[Bug middle-end/47581] [4.5/4.6 regression] Unnecessary adjustments to stack pointer

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47581

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
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                 CC|                            |matz at gcc dot gnu.org

--- Comment #9 from H.J. Lu <hjl.tools at gmail dot com> 2011-02-02 15:05:10 UTC ---
(In reply to comment #8)
> For this tescase, gcc 4.4 generates the most efficient code
> while 4.5/4.6 become worse and worse:
> 
> [hjl@gnu-6 gcc]$ cat x.i 
> unsigned mulh(unsigned a, unsigned b)
> {
>   unsigned long long l __attribute__ ((aligned(32)))
>     =((unsigned long long)a * (unsigned long long)b) >> 32;
>   return l;
> }

This is caused by revision 146817:

http://gcc.gnu.org/ml/gcc-cvs/2009-04/msg01459.html