[WebAssembly] Add WASM_SEC_LAST_KNOWN to BinaryFormat section types list [NFC]

There are 3 places where we were using WASM_SEC_TAG as the "last" known
section type, which requires updating (or leave

[WebAssembly] Add WASM_SEC_LAST_KNOWN to BinaryFormat section types list [NFC]

There are 3 places where we were using WASM_SEC_TAG as the "last" known
section type, which requires updating (or leaves a bug) when a new known
section type is added. Instead add a "last type" to the enum for this
purpose.

Differential Revision: https://reviews.llvm.org/D127164

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[lldb] Change CreateMemoryInstance to take a WritableDataBuffer

Change the CreateMemoryInstance interface to take a WritableDataBuffer.

Differential revision: https://reviews.llvm.org/D123073

[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] Prevent object file plugins from changing the data buffer

The current design allows that the object file contents could be mapped
by one object file plugin and then used by another. Presumabl

[lldb] Prevent object file plugins from changing the data buffer

The current design allows that the object file contents could be mapped
by one object file plugin and then used by another. Presumably the idea
here was to avoid mapping the same file twice.

This becomes an issue when one object file plugin wants to map the file
differently from the others. For example, ObjectFileELF needs to map its
memory as writable while others likeObjectFileMachO needs it to be
mapped read-only.

This patch prevents plugins from changing the buffer by passing them is
by value rather than by reference.

Differential revision: https://reviews.llvm.org/D122944

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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

[NFC] Refactor symbol table parsing.

Symbol table parsing has evolved over the years and many plug-ins contained duplicate code in the ObjectFile::GetSymtab() that used to be pure virtual. With this

[NFC] Refactor symbol table parsing.

Symbol table parsing has evolved over the years and many plug-ins contained duplicate code in the ObjectFile::GetSymtab() that used to be pure virtual. With this change, the "Symbtab *ObjectFile::GetSymtab()" is no longer virtual and will end up calling a new "void ObjectFile::ParseSymtab(Symtab &symtab)" pure virtual function to actually do the parsing. This helps centralize the code for parsing the symbol table and allows the ObjectFile base class to do all of the common work, like taking the necessary locks and creating the symbol table object itself. Plug-ins now just need to parse when they are asked to parse as the ParseSymtab function will only get called once.

This is a retry of the original patch https://reviews.llvm.org/D113965 which was reverted. There was a deadlock in the Manual DWARF indexing code during symbol preloading where the module was asked on the main thread to preload its symbols, and this would in turn cause the DWARF manual indexing to use a thread pool to index all of the compile units, and if there were relocations on the debug information sections, these threads could ask the ObjectFile to load section contents, which could cause a call to ObjectFileELF::RelocateSection() which would ask for the symbol table from the module and it would deadlock. We can't lock the module in ObjectFile::GetSymtab(), so the solution I am using is to use a llvm::once_flag to create the symbol table object once and then lock the Symtab object. Since all APIs on the symbol table use this lock, this will prevent anyone from using the symbol table before it is parsed and finalized and will avoid the deadlock I mentioned. ObjectFileELF::GetSymtab() was never locking the module lock before and would put off creating the symbol table until somewhere inside ObjectFileELF::GetSymtab(). Now we create it one time inside of the ObjectFile::GetSymtab() and immediately lock it which should be safe enough. This avoids the deadlocks and still provides safety.

Differential Revision: https://reviews.llvm.org/D114288

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Revert "[NFC] Refactor symbol table parsing."

This reverts commit 951b107eedab1829f18049443f03339dbb0db165.

Buildbots were failing, there is a deadlock in /Users/gclayton/Documents/src/llvm/clean/l

Revert "[NFC] Refactor symbol table parsing."

This reverts commit 951b107eedab1829f18049443f03339dbb0db165.

Buildbots were failing, there is a deadlock in /Users/gclayton/Documents/src/llvm/clean/llvm-project/lldb/test/Shell/SymbolFile/DWARF/DW_AT_range-DW_FORM_sec_offset.s when ELF files try to relocate things.

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[NFC] Refactor symbol table parsing.

Symbol table parsing has evolved over the years and many plug-ins contained duplicate code in the ObjectFile::GetSymtab() that used to be pure virtual. With this

[NFC] Refactor symbol table parsing.

Symbol table parsing has evolved over the years and many plug-ins contained duplicate code in the ObjectFile::GetSymtab() that used to be pure virtual. With this change, the "Symbtab *ObjectFile::GetSymtab()" is no longer virtual and will end up calling a new "void ObjectFile::ParseSymtab(Symtab &symtab)" pure virtual function to actually do the parsing. This helps centralize the code for parsing the symbol table and allows the ObjectFile base class to do all of the common work, like taking the necessary locks and creating the symbol table object itself. Plug-ins now just need to parse when they are asked to parse as the ParseSymtab function will only get called once.

Differential Revision: https://reviews.llvm.org/D113965

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[lldb] Remove ConstString from GetPluginNameStatic of some plugins

This patch deals with ObjectFile, ObjectContainer and OperatingSystem
plugins. I'll convert the other types in separate patches.

I

[lldb] Remove ConstString from GetPluginNameStatic of some plugins

This patch deals with ObjectFile, ObjectContainer and OperatingSystem
plugins. I'll convert the other types in separate patches.

In order to enable piecemeal conversion, I am leaving some ConstStrings
in the lowest PluginManager layers. I'll convert those as the last step.

Differential Revision: https://reviews.llvm.org/D112061

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[WebAssembly] Rename event to tag

We recently decided to change 'event' to 'tag', and 'event section' to
'tag section', out of the rationale that the section contains a
generalized tag that referenc

[WebAssembly] Rename event to tag

We recently decided to change 'event' to 'tag', and 'event section' to
'tag section', out of the rationale that the section contains a
generalized tag that references a type, which may be used for something
other than exceptions, and the name 'event' can be confusing in the web
context.

See
- https://github.com/WebAssembly/exception-handling/issues/159#issuecomment-857910130
- https://github.com/WebAssembly/exception-handling/pull/161

Reviewed By: tlively

Differential Revision: https://reviews.llvm.org/D104423

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[lldb][wasm] Parse DWO section names

Mirror ELF section parsing to support DWARF section names for
debug fission.

Reviewed By: labath

Differential Revision: https://reviews.llvm.org/D93621

[lldb] Switch Section-dumping code to raw_ostream

Also, add a basic test for dumping sections.

[LLDB] Add DynamicLoaderWasmDYLD plugin for WebAssembly debugging

Add a dynamic loader plug-in class for WebAssembly modules.

Differential Revision: https://reviews.llvm.org/D72751

[lldb/Plugin] s/LLDB_PLUGIN/LLDB_PLUGIN_DEFINE/ (NFC)

Rename LLDB_PLUGIN to LLDB_PLUGIN_DEFINE as Pavel suggested in D73067 to
avoid name conflict.

[LLDB] Fix GCC warnings about extra semicolons. NFC.

[lldb/Plugins] Use external functions to (de)initialize plugins

This is a step towards making the initialize and terminate calls be
generated by CMake, which in turn is towards making it possible to

[lldb/Plugins] Use external functions to (de)initialize plugins

This is a step towards making the initialize and terminate calls be
generated by CMake, which in turn is towards making it possible to
disable plugins at configuration time.

Differential revision: https://reviews.llvm.org/D74245

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Revert "[LLDB] Add DynamicLoaderWasmDYLD plugin for WebAssembly debugging"

This patch has a couple of outstanding issues. The test is not python3
compatible, and it also seems to fail with python2 (

Revert "[LLDB] Add DynamicLoaderWasmDYLD plugin for WebAssembly debugging"

This patch has a couple of outstanding issues. The test is not python3
compatible, and it also seems to fail with python2 (at least under some
circumstances) due to an overambitious assertion.

This reverts the patch as well as subsequent fixup attempts:
014ea9337624fe20aca8892e73b6b3f741d8da9e,
f5f70d1c8fbf12249b4b9598f10a10f12d4db029.
4697e701b8cb40429818609814c7422e49b2ee07.
5c15e8e682e365b3a7fcf35200df79f3fb93b924.
3ec28da6d6430a00b46780555a87acd43fcab790.

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[LLDB] Add DynamicLoaderWasmDYLD plugin for WebAssembly debugging

Add a dynamic loader plug-in class for WebAssembly modules.

Differential Revision: https://reviews.llvm.org/D72751

[LLDB] Add SymbolVendorWasm plugin for WebAssembly debugging

Add plugin class SymbolVendorWasm, with the logic to manage debug symbols
for Wasm modules.

Reviewers: clayborg, labath, aprantl, sbc100

[LLDB] Add SymbolVendorWasm plugin for WebAssembly debugging

Add plugin class SymbolVendorWasm, with the logic to manage debug symbols
for Wasm modules.

Reviewers: clayborg, labath, aprantl, sbc100, teemperor

Reviewed By: labath

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D72650

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Fix the macos build after D71575.

size_t and uint64_t are spelled slightly differently on macOS, which was
causing the compiler to error out calling std::min - since the two types have
to be the sam

Fix the macos build after D71575.

size_t and uint64_t are spelled slightly differently on macOS, which was
causing the compiler to error out calling std::min - since the two types have
to be the same.

I fixed this by casting the uint64_t computation to a size_t. That's probably
not the cleanest solution, but it gets us back to building.

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[LLDB] Add ObjectFileWasm plugin for WebAssembly debugging

Summary:
This is the first in a series of patches to enable LLDB debugging of
WebAssembly targets.

Current versions of Clang emit (partial

[LLDB] Add ObjectFileWasm plugin for WebAssembly debugging

Summary:
This is the first in a series of patches to enable LLDB debugging of
WebAssembly targets.

Current versions of Clang emit (partial) DWARF debug information in WebAssembly
modules and we can leverage this debug information to give LLDB the ability to
do source-level debugging of Wasm code that runs in a WebAssembly engine.

A way to do this could be to use the remote debugging functionalities provided
by LLDB via the GDB-remote protocol. Remote debugging can indeed be useful not
only to connect a debugger to a process running on a remote machine, but also to
connect the debugger to a managed VM or script engine that runs locally,
provided that the engine implements a GDB-remote stub that offers the ability to
access the engine runtime internal state.

To make this work, the GDB-remote protocol would need to be extended with a few
Wasm-specific custom query commands, used to access aspects of the Wasm engine
state (like the Wasm memory, Wasm local and global variables, and so on).
Furthermore, the DWARF format would need to be enriched with a few Wasm-specific
extensions, here detailed: https://yurydelendik.github.io/webassembly-dwarf.

This CL introduce classes **ObjectFileWasm**, a file plugin to represent a Wasm
module loaded in a debuggee process. It knows how to parse Wasm modules and
store the Code section and the DWARF-specific sections.

Reviewers: jasonmolenda, clayborg, labath

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D71575

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