[PATCH] D33262: [JumpThreading] Teach jump threading how to analyze (and (cmp A, C1), (cmp A, C2)) after InstCombine has turned it into (cmp (add A, C3), C4)

[Chandler Carruth via Phabricator via llvm-commits]

chandlerc added a comment.

Sorry for the drive by review, but I noticed one cleanup below and I have to ask: why is there no test case here? That seems kinda bad. I feel like there should be tests for folding to true, folding to false, and some negative testing that things which *shouldn't* be threaded here aren't....



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Comment at: llvm/trunk/lib/Transforms/Scalar/JumpThreading.cpp:647-649
+            match(CmpLHS, m_Add(m_Value(AddLHS), m_ConstantInt(AddConst)))) {
+          if (!isa<Instruction>(AddLHS) ||
+              cast<Instruction>(AddLHS)->getParent() != BB) {
----------------
You can remove all of the `isa<Instruction>` and `cast<Intsruction>` dance by using `m_Instruction` in the pattern match and making `AddLHS` an `Instruction*`.


Repository:
  rL LLVM

https://reviews.llvm.org/D33262