Fix non-void return typed non-callee uses

Author: arsenm

llvm/test/tools/llvm-reduce/reduce-values-to-return-nonvoid-noncallee-use.ll

@@ -0,0 +1,27 @@
+; Make sure we don't break on non-callee uses of funtions with a
+; non-void return type.
+
+; RUN: llvm-reduce --abort-on-invalid-reduction --delta-passes=values-to-return --test FileCheck --test-arg --check-prefix=INTERESTING --test-arg %s --test-arg --input-file %s -o %t
+; RUN: FileCheck --check-prefix=RESULT %s < %t
+
+; INTERESTING-LABEL: @interesting(
+; INTERESTING: %inttoptr = inttoptr i64
+
+; RESULT-LABEL: define ptr @interesting(i64 %arg) {
+; RESULT-NEXT: %inttoptr = inttoptr i64 %arg to ptr
+; RESULT-NEXT:  ret ptr %inttoptr
+define void @interesting(i64 %arg) {
+  %inttoptr = inttoptr i64 %arg to ptr
+  %load = load i32, ptr %inttoptr
+  ret void
+}
+
+declare i32 @func(ptr)
+
+; RESULT-LABEL: define i32 @caller() {
+; RESULT-NEXT: %call = call i32 @func(ptr @interesting)
+; RESULT-NEXT: ret i32 %call
+define void @caller() {
+  %call = call i32 @func(ptr @interesting)
+  ret void
+}

llvm/tools/llvm-reduce/deltas/ReduceValuesToReturn.cpp

@@ -102,7 +102,8 @@ static void rewriteFuncWithReturnType(Function &OldF,
   // Adjust the callsite uses to the new return type. We pre-filtered cases
   // where the original call type was incorrectly non-void.
   for (User *U : make_early_inc_range(OldF.users())) {
-    if (auto *CB = dyn_cast<CallBase>(U)) {
+    if (auto *CB = dyn_cast<CallBase>(U);
+        CB && CB->getCalledOperand() == &OldF) {
       if (CB->getType()->isVoidTy()) {
         FunctionType *CallType = CB->getFunctionType();
 
@@ -115,7 +116,7 @@ static void rewriteFuncWithReturnType(Function &OldF,
         CB->setCalledFunction(NewCallType, NewF);
       } else {
         assert(CB->getType() == NewRetTy &&
-               "only handle exact return type match non-void returns");
+               "only handle exact return type match with non-void returns");
       }
     }
   }