reactos/lib/rtl/i386/prefetchmemory_asm.s

   1 /*
   2  * COPYRIGHT:       See COPYING in the top level directory
   3  * PROJECT:         ReactOS kernel
   4  * FILE:            prefetchmemory_asm.S
   5  * PURPOSE:         Memory functions
   6  * PROGRAMMERS:     Patrick Baggett (baggett.patrick@gmail.com)
   7  *                  Alex Ionescu (alex@relsoft.net)
   8  *                  Magnus Olsen (magnusolsen@greatlord.com)
   9  */
  10
  11 .intel_syntax noprefix
  12
  13 /* GLOBALS ****************************************************************/
  14
  15 .globl  @RtlPrefetchMemoryNonTemporal@8
  16
  17 /* FUNCTIONS ***************************************************************/
  18
  19 @RtlPrefetchMemoryNonTemporal@8:
  20         ret         /* Overwritten by ntoskrnl/ke/i386/kernel.c if SSE is supported (see Ki386SetProcessorFeatures() ) */
  21
  22         mov eax, [_Ke386CacheAlignment]    // Get cache line size
  23
  24         // This is fastcall, so ecx = address, edx = size
  25 fetch_next_line:
  26         prefetchnta byte ptr [ecx]  // prefechnta(address)
  27         add ecx, eax                // address = address + cache_line_size
  28         sub edx, eax                // count = count - cache_line_size
  29         ja fetch_next_line          //     goto fetch_next_line
  30         ret