[GVN][NewGVN][Local] Handle attributes for function calls after CSE (#114011)

This patch intersects attributes of two calls to avoid introducing UB.
It also skips incompatible call pairs in GVN/NewGVN. However, I cannot
provide negative tests for these changes.

Fixes https://github.com/llvm/llvm-project/issues/113997.

1 files changed, 11 insertions, 0 deletions

diff --git a/llvm/lib/Transforms/Utils/Local.cpp b/llvm/lib/Transforms/Utils/Local.cpp
index 65c1669f..47a7049 100644
--- a/llvm/lib/Transforms/Utils/Local.cpp
+++ b/llvm/lib/Transforms/Utils/Local.cpp
@@ -3508,6 +3508,17 @@ void llvm::patchReplacementInstruction(Instruction *I, Value *Repl) {
   else if (!isa<LoadInst>(I))
     ReplInst->andIRFlags(I);
 
+  // Handle attributes.
+  if (auto *CB1 = dyn_cast<CallBase>(ReplInst)) {
+    if (auto *CB2 = dyn_cast<CallBase>(I)) {
+      bool Success = CB1->tryIntersectAttributes(CB2);
+      assert(Success && "We should not be trying to sink callbases "
+                        "with non-intersectable attributes");
+      // For NDEBUG Compile.
+      (void)Success;
+    }
+  }
+
   // FIXME: If both the original and replacement value are part of the
   // same control-flow region (meaning that the execution of one
   // guarantees the execution of the other), then we can combine the