Fwd: [PATCH] Scheduling result adjustment to enable macro-fusion

Andi Kleen andi@firstfloor.org
Sat Sep 14 06:10:00 GMT 2013


Wei Mi <wmi@google.com> writes:

>> Checking corei7/corei7-avx explicitly isn't a good idea.
>> It is also useful for Ivy Bridge and Haswell.  I think you
>> should use a variable to control it, similar to
>> TARGET_FUSE_CMP_AND_BRANCH.
>>
>>
>> --
>> H.J.
>
> Different x86 microarchitectures support macro-fusion for different
> compare and branch combinations. I need to differentiate various x86
> microarchitectures. If use TARGET_FUSE_CMP_AND_BRANCH like vars to
> control it, it requires a bunch of them. That is why I choose to check
> corei7/corei7-avx in that function. I don't add core-avx-i/core-avx2
> for now because I don't have those machines for testing.

They are normally a super set of each other.
So flags as suggested by HJ will work better than explicit matches.

-Andi



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