zig/lib/compiler_rt/negv.zig
mlugg f26dda2117 all: migrate code to new cast builtin syntax
Most of this migration was performed automatically with `zig fmt`. There
were a few exceptions which I had to manually fix:

* `@alignCast` and `@addrSpaceCast` cannot be automatically rewritten
* `@truncate`'s fixup is incorrect for vectors
* Test cases are not formatted, and their error locations change
2023-06-24 16:56:39 -07:00

47 lines
1.3 KiB
Zig

//! negv - negate oVerflow
//! * @panic, if result can not be represented
//! - negvXi4_generic for unoptimized version
const std = @import("std");
const builtin = @import("builtin");
const common = @import("common.zig");
pub const panic = common.panic;
comptime {
@export(__negvsi2, .{ .name = "__negvsi2", .linkage = common.linkage, .visibility = common.visibility });
@export(__negvdi2, .{ .name = "__negvdi2", .linkage = common.linkage, .visibility = common.visibility });
@export(__negvti2, .{ .name = "__negvti2", .linkage = common.linkage, .visibility = common.visibility });
}
pub fn __negvsi2(a: i32) callconv(.C) i32 {
return negvXi(i32, a);
}
pub fn __negvdi2(a: i64) callconv(.C) i64 {
return negvXi(i64, a);
}
pub fn __negvti2(a: i128) callconv(.C) i128 {
return negvXi(i128, a);
}
inline fn negvXi(comptime ST: type, a: ST) ST {
const UT = switch (ST) {
i32 => u32,
i64 => u64,
i128 => u128,
else => unreachable,
};
const N: UT = @bitSizeOf(ST);
const min: ST = @as(ST, @bitCast((@as(UT, 1) << (N - 1))));
if (a == min)
@panic("compiler_rt negv: overflow");
return -a;
}
test {
_ = @import("negvsi2_test.zig");
_ = @import("negvdi2_test.zig");
_ = @import("negvti2_test.zig");
}