[clang] [compiler-rt] [llvm] [InstrFDO][TypeProf] Implement binary instrumentation and profile read/write (PR #66825)

[Snehasish Kumar via cfe-commits]

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@@ -16,23 +16,72 @@
 #include <vector>
 
 namespace llvm {
-// Visitor class that finds all indirect call.
+// Visitor class that finds indirect calls or instructions that gives vtable
+// value, depending on Type.
 struct PGOIndirectCallVisitor : public InstVisitor<PGOIndirectCallVisitor> {
+  enum class InstructionType {
+    kIndirectCall = 0,
+    kVTableVal = 1,
+  };
   std::vector<CallBase *> IndirectCalls;
-  PGOIndirectCallVisitor() = default;
+  std::vector<Instruction *> ProfiledAddresses;
+  PGOIndirectCallVisitor(InstructionType Type) : Type(Type) {}
 
   void visitCallBase(CallBase &Call) {
-    if (Call.isIndirectCall())
+    if (Call.isIndirectCall()) {
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snehasish wrote:

Can we flip this condition and return early to reduce the nesting?

https://github.com/llvm/llvm-project/pull/66825