This patch introduces a LLDB_SCOPED_TIMER macro to hide the needlessly
repetitive creation of scoped timers in LLDB. It's similar to the
LLDB_LOG(F) macro.
Differential revision: https://reviews.llvm.org/D93663
To get LLDB one step closer to fulfil the software redundancy requirements of
modern aircrafts, we apparently decided to have two separately maintained
implementations of `CreateTypedef` in TypeSystemClang. Let's pass on the idea of
an LLDB-powered jetliner and deleted one implementation.
On a more serious note: This function got duplicated a long time ago when the
idea of CompilerType with a backing TypeSystemClang subclass happened
(56939cb310). One implementation was supposed to
be called from CompilerType::CreateTypedef and the other has just always been
around to create typedefs. By accident one of the implementations is only used
by the PDB parser while the CompilerType::CreateTypedef backend is used by the
rest of LLDB.
We also had some patches over the year that only fixed one of the two functions
(D18099 for example only fixed up the CompilerType::CreateTypedef
implementation). D51162 and D86140 both fixed the same missing `addDecl` call
for one of the two implementations.
This patch:
* deletes the `CreateTypedefType` function as its only used by the PDB parser
and the `CreateTypedef` implementation is anyway needed as it's the backend
implementation of CompilerType.
* replaces the calls in the PDB parser by just calling the CompilerType wrapper.
* moves the documentation to the remaining function.
* moves the check for empty typedef names that was only in the deleted
implementation to the other (I don't think this fixes anything as I believe
all callers are already doing the same check).
I'll fix up the usual stuff (not using StringRef, not doing early exit) in a NFC
follow-up.
This patch is not NFC as the PDB parser now calls the function that has the fix
from D18099.
Reviewed By: labath, JDevlieghere
Differential Revision: https://reviews.llvm.org/D93382
We currently reject all templates that have either zero args or that have a
parameter pack without a name. Both cases are actually allowed in C++, so
rejecting them leads to LLDB instead falling back to a dummy 'void' type. This
leads to all kind of errors later on (most notable, variables that have such
template types appear to be missing as we can't have 'void' variables and
inheriting from such a template type will cause Clang to hit some asserts when
finding that the base class is 'void').
This just removes the too strict tests and adds a few tests for this stuff (+
some combinations of these tests with preceding template parameters).
Things that I left for follow-up patches:
* All the possible interactions with template-template arguments which seem like a whole new source of possible bugs.
* Function templates which completely lack sanity checks.
* Variable templates are not implemented.
* Alias templates are not implemented too.
* The rather strange checks that just make sure that the separate list of
template arg names and values always have the same length. I believe those
ought to be asserts, but my current plan is to move both those things into a
single list that can't end up in this inconsistent state.
Reviewed By: JDevlieghere, shafik
Differential Revision: https://reviews.llvm.org/D92425
When parsing DWARF and laying out bit-fields we don't properly take into account when they are in a union, they will all have a zero offset.
Differential Revision: https://reviews.llvm.org/D91118
I found a few cases where entries in the debug_line for a specific line of code have invalid entries (the address is outside of a code section or no section at all) and also valid entries. When this happens lldb might not set the breakpoint because the first line entry it will find in the line table might be the invalid one and since it's range is "invalid" no location is resolved. To get around this I changed the way we parse the line sequences to ignore those starting at an address under the first code segment.
Greg suggested to implement it this way so we don't need to check all sections for every line sequence.
Reviewed By: clayborg
Differential Revision: https://reviews.llvm.org/D87172
This would be reproducible in future DWZ category of the testsuite as:
Failed Tests (1):
lldb-api :: python_api/symbol-context/two-files/TestSymbolContextTwoFiles.py
Differential Revision: https://reviews.llvm.org/D91014
Current user_id_t format is:
63{isDebugTypes} 62..32{dwo || 7fffffff}
31..0 {die_offset}
while current DIERef format is (I have made up the bit positions but the
field widths do match):
63{m_section==isDebugTypes} 62{m_dwo_num_valid} 61..32{m_dwo_num}
31..0 {m_die_offset}
Proposing to change user_id_t to:
63{isDebugTypes} 62{dwo_is_valid} 61..32{dwo; 0 if !valid}
31..0 {die_offset}
There is no benefit of having 31-bits wide dwo_num in user_id_t when it
gets converted to 30-bits width in DIERef.
This patch is for future DWZ patchset which extends the dwo_is_valid bit
into a 2-bit field (normal, DWO, DWZ, DWZcommon) so that both user_id_t
and DIERef can be changed then the same way.
It would be best to somehow unify user_id_t and DIERef but I do not plan
to do that. user_id_t should probably remain a number for the Python API
compatibility while there still needs to be some class with all the
methods to access it.
SymbolFileDWARF::GetDwpSymbolFile() and SymbolFileDWARF::GetDIE use
0x3fffffff for DWP but that does not clash:
formerly:
31bits32..62:0x7fffffff = normal unit / not any DWO
31bits32..62:0x3fffffff = DWP
31bits32..62:others = DWO unit number
after this patch:
bit62=0 30bits32..61:any = normal unit / not any DWO
bit62=1 30bits32..61:0x3fffffff = DWP
bit62=1 30bits32..61:others = DWO unit number
Differential Revision: https://reviews.llvm.org/D90413
SymbolFileDWARF::GetTypes was not handling dwo correctly. The fix is
simple -- adding a GetNonSkeletonUnit call -- but I've snuck in a small
refactor as well.
LookupAddress makes no sense for DWARFTypeUnit.
Also make GetNonSkeletonUnit to preserve the called type.
Differential Revision: https://reviews.llvm.org/D89646
Only SymbolFileDWARF::ParseCompileUnit creates a CompileUnit and it uses
DWARFCompileUnit for that.
Differential Revision: https://reviews.llvm.org/D89165
This is a polymorphic class, copying it is a bad idea.
This was not a problem because most classes inheriting from it were
deleting their copy operations themselves. However, this enables us to
delete those explicit deletions, and ensure noone forgets to add them in
the future.
Add an optimal thread strategy to execute specified amount of tasks.
This strategy should prevent us from creating too many threads if we
occasionaly have an unexpectedly small amount of tasks.
Differential Revision: https://reviews.llvm.org/D87765
Code was added that used llvm error checking to parse .debug_aranges, but the error check after parsing the DWARFDebugArangesSet was reversed and was causing no error to be returned with no valid address ranges being actually used. This meant we always would fall back onto creating out own address ranges by parsing the compile unit's ranges. This was causing problems for cases where the DW_TAG_compile_unit had a single address range by using a DW_AT_low_pc and DW_AT_high_pc attribute pair (not using a DW_AT_ranges attribute), but the .debug_aranges had correct split ranges. In this case we would end up using the single range for the compile unit that encompassed all of the ranges from the .debug_aranges section and would cause address resolving issues in LLDB where address lookups would fail for certain addresses.
Differential Revision: https://reviews.llvm.org/D87626
`image dump symtab` seems to output the symbols in whatever order they appear in
the DenseMap that is used to filter out symbols with non-unique addresses. As
DenseMap is a hash map this order can change at any time so the output of this
command is pretty unstable. This also causes the `Breakpad/symtab.test` to fail
with enabled reverse iteration (which reverses the DenseMap order to find issues
like this).
This patch makes the DenseMap a std::vector and uses a separate DenseSet to do
the address filtering. The output order is now dependent on the order in which
the symbols are read (which should be deterministic). It might also avoid a bit
of work as all the work for creating the Symbol constructor parameters is only
done when we can actually emplace a new Symbol.
Reviewed By: labath
Differential Revision: https://reviews.llvm.org/D87036
Class-level static constexpr variables can have both DW_AT_const_value
(in the "declaration") and a DW_AT_location (in the "definition")
attributes. Our code was trying to handle this, but it was brittle and
hard to follow (and broken) because it was processing the attributes in
the order in which they were found.
Refactor the code to make the intent clearer -- DW_AT_location trumps
DW_AT_const_value, and fix the bug which meant that we were not
displaying these variables properly (the culprit was the delayed parsing
of the const_value attribute due to a need to fetch the variable type.
Differential Revision: https://reviews.llvm.org/D86615
This fixes several issues in handling of DW_AT_const_value attributes:
- the first is that the size of the data given by data forms does not
need to match the size of the underlying variable. We already had the
case to handle this for DW_FORM_(us)data -- this extends the handling
to other data forms. The main reason this was not picked up is because
clang uses leb forms in these cases while gcc prefers the fixed-size
ones.
- The handling of DW_AT_strp form was completely broken -- we would end
up using the pointer value as the result. I've reorganized this code
so that it handles all string forms uniformly.
- In case of a completely bogus form we would crash due to
strlen(nullptr).
Depends on D86311.
Differential Revision: https://reviews.llvm.org/D86348
This is very similar to D85968, only more elusive to since we were not
adding the typedef type to the relevant DeclContext until D86140, which
meant that the DeclContext was populated (and the relevant assertion
hit) only after importing the type into the expression ast in a
particular way.
I haven't checked whether this situation can be hit in the gmodules
case, but my money is on "yes".
Differential Revision: https://reviews.llvm.org/D86216
Parsing DWARFv5 debug_loclist offsets when a CU is parsed is weighing
down memory usage of symbolizers that don't need to parse this data at
all. There's not much benefit to caching these anyway - since they are
O(1) lookup and reading once you know where the offset list starts (and
can do bounds checking with the offset list size too).
In general, I think it might be time to start paying down some of the
technical debt of loc/loclist/range/rnglist parsing to try to unify it a
bit more.
eg:
* Currently DWARFUnit has: RangeSection, RangeSectionBase, LocSection,
LocSectionBase, LocTable, RngListTable, LoclistTableHeader (be nice if
these were all wrapped up in two variables - one for loclists, one for
rnglists)
* rnglists and loclists are handled differently (see:
LoclistTableHeader, but no RnglistTableHeader)
* maybe all these types could be less stateful - lazily parse what they
need to, even reparsing rather than caching because it doesn't seem
too expensive, for instance. (though admittedly so long as it's
constantcost/overead per compilatiton that's probably adequate)
* Maybe implementing and using a DWARFDataExtractor that can be
sub-ranged (so we could slice it up to just the single contribution) -
though maybe that's not so useful because loc/ranges need to refer to
it by absolute, not contribution-relative mechanisms
Differential Revision: https://reviews.llvm.org/D86110
CreateFunctionDeclaration should just take a StringRef. GetDeclarationName is
(only) used by CreateFunctionDeclaration so that's why now also takes a
StringRef.
With -flimit-debug-info, we can run into cases when we only have a class
as a declaration, but we do have a definition of a nested class. In this
case, clang will hit an assertion when adding a member to an incomplete
type (but only if it's adding a c++ class, and not C struct).
It turns out we already had code to handle a similar situation arising
in the -gmodules scenario. This extends the code to handle
-flimit-debug-info as well, and reorganizes bits of other code handling
completion of types to move functions doing similar things closer
together.
Differential Revision: https://reviews.llvm.org/D85968
When loading a PE/COFF target, the associated PDB file often wasn't
found. The executable module contains a path for the associated PDB
file, but people often debug from a different directory than the one
their build system uses. (This is especially common in post-mortem
and cross platform debugging.)
Suppose the COFF executable being debugged is `~/proj/foo.exe`, but
it was built elsewhere and refers to `D:\remote\build\env\foobar.pdb`,
LLDB wouldn't find it.
With this change, if no file exists at the PDB path, LLDB will look
in the executable directory for a PDB file that matches the name of
the one it expected (e.g., `~/proj/foobar.pdb`). If found, the PDB
is subject to the same matching criteria (GUIDs and age) as would
have been used had it been in the original location.
This same-directory-as-the-binary rule is commonly used by debuggers
on Windows.
Differential Review: https://reviews.llvm.org/D84815
Summary:
This effectively reverts r188124, which added code to handle
(DW_AT_)declarations of structures with some kinds of children as
definitions. The commit message claims this is a workaround for some
kind of debug info produced by gcc. However, it does not go into
specifics, so it's hard to reproduce or verify that this is indeed still a
problem.
Having this code is definitely a problem though, because it mistakenly
declares incomplete dwarf declarations to be complete. Both clang (with
-flimit-debug-info) and gcc (by default) generate DW_AT_declarations of
structs with children. This happens when full debug info for a class is
not emitted in a given compile unit (e.g. because of vtable homing), but
the class has inline methods which are used in the given compile unit.
In that case, the compilers emit a DW_AT_declaration of a class, but
add a DW_TAG_subprogram child to it to describe the inlined instance of
the method.
Even though the class tag has some children, it definitely does not
contain enough information to construct a full class definition (most
notably, it lacks any members). Keeping the class as incomplete allows
us to search for a real definition in other modules, helping the
-flimit-debug-info flow. And in case the definition is not found we can
display a error message saying that, instead of just showing an empty
struct.
Reviewers: clayborg, aprantl, JDevlieghere, shafik
Subscribers: lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D83302
This patch has no effect for C and C++. In more dynamic languages,
such as Objective-C and Swift GetByteSize() needs to call into the
language runtime, so it's important to pass one in where possible. My
primary motivation for this is some work I'm doing on the Swift
branch, however, it looks like we are also seeing warnings in
Objective-C that this may resolve. Everything in the SymbolFile
hierarchy still passes in nullptrs, because we don't have an execution
context in SymbolFile, since SymbolFile transcends processes.
Differential Revision: https://reviews.llvm.org/D84267
Currently expressions dealing with bit-fields in Objective-C objects is pretty broken. When generating debug-info for Objective-C bit-fields DW_AT_data_bit_offset has a different meaning than it does to C and C++.
When we parse the DWARF we validate bit offsets for C and C++ correctly but not for ObjC. For ObjC in some cases we end up incorrectly flagging an error and we don't generate further bit-fields in the AST.
Later on when we do a name lookup we don't find the ObjCIvarDecl in the ObjCInterfaceDecl in some cases since we never added it and then we don't go to the runtime to obtain the offset.
This will fix how we handle bit-fields for the Objective-C case and add tests to verify this fix but also to documents areas that still don't work and will be addressed in follow-up PRs.
Note: we can never correctly calculate offsets statically because of how Objective-C deals with the fragile base class issue. Which means the runtime may need to shift fields over.
Differential Revision: https://reviews.llvm.org/D83433
Summary:
With D81784, lld has started debug info resolving relocations to
garbage-collected symbols as -1 (instead of relocation addend). For an
unaware consumer this generated sequences which seemingly wrap the
address space -- their first entry was 0xfffff, but all other entries
were low numbers.
Lldb stores line sequences concatenated into one large vector, sorted by
the first entry, and searched with std::lower_bound. This resulted in
the low-value entries being placed at the end of the vector, which
utterly confused the lower_bound algorithm, and caused it to not find a
match. (Previously, these sequences would be at the start of the vector,
and normally would contain addresses that are far smaller than any real
address we want to look up, so std::lower_bound was fine.)
This patch makes lldb ignore these kinds of sequences completely. It
does that by changing the construction algorithm from iterating over the
rows (as parsed by llvm), to iterating over the sequences. This is
important because the llvm parsed performs validity checks when
constructing the sequence array, whereas the row array contains raw
data.
Reviewers: JDevlieghere, MaskRay
Differential Revision: https://reviews.llvm.org/D83957
There is a local 'class_language' veriable in DWARFASTParserClang which is named
as if it is related to the 'class_language' member of ParsedDWARFTypeAttributes.
However, it actually only has two possible enum values: 'ObjC' (which means the
current record is a Objective-C class) or 'Unknown' (which covers all other
cases).
This is confusing for the reader and also lead to some strange code where we
have several comparisons against the value "ObjC_plus_plus" (which is always
false).
This replaces the variable with either a const bool variable (if there are
multiple checks for that condition in a function) or a direct call to the
TypeSystemClang utility method for checking if it's a Objective-C
Object/Interface type.
Summary:
DWARF-parsing methods in SymbolFileDWARF which update module state
typically take the module lock. ParseCallEdgesInFunction doesn't do
this, but higher-level locking within lldb::Function (which owns the
storage for parsed call edges) is necessary.
The lack of locking could explain some as-of-yet unreproducible crashes
which occur in Function::GetTailCallingEdges(). In these crashes, the
`m_call_edges` vector is non-empty but contains a nullptr, which
shouldn't be possible. (If this vector is non-empty, it _must_ contain a
non-null unique_ptr.)
This may address rdar://55622443 and rdar://65119458.
Reviewers: jasonmolenda, friss, jingham
Subscribers: aprantl, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D83359
Summary:
Unify the code for requiring a complete type and move it into a single
place. The only functional change is that the "cannot start a definition
of an incomplete type" is upgrated from a runtime error/warning to an
lldbassert. An plain assert might also be fine, since (AFAICT) this can
only happen in case of a programmer error.
Reviewers: teemperor, aprantl, shafik
Subscribers: lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D83199
With -flimit-debug-info, we can have a definition of a class, but no
definition for some of its members. This extends the same logic we were
using for incomplete base classes to cover incomplete members too.
Test forward-declarations.s is removed as it is no longer applicable --
we don't warn anymore when encountering incomplete members as they could
be completed elsewhere. New checks added to TestLimitDebugInfo cover the
handling of incomplete members more thoroughly.
Summary:
This patch adds support for evaluation of expressions referring to types
which were compiled in -flimit-debug-info (a.k.a -fno-standalone-debug)
in clang. In this mode it's possible that the debug information needed
to fully describe a c++ type is not present in a single shared library
-- for example debug info for a base class or a member of a type can
only be found in another shared library. This situation is not
currently handled well within lldb as we are limited to searching within
a single shared library (lldb_private::Module) when searching for the
definition of these types.
The way that this patch gets around this limitation is by doing the
search at a later stage -- during the construction of the expression ast
context. This works by having the parser (currently SymbolFileDWARF, but
a similar approach is probably needed for PDBs too) mark a type as
"forcefully completed". What this means is that the parser has marked
the type as "complete" in the module ast context (as this is necessary
to e.g. derive classes from it), but its definition is not really there.
This is done via a new field on the ClangASTMetadata struct.
Later, when we are importing such a type into the expression ast, we
check this flag. If the flag is set, we try to find a better definition
for the type in other shared libraries. We do this by initiating a
new lookup for the "forcefully completed" classes, which then imports the
type from a module with a full definition.
This patch only implements this handling for base classes, but other
cases (members, array element types, etc.). The changes for that should
be fairly simple and mostly revolve around marking these types as
"forcefully completed" at an approriate time -- the importing logic is
generic already.
Another aspect, which is also not handled by this patch is viewing these
types via the "frame variable" command. This does not use the AST
importer and so it will need to handle these types on its own -- that
will be the subject of another patch.
Differential Revision: https://reviews.llvm.org/D81561
Summary:
When evaluating an expression referencing a constexpr static member variable, an
error is issued because the PDB does not specify a symbol with an address that
can be relocated against.
Rather than attempt to resolve the variable's value within the IR execution, the
values of all constants can be looked up and incorporated into the AST of the
record type as a literal, mirroring the original compiler AST.
This change applies to DIA and native PDB loaders.
Patch By: jackoalan
Reviewers: aleksandr.urakov, jasonmolenda, zturner, jdoerfert, teemperor
Reviewed By: aleksandr.urakov
Subscribers: sstefan1, lldb-commits, llvm-commits, #lldb
Tags: #lldb, #llvm
Differential Revision: https://reviews.llvm.org/D82160
Jonas Devlieghere