25 lines
560 B
Zig
25 lines
560 B
Zig
const builtin = @import("builtin");
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const std = @import("std");
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const twop52: f64 = 0x1.0p52;
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const twop84: f64 = 0x1.0p84;
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const twop84_plus_twop52: f64 = 0x1.00000001p84;
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pub extern fn __floatundidf(a: u64) f64 {
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@setRuntimeSafety(builtin.is_test);
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if (a == 0) return 0;
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var high = @bitCast(u64, twop84);
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var low = @bitCast(u64, twop52);
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high |= a >> 32;
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low |= a & 0xFFFFFFFF;
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return (@bitCast(f64, high) - twop84_plus_twop52) + @bitCast(f64, low);
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}
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test "import floatundidf" {
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_ = @import("floatundidf_test.zig");
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}
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