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6b14c58f63
This improves readability as well as compatibility with stage2. Most of compiler-rt is now enabled for stage2 with just a few functions disabled (until stage2 passes more behavior tests).
37 lines
869 B
Zig
37 lines
869 B
Zig
// negv - negate oVerflow
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// * @panic, if result can not be represented
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// - negvXi4_generic for unoptimized version
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// assume -0 == 0 is gracefully handled by the hardware
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inline fn negvXi(comptime ST: type, a: ST) ST {
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const UT = switch (ST) {
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i32 => u32,
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i64 => u64,
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i128 => u128,
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else => unreachable,
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};
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const N: UT = @bitSizeOf(ST);
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const min: ST = @bitCast(ST, (@as(UT, 1) << (N - 1)));
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if (a == min)
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@panic("compiler_rt negv: overflow");
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return -a;
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}
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pub fn __negvsi2(a: i32) callconv(.C) i32 {
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return negvXi(i32, a);
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}
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pub fn __negvdi2(a: i64) callconv(.C) i64 {
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return negvXi(i64, a);
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}
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pub fn __negvti2(a: i128) callconv(.C) i128 {
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return negvXi(i128, a);
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}
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test {
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_ = @import("negvsi2_test.zig");
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_ = @import("negvdi2_test.zig");
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_ = @import("negvti2_test.zig");
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}
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