sinf.cpp
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//===-- Single-precision sin function -------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "math_utils.h"
#include "sincosf_utils.h"
#include "include/math.h"
#include "src/__support/common.h"
#include <stdint.h>
namespace __llvm_libc {
// 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 LLVM_LIBC_ENTRYPOINT(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(as_float(0x39800000)))) {
if (unlikely(abstop12(y) < abstop12(as_float(0x800000))))
// 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 = as_uint32_bits(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);
}
return invalid(y);
}
} // namespace __llvm_libc