propagate struct size and alignment of byval arguments to the DAG

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40986 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 3af3934..184e355 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -1260,7 +1260,12 @@
       int FI = MFI->CreateFixedObject(MVT::getSizeInBits(VA.getValVT())/8,
                                       VA.getLocMemOffset());
       SDOperand FIN = DAG.getFrameIndex(FI, getPointerTy());
-      ArgValues.push_back(DAG.getLoad(VA.getValVT(), Root, FIN, NULL, 0));
+
+      unsigned Flags =  cast<ConstantSDNode>(Op.getOperand(3 + i))->getValue();
+      if (Flags & ISD::ParamFlags::ByVal)
+        ArgValues.push_back(FIN);
+      else
+        ArgValues.push_back(DAG.getLoad(VA.getValVT(), Root, FIN, NULL, 0));
     }
   }