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Subject: [Bug target/39942] Nonoptimal code - leaveq; xchg   %ax,%ax; retq
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------- Comment #12 from vvv at ru dot ru  2009-04-29 07:55 -------
(In reply to comment #9)
> So that explains it, Use -Os or attribute cold if you want NOPs to be gone.

But my measurements on Core 2 Duo P8600 show that

push %ebp
mov  %esp,%ebp
leave
ret

_faster_ then

push %ebp
mov  %esp,%ebp
leave
xchg %ax,%ax
ret


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39942