This reverts commit
https://github.com/llvm/llvm-project/commit/87b7f63a117c340a6d9ca47959335fd7ef6c7ad2,
reapplying

https://github.com/llvm/llvm-project/commit/7e66cf74fb4e6a103f923e34700a7b6f20ac2a9b
with a small (and probably temporary)
change to generate more debug info to help with diagnosing buildbot
issues.

This reverts commit 7e66cf74fb4e6a103f923e34700a7b6f20ac2a9b.

Breaking green dragon:

https://green.lab.llvm.org/job/llvm.org/view/LLDB/job/as-lldb-cmake/19569/testReport/junit/lldb-api/functionalities_reverse-execution/TestReverseContinueWatchpoints_py/

This reverts commit a774de807e56c1147d4630bfec3110c11d41776e.

This is the same changes as last time, plus:
* We load the binary into the target object so that on Windows, we can
resolve the locations of the functions.
* We now assert that each required breakpoint has at least 1 location,
to prevent an issue like that in the future.
* We are less strict about the unsupported error message, because it
prints "error: windows" on Windows instead of "error: gdb-remote".

Reverts llvm/llvm-project#123945

Has failed on the Windows on Arm buildbot:
https://lab.llvm.org/buildbot/#/builders/141/builds/5865
```
********************
Unresolved Tests (2):
  lldb-api :: functionalities/reverse-execution/TestReverseContinueBreakpoints.py
  lldb-api :: functionalities/reverse-execution/TestReverseContinueWatchpoints.py
********************
Failed Tests (1):
  lldb-api :: functionalities/reverse-execution/TestReverseContinueNotSupported.py
```
Reverting while I reproduce locally.

This reverts commit 22561cfb443267905d4190f0e2a738e6b412457f and fixes
b7b9ccf44988edf49886743ae5c3cf4184db211f (#112079).

The problem is that x86_64 and Arm 32-bit have memory regions above the
stack that are readable but not writeable. First Arm:
```
(lldb) memory region --all
<...>
[0x00000000fffcf000-0x00000000ffff0000) rw- [stack]
[0x00000000ffff0000-0x00000000ffff1000) r-x [vectors]
[0x00000000ffff1000-0xffffffffffffffff) ---
```
Then x86_64:
```
$ cat /proc/self/maps
<...>
7ffdcd148000-7ffdcd16a000 rw-p 00000000 00:00 0                          [stack]
7ffdcd193000-7ffdcd196000 r--p 00000000 00:00 0                          [vvar]
7ffdcd196000-7ffdcd197000 r-xp 00000000 00:00 0                          [vdso]
ffffffffff600000-ffffffffff601000 --xp 00000000 00:00 0                  [vsyscall]
```
Compare this to AArch64 where the test did pass:
```
$ cat /proc/self/maps
<...>
ffffb87dc000-ffffb87dd000 r--p 00000000 00:00 0                          [vvar]
ffffb87dd000-ffffb87de000 r-xp 00000000 00:00 0                          [vdso]
ffffb87de000-ffffb87e0000 r--p 0002a000 00:3c 76927217                   /usr/lib/aarch64-linux-gnu/ld-linux-aarch64.so.1
ffffb87e0000-ffffb87e2000 rw-p 0002c000 00:3c 76927217                   /usr/lib/aarch64-linux-gnu/ld-linux-aarch64.so.1
fffff4216000-fffff4237000 rw-p 00000000 00:00 0                          [stack]
```
To solve this, look up the memory region of the stack pointer (using
https://lldb.llvm.org/resources/lldbgdbremote.html#qmemoryregioninfo-addr)
and constrain the read to within that region. Since we know the stack is
all readable and writeable.

I have also added skipIfRemote to the tests, since getting them working
in that context is too complex to be worth it.

Memory write failures now display the range they tried to write, and
register write errors will show the name of the register where possible.

The patch also includes a workaround for a an issue where the test code
could mistake an `x` response that happens to begin with an `O` for an
output packet (stdout). This workaround will not be necessary one we
start using the [new
implementation](https://discourse.llvm.org/t/rfc-fixing-incompatibilties-of-the-x-packet-w-r-t-gdb/84288)
of the `x` packet.

---------

Co-authored-by: Pavel Labath <pavel@labath.sk>

.. by changing the signal stop reason format :facepalm:

The reason this did not work is because the code in
`StopInfo::GetCrashingDereference` was looking for the string "address="
to extract the address of the crash. Macos stop reason strings have the
form
```
  EXC_BAD_ACCESS (code=1, address=0xdead)
```
while on linux they look like:
```
  signal SIGSEGV: address not mapped to object (fault address: 0xdead)
```

Extracting the address from a string sounds like a bad idea, but I
suppose there's some value in using a consistent format across
platforms, so this patch changes the signal format to use the equals
sign as well. All of the diagnose tests pass except one, which appears
to fail due to something similar #115453 (disassembler reports
unrelocated call targets).

I've left the tests disabled on windows, as the stop reason reporting
code works very differently there, and I suspect it won't work out of
the box. If I'm wrong -- the XFAIL will let us know.

Reverts llvm/llvm-project#112079 due to failures on the arm bot.

This commit adds support for a
`SBProcess::ContinueInDirection()` API. A user-accessible command for
this will follow in a later commit.

This feature depends on a gdbserver implementation (e.g. `rr`) providing
support for the `bc` and `bs` packets. `lldb-server` does not support
those packets, and there is no plan to change that. For testing
purposes, this commit adds a Python implementation of *very limited*
record-and-reverse-execute functionality, implemented as a proxy between
lldb and lldb-server in `lldbreverse.py`. This should not (and in
practice cannot) be used for anything except testing.

The tests here are quite minimal but we test that simple breakpoints and
watchpoints work as expected during reverse execution, and that
conditional breakpoints and watchpoints work when the condition calls a
function that must be executed in the forward direction.

Reverting this again; I added a commit which added @skipIfDarwin
markers to the TestReverseContinueBreakpoints.py and
TestReverseContinueNotSupported.py API tests, which use lldb-server
in gdbserver mode which does not work on Darwin.  But the aarch64 ubuntu
bot reported a failure on TestReverseContinueBreakpoints.py,
https://lab.llvm.org/buildbot/#/builders/59/builds/6397

  File "/home/tcwg-buildbot/worker/lldb-aarch64-ubuntu/llvm-project/lldb/test/API/functionalities/reverse-execution/TestReverseContinueBreakpoints.py", line 63, in test_reverse_continue_skip_breakpoint
    self.reverse_continue_skip_breakpoint_internal(async_mode=False)
  File "/home/tcwg-buildbot/worker/lldb-aarch64-ubuntu/llvm-project/lldb/test/API/functionalities/reverse-execution/TestReverseContinueBreakpoints.py", line 81, in reverse_continue_skip_breakpoint_internal
    self.expect(
  File "/home/tcwg-buildbot/worker/lldb-aarch64-ubuntu/llvm-project/lldb/packages/Python/lldbsuite/test/lldbtest.py", line 2372, in expect
    self.runCmd(
  File "/home/tcwg-buildbot/worker/lldb-aarch64-ubuntu/llvm-project/lldb/packages/Python/lldbsuite/test/lldbtest.py", line 1002, in runCmd
    self.assertTrue(self.res.Succeeded(), msg + output)
AssertionError: False is not true : Process should be stopped due to history boundary
Error output:
error: Process must be launched.

This reverts commit 4f297566b3150097de26c6a23a987d2bd5fc19c5.

This commit only adds support for the
`SBProcess::ReverseContinue()` API. A user-accessible command for this
will follow in a later commit.

This feature depends on a gdbserver implementation (e.g. `rr`) providing
support for the `bc` and `bs` packets. `lldb-server` does not support
those packets, and there is no plan to change that. So, for testing
purposes, `lldbreverse.py` wraps `lldb-server` with a Python
implementation of *very limited* record-and-replay functionality for use
by *tests only*.

The majority of this PR is test infrastructure (about 700 of the 950
lines added).