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c56663dee8
- use negXi2.zig to prevent confusion with negXf2.zig - used for size optimized builds and machines without carry instruction - tests: special cases 0, -INT_MIN * use divTrunc range and shift with constant offsets See #1290
34 lines
819 B
Zig
34 lines
819 B
Zig
const std = @import("std");
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const builtin = @import("builtin");
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// neg - negate (the number)
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// - negXi2_generic for unoptimized little and big endian
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// sfffffff = 2^31-1
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// two's complement inverting bits and add 1 would result in -INT_MIN == 0
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// => -INT_MIN = -2^31 forbidden
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// * size optimized builds
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// * machines that dont support carry operations
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fn negXi2_generic(comptime T: type) fn (a: T) callconv(.C) T {
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return struct {
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fn f(a: T) callconv(.C) T {
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@setRuntimeSafety(builtin.is_test);
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return -a;
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}
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}.f;
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}
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pub const __negsi2 = negXi2_generic(i32);
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pub const __negdi2 = negXi2_generic(i64);
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pub const __negti2 = negXi2_generic(i128);
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test {
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_ = @import("negsi2_test.zig");
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_ = @import("negdi2_test.zig");
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_ = @import("negti2_test.zig");
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}
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