[lldb][AArch64] Add support for memory tags in core files

This teaches ProcessElfCore to recognise the MTE tag segments.

https://www.kernel.org/doc/html/latest/arm64/memory-tagging-extension.html#c

[lldb][AArch64] Add support for memory tags in core files

This teaches ProcessElfCore to recognise the MTE tag segments.

https://www.kernel.org/doc/html/latest/arm64/memory-tagging-extension.html#core-dump-support

These segments contain all the tags for a matching memory segment
which will have the same size in virtual address terms. In real terms
it's 2 tags per byte so the data in the segment is much smaller.

Since MTE is the only tag type supported I have hardcoded some
things to those values. We could and should support more formats
as they appear but doing so now would leave code untested until that
happens.

A few things to note:
* /proc/pid/smaps is not in the core file, only the details you have
in "maps". Meaning we mark a region tagged only if it has a tag segment.
* A core file supports memory tagging if it has at least 1 memory
tag segment, there is no other flag we can check to tell if memory
tagging was enabled. (unlike a live process that can support memory
tagging even if there are currently no tagged memory regions)

Tests have been added at the commands level for a core file with
mte and without.

There is a lot of overlap between the "memory tag read" tests here and the unit tests for
MemoryTagManagerAArch64MTE::UnpackTagsFromCoreFileSegment, but I think it's
worth keeping to check ProcessElfCore doesn't cause an assert.

Depends on D129487

Reviewed By: omjavaid

Differential Revision: https://reviews.llvm.org/D129489

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[LLDB][NFC][Reliability] Fix uninitialized variables from Coverity scan. Part 2

Improve LLDB reliability by fixing the following "uninitialized variables" static code inspection warnings from
scan.c

[LLDB][NFC][Reliability] Fix uninitialized variables from Coverity scan. Part 2

Improve LLDB reliability by fixing the following "uninitialized variables" static code inspection warnings from
scan.coverity.com:

1476275, 1274012, 1455035, 1364789, 1454282
1467483, 1406152, 1406255, 1454837, 1454416
1467446, 1462022, 1461909, 1420566, 1327228
1367767, 1431254, 1467299, 1312678, 1431780
1454731, 1490403

Differential Revision: https://reviews.llvm.org/D130528

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Revert "[LLDB][NFC][Reliability] Fix uninitialized variables from Coverity scan. Part 2"

This reverts commit b9aedd94e6796e4b4866ab4c091b736b3db58cb7.

[LLDB][NFC][Reliability] Fix uninitialized variables from Coverity scan. Part 2

Improve LLDB reliability by fixing the following "uninitialized variables" static code inspection warnings from
scan.c

[LLDB][NFC][Reliability] Fix uninitialized variables from Coverity scan. Part 2

Improve LLDB reliability by fixing the following "uninitialized variables" static code inspection warnings from
scan.coverity.com:

1476275, 1274012, 1455035, 1364789, 1454282
1467483, 1406152, 1406255, 1454837, 1454416
1467446, 1462022, 1461909, 1420566, 1327228
1367767, 1431254, 1467299, 1312678, 1431780
1454731, 1490403

Differential Revision: https://reviews.llvm.org/D130528

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[lldb][AArch64] Fix corefile memory reads when there are non-address bits

Previously if you read a code/data mask before there was a valid thread
you would get the top byte mask. This meant the valu

[lldb][AArch64] Fix corefile memory reads when there are non-address bits

Previously if you read a code/data mask before there was a valid thread
you would get the top byte mask. This meant the value was "valid" as in,
don't read it again.

When using a corefile we ask for the data mask very early on and this
meant that later once you did have a thread it wouldn't read the
register to get the rest of the mask.

This fixes that and adds a corefile test generated from the same program
as in my previous change on this theme.

Depends on D118794

Reviewed By: omjavaid

Differential Revision: https://reviews.llvm.org/D122411

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Reland "[lldb] Remove non address bits when looking up memory regions"

This reverts commit 0df522969a7a0128052bd79182c8d58e00556e2f.

Additional checks are added to fix the detection of the last mem

Reland "[lldb] Remove non address bits when looking up memory regions"

This reverts commit 0df522969a7a0128052bd79182c8d58e00556e2f.

Additional checks are added to fix the detection of the last memory region
in GetMemoryRegions or repeating the "memory region" command when the
target has non-address bits.

Normally you keep reading from address 0, looking up each region's end
address until you get LLDB_INVALID_ADDR as the region end address.
(0xffffffffffffffff)

This is what the remote will return once you go beyond the last mapped region:
[0x0000fffffffdf000-0x0001000000000000) rw- [stack]
[0x0001000000000000-0xffffffffffffffff) ---

Problem is that when we "fix" the lookup address, we remove some bits
from it. On an AArch64 system we have 48 bit virtual addresses, so when
we fix the end address of the [stack] region the result is 0.
So we loop back to the start.

[0x0000fffffffdf000-0x0001000000000000) rw- [stack]
[0x0000000000000000-0x0000000000400000) ---

To fix this I added an additional check for the last range.
If the end address of the region is different once you apply
FixDataAddress, we are at the last region.

Since the end of the last region will be the last valid mappable
address, plus 1. That 1 will be removed by the ABI plugin.

The only side effect is that on systems with non-address bits, you
won't get that last catch all unmapped region from the max virtual
address up to 0xf...f.

[0x0000fffff8000000-0x0000fffffffdf000) ---
[0x0000fffffffdf000-0x0001000000000000) rw- [stack]
<ends here>

Though in some way this is more correct because that region is not
just unmapped, it's not mappable at all.

No extra testing is needed because this is already covered by
TestMemoryRegion.py, I simply forgot to run it on system that had
both top byte ignore and pointer authentication.

This change has been tested on a qemu VM with top byte ignore,
memory tagging and pointer authentication enabled.

Reviewed By: omjavaid

Differential Revision: https://reviews.llvm.org/D115508

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[lldb] Rename Logging.h to LLDBLog.h and clean up includes

Most of our code was including Log.h even though that is not where the
"lldb" log channel is defined (Log.h defines the generic logging
inf

[lldb] Rename Logging.h to LLDBLog.h and clean up includes

Most of our code was including Log.h even though that is not where the
"lldb" log channel is defined (Log.h defines the generic logging
infrastructure). This worked because Log.h included Logging.h, even
though it should.

After the recent refactor, it became impossible the two files include
each other in this direction (the opposite inclusion is needed), so this
patch removes the workaround that was put in place and cleans up all
files to include the right thing. It also renames the file to LLDBLog to
better reflect its purpose.

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[lldb] Convert "LLDB" log channel to the new API

[lldb] [Process/elf-core] Disable for FreeBSD vmcores

Recognize FreeBSD vmcores (kernel core dumps) through OS ABI = 0xFF
+ ELF version = 0, and do not process them via the elf-core plugin.
While th

[lldb] [Process/elf-core] Disable for FreeBSD vmcores

Recognize FreeBSD vmcores (kernel core dumps) through OS ABI = 0xFF
+ ELF version = 0, and do not process them via the elf-core plugin.
While these files use ELF as a container format, they contain raw memory
dump rather than proper VM segments and therefore are not usable
to the elf-core plugin.

Differential Revision: https://reviews.llvm.org/D114967

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Revert "Reland "[lldb] Remove non address bits when looking up memory regions""

This reverts commit fac3f20de55769d028bd92220e74f22fa57dd4b2.

I found this has broken how we detect the last memory r

Revert "Reland "[lldb] Remove non address bits when looking up memory regions""

This reverts commit fac3f20de55769d028bd92220e74f22fa57dd4b2.

I found this has broken how we detect the last memory region in
GetMemoryRegions/"memory region" command.

When you're debugging an AArch64 system with pointer authentication,
the ABI plugin will remove the top bit from the end address of the last
user mapped area.

(lldb)
[0x0000fffffffdf000-0x0001000000000000) rw- [stack]

ABI plugin removes anything above the 48th bit (48 bit virtual addresses
by default on AArch64, leaving an address of 0.

(lldb)
[0x0000000000000000-0x0000000000400000) ---

You get back a mapping for 0 and get into an infinite loop.

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Reland "[lldb] Remove non address bits when looking up memory regions"

This reverts commit 5fbcf677347e38718461496d9e9e184a7a30c3fb.

ProcessDebugger is used in ProcessWindows and NativeProcessWindo

Reland "[lldb] Remove non address bits when looking up memory regions"

This reverts commit 5fbcf677347e38718461496d9e9e184a7a30c3fb.

ProcessDebugger is used in ProcessWindows and NativeProcessWindows.
I thought I was simplifying things by renaming to DoGetMemoryRegionInfo
in ProcessDebugger but the Native process side expects "GetMemoryRegionInfo".

Follow the pattern that WriteMemory uses. So:
* ProcessWindows::DoGetMemoryRegioninfo calls ProcessDebugger::GetMemoryRegionInfo
* NativeProcessWindows::GetMemoryRegionInfo does the same

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Revert "[lldb] Remove non address bits when looking up memory regions"

This reverts commit 6f5ce43b433706c3ae5c37022d6c0964b6bfadf8 due to
build failure on Windows.

[lldb] Remove non address bits when looking up memory regions

On AArch64 we have various things using the non address bits
of pointers. This means when you lookup their containing region
you won't f

[lldb] Remove non address bits when looking up memory regions

On AArch64 we have various things using the non address bits
of pointers. This means when you lookup their containing region
you won't find it if you don't remove them.

This changes Process GetMemoryRegionInfo to a non virtual method
that uses the current ABI plugin to remove those bits. Then it
calls DoGetMemoryRegionInfo.

That function does the actual work and is virtual to be overriden
by Process implementations.

A test case is added that runs on AArch64 Linux using the top
byte ignore feature.

Reviewed By: omjavaid

Differential Revision: https://reviews.llvm.org/D102757

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[lldb] Remove ConstString from Process, ScriptInterpreter and StructuredData plugin names

Remove ConstString from DynamicLoader, JITLoader and Instruction plugin names

[lldb] Return StringRef from PluginInterface::GetPluginName

There is no reason why this function should be returning a ConstString.

While modifying these files, I also fixed several instances where

[lldb] Return StringRef from PluginInterface::GetPluginName

There is no reason why this function should be returning a ConstString.

While modifying these files, I also fixed several instances where
GetPluginName and GetPluginNameStatic were returning different strings.

I am not changing the return type of GetPluginNameStatic in this patch, as that
would necessitate additional changes, and this patch is big enough as it is.

Differential Revision: https://reviews.llvm.org/D111877

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[lldb] Remove PluginInterface::GetPluginVersion

In all these years, we haven't found a use for this function (it has
zero callers). Lets just remove the boilerplate.

Differential Revision: https://

[lldb] Remove PluginInterface::GetPluginVersion

In all these years, we haven't found a use for this function (it has
zero callers). Lets just remove the boilerplate.

Differential Revision: https://reviews.llvm.org/D109600

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[nfc] [lldb] Prevent needless copies of DataExtractor

lldb_private::DataExtractor contains DataBufferSP m_data_sp which is
relatively expensive to copy (due to multi-threading locking).

llvm::DataE

[nfc] [lldb] Prevent needless copies of DataExtractor

lldb_private::DataExtractor contains DataBufferSP m_data_sp which is
relatively expensive to copy (due to multi-threading locking).

llvm::DataExtractor does not have this problem as it uses StringRef
instead.

The copy constructor is explicit as otherwise it is easy to make
unintended modification of a local copy instead of a caller's instance
(D107470 but that is llvm::DataExtractor).

Reviewed By: clayborg

Differential Revision: https://reviews.llvm.org/D107485

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[lldb] [Process/elf-core] Fix reading NetBSD/i386 core dumps

Add support for extracting basic data from NetBSD/i386 core dumps.
FPU registers are not supported at the moment.

Differential Revision:

[lldb] [Process/elf-core] Fix reading NetBSD/i386 core dumps

Add support for extracting basic data from NetBSD/i386 core dumps.
FPU registers are not supported at the moment.

Differential Revision: https://reviews.llvm.org/D101091

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[lldb][NFC] Use C++ versions of the deprecated C standard library headers

The C headers are deprecated so as requested in D102845, this is replacing them
all with their (not deprecated) C++ equivale

[lldb][NFC] Use C++ versions of the deprecated C standard library headers

The C headers are deprecated so as requested in D102845, this is replacing them
all with their (not deprecated) C++ equivalent.

Reviewed By: shafik

Differential Revision: https://reviews.llvm.org/D103084

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[Process/elf-core] Read PID from FreeBSD prpsinfo

Add a function to read NT_PRPSINFO note from FreeBSD core dumps. This
is necessary to get the process ID (NT_PRSTATUS has only thread ID).
Move the

[Process/elf-core] Read PID from FreeBSD prpsinfo

Add a function to read NT_PRPSINFO note from FreeBSD core dumps. This
is necessary to get the process ID (NT_PRSTATUS has only thread ID).
Move the lp64 check from NT_PRSTATUS parsing to the parseFreeBSDNotes()
to avoid repeating it.

Differential Revision: https://reviews.llvm.org/D101893

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[elf-core] Improve reading memory from core file

This patch tries to improve memory-read from core files
(in order to improve disassembly functionality).

I am using RHEL 7.7 (linux kernel 3.10) and

[elf-core] Improve reading memory from core file

This patch tries to improve memory-read from core files
(in order to improve disassembly functionality).

I am using RHEL 7.7 (linux kernel 3.10) and for a lot of cases,
I was not able to disassemble some functions from backtrace when
debugging crashes from core files. It outputs some dummy code.

The cause of the problem was the fact we are returning all the zeros
from ProcessElfCore::ReadMemory() that is being called within
Disassembler::ParseInstructions() and it disassembles some dummy
opcodes from the buffer returned. Therefore, we are removing zero
bytes filling (padding) completely.

Differential Revision: https://reviews.llvm.org/D93939

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[ThreadPlan] fix exec on Linux

[lldb] Prevent 'process connect' from using local-only plugins

Add a 'can_connect' parameter to Process plugin initialization, and use
it to filter plugins to these capable of remote connections. T

[lldb] Prevent 'process connect' from using local-only plugins

Add a 'can_connect' parameter to Process plugin initialization, and use
it to filter plugins to these capable of remote connections. This is
used to prevent 'process connect' from picking up a plugin that can only
be used locally, e.g. the legacy FreeBSD plugin.

Differential Revision: https://reviews.llvm.org/D91810

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[trace][intel-pt] Scaffold the 'thread trace start | stop' commands

Depends on D90490.

The stop command is simple and invokes the new method Trace::StopTracingThread(thread).

On the other hand, th

[trace][intel-pt] Scaffold the 'thread trace start | stop' commands

Depends on D90490.

The stop command is simple and invokes the new method Trace::StopTracingThread(thread).

On the other hand, the start command works by delegating its implementation to a CommandObject provided by the Trace plugin. This is necessary because each trace plugin needs different options for this command. There's even the chance that a Trace plugin can't support live tracing, but instead supports offline decoding and analysis, which means that "thread trace dump instructions" works but "thread trace start" doest. Because of this and a few other reasons, it's better to have each plugin provide this implementation.

Besides, I'm using the GetSupportedTraceType method introduced in D90490 to quickly infer what's the trace plug-in that works for the current process.

As an implementation note, I moved CommandObjectIterateOverThreads to its header so that I can use it from the IntelPT plugin. Besides, the actual start and stop logic for intel-pt is not part of this diff.

Reviewed By: clayborg

Differential Revision: https://reviews.llvm.org/D90729

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