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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
commit698f8c2f01ea549d77d7dc3338a12e04c11057b9 (patch)
tree173a775858bd501c378080a10dca74132f05bc50 /vendor/libm/src/math/cosf.rs
parentInitial commit. (diff)
downloadrustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.tar.xz
rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.zip
Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'vendor/libm/src/math/cosf.rs')
-rw-r--r--vendor/libm/src/math/cosf.rs84
1 files changed, 84 insertions, 0 deletions
diff --git a/vendor/libm/src/math/cosf.rs b/vendor/libm/src/math/cosf.rs
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+++ b/vendor/libm/src/math/cosf.rs
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+/* origin: FreeBSD /usr/src/lib/msun/src/s_cosf.c */
+/*
+ * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
+ * Optimized by Bruce D. Evans.
+ */
+/*
+ * ====================================================
+ * 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::{k_cosf, k_sinf, rem_pio2f};
+
+use core::f64::consts::FRAC_PI_2;
+
+/* Small multiples of pi/2 rounded to double precision. */
+const C1_PIO2: f64 = 1. * FRAC_PI_2; /* 0x3FF921FB, 0x54442D18 */
+const C2_PIO2: f64 = 2. * FRAC_PI_2; /* 0x400921FB, 0x54442D18 */
+const C3_PIO2: f64 = 3. * FRAC_PI_2; /* 0x4012D97C, 0x7F3321D2 */
+const C4_PIO2: f64 = 4. * FRAC_PI_2; /* 0x401921FB, 0x54442D18 */
+
+#[inline]
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn cosf(x: f32) -> f32 {
+ let x64 = x as f64;
+
+ let x1p120 = f32::from_bits(0x7b800000); // 0x1p120f === 2 ^ 120
+
+ let mut ix = x.to_bits();
+ let sign = (ix >> 31) != 0;
+ ix &= 0x7fffffff;
+
+ if ix <= 0x3f490fda {
+ /* |x| ~<= pi/4 */
+ if ix < 0x39800000 {
+ /* |x| < 2**-12 */
+ /* raise inexact if x != 0 */
+ force_eval!(x + x1p120);
+ return 1.;
+ }
+ return k_cosf(x64);
+ }
+ if ix <= 0x407b53d1 {
+ /* |x| ~<= 5*pi/4 */
+ if ix > 0x4016cbe3 {
+ /* |x| ~> 3*pi/4 */
+ return -k_cosf(if sign { x64 + C2_PIO2 } else { x64 - C2_PIO2 });
+ } else if sign {
+ return k_sinf(x64 + C1_PIO2);
+ } else {
+ return k_sinf(C1_PIO2 - x64);
+ }
+ }
+ if ix <= 0x40e231d5 {
+ /* |x| ~<= 9*pi/4 */
+ if ix > 0x40afeddf {
+ /* |x| ~> 7*pi/4 */
+ return k_cosf(if sign { x64 + C4_PIO2 } else { x64 - C4_PIO2 });
+ } else if sign {
+ return k_sinf(-x64 - C3_PIO2);
+ } else {
+ return k_sinf(x64 - C3_PIO2);
+ }
+ }
+
+ /* cos(Inf or NaN) is NaN */
+ if ix >= 0x7f800000 {
+ return x - x;
+ }
+
+ /* general argument reduction needed */
+ let (n, y) = rem_pio2f(x);
+ match n & 3 {
+ 0 => k_cosf(y),
+ 1 => k_sinf(-y),
+ 2 => -k_cosf(y),
+ _ => k_sinf(y),
+ }
+}