mirrors/zig
1
0
Fork 0
mirror of https://codeberg.org/ziglang/zig.git synced 2025-12-06 13:54:21 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 1
zig/lib/std/dwarf.zig
Andrew Kelley ceff278202 fixes to the previous commit 
* CompileStep: Avoid calling producesPdbFile() to determine whether the
   option should be respected. If the user asks for it, put it on the
   command line and let the Zig CLI deal with it appropriately.
 * Make the namespace of `std.dwarf.Format.dwarf32` no longer have a
   redundant "dwarf" in it.
 * Add `zig cc` integration for `-gdwarf32` and `-gdwarf64`.
 * Toss in a bonus bug fix for `-gdwarf-2`, `-gdwarf-3`, etc.
 * Avoid using default init values for struct fields unnecessarily.
 * Add missing cache hash addition for the new option.
2023-04-20 15:17:07 -07:00

1397 lines
54 KiB
Zig
Raw Blame History

const builtin = @import("builtin");
const std = @import("std.zig");
const debug = std.debug;
const fs = std.fs;
const io = std.io;
const mem = std.mem;
const math = std.math;
const leb = @import("leb128.zig");
pub const TAG = @import("dwarf/TAG.zig");
pub const AT = @import("dwarf/AT.zig");
pub const OP = @import("dwarf/OP.zig");
pub const LANG = @import("dwarf/LANG.zig");
pub const FORM = @import("dwarf/FORM.zig");
pub const ATE = @import("dwarf/ATE.zig");
pub const LLE = struct {
pub const end_of_list = 0x00;
pub const base_addressx = 0x01;
pub const startx_endx = 0x02;
pub const startx_length = 0x03;
pub const offset_pair = 0x04;
pub const default_location = 0x05;
pub const base_address = 0x06;
pub const start_end = 0x07;
pub const start_length = 0x08;
};
pub const CFA = struct {
pub const advance_loc = 0x40;
pub const offset = 0x80;
pub const restore = 0xc0;
pub const nop = 0x00;
pub const set_loc = 0x01;
pub const advance_loc1 = 0x02;
pub const advance_loc2 = 0x03;
pub const advance_loc4 = 0x04;
pub const offset_extended = 0x05;
pub const restore_extended = 0x06;
pub const @"undefined" = 0x07;
pub const same_value = 0x08;
pub const register = 0x09;
pub const remember_state = 0x0a;
pub const restore_state = 0x0b;
pub const def_cfa = 0x0c;
pub const def_cfa_register = 0x0d;
pub const def_cfa_offset = 0x0e;
// DWARF 3.
pub const def_cfa_expression = 0x0f;
pub const expression = 0x10;
pub const offset_extended_sf = 0x11;
pub const def_cfa_sf = 0x12;
pub const def_cfa_offset_sf = 0x13;
pub const val_offset = 0x14;
pub const val_offset_sf = 0x15;
pub const val_expression = 0x16;
pub const lo_user = 0x1c;
pub const hi_user = 0x3f;
// SGI/MIPS specific.
pub const MIPS_advance_loc8 = 0x1d;
// GNU extensions.
pub const GNU_window_save = 0x2d;
pub const GNU_args_size = 0x2e;
pub const GNU_negative_offset_extended = 0x2f;
};
pub const CHILDREN = struct {
pub const no = 0x00;
pub const yes = 0x01;
};
pub const LNS = struct {
pub const extended_op = 0x00;
pub const copy = 0x01;
pub const advance_pc = 0x02;
pub const advance_line = 0x03;
pub const set_file = 0x04;
pub const set_column = 0x05;
pub const negate_stmt = 0x06;
pub const set_basic_block = 0x07;
pub const const_add_pc = 0x08;
pub const fixed_advance_pc = 0x09;
pub const set_prologue_end = 0x0a;
pub const set_epilogue_begin = 0x0b;
pub const set_isa = 0x0c;
};
pub const LNE = struct {
pub const end_sequence = 0x01;
pub const set_address = 0x02;
pub const define_file = 0x03;
pub const set_discriminator = 0x04;
pub const lo_user = 0x80;
pub const hi_user = 0xff;
};
pub const UT = struct {
pub const compile = 0x01;
pub const @"type" = 0x02;
pub const partial = 0x03;
pub const skeleton = 0x04;
pub const split_compile = 0x05;
pub const split_type = 0x06;
pub const lo_user = 0x80;
pub const hi_user = 0xff;
};
pub const LNCT = struct {
pub const path = 0x1;
pub const directory_index = 0x2;
pub const timestamp = 0x3;
pub const size = 0x4;
pub const MD5 = 0x5;
pub const lo_user = 0x2000;
pub const hi_user = 0x3fff;
};
pub const RLE = struct {
pub const end_of_list = 0x00;
pub const base_addressx = 0x01;
pub const startx_endx = 0x02;
pub const startx_length = 0x03;
pub const offset_pair = 0x04;
pub const base_address = 0x05;
pub const start_end = 0x06;
pub const start_length = 0x07;
};
pub const CC = enum(u8) {
normal = 0x1,
program = 0x2,
nocall = 0x3,
pass_by_reference = 0x4,
pass_by_value = 0x5,
lo_user = 0x40,
hi_user = 0xff,
GNU_renesas_sh = 0x40,
GNU_borland_fastcall_i386 = 0x41,
};
pub const Format = enum { @"32", @"64" };
const PcRange = struct {
start: u64,
end: u64,
};
const Func = struct {
pc_range: ?PcRange,
name: ?[]const u8,
fn deinit(func: *Func, allocator: mem.Allocator) void {
if (func.name) |name| {
allocator.free(name);
}
}
};
const CompileUnit = struct {
version: u16,
is_64: bool,
die: *Die,
pc_range: ?PcRange,
str_offsets_base: usize,
addr_base: usize,
rnglists_base: usize,
loclists_base: usize,
};
const AbbrevTable = std.ArrayList(AbbrevTableEntry);
const AbbrevTableHeader = struct {
// offset from .debug_abbrev
offset: u64,
table: AbbrevTable,
fn deinit(header: *AbbrevTableHeader) void {
for (header.table.items) |*entry| {
entry.deinit();
}
header.table.deinit();
}
};
const AbbrevTableEntry = struct {
has_children: bool,
abbrev_code: u64,
tag_id: u64,
attrs: std.ArrayList(AbbrevAttr),
fn deinit(entry: *AbbrevTableEntry) void {
entry.attrs.deinit();
}
};
const AbbrevAttr = struct {
attr_id: u64,
form_id: u64,
/// Only valid if form_id is .implicit_const
payload: i64,
};
const FormValue = union(enum) {
Address: u64,
AddrOffset: usize,
Block: []u8,
Const: Constant,
ExprLoc: []u8,
Flag: bool,
SecOffset: u64,
Ref: u64,
RefAddr: u64,
String: []const u8,
StrPtr: u64,
StrOffset: usize,
LineStrPtr: u64,
LocListOffset: u64,
RangeListOffset: u64,
data16: [16]u8,
fn getString(fv: FormValue, di: DwarfInfo) ![]const u8 {
switch (fv) {
.String => |s| return s,
.StrPtr => |off| return di.getString(off),
.LineStrPtr => |off| return di.getLineString(off),
else => return badDwarf(),
}
}
fn getUInt(fv: FormValue, comptime U: type) !U {
switch (fv) {
.Const => |c| {
const int = try c.asUnsignedLe();
return math.cast(U, int) orelse return badDwarf();
},
.SecOffset => |x| return math.cast(U, x) orelse return badDwarf(),
else => return badDwarf(),
}
}
fn getData16(fv: FormValue) ![16]u8 {
switch (fv) {
.data16 => |d| return d,
else => return badDwarf(),
}
}
};
const Constant = struct {
payload: u64,
signed: bool,
fn asUnsignedLe(self: Constant) !u64 {
if (self.signed) return badDwarf();
return self.payload;
}
};
const Die = struct {
// Arena for Die's Attr's and FormValue's.
arena: std.heap.ArenaAllocator,
tag_id: u64,
has_children: bool,
attrs: std.ArrayListUnmanaged(Attr) = .{},
const Attr = struct {
id: u64,
value: FormValue,
};
fn deinit(self: *Die, allocator: mem.Allocator) void {
self.arena.deinit();
self.attrs.deinit(allocator);
}
fn getAttr(self: *const Die, id: u64) ?*const FormValue {
for (self.attrs.items) |*attr| {
if (attr.id == id) return &attr.value;
}
return null;
}
fn getAttrAddr(
self: *const Die,
di: *DwarfInfo,
id: u64,
compile_unit: CompileUnit,
) error{ InvalidDebugInfo, MissingDebugInfo }!u64 {
const form_value = self.getAttr(id) orelse return error.MissingDebugInfo;
return switch (form_value.*) {
FormValue.Address => |value| value,
FormValue.AddrOffset => |index| {
const debug_addr = di.debug_addr orelse return badDwarf();
// addr_base points to the first item after the header, however we
// need to read the header to know the size of each item. Empirically,
// it may disagree with is_64 on the compile unit.
// The header is 8 or 12 bytes depending on is_64.
if (compile_unit.addr_base < 8) return badDwarf();
const version = mem.readInt(u16, debug_addr[compile_unit.addr_base - 4 ..][0..2], di.endian);
if (version != 5) return badDwarf();
const addr_size = debug_addr[compile_unit.addr_base - 2];
const seg_size = debug_addr[compile_unit.addr_base - 1];
const byte_offset = compile_unit.addr_base + (addr_size + seg_size) * index;
if (byte_offset + addr_size > debug_addr.len) return badDwarf();
switch (addr_size) {
1 => return debug_addr[byte_offset],
2 => return mem.readInt(u16, debug_addr[byte_offset..][0..2], di.endian),
4 => return mem.readInt(u32, debug_addr[byte_offset..][0..4], di.endian),
8 => return mem.readInt(u64, debug_addr[byte_offset..][0..8], di.endian),
else => return badDwarf(),
}
},
else => error.InvalidDebugInfo,
};
}
fn getAttrSecOffset(self: *const Die, id: u64) !u64 {
const form_value = self.getAttr(id) orelse return error.MissingDebugInfo;
return form_value.getUInt(u64);
}
fn getAttrUnsignedLe(self: *const Die, id: u64) !u64 {
const form_value = self.getAttr(id) orelse return error.MissingDebugInfo;
return switch (form_value.*) {
FormValue.Const => |value| value.asUnsignedLe(),
else => error.InvalidDebugInfo,
};
}
fn getAttrRef(self: *const Die, id: u64) !u64 {
const form_value = self.getAttr(id) orelse return error.MissingDebugInfo;
return switch (form_value.*) {
FormValue.Ref => |value| value,
else => error.InvalidDebugInfo,
};
}
pub fn getAttrString(
self: *const Die,
di: *DwarfInfo,
id: u64,
opt_str: ?[]const u8,
compile_unit: CompileUnit,
) error{ InvalidDebugInfo, MissingDebugInfo }![]const u8 {
const form_value = self.getAttr(id) orelse return error.MissingDebugInfo;
switch (form_value.*) {
FormValue.String => |value| return value,
FormValue.StrPtr => |offset| return di.getString(offset),
FormValue.StrOffset => |index| {
const debug_str_offsets = di.debug_str_offsets orelse return badDwarf();
if (compile_unit.str_offsets_base == 0) return badDwarf();
if (compile_unit.is_64) {
const byte_offset = compile_unit.str_offsets_base + 8 * index;
if (byte_offset + 8 > debug_str_offsets.len) return badDwarf();
const offset = mem.readInt(u64, debug_str_offsets[byte_offset..][0..8], di.endian);
return getStringGeneric(opt_str, offset);
} else {
const byte_offset = compile_unit.str_offsets_base + 4 * index;
if (byte_offset + 4 > debug_str_offsets.len) return badDwarf();
const offset = mem.readInt(u32, debug_str_offsets[byte_offset..][0..4], di.endian);
return getStringGeneric(opt_str, offset);
}
},
FormValue.LineStrPtr => |offset| return di.getLineString(offset),
else => return badDwarf(),
}
}
};
const FileEntry = struct {
path: []const u8,
dir_index: u32 = 0,
mtime: u64 = 0,
size: u64 = 0,
md5: [16]u8 = [1]u8{0} ** 16,
};
const LineNumberProgram = struct {
address: u64,
file: usize,
line: i64,
column: u64,
version: u16,
is_stmt: bool,
basic_block: bool,
end_sequence: bool,
default_is_stmt: bool,
target_address: u64,
include_dirs: []const FileEntry,
prev_valid: bool,
prev_address: u64,
prev_file: usize,
prev_line: i64,
prev_column: u64,
prev_is_stmt: bool,
prev_basic_block: bool,
prev_end_sequence: bool,
// Reset the state machine following the DWARF specification
pub fn reset(self: *LineNumberProgram) void {
self.address = 0;
self.file = 1;
self.line = 1;
self.column = 0;
self.is_stmt = self.default_is_stmt;
self.basic_block = false;
self.end_sequence = false;
// Invalidate all the remaining fields
self.prev_valid = false;
self.prev_address = 0;
self.prev_file = undefined;
self.prev_line = undefined;
self.prev_column = undefined;
self.prev_is_stmt = undefined;
self.prev_basic_block = undefined;
self.prev_end_sequence = undefined;
}
pub fn init(
is_stmt: bool,
include_dirs: []const FileEntry,
target_address: u64,
version: u16,
) LineNumberProgram {
return LineNumberProgram{
.address = 0,
.file = 1,
.line = 1,
.column = 0,
.version = version,
.is_stmt = is_stmt,
.basic_block = false,
.end_sequence = false,
.include_dirs = include_dirs,
.default_is_stmt = is_stmt,
.target_address = target_address,
.prev_valid = false,
.prev_address = 0,
.prev_file = undefined,
.prev_line = undefined,
.prev_column = undefined,
.prev_is_stmt = undefined,
.prev_basic_block = undefined,
.prev_end_sequence = undefined,
};
}
pub fn checkLineMatch(
self: *LineNumberProgram,
allocator: mem.Allocator,
file_entries: []const FileEntry,
) !?debug.LineInfo {
if (self.prev_valid and
self.target_address >= self.prev_address and
self.target_address < self.address)
{
const file_index = if (self.version >= 5) self.prev_file else i: {
if (self.prev_file == 0) return missingDwarf();
break :i self.prev_file - 1;
};
if (file_index >= file_entries.len) return badDwarf();
const file_entry = &file_entries[file_index];
if (file_entry.dir_index >= self.include_dirs.len) return badDwarf();
const dir_name = self.include_dirs[file_entry.dir_index].path;
const file_name = try fs.path.join(allocator, &[_][]const u8{
dir_name, file_entry.path,
});
return debug.LineInfo{
.line = if (self.prev_line >= 0) @intCast(u64, self.prev_line) else 0,
.column = self.prev_column,
.file_name = file_name,
};
}
self.prev_valid = true;
self.prev_address = self.address;
self.prev_file = self.file;
self.prev_line = self.line;
self.prev_column = self.column;
self.prev_is_stmt = self.is_stmt;
self.prev_basic_block = self.basic_block;
self.prev_end_sequence = self.end_sequence;
return null;
}
};
fn readUnitLength(in_stream: anytype, endian: std.builtin.Endian, is_64: *bool) !u64 {
const first_32_bits = try in_stream.readInt(u32, endian);
is_64.* = (first_32_bits == 0xffffffff);
if (is_64.*) {
return in_stream.readInt(u64, endian);
} else {
if (first_32_bits >= 0xfffffff0) return badDwarf();
// TODO this cast should not be needed
return @as(u64, first_32_bits);
}
}
// TODO the nosuspends here are workarounds
fn readAllocBytes(allocator: mem.Allocator, in_stream: anytype, size: usize) ![]u8 {
const buf = try allocator.alloc(u8, size);
errdefer allocator.free(buf);
if ((try nosuspend in_stream.read(buf)) < size) return error.EndOfFile;
return buf;
}
// TODO the nosuspends here are workarounds
fn readAddress(in_stream: anytype, endian: std.builtin.Endian, is_64: bool) !u64 {
return nosuspend if (is_64)
try in_stream.readInt(u64, endian)
else
@as(u64, try in_stream.readInt(u32, endian));
}
fn parseFormValueBlockLen(allocator: mem.Allocator, in_stream: anytype, size: usize) !FormValue {
const buf = try readAllocBytes(allocator, in_stream, size);
return FormValue{ .Block = buf };
}
// TODO the nosuspends here are workarounds
fn parseFormValueBlock(allocator: mem.Allocator, in_stream: anytype, endian: std.builtin.Endian, size: usize) !FormValue {
const block_len = try nosuspend in_stream.readVarInt(usize, endian, size);
return parseFormValueBlockLen(allocator, in_stream, block_len);
}
fn parseFormValueConstant(in_stream: anytype, signed: bool, endian: std.builtin.Endian, comptime size: i32) !FormValue {
// TODO: Please forgive me, I've worked around zig not properly spilling some intermediate values here.
// `nosuspend` should be removed from all the function calls once it is fixed.
return FormValue{
.Const = Constant{
.signed = signed,
.payload = switch (size) {
1 => try nosuspend in_stream.readInt(u8, endian),
2 => try nosuspend in_stream.readInt(u16, endian),
4 => try nosuspend in_stream.readInt(u32, endian),
8 => try nosuspend in_stream.readInt(u64, endian),
-1 => blk: {
if (signed) {
const x = try nosuspend leb.readILEB128(i64, in_stream);
break :blk @bitCast(u64, x);
} else {
const x = try nosuspend leb.readULEB128(u64, in_stream);
break :blk x;
}
},
else => @compileError("Invalid size"),
},
},
};
}
// TODO the nosuspends here are workarounds
fn parseFormValueRef(in_stream: anytype, endian: std.builtin.Endian, size: i32) !FormValue {
return FormValue{
.Ref = switch (size) {
1 => try nosuspend in_stream.readInt(u8, endian),
2 => try nosuspend in_stream.readInt(u16, endian),
4 => try nosuspend in_stream.readInt(u32, endian),
8 => try nosuspend in_stream.readInt(u64, endian),
-1 => try nosuspend leb.readULEB128(u64, in_stream),
else => unreachable,
},
};
}
// TODO the nosuspends here are workarounds
fn parseFormValue(allocator: mem.Allocator, in_stream: anytype, form_id: u64, endian: std.builtin.Endian, is_64: bool) anyerror!FormValue {
return switch (form_id) {
FORM.addr => FormValue{ .Address = try readAddress(in_stream, endian, @sizeOf(usize) == 8) },
FORM.addrx1 => return FormValue{ .AddrOffset = try in_stream.readInt(u8, endian) },
FORM.addrx2 => return FormValue{ .AddrOffset = try in_stream.readInt(u16, endian) },
FORM.addrx3 => return FormValue{ .AddrOffset = try in_stream.readInt(u24, endian) },
FORM.addrx4 => return FormValue{ .AddrOffset = try in_stream.readInt(u32, endian) },
FORM.addrx => return FormValue{ .AddrOffset = try nosuspend leb.readULEB128(usize, in_stream) },
FORM.block1 => parseFormValueBlock(allocator, in_stream, endian, 1),
FORM.block2 => parseFormValueBlock(allocator, in_stream, endian, 2),
FORM.block4 => parseFormValueBlock(allocator, in_stream, endian, 4),
FORM.block => {
const block_len = try nosuspend leb.readULEB128(usize, in_stream);
return parseFormValueBlockLen(allocator, in_stream, block_len);
},
FORM.data1 => parseFormValueConstant(in_stream, false, endian, 1),
FORM.data2 => parseFormValueConstant(in_stream, false, endian, 2),
FORM.data4 => parseFormValueConstant(in_stream, false, endian, 4),
FORM.data8 => parseFormValueConstant(in_stream, false, endian, 8),
FORM.data16 => {
var buf: [16]u8 = undefined;
if ((try nosuspend in_stream.readAll(&buf)) < 16) return error.EndOfFile;
return FormValue{ .data16 = buf };
},
FORM.udata, FORM.sdata => {
const signed = form_id == FORM.sdata;
return parseFormValueConstant(in_stream, signed, endian, -1);
},
FORM.exprloc => {
const size = try nosuspend leb.readULEB128(usize, in_stream);
const buf = try readAllocBytes(allocator, in_stream, size);
return FormValue{ .ExprLoc = buf };
},
FORM.flag => FormValue{ .Flag = (try nosuspend in_stream.readByte()) != 0 },
FORM.flag_present => FormValue{ .Flag = true },
FORM.sec_offset => FormValue{ .SecOffset = try readAddress(in_stream, endian, is_64) },
FORM.ref1 => parseFormValueRef(in_stream, endian, 1),
FORM.ref2 => parseFormValueRef(in_stream, endian, 2),
FORM.ref4 => parseFormValueRef(in_stream, endian, 4),
FORM.ref8 => parseFormValueRef(in_stream, endian, 8),
FORM.ref_udata => parseFormValueRef(in_stream, endian, -1),
FORM.ref_addr => FormValue{ .RefAddr = try readAddress(in_stream, endian, is_64) },
FORM.ref_sig8 => FormValue{ .Ref = try nosuspend in_stream.readInt(u64, endian) },
FORM.string => FormValue{ .String = try in_stream.readUntilDelimiterAlloc(allocator, 0, math.maxInt(usize)) },
FORM.strp => FormValue{ .StrPtr = try readAddress(in_stream, endian, is_64) },
FORM.strx1 => return FormValue{ .StrOffset = try in_stream.readInt(u8, endian) },
FORM.strx2 => return FormValue{ .StrOffset = try in_stream.readInt(u16, endian) },
FORM.strx3 => return FormValue{ .StrOffset = try in_stream.readInt(u24, endian) },
FORM.strx4 => return FormValue{ .StrOffset = try in_stream.readInt(u32, endian) },
FORM.strx => return FormValue{ .StrOffset = try nosuspend leb.readULEB128(usize, in_stream) },
FORM.line_strp => FormValue{ .LineStrPtr = try readAddress(in_stream, endian, is_64) },
FORM.indirect => {
const child_form_id = try nosuspend leb.readULEB128(u64, in_stream);
if (true) {
return parseFormValue(allocator, in_stream, child_form_id, endian, is_64);
}
const F = @TypeOf(async parseFormValue(allocator, in_stream, child_form_id, endian, is_64));
var frame = try allocator.create(F);
defer allocator.destroy(frame);
return await @asyncCall(frame, {}, parseFormValue, .{ allocator, in_stream, child_form_id, endian, is_64 });
},
FORM.implicit_const => FormValue{ .Const = Constant{ .signed = true, .payload = undefined } },
FORM.loclistx => return FormValue{ .LocListOffset = try nosuspend leb.readULEB128(u64, in_stream) },
FORM.rnglistx => return FormValue{ .RangeListOffset = try nosuspend leb.readULEB128(u64, in_stream) },
else => {
//std.debug.print("unrecognized form id: {x}\n", .{form_id});
return badDwarf();
},
};
}
fn getAbbrevTableEntry(abbrev_table: *const AbbrevTable, abbrev_code: u64) ?*const AbbrevTableEntry {
for (abbrev_table.items) |*table_entry| {
if (table_entry.abbrev_code == abbrev_code) return table_entry;
}
return null;
}
pub const DwarfInfo = struct {
endian: std.builtin.Endian,
// No memory is owned by the DwarfInfo
debug_info: []const u8,
debug_abbrev: []const u8,
debug_str: []const u8,
debug_str_offsets: ?[]const u8,
debug_line: []const u8,
debug_line_str: ?[]const u8,
debug_ranges: ?[]const u8,
debug_loclists: ?[]const u8,
debug_rnglists: ?[]const u8,
debug_addr: ?[]const u8,
debug_names: ?[]const u8,
debug_frame: ?[]const u8,
// Filled later by the initializer
abbrev_table_list: std.ArrayListUnmanaged(AbbrevTableHeader) = .{},
compile_unit_list: std.ArrayListUnmanaged(CompileUnit) = .{},
func_list: std.ArrayListUnmanaged(Func) = .{},
pub fn deinit(di: *DwarfInfo, allocator: mem.Allocator) void {
for (di.abbrev_table_list.items) |*abbrev| {
abbrev.deinit();
}
di.abbrev_table_list.deinit(allocator);
for (di.compile_unit_list.items) |*cu| {
cu.die.deinit(allocator);
allocator.destroy(cu.die);
}
di.compile_unit_list.deinit(allocator);
for (di.func_list.items) |*func| {
func.deinit(allocator);
}
di.func_list.deinit(allocator);
}
pub fn getSymbolName(di: *DwarfInfo, address: u64) ?[]const u8 {
for (di.func_list.items) |*func| {
if (func.pc_range) |range| {
if (address >= range.start and address < range.end) {
return func.name;
}
}
}
return null;
}
fn scanAllFunctions(di: *DwarfInfo, allocator: mem.Allocator) !void {
var stream = io.fixedBufferStream(di.debug_info);
const in = stream.reader();
const seekable = &stream.seekableStream();
var this_unit_offset: u64 = 0;
var tmp_arena = std.heap.ArenaAllocator.init(allocator);
defer tmp_arena.deinit();
const arena = tmp_arena.allocator();
while (this_unit_offset < try seekable.getEndPos()) {
try seekable.seekTo(this_unit_offset);
var is_64: bool = undefined;
const unit_length = try readUnitLength(in, di.endian, &is_64);
if (unit_length == 0) return;
const next_offset = unit_length + (if (is_64) @as(usize, 12) else @as(usize, 4));
const version = try in.readInt(u16, di.endian);
if (version < 2 or version > 5) return badDwarf();
var address_size: u8 = undefined;
var debug_abbrev_offset: u64 = undefined;
if (version >= 5) {
const unit_type = try in.readInt(u8, di.endian);
if (unit_type != UT.compile) return badDwarf();
address_size = try in.readByte();
debug_abbrev_offset = if (is_64)
try in.readInt(u64, di.endian)
else
try in.readInt(u32, di.endian);
} else {
debug_abbrev_offset = if (is_64)
try in.readInt(u64, di.endian)
else
try in.readInt(u32, di.endian);
address_size = try in.readByte();
}
if (address_size != @sizeOf(usize)) return badDwarf();
const compile_unit_pos = try seekable.getPos();
const abbrev_table = try di.getAbbrevTable(allocator, debug_abbrev_offset);
try seekable.seekTo(compile_unit_pos);
const next_unit_pos = this_unit_offset + next_offset;
var compile_unit: CompileUnit = undefined;
while ((try seekable.getPos()) < next_unit_pos) {
var die_obj = (try di.parseDie(arena, in, abbrev_table, is_64)) orelse continue;
const after_die_offset = try seekable.getPos();
switch (die_obj.tag_id) {
TAG.compile_unit => {
compile_unit = .{
.version = version,
.is_64 = is_64,
.die = &die_obj,
.pc_range = null,
.str_offsets_base = if (die_obj.getAttr(AT.str_offsets_base)) |fv| try fv.getUInt(usize) else 0,
.addr_base = if (die_obj.getAttr(AT.addr_base)) |fv| try fv.getUInt(usize) else 0,
.rnglists_base = if (die_obj.getAttr(AT.rnglists_base)) |fv| try fv.getUInt(usize) else 0,
.loclists_base = if (die_obj.getAttr(AT.loclists_base)) |fv| try fv.getUInt(usize) else 0,
};
},
TAG.subprogram, TAG.inlined_subroutine, TAG.subroutine, TAG.entry_point => {
const fn_name = x: {
var depth: i32 = 3;
var this_die_obj = die_obj;
// Prevent endless loops
while (depth > 0) : (depth -= 1) {
if (this_die_obj.getAttr(AT.name)) |_| {
const name = try this_die_obj.getAttrString(di, AT.name, di.debug_str, compile_unit);
break :x try allocator.dupe(u8, name);
} else if (this_die_obj.getAttr(AT.abstract_origin)) |_| {
// Follow the DIE it points to and repeat
const ref_offset = try this_die_obj.getAttrRef(AT.abstract_origin);
if (ref_offset > next_offset) return badDwarf();
try seekable.seekTo(this_unit_offset + ref_offset);
this_die_obj = (try di.parseDie(
arena,
in,
abbrev_table,
is_64,
)) orelse return badDwarf();
} else if (this_die_obj.getAttr(AT.specification)) |_| {
// Follow the DIE it points to and repeat
const ref_offset = try this_die_obj.getAttrRef(AT.specification);
if (ref_offset > next_offset) return badDwarf();
try seekable.seekTo(this_unit_offset + ref_offset);
this_die_obj = (try di.parseDie(
arena,
in,
abbrev_table,
is_64,
)) orelse return badDwarf();
} else {
break :x null;
}
}
break :x null;
};
const pc_range = x: {
if (die_obj.getAttrAddr(di, AT.low_pc, compile_unit)) |low_pc| {
if (die_obj.getAttr(AT.high_pc)) |high_pc_value| {
const pc_end = switch (high_pc_value.*) {
FormValue.Address => |value| value,
FormValue.Const => |value| b: {
const offset = try value.asUnsignedLe();
break :b (low_pc + offset);
},
else => return badDwarf(),
};
break :x PcRange{
.start = low_pc,
.end = pc_end,
};
} else {
break :x null;
}
} else |err| {
if (err != error.MissingDebugInfo) return err;
break :x null;
}
};
try di.func_list.append(allocator, Func{
.name = fn_name,
.pc_range = pc_range,
});
},
else => {},
}
try seekable.seekTo(after_die_offset);
}
this_unit_offset += next_offset;
}
}
fn scanAllCompileUnits(di: *DwarfInfo, allocator: mem.Allocator) !void {
var stream = io.fixedBufferStream(di.debug_info);
const in = &stream.reader();
const seekable = &stream.seekableStream();
var this_unit_offset: u64 = 0;
while (this_unit_offset < try seekable.getEndPos()) {
try seekable.seekTo(this_unit_offset);
var is_64: bool = undefined;
const unit_length = try readUnitLength(in, di.endian, &is_64);
if (unit_length == 0) return;
const next_offset = unit_length + (if (is_64) @as(usize, 12) else @as(usize, 4));
const version = try in.readInt(u16, di.endian);
if (version < 2 or version > 5) return badDwarf();
var address_size: u8 = undefined;
var debug_abbrev_offset: u64 = undefined;
if (version >= 5) {
const unit_type = try in.readInt(u8, di.endian);
if (unit_type != UT.compile) return badDwarf();
address_size = try in.readByte();
debug_abbrev_offset = if (is_64)
try in.readInt(u64, di.endian)
else
try in.readInt(u32, di.endian);
} else {
debug_abbrev_offset = if (is_64)
try in.readInt(u64, di.endian)
else
try in.readInt(u32, di.endian);
address_size = try in.readByte();
}
if (address_size != @sizeOf(usize)) return badDwarf();
const compile_unit_pos = try seekable.getPos();
const abbrev_table = try di.getAbbrevTable(allocator, debug_abbrev_offset);
try seekable.seekTo(compile_unit_pos);
const compile_unit_die = try allocator.create(Die);
errdefer allocator.destroy(compile_unit_die);
compile_unit_die.* = (try di.parseDie(allocator, in, abbrev_table, is_64)) orelse
return badDwarf();
if (compile_unit_die.tag_id != TAG.compile_unit) return badDwarf();
var compile_unit: CompileUnit = .{
.version = version,
.is_64 = is_64,
.pc_range = null,
.die = compile_unit_die,
.str_offsets_base = if (compile_unit_die.getAttr(AT.str_offsets_base)) |fv| try fv.getUInt(usize) else 0,
.addr_base = if (compile_unit_die.getAttr(AT.addr_base)) |fv| try fv.getUInt(usize) else 0,
.rnglists_base = if (compile_unit_die.getAttr(AT.rnglists_base)) |fv| try fv.getUInt(usize) else 0,
.loclists_base = if (compile_unit_die.getAttr(AT.loclists_base)) |fv| try fv.getUInt(usize) else 0,
};
compile_unit.pc_range = x: {
if (compile_unit_die.getAttrAddr(di, AT.low_pc, compile_unit)) |low_pc| {
if (compile_unit_die.getAttr(AT.high_pc)) |high_pc_value| {
const pc_end = switch (high_pc_value.*) {
FormValue.Address => |value| value,
FormValue.Const => |value| b: {
const offset = try value.asUnsignedLe();
break :b (low_pc + offset);
},
else => return badDwarf(),
};
break :x PcRange{
.start = low_pc,
.end = pc_end,
};
} else {
break :x null;
}
} else |err| {
if (err != error.MissingDebugInfo) return err;
break :x null;
}
};
try di.compile_unit_list.append(allocator, compile_unit);
this_unit_offset += next_offset;
}
}
pub fn findCompileUnit(di: *DwarfInfo, target_address: u64) !*const CompileUnit {
for (di.compile_unit_list.items) |*compile_unit| {
if (compile_unit.pc_range) |range| {
if (target_address >= range.start and target_address < range.end) return compile_unit;
}
if (di.debug_ranges) |debug_ranges| {
if (compile_unit.die.getAttrSecOffset(AT.ranges)) |ranges_offset| {
var stream = io.fixedBufferStream(debug_ranges);
const in = &stream.reader();
const seekable = &stream.seekableStream();
// All the addresses in the list are relative to the value
// specified by DW_AT.low_pc or to some other value encoded
// in the list itself.
// If no starting value is specified use zero.
var base_address = compile_unit.die.getAttrAddr(di, AT.low_pc, compile_unit.*) catch |err| switch (err) {
error.MissingDebugInfo => @as(u64, 0), // TODO https://github.com/ziglang/zig/issues/11135
else => return err,
};
try seekable.seekTo(ranges_offset);
while (true) {
const begin_addr = try in.readInt(usize, di.endian);
const end_addr = try in.readInt(usize, di.endian);
if (begin_addr == 0 and end_addr == 0) {
break;
}
// This entry selects a new value for the base address
if (begin_addr == math.maxInt(usize)) {
base_address = end_addr;
continue;
}
if (target_address >= base_address + begin_addr and target_address < base_address + end_addr) {
return compile_unit;
}
}
} else |err| {
if (err != error.MissingDebugInfo) return err;
continue;
}
}
}
return missingDwarf();
}
/// Gets an already existing AbbrevTable given the abbrev_offset, or if not found,
/// seeks in the stream and parses it.
fn getAbbrevTable(di: *DwarfInfo, allocator: mem.Allocator, abbrev_offset: u64) !*const AbbrevTable {
for (di.abbrev_table_list.items) |*header| {
if (header.offset == abbrev_offset) {
return &header.table;
}
}
try di.abbrev_table_list.append(allocator, AbbrevTableHeader{
.offset = abbrev_offset,
.table = try di.parseAbbrevTable(allocator, abbrev_offset),
});
return &di.abbrev_table_list.items[di.abbrev_table_list.items.len - 1].table;
}
fn parseAbbrevTable(di: *DwarfInfo, allocator: mem.Allocator, offset: u64) !AbbrevTable {
var stream = io.fixedBufferStream(di.debug_abbrev);
const in = &stream.reader();
const seekable = &stream.seekableStream();
try seekable.seekTo(offset);
var result = AbbrevTable.init(allocator);
errdefer {
for (result.items) |*entry| {
entry.attrs.deinit();
}
result.deinit();
}
while (true) {
const abbrev_code = try leb.readULEB128(u64, in);
if (abbrev_code == 0) return result;
try result.append(AbbrevTableEntry{
.abbrev_code = abbrev_code,
.tag_id = try leb.readULEB128(u64, in),
.has_children = (try in.readByte()) == CHILDREN.yes,
.attrs = std.ArrayList(AbbrevAttr).init(allocator),
});
const attrs = &result.items[result.items.len - 1].attrs;
while (true) {
const attr_id = try leb.readULEB128(u64, in);
const form_id = try leb.readULEB128(u64, in);
if (attr_id == 0 and form_id == 0) break;
// DW_FORM_implicit_const stores its value immediately after the attribute pair :(
const payload = if (form_id == FORM.implicit_const) try leb.readILEB128(i64, in) else undefined;
try attrs.append(AbbrevAttr{
.attr_id = attr_id,
.form_id = form_id,
.payload = payload,
});
}
}
}
fn parseDie(
di: *DwarfInfo,
allocator: mem.Allocator,
in_stream: anytype,
abbrev_table: *const AbbrevTable,
is_64: bool,
) !?Die {
const abbrev_code = try leb.readULEB128(u64, in_stream);
if (abbrev_code == 0) return null;
const table_entry = getAbbrevTableEntry(abbrev_table, abbrev_code) orelse return badDwarf();
var result = Die{
// Lives as long as the Die.
.arena = std.heap.ArenaAllocator.init(allocator),
.tag_id = table_entry.tag_id,
.has_children = table_entry.has_children,
};
try result.attrs.resize(allocator, table_entry.attrs.items.len);
for (table_entry.attrs.items, 0..) |attr, i| {
result.attrs.items[i] = Die.Attr{
.id = attr.attr_id,
.value = try parseFormValue(
result.arena.allocator(),
in_stream,
attr.form_id,
di.endian,
is_64,
),
};
if (attr.form_id == FORM.implicit_const) {
result.attrs.items[i].value.Const.payload = @bitCast(u64, attr.payload);
}
}
return result;
}
pub fn getLineNumberInfo(
di: *DwarfInfo,
allocator: mem.Allocator,
compile_unit: CompileUnit,
target_address: u64,
) !debug.LineInfo {
var stream = io.fixedBufferStream(di.debug_line);
const in = &stream.reader();
const seekable = &stream.seekableStream();
const compile_unit_cwd = try compile_unit.die.getAttrString(di, AT.comp_dir, di.debug_line_str, compile_unit);
const line_info_offset = try compile_unit.die.getAttrSecOffset(AT.stmt_list);
try seekable.seekTo(line_info_offset);
var is_64: bool = undefined;
const unit_length = try readUnitLength(in, di.endian, &is_64);
if (unit_length == 0) {
return missingDwarf();
}
const next_offset = unit_length + (if (is_64) @as(usize, 12) else @as(usize, 4));
const version = try in.readInt(u16, di.endian);
if (version < 2) return badDwarf();
var addr_size: u8 = if (is_64) 8 else 4;
var seg_size: u8 = 0;
if (version >= 5) {
addr_size = try in.readByte();
seg_size = try in.readByte();
}
const prologue_length = if (is_64) try in.readInt(u64, di.endian) else try in.readInt(u32, di.endian);
const prog_start_offset = (try seekable.getPos()) + prologue_length;
const minimum_instruction_length = try in.readByte();
if (minimum_instruction_length == 0) return badDwarf();
if (version >= 4) {
// maximum_operations_per_instruction
_ = try in.readByte();
}
const default_is_stmt = (try in.readByte()) != 0;
const line_base = try in.readByteSigned();
const line_range = try in.readByte();
if (line_range == 0) return badDwarf();
const opcode_base = try in.readByte();
const standard_opcode_lengths = try allocator.alloc(u8, opcode_base - 1);
defer allocator.free(standard_opcode_lengths);
{
var i: usize = 0;
while (i < opcode_base - 1) : (i += 1) {
standard_opcode_lengths[i] = try in.readByte();
}
}
var tmp_arena = std.heap.ArenaAllocator.init(allocator);
defer tmp_arena.deinit();
const arena = tmp_arena.allocator();
var include_directories = std.ArrayList(FileEntry).init(arena);
var file_entries = std.ArrayList(FileEntry).init(arena);
if (version < 5) {
try include_directories.append(.{ .path = compile_unit_cwd });
while (true) {
const dir = try in.readUntilDelimiterAlloc(arena, 0, math.maxInt(usize));
if (dir.len == 0) break;
try include_directories.append(.{ .path = dir });
}
while (true) {
const file_name = try in.readUntilDelimiterAlloc(arena, 0, math.maxInt(usize));
if (file_name.len == 0) break;
const dir_index = try leb.readULEB128(u32, in);
const mtime = try leb.readULEB128(u64, in);
const size = try leb.readULEB128(u64, in);
try file_entries.append(FileEntry{
.path = file_name,
.dir_index = dir_index,
.mtime = mtime,
.size = size,
});
}
} else {
const FileEntFmt = struct {
content_type_code: u8,
form_code: u16,
};
{
var dir_ent_fmt_buf: [10]FileEntFmt = undefined;
const directory_entry_format_count = try in.readByte();
if (directory_entry_format_count > dir_ent_fmt_buf.len) return badDwarf();
for (dir_ent_fmt_buf[0..directory_entry_format_count]) |*ent_fmt| {
ent_fmt.* = .{
.content_type_code = try leb.readULEB128(u8, in),
.form_code = try leb.readULEB128(u16, in),
};
}
const directories_count = try leb.readULEB128(usize, in);
try include_directories.ensureUnusedCapacity(directories_count);
{
var i: usize = 0;
while (i < directories_count) : (i += 1) {
var e: FileEntry = .{ .path = &.{} };
for (dir_ent_fmt_buf[0..directory_entry_format_count]) |ent_fmt| {
const form_value = try parseFormValue(
arena,
in,
ent_fmt.form_code,
di.endian,
is_64,
);
switch (ent_fmt.content_type_code) {
LNCT.path => e.path = try form_value.getString(di.*),
LNCT.directory_index => e.dir_index = try form_value.getUInt(u32),
LNCT.timestamp => e.mtime = try form_value.getUInt(u64),
LNCT.size => e.size = try form_value.getUInt(u64),
LNCT.MD5 => e.md5 = try form_value.getData16(),
else => continue,
}
}
include_directories.appendAssumeCapacity(e);
}
}
}
var file_ent_fmt_buf: [10]FileEntFmt = undefined;
const file_name_entry_format_count = try in.readByte();
if (file_name_entry_format_count > file_ent_fmt_buf.len) return badDwarf();
for (file_ent_fmt_buf[0..file_name_entry_format_count]) |*ent_fmt| {
ent_fmt.* = .{
.content_type_code = try leb.readULEB128(u8, in),
.form_code = try leb.readULEB128(u16, in),
};
}
const file_names_count = try leb.readULEB128(usize, in);
try file_entries.ensureUnusedCapacity(file_names_count);
{
var i: usize = 0;
while (i < file_names_count) : (i += 1) {
var e: FileEntry = .{ .path = &.{} };
for (file_ent_fmt_buf[0..file_name_entry_format_count]) |ent_fmt| {
const form_value = try parseFormValue(
arena,
in,
ent_fmt.form_code,
di.endian,
is_64,
);
switch (ent_fmt.content_type_code) {
LNCT.path => e.path = try form_value.getString(di.*),
LNCT.directory_index => e.dir_index = try form_value.getUInt(u32),
LNCT.timestamp => e.mtime = try form_value.getUInt(u64),
LNCT.size => e.size = try form_value.getUInt(u64),
LNCT.MD5 => e.md5 = try form_value.getData16(),
else => continue,
}
}
file_entries.appendAssumeCapacity(e);
}
}
}
var prog = LineNumberProgram.init(
default_is_stmt,
include_directories.items,
target_address,
version,
);
try seekable.seekTo(prog_start_offset);
const next_unit_pos = line_info_offset + next_offset;
while ((try seekable.getPos()) < next_unit_pos) {
const opcode = try in.readByte();
if (opcode == LNS.extended_op) {
const op_size = try leb.readULEB128(u64, in);
if (op_size < 1) return badDwarf();
var sub_op = try in.readByte();
switch (sub_op) {
LNE.end_sequence => {
prog.end_sequence = true;
if (try prog.checkLineMatch(allocator, file_entries.items)) |info| return info;
prog.reset();
},
LNE.set_address => {
const addr = try in.readInt(usize, di.endian);
prog.address = addr;
},
LNE.define_file => {
const path = try in.readUntilDelimiterAlloc(arena, 0, math.maxInt(usize));
const dir_index = try leb.readULEB128(u32, in);
const mtime = try leb.readULEB128(u64, in);
const size = try leb.readULEB128(u64, in);
try file_entries.append(FileEntry{
.path = path,
.dir_index = dir_index,
.mtime = mtime,
.size = size,
});
},
else => {
const fwd_amt = math.cast(isize, op_size - 1) orelse return badDwarf();
try seekable.seekBy(fwd_amt);
},
}
} else if (opcode >= opcode_base) {
// special opcodes
const adjusted_opcode = opcode - opcode_base;
const inc_addr = minimum_instruction_length * (adjusted_opcode / line_range);
const inc_line = @as(i32, line_base) + @as(i32, adjusted_opcode % line_range);
prog.line += inc_line;
prog.address += inc_addr;
if (try prog.checkLineMatch(allocator, file_entries.items)) |info| return info;
prog.basic_block = false;
} else {
switch (opcode) {
LNS.copy => {
if (try prog.checkLineMatch(allocator, file_entries.items)) |info| return info;
prog.basic_block = false;
},
LNS.advance_pc => {
const arg = try leb.readULEB128(usize, in);
prog.address += arg * minimum_instruction_length;
},
LNS.advance_line => {
const arg = try leb.readILEB128(i64, in);
prog.line += arg;
},
LNS.set_file => {
const arg = try leb.readULEB128(usize, in);
prog.file = arg;
},
LNS.set_column => {
const arg = try leb.readULEB128(u64, in);
prog.column = arg;
},
LNS.negate_stmt => {
prog.is_stmt = !prog.is_stmt;
},
LNS.set_basic_block => {
prog.basic_block = true;
},
LNS.const_add_pc => {
const inc_addr = minimum_instruction_length * ((255 - opcode_base) / line_range);
prog.address += inc_addr;
},
LNS.fixed_advance_pc => {
const arg = try in.readInt(u16, di.endian);
prog.address += arg;
},
LNS.set_prologue_end => {},
else => {
if (opcode - 1 >= standard_opcode_lengths.len) return badDwarf();
const len_bytes = standard_opcode_lengths[opcode - 1];
try seekable.seekBy(len_bytes);
},
}
}
}
return missingDwarf();
}
fn getString(di: DwarfInfo, offset: u64) ![]const u8 {
return getStringGeneric(di.debug_str, offset);
}
fn getLineString(di: DwarfInfo, offset: u64) ![]const u8 {
return getStringGeneric(di.debug_line_str, offset);
}
};
/// Initialize DWARF info. The caller has the responsibility to initialize most
/// the DwarfInfo fields before calling.
pub fn openDwarfDebugInfo(di: *DwarfInfo, allocator: mem.Allocator) !void {
try di.scanAllFunctions(allocator);
try di.scanAllCompileUnits(allocator);
}
/// This function is to make it handy to comment out the return and make it
/// into a crash when working on this file.
fn badDwarf() error{InvalidDebugInfo} {
//std.os.abort(); // can be handy to uncomment when working on this file
return error.InvalidDebugInfo;
}
fn missingDwarf() error{MissingDebugInfo} {
//std.os.abort(); // can be handy to uncomment when working on this file
return error.MissingDebugInfo;
}
fn getStringGeneric(opt_str: ?[]const u8, offset: u64) ![:0]const u8 {
const str = opt_str orelse return badDwarf();
if (offset > str.len) return badDwarf();
const casted_offset = math.cast(usize, offset) orelse return badDwarf();
// Valid strings always have a terminating zero byte
const last = mem.indexOfScalarPos(u8, str, casted_offset, 0) orelse return badDwarf();
return str[casted_offset..last :0];
}
Reference in a new issue View git blame Copy permalink