blob: 9146473741f9575767172784e2d4d7a2874b4674 [file] [log] [blame]
//===-- Implementation of the tan function for x86_64 ---------------------===//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "src/math/tan.h"
#include "src/__support/common.h"
namespace __llvm_libc {
LLVM_LIBC_FUNCTION(double, tan, (double x)) {
double result;
double one;
// The fptan instruction pushes the number 1 on to the FP stack after
// computing tan. So, we read out the one before popping the actual result.
__asm__ __volatile__("fptan" : "=t"(one) : "f"(x));
__asm__ __volatile__("fstpl %0" : "=m"(result));
return result;
} // namespace __llvm_libc