Nixyri/zig
1
0
Fork 0
mirror of https://github.com/ziglang/zig.git synced 2025-02-04 12:01:18 +00:00
Code Issues Packages Projects Releases Wiki Activity

add bcmp implementation as LLVM 9 now emits those

Browse Source 
The optimizer will now convert calls to memcmp into a calls to bcmp
in some circumstances. Users who are building freestanding code (not
depending on the platform’s libc) without specifying -ffreestanding may
need to either pass -fno-builtin-bcmp, or provide a bcmp function.

http://llvm.org/docs/ReleaseNotes.html#non-comprehensive-list-of-changes-in-this-release
This commit is contained in:
Shawn Landden 2019-06-08 14:34:15 -05:00 committed by Andrew Kelley
parent 404e4b0268
commit 720ed74413
1 changed files with 26 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
std/special/c.zig
View File

@ -136,8 +136,32 @@ test "test_memcmp" {
const arr3 = []u8{ 1, 2, 1 };
std.testing.expect(memcmp(base_arr[0..].ptr, arr1[0..].ptr, base_arr.len) == 0);
std.testing.expect(memcmp(base_arr[0..].ptr, arr2[0..].ptr, base_arr.len) == 1);
std.testing.expect(memcmp(base_arr[0..].ptr, arr3[0..].ptr, base_arr.len) == -1);
std.testing.expect(memcmp(base_arr[0..].ptr, arr2[0..].ptr, base_arr.len) > 0);
std.testing.expect(memcmp(base_arr[0..].ptr, arr3[0..].ptr, base_arr.len) < 0);
}
export fn bcmp(vl: [*]allowzero const u8, vr: [*]allowzero const u8, n: usize) isize {
@setRuntimeSafety(false);
var index: usize = 0;
while (index != n) : (index += 1) {
if (vl[index] != vr[index]) {
return 1;
}
}
return 0;
}
test "test_bcmp" {
const base_arr = []u8{ 1, 1, 1 };
const arr1 = []u8{ 1, 1, 1 };
const arr2 = []u8{ 1, 0, 1 };
const arr3 = []u8{ 1, 2, 1 };
std.testing.expect(bcmp(base_arr[0..].ptr, arr1[0..].ptr, base_arr.len) == 0);
std.testing.expect(bcmp(base_arr[0..].ptr, arr2[0..].ptr, base_arr.len) != 0);
std.testing.expect(bcmp(base_arr[0..].ptr, arr3[0..].ptr, base_arr.len) != 0);
}
comptime {