const op_expr = stmt.getSubExpr();
if (used == .unused) {
// common case
// c: ++expr
// zig: expr += 1
const lhs = try transExpr(c, scope, op_expr, .used);
const rhs = Tag.one_literal.init();
return transCreateNodeInfixOp(c, op, lhs, rhs, .used);
}
// worst case
// c: ++expr
// zig: (blk: {
// zig: const _ref = &expr;
// zig: _ref.* += 1;
// zig: break :blk _ref.*
// zig: })
var block_scope = try Scope.Block.init(c, scope, true);
defer block_scope.deinit();
const ref = try block_scope.reserveMangledName(c, "ref");
const expr = try transExpr(c, &block_scope.base, op_expr, .used);
const addr_of = try Tag.address_of.create(c.arena, expr);
const ref_decl = try Tag.var_simple.create(c.arena, .{ .name = ref, .init = addr_of });
try block_scope.statements.append(ref_decl);
const lhs_node = try Tag.identifier.create(c.arena, ref);
const ref_node = try Tag.deref.create(c.arena, lhs_node);
const node = try transCreateNodeInfixOp(c, op, ref_node, Tag.one_literal.init(), .used);
try block_scope.statements.append(node);
const break_node = try Tag.break_val.create(c.arena, .{
.label = block_scope.label,
.val = ref_node,
});
try block_scope.statements.append(break_node);
return block_scope.complete(c);
}
fn transCreatePostCrement(
c: *Context,
scope: *Scope,
stmt: *const clang.UnaryOperator,
op: Tag,
used: ResultUsed,
) TransError!Node {
const op_expr = stmt.getSubExpr();
if (used == .unused) {
// common case
// c: expr++
// zig: expr += 1
const lhs = try transExpr(c, scope, op_expr, .used);
const rhs = Tag.one_literal.init();
return transCreateNodeInfixOp(c, op, lhs, rhs, .used);
}
// worst case
// c: expr++
// zig: (blk: {
// zig: const _ref = &expr;
// zig: const _tmp = _ref.*;
// zig: _ref.* += 1;
// zig: break :blk _tmp
// zig: })
var block_scope = try Scope.Block.init(c, scope, true);
defer block_scope.deinit();
const ref = try block_scope.reserveMangledName(c, "ref");
const tmp = try block_scope.reserveMangledName(c, "tmp");
const expr = try transExpr(c, &block_scope.base, op_expr, .used);
const addr_of = try Tag.address_of.create(c.arena, expr);
const ref_decl = try Tag.var_simple.create(c.arena, .{ .name = ref, .init = addr_of });
try block_scope.statements.append(ref_decl);
const lhs_node = try Tag.identifier.create(c.arena, ref);
const ref_node = try Tag.deref.create(c.arena, lhs_node);
const tmp_decl = try Tag.var_simple.create(c.arena, .{ .name = tmp, .init = ref_node });
try block_scope.statements.append(tmp_decl);
const node = try transCreateNodeInfixOp(c, op, ref_node, Tag.one_literal.init(), .used);
try block_scope.statements.append(node);
const break_node = try Tag.break_val.create(c.arena, .{
.label = block_scope.label,
.val = try Tag.identifier.create(c.arena, tmp),
});
try block_scope.statements.append(break_node);
return block_scope.complete(c);
}
fn transCompoundAssignOperator(c: *Context, scope: *Scope, stmt: *const clang.CompoundAssignOperator, used: ResultUsed) TransError!Node {
switch (stmt.getOpcode()) {
.MulAssign => if (qualTypeHasWrappingOverflow(stmt.getType()))
return transCreateCompoundAssign(c, scope, stmt, .mul_wrap_assign, used)
else
return transCreateCompoundAssign(c, scope, stmt, .mul_assign, used),
.AddAssign => if (qualTypeHasWrappingOverflow(stmt.getType()))
return transCreateCompoundAssign(c, scope, stmt, .add_wrap_assign, used)
else
return transCreateCompoundAssign(c, scope, stmt, .add_assign, used),
.SubAssign => if (qualTypeHasWrappingOverflow(stmt.getType()))
return transCreateCompoundAssign(c, scope, stmt, .sub_wrap_assign, used)
else
return transCreateCompoundAssign(c, scope, stmt, .sub_assign, used),
.DivAssign => return transCreateCompoundAssign(c, scope, stmt, .div_assign, used),
.RemAssign => return transCreateCompoundAssign(c, scope, stmt, .mod_assign, used),
.ShlAssign => return transCreateCompoundAssign(c, scope, stmt, .shl_assign, used),
.ShrAssign => return transCreateCompoundAssign(c, scope, stmt, .shr_assign, used),
.AndAssign => return transCreateCompoundAssign(c, scope, stmt, .bit_and_assign, used),
.XorAssign => return transCreateCompoundAssign(c, scope, stmt, .bit_xor_assign, used),
.OrAssign => return transCreateCompoundAssign(c, scope, stmt, .bit_or_assign, used),
else => return fail(
c,
error.UnsupportedTranslation,
stmt.getBeginLoc(),
"unsupported C translation {}",
.{stmt.getOpcode()},
),
}
}
fn transCreateCompoundAssign(
c: *Context,
scope: *Scope,
stmt: *const clang.CompoundAssignOperator,
op: Tag,
used: ResultUsed,
) TransError!Node {
const is_shift = op == .shl_assign or op == .shr_assign;
const is_div = op == .div_assign;
const is_mod = op == .mod_assign;
const lhs = stmt.getLHS();
const rhs = stmt.getRHS();
const loc = stmt.getBeginLoc();
const lhs_qt = getExprQualType(c, lhs);
const rhs_qt = getExprQualType(c, rhs);
const is_signed = cIsSignedInteger(lhs_qt);
const is_ptr_arithmetic = qualTypeIsPtr(lhs_qt) and cIsInteger(rhs_qt);
const is_ptr_op_signed = qualTypeIsPtr(lhs_qt) and cIsSignedInteger(rhs_qt);
const requires_cast = !lhs_qt.eq(rhs_qt) and !is_ptr_arithmetic;
if (used == .unused) {
// common case
// c: lhs += rhs
// zig: lhs += rhs
const lhs_node = try transExpr(c, scope, lhs, .used);
var rhs_node = try transExpr(c, scope, rhs, .used);
if (is_ptr_op_signed) rhs_node = try usizeCastForWrappingPtrArithmetic(c.arena, rhs_node);
if ((is_mod or is_div) and is_signed) {
if (requires_cast) rhs_node = try transCCast(c, scope, loc, lhs_qt, rhs_qt, rhs_node);
const operands: @FieldType(ast.Payload.BinOp, "data") = .{ .lhs = lhs_node, .rhs = rhs_node };
const builtin = if (is_mod)
try Tag.signed_remainder.create(c.arena, operands)
else
try Tag.div_trunc.create(c.arena, operands);
return transCreateNodeInfixOp(c, .assign, lhs_node, builtin, .used);
}
if (is_shift) {
rhs_node = try Tag.int_cast.create(c.arena, rhs_node);
} else if (requires_cast) {
rhs_node = try transCCast(c, scope, loc, lhs_qt, rhs_qt, rhs_node);
}
return transCreateNodeInfixOp(c, op, lhs_node, rhs_node, .used);
}
// worst case
// c: lhs += rhs
// zig: (blk: {
// zig: const _ref = &lhs;
// zig: _ref.* += rhs;
// zig: break :blk _ref.*
// zig: })
var block_scope = try Scope.Block.init(c, scope, true);
defer block_scope.deinit();
const ref = try block_scope.reserveMangledName(c, "ref");
const expr = try transExpr(c, &block_scope.base, lhs, .used);
const addr_of = try Tag.address_of.create(c.arena, expr);
const ref_decl = try Tag.var_simple.create(c.arena, .{ .name = ref, .init = addr_of });
try block_scope.statements.append(ref_decl);
const lhs_node = try Tag.identifier.create(c.arena, ref);
const ref_node = try Tag.deref.create(c.arena, lhs_node);
var rhs_node = try transExpr(c, &block_scope.base, rhs, .used);
if (is_ptr_op_signed) rhs_node = try usizeCastForWrappingPtrArithmetic(c.arena, rhs_node);
if ((is_mod or is_div) and is_signed) {
if (requires_cast) rhs_node = try transCCast(c, scope, loc, lhs_qt, rhs_qt, rhs_node);
const operands: @FieldType(ast.Payload.BinOp, "data") = .{ .lhs = ref_node, .rhs = rhs_node };
const builtin = if (is_mod)
try Tag.signed_remainder.create(c.arena, operands)
else
try Tag.div_trunc.create(c.arena, operands);
const assign = try transCreateNodeInfixOp(c, .assign, ref_node, builtin, .used);
try block_scope.statements.append(assign);
} else {
if (is_shift) {
rhs_node = try Tag.int_cast.create(c.arena, rhs_node);
} else if (requires_cast) {
rhs_node = try transCCast(c, &block_scope.base, loc, lhs_qt, rhs_qt, rhs_node);
}
const assign = try transCreateNodeInfixOp(c, op, ref_node, rhs_node, .used);
try block_scope.statements.append(assign);
}
const break_node = try Tag.break_val.create(c.arena, .{
.label = block_scope.label,
.val = ref_node,
});
try block_scope.statements.append(break_node);
return block_scope.complete(c);
}
fn removeCVQualifiers(c: *Context, dst_type_node: Node, expr: Node) Error!Node {
const volatile_casted = try Tag.volatile_cast.create(c.arena, expr);
const const_casted = try Tag.const_cast.create(c.arena, volatile_casted);
return Tag.as.create(c.arena, .{
.lhs = dst_type_node,
.rhs = try Tag.ptr_cast.create(c.arena, const_casted),
});
}
fn transCPtrCast(
c: *Context,
scope: *Scope,
loc: clang.SourceLocation,
dst_type: clang.QualType,
src_type: clang.QualType,
expr: Node,
) !Node {
const ty = dst_type.getTypePtr();
const child_type = ty.getPointeeType();
const src_ty = src_type.getTypePtr();
const src_child_type = src_ty.getPointeeType();
const dst_type_node = try transType(c, scope, ty, loc);
if (!src_ty.isArrayType() and ((src_child_type.isConstQualified() and
!child_type.isConstQualified()) or
(src_child_type.isVolatileQualified() and
!child_type.isVolatileQualified())))
{
return removeCVQualifiers(c, dst_type_node, expr);
} else {
// Implicit downcasting from higher to lower alignment values is forbidden,
// use @alignCast to side-step this problem
const rhs = if (qualTypeCanon(child_type).isVoidType())
// void has 1-byte alignment, so @alignCast is not needed
expr
else if (typeIsOpaque(c, qualTypeCanon(child_type), loc))
// For opaque types a ptrCast is enough
expr
else blk: {
break :blk try Tag.align_cast.create(c.arena, expr);
};
return Tag.as.create(c.arena, .{
.lhs = dst_type_node,
.rhs = try Tag.ptr_cast.create(c.arena, rhs),
});
}
}
fn transFloatingLiteral(c: *Context, expr: *const clang.FloatingLiteral, used: ResultUsed) TransError!Node {
// TODO use something more accurate than widening to a larger float type and printing that result
switch (expr.getRawSemantics()) {
.IEEEhalf, // f16
.IEEEsingle, // f32
.IEEEdouble, // f64
=> {
var dbl = expr.getValueAsApproximateDouble();
const is_negative = dbl < 0; // -0.0 is considered non-negative
if (is_negative) dbl = -dbl;
const str = if (dbl == @floor(dbl))
try std.fmt.allocPrint(c.arena, "{d}.0", .{dbl})
else
try std.fmt.allocPrint(c.arena, "{d}", .{dbl});
var node = try Tag.float_literal.create(c.arena, str);
if (is_negative) node = try Tag.negate.create(c.arena, node);
return maybeSuppressResult(c, used, node);
},
.x87DoubleExtended, // f80
.IEEEquad, // f128
=> return transFloatingLiteralQuad(c, expr, used),
else => |format| return fail(
c,
error.UnsupportedTranslation,
expr.getBeginLoc(),
"unsupported floating point constant format {}",
.{format},
),
}
}
fn transFloatingLiteralQuad(c: *Context, expr: *const clang.FloatingLiteral, used: ResultUsed) TransError!Node {
assert(switch (expr.getRawSemantics()) {
.x87DoubleExtended, .IEEEquad => true,
else => false,
});
var low: u64 = undefined;
var high: u64 = undefined;
expr.getValueAsApproximateQuadBits(&low, &high);
var quad: f128 = @bitCast(low | @as(u128, high) << 64);
const is_negative = quad < 0; // -0.0 is considered non-negative
if (is_negative) quad = -quad;
// TODO implement decimal format for f128 <https://github.com/ziglang/zig/issues/1181>
// in the meantime, if the value can be roundtripped by casting it to f64, serializing it to
// the decimal format and parsing it back as the exact same f128 value, then use that serialized form
const str = fmt_decimal: {
var buf: [512]u8 = undefined; // should be large enough to print any f64 in decimal form
const dbl: f64 = @floatCast(quad);
const temp_str = if (dbl == @floor(dbl))
std.fmt.bufPrint(&buf, "{d}.0", .{dbl}) catch |err| switch (err) {
error.NoSpaceLeft => unreachable,
}
else
std.fmt.bufPrint(&buf, "{d}", .{dbl}) catch |err| switch (err) {
error.NoSpaceLeft => unreachable,
};
const could_roundtrip = if (std.fmt.parseFloat(f128, temp_str)) |parsed_quad|
quad == parsed_quad
else |_|
false;
break :fmt_decimal if (could_roundtrip) try c.arena.dupe(u8, temp_str) else null;
}
// otherwise, fall back to the hexadecimal format
orelse try std.fmt.allocPrint(c.arena, "{x}", .{quad});
var node = try Tag.float_literal.create(c.arena, str);
if (is_negative) node = try Tag.negate.create(c.arena, node);
return maybeSuppressResult(c, used, node);
}
fn transBinaryConditionalOperator(c: *Context, scope: *Scope, stmt: *const clang.BinaryConditionalOperator, used: ResultUsed) TransError!Node {
// GNU extension of the ternary operator where the middle expression is
// omitted, the condition itself is returned if it evaluates to true
const qt = @as(*const clang.Expr, @ptrCast(stmt)).getType();
const res_is_bool = qualTypeIsBoolean(qt);
const casted_stmt = @as(*const clang.AbstractConditionalOperator, @ptrCast(stmt));
const cond_expr = casted_stmt.getCond();
const false_expr = casted_stmt.getFalseExpr();
// c: (cond_expr)?:(false_expr)
// zig: (blk: {
// const _cond_temp = (cond_expr);
// break :blk if (_cond_temp) _cond_temp else (false_expr);
// })
var block_scope = try Scope.Block.init(c, scope, true);
defer block_scope.deinit();
const cond_temp = try block_scope.reserveMangledName(c, "cond_temp");
const init_node = try transExpr(c, &block_scope.base, cond_expr, .used);
const ref_decl = try Tag.var_simple.create(c.arena, .{ .name = cond_temp, .init = init_node });
try block_scope.statements.append(ref_decl);
var cond_scope = Scope.Condition{
.base = .{
.parent = &block_scope.base,
.id = .condition,
},
};
defer cond_scope.deinit();
const cond_ident = try Tag.identifier.create(c.arena, cond_temp);
const ty = getExprQualType(c, cond_expr).getTypePtr();
const cond_node = try finishBoolExpr(c, &cond_scope.base, cond_expr.getBeginLoc(), ty, cond_ident, .used);
var then_body = cond_ident;
if (!res_is_bool and isBoolRes(init_node)) {
then_body = try Tag.int_from_bool.create(c.arena, then_body);
}
var else_body = try transExpr(c, &block_scope.base, false_expr, .used);
if (!res_is_bool and isBoolRes(else_body)) {
else_body = try Tag.int_from_bool.create(c.arena, else_body);
}
const if_node = try Tag.@"if".create(c.arena, .{
.cond = cond_node,
.then = then_body,
.@"else" = else_body,
});
const break_node = try Tag.break_val.create(c.arena, .{
.label = block_scope.label,
.val = if_node,
});
try block_scope.statements.append(break_node);
const res = try block_scope.complete(c);
return maybeSuppressResult(c, used, res);
}
fn transConditionalOperator(c: *Context, scope: *Scope, stmt: *const clang.ConditionalOperator, used: ResultUsed) TransError!Node {
var cond_scope = Scope.Condition{
.base = .{
.parent = scope,
.id = .condition,
},
};
defer cond_scope.deinit();
const qt = @as(*const clang.Expr, @ptrCast(stmt)).getType();
const res_is_bool = qualTypeIsBoolean(qt);
const casted_stmt = @as(*const clang.AbstractConditionalOperator, @ptrCast(stmt));
const cond_expr = casted_stmt.getCond();
const true_expr = casted_stmt.getTrueExpr();
const false_expr = casted_stmt.getFalseExpr();
const cond = try transBoolExpr(c, &cond_scope.base, cond_expr, .used);
var then_body = try transExpr(c, scope, true_expr, used);
if (!res_is_bool and isBoolRes(then_body)) {
then_body = try Tag.int_from_bool.create(c.arena, then_body);
}
var else_body = try transExpr(c, scope, false_expr, used);
if (!res_is_bool and isBoolRes(else_body)) {
else_body = try Tag.int_from_bool.create(c.arena, else_body);
}
const if_node = try Tag.@"if".create(c.arena, .{
.cond = cond,
.then = then_body,
.@"else" = else_body,
});
// Clang inserts ImplicitCast(ToVoid)'s to both rhs and lhs so we don't need to suppress the result here.
return if_node;
}
fn maybeSuppressResult(c: *Context, used: ResultUsed, result: Node) TransError!Node {
if (used == .used) return result;
return Tag.discard.create(c.arena, .{ .should_skip = false, .value = result });
}
fn addTopLevelDecl(c: *Context, name: []const u8, decl_node: Node) !void {
const gop = try c.global_scope.sym_table.getOrPut(name);
if (!gop.found_existing) {
gop.value_ptr.* = decl_node;
try c.global_scope.nodes.append(decl_node);
}
}
/// Add an "extern" function prototype declaration that's been declared within a scoped block.
/// Similar to static local variables, this will be wrapped in a struct to work with Zig's syntax requirements.
///
fn addLocalExternFnDecl(c: *Context, scope: *Scope, name: []const u8, decl_node: Node) !void {
const bs: *Scope.Block = try scope.findBlockScope(c);
// Special naming convention for local extern function wrapper struct,
// this named "ExternLocal_[name]".
const struct_name = try std.fmt.allocPrint(c.arena, "{s}_{s}", .{ Scope.Block.extern_inner_prepend, name });
// Outer Node for the wrapper struct
const node = try Tag.extern_local_fn.create(c.arena, .{ .name = struct_name, .init = decl_node });
try bs.statements.append(node);
try bs.discardVariable(c, struct_name);
}
fn transQualTypeInitializedStringLiteral(c: *Context, elem_ty: Node, string_lit: *const clang.StringLiteral) TypeError!Node {
const string_lit_size = string_lit.getLength();
const array_size = @as(usize, @intCast(string_lit_size));
// incomplete array initialized with empty string, will be translated as [1]T{0}
// see https://github.com/ziglang/zig/issues/8256
if (array_size == 0) return Tag.array_type.create(c.arena, .{ .len = 1, .elem_type = elem_ty });
return Tag.null_sentinel_array_type.create(c.arena, .{ .len = array_size, .elem_type = elem_ty });
}
/// Translate a qualtype for a variable with an initializer. This only matters
/// for incomplete arrays, since the initializer determines the size of the array.
fn transQualTypeInitialized(
c: *Context,
scope: *Scope,
qt: clang.QualType,
decl_init: *const clang.Expr,
source_loc: clang.SourceLocation,
) TypeError!Node {
const ty = qt.getTypePtr();
if (ty.getTypeClass() == .IncompleteArray) {
const incomplete_array_ty = @as(*const clang.IncompleteArrayType, @ptrCast(ty));
const elem_ty = try transType(c, scope, incomplete_array_ty.getElementType().getTypePtr(), source_loc);
switch (decl_init.getStmtClass()) {
.StringLiteralClass => {
const string_lit = @as(*const clang.StringLiteral, @ptrCast(decl_init));
return transQualTypeInitializedStringLiteral(c, elem_ty, string_lit);
},
.InitListExprClass => {
const init_expr = @as(*const clang.InitListExpr, @ptrCast(decl_init));
const size = init_expr.getNumInits();
if (init_expr.isStringLiteralInit()) {
assert(size == 1);
const string_lit = init_expr.getInit(0).castToStringLiteral().?;
return transQualTypeInitializedStringLiteral(c, elem_ty, string_lit);
}
return Tag.array_type.create(c.arena, .{ .len = size, .elem_type = elem_ty });
},
else => {},
}
}
return transQualType(c, scope, qt, source_loc);
}
fn transQualType(c: *Context, scope: *Scope, qt: clang.QualType, source_loc: clang.SourceLocation) TypeError!Node {
return transType(c, scope, qt.getTypePtr(), source_loc);
}
/// Produces a Zig AST node by translating a Clang QualType, respecting the width, but modifying the signed-ness.
/// Asserts the type is an integer.
fn transQualTypeIntWidthOf(c: *Context, ty: clang.QualType, is_signed: bool) TypeError!Node {
return transTypeIntWidthOf(c, qualTypeCanon(ty), is_signed);
}
/// Produces a Zig AST node by translating a Clang Type, respecting the width, but modifying the signed-ness.
/// Asserts the type is an integer.
fn transTypeIntWidthOf(c: *Context, ty: *const clang.Type, is_signed: bool) TypeError!Node {
assert(ty.getTypeClass() == .Builtin);
const builtin_ty = @as(*const clang.BuiltinType, @ptrCast(ty));
return Tag.type.create(c.arena, switch (builtin_ty.getKind()) {
.Char_U, .Char_S, .UChar, .SChar, .Char8 => if (is_signed) "i8" else "u8",
.UShort, .Short => if (is_signed) "c_short" else "c_ushort",
.UInt, .Int => if (is_signed) "c_int" else "c_uint",
.ULong, .Long => if (is_signed) "c_long" else "c_ulong",
.ULongLong, .LongLong => if (is_signed) "c_longlong" else "c_ulonglong",
.UInt128, .Int128 => if (is_signed) "i128" else "u128",
.Char16 => if (is_signed) "i16" else "u16",
.Char32 => if (is_signed) "i32" else "u32",
else => unreachable, // only call this function when it has already been determined the type is int
});
}
fn isCBuiltinType(qt: clang.QualType, kind: clang.BuiltinTypeKind) bool {
const c_type = qualTypeCanon(qt);
if (c_type.getTypeClass() != .Builtin)
return false;
const builtin_ty = @as(*const clang.BuiltinType, @ptrCast(c_type));
return builtin_ty.getKind() == kind;
}
fn qualTypeIsPtr(qt: clang.QualType) bool {
return qualTypeCanon(qt).getTypeClass() == .Pointer;
}
fn qualTypeIsBoolean(qt: clang.QualType) bool {
return qualTypeCanon(qt).isBooleanType();
}
fn qualTypeIntBitWidth(c: *Context, qt: clang.QualType) !u32 {
const ty = qt.getTypePtr();
switch (ty.getTypeClass()) {
.Builtin => {
const builtin_ty = @as(*const clang.BuiltinType, @ptrCast(ty));
switch (builtin_ty.getKind()) {
.Char_U,
.UChar,
.Char_S,
.SChar,
=> return 8,
.UInt128,
.Int128,
=> return 128,
else => return 0,
}
unreachable;
},
.Typedef => {
const typedef_ty = @as(*const clang.TypedefType, @ptrCast(ty));
const typedef_decl = typedef_ty.getDecl();
const type_name = try c.str(@as(*const clang.NamedDecl, @ptrCast(typedef_decl)).getName_bytes_begin());
if (mem.eql(u8, type_name, "uint8_t") or mem.eql(u8, type_name, "int8_t")) {
return 8;
} else if (mem.eql(u8, type_name, "uint16_t") or mem.eql(u8, type_name, "int16_t")) {
return 16;
} else if (mem.eql(u8, type_name, "uint32_t") or mem.eql(u8, type_name, "int32_t")) {
return 32;
} else if (mem.eql(u8, type_name, "uint64_t") or mem.eql(u8, type_name, "int64_t")) {
return 64;
} else {
return 0;
}
},
else => return 0,
}
}
fn qualTypeChildIsFnProto(qt: clang.QualType) bool {
const ty = qualTypeCanon(qt);
switch (ty.getTypeClass()) {
.FunctionProto, .FunctionNoProto => return true,
else => return false,
}
}
fn qualTypeCanon(qt: clang.QualType) *const clang.Type {
const canon = qt.getCanonicalType();
return canon.getTypePtr();
}
fn getExprQualType(c: *Context, expr: *const clang.Expr) clang.QualType {
blk: {
// If this is a C `char *`, turn it into a `const char *`
if (expr.getStmtClass() != .ImplicitCastExprClass) break :blk;
const cast_expr = @as(*const clang.ImplicitCastExpr, @ptrCast(expr));
if (cast_expr.getCastKind() != .ArrayToPointerDecay) break :blk;
const sub_expr = cast_expr.getSubExpr();
if (sub_expr.getStmtClass() != .StringLiteralClass) break :blk;
const array_qt = sub_expr.getType();
const array_type = @as(*const clang.ArrayType, @ptrCast(array_qt.getTypePtr()));
var pointee_qt = array_type.getElementType();
pointee_qt.addConst();
return c.clang_context.getPointerType(pointee_qt);
}
return expr.getType();
}
fn typeIsOpaque(c: *Context, ty: *const clang.Type, loc: clang.SourceLocation) bool {
switch (ty.getTypeClass()) {
.Builtin => {
const builtin_ty = @as(*const clang.BuiltinType, @ptrCast(ty));
return builtin_ty.getKind() == .Void;
},
.Record => {
const record_ty = @as(*const clang.RecordType, @ptrCast(ty));
const record_decl = record_ty.getDecl();
const record_def = record_decl.getDefinition() orelse
return true;
var it = record_def.field_begin();
const end_it = record_def.field_end();
while (it.neq(end_it)) : (it = it.next()) {
const field_decl = it.deref();
if (field_decl.isBitField()) {
return true;
}
}
return false;
},
.Elaborated => {
const elaborated_ty = @as(*const clang.ElaboratedType, @ptrCast(ty));
const qt = elaborated_ty.getNamedType();
return typeIsOpaque(c, qt.getTypePtr(), loc);
},
.Typedef => {
const typedef_ty = @as(*const clang.TypedefType, @ptrCast(ty));
const typedef_decl = typedef_ty.getDecl();
const underlying_type = typedef_decl.getUnderlyingType();
return typeIsOpaque(c, underlying_type.getTypePtr(), loc);
},
else => return false,
}
}
/// plain `char *` (not const; not explicitly signed or unsigned)
fn qualTypeIsCharStar(qt: clang.QualType) bool {
if (qualTypeIsPtr(qt)) {
const child_qt = qualTypeCanon(qt).getPointeeType();
return cIsUnqualifiedChar(child_qt) and !child_qt.isConstQualified();
}
return false;
}
/// C `char` without explicit signed or unsigned qualifier
fn cIsUnqualifiedChar(qt: clang.QualType) bool {
const c_type = qualTypeCanon(qt);
if (c_type.getTypeClass() != .Builtin) return false;
const builtin_ty = @as(*const clang.BuiltinType, @ptrCast(c_type));
return switch (builtin_ty.getKind()) {
.Char_S, .Char_U => true,
else => false,
};
}
fn cIsInteger(qt: clang.QualType) bool {
return cIsSignedInteger(qt) or cIsUnsignedInteger(qt);
}
fn cIsUnsignedInteger(qt: clang.QualType) bool {
const c_type = qualTypeCanon(qt);
if (c_type.getTypeClass() != .Builtin) return false;
const builtin_ty = @as(*const clang.BuiltinType, @ptrCast(c_type));
return switch (builtin_ty.getKind()) {
.Char_U,
.UChar,
.Char_S,
.UShort,
.UInt,
.ULong,
.ULongLong,
.UInt128,
.WChar_U,
=> true,
else => false,
};
}
fn cIntTypeToIndex(qt: clang.QualType) u8 {
const c_type = qualTypeCanon(qt);
assert(c_type.getTypeClass() == .Builtin);
const builtin_ty = @as(*const clang.BuiltinType, @ptrCast(c_type));
return switch (builtin_ty.getKind()) {
.Bool, .Char_U, .Char_S, .UChar, .SChar, .Char8 => 1,
.WChar_U, .WChar_S => 2,
.UShort, .Short, .Char16 => 3,
.UInt, .Int, .Char32 => 4,
.ULong, .Long => 5,
.ULongLong, .LongLong => 6,
.UInt128, .Int128 => 7,
else => unreachable,
};
}
fn cIntTypeCmp(a: clang.QualType, b: clang.QualType) math.Order {
const a_index = cIntTypeToIndex(a);
const b_index = cIntTypeToIndex(b);
return math.order(a_index, b_index);
}
/// Checks if expr is an integer literal >= 0
fn cIsNonNegativeIntLiteral(c: *Context, expr: *const clang.Expr) bool {
if (@as(*const clang.Stmt, @ptrCast(expr)).getStmtClass() == .IntegerLiteralClass) {
var signum: c_int = undefined;
if (!(@as(*const clang.IntegerLiteral, @ptrCast(expr)).getSignum(&signum, c.clang_context))) {
return false;
}
return signum >= 0;
}
return false;
}
fn cIsSignedInteger(qt: clang.QualType) bool {
const c_type = qualTypeCanon(qt);
if (c_type.getTypeClass() != .Builtin) return false;
const builtin_ty = @as(*const clang.BuiltinType, @ptrCast(c_type));
return switch (builtin_ty.getKind()) {
.SChar,
.Short,
.Int,
.Long,
.LongLong,
.Int128,
.WChar_S,
=> true,
else => false,
};
}
fn cIsNativeInt(qt: clang.QualType) bool {
const c_type = qualTypeCanon(qt);
if (c_type.getTypeClass() != .Builtin) return false;
const builtin_ty = @as(*const clang.BuiltinType, @ptrCast(c_type));
return builtin_ty.getKind() == .Int;
}
fn cIsFloating(qt: clang.QualType) bool {
const c_type = qualTypeCanon(qt);
if (c_type.getTypeClass() != .Builtin) return false;
const builtin_ty = @as(*const clang.BuiltinType, @ptrCast(c_type));
return switch (builtin_ty.getKind()) {
.Float,
.Double,
.Float128,
.LongDouble,
=> true,
else => false,
};
}
fn cIsLongLongInteger(qt: clang.QualType) bool {
const c_type = qualTypeCanon(qt);
if (c_type.getTypeClass() != .Builtin) return false;
const builtin_ty = @as(*const clang.BuiltinType, @ptrCast(c_type));
return switch (builtin_ty.getKind()) {
.LongLong, .ULongLong, .Int128, .UInt128 => true,
else => false,
};
}
fn transCreateNodeAssign(
c: *Context,
scope: *Scope,
result_used: ResultUsed,
lhs: *const clang.Expr,
rhs: *const clang.Expr,
) !Node {
// common case
// c: lhs = rhs
// zig: lhs = rhs
if (result_used == .unused) {
const lhs_node = try transExpr(c, scope, lhs, .used);
var rhs_node = try transExprCoercing(c, scope, rhs, .used);
if (!exprIsBooleanType(lhs) and isBoolRes(rhs_node)) {
rhs_node = try Tag.int_from_bool.create(c.arena, rhs_node);
}
return transCreateNodeInfixOp(c, .assign, lhs_node, rhs_node, .used);
}
// worst case
// c: lhs = rhs
// zig: (blk: {
// zig: const _tmp = rhs;
// zig: lhs = _tmp;
// zig: break :blk _tmp
// zig: })
var block_scope = try Scope.Block.init(c, scope, true);
defer block_scope.deinit();
const tmp = try block_scope.reserveMangledName(c, "tmp");
var rhs_node = try transExpr(c, &block_scope.base, rhs, .used);
if (!exprIsBooleanType(lhs) and isBoolRes(rhs_node)) {
rhs_node = try Tag.int_from_bool.create(c.arena, rhs_node);
}
const tmp_decl = try Tag.var_simple.create(c.arena, .{ .name = tmp, .init = rhs_node });
try block_scope.statements.append(tmp_decl);
const lhs_node = try transExpr(c, &block_scope.base, lhs, .used);
const tmp_ident = try Tag.identifier.create(c.arena, tmp);
const assign = try transCreateNodeInfixOp(c, .assign, lhs_node, tmp_ident, .used);
try block_scope.statements.append(assign);
const break_node = try Tag.break_val.create(c.arena, .{
.label = block_scope.label,
.val = tmp_ident,
});
try block_scope.statements.append(break_node);
return block_scope.complete(c);
}
fn transCreateNodeInfixOp(
c: *Context,
op: Tag,
lhs: Node,
rhs: Node,
used: ResultUsed,
) !Node {
const payload = try c.arena.create(ast.Payload.BinOp);
payload.* = .{
.base = .{ .tag = op },
.data = .{
.lhs = lhs,
.rhs = rhs,
},
};
return maybeSuppressResult(c, used, Node.initPayload(&payload.base));
}
fn transCreateNodeBoolInfixOp(
c: *Context,
scope: *Scope,
stmt: *const clang.BinaryOperator,
op: Tag,
used: ResultUsed,
) !Node {
std.debug.assert(op == .@"and" or op == .@"or");
const lhs = try transBoolExpr(c, scope, stmt.getLHS(), .used);
const rhs = try transBoolExpr(c, scope, stmt.getRHS(), .used);
return transCreateNodeInfixOp(c, op, lhs, rhs, used);
}
fn transCreateNodeAPInt(c: *Context, int: *const clang.APSInt) !Node {
const num_limbs = math.cast(usize, int.getNumWords()) orelse return error.OutOfMemory;
var aps_int = int;
const is_negative = int.isSigned() and int.isNegative();
if (is_negative) aps_int = aps_int.negate();
defer if (is_negative) {
aps_int.free();
};
const limbs = try c.arena.alloc(math.big.Limb, num_limbs);
defer c.arena.free(limbs);
const data = aps_int.getRawData();
switch (@sizeOf(math.big.Limb)) {
8 => {
var i: usize = 0;
while (i < num_limbs) : (i += 1) {
limbs[i] = data[i];
}
},
4 => {
var limb_i: usize = 0;
var data_i: usize = 0;
while (limb_i < num_limbs) : ({
limb_i += 2;
data_i += 1;
}) {
limbs[limb_i] = @as(u32, @truncate(data[data_i]));
limbs[limb_i + 1] = @as(u32, @truncate(data[data_i] >> 32));
}
},
else => @compileError("unimplemented"),
}
const big: math.big.int.Const = .{ .limbs = limbs, .positive = true };
const str = big.toStringAlloc(c.arena, 10, .lower) catch |err| switch (err) {
error.OutOfMemory => return error.OutOfMemory,
};
const res = try Tag.integer_literal.create(c.arena, str);
if (is_negative) return Tag.negate.create(c.arena, res);
return res;
}
fn transCreateNodeNumber(c: *Context, num: anytype, num_kind: enum { int, float }) !Node {
const fmt_s = switch (@typeInfo(@TypeOf(num))) {
.int, .comptime_int => "{d}",
else => "{s}",
};
const str = try std.fmt.allocPrint(c.arena, fmt_s, .{num});
if (num_kind == .float)
return Tag.float_literal.create(c.arena, str)
else
return Tag.integer_literal.create(c.arena, str);
}
fn transCreateNodeMacroFn(c: *Context, name: []const u8, ref: Node, proto_alias: *ast.Payload.Func) !Node {
var fn_params = std.array_list.Managed(ast.Payload.Param).init(c.gpa);
defer fn_params.deinit();
for (proto_alias.data.params) |param| {
const param_name = param.name orelse
try std.fmt.allocPrint(c.arena, "arg_{d}", .{c.getMangle()});
try fn_params.append(.{
.name = param_name,
.type = param.type,
.is_noalias = param.is_noalias,
});
}
const init = if (ref.castTag(.var_decl)) |v|
v.data.init.?
else if (ref.castTag(.var_simple) orelse ref.castTag(.pub_var_simple)) |v|
v.data.init
else
unreachable;
const unwrap_expr = try Tag.unwrap.create(c.arena, init);
const args = try c.arena.alloc(Node, fn_params.items.len);
for (fn_params.items, 0..) |param, i| {
args[i] = try Tag.identifier.create(c.arena, param.name.?);
}
const call_expr = try Tag.call.create(c.arena, .{
.lhs = unwrap_expr,
.args = args,
});
const return_expr = try Tag.@"return".create(c.arena, call_expr);
const block = try Tag.block_single.create(c.arena, return_expr);
return Tag.pub_inline_fn.create(c.arena, .{
.name = name,
.params = try c.arena.dupe(ast.Payload.Param, fn_params.items),
.return_type = proto_alias.data.return_type,
.body = block,
});
}
fn transCreateNodeShiftOp(
c: *Context,
scope: *Scope,
stmt: *const clang.BinaryOperator,
op: Tag,
used: ResultUsed,
) !Node {
std.debug.assert(op == .shl or op == .shr);
const lhs_expr = stmt.getLHS();
const rhs_expr = stmt.getRHS();
// lhs >> @as(u5, rh)
const lhs = try transExpr(c, scope, lhs_expr, .used);
const rhs = try transExprCoercing(c, scope, rhs_expr, .used);
const rhs_casted = try Tag.int_cast.create(c.arena, rhs);
return transCreateNodeInfixOp(c, op, lhs, rhs_casted, used);
}
fn transType(c: *Context, scope: *Scope, ty: *const clang.Type, source_loc: clang.SourceLocation) TypeError!Node {
switch (ty.getTypeClass()) {
.Builtin => {
const builtin_ty = @as(*const clang.BuiltinType, @ptrCast(ty));
return Tag.type.create(c.arena, switch (builtin_ty.getKind()) {
.Void => "anyopaque",
.Bool => "bool",
.Char_U, .UChar, .Char_S, .Char8 => "u8",
.SChar => "i8",
.UShort => "c_ushort",
.UInt => "c_uint",
.ULong => "c_ulong",
.ULongLong => "c_ulonglong",
.Short => "c_short",
.Int => "c_int",
.Long => "c_long",
.LongLong => "c_longlong",
.UInt128 => "u128",
.Int128 => "i128",
.Float => "f32",
.Double => "f64",
.Float128 => "f128",
.Float16 => "f16",
.LongDouble => "c_longdouble",
else => return fail(c, error.UnsupportedType, source_loc, "unsupported builtin type", .{}),
});
},
.FunctionProto => {
const fn_proto_ty = @as(*const clang.FunctionProtoType, @ptrCast(ty));
const fn_proto = try transFnProto(c, null, fn_proto_ty, source_loc, null, false);
return Node.initPayload(&fn_proto.base);
},
.FunctionNoProto => {
const fn_no_proto_ty = @as(*const clang.FunctionType, @ptrCast(ty));
const fn_proto = try transFnNoProto(c, fn_no_proto_ty, source_loc, null, false);
return Node.initPayload(&fn_proto.base);
},
.Paren => {
const paren_ty = @as(*const clang.ParenType, @ptrCast(ty));
return transQualType(c, scope, paren_ty.getInnerType(), source_loc);
},
.Pointer => {
const child_qt = ty.getPointeeType();
const is_fn_proto = qualTypeChildIsFnProto(child_qt);
const is_const = is_fn_proto or child_qt.isConstQualified();
const is_volatile = child_qt.isVolatileQualified();
const elem_type = try transQualType(c, scope, child_qt, source_loc);
const ptr_info: @FieldType(ast.Payload.Pointer, "data") = .{
.is_const = is_const,
.is_volatile = is_volatile,
.elem_type = elem_type,
};
if (is_fn_proto or
typeIsOpaque(c, child_qt.getTypePtr(), source_loc) or
qualTypeWasDemotedToOpaque(c, child_qt))
{
const ptr = try Tag.single_pointer.create(c.arena, ptr_info);
return Tag.optional_type.create(c.arena, ptr);
}
return Tag.c_pointer.create(c.arena, ptr_info);
},
.ConstantArray => {
const const_arr_ty = @as(*const clang.ConstantArrayType, @ptrCast(ty));
var size_ap_int: *const clang.APInt = undefined;
const_arr_ty.getSize(&size_ap_int);
defer size_ap_int.free();
const size = size_ap_int.getLimitedValue(usize);
const elem_type = try transType(c, scope, const_arr_ty.getElementType().getTypePtr(), source_loc);
return Tag.array_type.create(c.arena, .{ .len = size, .elem_type = elem_type });
},
.IncompleteArray => {
const incomplete_array_ty = @as(*const clang.IncompleteArrayType, @ptrCast(ty));
const child_qt = incomplete_array_ty.getElementType();
const is_const = child_qt.isConstQualified();
const is_volatile = child_qt.isVolatileQualified();
const elem_type = try transQualType(c, scope, child_qt, source_loc);
return Tag.c_pointer.create(c.arena, .{ .is_const = is_const, .is_volatile = is_volatile, .elem_type = elem_type });
},
.Typedef => {
const typedef_ty = @as(*const clang.TypedefType, @ptrCast(ty));
const typedef_decl = typedef_ty.getDecl();
var trans_scope = scope;
if (@as(*const clang.Decl, @ptrCast(typedef_decl)).castToNamedDecl()) |named_decl| {
const decl_name = try c.str(named_decl.getName_bytes_begin());
if (c.global_names.get(decl_name)) |_| trans_scope = &c.global_scope.base;
if (builtin_typedef_map.get(decl_name)) |builtin| return Tag.type.create(c.arena, builtin);
}
try transTypeDef(c, trans_scope, typedef_decl);
const name = c.decl_table.get(@intFromPtr(typedef_decl.getCanonicalDecl())).?;
return Tag.identifier.create(c.arena, name);
},
.Record => {
const record_ty = @as(*const clang.RecordType, @ptrCast(ty));
const record_decl = record_ty.getDecl();
var trans_scope = scope;
if (@as(*const clang.Decl, @ptrCast(record_decl)).castToNamedDecl()) |named_decl| {
const decl_name = try c.str(named_decl.getName_bytes_begin());
if (c.weak_global_names.contains(decl_name)) trans_scope = &c.global_scope.base;
}
try transRecordDecl(c, trans_scope, record_decl);
const name = c.decl_table.get(@intFromPtr(record_decl.getCanonicalDecl())).?;
return Tag.identifier.create(c.arena, name);
},
.Enum => {
const enum_ty = @as(*const clang.EnumType, @ptrCast(ty));
const enum_decl = enum_ty.getDecl();
var trans_scope = scope;
if (@as(*const clang.Decl, @ptrCast(enum_decl)).castToNamedDecl()) |named_decl| {
const decl_name = try c.str(named_decl.getName_bytes_begin());
if (c.weak_global_names.contains(decl_name)) trans_scope = &c.global_scope.base;
}
try transEnumDecl(c, trans_scope, enum_decl);
const name = c.decl_table.get(@intFromPtr(enum_decl.getCanonicalDecl())).?;
return Tag.identifier.create(c.arena, name);
},
.Elaborated => {
const elaborated_ty = @as(*const clang.ElaboratedType, @ptrCast(ty));
return transQualType(c, scope, elaborated_ty.getNamedType(), source_loc);
},
.Decayed => {
const decayed_ty = @as(*const clang.DecayedType, @ptrCast(ty));
return transQualType(c, scope, decayed_ty.getDecayedType(), source_loc);
},
.Attributed => {
const attributed_ty = @as(*const clang.AttributedType, @ptrCast(ty));
return transQualType(c, scope, attributed_ty.getEquivalentType(), source_loc);
},
.MacroQualified => {
const macroqualified_ty = @as(*const clang.MacroQualifiedType, @ptrCast(ty));
return transQualType(c, scope, macroqualified_ty.getModifiedType(), source_loc);
},
.TypeOf => {
const typeof_ty = @as(*const clang.TypeOfType, @ptrCast(ty));
return transQualType(c, scope, typeof_ty.getUnmodifiedType(), source_loc);
},
.TypeOfExpr => {
const typeofexpr_ty = @as(*const clang.TypeOfExprType, @ptrCast(ty));
const underlying_expr = transExpr(c, scope, typeofexpr_ty.getUnderlyingExpr(), .used) catch |err| switch (err) {
error.UnsupportedTranslation => {
return fail(c, error.UnsupportedType, source_loc, "unsupported underlying expression for TypeOfExpr", .{});
},
else => |e| return e,
};
return Tag.typeof.create(c.arena, underlying_expr);
},
.Vector => {
const vector_ty = @as(*const clang.VectorType, @ptrCast(ty));
const num_elements = vector_ty.getNumElements();
const element_qt = vector_ty.getElementType();
return Tag.vector.create(c.arena, .{
.lhs = try transCreateNodeNumber(c, num_elements, .int),
.rhs = try transQualType(c, scope, element_qt, source_loc),
});
},
.BitInt, .ExtVector => {
const type_name = try c.str(ty.getTypeClassName());
return fail(c, error.UnsupportedType, source_loc, "TODO implement translation of type: '{s}'", .{type_name});
},
else => {
const type_name = try c.str(ty.getTypeClassName());
return fail(c, error.UnsupportedType, source_loc, "unsupported type: '{s}'", .{type_name});
},
}
}
fn qualTypeWasDemotedToOpaque(c: *Context, qt: clang.QualType) bool {
const ty = qt.getTypePtr();
switch (qt.getTypeClass()) {
.Typedef => {
const typedef_ty = @as(*const clang.TypedefType, @ptrCast(ty));
const typedef_decl = typedef_ty.getDecl();
const underlying_type = typedef_decl.getUnderlyingType();
return qualTypeWasDemotedToOpaque(c, underlying_type);
},
.Record => {
const record_ty = @as(*const clang.RecordType, @ptrCast(ty));
const record_decl = record_ty.getDecl();
const canonical = @intFromPtr(record_decl.getCanonicalDecl());
if (c.opaque_demotes.contains(canonical)) return true;
// check all childern for opaque types.
var it = record_decl.field_begin();
const end_it = record_decl.field_end();
while (it.neq(end_it)) : (it = it.next()) {
const field_decl = it.deref();
if (qualTypeWasDemotedToOpaque(c, field_decl.getType())) return true;
}
return false;
},
.Enum => {
const enum_ty = @as(*const clang.EnumType, @ptrCast(ty));
const enum_decl = enum_ty.getDecl();
const canonical = @intFromPtr(enum_decl.getCanonicalDecl());
return c.opaque_demotes.contains(canonical);
},
.Elaborated => {
const elaborated_ty = @as(*const clang.ElaboratedType, @ptrCast(ty));
return qualTypeWasDemotedToOpaque(c, elaborated_ty.getNamedType());
},
.Decayed => {
const decayed_ty = @as(*const clang.DecayedType, @ptrCast(ty));
return qualTypeWasDemotedToOpaque(c, decayed_ty.getDecayedType());
},
.Attributed => {
const attributed_ty = @as(*const clang.AttributedType, @ptrCast(ty));
return qualTypeWasDemotedToOpaque(c, attributed_ty.getEquivalentType());
},
.MacroQualified => {
const macroqualified_ty = @as(*const clang.MacroQualifiedType, @ptrCast(ty));
return qualTypeWasDemotedToOpaque(c, macroqualified_ty.getModifiedType());
},
else => return false,
}
}
fn isAnyopaque(qt: clang.QualType) bool {
const ty = qt.getTypePtr();
switch (ty.getTypeClass()) {
.Builtin => {
const builtin_ty = @as(*const clang.BuiltinType, @ptrCast(ty));
return builtin_ty.getKind() == .Void;
},
.Typedef => {
const typedef_ty = @as(*const clang.TypedefType, @ptrCast(ty));
const typedef_decl = typedef_ty.getDecl();
return isAnyopaque(typedef_decl.getUnderlyingType());
},
.Elaborated => {
const elaborated_ty = @as(*const clang.ElaboratedType, @ptrCast(ty));
return isAnyopaque(elaborated_ty.getNamedType().getCanonicalType());
},
.Decayed => {
const decayed_ty = @as(*const clang.DecayedType, @ptrCast(ty));
return isAnyopaque(decayed_ty.getDecayedType().getCanonicalType());
},
.Attributed => {
const attributed_ty = @as(*const clang.AttributedType, @ptrCast(ty));
return isAnyopaque(attributed_ty.getEquivalentType().getCanonicalType());
},
.MacroQualified => {
const macroqualified_ty = @as(*const clang.MacroQualifiedType, @ptrCast(ty));
return isAnyopaque(macroqualified_ty.getModifiedType().getCanonicalType());
},
else => return false,
}
}
const FnDeclContext = struct {
fn_name: []const u8,
has_body: bool,
storage_class: clang.StorageClass,
is_always_inline: bool,
is_export: bool,
};
fn transCC(
c: *Context,
fn_ty: *const clang.FunctionType,
source_loc: clang.SourceLocation,
) !ast.Payload.Func.CallingConvention {
const clang_cc = fn_ty.getCallConv();
return switch (clang_cc) {
.C => .c,
.X86_64SysV => .x86_64_sysv,
.Win64 => .x86_64_win,
.X86StdCall => .x86_stdcall,
.X86FastCall => .x86_fastcall,
.X86ThisCall => .x86_thiscall,
.X86VectorCall => .x86_vectorcall,
.AArch64VectorCall => .aarch64_vfabi,
.AAPCS => .arm_aapcs,
.AAPCS_VFP => .arm_aapcs_vfp,
.M68kRTD => .m68k_rtd,
else => return fail(
c,
error.UnsupportedType,
source_loc,
"unsupported calling convention: {s}",
.{@tagName(clang_cc)},
),
};
}
fn transFnProto(
c: *Context,
fn_decl: ?*const clang.FunctionDecl,
fn_proto_ty: *const clang.FunctionProtoType,
source_loc: clang.SourceLocation,
fn_decl_context: ?FnDeclContext,
is_pub: bool,
) !*ast.Payload.Func {
const fn_ty = @as(*const clang.FunctionType, @ptrCast(fn_proto_ty));
const cc = try transCC(c, fn_ty, source_loc);
const is_var_args = fn_proto_ty.isVariadic();
return finishTransFnProto(c, fn_decl, fn_proto_ty, fn_ty, source_loc, fn_decl_context, is_var_args, cc, is_pub);
}
fn transFnNoProto(
c: *Context,
fn_ty: *const clang.FunctionType,
source_loc: clang.SourceLocation,
fn_decl_context: ?FnDeclContext,
is_pub: bool,
) !*ast.Payload.Func {
const cc = try transCC(c, fn_ty, source_loc);
const is_var_args = if (fn_decl_context) |ctx| (!ctx.is_export and ctx.storage_class != .Static and !ctx.is_always_inline) else true;
return finishTransFnProto(c, null, null, fn_ty, source_loc, fn_decl_context, is_var_args, cc, is_pub);
}
fn finishTransFnProto(
c: *Context,
fn_decl: ?*const clang.FunctionDecl,
fn_proto_ty: ?*const clang.FunctionProtoType,
fn_ty: *const clang.FunctionType,
source_loc: clang.SourceLocation,
fn_decl_context: ?FnDeclContext,
is_var_args: bool,
cc: ast.Payload.Func.CallingConvention,
is_pub: bool,
) !*ast.Payload.Func {
const is_export = if (fn_decl_context) |ctx| ctx.is_export else false;
const is_extern = if (fn_decl_context) |ctx| !ctx.has_body else false;
const is_inline = if (fn_decl_context) |ctx| ctx.is_always_inline else false;
const scope = &c.global_scope.base;
const param_count: usize = if (fn_proto_ty != null) fn_proto_ty.?.getNumParams() else 0;
var fn_params = try std.array_list.Managed(ast.Payload.Param).initCapacity(c.gpa, param_count);
defer fn_params.deinit();
var i: usize = 0;
while (i < param_count) : (i += 1) {
const param_qt = fn_proto_ty.?.getParamType(@as(c_uint, @intCast(i)));
const is_noalias = param_qt.isRestrictQualified();
const param_name: ?[]const u8 =
if (fn_decl) |decl| blk: {
const param = decl.getParamDecl(@as(c_uint, @intCast(i)));
const param_name: []const u8 = try c.str(@as(*const clang.NamedDecl, @ptrCast(param)).getName_bytes_begin());
if (param_name.len < 1)
break :blk null;
break :blk param_name;
} else null;
const type_node = try transQualType(c, scope, param_qt, source_loc);
fn_params.addOneAssumeCapacity().* = .{
.is_noalias = is_noalias,
.name = param_name,
.type = type_node,
};
}
const linksection_string = blk: {
if (fn_decl) |decl| {
var str_len: usize = undefined;
if (decl.getSectionAttribute(&str_len)) |str_ptr| {
break :blk str_ptr[0..str_len];
}
}
break :blk null;
};
const alignment = if (fn_decl) |decl| ClangAlignment.forFunc(c, decl).zigAlignment() else null;
const explicit_callconv = if ((is_inline or is_export or is_extern) and cc == .c) null else cc;
const return_type_node = blk: {
if (fn_ty.getNoReturnAttr()) {
break :blk Tag.noreturn_type.init();
} else {
const return_qt = fn_ty.getReturnType();
if (isAnyopaque(return_qt)) {
// convert primitive anyopaque to actual void (only for return type)
break :blk Tag.void_type.init();
} else {
break :blk transQualType(c, scope, return_qt, source_loc) catch |err| switch (err) {
error.UnsupportedType => {
try warn(c, scope, source_loc, "unsupported function proto return type", .{});
return err;
},
error.OutOfMemory => |e| return e,
};
}
}
};
const name: ?[]const u8 = if (fn_decl_context) |ctx| ctx.fn_name else null;
const payload = try c.arena.create(ast.Payload.Func);
payload.* = .{
.base = .{ .tag = .func },
.data = .{
.is_pub = is_pub,
.is_extern = is_extern,
.is_export = is_export,
.is_inline = is_inline,
.is_var_args = is_var_args,
.name = name,
.linksection_string = linksection_string,
.explicit_callconv = explicit_callconv,
.params = try c.arena.dupe(ast.Payload.Param, fn_params.items),
.return_type = return_type_node,
.body = null,
.alignment = alignment,
},
};
return payload;
}
fn warn(c: *Context, scope: *Scope, loc: clang.SourceLocation, comptime format: []const u8, args: anytype) !void {
const str = try c.locStr(loc);
const value = try std.fmt.allocPrint(c.arena, "// {s}: warning: " ++ format, .{str} ++ args);
try scope.appendNode(try Tag.warning.create(c.arena, value));
}
fn fail(
c: *Context,
err: anytype,
source_loc: clang.SourceLocation,
comptime format: []const u8,
args: anytype,
) (@TypeOf(err) || error{OutOfMemory}) {
try warn(c, &c.global_scope.base, source_loc, format, args);
return err;
}
pub fn failDecl(c: *Context, loc: clang.SourceLocation, name: []const u8, comptime format: []const u8, args: anytype) Error!void {
// location
// pub const name = @compileError(msg);
const fail_msg = try std.fmt.allocPrint(c.arena, format, args);
try addTopLevelDecl(c, name, try Tag.fail_decl.create(c.arena, .{ .actual = name, .mangled = fail_msg }));
const str = try c.locStr(loc);
const location_comment = try std.fmt.allocPrint(c.arena, "// {s}", .{str});
try c.global_scope.nodes.append(try Tag.warning.create(c.arena, location_comment));
}
const MacroCtx = struct {
source: []const u8,
list: []const CToken,
i: usize = 0,
loc: clang.SourceLocation,
name: []const u8,
refs_var_decl: bool = false,
fn_params: ?[]const ast.Payload.Param = null,
fn peek(self: *MacroCtx) ?CToken.Id {
if (self.i >= self.list.len) return null;
return self.list[self.i + 1].id;
}
fn next(self: *MacroCtx) ?CToken.Id {
if (self.i >= self.list.len) return null;
self.i += 1;
return self.list[self.i].id;
}
fn skip(self: *MacroCtx, c: *Context, expected_id: CToken.Id) ParseError!void {
const next_id = self.next().?;
if (next_id != expected_id and !(expected_id == .identifier and next_id == .extended_identifier)) {
try self.fail(
c,
"unable to translate C expr: expected '{s}' instead got '{s}'",
.{ expected_id.symbol(), next_id.symbol() },
);
return error.ParseError;
}
}
fn slice(self: *MacroCtx) []const u8 {
const tok = self.list[self.i];
return self.source[tok.start..tok.end];
}
fn fail(self: *MacroCtx, c: *Context, comptime fmt: []const u8, args: anytype) !void {
return failDecl(c, self.loc, self.name, fmt, args);
}
fn makeSlicer(self: *const MacroCtx) MacroSlicer {
return .{ .source = self.source, .tokens = self.list };
}
const MacroTranslateError = union(enum) {
undefined_identifier: []const u8,
invalid_arg_usage: []const u8,
};
fn checkTranslatableMacro(self: *MacroCtx, scope: *Scope, params: []const ast.Payload.Param) ?MacroTranslateError {
const slicer = self.makeSlicer();
var last_is_type_kw = false;
var i: usize = 1; // index 0 is the macro name
while (i < self.list.len) : (i += 1) {
const token = self.list[i];
switch (token.id) {
.period, .arrow => i += 1, // skip next token since field identifiers can be unknown
.keyword_struct, .keyword_union, .keyword_enum => if (!last_is_type_kw) {
last_is_type_kw = true;
continue;
},
.identifier, .extended_identifier => {
const identifier = slicer.slice(token);
const is_param = for (params) |param| {
if (param.name != null and mem.eql(u8, identifier, param.name.?)) break true;
} else false;
if (is_param and last_is_type_kw) {
return .{ .invalid_arg_usage = identifier };
}
if (!scope.contains(identifier) and !isBuiltinDefined(identifier) and !is_param) {
return .{ .undefined_identifier = identifier };
}
},
else => {},
}
last_is_type_kw = false;
}
return null;
}
fn checkFnParam(self: *MacroCtx, str: []const u8) bool {
if (self.fn_params == null) return false;
for (self.fn_params.?) |param| {
if (mem.eql(u8, param.name.?, str)) return true;
}
return false;
}
};
fn getMacroText(unit: *const clang.ASTUnit, c: *const Context, macro: *const clang.MacroDefinitionRecord) ![]const u8 {
const begin_loc = macro.getSourceRange_getBegin();
const end_loc = clang.Lexer.getLocForEndOfToken(macro.getSourceRange_getEnd(), c.source_manager, unit);
const begin_c = c.source_manager.getCharacterData(begin_loc);
const end_c = c.source_manager.getCharacterData(end_loc);
const slice_len = @intFromPtr(end_c) - @intFromPtr(begin_c);
var comp = aro.Compilation.init(c.gpa, std.fs.cwd());
defer comp.deinit();
const result = comp.addSourceFromBuffer("", begin_c[0..slice_len]) catch return error.OutOfMemory;
return c.arena.dupe(u8, result.buf);
}
fn transPreprocessorEntities(c: *Context, unit: *clang.ASTUnit) Error!void {
// TODO if we see #undef, delete it from the table
var it = unit.getLocalPreprocessingEntities_begin();
const it_end = unit.getLocalPreprocessingEntities_end();
var tok_list = std.array_list.Managed(CToken).init(c.gpa);
defer tok_list.deinit();
const scope = c.global_scope;
while (it.I != it_end.I) : (it.I += 1) {
const entity = it.deref();
tok_list.items.len = 0;
switch (entity.getKind()) {
.MacroDefinitionKind => {
const macro = @as(*clang.MacroDefinitionRecord, @ptrCast(entity));
const raw_name = macro.getName_getNameStart();
const begin_loc = macro.getSourceRange_getBegin();
const name = try c.str(raw_name);
if (scope.containsNow(name)) {
continue;
}
const source = try getMacroText(unit, c, macro);
try common.tokenizeMacro(source, &tok_list);
var macro_ctx = MacroCtx{
.source = source,
.list = tok_list.items,
.name = name,
.loc = begin_loc,
};
assert(mem.eql(u8, macro_ctx.slice(), name));
var macro_fn = false;
switch (macro_ctx.peek().?) {
.identifier, .extended_identifier => {
// if it equals itself, ignore. for example, from stdio.h:
// #define stdin stdin
const tok = macro_ctx.list[1];
if (mem.eql(u8, name, source[tok.start..tok.end])) {
assert(!c.global_names.contains(source[tok.start..tok.end]));
continue;
}
},
.nl, .eof => {
// this means it is a macro without a value
// We define it as an empty string so that it can still be used with ++
const str_node = try Tag.string_literal.create(c.arena, "\"\"");
const var_decl = try Tag.pub_var_simple.create(c.arena, .{ .name = name, .init = str_node });
try addTopLevelDecl(c, name, var_decl);
try c.global_scope.blank_macros.put(name, {});
continue;
},
.l_paren => {
// if the name is immediately followed by a '(' then it is a function
macro_fn = macro_ctx.list[0].end == macro_ctx.list[1].start;
},
else => {},
}
(if (macro_fn)
transMacroFnDefine(c, &macro_ctx)
else
transMacroDefine(c, &macro_ctx)) catch |err| switch (err) {
error.ParseError => continue,
error.OutOfMemory => |e| return e,
};
},
else => {},
}
}
}
fn transMacroDefine(c: *Context, m: *MacroCtx) ParseError!void {
const scope = &c.global_scope.base;
if (m.checkTranslatableMacro(scope, &.{})) |err| switch (err) {
.undefined_identifier => |ident| return m.fail(c, "unable to translate macro: undefined identifier `{s}`", .{ident}),
.invalid_arg_usage => unreachable, // no args
};
// Check if the macro only uses other blank macros.
while (true) {
switch (m.peek().?) {
.identifier, .extended_identifier => {
const tok = m.list[m.i + 1];
const slice = m.source[tok.start..tok.end];
if (c.global_scope.blank_macros.contains(slice)) {
m.i += 1;
continue;
}
},
.eof, .nl => {
try c.global_scope.blank_macros.put(m.name, {});
const init_node = try Tag.string_literal.create(c.arena, "\"\"");
const var_decl = try Tag.pub_var_simple.create(c.arena, .{ .name = m.name, .init = init_node });
try addTopLevelDecl(c, m.name, var_decl);
return;
},
else => {},
}
break;
}
const init_node = try parseCExpr(c, m, scope);
const last = m.next().?;
if (last != .eof and last != .nl)
return m.fail(c, "unable to translate C expr: unexpected token '{s}'", .{last.symbol()});
const node = node: {
const var_decl = try Tag.pub_var_simple.create(c.arena, .{ .name = m.name, .init = init_node });
if (getFnProto(c, var_decl)) |proto_node| {
// If a macro aliases a global variable which is a function pointer, we conclude that
// the macro is intended to represent a function that assumes the function pointer
// variable is non-null and calls it.
break :node try transCreateNodeMacroFn(c, m.name, var_decl, proto_node);
} else if (m.refs_var_decl) {
const return_type = try Tag.typeof.create(c.arena, init_node);
const return_expr = try Tag.@"return".create(c.arena, init_node);
const block = try Tag.block_single.create(c.arena, return_expr);
try warn(c, scope, m.loc, "macro '{s}' contains a runtime value, translated to function", .{m.name});
break :node try Tag.pub_inline_fn.create(c.arena, .{
.name = m.name,
.params = &.{},
.return_type = return_type,
.body = block,
});
}
break :node var_decl;
};
try addTopLevelDecl(c, m.name, node);
}
fn transMacroFnDefine(c: *Context, m: *MacroCtx) ParseError!void {
const macro_slicer = m.makeSlicer();
if (try c.pattern_list.match(c.gpa, macro_slicer)) |pattern| {
const decl = try Tag.pub_var_simple.create(c.arena, .{
.name = m.name,
.init = try Tag.helpers_macro.create(c.arena, pattern.impl),
});
try addTopLevelDecl(c, m.name, decl);
return;
}
var block_scope = try Scope.Block.init(c, &c.global_scope.base, false);
defer block_scope.deinit();
const scope = &block_scope.base;
try m.skip(c, .l_paren);
var fn_params = std.array_list.Managed(ast.Payload.Param).init(c.gpa);
defer fn_params.deinit();
while (true) {
if (!m.peek().?.isMacroIdentifier()) break;
_ = m.next();
const mangled_name = try block_scope.makeMangledName(c, m.slice());
try fn_params.append(.{
.is_noalias = false,
.name = mangled_name,
.type = Tag.@"anytype".init(),
});
try block_scope.discardVariable(c, mangled_name);
if (m.peek().? != .comma) break;
_ = m.next();
}
m.fn_params = fn_params.items;
try m.skip(c, .r_paren);
if (m.checkTranslatableMacro(scope, fn_params.items)) |err| switch (err) {
.undefined_identifier => |ident| return m.fail(c, "unable to translate macro: undefined identifier `{s}`", .{ident}),
.invalid_arg_usage => |ident| return m.fail(c, "unable to translate macro: untranslatable usage of arg `{s}`", .{ident}),
};
const expr = try parseCExpr(c, m, scope);
const last = m.next().?;
if (last != .eof and last != .nl)
return m.fail(c, "unable to translate C expr: unexpected token '{s}'", .{last.symbol()});
const typeof_arg = if (expr.castTag(.block)) |some| blk: {
const stmts = some.data.stmts;
const blk_last = stmts[stmts.len - 1];
const br = blk_last.castTag(.break_val).?;
break :blk br.data.val;
} else expr;
const return_type = if (typeof_arg.castTag(.helpers_cast) orelse typeof_arg.castTag(.std_mem_zeroinit)) |some|
some.data.lhs
else if (typeof_arg.castTag(.std_mem_zeroes)) |some|
some.data
else
try Tag.typeof.create(c.arena, typeof_arg);
const return_expr = try Tag.@"return".create(c.arena, expr);
try block_scope.statements.append(return_expr);
const fn_decl = try Tag.pub_inline_fn.create(c.arena, .{
.name = m.name,
.params = try c.arena.dupe(ast.Payload.Param, fn_params.items),
.return_type = return_type,
.body = try block_scope.complete(c),
});
try addTopLevelDecl(c, m.name, fn_decl);
}
const ParseError = Error || error{ParseError};
fn parseCExpr(c: *Context, m: *MacroCtx, scope: *Scope) ParseError!Node {
// TODO parseCAssignExpr here
var block_scope = try Scope.Block.init(c, scope, true);
defer block_scope.deinit();
const node = try parseCCondExpr(c, m, &block_scope.base);
if (m.next().? != .comma) {
m.i -= 1;
return node;
}
var last = node;
while (true) {
// suppress result
const ignore = try Tag.discard.create(c.arena, .{ .should_skip = false, .value = last });
try block_scope.statements.append(ignore);
last = try parseCCondExpr(c, m, &block_scope.base);
if (m.next().? != .comma) {
m.i -= 1;
break;
}
}
const break_node = try Tag.break_val.create(c.arena, .{
.label = block_scope.label,
.val = last,
});
try block_scope.statements.append(break_node);
return try block_scope.complete(c);
}
fn parseCNumLit(ctx: *Context, m: *MacroCtx) ParseError!Node {
const lit_bytes = m.slice();
var bytes = try std.ArrayListUnmanaged(u8).initCapacity(ctx.arena, lit_bytes.len + 3);
const prefix = aro.Tree.Token.NumberPrefix.fromString(lit_bytes);
switch (prefix) {
.binary => bytes.appendSliceAssumeCapacity("0b"),
.octal => bytes.appendSliceAssumeCapacity("0o"),
.hex => bytes.appendSliceAssumeCapacity("0x"),
.decimal => {},
}
const after_prefix = lit_bytes[prefix.stringLen()..];
const after_int = for (after_prefix, 0..) |c, i| switch (c) {
'.' => {
if (i == 0) {
bytes.appendAssumeCapacity('0');
}
break after_prefix[i..];
},
'e', 'E' => {
if (prefix != .hex) break after_prefix[i..];
bytes.appendAssumeCapacity(c);
},
'p', 'P' => break after_prefix[i..],
'0'...'9', 'a'...'d', 'A'...'D', 'f', 'F' => {
if (!prefix.digitAllowed(c)) break after_prefix[i..];
bytes.appendAssumeCapacity(c);
},
'\'' => {
bytes.appendAssumeCapacity('_');
},
else => break after_prefix[i..],
} else "";
const after_frac = frac: {
if (after_int.len == 0 or after_int[0] != '.') break :frac after_int;
bytes.appendAssumeCapacity('.');
for (after_int[1..], 1..) |c, i| {
if (c == '\'') {
bytes.appendAssumeCapacity('_');
continue;
}
if (!prefix.digitAllowed(c)) break :frac after_int[i..];
bytes.appendAssumeCapacity(c);
}
break :frac "";
};
const suffix_str = exponent: {
if (after_frac.len == 0) break :exponent after_frac;
switch (after_frac[0]) {
'e', 'E' => {},
'p', 'P' => if (prefix != .hex) break :exponent after_frac,
else => break :exponent after_frac,
}
bytes.appendAssumeCapacity(after_frac[0]);
for (after_frac[1..], 1..) |c, i| switch (c) {
'+', '-', '0'...'9' => {
bytes.appendAssumeCapacity(c);
},
'\'' => {
bytes.appendAssumeCapacity('_');
},
else => break :exponent after_frac[i..],
};
break :exponent "";
};
const is_float = after_int.len != suffix_str.len;
const suffix = aro.Tree.Token.NumberSuffix.fromString(suffix_str, if (is_float) .float else .int) orelse {
try m.fail(ctx, "invalid number suffix: '{s}'", .{suffix_str});
return error.ParseError;
};
if (suffix.isImaginary()) {
try m.fail(ctx, "TODO: imaginary literals", .{});
return error.ParseError;
}
if (suffix.isBitInt()) {
try m.fail(ctx, "TODO: _BitInt literals", .{});
return error.ParseError;
}
if (is_float) {
const type_node = try Tag.type.create(ctx.arena, switch (suffix) {
.F16 => "f16",
.F => "f32",
.None => "f64",
.L => "c_longdouble",
.W => "f80",
.Q, .F128 => "f128",
else => unreachable,
});
const rhs = try Tag.float_literal.create(ctx.arena, bytes.items);
return Tag.as.create(ctx.arena, .{ .lhs = type_node, .rhs = rhs });
} else {
const type_node = try Tag.type.create(ctx.arena, switch (suffix) {
.None => "c_int",
.U => "c_uint",
.L => "c_long",
.UL => "c_ulong",
.LL => "c_longlong",
.ULL => "c_ulonglong",
else => unreachable,
});
const value = std.fmt.parseInt(i128, bytes.items, 0) catch math.maxInt(i128);
// make the output less noisy by skipping promoteIntLiteral where
// it's guaranteed to not be required because of C standard type constraints
const guaranteed_to_fit = switch (suffix) {
.None => math.cast(i16, value) != null,
.U => math.cast(u16, value) != null,
.L => math.cast(i32, value) != null,
.UL => math.cast(u32, value) != null,
.LL => math.cast(i64, value) != null,
.ULL => math.cast(u64, value) != null,
else => unreachable,
};
const literal_node = try Tag.integer_literal.create(ctx.arena, bytes.items);
if (guaranteed_to_fit) {
return Tag.as.create(ctx.arena, .{ .lhs = type_node, .rhs = literal_node });
} else {
return Tag.helpers_promoteIntLiteral.create(ctx.arena, .{
.type = type_node,
.value = literal_node,
.base = try Tag.enum_literal.create(ctx.arena, @tagName(prefix)),
});
}
}
}
fn zigifyEscapeSequences(ctx: *Context, m: *MacroCtx) ![]const u8 {
var source = m.slice();
for (source, 0..) |c, i| {
if (c == '\"' or c == '\'') {
source = source[i..];
break;
}
}
for (source) |c| {
if (c == '\\' or c == '\t') {
break;
}
} else return source;
var bytes = try ctx.arena.alloc(u8, source.len * 2);
var state: enum {
start,
escape,
hex,
octal,
} = .start;
var i: usize = 0;
var count: u8 = 0;
var num: u8 = 0;
for (source) |c| {
switch (state) {
.escape => {
switch (c) {
'n', 'r', 't', '\\', '\'', '\"' => {
bytes[i] = c;
},
'0'...'7' => {
count += 1;
num += c - '0';
state = .octal;
bytes[i] = 'x';
},
'x' => {
state = .hex;
bytes[i] = 'x';
},
'a' => {
bytes[i] = 'x';
i += 1;
bytes[i] = '0';
i += 1;
bytes[i] = '7';
},
'b' => {
bytes[i] = 'x';
i += 1;
bytes[i] = '0';
i += 1;
bytes[i] = '8';
},
'f' => {
bytes[i] = 'x';
i += 1;
bytes[i] = '0';
i += 1;
bytes[i] = 'C';
},
'v' => {
bytes[i] = 'x';
i += 1;
bytes[i] = '0';
i += 1;
bytes[i] = 'B';
},
'?' => {
i -= 1;
bytes[i] = '?';
},
'u', 'U' => {
try m.fail(ctx, "macro tokenizing failed: TODO unicode escape sequences", .{});
return error.ParseError;
},
else => {
try m.fail(ctx, "macro tokenizing failed: unknown escape sequence", .{});
return error.ParseError;
},
}
i += 1;
if (state == .escape)
state = .start;
},
.start => {
if (c == '\t') {
bytes[i] = '\\';
i += 1;
bytes[i] = 't';
i += 1;
continue;
}
if (c == '\\') {
state = .escape;
}
bytes[i] = c;
i += 1;
},
.hex => {
switch (c) {
'0'...'9' => {
num = std.math.mul(u8, num, 16) catch {
try m.fail(ctx, "macro tokenizing failed: hex literal overflowed", .{});
return error.ParseError;
};
num += c - '0';
},
'a'...'f' => {
num = std.math.mul(u8, num, 16) catch {
try m.fail(ctx, "macro tokenizing failed: hex literal overflowed", .{});
return error.ParseError;
};
num += c - 'a' + 10;
},
'A'...'F' => {
num = std.math.mul(u8, num, 16) catch {
try m.fail(ctx, "macro tokenizing failed: hex literal overflowed", .{});
return error.ParseError;
};
num += c - 'A' + 10;
},
else => {
i += std.fmt.printInt(bytes[i..], num, 16, .lower, .{ .fill = '0', .width = 2 });
num = 0;
if (c == '\\')
state = .escape
else
state = .start;
bytes[i] = c;
i += 1;
},
}
},
.octal => {
const accept_digit = switch (c) {
// The maximum length of a octal literal is 3 digits
'0'...'7' => count < 3,
else => false,
};
if (accept_digit) {
count += 1;
num = std.math.mul(u8, num, 8) catch {
try m.fail(ctx, "macro tokenizing failed: octal literal overflowed", .{});
return error.ParseError;
};
num += c - '0';
} else {
i += std.fmt.printInt(bytes[i..], num, 16, .lower, .{ .fill = '0', .width = 2 });
num = 0;
count = 0;
if (c == '\\')
state = .escape
else
state = .start;
bytes[i] = c;
i += 1;
}
},
}
}
if (state == .hex or state == .octal)
i += std.fmt.printInt(bytes[i..], num, 16, .lower, .{ .fill = '0', .width = 2 });
return bytes[0..i];
}
/// non-ASCII characters (c > 127) are also treated as non-printable by ascii.hexEscape.
/// If a C string literal or char literal in a macro is not valid UTF-8, we need to escape
/// non-ASCII characters so that the Zig source we output will itself be UTF-8.
fn escapeUnprintables(ctx: *Context, m: *MacroCtx) ![]const u8 {
const zigified = try zigifyEscapeSequences(ctx, m);
if (std.unicode.utf8ValidateSlice(zigified)) return zigified;
const formatter = std.ascii.hexEscape(zigified, .lower);
const encoded_size: usize = @intCast(std.fmt.count("{f}", .{formatter}));
const output = try ctx.arena.alloc(u8, encoded_size);
return std.fmt.bufPrint(output, "{f}", .{formatter}) catch |err| switch (err) {
error.NoSpaceLeft => unreachable,
else => |e| return e,
};
}
fn parseCPrimaryExpr(c: *Context, m: *MacroCtx, scope: *Scope) ParseError!Node {
const tok = m.next().?;
const slice = m.slice();
switch (tok) {
.char_literal,
.char_literal_utf_8,
.char_literal_utf_16,
.char_literal_utf_32,
.char_literal_wide,
=> {
if (slice[0] != '\'' or slice[1] == '\\' or slice.len == 3) {
return Tag.char_literal.create(c.arena, try escapeUnprintables(c, m));
} else {
const str = try std.fmt.allocPrint(c.arena, "0x{x}", .{slice[1 .. slice.len - 1]});
return Tag.integer_literal.create(c.arena, str);
}
},
.string_literal,
.string_literal_utf_16,
.string_literal_utf_8,
.string_literal_utf_32,
.string_literal_wide,
=> {
return Tag.string_literal.create(c.arena, try escapeUnprintables(c, m));
},
.pp_num => {
return parseCNumLit(c, m);
},
.l_paren => {
const inner_node = try parseCExpr(c, m, scope);
try m.skip(c, .r_paren);
return inner_node;
},
else => {},
}
// The C preprocessor has no knowledge of C, so C keywords aren't special in macros.
// Thus the current token should be treated like an identifier if its name matches a parameter.
if (tok == .identifier or tok == .extended_identifier or m.checkFnParam(slice)) {
if (c.global_scope.blank_macros.contains(slice)) {
return parseCPrimaryExpr(c, m, scope);
}
const mangled_name = scope.getAlias(slice);
if (builtin_typedef_map.get(mangled_name)) |ty| return Tag.type.create(c.arena, ty);
const identifier = try Tag.identifier.create(c.arena, mangled_name);
scope.skipVariableDiscard(identifier.castTag(.identifier).?.data);
refs_var: {
const ident_node = c.global_scope.sym_table.get(slice) orelse break :refs_var;
const var_decl_node = ident_node.castTag(.var_decl) orelse break :refs_var;
if (!var_decl_node.data.is_const) m.refs_var_decl = true;
}
return identifier;
}
// for handling type macros (EVIL)
// TODO maybe detect and treat type macros as typedefs in parseCSpecifierQualifierList?
m.i -= 1;
if (try parseCTypeName(c, m, scope, true)) |type_name| {
return type_name;
}
try m.fail(c, "unable to translate C expr: unexpected token '{s}'", .{tok.symbol()});
return error.ParseError;
}
fn macroIntFromBool(c: *Context, node: Node) !Node {
if (!isBoolRes(node)) {
return node;
}
return Tag.int_from_bool.create(c.arena, node);
}
fn macroIntToBool(c: *Context, node: Node) !Node {
if (isBoolRes(node)) {
return node;
}
if (node.tag() == .string_literal) {
// @intFromPtr(node) != 0
const int_from_ptr = try Tag.int_from_ptr.create(c.arena, node);
return Tag.not_equal.create(c.arena, .{ .lhs = int_from_ptr, .rhs = Tag.zero_literal.init() });
}
// node != 0
return Tag.not_equal.create(c.arena, .{ .lhs = node, .rhs = Tag.zero_literal.init() });
}
fn parseCCondExpr(c: *Context, m: *MacroCtx, scope: *Scope) ParseError!Node {
const node = try parseCOrExpr(c, m, scope);
if (m.peek().? != .question_mark) {
return node;
}
_ = m.next();
const cond_body = try macroIntToBool(c, node);
const then_body = try parseCOrExpr(c, m, scope);
try m.skip(c, .colon);
const else_body = try parseCCondExpr(c, m, scope);
return Tag.@"if".create(c.arena, .{ .cond = cond_body, .then = then_body, .@"else" = else_body });
}
fn parseCOrExpr(c: *Context, m: *MacroCtx, scope: *Scope) ParseError!Node {
var node = try parseCAndExpr(c, m, scope);
while (m.next().? == .pipe_pipe) {
const lhs = try macroIntToBool(c, node);
const rhs = try macroIntToBool(c, try parseCAndExpr(c, m, scope));
node = try Tag.@"or".create(c.arena, .{ .lhs = lhs, .rhs = rhs });
}
m.i -= 1;
return node;
}
fn parseCAndExpr(c: *Context, m: *MacroCtx, scope: *Scope) ParseError!Node {
var node = try parseCBitOrExpr(c, m, scope);
while (m.next().? == .ampersand_ampersand) {
const lhs = try macroIntToBool(c, node);
const rhs = try macroIntToBool(c, try parseCBitOrExpr(c, m, scope));
node = try Tag.@"and".create(c.arena, .{ .lhs = lhs, .rhs = rhs });
}
m.i -= 1;
return node;
}
fn parseCBitOrExpr(c: *Context, m: *MacroCtx, scope: *Scope) ParseError!Node {
var node = try parseCBitXorExpr(c, m, scope);
while (m.next().? == .pipe) {
const lhs = try macroIntFromBool(c, node);
const rhs = try macroIntFromBool(c, try parseCBitXorExpr(c, m, scope));
node = try Tag.bit_or.create(c.arena, .{ .lhs = lhs, .rhs = rhs });
}
m.i -= 1;
return node;
}
fn parseCBitXorExpr(c: *Context, m: *MacroCtx, scope: *Scope) ParseError!Node {
var node = try parseCBitAndExpr(c, m, scope);
while (m.next().? == .caret) {
const lhs = try macroIntFromBool(c, node);
const rhs = try macroIntFromBool(c, try parseCBitAndExpr(c, m, scope));
node = try Tag.bit_xor.create(c.arena, .{ .lhs = lhs, .rhs = rhs });
}
m.i -= 1;
return node;
}
fn parseCBitAndExpr(c: *Context, m: *MacroCtx, scope: *Scope) ParseError!Node {
var node = try parseCEqExpr(c, m, scope);
while (m.next().? == .ampersand) {
const lhs = try macroIntFromBool(c, node);
const rhs = try macroIntFromBool(c, try parseCEqExpr(c, m, scope));
node = try Tag.bit_and.create(c.arena, .{ .lhs = lhs, .rhs = rhs });
}
m.i -= 1;
return node;
}
fn parseCEqExpr(c: *Context, m: *MacroCtx, scope: *Scope) ParseError!Node {
var node = try parseCRelExpr(c, m, scope);
while (true) {
switch (m.peek().?) {
.bang_equal => {
_ = m.next();
const lhs = try macroIntFromBool(c, node);
const rhs = try macroIntFromBool(c, try parseCRelExpr(c, m, scope));
node = try Tag.not_equal.create(c.arena, .{ .lhs = lhs, .rhs = rhs });
},
.equal_equal => {
_ = m.next();
const lhs = try macroIntFromBool(c, node);
const rhs = try macroIntFromBool(c, try parseCRelExpr(c, m, scope));
node = try Tag.equal.create(c.arena, .{ .lhs = lhs, .rhs = rhs });
},
else => return node,
}
}
}
fn parseCRelExpr(c: *Context, m: *MacroCtx, scope: *Scope) ParseError!Node {
var node = try parseCShiftExpr(c, m, scope);
while (true) {
switch (m.peek().?) {
.angle_bracket_right => {
_ = m.next();
const lhs = try macroIntFromBool(c, node);
const rhs = try macroIntFromBool(c, try parseCShiftExpr(c, m, scope));
node = try Tag.greater_than.create(c.arena, .{ .lhs = lhs, .rhs = rhs });
},
.angle_bracket_right_equal => {
_ = m.next();
const lhs = try macroIntFromBool(c, node);
const rhs = try macroIntFromBool(c, try parseCShiftExpr(c, m, scope));
node = try Tag.greater_than_equal.create(c.arena, .{ .lhs = lhs, .rhs = rhs });
},
.angle_bracket_left => {
_ = m.next();
const lhs = try macroIntFromBool(c, node);
const rhs = try macroIntFromBool(c, try parseCShiftExpr(c, m, scope));
node = try Tag.less_than.create(c.arena, .{ .lhs = lhs, .rhs = rhs });
},
.angle_bracket_left_equal => {
_ = m.next();
const lhs = try macroIntFromBool(c, node);
const rhs = try macroIntFromBool(c, try parseCShiftExpr(c, m, scope));
node = try Tag.less_than_equal.create(c.arena, .{ .lhs = lhs, .rhs = rhs });
},
else => return node,
}
}
}
fn parseCShiftExpr(c: *Context, m: *MacroCtx, scope: *Scope) ParseError!Node {
var node = try parseCAddSubExpr(c, m, scope);
while (true) {
switch (m.peek().?) {
.angle_bracket_angle_bracket_left => {
_ = m.next();
const lhs = try macroIntFromBool(c, node);
const rhs = try macroIntFromBool(c, try parseCAddSubExpr(c, m, scope));
node = try Tag.shl.create(c.arena, .{ .lhs = lhs, .rhs = rhs });
},
.angle_bracket_angle_bracket_right => {
_ = m.next();
const lhs = try macroIntFromBool(c, node);
const rhs = try macroIntFromBool(c, try parseCAddSubExpr(c, m, scope));
node = try Tag.shr.create(c.arena, .{ .lhs = lhs, .rhs = rhs });
},
else => return node,
}
}
}
fn parseCAddSubExpr(c: *Context, m: *MacroCtx, scope: *Scope) ParseError!Node {
var node = try parseCMulExpr(c, m, scope);
while (true) {
switch (m.peek().?) {
.plus => {
_ = m.next();
const lhs = try macroIntFromBool(c, node);
const rhs = try macroIntFromBool(c, try parseCMulExpr(c, m, scope));
node = try Tag.add.create(c.arena, .{ .lhs = lhs, .rhs = rhs });
},
.minus => {
_ = m.next();
const lhs = try macroIntFromBool(c, node);
const rhs = try macroIntFromBool(c, try parseCMulExpr(c, m, scope));
node = try Tag.sub.create(c.arena, .{ .lhs = lhs, .rhs = rhs });
},
else => return node,
}
}
}
fn parseCMulExpr(c: *Context, m: *MacroCtx, scope: *Scope) ParseError!Node {
var node = try parseCCastExpr(c, m, scope);
while (true) {
switch (m.next().?) {
.asterisk => {
const lhs = try macroIntFromBool(c, node);
const rhs = try macroIntFromBool(c, try parseCCastExpr(c, m, scope));
node = try Tag.mul.create(c.arena, .{ .lhs = lhs, .rhs = rhs });
},
.slash => {
const lhs = try macroIntFromBool(c, node);
const rhs = try macroIntFromBool(c, try parseCCastExpr(c, m, scope));
node = try Tag.macro_arithmetic.create(c.arena, .{ .op = .div, .lhs = lhs, .rhs = rhs });
},
.percent => {
const lhs = try macroIntFromBool(c, node);
const rhs = try macroIntFromBool(c, try parseCCastExpr(c, m, scope));
node = try Tag.macro_arithmetic.create(c.arena, .{ .op = .rem, .lhs = lhs, .rhs = rhs });
},
else => {
m.i -= 1;
return node;
},
}
}
}
fn parseCCastExpr(c: *Context, m: *MacroCtx, scope: *Scope) ParseError!Node {
switch (m.next().?) {
.l_paren => {
if (try parseCTypeName(c, m, scope, true)) |type_name| {
while (true) {
const next_token = m.next().?;
switch (next_token) {
.r_paren => break,
else => |next_tag| {
// Skip trailing blank defined before the RParen.
if ((next_tag == .identifier or next_tag == .extended_identifier) and
c.global_scope.blank_macros.contains(m.slice()))
continue;
try m.fail(
c,
"unable to translate C expr: expected ')' instead got '{s}'",
.{next_token.symbol()},
);
return error.ParseError;
},
}
}
if (m.peek().? == .l_brace) {
// initializer list
return parseCPostfixExpr(c, m, scope, type_name);
}
const node_to_cast = try parseCCastExpr(c, m, scope);
return Tag.helpers_cast.create(c.arena, .{ .lhs = type_name, .rhs = node_to_cast });
}
},
else => {},
}
m.i -= 1;
return parseCUnaryExpr(c, m, scope);
}
// allow_fail is set when unsure if we are parsing a type-name
fn parseCTypeName(c: *Context, m: *MacroCtx, scope: *Scope, allow_fail: bool) ParseError!?Node {
if (try parseCSpecifierQualifierList(c, m, scope, allow_fail)) |node| {
return try parseCAbstractDeclarator(c, m, node);
} else {
return null;
}
}
fn parseCSpecifierQualifierList(c: *Context, m: *MacroCtx, scope: *Scope, allow_fail: bool) ParseError!?Node {
const tok = m.next().?;
const slice = m.slice();
const mangled_name = scope.getAlias(slice);
if (!m.checkFnParam(mangled_name)) {
switch (tok) {
.identifier, .extended_identifier => {
if (c.global_scope.blank_macros.contains(m.slice())) {
return try parseCSpecifierQualifierList(c, m, scope, allow_fail);
}
if (!allow_fail or c.typedefs.contains(mangled_name)) {
if (builtin_typedef_map.get(mangled_name)) |ty| return try Tag.type.create(c.arena, ty);
return try Tag.identifier.create(c.arena, mangled_name);
}
},
.keyword_void => return try Tag.type.create(c.arena, "anyopaque"),
.keyword_bool => return try Tag.type.create(c.arena, "bool"),
.keyword_char,
.keyword_int,
.keyword_short,
.keyword_long,
.keyword_float,
.keyword_double,
.keyword_signed,
.keyword_unsigned,
.keyword_complex,
=> {
m.i -= 1;
return try parseCNumericType(c, m);
},
.keyword_enum, .keyword_struct, .keyword_union => {
// struct Foo will be declared as struct_Foo by transRecordDecl
try m.skip(c, .identifier);
const name = try std.fmt.allocPrint(c.arena, "{s}_{s}", .{ slice, m.slice() });
return try Tag.identifier.create(c.arena, name);
},
else => {},
}
} else {
if (allow_fail) {
m.i -= 1;
return null;
} else {
return try Tag.identifier.create(c.arena, mangled_name);
}
}
if (allow_fail) {
m.i -= 1;
return null;
} else {
try m.fail(c, "unable to translate C expr: unexpected token '{s}'", .{tok.symbol()});
return error.ParseError;
}
}
fn parseCNumericType(c: *Context, m: *MacroCtx) ParseError!Node {
const KwCounter = struct {
double: u8 = 0,
long: u8 = 0,
int: u8 = 0,
float: u8 = 0,
short: u8 = 0,
char: u8 = 0,
unsigned: u8 = 0,
signed: u8 = 0,
complex: u8 = 0,
fn eql(self: @This(), other: @This()) bool {
return meta.eql(self, other);
}
};
// Yes, these can be in *any* order
// This still doesn't cover cases where for example volatile is intermixed
var kw = KwCounter{};
// prevent overflow
var i: u8 = 0;
while (i < math.maxInt(u8)) : (i += 1) {
switch (m.next().?) {
.keyword_double => kw.double += 1,
.keyword_long => kw.long += 1,
.keyword_int => kw.int += 1,
.keyword_float => kw.float += 1,
.keyword_short => kw.short += 1,
.keyword_char => kw.char += 1,
.keyword_unsigned => kw.unsigned += 1,
.keyword_signed => kw.signed += 1,
.keyword_complex => kw.complex += 1,
else => {
m.i -= 1;
break;
},
}
}
if (kw.eql(.{ .int = 1 }) or kw.eql(.{ .signed = 1 }) or kw.eql(.{ .signed = 1, .int = 1 }))
return Tag.type.create(c.arena, "c_int");
if (kw.eql(.{ .unsigned = 1 }) or kw.eql(.{ .unsigned = 1, .int = 1 }))
return Tag.type.create(c.arena, "c_uint");
if (kw.eql(.{ .long = 1 }) or kw.eql(.{ .signed = 1, .long = 1 }) or kw.eql(.{ .long = 1, .int = 1 }) or kw.eql(.{ .signed = 1, .long = 1, .int = 1 }))
return Tag.type.create(c.arena, "c_long");
if (kw.eql(.{ .unsigned = 1, .long = 1 }) or kw.eql(.{ .unsigned = 1, .long = 1, .int = 1 }))
return Tag.type.create(c.arena, "c_ulong");
if (kw.eql(.{ .long = 2 }) or kw.eql(.{ .signed = 1, .long = 2 }) or kw.eql(.{ .long = 2, .int = 1 }) or kw.eql(.{ .signed = 1, .long = 2, .int = 1 }))
return Tag.type.create(c.arena, "c_longlong");
if (kw.eql(.{ .unsigned = 1, .long = 2 }) or kw.eql(.{ .unsigned = 1, .long = 2, .int = 1 }))
return Tag.type.create(c.arena, "c_ulonglong");
if (kw.eql(.{ .signed = 1, .char = 1 }))
return Tag.type.create(c.arena, "i8");
if (kw.eql(.{ .char = 1 }) or kw.eql(.{ .unsigned = 1, .char = 1 }))
return Tag.type.create(c.arena, "u8");
if (kw.eql(.{ .short = 1 }) or kw.eql(.{ .signed = 1, .short = 1 }) or kw.eql(.{ .short = 1, .int = 1 }) or kw.eql(.{ .signed = 1, .short = 1, .int = 1 }))
return Tag.type.create(c.arena, "c_short");
if (kw.eql(.{ .unsigned = 1, .short = 1 }) or kw.eql(.{ .unsigned = 1, .short = 1, .int = 1 }))
return Tag.type.create(c.arena, "c_ushort");
if (kw.eql(.{ .float = 1 }))
return Tag.type.create(c.arena, "f32");
if (kw.eql(.{ .double = 1 }))
return Tag.type.create(c.arena, "f64");
if (kw.eql(.{ .long = 1, .double = 1 })) {
try m.fail(c, "unable to translate: TODO long double", .{});
return error.ParseError;
}
if (kw.eql(.{ .float = 1, .complex = 1 })) {
try m.fail(c, "unable to translate: TODO _Complex", .{});
return error.ParseError;
}
if (kw.eql(.{ .double = 1, .complex = 1 })) {
try m.fail(c, "unable to translate: TODO _Complex", .{});
return error.ParseError;
}
if (kw.eql(.{ .long = 1, .double = 1, .complex = 1 })) {
try m.fail(c, "unable to translate: TODO _Complex", .{});
return error.ParseError;
}
try m.fail(c, "unable to translate: invalid numeric type", .{});
return error.ParseError;
}
fn parseCAbstractDeclarator(c: *Context, m: *MacroCtx, node: Node) ParseError!Node {
switch (m.next().?) {
.asterisk => {
// last token of `node`
const prev_id = m.list[m.i - 1].id;
if (prev_id == .keyword_void) {
const ptr = try Tag.single_pointer.create(c.arena, .{
.is_const = false,
.is_volatile = false,
.elem_type = node,
});
return Tag.optional_type.create(c.arena, ptr);
} else {
return Tag.c_pointer.create(c.arena, .{
.is_const = false,
.is_volatile = false,
.elem_type = node,
});
}
},
else => {
m.i -= 1;
return node;
},
}
}
fn parseCPostfixExpr(c: *Context, m: *MacroCtx, scope: *Scope, type_name: ?Node) ParseError!Node {
var node = try parseCPostfixExprInner(c, m, scope, type_name);
// In C the preprocessor would handle concatting strings while expanding macros.
// This should do approximately the same by concatting any strings and identifiers
// after a primary or postfix expression.
while (true) {
switch (m.peek().?) {
.string_literal,
.string_literal_utf_16,
.string_literal_utf_8,
.string_literal_utf_32,
.string_literal_wide,
=> {},
.identifier, .extended_identifier => {
const tok = m.list[m.i + 1];
const slice = m.source[tok.start..tok.end];
if (c.global_scope.blank_macros.contains(slice)) {
m.i += 1;
continue;
}
},
else => break,
}
const rhs = try parseCPostfixExprInner(c, m, scope, type_name);
node = try Tag.array_cat.create(c.arena, .{ .lhs = node, .rhs = rhs });
}
return node;
}
fn parseCPostfixExprInner(c: *Context, m: *MacroCtx, scope: *Scope, type_name: ?Node) ParseError!Node {
var node = type_name orelse try parseCPrimaryExpr(c, m, scope);
while (true) {
switch (m.next().?) {
.period => {
try m.skip(c, .identifier);
node = try Tag.field_access.create(c.arena, .{ .lhs = node, .field_name = m.slice() });
},
.arrow => {
try m.skip(c, .identifier);
const deref = try Tag.deref.create(c.arena, node);
node = try Tag.field_access.create(c.arena, .{ .lhs = deref, .field_name = m.slice() });
},
.l_bracket => {
const index_val = try macroIntFromBool(c, try parseCExpr(c, m, scope));
const index = try Tag.as.create(c.arena, .{
.lhs = try Tag.type.create(c.arena, "usize"),
.rhs = try Tag.int_cast.create(c.arena, index_val),
});
node = try Tag.array_access.create(c.arena, .{ .lhs = node, .rhs = index });
try m.skip(c, .r_bracket);
},
.l_paren => {
if (m.peek().? == .r_paren) {
m.i += 1;
node = try Tag.call.create(c.arena, .{ .lhs = node, .args = &[0]Node{} });
} else {
var args = std.array_list.Managed(Node).init(c.gpa);
defer args.deinit();
while (true) {
const arg = try parseCCondExpr(c, m, scope);
try args.append(arg);
const next_id = m.next().?;
switch (next_id) {
.comma => {},
.r_paren => break,
else => {
try m.fail(c, "unable to translate C expr: expected ',' or ')' instead got '{s}'", .{next_id.symbol()});
return error.ParseError;
},
}
}
node = try Tag.call.create(c.arena, .{ .lhs = node, .args = try c.arena.dupe(Node, args.items) });
}
},
.l_brace => {
// Check for designated field initializers
if (m.peek().? == .period) {
var init_vals = std.array_list.Managed(ast.Payload.ContainerInitDot.Initializer).init(c.gpa);
defer init_vals.deinit();
while (true) {
try m.skip(c, .period);
try m.skip(c, .identifier);
const name = m.slice();
try m.skip(c, .equal);
const val = try parseCCondExpr(c, m, scope);
try init_vals.append(.{ .name = name, .value = val });
const next_id = m.next().?;
switch (next_id) {
.comma => {},
.r_brace => break,
else => {
try m.fail(c, "unable to translate C expr: expected ',' or '}}' instead got '{s}'", .{next_id.symbol()});
return error.ParseError;
},
}
}
const tuple_node = try Tag.container_init_dot.create(c.arena, try c.arena.dupe(ast.Payload.ContainerInitDot.Initializer, init_vals.items));
node = try Tag.std_mem_zeroinit.create(c.arena, .{ .lhs = node, .rhs = tuple_node });
continue;
}
var init_vals = std.array_list.Managed(Node).init(c.gpa);
defer init_vals.deinit();
while (true) {
const val = try parseCCondExpr(c, m, scope);
try init_vals.append(val);
const next_id = m.next().?;
switch (next_id) {
.comma => {},
.r_brace => break,
else => {
try m.fail(c, "unable to translate C expr: expected ',' or '}}' instead got '{s}'", .{next_id.symbol()});
return error.ParseError;
},
}
}
const tuple_node = try Tag.tuple.create(c.arena, try c.arena.dupe(Node, init_vals.items));
node = try Tag.std_mem_zeroinit.create(c.arena, .{ .lhs = node, .rhs = tuple_node });
},
.plus_plus, .minus_minus => {
try m.fail(c, "TODO postfix inc/dec expr", .{});
return error.ParseError;
},
else => {
m.i -= 1;
return node;
},
}
}
}
fn parseCUnaryExpr(c: *Context, m: *MacroCtx, scope: *Scope) ParseError!Node {
sw: switch (m.next().?) {
.bang => {
const operand = try macroIntToBool(c, try parseCCastExpr(c, m, scope));
return Tag.not.create(c.arena, operand);
},
.minus => {
const operand = try macroIntFromBool(c, try parseCCastExpr(c, m, scope));
return Tag.negate.create(c.arena, operand);
},
.plus => return try parseCCastExpr(c, m, scope),
.tilde => {
const operand = try macroIntFromBool(c, try parseCCastExpr(c, m, scope));
return Tag.bit_not.create(c.arena, operand);
},
.asterisk => {
const operand = try parseCCastExpr(c, m, scope);
return Tag.deref.create(c.arena, operand);
},
.ampersand => {
const operand = try parseCCastExpr(c, m, scope);
return Tag.address_of.create(c.arena, operand);
},
.keyword_sizeof => {
// 'sizeof' could be used as a parameter to a macro function.
if (m.checkFnParam(m.slice())) break :sw;
const operand = if (m.peek().? == .l_paren) blk: {
_ = m.next();
const inner = (try parseCTypeName(c, m, scope, false)).?;
try m.skip(c, .r_paren);
break :blk inner;
} else try parseCUnaryExpr(c, m, scope);
return Tag.helpers_sizeof.create(c.arena, operand);
},
.keyword_alignof => {
// 'alignof' could be used as a parameter to a macro function.
if (m.checkFnParam(m.slice())) break :sw;
// TODO this won't work if using <stdalign.h>'s
// #define alignof _Alignof
try m.skip(c, .l_paren);
const operand = (try parseCTypeName(c, m, scope, false)).?;
try m.skip(c, .r_paren);
return Tag.alignof.create(c.arena, operand);
},
.plus_plus, .minus_minus => {
try m.fail(c, "TODO unary inc/dec expr", .{});
return error.ParseError;
},
else => {},
}
m.i -= 1;
return try parseCPostfixExpr(c, m, scope, null);
}
fn getContainer(c: *Context, node: Node) ?Node {
switch (node.tag()) {
.@"union",
.@"struct",
.address_of,
.bit_not,
.not,
.optional_type,
.negate,
.negate_wrap,
.array_type,
.c_pointer,
.single_pointer,
=> return node,
.identifier => {
const ident = node.castTag(.identifier).?;
if (c.global_scope.sym_table.get(ident.data)) |value| {
if (value.castTag(.var_decl)) |var_decl|
return getContainer(c, var_decl.data.init.?);
if (value.castTag(.var_simple) orelse value.castTag(.pub_var_simple)) |var_decl|
return getContainer(c, var_decl.data.init);
}
},
.field_access => {
const field_access = node.castTag(.field_access).?;
if (getContainerTypeOf(c, field_access.data.lhs)) |ty_node| {
if (ty_node.castTag(.@"struct") orelse ty_node.castTag(.@"union")) |container| {
for (container.data.fields) |field| {
if (mem.eql(u8, field.name, field_access.data.field_name)) {
return getContainer(c, field.type);
}
}
}
}
},
else => {},
}
return null;
}
fn getContainerTypeOf(c: *Context, ref: Node) ?Node {
if (ref.castTag(.identifier)) |ident| {
if (c.global_scope.sym_table.get(ident.data)) |value| {
if (value.castTag(.var_decl)) |var_decl| {
return getContainer(c, var_decl.data.type);
}
}
} else if (ref.castTag(.field_access)) |field_access| {
if (getContainerTypeOf(c, field_access.data.lhs)) |ty_node| {
if (ty_node.castTag(.@"struct") orelse ty_node.castTag(.@"union")) |container| {
for (container.data.fields) |field| {
if (mem.eql(u8, field.name, field_access.data.field_name)) {
return getContainer(c, field.type);
}
}
} else return ty_node;
}
}
return null;
}
fn getFnProto(c: *Context, ref: Node) ?*ast.Payload.Func {
const init = if (ref.castTag(.var_decl)) |v|
v.data.init orelse return null
else if (ref.castTag(.var_simple) orelse ref.castTag(.pub_var_simple)) |v|
v.data.init
else
return null;
if (getContainerTypeOf(c, init)) |ty_node| {
if (ty_node.castTag(.optional_type)) |prefix| {
if (prefix.data.castTag(.single_pointer)) |sp| {
if (sp.data.elem_type.castTag(.func)) |fn_proto| {
return fn_proto;
}
}
}
}
return null;
}