Add support for return value promotion in X86 calling conventions.

Patch by Yiannis Tsiouris!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157757 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 58af729..f3b66e4 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -1504,6 +1504,16 @@
     SDValue ValToCopy = OutVals[i];
     EVT ValVT = ValToCopy.getValueType();
 
+    // Promote values to the appropriate types
+    if (VA.getLocInfo() == CCValAssign::SExt)
+      ValToCopy = DAG.getNode(ISD::SIGN_EXTEND, dl, VA.getLocVT(), ValToCopy);
+    else if (VA.getLocInfo() == CCValAssign::ZExt)
+      ValToCopy = DAG.getNode(ISD::ZERO_EXTEND, dl, VA.getLocVT(), ValToCopy);
+    else if (VA.getLocInfo() == CCValAssign::AExt)
+      ValToCopy = DAG.getNode(ISD::ANY_EXTEND, dl, VA.getLocVT(), ValToCopy);
+    else if (VA.getLocInfo() == CCValAssign::BCvt)
+      ValToCopy = DAG.getNode(ISD::BITCAST, dl, VA.getLocVT(), ValToCopy);
+
     // If this is x86-64, and we disabled SSE, we can't return FP values,
     // or SSE or MMX vectors.
     if ((ValVT == MVT::f32 || ValVT == MVT::f64 ||