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Re: [PATCH, x86] Use vector moves in memmove expanding


On Tue, Sep 3, 2013 at 12:01 PM, Eric Botcazou <ebotcazou@adacore.com> wrote:
>> Changes were checked into trunk:
>> http://gcc.gnu.org/ml/gcc-cvs/2013-07/msg00179.html
>
> The patch miscompiles the MPFR library on x86 Pentium Pro.  Reduced testcase
> attached, compile for x86 with -mtune=pentiumpro.
>

The change in question has

@@ -23169,7 +23150,7 @@ ix86_expand_movmem (rtx dst, rtx src, rtx
count_exp, rtx align_exp,

   if (count_exp != const0_rtx && epilogue_size_needed > 1)
     expand_movmem_epilogue (dst, src, destreg, srcreg, count_exp,
-                           epilogue_size_needed);
+                           size_needed);
   if (jump_around_label)
     emit_label (jump_around_label);
   return true;

Michael, why did you change epilogue_size_needed to size_needed
here?  It looks wrong to me.

-- 
H.J.


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