Before:
```
(lldb) expression some_template_func<int, long>(5)
˄
╰─ error: 'some_template_func' does not name a template but is followed by template arguments
note: Ran expression as 'C++14'.
note: note: non-template declaration found by name lookup
```
After:
```
(lldb) expression some_template_func<int, long>(5)
˄
╰─ error: 'some_template_func' does not name a template but is followed by template arguments
note: Ran expression as 'C++14'.
note: note: non-template declaration found by name lookup
note: Naming template instantiation not yet supported. Template functions can be invoked via their mangled name. E.g., expression _Z3fooIiEvi(5)
```
There isn't a great way to get to the actual function being named (and
its mangled name) since we're just dealing with raw text. So I just
print an example mangled name.
This doesn't work for all template instantiations. E.g.,:
```
(lldb) p f.method<long>(10)
˄ ˄
│ ╰─ error: expected '(' for function-style cast or type construction
╰─ error: no member named 'method' in 'Foo<int>'
note: Ran expression as 'C++14'.
```
This is a consequence of how we construct the AST for template methods.
Once we fix that, this hint will get emitted there too.
Note this will also trigger in cases where no function is being called
(hence I used the defensive phrase "Template functions can be invoked").
rdar://135725807
Depends on:
* https://github.com/llvm/llvm-project/pull/177921
* https://github.com/llvm/llvm-project/pull/177926
(only last commit is relevant for this review)
This patch emits a workaround suggestion (in the form of a `note:`
diagnostic) when an expression fails due to trying to mutate state/call
functions with CV-qualifiers that are disallowed by C++ language rules
based on the context the expression is evaluated in. The note looks as
follows:
```
(lldb) expr next.method()
˄
╰─ error: 'this' argument to member function 'method' has type 'const Bar', but function is not marked const
note: Ran expression as 'C++14'.
note: note: 'method' declared here
note: Possibly trying to mutate object in a const context. Try running the expression with: expression --c++-ignore-context-qualifiers -- <your expression>
```
Depends on:
* https://github.com/llvm/llvm-project/pull/166917
* https://github.com/llvm/llvm-project/pull/166940
While these errors can contribute to an expression failing, they are
never *the* reason the expression failed. I.e., they are always just
'note:' diagnostics that we hand-emit. Because they are quite noisy (and
we potentially have many of them if we auto-load all modules in a CU),
this patch logs the errors to the `expr` log, instead of the console.
Previously these errors would only get omitted when the expression
itself failed. Meaning if the expression failed, we'd dump these 'note'
module load errors in next to the actual expression error, obscuring the
output. Moreover, if the expression succeeded, any module load errors
would be dropped. Now we always log all module loading errors to the
expression log, regardless of whether the expression fails or not.
Depends on:
* https://github.com/llvm/llvm-project/pull/166917
When loading all Clang modules for a CU, we stop on first error. This
means benign module loading errors may stop us from importing actually
useful modules. There's no good reason to bail on the first one. The
pathological case would be if we try to load a large number of Clang
modules
but all fail to load for the same reason. That could happen, but in
practice I've always seen only a handful of modules failing to load out
of a large number. Particularly system modules are useful and usually
don't fail to load. Whereas project-specific Clang modules are more
likely to fail because the build system moves the modulemap/sources
around.
This patch accumulates all module loading errors and doesn't stop when
an error is encountered.
Instead of propagating the errors as a `bool`+`Stream` we change the
`ClangModulesDeclVendor` module loading APIs to use `llvm::Error`. We
also reword some of the diagnostics (notably removing the hardcoded
`error:` prefix). A follow-up patch will further make the module loading
errors less noisy.
See the new tests for what the errors look like.
rdar://164002569
Depends on:
* https://github.com/llvm/llvm-project/pull/162050
Since it's a 'Note' diagnostic it would only show up when expression
evaluation actually failed. This helps with expression evaluation
failure reports in mixed language environments where it's not quite
clear what language the expression ran as. It may also reduce confusion
around why the expression evaluator ran an expression in a language it
wasn't asked to run (a softer alternative to what I attempted in
https://github.com/llvm/llvm-project/pull/156648).
Here are some example outputs:
```
# Without target
(lldb) expr blah
note: Falling back to default language. Ran expression as 'Objective C++'.
# Stopped in target
(lldb) expr blah
note: Ran expression as 'C++14'.
(lldb) expr -l objc -- blah
note: Expression evaluation in pure Objective-C not supported. Ran expression as 'Objective C++'.
(lldb) expr -l c -- blah
note: Expression evaluation in pure C not supported. Ran expression as 'ISO C++'.
(lldb) expr -l c++14 -- blah
note: Ran expression as 'C++14'
(lldb) expr -l c++20 -- blah
note: Ran expression as 'C++20'
(lldb) expr -l objective-c++ -- blah
note: Ran expression as 'Objective C++'
(lldb) expr -l D -- blah
note: Expression evaluation in D not supported. Falling back to default language. Ran expression as 'Objective C++'.
```
I didn't put the diagnostic on the same line as the inline diagnostic
for now because of implementation convenience, but if reviewers deem
that a blocker I can take a stab at that again.
Also, other language plugins (namely Swift), won't immediately benefit
from this and will have to emit their own diagnistc. I played around
with having a virtual API on `UserExpression` or `ExpressionParser` that
will be called consistently, but by the time we're about to parse the
expression we are already several frames deep into the plugin. Before
(and at the beginning of) the generic `UserExpression::Parse` call we
don't have enough information to notify which language we're going to
parse in (at least for the C++ plugin).
rdar://160297649
rdar://159669244
The problem was in calling GetLoadAddress on a value in the error state,
where `ValueObject::GetLoadAddress` could end up accessing the
uninitialized "address type" by-ref return value from `GetAddressOf`.
This probably happened because each function expected the other to
initialize it.
We can guarantee initialization by turning this into a proper return
value.
I've added a test, but it only (reliably) crashes if lldb is built with
ubsan.
ValueObject is part of lldbCore for historical reasons, but conceptually
it deserves to be its own library. This does introduce a (link-time) circular
dependency between lldbCore and lldbValueObject, which is unfortunate
but probably unavoidable because so many things in LLDB rely on
ValueObject. We already have cycles and these libraries are never built
as dylibs so while this doesn't improve the situation, it also doesn't
make things worse.
The header includes were updated with the following command:
```
find . -type f -exec sed -i.bak "s%include \"lldb/Core/ValueObject%include \"lldb/ValueObject/ValueObject%" '{}' \;
```
This patch removes all of the Set.* methods from Status.
This cleanup is part of a series of patches that make it harder use the
anti-pattern of keeping a long-lives Status object around and updating
it while dropping any errors it contains on the floor.
This patch is largely NFC, the more interesting next steps this enables
is to:
1. remove Status.Clear()
2. assert that Status::operator=() never overwrites an error
3. remove Status::operator=()
Note that step (2) will bring 90% of the benefits for users, and step
(3) will dramatically clean up the error handling code in various
places. In the end my goal is to convert all APIs that are of the form
` ResultTy DoFoo(Status& error)
`
to
` llvm::Expected<ResultTy> DoFoo()
`
How to read this patch?
The interesting changes are in Status.h and Status.cpp, all other
changes are mostly
` perl -pi -e 's/\.SetErrorString/ = Status::FromErrorString/g' $(git
grep -l SetErrorString lldb/source)
`
plus the occasional manual cleanup.
This patch changes the return type of `GetMetadata` from a
`ClangASTMetadata*` to a `std::optional<ClangASTMetadata>`. Except for
one call-site (`SetDeclIsForcefullyCompleted`), we never actually make
use of the mutability of the returned metadata. And we never make use of
the pointer-identity. By passing `ClangASTMetadata` by-value (the type
is fairly small, size of 2 64-bit pointers) we'll avoid some questions
surrounding the lifetimes/ownership/mutability of this metadata.
For consistency, we also change the parameter to `SetMetadata` from
`ClangASTMetadata&` to `ClangASTMetadata` (which is an NFC since we copy
the data anyway).
This came up during some changes we plan to make where we [create
redeclaration chains for decls in the LLDB
AST](https://github.com/llvm/llvm-project/pull/95100). We want to avoid
having to dig out the canonical decl of the declaration chain for
retrieving/setting the metadata. It should just be copied across all
decls in the chain. This is easier to guarantee when everything is done
by-value.
This patch adds a new `DoPrepareForExecution` API, which can be
implemented by the Clang and Swift language plugins. This also moves
`RunStaticInitializers` into `ExpressionParser::PrepareForExecution`, so
we call it consistently between language plugins.
This *should* be mostly NFC (the static initializers will still only run
after we finished parsing). We've been living on this patch downstream
for sometime now.
rdar://130267058
that separates out language and version. To avoid reinventing the wheel
and introducing subtle incompatibilities, this API uses the table of
languages and versiond defined by the upcoming DWARF 6 standard
(https://dwarfstd.org/languages-v6.html). While the DWARF 6 spec is not
finialized, the list of languages is broadly considered stable.
The primary motivation for this is to allow the Swift language plugin to
switch between language dialects between, e.g., Swift 5.9 and 6.0 with
out introducing a ton of new language codes. On the main branch this
change is considered NFC.
Depends on https://github.com/llvm/llvm-project/pull/89980
The `ClangExpressionParser` takes an `ExecutionContextScope` which it
uses to query the `Process`/`Target`/`StackFrame` to set various
compiler options in preparation for parsing an expression.
However, `TryParse` constructs the parser with a `Process` or `Target`,
never a `StackFrame`. So when the parser tries to retrieve the current
`StackFrame` from the `exe_scope`, it doesn't succeed. In future patches
we want to query the `StackFrame` from within the
`ClangExpressionParser` constructor.
This patch simplifies `TryParse`, by removing the redundant `exe_scope`
parameter, and instead uses the `exe_ctx` to derive the most fitting
`exe_scope` to pass into `ClangExpressionParser`.
Not entirely sure how to test this. This patch is a prerequisite to get
subsequent patches that set `LangOpts` based on the current `StackFrame`
to work.
LLVM supports DWARF 5 linetable extension to store source files inline
in DWARF. This is particularly useful for compiler-generated source
code. This implementation tries to materialize them as temporary files
lazily, so SBAPI clients don't need to be aware of them.
rdar://110926168
GetObjectPointer (and other related methods) do not need `ConstString`
parameters. The string parameter in these methods boil down to getting a
StringRef and calling `StackFrame::GetValueForVariableExpressionPath`
which takes a `StringRef` parameter. All the users of `GetObjectPointer`
(and related methods) end up creating ConstString objects to pass to
these methods, but they could just as easily be StringRefs (potentially
saving us some allocations in the StringPool).
StreamFile subclasses Stream (from lldbUtility) and is backed by a File
(from lldbHost). It does not depend on anything from lldbCore or any of its
sibling libraries, so I think it makes sense for this to live in
lldbHost instead.
Differential Revision: https://reviews.llvm.org/D157460
It turns out all existing callers of `GetChildMemberWithName` pass true for `can_create`.
This change makes `true` the default value, callers don't have to pass an opaque true.
Differential Revision: https://reviews.llvm.org/D151966
`GetChildMemberWithName` does not need a `ConstString`. This change makes the function
take a `StringRef` instead, which alleviates the need for callers to construct a
`ConstString`. I don't expect this change to improve performance, only ergonomics.
This is in support of Alex's effort to replace `ConstString` where appropriate.
There are related `ValueObject` functions that can also be changed, if this is accepted.
Differential Revision: https://reviews.llvm.org/D151615
Resubmission of https://reviews.llvm.org/D130309 with the 2 patches that fixed the linux buildbot, and new windows fixes.
The FileSpec APIs allow users to modify instance variables directly by getting a non const reference to the directory and filename instance variables. This makes it impossible to control all of the times the FileSpec object is modified so we can clear cached member variables like m_resolved and with an upcoming patch caching if the file is relative or absolute. This patch modifies the APIs of FileSpec so no one can modify the directory or filename instance variables directly by adding set accessors and by removing the get accessors that are non const.
Many clients were using FileSpec::GetCString(...) which returned a unique C string from a ConstString'ified version of the result of GetPath() which returned a std::string. This caused many locations to use this convenient function incorrectly and could cause many strings to be added to the constant string pool that didn't need to. Most clients were converted to using FileSpec::GetPath().c_str() when possible. Other clients were modified to use the newly renamed version of this function which returns an actualy ConstString:
ConstString FileSpec::GetPathAsConstString(bool denormalize = true) const;
This avoids the issue where people were getting an already uniqued "const char *" that came from a ConstString only to put the "const char *" back into a "ConstString" object. By returning the ConstString instead of a "const char *" clients can be more efficient with the result.
The patch:
- Removes the non const GetDirectory() and GetFilename() get accessors
- Adds set accessors to replace the above functions: SetDirectory() and SetFilename().
- Adds ClearDirectory() and ClearFilename() to replace usage of the FileSpec::GetDirectory().Clear()/FileSpec::GetFilename().Clear() call sites
- Fixed all incorrect usage of FileSpec::GetCString() to use FileSpec::GetPath().c_str() where appropriate, and updated other call sites that wanted a ConstString to use the newly returned ConstString appropriately and efficiently.
Differential Revision: https://reviews.llvm.org/D130549
This reverts commit 9429b67b8e300e638d7828bbcb95585f85c4df4d.
It broke the build on Windows, see comments on https://reviews.llvm.org/D130309
It also reverts these follow-ups:
Revert "Fix buildbot breakage after https://reviews.llvm.org/D130309."
This reverts commit f959d815f4637890ebbacca379f1c38ab47e4e14.
Revert "Fix buildbot breakage after https://reviews.llvm.org/D130309."
This reverts commit 0bbce7a4c2d2bff622bdadd4323f93f5d90e6d24.
Revert "Cache the value for absolute path in FileSpec."
This reverts commit dabe877248b85b34878e75d5510339325ee087d0.
The FileSpect APIs allow users to modify instance variables directly by getting a non const reference to the directory and filename instance variables. This makes it impossibly to control all of the times the FileSpec object is modified so we can clear the cache. This patch modifies the APIs of FileSpec so no one can modify the directory or filename directly by adding set accessors and by removing the get accessors that are non const.
Many clients were using FileSpec::GetCString(...) which returned a unique C string from a ConstString'ified version of the result of GetPath() which returned a std::string. This caused many locations to use this convenient function incorrectly and could cause many strings to be added to the constant string pool that didn't need to. Most clients were converted to using FileSpec::GetPath().c_str() when possible. Other clients were modified to use the newly renamed version of this function which returns an actualy ConstString:
ConstString FileSpec::GetPathAsConstString(bool denormalize = true) const;
This avoids the issue where people were getting an already uniqued "const char *" that came from a ConstString only to put the "const char *" back into a "ConstString" object. By returning the ConstString instead of a "const char *" clients can be more efficient with the result.
The patch:
- Removes the non const GetDirectory() and GetFilename() get accessors
- Adds set accessors to replace the above functions: SetDirectory() and SetFilename().
- Adds ClearDirectory() and ClearFilename() to replace usage of the FileSpec::GetDirectory().Clear()/FileSpec::GetFilename().Clear() call sites
- Fixed all incorrect usage of FileSpec::GetCString() to use FileSpec::GetPath().c_str() where appropriate, and updated other call sites that wanted a ConstString to use the newly returned ConstString appropriately and efficiently.
Differential Revision: https://reviews.llvm.org/D130309
This patch adds support for evaluating expressions which reference
a captured `this` from within the context of a C++ lambda expression.
Currently LLDB doesn't provide Clang with enough information to
determine that we're inside a lambda expression and are allowed to
access variables on a captured `this`; instead Clang simply fails
to parse the expression.
There are two problems to solve here:
1. Make sure `clang::Sema` doesn't reject the expression due to an
illegal member access.
2. Materialize all the captured variables/member variables required
to evaluate the expression.
To address (1), we currently import the outer structure's AST context
onto `$__lldb_class`, making the `contextClass` and the `NamingClass`
match, a requirement by `clang::Sema::BuildPossibleImplicitMemberExpr`.
To address (2), we inject all captured variables as locals into the
expression source code.
**Testing**
* Added API test
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.
On Linux some C++ and C include files reside in target specific directories, like /usr/include/x86_64-linux-gnu.
Patch adds them to libclang, so LLDB jitter has more chances to compile expression.
OS Laboratory. Huawei Russian Research Institute. Saint-Petersburg
Reviewed By: teemperor
Differential Revision: https://reviews.llvm.org/D110827
The `fallback` setting for import-std-module is supposed to allow running
expression that require an imported C++ module without causing any regressions
for users (neither in terms of functionality nor performance). This is done by
first trying to normally parse/evaluate an expression and when an error occurred
during this first attempt, we retry with the loaded 'std' module.
When we run into a system with a 'std' module that for some reason doesn't build
or otherwise causes parse errors, then this currently means that the second
parse attempt will overwrite the error diagnostics of the first parse attempt.
Given that the module build errors are outside of the scope of what the user can
influence, it makes more sense to show the errors from the first parse attempt
that are only concerned with the actual user input.
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D110696
LLVM includes this header unconditionally on all platforms
(including Windows), so this define should no longer be necessary.
No behavior change.
Differential Revision: https://reviews.llvm.org/D107338
This reverts commit 00764c36edf88ae9806e8d57a6addb782e6ceae8 and the
follow up d2223c7a49973a61cc2de62992662afa8d19065a.
The original patch broke that one could use static member variables while
inside a static member functions without having a running target. It seems that
LLDB currently requires that static variables are only found via the global
variable lookup so that they can get materialized and mapped to the argument
struct of the expression.
After 00764c36edf88ae9806e8d57a6addb782e6ceae8 static variables of the current
class could be found via Clang's lookup which LLDB isn't observing. This
resulting in expressions actually containing these variables as normal
globals that can't be rewritten to a member of the argument struct.
More specifically, in the test TestCPPThis, the expression
`expr --j false -- s_a` is now only passing if we have a runnable target.
I'll revert the patch as the possible fixes aren't trivial and it degrades
the debugging experience more than the issue that the revert patch addressed.
The underlying bug can be reproduced before/after this patch by stopping
in `TestCPPThis` main function and running: `e -j false -- my_a; A<int>::s_a`.
The `my_a` will pull in the `A<int>` class and the second expression will
be resolved by Clang on its own (which causes LLDB to not materialize the
static variable).
Note: A workaround is to just do `::s_a` which will force LLDB to take the global
variable lookup.
The C headers are deprecated so as requested in D102845, this is replacing them
all with their (not deprecated) C++ equivalent.
Reviewed By: shafik
Differential Revision: https://reviews.llvm.org/D103084
More decoupling of plugins and non-plugins. Target doesn't need to
manage ClangModulesDeclVendor and ClangPersistentVariables is always available
in situations where you need ClangModulesDeclVendor.
Differential Revision: https://reviews.llvm.org/D102811
At the moment the expression parser doesn't support evaluating expressions in
static member functions and just pretends the expression is evaluated within a
non-member function. This causes that all static members are inaccessible when
doing unqualified name lookup.
This patch adds support for evaluating in static member functions. It
essentially just does the same setup as what LLDB is already doing for
non-static member functions (i.e., wrapping the expression in a fake member
function) with the difference that we now mark the wrapping function as static
(to prevent access to non-static members).
Reviewed By: shafik, jarin
Differential Revision: https://reviews.llvm.org/D81550
By now LLDB can import the 'std' C++ module to improve expression evaluation,
but there are still a few problems to solve before we can do this by default.
One is that importing the C++ module is slightly slower than normal expression
evaluation (mostly because the disk access and loading the initial lookup data
is quite slow in comparison to the barebone Clang setup the rest of the LLDB
expression evaluator is usually doing). Another problem is that some complicated
types in the standard library aren't fully supported yet by the ASTImporter, so
we end up types that fail to import (which usually appears to the user as if the
type is empty or there is just no result variable).
To still allow people to adopt this mode in their daily debugging, this patch
adds a setting that allows LLDB to automatically retry failed expression with a
loaded C++ module. All success expressions will behave exactly as they would do
before this patch. Failed expressions get a another parse attempt if we find a
usable C++ module in the current execution context. This way we shouldn't have
any performance/parsing regressions in normal debugging workflows, while the
debugging workflows involving STL containers benefit from the C++ module type
info.
This setting is off by default for now with the intention to enable it by
default on macOS soon-ish.
The implementation is mostly just extracting the existing parse logic into its
own function and then calling the parse function again if the first evaluation
failed and we have a C++ module to retry the parsing with.
Reviewed By: shafik, JDevlieghere, aprantl
Differential Revision: https://reviews.llvm.org/D92784
Summary:
ClangExpressionSourceCode has different ways to wrap the user expression based on
which context the expression is executed in. For example, if we're in a C++ member
function we put the expression inside a fake member function of a fake class to make the
evaluation possible. Similar things are done for Objective-C instance/static methods.
There is also a default wrapping where we put the expression in a normal function
just to make it possible to execute it.
The way we currently define which kind of wrapping the expression needs is based on
the `wrapping_language` we keep passing to the ClangExpressionSourceCode
instance. We repurposed the language type enum for that variable to distinguish the
cases above with the following mapping:
* language = C_plus_plus -> member function wrapping
* language = ObjC -> instance/static method wrapping (`is_static` distinguished between those two).
* language = C -> normal function wrapping
* all other cases like C_plus_plus11, Haskell etc. make our class a no-op that does mostly nothing.
That mapping is currently not documented and just confusing as the `language`
is unrelated to the expression language (and in the ClangUserExpression we even pretend
that it *is* the actual language, but luckily never used it for anything). Some of the code
in ClangExpressionSourceCode is also obviously thinking that this is the actual language of
the expression as it checks for non-existent cases such as `ObjC_plus_plus` which is
not part of the mapping.
This patch makes a new enum to describe the four cases above (with instance/static Objective-C
methods now being their own case). It also make that enum just a member of
ClangExpressionSourceCode instead of having to pass the same value to the class repeatedly.
This gets also rid of all the switch-case-checks for 'unknown' language such as C_plus_plus11 as this
is no longer necessary.
Reviewers: labath, JDevlieghere
Reviewed By: labath
Subscribers: abidh
Differential Revision: https://reviews.llvm.org/D80793
Summary:
When the ClangModulesDeclVendor currently fails it just prints very basic and often incomplete diagnostics without any source locations:
```
(lldb) p @import Foundation
error: while importing modules:
'foo/bar.h' file not found
could not build module 'Darwin'
[...]
```
or even just
```
(lldb) p @import Foundation
error: while importing modules:
could not build module 'Darwin'
[...]
```
These diagnostics help neither the user nor us with figuring out what is the reason for the failure.
This patch wires up a full TextDiagnosticPrinter in the ClangModulesDeclVendor and makes
sure we always return the error stream to the user when we fail to compile our modules.
Fixes rdar://63216849
Reviewers: aprantl, jdoerfert
Reviewed By: aprantl
Subscribers: JDevlieghere
Differential Revision: https://reviews.llvm.org/D79947
Summary:
Currently top-level expressions won't automatically get Fix-Its applied. The reason
for that is that we only set the `m_fixed_text` member if we have a wrapping
source code (I.e. `m_source_code` is not zero and is wrapping some expressions).
This patch just always sets `m_fixed_text` to get this working.
Reviewers: labath, jingham
Reviewed By: labath
Subscribers: JDevlieghere
Differential Revision: https://reviews.llvm.org/D77042
There an option: EvaluateExpressionOptions::SetResultIsInternal to indicate
whether the result number should be returned to the pool or not. It
got broken when the PersistentExpressionState was refactored.
This fixes the issue and provides a test of the behavior.
Differential Revision: https://reviews.llvm.org/D76532
