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0fe3fd01dd
The compiler actually doesn't need any functional changes for this: Sema does reification based on the tag indices of `std.builtin.Type` already! So, no zig1.wasm update is necessary. This change is necessary to disallow name clashes between fields and decls on a type, which is a prerequisite of #9938.
26 lines
1.1 KiB
Zig
26 lines
1.1 KiB
Zig
const std = @import("../std.zig");
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const math = std.math;
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const expect = std.testing.expect;
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/// Returns a value with the magnitude of `magnitude` and the sign of `sign`.
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pub fn copysign(magnitude: anytype, sign: @TypeOf(magnitude)) @TypeOf(magnitude) {
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const T = @TypeOf(magnitude);
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const TBits = std.meta.Int(.unsigned, @typeInfo(T).float.bits);
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const sign_bit_mask = @as(TBits, 1) << (@bitSizeOf(T) - 1);
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const mag = @as(TBits, @bitCast(magnitude)) & ~sign_bit_mask;
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const sgn = @as(TBits, @bitCast(sign)) & sign_bit_mask;
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return @as(T, @bitCast(mag | sgn));
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}
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test copysign {
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inline for ([_]type{ f16, f32, f64, f80, f128 }) |T| {
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try expect(copysign(@as(T, 1.0), @as(T, 1.0)) == 1.0);
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try expect(copysign(@as(T, 2.0), @as(T, -2.0)) == -2.0);
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try expect(copysign(@as(T, -3.0), @as(T, 3.0)) == 3.0);
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try expect(copysign(@as(T, -4.0), @as(T, -4.0)) == -4.0);
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try expect(copysign(@as(T, 5.0), @as(T, -500.0)) == -5.0);
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try expect(copysign(math.inf(T), @as(T, -0.0)) == -math.inf(T));
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try expect(copysign(@as(T, 6.0), -math.nan(T)) == -6.0);
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}
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}
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