[PATCH] D136523: [MSAN] Add handleCountZeroes for vector versions of ctlz and cttz.

[Evgenii Stepanov via Phabricator via llvm-commits]

eugenis added inline comments.


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Comment at: llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp:2974
+  void handleCountZeroes(IntrinsicInst &I) {
+    // if not vector operation, then just use default
+    Type::TypeID InputTypeID = I.getArgOperand(0)->getType()->getTypeID();
----------------
isn't this implementation strictly better than default? It handles the second operand correctly.


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Comment at: llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp:2976
+    Type::TypeID InputTypeID = I.getArgOperand(0)->getType()->getTypeID();
+    if (InputTypeID != Type::FixedVectorTyID) {
+      if (!handleUnknownIntrinsic(I))
----------------
Is there a problem with scalable vectors? You could just use Type::isVectorTy() otherwise.


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Comment at: llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp:2994
+    if (!constOperand->isZeroValue()) {
+      BoolZeroPoison = IRB.CreateICmpEQ(
+          Operand, Constant::getNullValue(Operand->getType()), "_mscz_bzp");
----------------
use CreateIsNull


Repository:
  rG LLVM Github Monorepo

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https://reviews.llvm.org/D136523