derekbruening
commented
4 years ago Pasting from PR #4325 :
Here's the key test in the new Travis job for drcachesim: https://travis-ci.com/github/DynamoRIO/dynamorio/jobs/353366354
3109 Start 6: code_api|tool.drcacheoff.altbindir
3110
31116: Test command: /home/travis/build/DynamoRIO/dynamorio/build_aarch64-on-x86/bin64/runstats "-s" "90" "-killpg" "-silent" "-env" "LD_LIBRARY_PATH" "/home/travis/build/DynamoRIO/dynamorio/build_aarch64-on-x86/lib64/debug:/home/travis/build/DynamoRIO/dynamorio/build_aarch64-on-x86/ext/lib64/debug:" "-env" "DYNAMORIO_OPTIONS" "-stderr_mask 0xC -dumpcore_mask 0 -code_api" "/home/travis/build/DynamoRIO/dynamorio/build_aarch64-on-x86/clients/bin64/drcachesim" "-indir" "/home/travis/build/DynamoRIO/dynamorio/build_aarch64-on-x86/drmemtrace.threadsig.aarch64" "-simulator_type" "opcode_mix" "-alt_module_dir" "/home/travis/build/DynamoRIO/dynamorio/clients/drcachesim/tests/drmemtrace.threadsig.aarch64.raw" "-module_file" "/home/travis/build/DynamoRIO/dynamorio/build_aarch64-on-x86/drmemtrace.threadsig.aarch64/raw/modules.log"
31165/6 Test #5: code_api|api.drdecode ................ Passed 0.00 sec
31176: Opcode mix tool results:
31186: 125442 : total executed instructions
31196: 15742 : bcond
31206: 15165 : stp
31216: 13670 : subs
31226: 12240 : add
31236: 8286 : and
31246: 6059 : xx
...So it's x86 drraw2trace and opcode_mix analyzers operating on aarch64 traces. Pretty cool.
It is useful to be able to analyze and post-process drcachesim offline traces gathered on one architecture on a different platform: e.g., to trace an ARM application and pull the trace onto an x86 machine for analysis.
Most of the analysis code is already cross-platform, but the decoder for tools like opcode_mix is the key missing piece. We would need something like #1684 to continue using DR's decoder there, but we'd need it in full DR and not just drdecodelib (because raw2trace uses full DR and it is complex to downgrade it).