Forum Discussion

eheim's avatar
eheim
Icon for New Contributor rankNew Contributor
7 years ago
Solved

OpenCL Compiler Local Memory Address Space Splitter fails

Hello, when compiling my OpenCL kernels with AOCL 17.1, I get the following error: aoc: Optimizing and doing static analysis of code...aocl-opt: Value.cpp:287: void llvm::Value::replaceAllUsesWith(...
  • eheim's avatar
    eheim
    7 years ago

    Thank you for your reply, AKert. It is great to hear that my report is of some value. Meanwhile, I have found that the issue seems to be caused by reading from global memory and writing to an Intel FPGA channel in a single statement. When replacing

    UTL_WRITE_CH(ch_1, data1[j]);
UTL_WRITE_CH(ch_2, buf_d2[i]);

    with (make sure to use the actual types)

    const my_type1 temp1 data1[j]
UTL_WRITE_CH(ch_1, temp1);
 
const my_type2 temp2 buf_d2[i]
UTL_WRITE_CH(ch_2, temp2);

    the error goes away. It may or may not be related to also using char (8 bits) buffers.

HRZ's avatar
HRZ
Icon for Frequent Contributor rankFrequent Contributor
7 years ago

This is an internal crash in the OpenCL compiler. Nobody knows (or could possibly know) why it happens other than Intel's engineers who created the compiler. My recommendation is to try other (preferably newer) versions of the compiler to see if the issue has been fixed. If not, you have no choice but to change your design strategy. Such crashes are more frequent in designs which are not very FPGA-friendly.