Avoid creating virtual registers for unused values.

llvm-svn: 101480

2 files changed, 5 insertions, 5 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 412de1c89bb..71da0ab3e56 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -918,10 +918,10 @@ void SelectionDAGBuilder::visitRet(const ReturnInst &I) {
 /// created for it, emit nodes to copy the value into the virtual
 /// registers.
 void SelectionDAGBuilder::CopyToExportRegsIfNeeded(const Value *V) {
-  if (!V->use_empty()) {
-    DenseMap<const Value *, unsigned>::iterator VMI = FuncInfo.ValueMap.find(V);
-    if (VMI != FuncInfo.ValueMap.end())
-      CopyValueToVirtualRegister(V, VMI->second);
+  DenseMap<const Value *, unsigned>::iterator VMI = FuncInfo.ValueMap.find(V);
+  if (VMI != FuncInfo.ValueMap.end()) {
+    assert(!V->use_empty() && "Unused value assigned virtual registers!");
+    CopyValueToVirtualRegister(V, VMI->second);
   }
 }
 
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index 7436bbea723..9082fb6fbe9 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -834,7 +834,7 @@ void SelectionDAGISel::SelectAllBasicBlocks(const Function &Fn) {
             BI->dump();
           }
 
-          if (!BI->getType()->isVoidTy()) {
+          if (!BI->getType()->isVoidTy() && !BI->use_empty()) {
             unsigned &R = FuncInfo->ValueMap[BI];
             if (!R)
               R = FuncInfo->CreateRegForValue(BI);