Merging r197036:

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r197036 | david.tweed | 2013-12-11 08:39:46 -0500 (Wed, 11 Dec 2013) | 8 lines

Add front-end infrastructure now address space casts are in LLVM IR.

With the introduction of explicit address space casts into LLVM, there's
a need to provide a new cast kind the front-end can create for C/OpenCL/CUDA
and code to produce address space casts from those kinds when appropriate.

Patch by Michele Scandale!

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llvm-svn: 209029