[Asan] Add "funclet" OpBundle to Asan calls, when needed by EH Personality

Previously, when ASan instrumentation introduced runtime calls into EH pads, the appropriate funclet token expected by WinEHPrepare were missing.
The BB is then seen as invalid and discard by WinEHPrepare, leading to invalid code that crashes.

Also fixed localescape test, switching its EH personality to match code without funclets.

This PR is based on the Phabricator patch https://reviews.llvm.org/D143108

Fixes #64990

Author: sylvain-audi

compiler-rt/test/asan/TestCases/Windows/issue64990.cpp

@@ -0,0 +1,18 @@
+// Repro for the issue #64990: Asan with Windows EH generates __asan_xxx runtime calls without required funclet tokens
+// RUN: %clang_cl_asan %Od %s -EHsc %Fe%t
+// RUN: not %run %t 2>&1 | FileCheck %s
+
+char buff1[6] = "hello";
+char buff2[6] = "hello";
+
+int main(int argc, char **argv) {
+  try {
+    throw 1;
+  } catch (...) {
+    // Make asan generate call to __asan_memcpy inside the EH pad.
+    __builtin_memcpy(buff1, buff2 + 3, 6);
+  }
+  return 0;
+}
+
+// CHECK: SUMMARY: AddressSanitizer: global-buffer-overflow {{.*}} in __asan_memcpy

llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp

@@ -43,6 +43,7 @@
 #include "llvm/IR/DebugInfoMetadata.h"
 #include "llvm/IR/DebugLoc.h"
 #include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/EHPersonalities.h"
 #include "llvm/IR/Function.h"
 #include "llvm/IR/GlobalAlias.h"
 #include "llvm/IR/GlobalValue.h"
@@ -643,21 +644,70 @@ static uint64_t GetCtorAndDtorPriority(Triple &TargetTriple) {
 
 namespace {
 /// Helper RAII class to post-process inserted asan runtime calls during a
-/// pass on a single Function. This is a no-op implementation, for a first NFC
-/// commit. Coming up: detect and add "funclet" opBundle to function calls that
-/// need them.
+/// pass on a single Function. Upon end of scope, detects and applies the
+/// required funclet OpBundle.
 class RuntimeCallInserter {
   Function *OwnerFn = nullptr;
+  bool TrackInsertedCalls = false;
+  SmallVector<CallInst *> InsertedCalls;
 
 public:
-  RuntimeCallInserter(Function &Fn) : OwnerFn(&Fn) {}
+  RuntimeCallInserter(Function &Fn) : OwnerFn(&Fn) {
+    if (Fn.hasPersonalityFn()) {
+      auto Personality = classifyEHPersonality(Fn.getPersonalityFn());
+      if (isScopedEHPersonality(Personality))
+        TrackInsertedCalls = true;
+    }
+  }
+
+  ~RuntimeCallInserter() {
+    if (InsertedCalls.empty())
+      return;
+    assert(TrackInsertedCalls && "Calls were wrongly tracked");
+
+    DenseMap<BasicBlock *, ColorVector> BlockColors = colorEHFunclets(*OwnerFn);
+    for (CallInst *CI : InsertedCalls) {
+      BasicBlock *BB = CI->getParent();
+      assert(BB && "Instruction doesn't belong to a BasicBlock");
+      assert(BB->getParent() == OwnerFn &&
+             "Instruction doesn't belong to the expected Function!");
+
+      ColorVector &Colors = BlockColors[BB];
+      // funclet opbundles are only valid in monochromatic BBs.
+      // Note that unreachable BBs are seen as colorless by colorEHFunclets()
+      // and will be DCE'ed later.
+      if (Colors.empty())
+        continue;
+      if (Colors.size() != 1) {
+        OwnerFn->getContext().emitError(
+            "Instruction's BasicBlock is not monochromatic");
+        continue;
+      }
+
+      BasicBlock *Color = Colors.front();
+      Instruction *EHPad = Color->getFirstNonPHI();
+
+      if (EHPad && EHPad->isEHPad()) {
+        // Replace CI with a clone with an added funclet OperandBundle
+        OperandBundleDef OB("funclet", EHPad);
+        auto *NewCall =
+            CallBase::addOperandBundle(CI, LLVMContext::OB_funclet, OB, CI);
+        NewCall->copyMetadata(*CI);
+        CI->replaceAllUsesWith(NewCall);
+        CI->eraseFromParent();
+      }
+    }
+  }
 
   CallInst *createRuntimeCall(IRBuilder<> &IRB, FunctionCallee Callee,
                               ArrayRef<Value *> Args = {},
                               const Twine &Name = "") {
     assert(IRB.GetInsertBlock()->getParent() == OwnerFn);
-    (void)OwnerFn;
-    return IRB.CreateCall(Callee, Args, Name, nullptr);
+
+    CallInst *Inst = IRB.CreateCall(Callee, Args, Name, nullptr);
+    if (TrackInsertedCalls)
+      InsertedCalls.push_back(Inst);
+    return Inst;
   }
 };
 

llvm/test/Instrumentation/AddressSanitizer/asan-funclet.ll

@@ -14,10 +14,10 @@ declare ptr @llvm.eh.recoverfp(ptr, ptr)
 declare ptr @llvm.localrecover(ptr, ptr, i32)
 declare void @llvm.localescape(...) #1
 
-declare i32 @_except_handler3(...)
+declare i32 @__gcc_personality_v0(...)
 declare void @may_throw(ptr %r)
 
-define i32 @main() sanitize_address personality ptr @_except_handler3 {
+define i32 @main() sanitize_address personality ptr @__gcc_personality_v0 {
 entry:
   %r = alloca i32, align 4
   %__exception_code = alloca i32, align 4