[llvm] [msan] Don't modify CFG iterating it (PR #90691)

[Florian Mayer via llvm-commits]

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@@ -2181,6 +2187,10 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
     return ConstantDataVector::get(IRB.getContext(), OrderingTable);
   }
 
+  void instrument(Instruction &I) {
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fmayer wrote:

Why don't we just call `InstVisitor<MemorySanitizerVisitor>::visit` in the loop?

https://github.com/llvm/llvm-project/pull/90691