[DynInst_API:] [dyninst/dyninst] cf195a: Fix instrumentation regressions for libc-2.29 on A...

[Xiaozhu Meng <noreply@xxxxxxxxxx>]

  Branch: refs/heads/master
  Home:   https://github.com/dyninst/dyninst
  Commit: cf195af6655d688a611e499c43a88efc8dd2e0fb
      https://github.com/dyninst/dyninst/commit/cf195af6655d688a611e499c43a88efc8dd2e0fb
  Author: Xiaozhu Meng <mxz297@xxxxxxxxx>
  Date:   2019-11-16 (Sat, 16 Nov 2019)

  Changed paths:
    M dataflowAPI/src/liveness.C
    M dyninstAPI/src/dynProcess.C
    M dyninstAPI/src/dynProcess.h
    M dyninstAPI/src/emit-aarch64.C
    M dyninstAPI/src/pcEventHandler.C
    M dyninstAPI/src/pcEventHandler.h
    M dyninstAPI_RT/h/dyninstAPI_RT.h
    M dyninstAPI_RT/src/RTcommon.c
    M dyninstAPI_RT/src/RTcommon.h
    M dyninstAPI_RT/src/RTlinux.c
    M dyninstAPI_RT/src/RTthread-aarch64.c
    M proccontrol/src/linux.C
    M stackwalk/src/linuxbsd-swk.C

  Log Message:
  -----------
  Fix instrumentation regressions for libc-2.29 on ARM (#653)

* Fixes loading pre-instrumentation register values on aarch64
* Fix the handling of trap instruction on ARM for register liveness analysis
* Implement a byte matching heuristic for determining the length of _start
* Implement a spin lock use __atomic_test_and_set on ARM
*   1. Change stop signal from SIGBUS to (SIGRTMIN + 4) in dyninstAPI_RT.
*   2. In dyninstAPI, only do dyninstRT signal check if the signal is indeed (SIGRTMIN + 4)
* Refacotr BPatch and DyninstRT to use breakpoint as the way of communication