[PATCH] IR: Do not canonicalize constant GEPs into an out-of-bounds array access

[David Majnemer]

================
Comment at: lib/IR/ConstantFold.cpp:1975
@@ +1974,3 @@
+          if (ConstantInt *CIIdx0 = dyn_cast<ConstantInt>(Idx0))
+            if (CIIdx0->getSExtValue() < NumElements)
+              IsSequentialAccessInRange = true;
----------------
Bill Wendling wrote:
> Please do a zext instead of sext.
GEP values which are negative are out of bounds which is why all this work is done with signed comparisons and signed types.


http://llvm-reviews.chandlerc.com/D2093