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Viewing changes to src/threads/ATL_ResetAtomicCount_ia32.S

  • Committer: Package Import Robot
  • Author(s): Sébastien Villemot
  • Date: 2013-06-11 15:58:16 UTC
  • mfrom: (1.1.3 upstream)
  • mto: (2.2.21 experimental)
  • mto: This revision was merged to the branch mainline in revision 26.
  • Revision ID: package-import@ubuntu.com-20130611155816-b72z8f621tuhbzn0
Tags: upstream-3.10.1
Import upstream version 3.10.1

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src/threads/ATL_ResetAtomicCount_ia32.S
 
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#include "atlas_asm.h"
 
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/*
 
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 * rax                       rdi         rsi
 
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 * int ATL_ResetAtomicCount(void *vp, int cnt)
 
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 * Sets vp's acnt=cnt.
 
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 * RETURNS: acnt before the reset
 
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 */
 
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.text
 
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.global ATL_asmdecor(ATL_ResetAtomicCount)
 
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ATL_asmdecor(ATL_ResetAtomicCount):
 
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   movl 4(%esp), %edx
 
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   movl 8(%esp), %ecx
 
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   sub $-128, %edx            /* skip false sharing guard zone */
 
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   ATOMIC_LOOP:
 
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      movl (%edx), %eax       /* read acnt from memory */
 
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      lock                    /* make cmpxchg atomic */
 
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      cmpxchg %ecx, (%edx)   /* put cnt in mem if mem still == acnt in eax */
 
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      je DONE                 /* ZF set if cmpxchg wrote to mem */
 
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   jmp ATOMIC_LOOP            /* ZF=0 means cmpxch failed, try again */
 
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DONE:
 
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   ret