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[Bug c++/37922] [4.4 Regression] code generation error



------- Comment #13 from jakub at gcc dot gnu dot org  2008-12-16 15:05 -------
Not doing this optimization if added_clobbers_hard_reg_p would basically kill
it on i386/x86_64 except for constant values, all the shifts clobber hard
registers.  But typically flags register is only live for very short range
between compare and (usually the next insn) following conditional jump.  Given
how many insns clobber the flags it is very rare to have the setter and user
many insns appart.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37922


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