/* * Single-precision sin function. * * Copyright (c) 2018, Arm Limited. * SPDX-License-Identifier: MIT */ #if WANT_SINGLEPREC #include "single/s_sinf.c" #else #include <math.h> #include "math_config.h" #include "sincosf.h" /* Fast sinf 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. */ float sinf (float y) { double x = y; double s; int n; const sincos_t *p = &__sincosf_table[0]; if (abstop12 (y) < abstop12 (pio4)) { s = x * x; if (unlikely (abstop12 (y) < abstop12 (0x1p-12f))) { if (unlikely (abstop12 (y) < abstop12 (0x1p-126f))) /* Force underflow for tiny y. */ force_eval_float (s); return y; } return sinf_poly (x, s, p, 0); } else if (likely (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]; return sinf_poly (x * s, x * x, p, n); } else if (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]; return sinf_poly (x * s, x * x, p, n); } else return __math_invalidf (y); } #endif