[PATCH] D70009: [ARM][ReachingDefAnalysis] Use RDA for loloops

[Sam Parker via Phabricator via llvm-commits]

samparker marked an inline comment as done.
samparker added inline comments.


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Comment at: llvm/lib/Target/ARM/ARMLowOverheadLoops.cpp:358
+  if (SetFlags) {
+    if (RDA->getReachingDef(&MBB->back(), ARM::CPSR) > RDA->getInstId(MI))
+      SetFlags = false;
----------------
dmgreen wrote:
> samparker wrote:
> > dmgreen wrote:
> > > Does this change need the Defs = [CPSR] for t2LoopDec change? Are there some tests for these cases that didn't change?
> > It didn't need it in the end as this logic allows us to query for a CPSR def inbetween LoopDec (MI) and LoopEnd (back). Again, I'll create a helper which allows us to clearly whether we have a def of something inbetween A and B.
> And we don't need to check for uses any more?
Argh! Indeed we do. And that means there's a hole in my testing.


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https://reviews.llvm.org/D70009