[PATCH] [NVPTX] Replace addrspacecast with bitcast

[Jingyue Wu]

Hi Matt, 

Are you referring to your diff http://reviews.llvm.org/D2186? If that diff gets in, I believe the code here can be simplified a lot. 

Are you still pushing that diff? To make it more acceptable, one alternative is to implement this canonicalization as a separate pass which can be turned on by the backend when necessary.

http://reviews.llvm.org/D3586