Use the range-based overload of llvm::sort where possible

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D130403

Fix the encoding and decoding of UniqueCStringMap<T> objects when saved to cache files.

UniqueCStringMap<T> objects are a std::vector<UniqueCStringMap::Entry> objects where the Entry object contains

Fix the encoding and decoding of UniqueCStringMap<T> objects when saved to cache files.

UniqueCStringMap<T> objects are a std::vector<UniqueCStringMap::Entry> objects where the Entry object contains a ConstString + T. The values in the vector are sorted first by ConstString and then by the T value. ConstString objects are simply uniqued "const char *" values and when we compare we use the actual string pointer as the value we sort by. This caused a problem when we saved the symbol table name indexes and debug info indexes to disk in one process when they were sorted, and then loaded them into another process when decoding them from the cache files. Why? Because the order in which the ConstString objects were created are now completely different and the string pointers will no longer be sorted in the new process the cache was loaded into.

The unit tests created for the initial patch didn't catch the encoding and decoding issues of UniqueCStringMap<T> because they were happening in the same process and encoding and decoding would end up createing sorted UniqueCStringMap<T> objects due to the constant string pool being exactly the same.

This patch does the sort and also reserves the right amount of entries in the UniqueCStringMap::m_map prior to adding them all to avoid doing multiple allocations.

Added a unit test that loads an object file from yaml, and then I created a cache file for the original file and removed the cache file's signature mod time check since we will generate an object file from the YAML, and use that as the object file for the Symtab object. Then we load the cache data from the array of symtab cache bytes so that the ConstString "const char *" values will not match the current process, and verify we can lookup the 4 names from the object file in the symbol table.

Differential Revision: https://reviews.llvm.org/D124572

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[lldb] Rename DemangleWithRichManglingInfo to GetRichManglingInfo (NFC)

This addresses Pavel's comment from D118814.

[lldb] Don't construct the demangled strings while indexing the symbol table

The symbol table needs to demangle all symbol names when building its
index. However, this doesn't require the full mangl

[lldb] Don't construct the demangled strings while indexing the symbol table

The symbol table needs to demangle all symbol names when building its
index. However, this doesn't require the full mangled name: we only need
the base name and the function declaration context. Currently, we always
construct the demangled string during indexing and cache it in the
string pool as a way to speed up future lookups.

Constructing the demangled string is by far the most expensive step of
the demangling process, because the output string can be exponentially
larger than the input and unless you're dumping the symbol table, many
of those demangled names will not be needed again.

This patch avoids constructing the full demangled string when we can
partially demangle. This speeds up indexing and reduces memory usage.

I gathered some numbers by attaching to Slack:

Before
------

Memory usage: 280MB
Benchmark 1: ./bin/lldb -n Slack -o quit
Time (mean ± σ): 4.829 s ± 0.518 s [User: 4.012 s, System: 0.208 s]
Range (min … max): 4.624 s … 6.294 s 10 runs

After
-----

Memory usage: 189MB
Benchmark 1: ./bin/lldb -n Slack -o quit
Time (mean ± σ): 4.182 s ± 0.025 s [User: 3.536 s, System: 0.192 s]
Range (min … max): 4.152 s … 4.233 s 10 runs

Differential revision: https://reviews.llvm.org/D118814

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[lldb] Improve RichManglingContext ergonomics (NFC)

Have the different ::Parse.* methods return the demangled string
directly instead of having to go through ::GetBufferRef.

Differential revision:

[lldb] Improve RichManglingContext ergonomics (NFC)

Have the different ::Parse.* methods return the demangled string
directly instead of having to go through ::GetBufferRef.

Differential revision: https://reviews.llvm.org/D118953

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Cache the manual DWARF index out to the LLDB cache directory when the LLDB index cache is enabled.

This patch add the ability to cache the manual DWARF indexing results to disk for faster subsequent

Cache the manual DWARF index out to the LLDB cache directory when the LLDB index cache is enabled.

This patch add the ability to cache the manual DWARF indexing results to disk for faster subsequent debug sessions. Manual DWARF indexing is time consuming and causes all DWARF to be fully parsed and indexed each time you debug a binary that doesn't have an acceptable accelerator table. Acceptable accelerator tables include .debug_names in DWARF5 or Apple accelerator tables.

This patch breaks up testing by testing all of the encoding and decoding of required C++ objects in a gtest unit test, and then has a test to verify the debug info cache is generated correctly.

This patch also adds the ability to track when a symbol table or DWARF index is loaded or saved to the cache in the "statistics dump" command. This is essential to know in statistics as it can help explain why a debug session was slower or faster than expected.

Reviewed By: labath, wallace

Differential Revision: https://reviews.llvm.org/D115951

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Added the ability to cache the finalized symbol tables subsequent debug sessions to start faster.

This is an updated version of the https://reviews.llvm.org/D113789 patch with the following changes:

Added the ability to cache the finalized symbol tables subsequent debug sessions to start faster.

This is an updated version of the https://reviews.llvm.org/D113789 patch with the following changes:
- We no longer modify modification times of the cache files
- Use LLVM caching and cache pruning instead of making a new cache mechanism (See DataFileCache.h/.cpp)
- Add signature to start of each file since we are not using modification times so we can tell when caches are stale and remove and re-create the cache file as files are changed
- Add settings to control the cache size, disk percentage and expiration in days to keep cache size under control

This patch enables symbol tables to be cached in the LLDB index cache directory. All cache files are in a single directory and the files use unique names to ensure that files from the same path will re-use the same file as files get modified. This means as files change, their cache files will be deleted and updated. The modification time of each of the cache files is not modified so that access based pruning of the cache can be implemented.

The symbol table cache files start with a signature that uniquely identifies a file on disk and contains one or more of the following items:
- object file UUID if available
- object file mod time if available
- object name for BSD archive .o files that are in .a files if available

If none of these signature items are available, then the file will not be cached. This keeps temporary object files from expressions from being cached.

When the cache files are loaded on subsequent debug sessions, the signature is compare and if the file has been modified (uuid changes, mod time changes, or object file mod time changes) then the cache file is deleted and re-created.

Module caching must be enabled by the user before this can be used:

symbols.enable-lldb-index-cache (boolean) = false

(lldb) settings set symbols.enable-lldb-index-cache true

There is also a setting that allows the user to specify a module cache directory that defaults to a directory that defaults to being next to the symbols.clang-modules-cache-path directory in a temp directory:

(lldb) settings show symbols.lldb-index-cache-path
/var/folders/9p/472sr0c55l9b20x2zg36b91h0000gn/C/lldb/IndexCache

If this setting is enabled, the finalized symbol tables will be serialized and saved to disc so they can be quickly loaded next time you debug.

Each module can cache one or more files in the index cache directory. The cache file names must be unique to a file on disk and its architecture and object name for .o files in BSD archives. This allows universal mach-o files to support caching multuple architectures in the same module cache directory. Making the file based on the this info allows this cache file to be deleted and replaced when the file gets updated on disk. This keeps the cache from growing over time during the compile/edit/debug cycle and prevents out of space issues.

If the cache is enabled, the symbol table will be loaded from the cache the next time you debug if the module has not changed.

The cache also has settings to control the size of the cache on disk. Each time LLDB starts up with the index cache enable, the cache will be pruned to ensure it stays within the user defined settings:

(lldb) settings set symbols.lldb-index-cache-expiration-days <days>

A value of zero will disable cache files from expiring when the cache is pruned. The default value is 7 currently.

(lldb) settings set symbols.lldb-index-cache-max-byte-size <size>

A value of zero will disable pruning based on a total byte size. The default value is zero currently.
(lldb) settings set symbols.lldb-index-cache-max-percent <percentage-of-disk-space>

A value of 100 will allow the disc to be filled to the max, a value of zero will disable percentage pruning. The default value is zero.

Reviewed By: labath, wallace

Differential Revision: https://reviews.llvm.org/D115324

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[lldb] Remove some trivial scoped timers

While profiling lldb (from swift/llvm-project), these timers were noticed to be short lived and high firing, and so they add noise more than value.

The data

[lldb] Remove some trivial scoped timers

While profiling lldb (from swift/llvm-project), these timers were noticed to be short lived and high firing, and so they add noise more than value.

The data points I recorded are:

`FindTypes_Impl`: 49,646 calls, 812ns avg, 40.33ms total
`AppendSymbolIndexesWithName`: 36,229 calls, 913ns avg, 33.09ms total
`FindAllSymbolsWithNameAndType`: 36,229 calls, 1.93µs avg, 70.05ms total
`FindSymbolsWithNameAndType`: 23,263 calls, 3.09µs avg, 71.88ms total

Differential Revision: https://reviews.llvm.org/D115182

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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.

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] Add support for demangling D symbols

This is part of https://github.com/dlang/projects/issues/81 .

This patch enables support for D programming language demangler by using a
pretty printed s

[lldb] Add support for demangling D symbols

This is part of https://github.com/dlang/projects/issues/81 .

This patch enables support for D programming language demangler by using a
pretty printed stacktrace with demangled D symbols, when present.

Signed-off-by: Luís Ferreira <[email protected]>

Reviewed By: JDevlieghere, teemperor

Differential Revision: https://reviews.llvm.org/D110578

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Support looking up absolute symbols

The Swift stdlib uses absolute symbols in the dylib to communicate
feature flags to the process. LLDB's expression evaluator needs to be
able to find them. This w

Support looking up absolute symbols

The Swift stdlib uses absolute symbols in the dylib to communicate
feature flags to the process. LLDB's expression evaluator needs to be
able to find them. This wires up absolute symbols so they show up in
the symtab lookup command, which is also all that's needed for them to
be visible to the expression evaluator JIT.

rdar://85093828

Differential Revision: https://reviews.llvm.org/D113445

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Add modules stats into the "statistics dump" command.

The new module stats adds the ability to measure the time it takes to parse and index the symbol tables for each module, and reports modules sta

Add modules stats into the "statistics dump" command.

The new module stats adds the ability to measure the time it takes to parse and index the symbol tables for each module, and reports modules statistics in the output of "statistics dump" along with the path, UUID and triple of the module. The time it takes to parse and index the symbol tables are also aggregated into new top level key/value pairs at the target level.

Differential Revision: https://reviews.llvm.org/D112279

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Create synthetic symbol names on demand to improve memory consumption and startup times.

This is a resubmission of https://reviews.llvm.org/D105160 after fixing testing issues.

This fix was created

Create synthetic symbol names on demand to improve memory consumption and startup times.

This is a resubmission of https://reviews.llvm.org/D105160 after fixing testing issues.

This fix was created after profiling the target creation of a large C/C++/ObjC application that contained almost 4,000,000 redacted symbol names. The symbol table parsing code was creating names for each of these synthetic symbols and adding them to the name indexes. The code was also adding the object file basename to the end of the symbol name which doesn't allow symbols from different shared libraries to share the names in the constant string pool.

Prior to this fix this was creating 180MB of "___lldb_unnamed_symbol" symbol names and was taking a long time to generate each name, add them to the string pool and then add each of these names to the name index.

This patch fixes the issue by:

not adding a name to synthetic symbols at creation time, and allows name to be dynamically generated when accessed
doesn't add synthetic symbol names to the name indexes, but catches this special case as name lookup time. Users won't typically set breakpoints or lookup these synthetic names, but support was added to do the lookup in case it does happen
removes the object file baseanme from the generated names to allow the names to be shared in the constant string pool
Prior to this fix the startup times for a large application was:
12.5 seconds (cold file caches)
8.5 seconds (warm file caches)

After this fix:
9.7 seconds (cold file caches)
5.7 seconds (warm file caches)

The names of the symbols are auto generated by appending the symbol's UserID to the end of the "___lldb_unnamed_symbol" string and is only done when the name is requested from a synthetic symbol if it has no name.

Differential Revision: https://reviews.llvm.org/D106837

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Revert "Create synthetic symbol names on demand to improve memory consumption and startup times."

This reverts commit c8164d0276b97679e80db01adc860271ab4a5d11 and
43f6dad2344247976d5777f56a1fc29e39c

Revert "Create synthetic symbol names on demand to improve memory consumption and startup times."

This reverts commit c8164d0276b97679e80db01adc860271ab4a5d11 and
43f6dad2344247976d5777f56a1fc29e39c6c717 because it breaks
TestDyldTrieSymbols.py on GreenDragon.

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[lldb] Replace default bodies of special member functions with = default;

Replace default bodies of special member functions with = default;

$ run-clang-tidy.py -header-filter='lldb' -checks='-*,mo

[lldb] Replace default bodies of special member functions with = default;

Replace default bodies of special member functions with = default;

$ run-clang-tidy.py -header-filter='lldb' -checks='-*,modernize-use-equals-default' -fix ,

https://clang.llvm.org/extra/clang-tidy/checks/modernize-use-equals-default.html

Differential revision: https://reviews.llvm.org/D104041

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Fix buildbot compile error for https://reviews.llvm.org/D105160.

Create synthetic symbol names on demand to improve memory consumption and startup times.

This fix was created after profiling the target creation of a large C/C++/ObjC application that contained alm

Create synthetic symbol names on demand to improve memory consumption and startup times.

This fix was created after profiling the target creation of a large C/C++/ObjC application that contained almost 4,000,000 redacted symbol names. The symbol table parsing code was creating names for each of these synthetic symbols and adding them to the name indexes. The code was also adding the object file basename to the end of the symbol name which doesn't allow symbols from different shared libraries to share the names in the constant string pool.

Prior to this fix this was creating 180MB of "___lldb_unnamed_symbol" symbol names and was taking a long time to generate each name, add them to the string pool and then add each of these names to the name index.

This patch fixes the issue by:
- not adding a name to synthetic symbols at creation time, and allows name to be dynamically generated when accessed
- doesn't add synthetic symbol names to the name indexes, but catches this special case as name lookup time. Users won't typically set breakpoints or lookup these synthetic names, but support was added to do the lookup in case it does happen
- removes the object file baseanme from the generated names to allow the names to be shared in the constant string pool

Prior to this fix the startup times for a large application was:
12.5 seconds (cold file caches)
8.5 seconds (warm file caches)

After this fix:
9.7 seconds (cold file caches)
5.7 seconds (warm file caches)

The names of the symbols are auto generated by appending the symbol's UserID to the end of the "___lldb_unnamed_symbol" string and is only done when the name is requested from a synthetic symbol if it has no name.

Differential Revision: https://reviews.llvm.org/D105160

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Revert D104488 and friends since it broke the windows bot

Reverts commits:
"Fix failing tests after https://reviews.llvm.org/D104488."
"Fix buildbot failure after https://reviews.llvm.org/D104488."

Revert D104488 and friends since it broke the windows bot

Reverts commits:
"Fix failing tests after https://reviews.llvm.org/D104488."
"Fix buildbot failure after https://reviews.llvm.org/D104488."
"Create synthetic symbol names on demand to improve memory consumption and startup times."

This series of commits broke the windows lldb bot and then failed to fix all of the failing tests.

show more ...

Fix buildbot failure after https://reviews.llvm.org/D104488.

Create synthetic symbol names on demand to improve memory consumption and startup times.

This fix was created after profiling the target creation of a large C/C++/ObjC application that contained alm

Create synthetic symbol names on demand to improve memory consumption and startup times.

This fix was created after profiling the target creation of a large C/C++/ObjC application that contained almost 4,000,000 redacted symbol names. The symbol table parsing code was creating names for each of these synthetic symbols and adding them to the name indexes. The code was also adding the object file basename to the end of the symbol name which doesn't allow symbols from different shared libraries to share the names in the constant string pool.

Prior to this fix this was creating 180MB of "___lldb_unnamed_symbol" symbol names and was taking a long time to generate each name, add them to the string pool and then add each of these names to the name index.

This patch fixes the issue by:
- not adding a name to synthetic symbols at creation time, and allows name to be dynamically generated when accessed
- doesn't add synthetic symbol names to the name indexes, but catches this special case as name lookup time. Users won't typically set breakpoints or lookup these synthetic names, but support was added to do the lookup in case it does happen
- removes the object file baseanme from the generated names to allow the names to be shared in the constant string pool

Prior to this fix the startup times for a large application was:
12.5 seconds (cold file caches)
8.5 seconds (warm file caches)

After this fix:
9.7 seconds (cold file caches)
5.7 seconds (warm file caches)

The names of the symbols are auto generated by appending the symbol's UserID to the end of the "___lldb_unnamed_symbol" string and is only done when the name is requested from a synthetic symbol if it has no name.

Differential Revision: https://reviews.llvm.org/D104488

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[lldb] Decouple ObjCLanguage from Symtab

We can extend/modify `GetMethodNameVariants` to suit our purposes here.
What symtab is looking for is alternate names we may want to use to
search for a spec

[lldb] Decouple ObjCLanguage from Symtab

We can extend/modify `GetMethodNameVariants` to suit our purposes here.
What symtab is looking for is alternate names we may want to use to
search for a specific symbol, and asking for variants of a name makes
the most sense here.

Differential Revision: https://reviews.llvm.org/D104067

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[lldb] Enable Rust v0 symbol demangling

Rust's v0 name mangling scheme [1] is easy to disambiguate from other
name mangling schemes because symbols always start with `_R`. The llvm
Demangle library

[lldb] Enable Rust v0 symbol demangling

Rust's v0 name mangling scheme [1] is easy to disambiguate from other
name mangling schemes because symbols always start with `_R`. The llvm
Demangle library supports demangling the Rust v0 scheme. Use it to
demangle Rust symbols.

Added unit tests that check simple symbols. Ran LLDB built with this
patch to debug some Rust programs compiled with the v0 name mangling
scheme. Confirmed symbol names were demangled as expected.

Note: enabling the new name mangling scheme requires a nightly
toolchain:

```
$ cat main.rs
fn main() {
println!("Hello world!");
}
$ $(rustup which --toolchain nightly rustc) -Z symbol-mangling-version=v0 main.rs -g
$ /home/asm/hacking/llvm/build/bin/lldb ./main --one-line 'b main.rs:2'
(lldb) target create "./main"
Current executable set to '/home/asm/hacking/llvm/rust/main' (x86_64).
(lldb) b main.rs:2
Breakpoint 1: where = main`main::main + 4 at main.rs:2:5, address = 0x00000000000076a4
(lldb) r
Process 948449 launched: '/home/asm/hacking/llvm/rust/main' (x86_64)
warning: (x86_64) /lib64/libgcc_s.so.1 No LZMA support found for reading .gnu_debugdata section
Process 948449 stopped
* thread #1, name = 'main', stop reason = breakpoint 1.1
frame #0: 0x000055555555b6a4 main`main::main at main.rs:2:5
1 fn main() {
-> 2 println!("Hello world!");
3 }
(lldb) bt
error: need to add support for DW_TAG_base_type '()' encoded with DW_ATE = 0x7, bit_size = 0
* thread #1, name = 'main', stop reason = breakpoint 1.1
* frame #0: 0x000055555555b6a4 main`main::main at main.rs:2:5
frame #1: 0x000055555555b78b main`<fn() as core::ops::function::FnOnce<()>>::call_once((null)=(main`main::main at main.rs:1), (null)=<unavailable>) at function.rs:227:5
frame #2: 0x000055555555b66e main`std::sys_common::backtrace::__rust_begin_short_backtrace::<fn(), ()>(f=(main`main::main at main.rs:1)) at backtrace.rs:125:18
frame #3: 0x000055555555b851 main`std::rt::lang_start::<()>::{closure#0} at rt.rs:49:18
frame #4: 0x000055555556c9f9 main`std::rt::lang_start_internal::hc51399759a90501a [inlined] core::ops::function::impls::_$LT$impl$u20$core..ops..function..FnOnce$LT$A$GT$$u20$for$u20$$RF$F$GT$::call_once::h04259e4a34d07c2f at function.rs:259:13
frame #5: 0x000055555556c9f2 main`std::rt::lang_start_internal::hc51399759a90501a [inlined] std::panicking::try::do_call::hb8da45704d5cfbbf at panicking.rs:401:40
frame #6: 0x000055555556c9f2 main`std::rt::lang_start_internal::hc51399759a90501a [inlined] std::panicking::try::h4beadc19a78fec52 at panicking.rs:365:19
frame #7: 0x000055555556c9f2 main`std::rt::lang_start_internal::hc51399759a90501a [inlined] std::panic::catch_unwind::hc58016cd36ba81a4 at panic.rs:433:14
frame #8: 0x000055555556c9f2 main`std::rt::lang_start_internal::hc51399759a90501a at rt.rs:34:21
frame #9: 0x000055555555b830 main`std::rt::lang_start::<()>(main=(main`main::main at main.rs:1), argc=1, argv=0x00007fffffffcb18) at rt.rs:48:5
frame #10: 0x000055555555b6fc main`main + 28
frame #11: 0x00007ffff73f2493 libc.so.6`__libc_start_main + 243
frame #12: 0x000055555555b59e main`_start + 46
(lldb)
```

[1]: https://github.com/rust-lang/rust/issues/60705

Reviewed By: clayborg, teemperor

Differential Revision: https://reviews.llvm.org/D104054

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[lldb][NFC] Refactor name to index maps in Symtab

The various maps in Symtab lead to some repetative code. This should
improve the situation somewhat.

Differential Revision: https://reviews.llvm.or

[lldb][NFC] Refactor name to index maps in Symtab

The various maps in Symtab lead to some repetative code. This should
improve the situation somewhat.

Differential Revision: https://reviews.llvm.org/D103652

show more ...