search for: arrtest

...l -print-after-all -time-passes 1. Only programs that make no use of arrays appear to always be processed correctly by llc (nvptx target). Some programs using arrays, make llc "hang" (runs endlessly). 2. One small C function exposing this behavior is as follows: // start here int arrtest (int x, int y) { unsigned char b[3]={0x10,0x30,0x55}; b[0] = (255 - b[x]) + b[y]; // doesn't work! // b[0] = (255 - b[0]) + b[1]; // works b[1] = x - y; b[2] = x * y; return b[0]; } // end here 3. A change that makes this function compilable (also visible in the comments) Ch...

...ess space 0. In the back-end, address space 0 is the PTX generic address space and global variables cannot use it. The index computations are not causing this issue. The following change would work: // start here __attribute__((address_space(3))) static unsigned char b[3]={0x10,0x30,0x55}; int arrtest (int x, int y) { b[0] = (255 - b[x]) + b[y]; // now it works! // b[0] = (255 - b[0]) + b[1]; // works b[1] = x - y; b[2] = x * y; return b[0]; } // end here If you compile LLVM in debug mode, you would have seen a failure about an unknown address space. I just committed a change in r17...