Summary:
This commit renames ClangASTContext to TypeSystemClang to better reflect what this class is actually supposed to do
(implement the TypeSystem interface for Clang). It also gets rid of the very confusing situation that we have both a
`clang::ASTContext` and a `ClangASTContext` in clang (which sometimes causes Clang people to think I'm fiddling
with Clang's ASTContext when I'm actually just doing LLDB work).
I also have plans to potentially have multiple clang::ASTContext instances associated with one ClangASTContext so
the ASTContext naming will then become even more confusing to people.
Reviewers: #lldb, aprantl, shafik, clayborg, labath, JDevlieghere, davide, espindola, jdoerfert, xiaobai
Reviewed By: clayborg, labath, xiaobai
Subscribers: wuzish, emaste, nemanjai, mgorny, kbarton, MaskRay, arphaman, jfb, usaxena95, jingham, xiaobai, abidh, JDevlieghere, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D72684
Summary:
I often struggle to understand what exactly LLDB is doing by looking at our expression evaluation logging as our messages look like this:
```
CompleteTagDecl[2] on (ASTContext*)0x7ff31f01d240 Completing (TagDecl*)0x7ff31f01d568 named DeclName1
```
From the log messages it's unclear what this ASTContext is. Is it the scratch context, the expression context, some decl vendor context or a context from a module?
The pointer value isn't helpful for anyone unless I'm in a debugger where I could inspect the memory at the address. But even with a debugger it's not easy to
figure out what this ASTContext is without having deeper understanding about all the different ASTContext instances in LLDB (e.g., valid SourceLocation
from the file system usually means that this is the Objective-C decl vendor, a file name from multiple expressions is probably the scratch context, etc.).
This patch adds a name field to ClangASTContext instances that we can use to store a name which can be used for logging and debugging. With this
our log messages now look like this:
```
CompleteTagDecl[2] on scratch ASTContext. Completing (TagDecl*)0x7ff31f01d568 named Foo
```
We can now also just print a ClangASTContext from the debugger and see a useful name in the `m_display_name` field, e.g.
```
m_display_name = "AST for /Users/user/test/main.o";
```
Reviewers: shafik, labath, JDevlieghere, mib
Reviewed By: shafik
Subscribers: clayborg, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D72391
Summary:
This code is handling debug info paths starting with /proc/self/cwd,
which is one of the mechanisms people use to obtain "relocatable" debug
info (the idea being that one starts the debugger with an appropriate
cwd and things "just work").
Instead of resolving the symlinks inside DWARFUnit, we can do the same
thing more elegantly by hooking into the existing Module path remapping
code. Since llvm::DWARFUnit does not support any similar functionality,
doing things this way is also a step towards unifying llvm and lldb
dwarf parsers.
Reviewers: JDevlieghere, aprantl, clayborg, jdoerfert
Subscribers: lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D71770
Summary:
This change is connected with
https://reviews.llvm.org/D69843
In large codebases, we sometimes see Module::FindFunctions (when called from
ClangExpressionDeclMap::FindExternalVisibleDecls) returning huge amounts of
functions.
In current fix I trying to return only function_fullnames from ManualDWARFIndex::GetFunctions when eFunctionNameTypeFull is passed as argument.
Reviewers: labath, jarin, aprantl
Reviewed By: labath
Subscribers: shafik, clayborg, teemperor, arphaman, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D70846
When trying to interpret an expression with a function call, if the
process hasn't been launched, the expression fails to be interpreted
and the user gets the following error message:
```error: Can't run the expression locally```
This message doesn't explain why the expression failed to be
interpreted, that's why this patch improves the error message that is
displayed when trying to run an expression while no process is running.
rdar://11991708
Differential Revision: https://reviews.llvm.org/D72510
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
Summary:
This is a port of D67803 that was about preventing indirect importing to our scratch context when evaluating expressions.
D67803 already has a pretty long explanation of how this works, but the idea is that instead
of importing declarations indirectly over the expression AST (i.e., Debug info AST -> Expression AST -> scratch AST)
we instead directly import the declaration from the debug info AST to the scratch AST.
The difference from D67803 is that here we have to do this in the ASTImporterDelegate (which is our ASTImporter
subclass we use in LLDB). It has the same information as the ExternalASTMerger in D67803 as it can access the
ClangASTImporter (which also keeps track of where Decls originally came from).
With this patch we can also delete the FieldDecl stealing hack in the ClangASTSource (this was only necessary as the
indirect imports caused the creation of duplicate Record declarations but we needed the fields in the Record decl
we originally found in the scratch ASTContext).
This also fixes the current gmodules failures where we fail to find std::vector fields after an indirect import
over the expression AST (where it seems even our FieldDecl stealing hack can't save us from).
Reviewers: shafik, aprantl
Reviewed By: shafik
Subscribers: JDevlieghere, lldb-commits, mib, labath, friss
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D72507
GetPersistentExpressionStateForLanguage() can return a nullptr if it
cannot construct a typesystem. This patch adds missing nullptr checks
at all uses.
Inspired by rdar://problem/58317195
Differential Revision: https://reviews.llvm.org/D72413
Summary: There are a few places in LLDB where we do a `reinterpret_cast` for conversions that we could also do with `static_cast`. This patch moves all this code to `static_cast`.
Reviewers: shafik, JDevlieghere, labath
Reviewed By: labath
Subscribers: arphaman, usaxena95, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D72161
There is no clang::Action anymore so our forward decl for it and the obsolete pointer in the
ASTStructExtractor can both go (that code anyway didn't do anything).
LLDB frequently converts QualType to CompilerType. This is currently done like this:
result = CompilerType(this, qual_type_var.getAsOpaquePtr())
There are a few shortcomings in this current approach:
1. CompilerType's constructor takes a void* pointer so it isn't type safe.
2. We can't add any sanity checks to the CompilerType constructor (e.g. that the type
actually belongs to the passed ClangASTContext) without expanding the TypeSystem API.
3. The logic for converting QualType->CompilerType is spread out over all of LLDB so
changing it is difficult (e.g., what if we want to just pass the type ptr and not the
1type_ptr | qual_flags1 to CompilerType).
This patch adds a `ClangASTContext::GetType` function similar to the other GetTypeForDecl
functions that does this conversion in a type safe way.
It also adds a sanity check for Tag-based types that the type actually belongs to the
current ClangASTContext (Types don't seem to know their ASTContext, so we have to
workaround by looking at the decl for the underlying TagDecl. This doesn't cover all types
we construct but it's better than no sanity check).
CompilerType has no virtual functions and no statements in its constructors,
so we can simplify this code. This also allows Clang to emit unused variable warnings
for CompilerType, so I also removed one unused variable that otherwise causes -Werror
builds to fail.
We try to build a CompilerType from the persistent decls so we need
a ClangASTContext. With this patch the ClangPersistentVariables store
the associated ClangASTContext of the persistent decls (which is
always the scratch ClangASTContext) and no longer call GetASTContext
to map back from clang::ASTContext to ClangASTContext.
Instead of returning NamedDecls and then calling GetASTContext
to find back the ClangASTContext we used can just implement the
FindDecl variant that returns CompilerDecls (and implement the
other function by throwing away the ClangASTContext part of the
compiler decl).
GetASTContext is really expensive to call as it makes use of the global
mapping from ASTContext to ClangASTContext. This replaces all calls where
we already have the ClangASTContext around and don't need to call
GetASTContext again.
ClangExternalASTSourceCommon's purpose is to store a map from
Decl*/Type* to ClangASTMetadata. Usually this data is accessed
via the ClangASTContext interface which then grabs the
current ExternalASTSource of its ASTContext, tries to cast it
to ClangExternalASTSourceCommon and then accesses the metadata
map. If the casting fails the setter does nothing and the getter
returns a nullptr as if there was no known metadata for a type/decl.
This system breaks as soon as any non-LLDB ExternalASTSource is added via
a multiplexer to our existing ExternalASTSource (in which case we suddenly
loose all out metadata as the casting always fails with an ExternalASTSource
that is not inheriting from ClangExternalASTSourceCommon).
This patch moves the metadata map to the ClangASTContext. This gets
rid of all the fragile casting, the requirement that every ExternalASTSource in
LLDB has to inherit from ClangExternalASTSourceCommon and simplifies
the metadata implementation to a simple map lookup. As ClangExternalASTSourceCommon
had no other purpose than storing metadata, this patch deletes this class
and replaces all uses with clang::ExternalASTSource.
No other code changes in this commit beside the AppleObjCDeclVendor which
was the only code that did not use the ClangASTContext interface but directly
accessed the ClangExternalASTSourceCommon.
This adds a check that the ClangASTContext actually fits to the
DeclContext that we want to create a CompilerDeclContext for. If
the ClangASTContext (and its associated ASTContext) does not fit
to the DeclContext (that is, the DeclContext wasn't created by the
ASTContext), all computations using this malformed CompilerDeclContext
will yield unpredictable results.
Also fixes the only place that actually hits this assert which is the
construction of a CompilerDeclContext in ClangExpressionDeclMap
where we pass an unrelated ASTContext instead of the ASTContext
of the current expression.
I had to revert my previous change to DWARFASTParserClangTests.cpp
back to using the unsafe direct construction of CompilerDeclContext
as this assert won't work if the DeclContext we pass isn't a valid
DeclContext in the first place.
The CompilerDeclContext constructor takes a void* pointer which
means that all callers of this constructor need to first explicitly
convert all pointers to clang::DeclContext*. This causes that we
for example can't just pass a TranslationUnitDecl* to the constructor without
first casting it to its parent class (as it inherits from both
Decl and DeclContext so the void* pointer is actually a Decl*).
This patch introduces a utility function in the ClangASTContext
which gets rid of the requirement to cast all pointers to
clang::DeclContext. Also moves all constructor calls to use this
function instead which is NFC (beside the change in
DWARFASTParserClangTests.cpp).
ClangASTContext::getASTContext() currently returns a ptr but we have an assert there since a
while that the ASTContext is not a nullptr. This causes that we still have a lot of code
that is doing nullptr checks on the result of getASTContext() which is all unreachable code.
This patch changes the return value to a reference to make it clear this can't be a nullptr
and deletes all the nullptr checks.
Their naming is misleading as they only return the
ClangASTContext-owned variables. For ClangASTContext instances constructed
for a given clang::ASTContext they silently generated duplicated instances
(e.g., a second IdentifierTable) that were essentially unusable.
This removes all these getters as they are anyway not very useful in comparison
to just calling the clang::ASTContext getters. The initialization
code has been moved to the CreateASTContext initialization method so that all
code for making our own clang::ASTContext is in one place.
echo -e '#include <unistd.h>\nint main(void){\nsync();return 0;}'|./bin/clang -g -x c -;./bin/lldb -o 'file ./a.out' -o 'b main' -o r -o 'p (void)sync()'
Actual:
error: Expression can't be run, because there is no JIT compiled function
Expected:
<nothing, sync() has been executed>
This patch has been checked by:
D71707: clang-tidy: new bugprone-pointer-cast-widening
https://reviews.llvm.org/D71707
Casting from 32-bit `void *` to `uint64_t` requires an intermediate `uintptr_t` cast otherwise the pointer gets sign-extended:
echo -e '#include <stdio.h>\n#include <stdint.h>\nint main(void){void *p=(void *)0x80000000;unsigned long long ull=(unsigned long long)p;unsigned long long ull2=(unsigned long
long)(uintptr_t)p;printf("p=%p ull=0x%llx ull2=0x%llx\\n",p,ull,ull2);return 0;}'|gcc -Wall -m32 -x c -;./a.out
<stdin>: In function ‘main’:
<stdin>:3:66: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
p=0x80000000 ull=0xffffffff80000000 ull2=0x80000000
With debug output:
Actual:
IRMemoryMap::WriteMemory (0xb6ff8640, 0xffffffffb6f82158, 0x112) went to [0xb6ff8640..0xb6ff86b3)
Code can be run in the target.
Found function, has local address 0xffffffffb6f84000 and remote address 0xffffffffffffffff
Couldn't disassemble function : Couldn't find code range for function _Z12$__lldb_exprPv
Sections:
[0xb6f84000+0x3c]->0xb6ff9020 (alignment 4, section ID 0, name .text)
...
HandleCommand, command did not succeed
error: Expression can't be run, because there is no JIT compiled function
Expected:
IRMemoryMap::WriteMemory (0xb6ff8640, 0xb6faa15c, 0x128) went to [0xb6ff8640..0xb6ff86c3)
IRExecutionUnit::GetRemoteAddressForLocal() found 0xb6fac000 in [0xb6fac000..0xb6fac040], and returned 0xb6ff9020 from [0xb6ff9020..0xb6ff9060].
Code can be run in the target.
Found function, has local address 0xb6fac000 and remote address 0xb6ff9020
Function's code range is [0xb6ff9020+0x40]
...
Function data has contents:
0xb6ff9020: 10 4c 2d e9 08 b0 8d e2 08 d0 4d e2 00 40 a0 e1
...
Function disassembly:
0xb6ff9020: 0xe92d4c10 push {r4, r10, r11, lr}
Differential revision: https://reviews.llvm.org/D71498
We already pass a Decl here and the additional ASTContext needs to
match the Decl. We might as well just pass the Decl and then extract
the ASTContext from that.
This adds a unit test for looking up persistent declarations in the scratch AST
context. Also adds the `GetPersistentDecl` hook to the ClangExpressionDeclMap
that this unit test can emulate looking up persistent variables without having
a lldb_private::Target.
The ClangExpressionDeclMap should be testable from a unit test. This is currently
impossible as they have both dependencies on Target/ExecutionContext from their
constructor. This patch allows constructing these classes without an active Target
and adds the missing tests for running without a target that we can do at least
a basic lookup test without crashing.
Summary:
As discussed on the mailing list [1] we have to make a decision for how to proceed with the modern-type-lookup.
This patch removes modern-type-lookup from LLDB. This just removes all the code behind the modern-type-lookup
setting but it does *not* remove any code from Clang (i.e., the ExternalASTMerger and the clang-import-test stay around
for now).
The motivation for this is that I don't think that the current approach of implementing modern-type-lookup
will work out. Especially creating a completely new lookup system behind some setting that is never turned on by anyone
and then one day make one big switch to the new system seems wrong. It doesn't fit into the way LLVM is developed and has
so far made the transition work much more complicated than it has to be.
A lot of the benefits that were supposed to come with the modern-type-lookup are related to having a better organization
in the way types move across LLDB and having less dependencies on unrelated LLDB code. By just looking at the current code (mostly
the ClangASTImporter) I think we can reach the same goals by just incrementally cleaning up, documenting, refactoring
and actually testing the existing code we have.
[1] http://lists.llvm.org/pipermail/lldb-dev/2019-December/015831.html
Reviewers: shafik, martong
Subscribers: rnkovacs, christof, arphaman, JDevlieghere, usaxena95, lldb-commits, friss
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D71562
The overloads that don't take a CompilerType serve no purpose as we
always have a CompilerType in the scope where we call them. Instead
just call the overload that takes a CompilerType and delete the
now unused other overloaded methods.
Target doesn't really need to know about ClangASTContext more than any
other TypeSystem. We can create a method ClangASTContext::GetScratch for
anything who needs a ClangASTContext specifically instead of just a
generic TypeSystem.
Summary: Not once have I looked at these numbers in a log and considered them useful. Also this should not have been implemented via an unguarded list of globals.
Reviewers: martong, shafik
Reviewed By: shafik
Subscribers: rnkovacs, JDevlieghere, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D71336
This code was just creating a new SymbolContextList with any found functions
in the front and orders them by how close they are to the current frame.
This refactors this code into its own function to make this more obvious.
Doesn't do any other changes to the code, so this is NFC.
ClangASTSource currently takes a clang::ASTContext and keeps that
around, but a lot of LLDB's functionality for doing operations
on a clang::ASTContext is in its ClangASTContext twin class. We
currently constantly recompute the respective ClangASTContext
from the clang::ASTContext while we instead could just pass and
store a ClangASTContext in the ClangASTSource. This also allows
us to get rid of a bunch of unreachable error checking for cases
where recomputation fails for some reason.
Summary:
Adds support for doing range-based for-loops on LLDB's VariableList and
modernises all the index-based for-loops in LLDB where possible.
Reviewers: labath, jdoerfert
Reviewed By: labath
Subscribers: JDevlieghere, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D70668
Summary:
LLDB's ASTDumper is just a clone of Clang's ASTDumper but with some scary code and
some unrelated functionality (like dumping name/attributes of types). This removes LLDB's ASTDumper
and replaces its uses with the `ClangUtils::DumpDecl` method that just calls Clang's ASTDumper
and returns the result as a string.
The few uses where we just want a textual representation of a type (which will print their name/attributes but not
dump any AST) are now also in ClangUtil under a `ToString` name until we find a better home for them.
Reviewers: labath
Reviewed By: labath
Subscribers: mgorny, JDevlieghere, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D70663
