[Bug rtl-optimization/50339] suboptimal register allocation for abs(__int128_t)

glisse at gcc dot gnu.org gcc-bugzilla@gcc.gnu.org
Fri Nov 2 14:34:00 GMT 2012


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50339

--- Comment #2 from Marc Glisse <glisse at gcc dot gnu.org> 2012-11-02 14:33:27 UTC ---
It looks even worse in 4.8:

    movq    %rdi, %r9
    movq    %rsi, %rdi
    movq    %rsi, %r10
    sarq    $63, %rdi
    movq    %rdi, %rcx
    xorq    %r9, %rcx
    movq    %rcx, %rax
    movq    %r10, %rcx
    xorq    %rdi, %rcx
    subq    %rdi, %rax
    movq    %rcx, %rdx
    sbbq    %rdi, %rdx
    ret



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