Commit Graph

27 Commits

Author SHA1 Message Date
Kazu Hirata 343523d040 [lldb] Use std::nullopt instead of None (NFC)
This patch mechanically replaces None with std::nullopt where the
compiler would warn if None were deprecated.  The intent is to reduce
the amount of manual work required in migrating from Optional to
std::optional.

This is part of an effort to migrate from llvm::Optional to
std::optional:

https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
2022-12-04 16:51:25 -08:00
Derek Schuff 2ae385e560 [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
2022-06-07 12:05:23 -07:00
Jonas Devlieghere f2ea125ea0
[lldb] Change CreateMemoryInstance to take a WritableDataBuffer
Change the CreateMemoryInstance interface to take a WritableDataBuffer.

Differential revision: https://reviews.llvm.org/D123073
2022-04-05 13:46:41 -07:00
Jonas Devlieghere fc54427e76
[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
2022-04-05 13:46:37 -07:00
Jonas Devlieghere c69307e5ee
[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
2022-04-04 09:24:24 -07:00
Pavel Labath c34698a811 [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.
2022-02-03 14:47:01 +01:00
Pavel Labath a007a6d844 [lldb] Convert "LLDB" log channel to the new API 2022-02-02 14:13:08 +01:00
Greg Clayton 7e6df41f65 [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
2021-11-30 13:54:32 -08:00
Greg Clayton a68ccda203 Revert "[NFC] Refactor symbol table parsing."
This reverts commit 951b107eed.

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.
2021-11-17 18:07:28 -08:00
Greg Clayton 951b107eed [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
2021-11-17 15:14:01 -08:00
Pavel Labath 2ace1e5753 [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
2021-10-21 12:58:45 +02:00
Pavel Labath a3939e159f [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
2021-10-18 10:14:42 +02:00
Pavel Labath b03126768a [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
2021-09-13 10:29:00 +02:00
Heejin Ahn 1d891d44f3 [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
2021-06-17 20:34:19 -07:00
Philip Pfaffe 7ad54d1938 [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
2021-01-14 08:45:02 +01:00
Pavel Labath 3a16829748 [lldb] Switch Section-dumping code to raw_ostream
Also, add a basic test for dumping sections.
2020-05-14 11:59:18 +02:00
Jonas Devlieghere cdc514e4c6 [lldb] Update header guards to be consistent and compliant with LLVM (NFC)
LLDB has a few different styles of header guards and they're not very
consistent because things get moved around or copy/pasted. This patch
unifies the header guards across LLDB and converts everything to match
LLVM's style.

Differential revision: https://reviews.llvm.org/D74743
2020-02-17 23:15:40 -08:00
Paolo Severini c1121908aa [LLDB] Add DynamicLoaderWasmDYLD plugin for WebAssembly debugging
Add a dynamic loader plug-in class for WebAssembly modules.

Differential Revision: https://reviews.llvm.org/D72751
2020-02-17 12:42:23 +01:00
Jonas Devlieghere bba9ba8d95 [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.
2020-02-14 09:58:24 -08:00
Martin Storsjö 6115bd9ba2 [LLDB] Fix GCC warnings about extra semicolons. NFC. 2020-02-10 11:20:44 +02:00
Jonas Devlieghere fbb4d1e43d [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
2020-02-07 15:28:27 -08:00
Pavel Labath 40efa65de8 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:
014ea93376,
f5f70d1c8f.
4697e701b8.
5c15e8e682.
3ec28da6d6.
2020-02-05 16:22:19 -08:00
Paolo Severini 3ec28da6d6 [LLDB] Add DynamicLoaderWasmDYLD plugin for WebAssembly debugging
Add a dynamic loader plug-in class for WebAssembly modules.

Differential Revision: https://reviews.llvm.org/D72751
2020-02-05 14:49:36 -08:00
Derek Schuff d34e4152e3 [LLDB] Convert Plugins/ObjectFile/wasm/ObjectFileWasm.h to unix line endings 2020-01-16 09:38:37 -08:00
Paolo Severini 9b3254dbf9 [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
2020-01-16 09:36:17 -08:00
Jim Ingham cd9e5c3230 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.
2020-01-15 18:13:44 -08:00
Paolo Severini 4bafceced6 [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
2020-01-15 16:25:35 -08:00