Make array bound checks optional and disabled by default.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@1725 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/ExecutionEngine/Interpreter/Execution.cpp b/lib/ExecutionEngine/Interpreter/Execution.cpp
index d92764e..d3aa4cc 100644
--- a/lib/ExecutionEngine/Interpreter/Execution.cpp
+++ b/lib/ExecutionEngine/Interpreter/Execution.cpp
@@ -26,7 +26,7 @@
 
 cl::Flag   QuietMode ("quiet"  , "Do not emit any non-program output");
 cl::Alias  QuietModeA("q"      , "Alias for -quiet", cl::NoFlags, QuietMode);
-
+cl::Flag   ArrayChecksEnabled("array-checks", "Enable array bound checks");
 
 // Create a TargetData structure to handle memory addressing and size/alignment
 // computations
@@ -797,7 +797,7 @@
       assert(I->getOperand(ArgOff)->getType() == Type::UIntTy);
       unsigned Idx = getOperandValue(I->getOperand(ArgOff++), SF).UIntVal;
       if (const ArrayType *AT = dyn_cast<ArrayType>(ST))
-        if (Idx >= AT->getNumElements()) {
+        if (Idx >= AT->getNumElements() && ArrayChecksEnabled) {
           cerr << "Out of range memory access to element #" << Idx
                << " of a " << AT->getNumElements() << " element array."
                << " Subscript #" << (ArgOff-I->getFirstIndexOperandNumber())