| //===-- Implementation of the tan function for x86_64 ---------------------===// |
| // |
| // 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 "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 |
