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1/*2 * Double-precision vector sin function.3 *4 * Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.5 * See https://llvm.org/LICENSE.txt for license information.6 * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception7 */8 9#include "mathlib.h"10#include "v_math.h"11#if V_SUPPORTED12 13static const double Poly[] = {14/* worst-case error is 3.5 ulp.15 abs error: 0x1.be222a58p-53 in [-pi/2, pi/2]. */16-0x1.9f4a9c8b21dc9p-41,17 0x1.60e88a10163f2p-33,18-0x1.ae6361b7254e7p-26,19 0x1.71de382e8d62bp-19,20-0x1.a01a019aeb4ffp-13,21 0x1.111111110b25ep-7,22-0x1.55555555554c3p-3,23};24 25#define C7 v_f64 (Poly[0])26#define C6 v_f64 (Poly[1])27#define C5 v_f64 (Poly[2])28#define C4 v_f64 (Poly[3])29#define C3 v_f64 (Poly[4])30#define C2 v_f64 (Poly[5])31#define C1 v_f64 (Poly[6])32 33#define InvPi v_f64 (0x1.45f306dc9c883p-2)34#define Pi1 v_f64 (0x1.921fb54442d18p+1)35#define Pi2 v_f64 (0x1.1a62633145c06p-53)36#define Pi3 v_f64 (0x1.c1cd129024e09p-106)37#define Shift v_f64 (0x1.8p52)38#define RangeVal v_f64 (0x1p23)39#define AbsMask v_u64 (0x7fffffffffffffff)40 41VPCS_ATTR42__attribute__ ((noinline)) static v_f64_t43specialcase (v_f64_t x, v_f64_t y, v_u64_t cmp)44{45 return v_call_f64 (sin, x, y, cmp);46}47 48VPCS_ATTR49v_f64_t50V_NAME(sin) (v_f64_t x)51{52 v_f64_t n, r, r2, y;53 v_u64_t sign, odd, cmp;54 55 r = v_as_f64_u64 (v_as_u64_f64 (x) & AbsMask);56 sign = v_as_u64_f64 (x) & ~AbsMask;57 cmp = v_cond_u64 (v_as_u64_f64 (r) >= v_as_u64_f64 (RangeVal));58 59 /* n = rint(|x|/pi). */60 n = v_fma_f64 (InvPi, r, Shift);61 odd = v_as_u64_f64 (n) << 63;62 n -= Shift;63 64 /* r = |x| - n*pi (range reduction into -pi/2 .. pi/2). */65 r = v_fma_f64 (-Pi1, n, r);66 r = v_fma_f64 (-Pi2, n, r);67 r = v_fma_f64 (-Pi3, n, r);68 69 /* sin(r) poly approx. */70 r2 = r * r;71 y = v_fma_f64 (C7, r2, C6);72 y = v_fma_f64 (y, r2, C5);73 y = v_fma_f64 (y, r2, C4);74 y = v_fma_f64 (y, r2, C3);75 y = v_fma_f64 (y, r2, C2);76 y = v_fma_f64 (y, r2, C1);77 y = v_fma_f64 (y * r2, r, r);78 79 /* sign. */80 y = v_as_f64_u64 (v_as_u64_f64 (y) ^ sign ^ odd);81 82 if (unlikely (v_any_u64 (cmp)))83 return specialcase (x, y, cmp);84 return y;85}86VPCS_ALIAS87#endif88