/* * Single-precision sin/cos function. * * Copyright (c) 2018-2019, Arm Limited. * SPDX-License-Identifier: MIT */ #include #include #include "math_config.h" #include "sincosf.h" /* Fast sincosf implementation. Worst-case ULP is 0.5607, maximum relative error is 0.5303 * 2^-23. A single-step range reduction is used for small values. Large inputs have their range reduced using fast integer arithmetic. */ void sincosf (float y, float *sinp, float *cosp) { double x = y; double s; int n; const sincos_t *p = &__sincosf_table[0]; if (abstop12 (y) < abstop12 (pio4f)) { double x2 = x * x; if (unlikely (abstop12 (y) < abstop12 (0x1p-12f))) { if (unlikely (abstop12 (y) < abstop12 (0x1p-126f))) /* Force underflow for tiny y. */ force_eval_float (x2); *sinp = y; *cosp = 1.0f; return; } sincosf_poly (x, x2, p, 0, sinp, cosp); } else if (abstop12 (y) < abstop12 (120.0f)) { x = reduce_fast (x, p, &n); /* Setup the signs for sin and cos. */ s = p->sign[n & 3]; if (n & 2) p = &__sincosf_table[1]; sincosf_poly (x * s, x * x, p, n, sinp, cosp); } else if (likely (abstop12 (y) < abstop12 (INFINITY))) { uint32_t xi = asuint (y); int sign = xi >> 31; x = reduce_large (xi, &n); /* Setup signs for sin and cos - include original sign. */ s = p->sign[(n + sign) & 3]; if ((n + sign) & 2) p = &__sincosf_table[1]; sincosf_poly (x * s, x * x, p, n, sinp, cosp); } else { /* Return NaN if Inf or NaN for both sin and cos. */ *sinp = *cosp = y - y; #if WANT_ERRNO /* Needed to set errno for +-Inf, the add is a hack to work around a gcc register allocation issue: just passing y affects code generation in the fast path. */ __math_invalidf (y + y); #endif } }