When we record and replay kernels we should not error out early if there
is a chance the program might still run fine. This patch will:
1) Fallback to the allocation heuristic if the VAMap doesn't work.
2) Adjust the memory start to match the required address if possible.
3) Adjust the (guessed) pointer arguments if the memory start adjustment
is impossible. This will allow kernels without indirect accesses to
work while indirect accesses will most likely fail.
The commit was discussed in phabricator
(https://reviews.llvm.org/D157186).
Record replay currently fails on AMD as it conflicts with the heap
memory allocator introduced in #69806. The workaround is setting
`LIBOMPTARGET_HEAP_SIZE=0` during both record and replay run.
Enable record-replay for OpenMP offload kernels. On recording the initialization
is performed on device initialization by reading env variables. (This is similar to
the way rr used to operate). The primary change takes place in the replay phase
with the replay tool explicitly initializing the record-replay functionality.
Differential Revision: https://reviews.llvm.org/D156174
Fix
This patch adds functionality for recording and replaying the execution of OpenMP offload kernels, based on an original implementation by Steve Rangel. The patch extends libomptarget to extract a json description of the kernel, the device image binary, and a device memory snapshot before and after the execution of a recorded kernel. Kernel recording/replaying in libomptarget is controlled through env vars (LIBOMPTARGET_RECORD, LIBOMPTARGET_REPLAY). It provides a tool, llvm-omp-kernel-replay, for replaying a kernel using the extracted information with the ability to verify replayed execution using the post-execution device memory snapshot, also supporting changing the number of teams/threads for replaying.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D138931
