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

[Rafael Ávila de Espíndola]

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Comment at: lib/Target/X86/X86ISelLowering.cpp:2307
@@ +2306,3 @@
+    AttributeSet Attrs = MF.getFunction()->getAttributes();
+    for (; I != E; ++I)
+      if (Attrs.hasAttribute(I + 1, Attribute::StructRet))
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Why the loop? If the rest of the code assumes that it is the first or second, it seems better to check only those too, or at least assert that I is 0 or 1.

http://reviews.llvm.org/D3617