[Bug rtl-optimization/55583] Extended shift instruction on x86-64 is not used, producing unoptimal code

hjl.tools at gmail dot com gcc-bugzilla@gcc.gnu.org
Tue Dec 4 00:21:00 GMT 2012


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55583

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2012-12-04
                 CC|                            |areg.melikadamyan at gmail
                   |                            |dot com, hjl.tools at gmail
                   |                            |dot com, ubizjak at gmail
                   |                            |dot com
     Ever Confirmed|0                           |1

--- Comment #2 from H.J. Lu <hjl.tools at gmail dot com> 2012-12-04 00:21:02 UTC ---
Clang generates:

    movl    a(%rip), %eax
    shldl    $2, %eax, b(%rip)
    ret

at -O2.



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