[PATCH] D37507: Fix maximum legal VF calculation

[Ayal Zaks via Phabricator via llvm-commits]

Ayal accepted this revision.
Ayal added inline comments.
This revision is now accepted and ready to land.


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Comment at: lib/Transforms/Vectorize/LoopVectorize.cpp:1562
+  uint64_t getMaxSafeRegisterWidth() const {
+	  return LAI->getDepChecker().getMaxSafeRegisterWidth();
+  }
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Best assert that LAI is not null before dereferencing it.


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Comment at: lib/Transforms/Vectorize/LoopVectorize.cpp:6222
+      ((WidestRegister < MaxSafeRegisterWidth) ? WidestRegister
+                                               : MaxSafeRegisterWidth);
   unsigned MaxVectorSize = WidestRegister / WidestType;
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While you're touching this, best use std::min.


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Comment at: test/Transforms/LoopVectorize/memdep.ll:230
+;Therefore the maxVF was computed as 8 instead of 4.  
+
+;#define M 32
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Better clarify:
; where the dependence distance here is 6 iterations, given by |N-(N-12)|/2.


https://reviews.llvm.org/D37507