[Attributor][Fix] Use right type to replace expressions

Summary: This should be obsolete once the functionality in D66967 is integrated.

Reviewers: uenoku, sstefan1

Subscribers: hiraditya, bollu, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67231

llvm-svn: 371915

2 files changed, 19 insertions, 3 deletions

diff --git a/llvm/lib/Transforms/IPO/Attributor.cpp b/llvm/lib/Transforms/IPO/Attributor.cpp
index 94ed7003c96..b9f943e4772 100644
--- a/llvm/lib/Transforms/IPO/Attributor.cpp
+++ b/llvm/lib/Transforms/IPO/Attributor.cpp
@@ -874,12 +874,17 @@ ChangeStatus AAReturnedValuesImpl::manifest(Attributor &A) {
     if (Function *F = dyn_cast<Function>(&AnchorValue)) {
       for (const Use &U : F->uses())
         if (CallBase *CB = dyn_cast<CallBase>(U.getUser()))
-          if (CB->isCallee(&U))
-            Changed = ReplaceCallSiteUsersWith(*CB, *RVC) | Changed;
+          if (CB->isCallee(&U)) {
+            Constant *RVCCast =
+                ConstantExpr::getTruncOrBitCast(RVC, CB->getType());
+            Changed = ReplaceCallSiteUsersWith(*CB, *RVCCast) | Changed;
+          }
     } else {
       assert(isa<CallBase>(AnchorValue) &&
              "Expcected a function or call base anchor!");
-      Changed = ReplaceCallSiteUsersWith(cast<CallBase>(AnchorValue), *RVC);
+      Constant *RVCCast =
+          ConstantExpr::getTruncOrBitCast(RVC, AnchorValue.getType());
+      Changed = ReplaceCallSiteUsersWith(cast<CallBase>(AnchorValue), *RVCCast);
     }
     if (Changed == ChangeStatus::CHANGED)
       STATS_DECLTRACK(UniqueConstantReturnValue, FunctionReturn,
diff --git a/llvm/test/Transforms/FunctionAttrs/arg_returned.ll b/llvm/test/Transforms/FunctionAttrs/arg_returned.ll
index 6e57475c579..95871ff7d34 100644
--- a/llvm/test/Transforms/FunctionAttrs/arg_returned.ll
+++ b/llvm/test/Transforms/FunctionAttrs/arg_returned.ll
@@ -827,6 +827,17 @@ define i32 @exact(i32* %a) {
   ret i32 %add3
 }
 
+@G = external global i8
+define i32* @ret_const() #0 {
+  %bc = bitcast i8* @G to i32*
+  ret i32* %bc
+}
+define i32* @use_const() #0 {
+  %c = call i32* @ret_const()
+  ; CHECK: ret i32* bitcast (i8* @G to i32*)
+  ret i32* %c
+}
+
 attributes #0 = { noinline nounwind uwtable }
 
 ; BOTH-NOT: attributes #