From 698f8c2f01ea549d77d7dc3338a12e04c11057b9 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 17 Apr 2024 14:02:58 +0200 Subject: Adding upstream version 1.64.0+dfsg1. Signed-off-by: Daniel Baumann --- vendor/compiler_builtins/libm/src/math/sincos.rs | 133 +++++++++++++++++++++++ 1 file changed, 133 insertions(+) create mode 100644 vendor/compiler_builtins/libm/src/math/sincos.rs (limited to 'vendor/compiler_builtins/libm/src/math/sincos.rs') diff --git a/vendor/compiler_builtins/libm/src/math/sincos.rs b/vendor/compiler_builtins/libm/src/math/sincos.rs new file mode 100644 index 000000000..4ab588412 --- /dev/null +++ b/vendor/compiler_builtins/libm/src/math/sincos.rs @@ -0,0 +1,133 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/s_sin.c */ +/* + * ==================================================== + * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. + * + * Developed at SunPro, a Sun Microsystems, Inc. business. + * Permission to use, copy, modify, and distribute this + * software is freely granted, provided that this notice + * is preserved. + * ==================================================== + */ + +use super::{get_high_word, k_cos, k_sin, rem_pio2}; + +pub fn sincos(x: f64) -> (f64, f64) { + let s: f64; + let c: f64; + let mut ix: u32; + + ix = get_high_word(x); + ix &= 0x7fffffff; + + /* |x| ~< pi/4 */ + if ix <= 0x3fe921fb { + /* if |x| < 2**-27 * sqrt(2) */ + if ix < 0x3e46a09e { + /* raise inexact if x!=0 and underflow if subnormal */ + let x1p120 = f64::from_bits(0x4770000000000000); // 0x1p120 == 2^120 + if ix < 0x00100000 { + force_eval!(x / x1p120); + } else { + force_eval!(x + x1p120); + } + return (x, 1.0); + } + return (k_sin(x, 0.0, 0), k_cos(x, 0.0)); + } + + /* sincos(Inf or NaN) is NaN */ + if ix >= 0x7ff00000 { + let rv = x - x; + return (rv, rv); + } + + /* argument reduction needed */ + let (n, y0, y1) = rem_pio2(x); + s = k_sin(y0, y1, 1); + c = k_cos(y0, y1); + match n & 3 { + 0 => (s, c), + 1 => (c, -s), + 2 => (-s, -c), + 3 => (-c, s), + #[cfg(debug_assertions)] + _ => unreachable!(), + #[cfg(not(debug_assertions))] + _ => (0.0, 1.0), + } +} + +// These tests are based on those from sincosf.rs +#[cfg(test)] +mod tests { + use super::sincos; + + const TOLERANCE: f64 = 1e-6; + + #[test] + fn with_pi() { + let (s, c) = sincos(core::f64::consts::PI); + assert!( + (s - 0.0).abs() < TOLERANCE, + "|{} - {}| = {} >= {}", + s, + 0.0, + (s - 0.0).abs(), + TOLERANCE + ); + assert!( + (c + 1.0).abs() < TOLERANCE, + "|{} + {}| = {} >= {}", + c, + 1.0, + (s + 1.0).abs(), + TOLERANCE + ); + } + + #[test] + fn rotational_symmetry() { + use core::f64::consts::PI; + const N: usize = 24; + for n in 0..N { + let theta = 2. * PI * (n as f64) / (N as f64); + let (s, c) = sincos(theta); + let (s_plus, c_plus) = sincos(theta + 2. * PI); + let (s_minus, c_minus) = sincos(theta - 2. * PI); + + assert!( + (s - s_plus).abs() < TOLERANCE, + "|{} - {}| = {} >= {}", + s, + s_plus, + (s - s_plus).abs(), + TOLERANCE + ); + assert!( + (s - s_minus).abs() < TOLERANCE, + "|{} - {}| = {} >= {}", + s, + s_minus, + (s - s_minus).abs(), + TOLERANCE + ); + assert!( + (c - c_plus).abs() < TOLERANCE, + "|{} - {}| = {} >= {}", + c, + c_plus, + (c - c_plus).abs(), + TOLERANCE + ); + assert!( + (c - c_minus).abs() < TOLERANCE, + "|{} - {}| = {} >= {}", + c, + c_minus, + (c - c_minus).abs(), + TOLERANCE + ); + } + } +} -- cgit v1.2.3