[PATCH] D92629: [dfsan] Add empty APIs for field-level shadow

[Matt Morehouse via Phabricator via llvm-commits]

morehouse added inline comments.


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Comment at: llvm/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp:425
+  /// primitive types, values or zero constants.
+  Constant *getZeroShadow(Type *OrigTy);
+  /// Returns a zero constant with the shadow type of V's type.
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This function looks unused by anything except the other `getZeroShadow`.  Can we remove it?


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Comment at: llvm/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp:431
+  /// Returns the shadow type of OrigTy.
+  Type *getShadowTy(Type *OrigTy);
+  /// Returns the shadow type of of V's type.
----------------
Maybe we don't need this function either?


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Comment at: llvm/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp:1684
       unsigned Size =
-          getDataLayout().getTypeAllocSize(DFSF.DFS.PrimitiveShadowTy);
+          getDataLayout().getTypeAllocSize(DFSF.DFS.getShadowTy(RT));
       if (Size <= kRetvalTLSSize) {
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Is this equivalent to `getShadowTy(S)`?  If so, we can save a line of code by doing that instead.


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Comment at: llvm/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp:1957
 void DFSanVisitor::visitPHINode(PHINode &PN) {
-  PHINode *ShadowPN = PHINode::Create(DFSF.DFS.PrimitiveShadowTy,
-                                      PN.getNumIncomingValues(), "", &PN);
+  Type *ShadowTy = DFSF.DFS.getShadowTy(PN.getType());
+  PHINode *ShadowPN =
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Let's make use of the overloaded `getShadowTy` to do `getShadowTy(PN)` instead.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D92629/new/

https://reviews.llvm.org/D92629