In some cases it is possible for CGP to attempt to reuse a base address from
another basic block. In those cases we have to be sure that all the address
math was either done at the same bit width, or that none of it overflowed
before it was extended.
Patch by Louis Gerbarg <lgg@apple.com>
rdar://16307442
llvm-svn: 204833
Jim Grosbach