flang/unittests/Evaluate/fp-testing.cpp

   1 #include "fp-testing.h"
   2 #include "llvm/Support/Errno.h"
   3 #include <cstdio>
   4 #include <cstdlib>
   5 #include <cstring>
   6 #if __x86_64__
   7 #include <xmmintrin.h>
   8 #endif
   9
  10 using Fortran::common::RoundingMode;
  11 using Fortran::evaluate::RealFlag;
  12
  13 ScopedHostFloatingPointEnvironment::ScopedHostFloatingPointEnvironment(
  14 #if __x86_64__
  15     bool treatSubnormalOperandsAsZero, bool flushSubnormalResultsToZero
  16 #else
  17     bool, bool
  18 #endif
  19 ) {
  20   errno = 0;
  21   if (feholdexcept(&originalFenv_) != 0) {
  22     std::fprintf(stderr, "feholdexcept() failed: %s\n",
  23         llvm::sys::StrError(errno).c_str());
  24     std::abort();
  25   }
  26   fenv_t currentFenv;
  27   if (fegetenv(&currentFenv) != 0) {
  28     std::fprintf(
  29         stderr, "fegetenv() failed: %s\n", llvm::sys::StrError(errno).c_str());
  30     std::abort();
  31   }
  32
  33 #if __x86_64__
  34   originalMxcsr = _mm_getcsr();
  35   unsigned int currentMxcsr{originalMxcsr};
  36   if (treatSubnormalOperandsAsZero) {
  37     currentMxcsr |= 0x0040;
  38   } else {
  39     currentMxcsr &= ~0x0040;
  40   }
  41   if (flushSubnormalResultsToZero) {
  42     currentMxcsr |= 0x8000;
  43   } else {
  44     currentMxcsr &= ~0x8000;
  45   }
  46 #else
  47   // TODO others
  48 #endif
  49   errno = 0;
  50   if (fesetenv(&currentFenv) != 0) {
  51     std::fprintf(
  52         stderr, "fesetenv() failed: %s\n", llvm::sys::StrError(errno).c_str());
  53     std::abort();
  54   }
  55 #if __x86_64__
  56   _mm_setcsr(currentMxcsr);
  57 #endif
  58 }
  59
  60 ScopedHostFloatingPointEnvironment::~ScopedHostFloatingPointEnvironment() {
  61   errno = 0;
  62   if (fesetenv(&originalFenv_) != 0) {
  63     std::fprintf(
  64         stderr, "fesetenv() failed: %s\n", llvm::sys::StrError(errno).c_str());
  65     std::abort();
  66   }
  67 #if __x86_64__
  68   _mm_setcsr(originalMxcsr);
  69 #endif
  70 }
  71
  72 void ScopedHostFloatingPointEnvironment::ClearFlags() const {
  73   feclearexcept(FE_ALL_EXCEPT);
  74 }
  75
  76 RealFlags ScopedHostFloatingPointEnvironment::CurrentFlags() {
  77   int exceptions = fetestexcept(FE_ALL_EXCEPT);
  78   RealFlags flags;
  79   if (exceptions & FE_INVALID) {
  80     flags.set(RealFlag::InvalidArgument);
  81   }
  82   if (exceptions & FE_DIVBYZERO) {
  83     flags.set(RealFlag::DivideByZero);
  84   }
  85   if (exceptions & FE_OVERFLOW) {
  86     flags.set(RealFlag::Overflow);
  87   }
  88   if (exceptions & FE_UNDERFLOW) {
  89     flags.set(RealFlag::Underflow);
  90   }
  91   if (exceptions & FE_INEXACT) {
  92     flags.set(RealFlag::Inexact);
  93   }
  94   return flags;
  95 }
  96
  97 void ScopedHostFloatingPointEnvironment::SetRounding(Rounding rounding) {
  98   switch (rounding.mode) {
  99   case RoundingMode::TiesToEven:
 100     fesetround(FE_TONEAREST);
 101     break;
 102   case RoundingMode::ToZero:
 103     fesetround(FE_TOWARDZERO);
 104     break;
 105   case RoundingMode::Up:
 106     fesetround(FE_UPWARD);
 107     break;
 108   case RoundingMode::Down:
 109     fesetround(FE_DOWNWARD);
 110     break;
 111   case RoundingMode::TiesAwayFromZero:
 112     std::fprintf(stderr, "SetRounding: TiesAwayFromZero not available");
 113     std::abort();
 114     break;
 115   }
 116 }