improve(math): Add fast path for x % 1.0 and x % -1.0 #1447
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MaxGraey
commented
Aug 24, 2020
| // TODO: move this rule to compiler's optimization pass | ||
| if (builtin_abs<f64>(y) == 1.0) { | ||
| // x % 1, x % -1 ==> sign(x) * abs(x - trunc(x)) | ||
| return builtin_copysign<f64>(x - builtin_trunc<f64>(x), x); |
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copysign necessary for handling -0.0 % 1.0 -> -0.0 edge case
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Actually it could be apply for any pow of two modulo divisor |
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🎉 This PR is included in version 0.14.10 🎉 The release is available on: Your semantic-release bot 📦🚀 |
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Fast path:
It similar what we already do for Math.pow(x, 2.0) and etc.
In future it could be generalized to
x % C_pot=>copysign(x - C_pot * trunc(x * (1 / C_pot)), x),where C_pot is pow of two constant.