[LLVMdev] Question about NoWrap flag for SCEVAddRecExpr

[Sanjoy Das]

> Base is treated as unsigned so 0xff…ff + 1 would be 0x100…00

This is the part I was missing, thanks for pointing out the FAQ.  So
the infinitely precise address computed by a GEP is

zext(Base) + sext(Idx0) + sext(Idx1) ... ?

> 0x100…00 which would be out of bounds (sort of).

Does this mean, for C++ programs of the form,

  for (int *I = array, *E = array + size; I != E; ++I)
   ...

the memory allocator has to guarantee that array cannot span
[0xff..fffff-31,0xff..fffff] (both inclusive) with size == 32?

-- Sanjoy