[PATCH] D49310: [llvm-mca][BtVer2] Teach how to identify dependency-breaking idioms.

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri added inline comments.


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Comment at: tools/llvm-mca/DispatchStage.cpp:110
   // An example of dependency-breaking instruction on X86 is a zero-idiom XOR.
-  if (!Desc.isZeroLatency())
-    for (std::unique_ptr<ReadState> &RS : IS.getUses())
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andreadb wrote:
> lebedev.ri wrote:
> > So it will no longer even consider the sched profile?
> Not sure I understand the question. I am definitely using profile information from the scheduling model.
What i'm asking is - what happens if sched model says that instruction N has zero latency, but `isDependencyBreaking()` does not say that?


https://reviews.llvm.org/D49310