[PATCH] D55678: [CVP] Use LVI to constant fold deopt operands

[Anna Thomas via Phabricator via llvm-commits]

anna added inline comments.


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Comment at: lib/Transforms/Scalar/CorrelatedValuePropagation.cpp:471
+  // single use rules in instcombine).  Since deopt uses tend to,
+  // idiomatically, appear along rare conditional paths, it's reasonable likely
+  // we may have a conditional fact with which LVI can fold.   
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Nit: reasonably.


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Comment at: lib/Transforms/Scalar/CorrelatedValuePropagation.cpp:485
+      // instruction as per the checked in test in test/CVP/deopt.ll
+      Constant *C = LVI->getConstant(V, CS.getParent());
+      if (!C) continue;
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>From the code, `getConstant` calls `getValueInBlock` which returns the value at the end of the BasicBlock. The BB passed in here is the callsite's parent. We want the value which is true at the beginning of the `CS.getParent()` right?


Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D55678/new/

https://reviews.llvm.org/D55678