[PATCH] D50465: [InstCombine] Optimize redundant 'signed truncation check pattern'.

[Sanjay Patel via Phabricator via llvm-commits]

spatel added inline comments.


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Comment at: lib/Transforms/InstCombine/InstCombineAndOrXor.cpp:1307-1308
 
+// See detailed explaination of the pattern in
+// test/Transforms/InstCombine/signed-truncation-check.ll
+static Value *foldSignedTruncationCheck(BinaryOperator &I,
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It's better to include the comment from the test file directly (or at least a shorter description) instead of asking the reader to jump to another file for documentation.


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Comment at: lib/Transforms/InstCombine/InstCombineAndOrXor.cpp:1311-1316
+  assert(I.getOpcode() == Instruction::And);
+  // We are looking for an 'and' of two icmp's
+  auto *ICmp0 = dyn_cast<ICmpInst>(I.getOperand(0));
+  auto *ICmp1 = dyn_cast<ICmpInst>(I.getOperand(1));
+  if (!(ICmp0 && ICmp1))
+    return nullptr;
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Can this be moved within InstCombiner::foldAndOfICmps() to eliminate these preliminary checks?

Any chance for shared functionality with foldAndOrOfICmpsOfAndWithPow2() or simplifyRangeCheck()?


Repository:
  rL LLVM

https://reviews.llvm.org/D50465