Don't look for leaf values to store when lowering stores of

empty structs. This fixes PR2612.

llvm-svn: 54226

2 files changed, 24 insertions, 2 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index 65753e53446..6267eb9fea8 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -2928,9 +2928,7 @@ void SelectionDAGLowering::visitLoad(LoadInst &I) {
 
 void SelectionDAGLowering::visitStore(StoreInst &I) {
   Value *SrcV = I.getOperand(0);
-  SDValue Src = getValue(SrcV);
   Value *PtrV = I.getOperand(1);
-  SDValue Ptr = getValue(PtrV);
 
   SmallVector<MVT, 4> ValueVTs;
   SmallVector<uint64_t, 4> Offsets;
@@ -2939,6 +2937,12 @@ void SelectionDAGLowering::visitStore(StoreInst &I) {
   if (NumValues == 0)
     return;
 
+  // Get the lowered operands. Note that we do this after
+  // checking if NumResults is zero, because with zero results
+  // the operands won't have values in the map.
+  SDValue Src = getValue(SrcV);
+  SDValue Ptr = getValue(PtrV);
+
   SDValue Root = getRoot();
   SmallVector<SDValue, 4> Chains(NumValues);
   MVT PtrVT = Ptr.getValueType();
diff --git a/llvm/test/CodeGen/Generic/empty-load-store.ll b/llvm/test/CodeGen/Generic/empty-load-store.ll
new file mode 100644
index 00000000000..d7bb37194e4
--- /dev/null
+++ b/llvm/test/CodeGen/Generic/empty-load-store.ll
@@ -0,0 +1,18 @@
+; RUN: llvm-as < %s | llc
+; PR2612
+
+@current_foo = internal global {  } zeroinitializer
+
+define i32 @foo() {
+entry:
+        %retval = alloca i32
+        store i32 0, i32* %retval
+        %local_foo = alloca {  }
+        load {  }* @current_foo
+        store {  } %0, {  }* %local_foo
+        br label %return
+
+return:
+        load i32* %retval
+        ret i32 %1
+}