On Wed, Sep 12, 2012 at 8:30 PM, H.J. Lu <hjl.to...@gmail.com> wrote:
>> Newer AMD processors does not enable 3dNOW anymore. However, prefetchw
>> depends on TARGET_3DNOW, so it is not generated anymore. Following
>> patch is a 4.7 version of mainline patch [1].
>>
>> 2012-09-12 Uros Bizjak <ubiz...@gmail.com>
>>
>> * config/i386/i386.h (x86_prefetchw): New global variable.
>> (TARGET_PREFETCHW): New macro.
>> * config/i386/i386.c (PTA_PREFETCHW): Ditto.
>> (processor_alias_table): Add PTA_PREFETCHW to
>> bdver1, bdver2 and btver1.
>> (ix86_option_override_internal): Set x86_prefetchw for
>> PTA_PREFETCHW targets.
>> * config/i386/i386.md (prefetch): Expand to prefetchw
>> for TARGET_PREFETCHW.
>> (*prefetch_3dnow_<mode>): Also enable for TARGET_PREFETCHW.
>>
>> Patch was bootstrapped and regression tested on x86_64-pc-linux-gnu
>> {,-m32}. Will be committed to 4.7 branch after [1] is committed to
>> mainline.
>>
>> [1] http://gcc.gnu.org/ml/gcc-patches/2012-09/msg00670.html
>
> Do we need to update driver-i386.c?
No, the patch is not a backport of -mprfchw, but statically enables
prefetchw for targets that have prefetchw, but don't define
TARGET_3DNOW anymore.
Uros.
