mirror of
https://codeberg.org/ziglang/zig.git
synced 2025-12-06 05:44:20 +00:00
ec95e00e28
stage2: change logic for detecting whether the main package is inside
the std package. Previously it relied on realpath() which is not portable.
This uses resolve() which is how imports already work.
* stage2: fix cleanup bug when creating Module
* flatten lib/std/special/* to lib/*
- this was motivated by making main_pkg_is_inside_std false for
compiler_rt & friends.
* rename "mini libc" to "universal libc"
38 lines
1.3 KiB
Zig
38 lines
1.3 KiB
Zig
const builtin = @import("builtin");
|
|
|
|
// addo - add overflow
|
|
// * return a+%b.
|
|
// * return if a+b overflows => 1 else => 0
|
|
// - addoXi4_generic as default
|
|
|
|
inline fn addoXi4_generic(comptime ST: type, a: ST, b: ST, overflow: *c_int) ST {
|
|
@setRuntimeSafety(builtin.is_test);
|
|
overflow.* = 0;
|
|
var sum: ST = a +% b;
|
|
// Hackers Delight: section Overflow Detection, subsection Signed Add/Subtract
|
|
// Let sum = a +% b == a + b + carry == wraparound addition.
|
|
// Overflow in a+b+carry occurs, iff a and b have opposite signs
|
|
// and the sign of a+b+carry is the same as a (or equivalently b).
|
|
// Slower routine: res = ~(a ^ b) & ((sum ^ a)
|
|
// Faster routine: res = (sum ^ a) & (sum ^ b)
|
|
// Overflow occured, iff (res < 0)
|
|
if (((sum ^ a) & (sum ^ b)) < 0)
|
|
overflow.* = 1;
|
|
return sum;
|
|
}
|
|
|
|
pub fn __addosi4(a: i32, b: i32, overflow: *c_int) callconv(.C) i32 {
|
|
return addoXi4_generic(i32, a, b, overflow);
|
|
}
|
|
pub fn __addodi4(a: i64, b: i64, overflow: *c_int) callconv(.C) i64 {
|
|
return addoXi4_generic(i64, a, b, overflow);
|
|
}
|
|
pub fn __addoti4(a: i128, b: i128, overflow: *c_int) callconv(.C) i128 {
|
|
return addoXi4_generic(i128, a, b, overflow);
|
|
}
|
|
|
|
test {
|
|
_ = @import("addosi4_test.zig");
|
|
_ = @import("addodi4_test.zig");
|
|
_ = @import("addoti4_test.zig");
|
|
}
|