From 2c31750cd0ebdc83a890ace97dbb6249b3abe44e Mon Sep 17 00:00:00 2001
From: Dan Gohman <gohman@apple.com>
Date: Fri, 20 Jun 2008 01:03:44 +0000
Subject: [PATCH] Teach InlineFunction how to differentiate between
 multiple-value return statements and aggregate returns so that it handles
 both correctly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52519 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Transforms/Utils/InlineFunction.cpp | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/lib/Transforms/Utils/InlineFunction.cpp b/lib/Transforms/Utils/InlineFunction.cpp
index 2ed335c95c1..e917dc80b58 100644
--- a/lib/Transforms/Utils/InlineFunction.cpp
+++ b/lib/Transforms/Utils/InlineFunction.cpp
@@ -443,8 +443,9 @@ bool llvm::InlineFunction(CallSite CS, CallGraph *CG, const TargetData *TD) {
     // uses of the returned value.
     if (!TheCall->use_empty()) {
       ReturnInst *R = Returns[0];
-      if (isa<StructType>(TheCall->getType())) {
-        // Multiple return values.
+      if (isa<StructType>(TheCall->getType()) &&
+          TheCall->getType() != R->getOperand(0)->getType()) {
+        // Multiple-value return statements.
         while (!TheCall->use_empty()) {
           GetResultInst *GR = cast<GetResultInst>(TheCall->use_back());
           Value *RV = R->getOperand(GR->getIndex());
@@ -509,6 +510,13 @@ bool llvm::InlineFunction(CallSite CS, CallGraph *CG, const TargetData *TD) {
   // any users of the original call/invoke instruction.
   const Type *RTy = CalledFunc->getReturnType();
   const StructType *STy = dyn_cast<StructType>(RTy);
+
+  // We do special handling for multiple-value return statements. If this is
+  // a plain aggregate return, don't do the special handling.
+  if (!Returns.empty() && Returns[0]->getNumOperands() != 0 &&
+      Returns[0]->getOperand(0)->getType() == STy)
+    STy = 0;
+
   if (Returns.size() > 1 || STy) {
     // The PHI node should go at the front of the new basic block to merge all
     // possible incoming values.