[Bug rtl-optimization/47582] Combine chains of movl into movq

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47582

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

           What    |Removed                     |Added
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                 CC|                            |hjl.tools at gmail dot com

--- Comment #5 from H.J. Lu <hjl.tools at gmail dot com> ---
(In reply to Tony from comment #4)
> Retesting this with gcc 7.1.1 20170622 (Red Hat 7.1.1-3) shows that the
> mov's are still not being combined, even though dependency #23684 is marked
> as fixed:
> 
> The DM1 branch produces:

With -O3, I got

main:
.LFB0:
        .cfi_startproc
        movups  b(%rip), %xmm0
        xorl    %eax, %eax
        movups  %xmm0, a(%rip)
        movss   b+16(%rip), %xmm0
        movss   %xmm0, a+16(%rip)
        ret
        .cfi_endproc
.LFE0: