Summary:
This patch attempts to solve two issues made this code hard to follow
for me.
The first issue was that a lot of what these visitors do is mutate the
AST. The visitor pattern is not particularly good for that because by
the time you have performed the dynamic type dispatch, it's too late to
go back to the parent node, and change its pointer. The previous code
dealt with that relatively elegantly, but it still meant that one had to
perform manual type checks, which is what the visitor pattern is
supposed to avoid.
The second issue was not being able to return values from the Visit
functions, which meant that one had to store function results in member
variables (a common problem with visitor patterns).
Here, I solve both problems by making the visitor use a type switch
instead of going through double dispatch on the visited object. This
allows one to parameterize the visitor based on the return type and pass
function results as function results. The mutation is fascilitated by
having each Visit function take two arguments -- a reference to the
object itself (with the correct dynamic type), and a reference to the
parent's pointer to this object.
Although this wasn't my explicit goal here, the fact that we're not
using virtual dispatch anymore allows us to make the AST nodes
trivially destructible, which is a good thing, since we were not
destroying them anyway.
Reviewers: aleksandr.urakov, amccarth
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D60410
llvm-svn: 358261
A lot of comments in LLDB are surrounded by an ASCII line to delimit the
begging and end of the comment.
Its use is not really consistent across the code base, sometimes the
lines are longer, sometimes they are shorter and sometimes they are
omitted. Furthermore, it looks kind of weird with the 80 column limit,
where the comment actually extends past the line, but not by much.
Furthermore, when /// is used for Doxygen comments, it looks
particularly odd. And when // is used, it incorrectly gives the
impression that it's actually a Doxygen comment.
I assume these lines were added to improve distinguishing between
comments and code. However, given that todays editors and IDEs do a
great job at highlighting comments, I think it's worth to drop this for
the sake of consistency. The alternative is fixing all the
inconsistencies, which would create a lot more churn.
Differential revision: https://reviews.llvm.org/D60508
llvm-svn: 358135
Summary:
The code was passing pointers around, expecting they would be not null.
In c++ it is possible to convey this notion explicitly by using a
reference instead.
Not all uses of pointers could be converted to references (e.g. one
can't store references in a container), but this will at least make it
locally obvious that code is dealing with nonnull pointers.
Reviewers: aleksandr.urakov, amccarth
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D60271
llvm-svn: 357744
Summary:
Now CVType and CVSymbol are effectively type-safe wrappers around
ArrayRef<uint8_t>. Make the kind() accessor load it from the
RecordPrefix, which is the same for types and symbols.
Reviewers: zturner, aganea
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60018
llvm-svn: 357658
A recent patch to LLD started emitting information about import modules.
These are represented as compile units in the PDB, but with no
additional debug info. This was confusing the native pdb reader, who
expected that the debug info stream be present.
This should fix failing tests on the Windows bots.
llvm-svn: 357513
Summary:
This refactors moves the register name->number resolution out of the
FPOProgramNodeRegisterRef class. Instead I create a special
FPOProgramNodeSymbol class, which holds unresolved symbols, and move the
resolution into the ResolveRegisterRefs visitor.
The background here is that I'd like to use this code for Breakpad
unwind info, which uses similar syntax to describe unwind info. For
example, a simple breakpad unwind program might look like:
.cfa: $esp 8 + $ebp: .cfa 8 - ^
To be able to do this, I need to be able to customize register
resolving, as that is presently hardcoded to use codeview register
names, but breakpad supports a lot more architectures with different
register names. Moving the resolution into a separate class will allow
each user to use a different resolution logic.
Reviewers: aleksandr.urakov, zturner, amccarth
Subscribers: jdoerfert, lldb-commits
Differential Revision: https://reviews.llvm.org/D60068
llvm-svn: 357455
Summary:
An TranslationUnitDecl was being brought in from the clang::ASTContext
which required clang specific code to exist in SymbolFilePDB.
Since it was unused we can just get rid of it along with the clang
specific code.
Reviewers: rnk, zturner, compnerd
Reviewed By: compnerd
Subscribers: jdoerfert
Differential Revision: https://reviews.llvm.org/D59804
llvm-svn: 357113
This is diagnosed by gcc-8. The ValueType struct already has a default
constructor which performs zero-initialization, so we can just call that
instead of using memset.
llvm-svn: 357056
Summary:
Instead of assuming that the language is C++ instead check the compunit
for the language it received from the debug info.
Subscribers: aprantl, jdoerfert
Differential Revision: https://reviews.llvm.org/D59805
llvm-svn: 357044
This reverts commit r356682 because it breaks the DWO flavours of some
tests:
lldb-Suite :: lang/c/const_variables/TestConstVariables.py
lldb-Suite :: lang/c/local_variables/TestLocalVariables.py
lldb-Suite :: lang/c/vla/TestVLA.py
llvm-svn: 356773
This is mostly mechanical, and just moves the remaining non-DWO
related sections over to DWARFContext.
Differential Revision: https://reviews.llvm.org/D59611
llvm-svn: 356682
LLVM's DWARF parsing library has a class called DWARFContext which holds
all of the various DWARF data sections and lots of other information.
LLDB's on the other hand stores all of this directly in SymbolFileDWARF
/ SymbolFileDWARFDwo and passes this interface around through the
parsing library. Obviously this is incompatible with a world where the
low level interface does not depend on the high level interface, so we
need to move towards a model similar to LLVM's - i.e. all of the context
needed for low level parsing should be in a single class, and that class
gets passed around.
This patch is a small incremental step towards achieving this. The
interface and internals deviate from LLVM's for technical reasons, but
the high level idea is the same. The goal is, eventually, to remove all
occurrences of SymbolFileDWARF from the low level parsing code.
For now I've chosen a very simple section - the .debug_aranges section
to move into DWARFContext while leaving everything else unchanged. In
the short term this is a bit confusing because now the information you
need might come from either of 2 different locations. But it's a huge
refactor to do this all at once and runs a much higher risk of breaking
things. So I think it would be wise to do this in very small pieces.
TL;DR - No functional change
Differential Revision: https://reviews.llvm.org/D59562
llvm-svn: 356612
All of this is code that is unreferenced. Removing as much of
this as possible makes it more easy to determine what functionality
is missing and/or shared between LLVM and LLDB's DWARF interfaces.
llvm-svn: 356509
Most of these are Dump functions that are never called, but there
is one instance of entire unused classes (DWARFDebugMacinfo and
DWARFDebugMacinfoEntry) which are also unreferenced in the codebase).
Differential Revision: https://reviews.llvm.org/D59276
llvm-svn: 356490
These log statements have questionable value, and hinder the effort
of separating the high and low level DWARF parsing interfaces inside
of LLDB. Removing them for now, and if/when we need such log statements
again in the future, we can add them back (if possible) or introduce a
mechanism for logging from the low-level interface in such a way that it
isn't coupled to the high level interface.
Differential Revision: https://reviews.llvm.org/D59498
llvm-svn: 356469
This continues the work of introducing Error and Expected into
the DWARF parsing interfaces, this time for the DWARFCompileUnit
and DWARFDebugAranges classes.
Differential Revision: https://reviews.llvm.org/D59381
llvm-svn: 356278
The goal here is to improve our error handling and error recovery while
parsing DWARF, while at the same time getting us closer to being able to
merge LLDB's DWARF parser with LLVM's. To this end, I've udpated several
of the low-level parsing functions in LLDB to return llvm::Error and
llvm::Expected.
For now, this only updates LLDB parsing functions and not LLVM. In some
ways, this actually gets us *farther* from parity with the two
interfaces, because prior to this patch, at least the parsing interfaces
were the same (i.e. they all just returned bools, and now with this
patch they're diverging). But, I chose to do this for two primary
reasons.
LLDB has error logging code engrained deep within some of its parsing
functions. We don't want to lose this logging information, but obviously
LLVM has no logging mechanism at all. So if we're to merge the
interfaces, we have to find a way to still allow LLDB to properly report
parsing errors while not having the reporting code be inside of LLVM.
LLDB (and indeed, LLVM) overload the meaning of the false return value
from all of these extraction functions to mean both "We reached the null
entry at the end of a list of items, therefore everything was
successful" as well as "something bad and unrecoverable happened during
parsing". So you would have a lot code that would do something like:
while (foo.extract(...)) {
...
}
But when the loop stops, why did it stop? Did it stop because it
finished parsing, or because there was an error? Because of this, in
some cases we don't always know whether it is ok to proceed, or how to
proceed, but we were doing it anyway.
In this patch, I solve the second problem by introducing an
enumeration called DWARFEnumState which has two values MoreItems and
Complete. Both of these indicate success, but the latter indicates
that we reached the null entry. Then, I return this value instead of
bool, and convey parsing failure separately.
To solve the first problem (and convey parsing failure) these
functions now return either llvm::Error or llvm::Expected<DWARFEnumState>.
Having this extra bit of information allows us to properly convey all 3 of
"error, bail out", "success, call this function again", and "success,
don't call this function again".
In subsequent patches I plan to extend this pattern to the rest of the
parsing interfaces, which will ultimately get all of the log statements
and error reporting out of the low level parsing code and into the high
level parsing code (e.g. SymbolFileDWARF, DWARFASTParserClang, etc).
Eventually, these same changes will have to be backported to LLVM's
DWARF parser, but diverging in the short term is the easiest way to
converge in the long term.
Differential Revision: https://reviews.llvm.org/D59370
llvm-svn: 356190
LLVM doesn't produce DWARF64, and neither does GCC. LLDB's support
for DWARF64 is only partial, and if enabled appears to also not work.
Finally, it's untested. Removing this makes merging LLVM and
LLDB's DWARF parsing implementations simpler.
Differential Revision: https://reviews.llvm.org/D59235
llvm-svn: 355975
This is a very thin wrapper over a std::vector<DWARFDIE> and does
not seem to provide any real value over just using a container
directly.
Differential Revision: https://reviews.llvm.org/D59165
llvm-svn: 355974
This is not used outside of the private implementation of the class,
so hiding in the implementation file is a nice way of simplifying
the external interface.
Differential Revision: https://reviews.llvm.org/D59164
llvm-svn: 355973
ICF can cause multiple symbols to start at the same virtual address.
I plan to handle this shortly, but I wanted to correct the comment for
now.
Deleted an obsolete comment about adjusting the offset for the magic
number at the beginning of the debug info stream. This adjustment is
handled at a lower level now.
llvm-svn: 355943
Summary:
This patch marks the inline namespaces from DWARF as inline and also ensures that looking
up declarations now follows the lookup rules for inline namespaces.
Reviewers: aprantl, shafik, serge-sans-paille
Reviewed By: aprantl
Subscribers: eraman, jdoerfert, lldb-commits
Tags: #c_modules_in_lldb, #lldb
Differential Revision: https://reviews.llvm.org/D59198
llvm-svn: 355897
Summary: DW_OP_GNU_addr_index has been renamed as DW_OP_addrx in the standard. clang produces DW_OP_addrx tags and with this change lldb starts to process them.
Reviewers: aprantl, jingham, davide, clayborg, serge-sans-paille
Reviewed By: aprantl
Subscribers: jdoerfert, dblaikie, labath, shafik, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D59004
llvm-svn: 355629
My apologies for the large patch. With the exception of ConstString.h
itself it was entirely produced by sed.
ConstString has exactly one const char * data member, so passing a
ConstString by reference is not any more efficient than copying it by
value. In both cases a single pointer is passed. But passing it by
value makes it harder to accidentally return the address of a local
object.
(This fixes rdar://problem/48640859 for the Apple folks)
Differential Revision: https://reviews.llvm.org/D59030
llvm-svn: 355553
This was reverted because it breaks the GreenDragon bot, but
the reason for the breakage is lost, so I'm resubmitting this
now so we can find out what the problem is.
llvm-svn: 355528
Summary:
This file implements some general purpose data structures, and so it
belongs to the Utility module.
Reviewers: zturner, jingham, JDevlieghere, clayborg, espindola
Subscribers: emaste, mgorny, javed.absar, arichardson, MaskRay, lldb-commits
Differential Revision: https://reviews.llvm.org/D58970
llvm-svn: 355509
Given that we have a target named Symbols, one wonders why a
file named Symbols.cpp is not in this target. To be clear,
the functions exposed from this file are really focused on
*locating* a symbol file on a given host, which is where the
ambiguity comes in. However, it makes more sense conceptually
to be in the Symbols target. While some of the specific places
to search for symbol files might change depending on the Host,
this is not inherently true in the same way that, for example,
"accessing the file system" or "starting threads" is
fundamentally dependent on the Host.
PDBs, for example, recently became a reality on non-Windows platforms,
and it's theoretically possible that DSYMs could become a thing on non
MacOSX platforms (maybe in a remote debugging scenario). Other types of
symbol files, such as DWO, DWP, etc have never been tied to any Host
platform anyway.
After this patch, there is only one remaining dependency from
Host to Target.
Differential Revision: https://reviews.llvm.org/D58730
llvm-svn: 355032
COFF files are modelled in lldb as having one big container section
spanning the entire module image, with the actual sections being
subsections of that. In this model, the base address is simply the
address of the first byte of that section.
This also removes the hack where ObjectFilePECOFF was using the
m_file_offset field to communicate this information. Using file offset
for this purpose is completely wrong, as that is supposed to indicate
where is this ObjectFile located in the file on disk. This field is only
meaningful for fat binaries, and should normally be 0.
Both PDB plugins have been updated to use GetBaseAddress instead of
GetFileOffset.
llvm-svn: 354258
Host had a function to get the UnixSignals instance corresponding
to the current host architecture. This means that Host had to
include a file from Target. To break this dependency, just make
this a static function directly in UnixSignals. We already have
the function UnixSignals::Create(ArchSpec) anyway, so we just
need to have UnixSignals::CreateForHost() which determines which
value to pass for the ArchSpec.
The goal here is to eventually break the Host->Target->Host
circular dependency.
Differential Revision: https://reviews.llvm.org/D57780
llvm-svn: 354168
This patch properly extracts the full submodule path as well as its
search paths from DWARF import decls and passes it on to the
ClangModulesDeclVendor.
rdar://problem/47970144
Differential Revision: https://reviews.llvm.org/D58090
llvm-svn: 353961
Summary:
This is coming from the discussion in D55356 (the most interesting part
happened on the mailing list, so it isn't reflected on the review page).
In short the issue is that lldb assumes that all bytes of a module image
in memory will be backed by a "section". This isn't the case for PECOFF
files because the initial bytes of the module image will contain the
file header, which does not correspond to any normal section in the
file. In particular, this means it is not possible to implement
GetBaseAddress function for PECOFF files, because that's supposed point
to the first byte of that header.
If my (limited) understanding of how PECOFF files work is correct, then
the OS is expecded to load the entire module into one continuous chunk
of memory. The address of that chunk (+/- ASLR) is given by the "image
base" field in the COFF header, and it's size by "image size". All of
the COFF sections are then loaded into this range.
If that's true, then we can model this behavior in lldb by creating a
"container" section to represent the entire module image, and then place
other sections inside that. This would make be consistent with how MachO
and ELF files are modelled (except that those can have multiple
top-level containers as they can be loaded into multiple discontinuous
chunks of memory).
This change required a small number of fixups in the PDB plugins, which
assumed a certain order of sections within the object file (which
obivously changes now). I fix this by changing the lookup code to use
section IDs (which are unchanged) instead of indexes. This has the nice
benefit of removing spurious -1s in the plugins as the section IDs in
the pdbs match the 1-based section IDs in the COFF plugin.
Besides making the implementation of GetBaseAddress possible, this also
improves the lookup of addresses in the gaps between the object file
sections, which will now be correctly resolved as belonging to the
object file.
Reviewers: zturner, amccarth, stella.stamenova, clayborg, lemo
Reviewed By: clayborg, lemo
Subscribers: JDevlieghere, abidh, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D56537
llvm-svn: 353916
The `ap` suffix is a remnant of lldb's former use of auto pointers,
before they got deprecated. Although all their uses were replaced by
unique pointers, some variables still carried the suffix.
In r353795 I removed another auto_ptr remnant, namely redundant calls to
::get for unique_pointers. Jim justly noted that this is a good
opportunity to clean up the variable names as well.
I went over all the changes to ensure my find-and-replace didn't have
any undesired side-effects. I hope I didn't miss any, but if you end up
at this commit doing a git blame on a weirdly named variable, please
know that the change was unintentional.
llvm-svn: 353912
Summary:
This patch makes virtual bases to be added in the correct order to the bases
list. It is important because `VTableContext` (`MicrosoftVTableContext` in our
case) uses then the order of virtual bases in the list to restore the virtual
table indexes. These indexes are used then to resolve the layout of the virtual
bases.
We haven't enough information about offsets of virtual bases regarding to the
object (moreover, in a common case we can't rely on such information, see the
example here: https://reviews.llvm.org/D53506#1272306 ), but there should be
enough information to restore the layout of the virtual bases from the indexes
in runtime. After D53506 this information is used whenever possible, so there
should be no problems with virtual bases' fields reading.
Reviewers: zturner, rnk, stella.stamenova
Subscribers: abidh, teemperor, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D56904
llvm-svn: 353806
Unlike std::make_unique, which is only available since C++14,
std::make_shared is available since C++11. Not only is std::make_shared
a lot more readable compared to ::reset(new), it also performs a single
heap allocation for the object and control block.
Differential revision: https://reviews.llvm.org/D57990
llvm-svn: 353764
Summary:
This adds support for auto-detection of path style to SymbolFileBreakpad
(similar to how r351328 did the same for DWARF). We guess each file
entry separately, as we have no idea which file came from which compile
units (and different compile units can have different path styles). The
breakpad generates should have already converted the paths to absolute
ones, so this guess should be reasonable accurate, but as always with
these kinds of things, it is hard to give guarantees about anything.
In an attempt to bring some unity to the path guessing logic, I move the
guessing logic from inside SymbolFileDWARF into the FileSpec class and
have both symbol files use it to implent their desired behavior.
Reviewers: clayborg, lemo, JDevlieghere
Subscribers: aprantl, markmentovai, lldb-commits
Differential Revision: https://reviews.llvm.org/D57895
llvm-svn: 353702
Summary:
This patch teaches SymbolFileBreakpad to parse the line information in
breakpad files and present it to lldb.
The trickiest question here was what kind of "compile units" to present
to lldb, as there really isn't enough information in breakpad files to
correctly reconstruct those.
A couple of options were considered
- have the entire file be one compile unit
- have one compile unit for each FILE record
- have one compile unit for each FUNC record
The main drawback of the first approach is that all of the files would
be considered "headers" by lldb, and so they wouldn't be searched if
target.inline-breakpoint-strategy=never. The single compile unit would
also be huge, and there isn't a good way to name it.
The second approach will create mostly correct compile units for cpp
files, but it will still be wrong for headers. However, the biggest
drawback here seemed to be the fact that this can cause a compile unit
to change mid-function (for example when a function from another file is
inlined or another file is #included into a function). While I don't
know of any specific thing that would break in this case, it does sound
like a thing that we should avoid.
In the end, we chose the third option, as it didn't seem to have any
major disadvantages, though it was not ideal either. One disadvantage
here is that this generates a large number of compile units, and there
is still a question on how to name it. We chose to simply name it after
the first line record in that function. This should be correct 99.99% of
the time, though it can produce somewhat strange results if the very
first line record comes from an #included file.
Reviewers: clayborg, zturner, lemo, markmentovai
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D56595
llvm-svn: 353404
stored relative to VFRAME
Summary:
This patch makes LLDB able to retrieve proper values for function arguments and
local variables stored in PDB relative to VFRAME register.
Patch contains retrieval of corresponding FPO table entries from PDB and a
generic translator from FPO programs to DWARF expressions to get correct VFRAME
value.
Patch also improves variables-locations.test and makes this test passable on
x86.
Patch By: leonid.mashinsky
Reviewers: zturner, asmith, stella.stamenova, aleksandr.urakov
Reviewed By: zturner
Subscribers: arphaman, labath, mgorny, aprantl, JDevlieghere, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D55122
llvm-svn: 352845
