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8eeb7de8a2
The left shift overflows for 'int', use uint32_t instead. It syncs with CORE-MATH commit bbfabd993a71b049c210b0febfd06d18369fadc1. Checked on aarch64-linux-gnu, x86_64-linux-gnu, and i686-linux-gnu. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
82 lines
2.6 KiB
C
82 lines
2.6 KiB
C
/* Correctly-rounded cosine of binary32 value for angles in half-revolutions
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Copyright (c) 2022-2025 Alexei Sibidanov.
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The original version of this file was copied from the CORE-MATH
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project (src/binary32/cospi/cospif.c, revision bbfabd99).
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Permission is hereby granted, free of charge, to any person obtaining a copy
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of this software and associated documentation files (the "Software"), to deal
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in the Software without restriction, including without limitation the rights
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to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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copies of the Software, and to permit persons to whom the Software is
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furnished to do so, subject to the following conditions:
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The above copyright notice and this permission notice shall be included in all
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copies or substantial portions of the Software.
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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SOFTWARE.
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*/
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#include <math.h>
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#include <stdint.h>
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#include <libm-alias-float.h>
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#include "s_sincospif_data.h"
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#include "math_config.h"
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float
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__cospif (float x)
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{
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uint32_t ix = asuint (x);
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int32_t e = (ix >> 23) & 0xff;
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if (__glibc_unlikely (e == 0xff))
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{
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if (!(ix << 9))
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return __math_invalidf (x);
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return x + x; /* nan */
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}
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int32_t m = (ix & ~0u >> 9) | 1 << 23;
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int32_t s = 143 - e;
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int32_t p = e - 112;
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if (__glibc_unlikely (p < 0)) /* |x| < 2^-15 */
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{
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uint32_t ax = ix & (~0u>>1);
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/* Warning: -0x1.3bd3ccp+2f * x underflows for |x| < 0x1.9f03p-129 */
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if (ax >= 0x19f030u)
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return fmaf (-0x1.3bd3ccp+2f * x, x, 1.0f);
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else /* |x| < 0x1.9f03p-129 */
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return fmaf (-x, x, 1.0f);
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}
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if (__glibc_unlikely (p > 31))
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{
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if (__glibc_unlikely (p > 63))
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return 1.0f;
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int32_t iq = (uint32_t)m << (p - 32);
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return S[(iq + 32) & 127];
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}
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int32_t k = (uint32_t)m << p;
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if (__glibc_unlikely (k == 0))
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{
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int32_t iq = m >> (32 - p);
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return S[(iq + 32) & 127];
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}
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double z = k;
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double z2 = z * z;
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double fs = SN[0] + z2 * (SN[1] + z2 * SN[2]);
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double fc = CN[0] + z2 * (CN[1] + z2 * CN[2]);
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uint32_t iq = m >> s;
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iq = (iq + 1) >> 1;
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uint32_t is = iq & 127, ic = (iq + 32) & 127;
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double ts = S[ic], tc = S[is];
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double r = ts + (ts * z2) * fc - (tc * z) * fs;
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return r;
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}
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libm_alias_float (__cospi, cospi)
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