If there's an unaligned memcpy to/from the stack, don't lower it. Just call the
memcpy library function instead.
llvm-svn: 43270
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index 610c898..71999b4 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -4329,6 +4329,19 @@
}
}
+ // Check to see if there is an unaligned memcpy from/onto the stack. If
+ // so, then ignore it for the present.
+ if (Op1.getOpcode() == ISD::FrameIndex ||
+ Op2.getOpcode() == ISD::FrameIndex) {
+ unsigned TotalSize = 0;
+
+ for (unsigned i = 0; i < NumMemOps; i++)
+ TotalSize += MVT::getSizeInBits(MemOps[i]) / 8;
+
+ if (TotalSize % Align != 0)
+ break;
+ }
+
for (unsigned i = 0; i < NumMemOps; i++) {
MVT::ValueType VT = MemOps[i];
unsigned VTSize = MVT::getSizeInBits(VT) / 8;