[compiler-rt] [llvm] [msan] Add experimental '-mllvm -msan-embed-faulting-instruction' and MSAN_OPTIONS=print_faulting_instruction (PR #136539)

[Florian Mayer via llvm-commits]

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@@ -1455,21 +1513,51 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
     // correct origin.
     bool Combine = !MS.TrackOrigins;
     Instruction *Instruction = InstructionChecks.front().OrigIns;
+
+    Value *InstName = nullptr;
+    if (ClEmbedFaultingInst >= 1) {
+      IRBuilder<> IRB0(Instruction);
+      std::string str;
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fmayer wrote:

I think this is only used in one branch?

https://github.com/llvm/llvm-project/pull/136539