libc/test/UnitTest/RoundingModeUtils.cpp

   1 //===-- RoundingModeUtils.cpp ---------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "RoundingModeUtils.h"
  10 #include "src/__support/FPUtil/FEnvImpl.h"
  11 #include "src/__support/FPUtil/rounding_mode.h"
  12
  13 #include <fenv.h>
  14
  15 namespace LIBC_NAMESPACE {
  16 namespace fputil {
  17 namespace testing {
  18
  19 int get_fe_rounding(RoundingMode mode) {
  20   switch (mode) {
  21   case RoundingMode::Upward:
  22     return FE_UPWARD;
  23   case RoundingMode::Downward:
  24     return FE_DOWNWARD;
  25   case RoundingMode::TowardZero:
  26     return FE_TOWARDZERO;
  27   case RoundingMode::Nearest:
  28     return FE_TONEAREST;
  29   }
  30   __builtin_unreachable();
  31 }
  32
  33 ForceRoundingMode::ForceRoundingMode(RoundingMode mode) {
  34   old_rounding_mode = quick_get_round();
  35   rounding_mode = get_fe_rounding(mode);
  36   if (old_rounding_mode != rounding_mode) {
  37     int status = set_round(rounding_mode);
  38     success = (status == 0);
  39   } else {
  40     success = true;
  41   }
  42 }
  43
  44 ForceRoundingMode::~ForceRoundingMode() {
  45   if (old_rounding_mode != rounding_mode)
  46     set_round(old_rounding_mode);
  47 }
  48
  49 } // namespace testing
  50 } // namespace fputil
  51 } // namespace LIBC_NAMESPACE