[PATCH] D26420: Encode duplication factor from loop vectorization and loop unrolling to discriminator.

[Hal Finkel via Phabricator via llvm-commits]

hfinkel added inline comments.


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Comment at: include/llvm/IR/DebugInfoMetadata.h:1684
+
+/*
+ unsigned D = getDiscriminator();
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Please move the comments that explain the encoding to above `DILocation::getBaseDiscriminator` and write some text to explain what is going on.


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Comment at: lib/Transforms/Utils/AddDiscriminators.cpp:197
       // it in 1 byte ULEB128 representation.
-      unsigned Discriminator = (R.second ? ++LDM[L] : LDM[L]) & 0x7f;
+      unsigned Discriminator = ((R.second ? ++LDM[L] : LDM[L]) << 1) & 0x7f;
       I.setDebugLoc(DIL->cloneWithDiscriminator(Discriminator));
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Please add a utility function for the encoding.


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Comment at: lib/Transforms/Vectorize/LoopVectorize.cpp:216
 
+extern cl::opt<bool> EncodeDuplicationInDiscriminators;
+
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Based on one of the other threads, I suppose we're going to add some command-line flag to enable/disable this? That being the case, we'll read this setting from some function attribute string instead of using  a cl::opt.


https://reviews.llvm.org/D26420