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Hi, I've prepared patches for both LLVM and Clang to change the datalayout for R600. This may seem like a bold move, but I think it is warranted. R600/SI is a strange architecture in that it uses 64bit pointers but does not support 64 bit arithmetic except for load/store operations that roughly map onto getelementptr. The current datalayout for r600 includes n32:64, which is odd