Small change to use (what I think is) a better practice -- we were using
the `m_indexed` bool member to make sure we called `Index()` once, but
we should just use `std::once`! This change shouldn't affect
functionality.
This change may also make concurrent access to `Index()` thread-safe,
though the ManualDWARFIndex API isn't completely thread-safe due to
`Decode()`. I'm not sure if ManualDWARFIndex was ever intended to be
thread-safe.
Test Plan:
`ninja check-lldb`
Tested basic debugging workflow of a couple of large projects I had
built. Basically:
```
(lldb) target create <project>
(lldb) b main
(lldb) r
(lldb) step
...
```
I A/B tested the performance of launching several modules with parallel
module loading and didn't observe any performance regressions.
---------
Co-authored-by: Tom Yang <toyang@fb.com>
Depends on:
* https://github.com/llvm/llvm-project/pull/165686
This patch ensures we make use of the `DW_AT_bit_size` on
`DW_TAG_base_type`s (which since
https://github.com/llvm/llvm-project/pull/164372 can exist on
`_BitInt`s) and adjusts `TypeSystemClang` to recognize `_BitInt`.
For DWARF from older versions of Clang that didn't emit a
`DW_AT_bit_size`, we would create `_BitInt`s using the byte-size. Not
sure we can do much better than that. But the situation beforehand
wasn't much better.
Before:
```
(lldb) v
(char) a = '\x01'
(unsigned char) b = '\x01'
(long) c = 2
(unsigned long) d = 2
```
After:
```
(lldb) v
(_BitInt(2)) a = 1
(unsigned _BitInt(2)) b = 1
(_BitInt(52)) c = 2
(unsigned _BitInt(52)) d = 2
```
Fixes https://github.com/llvm/llvm-project/issues/110273
Similar motivation to https://github.com/llvm/llvm-project/pull/165702.
It was unused in all callsites and inconsistent with other APIs like
`IsIntegerType` (which doesn't take a `count` parameter).
If we ever need a "how many elements does this type represent", we can
implement one with a new TypeSystem API that does exactly that.
Some callsites checked for `count == 1` previously, but I suspect what
they intended to do is check for whether it's a vector type or complex
type, before reading the FP register. I'm somewhat confident that's the
case because the `TypeSystemClang::GetTypeInfo` currently incorrectly
sets the integer and floating point bits for complex and vector types
(will fix separately). But some architectures might choose to pass
single-element vectors in scalar registers. I should probably changes
these to check the vector element size.
All the `count == 2 && is_complex` were redundant because `count == 2`
iff `is_complex == true`. So I just removed the count check there.
In #165604, a test was skipped on Windows, because the native PDB plugin
didn't set sizes on symbols. While the test isn't compiled with debug
info, it's linked with `-gdwarf`, causing a PDB to be created on
Windows. This PDB will only contain the public symbols (written by the
linker) and section information. The symbols themselves don't have a
size, however the DIA SDK sets a size for them.
It seems like, for these data symbols, the size given from DIA is the
distance to the next symbol (or the section end).
This PR implements the naive approach for the native plugin. The main
difference is in function/code symbols. There, DIA searches for a
corresponding `S_GPROC32` which have a "code size" that is sometimes
slightly smaller than the difference to the next symbol.
One (DWARF-spec compliant) exmample is:
https://github.com/llvm/llvm-project/pull/164372, where we attach a
`DW_AT_bit_size` to `_BitInt` types that can't be exactly described by a
byte-size.
This patch adds support for `DW_AT_bit_size` to `DWARFASTParserClang`
when parsing type tags.
Note, we don't use this bit-size yet, but will do so in follow-up
patches.
All PDB tests now pass when compiled without DIA on Windows, so they
pass with the native reader.
With this PR, the default reader changes to the native reader.
The plan is to eventually remove the DIA reader (see
https://discourse.llvm.org/t/rfc-removing-the-dia-pdb-plugin-from-lldb/87827
and #114906).
For now, DIA can be used by setting `plugin.symbol-file.pdb.reader` to
`dia` or by setting `LLDB_USE_NATIVE_PDB_READER=0` (mostly undocumented,
but used in tests).
[lldb][DWARFASTParserClang] Added a check for the specialization
existence
While debugging an application with incorrect dwarf information, where
DW_TAG_template_value_parameter was lost, I found that lldb does not
check that the corresponding specialization exists. As a result, at the
stage when ASTImporter works, the type is completed in such a way that
it inherits from itself. And during the calculation of layout, an
infinite recursion occurs. To catch this error, I added a corresponding
check
at the stage of restoring the type from dwarf information. I also added
a
trivial assert in clang to check that the class does not inherit from
itself.
When creating all types in a compilation unit, simple types (~>
primitive and pointer types) that were only used in function arguments
or return types weren't created as LLDB `Type`s.
With this PR, they're created when creating the function/method types.
This makes it possible to run the `SymbolFile/PDB/typedefs.test` with
both plugins.
This aligns the simple types created by the native plugin with the ones
from DIA as well as LLVM and the original cvdump.
- A few type names weren't handled when creating the LLDB `Type` name
(e.g. `short`)
- 64-bit integers were created as `(u)int64_t` and are now created as
`(unsigned) long long` (matches DIA)
- 128-bit integers (only supported by clang-cl) weren't created as types
(they have `SimpleTypeKind::(U)Int128Oct`)
- All complex types had the same name - now they have `_Complex
<float-type>`
Some types like `SimpleTypeKind::Float48` can't be tested because they
can't be created in C++.
Before this PR, the native PDB plugin would create the following LLDB
`Type` for `using SomeTypedef = long`:
```
Type{0x00002e03} , name = "SomeTypedef", size = 4, compiler_type = 0x000002becd8d8620 long
```
with this PR, the following is created:
```
Type{0x00002e03} , name = "SomeTypedef", size = 4, compiler_type = 0x0000024d6a7e3c90 typedef SomeTypedef
```
This matches the behavior of the DIA PDB plugin and works towards making
[`Shell/SymbolFile/PDB/typedefs.test`](https://github.com/llvm/llvm-project/blob/main/lldb/test/Shell/SymbolFile/PDB/typedefs.test)
pass with the native plugin.
I added a similar test to the `NativePDB` shell tests to capture the
current state, which doesn't quite match that of DIA yet. I'll add some
comments on what's missing on this PR, because I'm not fully sure what
the correct output would be.
Relands #149701 which was reverted in
185ae5cdc6
because it broke demangling of Itanium symbols on i386.
The last commit in this PR adds the fix for this (discussed in #160930).
On x86 environments, the prefix of `__cdecl` functions will now be
removed to match DWARF. I opened #161676 to discuss this for the other
calling conventions.
First time check was introduced in
`fa3ab4599d717feedbb83e08e7f654913942520b` to work around a debug-info
generation bug in Clang. This bug was fixed in Clang-4. The check has
since been adjusted (first in
`808ff186f6a6ba1fd38cc7e00697cd82f4afe540`, and then most recently in
`370db9c62910195e664e82dde6f0adb3e255a4fd`).
This check is getting quite convoluted, and all it does is turn an
`array[1]` into an `array[0]` type when it is deemed correct. At this
point the workaround probably never fires, apart from actually valid
codegen. This patch removes the special conditions and emits the error
specifically in those cases where we know the DWARF is malformed.
Added some shell tests for the error case.
GCC doesn't add DW_AT_data_member_location attributes to the
DW_TAG_member children of DW_TAG_union_type types. An error was being
emitted incorrectly for these cases fr om the DWARFASTParserClang. This
fixes that issue and adds a test.
Before, functions created using the NativePDB plugin would not know
about their mangled name. This showed when printing a stacktrace. There,
only the function name was shown. For
https://github.com/llvm/llvm-project/issues/143149, the mangled function
name is required to separate different parts.
This PR adds that name if available.
The Clang AST nodes also take in a mangled name, which was previously
unset. I don't think this unblocks anything further, because Clang can
mangle the function anyway.
If LLDB was built without the DIA SDK and the DIA reader is explicitly
requested (through `LLDB_USE_NATIVE_PDB_READER=0` or `settings set
plugin.symbol-file.pdb.reader dia`), LLDB should print a warning,
because it will use the native reader in any case
(https://github.com/llvm/llvm-project/pull/159769#discussion_r2367316980).
This PR adds the warning and a test when LLDB is not built with the SDK
on Windows. I don't think any builder runs this configuration, as there
are still five failing tests. I tested this locally with and without the
SDK.
When creating LLDB types from `LF_MODIFIER` records, the type name of
the modified type was used. This didn't include the modifiers
(`const`/`volatile`/`__unaligned`). With this PR, they're included.
The DIA plugin had a test for this. That test also assumed that function
types had a name. I removed that check here, because function/procedure
types themselves in PDB don't have a name:
```
0x1015 | LF_ARGLIST [size = 20, hash = 0xBCB6]
0x0074 (int): `int`
0x1013: `int* __restrict`
0x1014: `int& __restrict`
0x1016 | LF_PROCEDURE [size = 16, hash = 0x3F611]
return type = 0x0003 (void), # args = 3, param list = 0x1015
calling conv = cdecl, options = None
```
I assume DIA gets the name from the function symbol itself. In the
native plugin, that name isn't included and multiple functions with the
same signature will reuse one type, whereas DIA would create a new type
for each function. The
[Shell/SymbolFile/PDB/func-symbols.test](b29c7ded31/lldb/test/Shell/SymbolFile/PDB/func-symbols.test)
also relies on this.
This patch causes the various AST dump commands (`target modules dump
ast`/`target dump typesystem`) to be color-highlighted. I added a `bool
show_color` parameter to `SymbolFile::DumpClangAST` and
`TypeSystem::Dump`. In `TypeSystemClang` I temporarily sets the
`getShowColors` flag on the owned Clang AST (using an RAII helper) for
the duration of the AST dump. We use `Debugger::GetUseColors` to decide
whether to color the AST dump.
This relands changes in https://github.com/llvm/llvm-project/pull/155023
for adding a count of dwo errors and combine all the dwo related stats
into one struct.
The previous PR was reverted in
https://github.com/llvm/llvm-project/pull/156777 as the newly added unit
test `test_dwo_id_mismatch_error_stats` sometimes fails due to
inappropriate use of `glob.glob`.
This change modified the tests created in the former PR to collect and
modify the dwo files by there names instead of using index after
`glob.glob`. This will avoid the possible failure in these tests if the
order of dwo files changes.
[Original PR:
https://github.com/llvm/llvm-project/pull/155023](https://github.com/llvm/llvm-project/pull/155023)
## Testing
Ran unit tests
```
$ ./bin/llvm-lit /data/users/ziyiww/llvm-project/lldb/test/API/commands/statistics/basic/TestStats.py
./bin/llvm-lit /data/users/ziyiww/llvm-project/lldb/test/API/commands/statistics/basic/TestStats.py -v
-- Testing: 1 tests, 1 workers --
PASS: lldb-api :: commands/statistics/basic/TestStats.py (1 of 1)
Testing Time: 388.52s
Total Discovered Tests: 1
Passed: 1 (100.00%)
$ bin/lldb-dotest -p TestStats.py /data/users/ziyiww/llvm-project/lldb/test/API/commands/statistics/basic/
----------------------------------------------------------------------
Ran 27 tests in 386.302s
OK (skipped=3)
```
After parsing blocks in a function, the blocks should be marked as
parsed for them to be dumped (see
[Function::Dump](e6aefbec78/lldb/source/Symbol/Function.cpp (L446-L447))).
As explained in
https://github.com/llvm/llvm-project/issues/114906#issuecomment-3255016266,
this happens (accidentally?) in the DIA plugin when parsing variables,
because it calls `function.GetBlock(can_create=true)` which marks blocks
as parsed. In the native plugin, this was never called, so blocks and
variables were never included in the `lldb-test symbols` output.
The `variables.test` for the DIA plugin tests this. One difference
between the plugins is how they specify the location of local variables.
This causes the output of the native plugin to be two lines per
variable, whereas the DIA plugin has one line:
```
(native):
000002C4B7593020: Variable{0x1c800001}, name = "var_arg1", type = {0000000000000744} 0x000002C4B6CA7900 (int), scope = parameter, location = 0x00000000:
[0x000000014000102c, 0x000000014000103e): DW_OP_breg7 RSP+8
```
```
(DIA):
000002778C827EE0: Variable{0x0000001b}, name = "var_arg1", type = {0000000000000005} 0x000002778C1FBAB0 (int), scope = parameter, decl = VariablesTest.cpp:32, location = DW_OP_breg7 RSP+8
```
In the test, I filtered lines starting with spaces followed by `[0x`, so
we can still use `CHECK-NEXT`.
---
Another difference between the plugins is that DIA marks the `this`
pointer as artificial (equivalent to DWARF). This is done if a
variable's object kind is `ObjectPtr`
([source](ab898f32c6/lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.cpp (L1050))).
As far as I know, there isn't anything in the debug info that says "this
variable is the `this` pointer" other than the name/type of a variable
and the type of the function.
Depends on
* https://github.com/llvm/llvm-project/pull/148877
* https://github.com/llvm/llvm-project/pull/155483
* https://github.com/llvm/llvm-project/pull/155485
* https://github.com/llvm/llvm-project/pull/154137
* https://github.com/llvm/llvm-project/pull/154142
This patch is an implementation of [this
discussion](https://discourse.llvm.org/t/rfc-lldb-handling-abi-tagged-constructors-destructors-in-expression-evaluator/82816/7)
about handling ABI-tagged structors during expression evaluation.
**Motivation**
LLDB encodes the mangled name of a `DW_TAG_subprogram` into `AsmLabel`s
on function and method Clang AST nodes. This means that when calls to
these functions get lowered into IR (when running JITted expressions),
the address resolver can locate the appropriate symbol by mangled name
(and it is guaranteed to find the symbol because we got the mangled name
from debug-info, instead of letting Clang mangle it based on AST
structure). However, we don't do this for
`CXXConstructorDecl`s/`CXXDestructorDecl`s because these structor
declarations in DWARF don't have a linkage name. This is because there
can be multiple variants of a structor, each with a distinct mangling in
the Itanium ABI. Each structor variant has its own definition
`DW_TAG_subprogram`. So LLDB doesn't know which mangled name to put into
the `AsmLabel`.
Currently this means using ABI-tagged structors in LLDB expressions
won't work (see [this
RFC](https://discourse.llvm.org/t/rfc-lldb-handling-abi-tagged-constructors-destructors-in-expression-evaluator/82816)
for concrete examples).
**Proposed Solution**
The `FunctionCallLabel` encoding that we put into `AsmLabel`s already
supports stuffing more info about a DIE into it. So this patch extends
the `FunctionCallLabel` to contain an optional discriminator (a sequence
of bytes) which the `SymbolFileDWARF` plugin interprets as the
constructor/destructor variant of that DIE. So when searching for the
definition DIE, LLDB will include the structor variant in its heuristic
for determining a match.
There's a few subtleties here:
1. At the point at which LLDB first constructs the label, it has no way
of knowing (just by looking at the debug-info declaration), which
structor variant the expression evaluator is supposed to call. That's
something that gets decided when compiling the expression. So we let the
Clang mangler inject the correct structor variant into the `AsmLabel`
during JITing. I adjusted the `AsmLabelAttr` mangling for this in
https://github.com/llvm/llvm-project/pull/155485. An option would've
been to create a new Clang attribute which behaved like an `AsmLabel`
but with these special semantics for LLDB. My main concern there is that
we'd have to adjust all the `AsmLabelAttr` checks around Clang to also
now account for this new attribute.
2. The compiler is free to omit the `C1` variant of a constructor if the
`C2` variant is sufficient. In that case it may alias `C1` to `C2`,
leaving us with only the `C2` `DW_TAG_subprogram` in the object file.
Linux is one of the platforms where this occurs. For those cases I added
a heuristic in `SymbolFileDWARF` where we pick `C2` if we asked for `C1`
but it doesn't exist. This may not always be correct (e.g., if the
compiler decided to drop `C1` for other reasons).
3. In https://github.com/llvm/llvm-project/pull/154142 Clang will emit
`C4`/`D4` variants of ctors/dtors on declarations. When resolving the
`FunctionCallLabel` we will now substitute the actual variant that Clang
told us we need to call into the mangled name. We do this using LLDB's
`ManglingSubstitutor`. That way we find the definition DIE exactly the
same way we do for regular function calls.
4. In cases where declarations and definitions live in separate modules,
the DIE ID encoded in the function call label may not be enough to find
the definition DIE in the encoded module ID. For those cases we fall
back to how LLDB used to work: look up in all images of the target. To
make sure we don't use the unified mangled name for the fallback lookup,
we change the lookup name to whatever mangled name the FunctionCallLabel
resolved to.
rdar://104968288
To find global variables, `SymbolFileNativePDB` used to search the
globals stream for the name passed to `FindGlobalVariables`. However,
the symbols in the globals stream contain the fully qualified name and
`FindGlobalVariables` only gets the basename. The approach here is
similar to the one for types and functions.
As we already search the globals stream for functions, we can cache the
basenames for global variables there as well.
This makes the `expressions.test` from the DIA PDB plugin pass with the
native one (#114906).
## Summary
A new `totalDwoErrorCount` counter is available in statistics when
calling `statistics dump` to track the number of DWO errors.
Additionally, this PR refactors the DWO file statistics by consolidating
the existing functionality for counting loaded and total DWO files
together with the number of DWO errors into a single function that
returns a new DWOStats struct.
1. A new struct, `DWOStats` is created to hold the number of loaded DWO
files, the total number of DWO files and the number of DWO errors.
2. Replaced the previous `GetDwoFileCounts` function for loaded and
total DWO file counts with a single `GetDwoStats()` function returning
the struct `DWOStats`. An override is implemented for `SymbolFileDWARF`
that computes the new DWO error count alongside existing counts in one
pass. If the status of a DWO CU is `Fail`, which means there is error
happened during the loading process, we increment the DWO error counter.
_Note: The newly created function `GetDwoStats` will only be called when
we try to get statistics. Other codepaths will not be affected._
3. In Statistics, we sum up the total number of DWO file loading errors.
This is done by getting `DWOStats` for each symbol file and adding up
the results for each module, then adding to the total count among all
modules.
4. In Statistics, we also updated call sites to use the new combined
function and struct for loaded and total DWO file counts. As it is
possible for one module to have several symbol files, the DWO file
counts in a module's stats are updated to be calculated by adding up the
counts from all symbol files.
## Expected Behavior
- When binaries are compiled with split-dwarf and separate DWO files,
`totalDwoLoadErrorCount` would be the number of dwo files with error
occurs during the loading process, 0 if no error occurs during a loading
process.
- When not using split-dwarf, we expect `totalDwoLoadErrorCount` to be 0
since there no DWO file loading errors would be caused.
- `totalLoadedDwoFileCount` and `totalDwoFileCount` should be correctly
calculated after refactoring and updating.
## Testing
### Manual Testing
We created some files to simulate the possible DWO errors manually and
observed the results generated by statistics dump.
For example, if we delete one of the DWO files generated after
compiling, we would get:
```
(lldb) statistics dump
{
...
"totalDwoLoadErrorCount": 1,
...
}
```
We also checked the time cost of `statistics dump` w/o the modification
to make sure no significant time cost increase imported.
### Unit test
Added two unit tests that build with new "dwo_error_foo.cpp" and
"dwo_error_main.cpp" files. For tests with flags -gsplit-dwarf, this
generates 2 DWO files.
In one of the tests, we delete both DWO files and check the result to
see if it reflects the number of DWO files with errors correctly. In
another test we update one of the files but loading the outdated .dwo
file of it, expecting it increments the error count by 1.
To run the test:
```
$ bin/lldb-dotest -p TestStats.py ~/local/llvm-project/lldb/test/API/commands/statistics/basic/ -G "dwo"
----------------------------------------------------------------------
Ran 27 tests in 2.680s
OK (skipped=21)
$ bin/lldb-dotest -p TestStats.py ~/local/llvm-project/lldb/test/API/commands/statistics/basic/
----------------------------------------------------------------------
Ran 27 tests in 370.131s
OK (skipped=3)
```
This upstreams https://github.com/swiftlang/llvm-project/pull/10313.
If we detect a situation where a forward declaration is C++ and the
definition DIE is Objective-C, then just don't try to complete the type
(it would crash otherwise). In the long term we might want to add
support for completing such types.
We've seen real world crashes when debugging WebKit and wxWidgets
because of this. Both projects forward declare ObjC++ decls in the way
shown in the test.
rdar://145959981
https://github.com/llvm/llvm-project/pull/153160 created those function
maps and uses default sort comparator which is not deterministic when
there are multiple entries with same name because llvm::sort is unstable
sort.
This fixes it by comparing the id value when tie happens and sort
`m_type_base_names` deterministically as well.
This reintroduces `Type.h`, having earlier been renamed to `TypeBase.h`,
as a redirection to `TypeBase.h`, and redirects most users to include
the former instead.
This is a preparatory patch for being able to provide inline definitions
for `Type` methods which would otherwise cause a circular dependency
with `Decl{,CXX}.h`.
Doing these operations into their own NFC patch helps the git rename
detection logic work, preserving the history.
This patch makes clang just a little slower to build (~0.17%), just
because it makes more code indirectly include `DeclCXX.h`.
This is a preparatory patch, to be able to provide inline definitions
for `Type` functions which depend on `Decl{,CXX}.h`. As the latter also
depends on `Type.h`, this would not be possible without some
reorganizing.
Splitting this rename into its own patch allows git to track this as a
rename, and preserve all git history, and not force any code
reformatting.
A later NFC patch will reintroduce `Type.h` as redirection to
`TypeBase.h`, rewriting most places back to directly including `Type.h`
instead of `TypeBase.h`, leaving only a handful of places where this is
necessary.
Then yet a later patch will exploit this by making more stuff inline.
I'm trying to remove the redirection in SmallSet.h:
template <typename PointeeType, unsigned N>
class SmallSet<PointeeType*, N> : public SmallPtrSet<PointeeType*, N>
{};
to make it clear that we are using SmallPtrSet. There are only
handful places that rely on this redirection.
This patch replaces SmallSet to SmallPtrSet where the element type is
a pointer.
This patch replaces SmallSet<T *, N> with SmallPtrSet<T *, N>. Note
that SmallSet.h "redirects" SmallSet to SmallPtrSet for pointer
element types:
template <typename PointeeType, unsigned N>
class SmallSet<PointeeType*, N> : public SmallPtrSet<PointeeType*, N>
{};
We only have 10 instances that rely on this "redirection". Since the
redirection doesn't improve readability, this patch replaces SmallSet
with SmallPtrSet for pointer element types.
I'm planning to remove the redirection eventually.
This patch fixes:
lldb/source/Plugins/SymbolFile/NativePDB/SymbolFileNativePDB.cpp:647:3:
error: 'llvm::Expected' may not intend to support class template
argument deduction [-Werror,-Wctad-maybe-unsupported]
lldb/source/Plugins/SymbolFile/NativePDB/SymbolFileNativePDB.cpp:677:3:
error: 'llvm::Expected' may not intend to support class template
argument deduction [-Werror,-Wctad-maybe-unsupported]
Tag types like stucts or enums didn't have a declaration attached to
them. The source locations are present in the IPI stream in
`LF_UDT_MOD_SRC_LINE` records:
```
0x101F | LF_UDT_MOD_SRC_LINE [size = 18, hash = 0x1C63]
udt = 0x1058, mod = 3, file = 1, line = 0
0x2789 | LF_UDT_MOD_SRC_LINE [size = 18, hash = 0x1E5A]
udt = 0x1253, mod = 35, file = 93, line = 17069
```
The file is an ID in the string table `/names`:
```
ID | String
1 | '\<unknown>'
12 | 'D:\a\_work\1\s\src\ExternalAPIs\WindowsSDKInc\c\Include\10.0.22621.0\um\wingdi.h'
93 | 'D:\a\_work\1\s\src\ExternalAPIs\WindowsSDKInc\c\Include\10.0.22621.0\um\winnt.h'
```
Here, we're not interested in `mod`. This would indicate which module
contributed the UDT.
I was looking at Rustc's PDB and found that it uses `<unknown>` for some
types, so I added a check for that.
This makes two DIA PDB shell tests to work with the native PDB plugin.
---------
Co-authored-by: Michael Buch <michaelbuch12@gmail.com>
Relands #152295.
Checking for the overloads did not account for them being out of order.
For example, [the failed
output](https://github.com/llvm/llvm-project/pull/152295#issuecomment-3177563247)
contained the overloads, but out of order. The last commit here fixes
that by using `-DAG`.
---------
Co-authored-by: Jonas Devlieghere <jonas@devlieghere.com>
This adds the ability for functions to be matched by their basename.
Before, the globals were searched for the name. This works if the full
name is available but fails for basenames.
PDB only includes the full names of functions, so we need to cache all
basenames. This is (again) very similar to
[SymbolFilePDB](b242150b07/lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.cpp (L1291-L1383)).
There are two main differences:
- We can't just access the parent of a function to determine that it's a
member function - we need to check the type of the function, and its
"this type".
- SymbolFilePDB saved the full method name in the map. However, when
searching for methods, only the basename is passed, so the function
never found any methods.
Fixes#51933.
---------
Co-authored-by: Jonas Devlieghere <jonas@devlieghere.com>
This is a major change on how we represent nested name qualifications in
the AST.
* The nested name specifier itself and how it's stored is changed. The
prefixes for types are handled within the type hierarchy, which makes
canonicalization for them super cheap, no memory allocation required.
Also translating a type into nested name specifier form becomes a no-op.
An identifier is stored as a DependentNameType. The nested name
specifier gains a lightweight handle class, to be used instead of
passing around pointers, which is similar to what is implemented for
TemplateName. There is still one free bit available, and this handle can
be used within a PointerUnion and PointerIntPair, which should keep
bit-packing aficionados happy.
* The ElaboratedType node is removed, all type nodes in which it could
previously apply to can now store the elaborated keyword and name
qualifier, tail allocating when present.
* TagTypes can now point to the exact declaration found when producing
these, as opposed to the previous situation of there only existing one
TagType per entity. This increases the amount of type sugar retained,
and can have several applications, for example in tracking module
ownership, and other tools which care about source file origins, such as
IWYU. These TagTypes are lazily allocated, in order to limit the
increase in AST size.
This patch offers a great performance benefit.
It greatly improves compilation time for
[stdexec](https://github.com/NVIDIA/stdexec). For one datapoint, for
`test_on2.cpp` in that project, which is the slowest compiling test,
this patch improves `-c` compilation time by about 7.2%, with the
`-fsyntax-only` improvement being at ~12%.
This has great results on compile-time-tracker as well:
This patch also further enables other optimziations in the future, and
will reduce the performance impact of template specialization resugaring
when that lands.
It has some other miscelaneous drive-by fixes.
About the review: Yes the patch is huge, sorry about that. Part of the
reason is that I started by the nested name specifier part, before the
ElaboratedType part, but that had a huge performance downside, as
ElaboratedType is a big performance hog. I didn't have the steam to go
back and change the patch after the fact.
There is also a lot of internal API changes, and it made sense to remove
ElaboratedType in one go, versus removing it from one type at a time, as
that would present much more churn to the users. Also, the nested name
specifier having a different API avoids missing changes related to how
prefixes work now, which could make existing code compile but not work.
How to review: The important changes are all in
`clang/include/clang/AST` and `clang/lib/AST`, with also important
changes in `clang/lib/Sema/TreeTransform.h`.
The rest and bulk of the changes are mostly consequences of the changes
in API.
PS: TagType::getDecl is renamed to `getOriginalDecl` in this patch, just
for easier to rebasing. I plan to rename it back after this lands.
Fixes#136624
Fixes https://github.com/llvm/llvm-project/issues/43179
Fixes https://github.com/llvm/llvm-project/issues/68670
Fixes https://github.com/llvm/llvm-project/issues/92757
Factors out code to locate a definition DIE from a `FunctionCallLabel`
into a helper. This will be useful for an upcoming refactor that extends
`FindFunctionDefinition`.
Drive-by:
* adjusts some error messages in the `FunctionCallLabel` support code.
Fixes a bug that surfaces in frame recognizers.
Details about the bug:
A new frame recognizer is configured to match a specific symbol
(`swift_willThrow`). This is an `extern "C"` symbol defined in a C++
source file. When Swift is built with debug info, the function
`ParseFunctionFromDWARF` will use the debug info to construct a function
name that looks like a C++ declaration (`::swift_willThrow(void *,
SwiftError**)`). The `Mangled` instance will have this string as its
`m_demangled` field, and have _no_ string for its `m_mangled` field.
The result is the frame recognizer would not match the symbol to the
name (`swift_willThrow` != `::swift_willThrow(void *, SwiftError**)`.
By changing `ParseFunctionFromDWARF` to assign both a demangled name and
a mangled, frame recognizers can successfully match symbols in this
configuration.
Languages other than C/C++ don't necessarily emit mangled names in the
`UniqueName` field of type records. Rust specifically emits a unique ID
that doesn't contain the name.
For example, `(i32, i32)` is emitted as
```llvm
!266 = !DICompositeType(
tag: DW_TAG_structure_type, name: "tuple$<i32,i32>", file: !9, size: 64, align: 32,
elements: !267, templateParams: !17, identifier: "19122721b0632fe96c0dd37477674472"
)
```
which results in
```
0x1091 | LF_STRUCTURE [size = 72, hash = 0x1AC67] `tuple$<i32,i32>`
unique name: `19122721b0632fe96c0dd37477674472`
vtable: <no type>, base list: <no type>, field list: 0x1090
options: has unique name, sizeof 8
```
In C++ with Clang and MSVC, a structure similar to this would result in
```
0x136F | LF_STRUCTURE [size = 44, hash = 0x30BE2] `MyTuple`
unique name: `.?AUMyTuple@@`
vtable: <no type>, base list: <no type>, field list: 0x136E
options: has unique name, sizeof 8
```
With this PR, if a `UniqueName` is encountered that couldn't be parsed,
it will fall back to using the undecorated (→ do the same as if the
unique name is empty/unavailable).
I'm not sure how to test this. Maybe compiling the LLVM IR that rustc
emits?
Fixes#152051.
