[PATCH] Allow sret on the second parameter as well as the first

[David Majnemer]

LGTM

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Comment at: lib/Target/X86/X86ISelLowering.cpp:2310
@@ -2306,1 +2309,3 @@
+        break;
+    SDValue Copy = DAG.getCopyToReg(DAG.getEntryNode(), dl, Reg, InVals[I]);
     Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Copy, Chain);
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We should assert `I != E`.

http://reviews.llvm.org/D3617