CallGraph: Fix IgnoreAssumeLikeCalls option to Function::hasAddressTaken

This was added in 29e2d9461a91b and likely never worked in a useful
way.

The test added for it fails when converted to opaque pointers, since
the lifetime intrinsic now directly uses the address. The code was
only trying to handle a user indirectly through a bitcast
instruction. That would never have been useful; a bitcast of a global
value would be folded to a ConstantExpr cast.

I also don't understand why it was special casing use_empty on the
cast. Relax the check to be either BitCastOperator or
AddrSpaceCastOperator. In practice, BitCastOperator won't appear
today.

I believe the change in parallel_deletion_cg_update is a correct
improvement but I didn't fully follow it. .omp_outlined..0 is used in
a constant expression cast to a call which ends up getting deleted.

1 files changed, 19 insertions, 10 deletions

diff --git a/llvm/lib/IR/Function.cpp b/llvm/lib/IR/Function.cpp
index 9912e1a..792e714 100644
--- a/llvm/lib/IR/Function.cpp
+++ b/llvm/lib/IR/Function.cpp
@@ -1876,6 +1876,10 @@ std::optional<Function *> Intrinsic::remangleIntrinsicFunction(Function *F) {
   return NewDecl;
 }
 
+static bool isPointerCastOperator(const User *U) {
+  return isa<AddrSpaceCastOperator>(U) || isa<BitCastOperator>(U);
+}
+
 /// hasAddressTaken - returns true if there are any uses of this function
 /// other than direct calls or invokes to it. Optionally ignores callback
 /// uses, assume like pointer annotation calls, and references in llvm.used
@@ -1897,17 +1901,15 @@ bool Function::hasAddressTaken(const User **PutOffender,
 
     const auto *Call = dyn_cast<CallBase>(FU);
     if (!Call) {
-      if (IgnoreAssumeLikeCalls) {
-        if (const auto *FI = dyn_cast<Instruction>(FU)) {
-          if (FI->isCast() && !FI->user_empty() &&
-              llvm::all_of(FU->users(), [](const User *U) {
-                if (const auto *I = dyn_cast<IntrinsicInst>(U))
-                  return I->isAssumeLikeIntrinsic();
-                return false;
-              }))
-            continue;
-        }
+      if (IgnoreAssumeLikeCalls && isPointerCastOperator(FU) &&
+          all_of(FU->users(), [](const User *U) {
+            if (const auto *I = dyn_cast<IntrinsicInst>(U))
+              return I->isAssumeLikeIntrinsic();
+            return false;
+          })) {
+        continue;
       }
+
       if (IgnoreLLVMUsed && !FU->user_empty()) {
         const User *FUU = FU;
         if (isa<BitCastOperator>(FU) && FU->hasOneUse() &&
@@ -1926,6 +1928,13 @@ bool Function::hasAddressTaken(const User **PutOffender,
         *PutOffender = FU;
       return true;
     }
+
+    if (IgnoreAssumeLikeCalls) {
+      if (const auto *I = dyn_cast<IntrinsicInst>(Call))
+        if (I->isAssumeLikeIntrinsic())
+          continue;
+    }
+
     if (!Call->isCallee(&U) || Call->getFunctionType() != getFunctionType()) {
       if (IgnoreARCAttachedCall &&
           Call->isOperandBundleOfType(LLVMContext::OB_clang_arc_attachedcall,