[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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Reland "[LLDB][NFC] Decouple dwarf location table from DWARFExpression."

This reland 227dffd0b6d78154516ace45f6ed28259c7baa48 and
562c3467a6738aa89203f72fc1d1343e5baadf3c with failed api tests fixed

Reland "[LLDB][NFC] Decouple dwarf location table from DWARFExpression."

This reland 227dffd0b6d78154516ace45f6ed28259c7baa48 and
562c3467a6738aa89203f72fc1d1343e5baadf3c with failed api tests fixed by keeping
function base file addres in DWARFExpressionList.

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Revert "[LLDB][NFC] Decouple dwarf location table from DWARFExpression."

This reverts commit 227dffd0b6d78154516ace45f6ed28259c7baa48 and its
follow up 562c3467a6738aa89203f72fc1d1343e5baadf3c becau

Revert "[LLDB][NFC] Decouple dwarf location table from DWARFExpression."

This reverts commit 227dffd0b6d78154516ace45f6ed28259c7baa48 and its
follow up 562c3467a6738aa89203f72fc1d1343e5baadf3c because it breaks a
bunch of tests on GreenDragon:

https://green.lab.llvm.org/green/view/LLDB/job/lldb-cmake/45155/

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[LLDB][NFC] Decouple dwarf location table from DWARFExpression.

Differential Revision: https://reviews.llvm.org/D125509

Decr return pc mid-stack when picking UnwindPlan row

When picking the UnwindPlan row to use to backtrace,
off of the zeroth frame, decrement the return pc so
we're in the address range of the call i

Decr return pc mid-stack when picking UnwindPlan row

When picking the UnwindPlan row to use to backtrace,
off of the zeroth frame, decrement the return pc so
we're in the address range of the call instruction.
If this is a noretrun function call, the instruction
at the "return address" is likely an entirely different
basic block with possibly very different unwind rules,
and this can cause the backtrace to be incorrect.

Differential Revision: https://reviews.llvm.org/D124957
rdar://84651805

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[lldb] Refactor DataBuffer so we can map files as read-only

Currently, all data buffers are assumed to be writable. This is a
problem on macOS where it's not allowed to load unsigned binaries in
mem

[lldb] Refactor DataBuffer so we can map files as read-only

Currently, all data buffers are assumed to be writable. This is a
problem on macOS where it's not allowed to load unsigned binaries in
memory as writable. To be more precise, MAP_RESILIENT_CODESIGN and
MAP_RESILIENT_MEDIA need to be set for mapped (unsigned) binaries on our
platform.

Binaries are mapped through FileSystem::CreateDataBuffer which returns a
DataBufferLLVM. The latter is backed by a llvm::WritableMemoryBuffer
because every DataBuffer in LLDB is considered to be writable. In order
to use a read-only llvm::MemoryBuffer I had to split our abstraction
around it.

This patch distinguishes between a DataBuffer (read-only) and
WritableDataBuffer (read-write) and updates LLDB to use the appropriate
one.

rdar://74890607

Differential revision: https://reviews.llvm.org/D122856

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[lldb] Remove vasprintf windows-compat implementation

We already have a VASprintf function for this purpose, so I'm switching
the remaining few users to that.

[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

Remove redundant string initialization (NFC)

Identified with readability-redundant-string-init.

[lldb][AArch64] Add UnwindPlan for Linux sigreturn

This adds a specific unwind plan for AArch64 Linux sigreturn frames.
Previously we assumed that the fp would be valid here but it is not.

https://

[lldb][AArch64] Add UnwindPlan for Linux sigreturn

This adds a specific unwind plan for AArch64 Linux sigreturn frames.
Previously we assumed that the fp would be valid here but it is not.

https://github.com/torvalds/linux/blob/master/arch/arm64/kernel/vdso/sigreturn.S

On Ubuntu Bionic it happened to point to an old frame info which meant
you got what looked like a correct backtrace. On Focal, the info is
completely invalid. (probably due to some code shuffling in libc)

This adds an UnwindPlan that knows that the sp in a sigreturn frame
points to an rt_sigframe from which we can offset to get saved
sp and pc values to backtrace correctly.

Based on LibUnwind's change: https://reviews.llvm.org/D90898

A new test is added that sets all compares the frames from the initial
signal catch to the handler break. Ensuring that the stack/frame pointer,
function name and register values match.
(this test is AArch64 Linux specific because it's the only one
with a specific unwind plan for this situation)

Fixes https://bugs.llvm.org/show_bug.cgi?id=52165

Reviewed By: omjavaid, labath

Differential Revision: https://reviews.llvm.org/D112069

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[lldb] Fixup more code addresses

The Swift async task pointers are signed on arm64e and we need to fixup
the addresses in the CFA and DWARF expressions.

[lldb] Implement ABI::Fix{Code,Data}Address for AArch64

Implement FixCodeAddress and FixDataAddress for ABIMacOSX_arm64 and
ABISysV_arm64 and add missing calls to RegisterContextUnwind. We need
this

[lldb] Implement ABI::Fix{Code,Data}Address for AArch64

Implement FixCodeAddress and FixDataAddress for ABIMacOSX_arm64 and
ABISysV_arm64 and add missing calls to RegisterContextUnwind. We need
this to unwind on Apple Silicon where libraries like libSystem are
arm64e even when the program being debugged is arm64.

Differential revision: https://reviews.llvm.org/D100521

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LanguageRuntime for 0th frame unwind, simplify getting pc-for-symbolication

Add calls into LanguageRuntime when finding the unwind method to
use out of the 0th (currently executing) stack frame.

Al

LanguageRuntime for 0th frame unwind, simplify getting pc-for-symbolication

Add calls into LanguageRuntime when finding the unwind method to
use out of the 0th (currently executing) stack frame.

Allow for the LanguageRuntimes to indicate if this stack frames
should be treated like a zeroth-frame -- symbolication should be
done based on the saved pc address, not decremented like normal ABI
function calls.

Add methods to RegisterContext and StackFrame to get a pc value
suitable for symbolication, to reduce the number of places in lldb
where we decrement the saved pc values before symbolication.

<rdar://problem/70398009>
Differential Revision: https://reviews.llvm.org/D97644

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LanguageRuntime can provide an UnwindPlan for special occasions

Add a facility in the LanguageRuntime to provide a special
UnwindPlan based on the register values in a RegisterContext,
instead of us

LanguageRuntime can provide an UnwindPlan for special occasions

Add a facility in the LanguageRuntime to provide a special
UnwindPlan based on the register values in a RegisterContext,
instead of using the return-pc to find a function and use its
normal UnwindPlans.

Needed when the runtime has special stack frames that we want
to show the user, but aren't actually on the real stack.
Specifically for Swift asynchronous functions.

With feedback from Greg Clayton, Jonas Devlieghere, Dave Lee

<rdar://problem/70398009>

Differential Revision: https://reviews.llvm.org/D96839

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Add a new Row setting to mark all un-declared regs as Undefined

Add a new state for UnwindPlan::Row which indicates that any
register not listed is not defined, and should not be found in
stack fram

Add a new Row setting to mark all un-declared regs as Undefined

Add a new state for UnwindPlan::Row which indicates that any
register not listed is not defined, and should not be found in
stack frames newer than this one and passed up the stack. Mostly
intended for use with architectural default unwind plans that are
used for jitted stack frames, where we have no unwind information
or start address. lldb has no way to tell if registers were
spilled in the jitted frame & overwritten, so passing register
values up the stack is not safe to show the user.

Architectural default unwind plans are also used as a fast unwind
plan on x86_64 in particular, and are used as the fallback unwind
plans when lldb thinks it may be able to work around a problem
which causes the unwinder to stop walking the stack early.

For fast unwind plans, when we don't find a register location in
the arch default unwind plan, we fall back to computing & using
the full unwind plan. One small part of this patch is to know that
a register marked as Undefined in the fast unwind plan is a special
case, and we should continue on to the full unwind plan to find what
the real unwind rule is for this register.

Differential Revision: https://reviews.llvm.org/D96829
<rdar://problem/70398009>

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Make the error condition in Value::ValueType explicit (NFC)

The comment for ValueType claims that all values <1 are errors, but
not all switch statements take this into account. This patch
introduce

Make the error condition in Value::ValueType explicit (NFC)

The comment for ValueType claims that all values <1 are errors, but
not all switch statements take this into account. This patch
introduces an explicit Error case and deletes all default: cases, so
we get warned about incomplete switch coverage.

https://reviews.llvm.org/D96537

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[lldb] NFC: Fix trivial typo in comments, documents, and messages

Differential Revision: https://reviews.llvm.org/D77460

[lldb] Make UnwindLLDB a non-plugin

Summary:
This is the only real unwinder, and things have been this way for quite
a long time. At this point, the class has accumulated so many features
it is unli

[lldb] Make UnwindLLDB a non-plugin

Summary:
This is the only real unwinder, and things have been this way for quite
a long time. At this point, the class has accumulated so many features
it is unlikely that anyone will want to reimplement the whole thing.

The class is also fairly closely coupled (through UnwindPlans and
FuncUnwinders) with a lot of other lldb components that it is hard to
imagine a different unwinder implementation being substantially
different without reimplementing all of those.

The existing unwinding functionality is nonetheless fairly complex and
there is space for adding more structure to it, but I believe a more
worthwhile effort would be to take the existing UnwindLLDB class and try
to break it down and introduce extension/customization points, instead
of writing a brand new Unwind implementation.

Reviewers: jasonmolenda, JDevlieghere, xiaobai

Subscribers: mgorny, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D75848

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