alc/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 <xmmintrin.h>
  11 #endif
  12
  13 #include "cpu_caps.h"
  14
  15
  16 FPUCtl::FPUCtl()
  17 {
  18 #if defined(HAVE_SSE_INTRINSICS)
  19     this->sse_state = _mm_getcsr();
  20     unsigned int sseState = this->sse_state;
  21     sseState |= 0x8000; /* set flush-to-zero */
  22     sseState |= 0x0040; /* set denormals-are-zero */
  23     _mm_setcsr(sseState);
  24
  25 #elif defined(__GNUC__) && defined(HAVE_SSE)
  26
  27     if((CPUCapFlags&CPU_CAP_SSE))
  28     {
  29         __asm__ __volatile__("stmxcsr %0" : "=m" (*&this->sse_state));
  30         unsigned int sseState = this->sse_state;
  31         sseState |= 0x8000; /* set flush-to-zero */
  32         if((CPUCapFlags&CPU_CAP_SSE2))
  33             sseState |= 0x0040; /* set denormals-are-zero */
  34         __asm__ __volatile__("ldmxcsr %0" : : "m" (*&sseState));
  35     }
  36 #endif
  37
  38     this->in_mode = true;
  39 }
  40
  41 void FPUCtl::leave()
  42 {
  43     if(!this->in_mode) return;
  44
  45 #if defined(HAVE_SSE_INTRINSICS)
  46     _mm_setcsr(this->sse_state);
  47
  48 #elif defined(__GNUC__) && defined(HAVE_SSE)
  49
  50     if((CPUCapFlags&CPU_CAP_SSE))
  51         __asm__ __volatile__("ldmxcsr %0" : : "m" (*&this->sse_state));
  52 #endif
  53     this->in_mode = false;
  54 }