[Bug rtl-optimization/47521] Unnecessary usage of edx register

[tony.poppleton at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47521



--- Comment #7 from Tony Poppleton <tony.poppleton at gmail dot com> 2013-04-10 
01:51:36 UTC ---

This appears to be fixed with GCC 4.8.0 and flag -O2.  The asm code produced is

now exactly as Jeff said in comment #3:



        .file   "test.c"

        .text

        .p2align 4,,15

        .globl  foo

        .type   foo, @function

foo:

.LFB0:

        .cfi_startproc

        testb   $16, %dil

        movl    $1, %eax

        cmovne  %edi, %eax

        ret

        .cfi_endproc

.LFE0:

        .size   foo, .-foo

        .ident  "GCC: (GNU) 4.8.0 20130316 (Red Hat 4.8.0-0.17)"

        .section        .note.GNU-stack,"",@progbits