ASSERT signal marker invariants in histogram.offline test on AArch64

[derekbruening]

Xref #2899 where this test hangs.

This is a new assert on signal marker invariants and it just fired:

http://139.178.83.194:8080/job/DynamoRIO-AArch64-Precommit/887/console

171/176 Test #168: code_api|tool.histogram.offline .................***Failed    2.98 sec
Running cmd |/var/lib/jenkins/.jenkins/workspace/DynamoRIO-AArch64-Precommit/build/build_debug-internal-64/bin64/drrun;-s;90;-quiet;-debug;-killpg;-stderr_mask;0xC;-dumpcore_mask;0;-code_api;-t;drcachesim;-offline;-subdir_prefix;tool.histogram.offline;--;/var/lib/jenkins/.jenkins/workspace/DynamoRIO-AArch64-Precommit/build/build_debug-internal-64/suite/tests/bin/pthreads.ptsig|
Running postcmd |/var/lib/jenkins/.jenkins/workspace/DynamoRIO-AArch64-Precommit/build/build_debug-internal-64/clients/bin64/drcachesim;-indir;/var/lib/jenkins/.jenkins/workspace/DynamoRIO-AArch64-Precommit/build/build_debug-internal-64/suite/tests/tool.histogram.offline.pthreads.ptsig.03302.8806.dir|
Running postcmd2 |/var/lib/jenkins/.jenkins/workspace/DynamoRIO-AArch64-Precommit/build/build_debug-internal-64/clients/bin64/histogram_launcher;-test_mode;-trace_dir;/var/lib/jenkins/.jenkins/workspace/DynamoRIO-AArch64-Precommit/build/build_debug-internal-64/suite/tests/tool.histogram.offline.pthreads.ptsig.03302.8806.dir/trace|
CMake Error at /var/lib/jenkins/.jenkins/workspace/DynamoRIO-AArch64-Precommit/suite/tests/runmulti.cmake:106 (message):
  *** postcmd2 failed (Child aborted): histogram_launcher:
  /var/lib/jenkins/.jenkins/workspace/DynamoRIO-AArch64-Precommit/clients/drcachesim/tests/trace_invariants.cpp:143:
  virtual bool trace_invariants_t::process_memref(const memref_t&): Assertion
  `memref.instr.tid != pre_signal_instr.instr.tid || memref.instr.addr ==
  pre_signal_instr.instr.addr || memref.instr.addr ==
  pre_signal_instr.instr.addr + pre_signal_instr.instr.size ||
  memref.instr.addr == app_handler_pc ||
  type_is_instr_branch(pre_signal_instr.instr.type) ||
  pre_signal_instr.instr.type == TRACE_TYPE_INSTR_SYSENTER' failed.

  ***

[derekbruening]

A similar invariant (is it the same one after code changes?) just failed on 32-bit Travis:
https://travis-ci.com/DynamoRIO/dynamorio/jobs/273998434

1225273/322 Test #274: code_api|tool.histogram.offline ..................................***Failed    2.98 sec
1226Running cmd |/home/travis/build/DynamoRIO/dynamorio/build_debug-internal-32/bin32/drrun;-s;90;-quiet;-debug;-killpg;-stderr_mask;0xC;-dumpcore_mask;0;-code_api;-t;drcachesim;-offline;-subdir_prefix;tool.histogram.offline;--;/home/travis/build/DynamoRIO/dynamorio/build_debug-internal-32/suite/tests/bin/drmemtrace.signal_invariants|
1227Running postcmd |/home/travis/build/DynamoRIO/dynamorio/build_debug-internal-32/clients/bin32/drcachesim;-indir;/home/travis/build/DynamoRIO/dynamorio/build_debug-internal-32/suite/tests/tool.histogram.offline.drmemtrace.signal_invariants.20715.6317.dir|
1228Running postcmd2 |/home/travis/build/DynamoRIO/dynamorio/build_debug-internal-32/clients/bin32/histogram_launcher;-test_mode;-trace_dir;/home/travis/build/DynamoRIO/dynamorio/build_debug-internal-32/suite/tests/tool.histogram.offline.drmemtrace.signal_invariants.20715.6317.dir/trace|
1229CMake Error at /home/travis/build/DynamoRIO/dynamorio/suite/tests/runmulti.cmake:106 (message):
1230  *** postcmd2 failed (Child aborted): histogram_launcher:
1231  /home/travis/build/DynamoRIO/dynamorio/clients/drcachesim/tests/trace_invariants.cpp:111:
1232  virtual bool trace_invariants_t::process_memref(const memref_t&): Assertion
1233  `prev_instr.instr.tid == memref.instr.tid ||
1234  thread_exited[prev_instr.instr.tid] || (prev_xfer_marker.instr.tid ==
1235  prev_instr.instr.tid && prev_xfer_marker.marker.marker_type ==
1236  TRACE_MARKER_TYPE_KERNEL_EVENT)' failed.
1237
1238  ***

[derekbruening]

Failing a lot recently. E.g.: http://139.178.83.194:8080/job/DynamoRIO-AArch64-Precommit/927/

[derekbruening]

Travis failure just hit again: https://travis-ci.com/DynamoRIO/dynamorio/jobs/274359971