[Bug rtl-optimization/50107] [IRA, i386] allocates regiters in very non-optimal way

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50107

--- Comment #4 from H.J. Lu <hjl.tools at gmail dot com> 2011-08-17 19:16:40 
UTC ---
Created attachment 25038
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25038
A patch

This patch generates:

    movq    %rdi, %rdx
    mulx    %rsi, %r10, %r9
    addq    $3, %r9
    adcq    $0, %r10
    movq    %r9, k2(%rip)
    movq    %r9, %rax
    movq    %r10, k2+8(%rip)
    movq    %r10, %rdx
    ret