core/fpu_ctrl.cpp

   1
   2 #include "config.h"
   3
   4 #include "fpu_ctrl.h"
   5
   6 #ifdef HAVE_INTRIN_H
   7 #include <intrin.h>
   8 #endif
   9 #ifdef HAVE_SSE_INTRINSICS
  10 #include <emmintrin.h>
  11 #elif defined(HAVE_SSE)
  12 #include <xmmintrin.h>
  13 #endif
  14
  15 #if defined(HAVE_SSE) && !defined(_MM_DENORMALS_ZERO_MASK)
  16 /* Some headers seem to be missing these? */
  17 #define _MM_DENORMALS_ZERO_MASK 0x0040u
  18 #define _MM_DENORMALS_ZERO_ON 0x0040u
  19 #endif
  20
  21 #include "cpu_caps.h"
  22
  23 namespace {
  24
  25 #if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
  26 [[gnu::target("sse")]]
  27 #endif
  28 [[maybe_unused]]
  29 void disable_denormals(unsigned int *state [[maybe_unused]])
  30 {
  31 #if defined(HAVE_SSE_INTRINSICS)
  32     *state = _mm_getcsr();
  33     unsigned int sseState{*state};
  34     sseState &= ~(_MM_FLUSH_ZERO_MASK | _MM_DENORMALS_ZERO_MASK);
  35     sseState |= _MM_FLUSH_ZERO_ON | _MM_DENORMALS_ZERO_ON;
  36     _mm_setcsr(sseState);
  37
  38 #elif defined(HAVE_SSE)
  39
  40     *state = _mm_getcsr();
  41     unsigned int sseState{*state};
  42     sseState &= ~_MM_FLUSH_ZERO_MASK;
  43     sseState |= _MM_FLUSH_ZERO_ON;
  44     if((CPUCapFlags&CPU_CAP_SSE2))
  45     {
  46         sseState &= ~_MM_DENORMALS_ZERO_MASK;
  47         sseState |= _MM_DENORMALS_ZERO_ON;
  48     }
  49     _mm_setcsr(sseState);
  50 #endif
  51 }
  52
  53 #if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
  54 [[gnu::target("sse")]]
  55 #endif
  56 [[maybe_unused]]
  57 void reset_fpu(unsigned int state [[maybe_unused]])
  58 {
  59 #if defined(HAVE_SSE_INTRINSICS) || defined(HAVE_SSE)
  60     _mm_setcsr(state);
  61 #endif
  62 }
  63
  64 } // namespace
  65
  66
  67 unsigned int FPUCtl::Set() noexcept
  68 {
  69     unsigned int state{};
  70 #if defined(HAVE_SSE_INTRINSICS)
  71     disable_denormals(&state);
  72 #elif defined(HAVE_SSE)
  73     if((CPUCapFlags&CPU_CAP_SSE))
  74         disable_denormals(&state);
  75 #endif
  76     return state;
  77 }
  78
  79 void FPUCtl::Reset(unsigned int state [[maybe_unused]]) noexcept
  80 {
  81 #if defined(HAVE_SSE_INTRINSICS)
  82     reset_fpu(state);
  83 #elif defined(HAVE_SSE)
  84     if((CPUCapFlags&CPU_CAP_SSE))
  85         reset_fpu(state);
  86 #endif
  87 }