[PATCH] D35499: [InstCombine] Simplify pointer difference subtractions (GEP-GEP) where GEPs have other uses and one non-constant index

[Sanjoy Das via Phabricator via llvm-commits]

sanjoy accepted this revision.
sanjoy added a comment.
This revision is now accepted and ready to land.

lgtm with minor nits



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Comment at: include/llvm/IR/Operator.h:475
 
+  unsigned getNumNonConstantIndices() const {
+    unsigned NumNonConstantIndices = 0;
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I'd call this `countNonConstantIndices`.


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Comment at: include/llvm/IR/Operator.h:477
+    unsigned NumNonConstantIndices = 0;
+    for (const_op_iterator I = idx_begin(), E = idx_end(); I != E; ++I) {
+      if (!isa<ConstantInt>(I)) {
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You can use `llvm::count_if` here.


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Comment at: lib/Transforms/InstCombine/InstCombineAddSub.cpp:1490
+         (NumNonConstantIndices2 > 0 && !GEP2->hasOneUse()))) {
+      DEBUG(dbgs() << "Rejected because ...\n");
+      return nullptr;
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Please add a full sentence here, or remove it.


https://reviews.llvm.org/D35499