zig/lib/compiler_rt/bcmp.zig
Luuk de Gram f5edaa96dd compiler_rt: Move mem implementations from c.zig
This moves functions that LLVM generates calls to,
to the compiler_rt implementation itself, rather than c.zig.
This is a prerequisite for native backends to link with compiler-rt.
This also allows native backends to generate calls to `memcpy` and the like.
2022-10-15 07:02:38 -07:00

31 lines
840 B
Zig

const std = @import("std");
const common = @import("./common.zig");
comptime {
@export(bcmp, .{ .name = "bcmp", .linkage = common.linkage });
}
pub fn bcmp(vl: [*]allowzero const u8, vr: [*]allowzero const u8, n: usize) callconv(.C) c_int {
@setRuntimeSafety(false);
var index: usize = 0;
while (index != n) : (index += 1) {
if (vl[index] != vr[index]) {
return 1;
}
}
return 0;
}
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 };
try std.testing.expect(bcmp(base_arr[0..], arr1[0..], base_arr.len) == 0);
try std.testing.expect(bcmp(base_arr[0..], arr2[0..], base_arr.len) != 0);
try std.testing.expect(bcmp(base_arr[0..], arr3[0..], base_arr.len) != 0);
}