src/cpu/x86/vm/vm_version_x86.cpp

*** 1289,1319 ****
      // Modern processors allow misaligned memory operations for vectors.
      AlignVector = !UseUnalignedLoadStores;
    }
  #endif // COMPILER2
  
!   if( AllocatePrefetchInstr == 3 && !supports_3dnow_prefetch() ) AllocatePrefetchInstr=0;
!   if( !supports_sse() && supports_3dnow_prefetch() ) AllocatePrefetchInstr = 3;
  
    // Allocation prefetch settings
    intx cache_line_size = prefetch_data_size();
!   if( cache_line_size > AllocatePrefetchStepSize )
!     AllocatePrefetchStepSize = cache_line_size;
  
    AllocatePrefetchDistance = allocate_prefetch_distance();
    AllocatePrefetchStyle    = allocate_prefetch_style();
  
    if (is_intel() && cpu_family() == 6 && supports_sse3()) {
!     if (AllocatePrefetchStyle == 2) { // watermark prefetching on Core
  #ifdef _LP64
!       AllocatePrefetchDistance = 384;
  #else
!       AllocatePrefetchDistance = 320;
  #endif
      }
      if (supports_sse4_2() && supports_ht()) { // Nehalem based cpus
!       AllocatePrefetchDistance = 192;
        if (FLAG_IS_DEFAULT(AllocatePrefetchLines)) {
          FLAG_SET_DEFAULT(AllocatePrefetchLines, 4);
        }
      }
  #ifdef COMPILER2
--- 1289,1329 ----
      // Modern processors allow misaligned memory operations for vectors.
      AlignVector = !UseUnalignedLoadStores;
    }
  #endif // COMPILER2
  
!   if (FLAG_IS_DEFAULT(AllocatePrefetchInstr)) {
!     if (AllocatePrefetchInstr == 3 && !supports_3dnow_prefetch()) {
!       FLAG_SET_DEFAULT(AllocatePrefetchInstr, 0);
!     } else if (!supports_sse() && supports_3dnow_prefetch()) {
!       FLAG_SET_DEFAULT(AllocatePrefetchInstr, 3);
!     }
!   }
  
    // Allocation prefetch settings
    intx cache_line_size = prefetch_data_size();
!   if (FLAG_IS_DEFAULT(AllocatePrefetchDistance) &&
!       (cache_line_size > AllocatePrefetchStepSize)) {
!     FLAG_SET_DEFAULT(AllocatePrefetchStepSize, cache_line_size);
!   }
  
    AllocatePrefetchDistance = allocate_prefetch_distance();
    AllocatePrefetchStyle    = allocate_prefetch_style();
  
    if (is_intel() && cpu_family() == 6 && supports_sse3()) {
!     if (FLAG_IS_DEFAULT(AllocatePrefetchDistance) &&
!         (AllocatePrefetchStyle == 2)) { // watermark prefetching on Core
  #ifdef _LP64
!       FLAG_SET_DEFAULT(AllocatePrefetchDistance, 384);
  #else
!       FLAG_SET_DEFAULT(AllocatePrefetchDistance, 320);
  #endif
      }
      if (supports_sse4_2() && supports_ht()) { // Nehalem based cpus
!       if (FLAG_IS_DEFAULT(AllocatePrefetchDistance)) {
!         FLAG_SET_DEFAULT(AllocatePrefetchDistance, 192);
!       }
        if (FLAG_IS_DEFAULT(AllocatePrefetchLines)) {
          FLAG_SET_DEFAULT(AllocatePrefetchLines, 4);
        }
      }
  #ifdef COMPILER2