39 lines
1.3 KiB
Zig

// SPDX-License-Identifier: MIT
// Copyright (c) 2015-2020 Zig Contributors
// This file is part of [zig](https://ziglang.org/), which is MIT licensed.
// The MIT license requires this copyright notice to be included in all copies
// and substantial portions of the software.
// Ported from:
//
// https://github.com/llvm/llvm-project/blob/2ffb1b0413efa9a24eb3c49e710e36f92e2cb50b/compiler-rt/lib/builtins/modti3.c
const udivmod = @import("udivmod.zig").udivmod;
const builtin = @import("builtin");
const compiler_rt = @import("../compiler_rt.zig");
pub fn __modti3(a: i128, b: i128) callconv(.C) i128 {
@setRuntimeSafety(builtin.is_test);
const s_a = a >> (128 - 1); // s = a < 0 ? -1 : 0
const s_b = b >> (128 - 1); // s = b < 0 ? -1 : 0
const an = (a ^ s_a) -% s_a; // negate if s == -1
const bn = (b ^ s_b) -% s_b; // negate if s == -1
var r: u128 = undefined;
_ = udivmod(u128, @bitCast(u128, an), @bitCast(u128, bn), &r);
return (@bitCast(i128, r) ^ s_a) -% s_a; // negate if s == -1
}
const v128 = @import("std").meta.Vector(2, u64);
pub fn __modti3_windows_x86_64(a: v128, b: v128) callconv(.C) v128 {
return @bitCast(v128, @call(.{ .modifier = .always_inline }, __modti3, .{
@bitCast(i128, a),
@bitCast(i128, b),
}));
}
test "import modti3" {
_ = @import("modti3_test.zig");
}