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Re: PATCH: PR target/39942: Nonoptimal code - leaveq; xchg %ax,%ax; retq
On Mon, May 18, 2009 at 8:59 AM, Uros Bizjak <ubizjak@gmail.com> wrote:
> H.J. Lu wrote:
>
>>>> ix86_avoid_jump_misspredicts use "align" pattern to pad to a 16byte
>>>> boundary. "align" pattern uses ASM_OUTPUT_MAX_SKIP_ALIGN. For Linux,
>>>> it
>>>>
>>>
>>> See my http://gcc.gnu.org/ml/gcc-patches/2009-05/msg00702.html
>>> patch, I think ASM_OUTPUT_MAX_SKIP_ALIGN should be fixed anyway
>>> to not do the extra .p2align 3 if MAX_SKIP is less than 7.
>>> ASM_OUTPUT_MAX_SKIP_PAD doesn't hurt, though I think it only rarely
>>> will make a difference. ïAnyway, I think it makes no sense to require
>>> it duplicated in all the headers, just define the new macro
>>> in linux.h and x86-64.h and in i386.md just use ASM_OUTPUT_MAX_SKIP_PAD
>>> if it exists, otherwise fall back to ASM_OUTPUT_MAX_SKIP_ALIGN.
>>>
>>>
>>
>> Here is the updated patch. ÂOK for trunk?
>>
>
>> 2009-05-15 ÂH.J. Lu Â<hongjiu.lu@intel.com>
>>
>> Â Â Â ÂPR target/39942
>> Â Â Â Â* config/i386/i386.c (ix86_avoid_jump_misspredicts): Replace
>> Â Â Â Âgen_align with gen_pad.
>>
>> Â Â Â Â* config/i386/i386.md (align): Renamed to ...
>> Â Â Â Â(pad): This. ÂReplace ASM_OUTPUT_MAX_SKIP_ALIGN with
>> Â Â Â ÂASM_OUTPUT_MAX_SKIP_PAD.
>>
>> Â Â Â Â* config/i386/i386.h (ASM_OUTPUT_MAX_SKIP_PAD): New.
>> Â Â Â Â* config/i386/x86-64.h (ASM_OUTPUT_MAX_SKIP_PAD): Likewise.
>>
>
> OK for mainline; see bellow for a small comment.
>
Jakub has checked in a different patch:
http://gcc.gnu.org/ml/gcc-patches/2009-05/msg00702.html
--
H.J.