Teach LLDB to understand INLINE and INLINE_ORIGIN records in breakpad.
They have the following formats:
```
INLINE inline_nest_level call_site_line call_site_file_num origin_num [address size]+
INLINE_ORIGIN origin_num name
```
`INLNIE_ORIGIN` is simply a string pool for INLINE so that we won't have
duplicated names for inlined functions and can show up anywhere in the symbol
file.
`INLINE` follows immediately after `FUNC` represents the ranges of momery
address that has functions inlined inside the function.
Differential Revision: https://reviews.llvm.org/D113330
Since every FUNC record (in breakpad) is a compilation unit, creating the
function for the CU allows `ResolveSymbolContext` to resolve
`eSymbolContextFunction`.
Differential Revision: https://reviews.llvm.org/D113163
`DWARFASTParserClang::ParseSingleMember` turns DWARF DIEs that describe
struct/class members into their respective Clang representation (e.g.,
clang::FieldDecl). It also updates a record of where the last field
started/ended so that we can speculatively fill any holes between a field and a
bitfield with unnamed bitfield padding.
Right now we are completely ignoring 'artificial' members when parsing the DWARF
of a struct/class. The only artificial member that seems to be emitted in
practice for C/C++ seems to be the vtable pointer.
By completely skipping both the Clang AST node creation and the updating of the
last-field record, we essentially leave a hole in our layout with the size of
our artificial member. If the next member is a bitfield we then speculatively
fill the hole with an unnamed bitfield. During CodeGen Clang inserts an
artificial vtable pointer into the layout again which now occupies the same
offset as the unnamed bitfield. This later brings down Clang's
`CGRecordLowering::insertPadding` when it checks that none of the fields of the
generated record layout overlap.
Note that this is not a Clang bug. We explicitly set the offset of our fields in
LLDB and overwrite whatever Clang makes up.
Reviewed By: labath
Differential Revision: https://reviews.llvm.org/D112697
The new key/value pairs that are added to each module's stats are:
"debugInfoByteSize": The size in bytes of debug info for each module.
"debugInfoIndexTime": The time in seconds that it took to index the debug info.
"debugInfoParseTime": The time in seconds that debug info had to be parsed.
At the top level we add up all of the debug info size, parse time and index time with the following keys:
"totalDebugInfoByteSize": The size in bytes of all debug info in all modules.
"totalDebugInfoIndexTime": The time in seconds that it took to index all debug info if it was indexed for all modules.
"totalDebugInfoParseTime": The time in seconds that debug info was parsed for all modules.
Differential Revision: https://reviews.llvm.org/D112501
Front-load the first_valid_code_address check, so that we avoid creating
the function object (instead of simply refusing to use it in queries).
Differential Revision: https://reviews.llvm.org/D112310
lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp:3635:10: error: moving a local object in a return statement prevents copy elision [-Werror,-Wpessimizing-move]
return std::move(merged);
^
This patch fixes a problem introduced by clang change
https://reviews.llvm.org/D95617 and described by
https://bugs.llvm.org/show_bug.cgi?id=50076#c6, where inlined functions
omit unused parameters both in the stack trace and in `frame var`
command. With this patch, the parameters are listed correctly in the
stack trace and in `frame var` command.
Specifically, we parse formal parameters from the abstract version of
inlined functions and use those formal parameters if they are missing
from the concrete version.
Differential Revision: https://reviews.llvm.org/D110571
specifically, ignore addresses that point before the first code section.
This resurrects D87172 with several notable changes:
- it fixes a bug where the early exits in InitializeObject left
m_first_code_address "initialized" to LLDB_INVALID_ADDRESS (0xfff..f),
which caused _everything_ to be ignored.
- it extends the line table fix to function parsing as well, where it
replaces a similar check which was checking the executable permissions
of the section. This was insufficient because some
position-independent elf executables can have an executable segment
mapped at file address zero. (What makes this fix different is that it
checks for the executable-ness of the sections contained within that
segment, and those will not be at address zero.)
- It uses a different test case, with an elf file with near-zero
addresses, and checks for both line table and function parsing.
Differential Revision: https://reviews.llvm.org/D112058
This adds the `target dump typesystem'`command which dumps the TypeSystem of the
target itself (aka the 'scratch TypeSystem'). This is similar to `target modules
dump ast` which dumps the AST of lldb::Modules associated with a selected
target.
Unlike `target modules dump ast`, the new command is not a subcommand of `target
modules dump` as it's not touching the modules of a target at all. Also unlike
`target modules dump ast` I tried to keep the implementation language-neutral,
so this patch moves our Clang `Dump` to the `TypeSystem` interface so it will
also dump the state of any future/downstream scratch TypeSystems (e.g., Swift).
That's also why the command just refers to a 'typesystem' instead of an 'ast'
(which is only how Clang is necessarily modelling the internal TypeSystem
state).
The main motivation for this patch is that I need to write some tests that check
for duplicates in the ScratchTypeSystemClang of a target. There is currently no
way to check for this at the moment (beside measuring memory consumption of
course). It's probably also useful for debugging LLDB itself.
Reviewed By: labath
Differential Revision: https://reviews.llvm.org/D111936
There is no reason why this function should be returning a ConstString.
While modifying these files, I also fixed several instances where
GetPluginName and GetPluginNameStatic were returning different strings.
I am not changing the return type of GetPluginNameStatic in this patch, as that
would necessitate additional changes, and this patch is big enough as it is.
Differential Revision: https://reviews.llvm.org/D111877
Right now DWARFASTParserClang::ParseSingleMember has two parts: One part parses
Objective-C properties and the other part parses C/C++ members/Objective-C
ivars. These parts are pretty much independent of each other (with one
historical exception, see below) and in practice they parse DIEs with different
tags/attributes: `DW_TAG_APPLE_property` and `DW_TAG_member`.
I don't see a good reason for keeping the different parsing code intertwined in
a single function, so instead split out the Objective-C property parser into its
own function.
Note that 90% of this commit is just unindenting nearly all of
`ParseSingleMember` which was inside a `if (tag == DW_TAG_member)` block. I.e.,
think of the old `ParseSingleMember` function as: The rest is just moving the
property parsing code into its own function and I added the ReportError
implementation in case we fail to resolve the property type (which before was
just a silent failure).
```
lang=c++
void DWARFASTParserClang::ParseSingleMember(...) {
[...]
if (tag == DW_TAG_member) {
[...] // This huge block got unindented in this patch as the `if` above is gone.
}
if (property) {
[...] // This is the property parsing code that is now its own function.
}
}
```
There is one exception to the rule that the parsers are independent. Before 2012
Objective-C properties were encoded as `DW_TAG_member` with
`DW_AT_APPLE_property*` attributes describing the property. In 2012 this has
changed in a series of commits (see for example
c0449635b3 which updates the docs) so that
`DW_TAG_APPLE_property` is now used for properties. With the old format we first
created an ivar and afterwards used the `DW_AT_APPLE_property*` attributes to
create the respective property, but there doesn't seem to be any way to create
such debug info with any clang from the last 9 years. So this is technically not
NFC in case some finds debug info from that time and tries to use properties.
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D111632
Just moving that block inside DWARFASTParserClang::ParseChildMembers into
its own function. Also early-exiting instead of a large if when
num_attributes is 0.
This reverts commits f9aba9a5af and
035217ff51.
As explained in the original commit message, this didn't have the
intended effect of improving the common LLDB use case, but still
provided a marginal improvement for the places where LLDB creates a
scoped time with a string literal.
The reason for the revert is that this change pulls in the os/signpost.h
header in Signposts.h. The former transitively includes loader.h, which
contains a series of macro defines that conflict with MachO.h. There are
ways to work around that, but Adrian and I concluded that none of them
are worth the trade-off in complicating Signposts.h even further.
D68422 introduced `ParsedDWARFTypeAttributes` which encapsulated attribute
parsing and storage into its own small struct. This patch is doing the same for
the member type attribute parsing. One utility class is parsing normal member
attributes and the other is parsing the dedicated Objective-C property
attributes.
Right now the patch just makes the `ParseSingleMember` function a bit shorter,
but the bigger benefit is that we can now split up the function into Objective-C
property parsing and parsing of normal members (struct/class members and
Objective-C ivars). The only shared code between those two parsing logic is the
normal member attribute parsing.
Reviewed By: labath
Differential Revision: https://reviews.llvm.org/D111494
This adds support for parsing DW_AT_calling_convention in the DWARF parser.
The generic DWARF parsing code already support extracting this attribute from A
DIE and TypeSystemClang already offers a parameter to add a calling convention
to a function type (as the PDB parser supports calling convention parsing), so
this patch just converts the DWARF enum value to the Clang enum value and adds a
few tests.
There are two tests in this patch.:
* A unit test for the added DWARF parsing code that should run on all platforms.
* An API tests that covers the whole expression evaluation machinery by trying
to call functions with non-standard calling conventions. The specific subtests
are target specific as some calling conventions only work on e.g. win32 (or, if
they work on other platforms they only really have observable differences on a
specific target). The tests are also highly compiler-specific, so if GCC or
Clang tell us that they don't support a specific calling convention then we just
skip the test.
Note that some calling conventions are supported by Clang but aren't implemented
in LLVM (e.g. `pascal`), so there we just test that if this ever gets
implemented in LLVM that LLDB works too. There are also some more tricky/obscure
conventions that are left out such as the different swift* conventions, some
planned Obj-C conventions (`Preserve*`), AAPCS* conventions (as the DWARF->Clang
conversion is ambiguous for AAPCS and APPCS-VFP) and conventions only used for
OpenCL etc.
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D108629
ParseSingleMember has two large ifs around the back of it's body:
`if (!is_artificial)` and `if (member_type)`. This patch just converts those
to early-exits. The patch is NFC. It even retains the curious fact that
Objective-C properties that fail to parse are silently ignored, but now there
is at least a FIXME that points this out.
This has the nice side-effect that it can actually store the quadruple version numbers that Apple's tools are using nowadays.
rdar://82982162
Differential Revision: https://reviews.llvm.org/D111200
This commit has introduced test failures in internal google tests.
Working theory is they are caused by a genuine problem in the patch
which gets tripped by some debug info from system libraries.
Reverting while we try to reproduce the problem in a self-contained
fashion.
This reverts commit 601168e420.
Separates the methods for recursive variable parsing in function
context and non-recursive parsing of global variables.
Differential Revision: https://reviews.llvm.org/D110570
Replace misc. StringConvert uses with llvm::to_integer()
and llvm::to_float(), except for cases where further refactoring is
planned. The purpose of this change is to eliminate the StringConvert
API that is duplicate to LLVM, and less correct in behavior at the same
time.
Differential Revision: https://reviews.llvm.org/D110447
Trying to use the DIA SDK reader only to fail with "DIA SDK wasn't enabled"
isn't very useful. The native PDB reader is missing some stuff, but it's still
better than nothing.
Reduces number of lldb-check-shell test failures with LLVM_ENABLE_DIA_SDK=NO
from 27 to 15.
Differential Revision: https://reviews.llvm.org/D110172
In all these years, we haven't found a use for this function (it has
zero callers). Lets just remove the boilerplate.
Differential Revision: https://reviews.llvm.org/D109600
This patch considers the CU index entry
when reading the .debug_rnglists.dwo section.
Reviewed By: jankratochvil
Differential Revision: https://reviews.llvm.org/D107456
Fix D98289 so that it works even for 2nd..nth compilation unit
(.debug_rnglists).
Reviewed By: dblaikie, ikudrin
Differential Revision: https://reviews.llvm.org/D106466
Skeleton vs. DWO units mismatch has been fixed in D106270. As they both
have type DWARFUnit it is a bit difficult to debug. So it is better to
make it safe against future changes.
Reviewed By: kimanh, clayborg
Differential Revision: https://reviews.llvm.org/D107659
When going through the CU entries in the name index,
make sure to compare the name entry's CU
offset against the skeleton CU's offset.
Previously there would be a mismatch, since the
wrong offset was compared, and thus no suitable
entry was found.
Reviewed By: jankratochvil
Differential Revision: https://reviews.llvm.org/D106270
Summary:
In the spirit of https://reviews.llvm.org/D70846, we only return functions with
matching mangled name from Apple/DebugNamesDWARFIndex::GetFunction if
eFunctionNameTypeFull is requested.
This speeds up lookup in the presence of large amount of class methods of the
same name (a typical examples would be constructors of templates with many
instantiations or overloaded operators).
Reviewers: labath, teemperor
Reviewed By: labath, teemperor
Subscribers: aprantl, arphaman, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D73191
This patch fixes the lookup of locations in
.debug_loclists, if they are split in a .dwp file.
Mainly, we need to consider the cu index offsets.
Reviewed By: jankratochvil
Differential Revision: https://reviews.llvm.org/D107161
As pointed out in D107434 by Walter, D103172 also changed two for loops that
were actually not just iterating over some DIEs but also using the iteration
variable later on for some other things. This patch reverts the respective
faulty parts of D103172.
This change makes sure that DwarfUnit does not load a .dwo file until
necessary. I also take advantage of DWARF 5's guarantee that the first
support file is also the primary file to make it possible to create
a compile unit without loading the .dwo file.
Testcases now require Linux as it is needed for -gsplit-dwarf.
Review By: jankratochvil, dblaikie
Differential Revision: https://reviews.llvm.org/D100299
This change makes sure that DwarfUnit does not load a .dwo file until
necessary. I also take advantage of DWARF 5's guarantee that the first
support file is also the primary file to make it possible to create
a compile unit without loading the .dwo file.
Review By: jankratochvil, dblaikie
Differential Revision: https://reviews.llvm.org/D100299
This change makes sure that DwarfUnit does not load a .dwo file until
necessary. I also take advantage of DWARF 5's guarantee that the first
support file is also the primary file to make it possible to create
a compile unit without loading the .dwo file.
Review By: jankratochvil, dblaikie
Differential Revision: https://reviews.llvm.org/D100299
If we succeed at gathering global variables for a compile
unit, there is no need to fallback to generating a manual index.
Reviewed By: jankratochvil
Differential Revision: https://reviews.llvm.org/D106355
This patch adds the ability to get a DWARFDIE's children as an LLVM range.
This way we can use for range loops to iterate over them and we can use LLVM's
algorithms like `llvm::all_of` to query all children.
The implementation has to do some small shenanigans as the iterator needs to
store a DWARFDIE, but a DWARFDIE container is also a DWARFDIE so it can't return
the iterator by value. I just made the `children` getter a templated function to
avoid the cyclic dependency.
Reviewed By: #lldb, werat, JDevlieghere
Differential Revision: https://reviews.llvm.org/D103172
LLDB's DWARF parser has some heuristics for guessing and fixing up the
accessibility of C++ class/struct members after they were already created in the
internal Clang AST. The heuristic is that if a struct/class has a base class,
then it's actually a class and it's members are private unless otherwise
specified.
From what I can see this heuristic isn't sound and also unnecessary. The idea
that inheritance implies that the `class` keyword was used and the default
visibility is `private` is incorrect. Also both GCC and Clang use
`DW_TAG_structure_type` and `DW_TAG_class_type` for `struct` and `class` types
respectively, so the default visibility we infer from that information is always
correct and there is no need to fix it up.
And finally, the access specifiers we set in the Clang AST are anyway unused
within LLDB. The expression parser explicitly ignores them to give users access
to private members and there is not SBAPI functionality that exposes this
information.
This patch removes all the heuristic code for the reasons above and instead
just relies on the access values we infer from the tag kind and explicit
annotations in DWARF.
This patch is NFCI.
Reviewed By: werat
Differential Revision: https://reviews.llvm.org/D105463
C doesn't allow empty structs but Clang/GCC support them and give them a size of 0.
LLDB implements this by checking the tag kind and if it's `DW_TAG_structure_type` then
we give it a size of 0 via an empty external RecordLayout. This is done because our
internal TypeSystem is always in C++ mode (which means we would give them a size
of 1).
The current check for when we have this special case is currently too lax as types with
`DW_TAG_structure_type` can also occur in C++ with types defined using the `struct`
keyword. This means that in a C++ program with `struct Empty{};`, LLDB would return
`0` for `sizeof(Empty)` even though the correct size is 1.
This patch removes this special case and replaces it with a generic approach that just
assigns empty structs the byte_size as specified in DWARF. The GCC/Clang special
case is handles as they both emit an explicit `DW_AT_byte_size` of 0. And if another
compiler decides to use a different byte size for this case then this should also be
handled by the same code as long as that information is provided via `DW_AT_byte_size`.
Reviewed By: werat, shafik
Differential Revision: https://reviews.llvm.org/D105471
My D99653 implemented a getter GetRnglist() for m_rnglist_table.
That was confusing as the getter returns DWARFDebugRnglistTable which
contains DWARFDebugRnglist as its elements.
when dealing with -gmodules debug info.
This fixes the bot failures on Darwin.
A recent clang change (presumably https://reviews.llvm.org/D104291)
introduced a bug where .pcm files would identify themselves as
DW_LANG_C_plus_plus, but the .o that references them would identify as
DW_LANG_C_plus_plus_14. While that bug needs to be fixed, too, it
shows that the current strict comparison also isn't meaningful.
rdar://79423225
One nice feature of the os_signpost API is that format string
substitutions happen in the consumer, not the logging
application. LLVM's current Signpost class doesn't take advantage of
this though and instead always uses a static "Begin/End %s" format
string.
This patch uses variadic macros to allow the API to be used as
intended. Unfortunately, the primary use-case I had in mind (the
LLDB_SCOPED_TIMER() macro) does not get much better from this, because
__PRETTY_FUNCTION__ is *not* a macro, but a static string, so
signposts created by LLDB_SCOPED_TIMER() still use a static "%s"
format string. At least LLDB_SCOPED_TIMERF() works as intended.
This reapplies the previously reverted patch with additional include
order fixes for non-modular builds of LLDB.
Differential Revision: https://reviews.llvm.org/D103575
This converts a default constructor's member initializers into C++11
default member initializers. This patch was automatically generated with
clang-tidy and the modernize-use-default-member-init check.
$ run-clang-tidy.py -header-filter='lldb' -checks='-*,modernize-use-default-member-init' -fix
This is a mass-refactoring patch and this commit will be added to
.git-blame-ignore-revs.
Differential revision: https://reviews.llvm.org/D103483
The `lock` call directly will check for us if the `weak_ptr` is expired and
returns an invalid `shared_ptr` (which we correctly handle), so this check is
redundant.
Reviewed By: JDevlieghere
Differential Revision: https://reviews.llvm.org/D103442
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
In D98289#inline-939112 @dblaikie said:
Perhaps this could be more informative about what makes the range list
index of 0 invalid? "index 0 out of range of range list table (with
range list base 0xXXX) with offset entry count of XX (valid indexes
0-(XX-1))" Maybe that's too verbose/not worth worrying about since
this'll only be relevant to DWARF producers trying to debug their
DWARFv5, maybe no one will ever see this message in practice. Just
a thought.
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D102851
DW_AT_ranges can use DW_FORM_sec_offset (instead of DW_FORM_rnglistx).
In such case DW_AT_rnglists_base does not need to be present.
DWARF-5 spec:
"If the offset_entry_count is zero, then DW_FORM_rnglistx cannot
be used to access a range list; DW_FORM_sec_offset must be used
instead. If the offset_entry_count is non-zero, then
DW_FORM_rnglistx may be used to access a range list;"
This fix is for TestTypeCompletion.py category `dwarf` using GCC with DWARF-5.
The fix just provides GetRnglist() lazy getter for `m_rnglist_table`.
The testcase is easier to review by:
diff -u lldb/test/Shell/SymbolFile/DWARF/DW_AT_low_pc-addrx.s \
lldb/test/Shell/SymbolFile/DWARF/DW_AT_range-DW_FORM_sec_offset.s
Differential Revision: https://reviews.llvm.org/D98289
We have a bug in which using member_clang_type.GetByteSize() triggers record
layout and during this process since the record was not yet complete we ended
up reaching a record that had not been layed out yet.
Using member_type->GetByteSize() avoids this situation since it relies on size
from DWARF and will not trigger record layout.
For reference: rdar://77293040
Differential Revision: https://reviews.llvm.org/D102445
A type system is not guaranteed to have a symbol file. This patch adds null-pointer checks so we don't crash when trying to access a type system's symbol file.
Reviewed By: aprantl, teemperor
Differential Revision: https://reviews.llvm.org/D101539
This patch refactors a good part of the code base turning the usual
FileSpec, Line, Column, CheckInlines, ExactMatch arguments into a
SourceLocationSpec object.
This change is required for a following patch that will add handling of the
column line information when doing symbol resolution.
Differential Revision: https://reviews.llvm.org/D100965
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
This patch moves the Declaration class from the Symbol library to the
Core library. This will allow to use it in a more generic fashion and
aims to lower the dependency cycles when it comes to the linking.
The patch also does some cleaning up by making column information
permanent and removing the LLDB_ENABLE_DECLARATION_COLUMNS directives.
Differential revision: https://reviews.llvm.org/D101556
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
`InsertSequence` doesn't take ownership of the pointer so releasing this pointer
is just leaking memory.
Follow up to D100806 that was fixing other leak sanitizer test failures
Reviewed By: JDevlieghere
Differential Revision: https://reviews.llvm.org/D100846
DWARF allows .dwo file paths to be relative rather than absolute. When
they are relative, DWARF uses DW_AT_comp_dir to find the .dwo
file. DW_AT_comp_dir can also be relative, making the entire search
patch for the .dwo file relative. In this case, LLDB currently
searches relative to its current working directory, i.e. the directory
from which the debugger was launched. This is not right, as the
compiler, which generated the relative paths, can have no idea where
the debugger will be launched. The correct thing is to search relative
to the location of the executable binary. That is what this patch
does.
Differential Revision: https://reviews.llvm.org/D97786
DWARF allows .dwo file paths to be relative rather than absolute. When
they are relative, DWARF uses DW_AT_comp_dir to find the .dwo
file. DW_AT_comp_dir can also be relative, making the entire search
patch for the .dwo file relative. In this case, LLDB currently
searches relative to its current working directory, i.e. the directory
from which the debugger was launched. This is not right, as the
compiler, which generated the relative paths, can have no idea where
the debugger will be launched. The correct thing is to search relative
to the location of the executable binary. That is what this patch
does.
Differential Revision: https://reviews.llvm.org/D97786
When LLDB's DWARF parser is parsing the member DIEs of a struct/class it
currently fully resolves the types of static member variables in a class before
adding the respective `VarDecl` to the record.
For record types fully resolving the type will also parse the member DIEs of the
respective class. The other way of resolving is just 'forward' resolving the type
which will try to load only the minimum amount of information about the type
(for records that would only be the name/kind of the type). Usually we always
resolve types on-demand so it's rarely useful to speculatively fully resolve
them on the first use.
This patch changes makes that we only 'forward' resolve the types of static
members. This solves the fact that LLDB unnecessarily loads debug information
to parse the type if it's maybe not needed later and it also avoids a crash where
the parsed type might in turn reference the surrounding class that is currently
being parsed.
The new test case demonstrates the crash that might happen. The crash happens
with the following steps:
1. We parse class `ToLayout` and it's members.
2. We parse the static class member and fully resolve its type
(`DependsOnParam2<ToLayout>`).
3. That type has a non-static class member `DependsOnParam1<ToLayout>` for which
LLDB will try to calculate the size.
4. The layout (and size)`DependsOnParam1<ToLayout>` turns depends on the
`ToLayout` size/layout.
5. Clang will calculate the record layout/size for `ToLayout` even though we are
currently parsing it and it's missing it's non-static member.
The created is missing the offset for the yet unparsed non-static member. If we
later try to get the offset we end up hitting different asserts. Most common is
the one in `TypeSystemClang::DumpValue` where it checks that the record layout
has offsets for the current FieldDecl.
```
assert(field_idx < record_layout.getFieldCount());
```
Fixed rdar://67910011
Reviewed By: shafik
Differential Revision: https://reviews.llvm.org/D100180
If the debug info is missing the terminating null die, we would crash
when trying to access the nonexisting children/siblings. This was
discovered because the test case for D98619 accidentaly produced such
input.
Remove the "depth" variable, as the same information can be obtained
through die_index_stack.size().
Also add a test case for a one tricky case I noticed -- a unit
containing only a null unit die.
When LLVM error handling was introduced to the parsing of the .debug_aranges it would cause major issues if any DWARFDebugArangeSet::extract() calls returned any errors. The code in DWARFDebugInfo::GetCompileUnitAranges() would end up calling DWARFDebugAranges::extract() which would return an error if _any_ DWARFDebugArangeSet had any errors, but it default constructed a DWARFDebugAranges object into DWARFDebugInfo::m_cu_aranges_up and populated it partially, and returned an error prior to finishing much needed functionality in the DWARFDebugInfo::GetCompileUnitAranges() function. Subsequent callers to this function would see that the DWARFDebugInfo::m_cu_aranges_up was actually valid and return this partially populated DWARFDebugAranges reference _and_ it would not be sorted or minimized.
This above bugs would cause an incomplete .debug_aranges parsing, it would skip manually parsing any compile units for ranges, and would not sort the DWARFDebugAranges in m_cu_aranges_up.
This bug would also cause breakpoints set by file and line to fail to set correctly if a symbol context for an address could not be resolved properly, which the incomplete and unsorted DWARFDebugAranges object that DWARFDebugInfo::GetCompileUnitAranges() returned would cause symbol context lookups resolved by address (breakpoint address) to fail to find any DWARF debug info for a given address.
This patch fixes all of the issues that I found:
- DWARFDebugInfo::GetCompileUnitAranges() no longer returns a "llvm::Expected<DWARFDebugAranges &>", but just returns a "const DWARFDebugAranges &". Why? Because this code contained a fallback that would parse all of the valid DWARFDebugArangeSet objects, and would check which compile units had valid .debug_aranges set entries, and manually build an address ranges table using DWARFUnit::BuildAddressRangeTable(). If we return an error because any DWARFDebugArangeSet has any errors, then we don't do any of this code. Now we parse all DWARFDebugArangeSet objects that have no errors, if any calls to DWARFDebugArangeSet::extract() return errors, we skip that DWARFDebugArangeSet so that we can use the fallback call to DWARFUnit::BuildAddressRangeTable(). Since DWARFDebugInfo::GetCompileUnitAranges() needs to parse what it can from the .debug_aranges and build address ranges tables for any compile units that don't have any .debug_aranges sets, everything now works as expected.
- Fix an issue where a DWARFDebugArangeSet contains multiple terminator entries. The LLVM parser and llvm-dwarfdump properly warn about this because it happens with linux compilers and linkers and was the original cause of the bug I am fixing here. We now correctly warn about this issue if "log enable dwarf info" is enabled, but we continue to parse the DWARFDebugArangeSet correctly so we don't lose data that is contained in the .debug_aranges section.
- DWARFDebugAranges::extract() no longer returns a llvm::Error because we need to be able to parse all of the valid DWARFDebugArangeSet objects. It also will correctly skip a DWARFDebugArangeSet object that has errors in the middle of the stream by setting the start offsets of each DWARFDebugArangeSet to be calculated by the previous DWARFDebugArangeSet::extract() calculated offset that uses the header which contains the length of the DWARFDebugArangeSet. This means if do we run into real errors while parsing individual DWARFDebugArangeSet objects, we can continue to parse the rest of the validly encoded DWARFDebugArangeSet objects in the .debug_aranges section. This will allow LLDB to parse DWARF that contains a possibly newer .debug_aranges set format than LLDB currently supports because we will error out for the parsing of the DWARFDebugArangeSet, but be able to skip to the next DWARFDebugArangeSet object using the "DWARFDebugArangeSet.m_header.length" field to calculate the next starting offset.
Tests were added to cover all new functionality.
Differential Revision: https://reviews.llvm.org/D99401
LLDB can often appear deadlocked to users that use IDEs when it is indexing DWARF, or parsing symbol tables. These long running operations can make a debug session appear to be doing nothing even though a lot of work is going on inside LLDB. This patch adds a public API to allow clients to listen to debugger events that report progress and will allow UI to create an activity window or display that can show users what is going on and keep them informed of expensive operations that are going on inside LLDB.
Differential Revision: https://reviews.llvm.org/D97739
SymbolFileDWARF::ResolveSymbolContext is currently unaware that in DWARF5 the primary file is specified at file index 0. As a result it misses to correctly resolve the symbol context for the primary file when DWARF5 debug data is used and the primary file is only specified at index 0.
This change makes use of CompileUnit::ResolveSymbolContext to resolve the symbol context. The ResolveSymbolContext in CompileUnit has been previously already updated to reflect changes in DWARF5
and contains a more readable version. It can resolve more, but will also do a bit more work than
SymbolFileDWARF::ResolveSymbolContext (getting the Module, and going through SymbolFileDWARF::ResolveSymbolContextForAddress), however, it's mostly directed by $resolve_scope
what will be resolved, and ensures that code is easier to maintain if there's only one path.
Reviewed By: labath
Differential Revision: https://reviews.llvm.org/D98619
The idiom:
```
DeclContext::lookup_result R = DeclContext::lookup(Name);
for (auto *D : R) {...}
```
is not safe when in the loop body we trigger deserialization from an AST file.
The deserialization can insert new declarations in the StoredDeclsList whose
underlying type is a vector. When the vector decides to reallocate its storage
the pointer we hold becomes invalid.
This patch replaces a SmallVector with an singly-linked list. The current
approach stores a SmallVector<NamedDecl*, 4> which is around 8 pointers.
The linked list is 3, 5, or 7. We do better in terms of memory usage for small
cases (and worse in terms of locality -- the linked list entries won't be near
each other, but will be near their corresponding declarations, and we were going
to fetch those memory pages anyway). For larger cases: the vector uses a
doubling strategy for reallocation, so will generally be between half-full and
full. Let's say it's 75% full on average, so there's N * 4/3 + 4 pointers' worth
of space allocated currently and will be 2N pointers with the linked list. So we
break even when there are N=6 entries and slightly lose in terms of memory usage
after that. We suspect that's still a win on average.
Thanks to @rsmith!
Differential revision: https://reviews.llvm.org/D91524
Apply changes from https://reviews.llvm.org/D91014 to other places where DWARF entries are being processed.
Test case is provided by @jankratochvil.
The test is marked to run only on x64 and exclude Windows and Darwin, because the assembly is not OS-independent.
(First attempt https://reviews.llvm.org/D96778 broke the build bots)
Reviewed By: jankratochvil
Differential Revision: https://reviews.llvm.org/D97765
In DWARF v4 compile units go in .debug_info and type units go in
.debug_types. However, in v5 both kinds of units are in .debug_info.
Therefore we can't decide whether to use the CU or TU index just by
looking at which section we're reading from. We have to wait until we
have read the unit type from the header.
Differential Revision: https://reviews.llvm.org/D96194
The comment for ValueType claims that all values <1 are errors, but
not all switch statements take this into account. This patch
introduces an explicit Error case and deletes all default: cases, so
we get warned about incomplete switch coverage.
https://reviews.llvm.org/D96537
Finishing out the support (to the best of my knowledge/based on current
testing running the whole check-lldb with a clang forcibly using
DW_AT_ranges on all DW_TAG_subprograms) for this feature.
Differential Revision: https://reviews.llvm.org/D94064
gcc already produces debug info with this form
-freorder-block-and-partition
clang produces this sort of thing with -fbasic-block-sections and with a
coming-soon tweak to use ranges in DWARFv5 where they can allow greater
reuse of debug_addr than the low/high_pc forms.
This fixes the case of breaking on a function name, but leaves broken
printing a variable - a follow-up commit will add that and improve the
test case to match.
Differential Revision: https://reviews.llvm.org/D94063
In split DWARF v5 files, the DWO id is no longer in the DW_AT_GNU_dwo_id
attribute. It's in the CU header instead. This change makes lldb look in
both places.
Differential Revision: https://reviews.llvm.org/D93444
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
Prior to my patch of using the LLVM line table parsing code,
SymbolFileDWARF::ParseSupportFiles would only parse the line table
prologues to get the file list for any files that could be in the line
table.
With the old behavior, if we found the file that someone is setting the
breakpoint in in the support files list, we would get a valid index. If
we didn't, we would not look any further. So someone sets a breakpoint
one "MyFile.cpp:12" and if we find "MyFile.cpp" in the support file list
for the compile unit, then and only then would we get the entire line
table for that compile unit.
With the current behavior, no matter what, we always fully parse the
line table for all compile units any time any file and line breakpoint
is set. This creates a serious problem when debugging a large DWARF in
.o file project.
This patch re-instates the old behavior. Unfortunately it means we might
end up parsing to prologue twice, but I don't think that outweighs the
cost of trying to cache/reuse it.
Differential revision: https://reviews.llvm.org/D81589
D80519 <https://reviews.llvm.org/D80519>
added support for `DW_TAG_GNU_call_site` but
Bug 45886 <https://bugs.llvm.org/show_bug.cgi?id=45886>
found one case did not work.
There is:
0x000000b1: DW_TAG_GNU_call_site
DW_AT_low_pc (0x000000000040111e)
DW_AT_abstract_origin (0x000000cc "a")
...
0x000000cc: DW_TAG_subprogram
DW_AT_name ("a")
DW_AT_prototyped (true)
DW_AT_low_pc (0x0000000000401109)
^^^^^^^^^^^^ - here it did overwrite the 'low_pc' variable containing value 0x40111e we wanted
DW_AT_high_pc (0x0000000000401114)
DW_AT_frame_base (DW_OP_call_frame_cfa)
DW_AT_GNU_all_call_sites (true)
DW_TAG_GNU_call_site attributes order as produced by GCC:
0x000000b1: DW_TAG_GNU_call_site
DW_AT_low_pc (0x000000000040111e)
DW_AT_abstract_origin (0x000000cc "a")
clang produces the attributes in opposite order:
0x00000064: DW_TAG_GNU_call_site
DW_AT_abstract_origin (0x0000002a "a")
DW_AT_low_pc (0x0000000000401146)
Differential Revision: https://reviews.llvm.org/D81334
Summary:
The way that the support for the GNU dialect of tail call frames was
implemented in D80519 meant that the were reporting very bogus PC values
which pointed into the middle of an instruction: the -1 trick is
necessary for the address to resolve to the right function, but we
should still be reporting a more realistic PC value -- I say "realistic"
and not "real", because it's very debatable what should be the correct
PC value for frames like this.
This patch achieves that my moving the -1 from SymbolFileDWARF into the
stack frame computation code. The idea is that SymbolFileDWARF will
merely report whether it has provided an address of the instruction
after the tail call, or the address of the call instruction itself. The
StackFrameList machinery uses this information to set the "behaves like
frame zero" property of the artificial frames (the main thing this flag
does is it controls the -1 subtraction when looking up the function
address).
This required a moderate refactor of the CallEdge class, because it was
implicitly assuming that edges pointing after the call were real calls
and those pointing the the call insn were tail calls. The class now
carries this information explicitly -- it carries three mostly
independent pieces of information:
- an address of interest in the caller
- a bit saying whether this address points to the call insn or after it
- whether this is a tail call
Reviewers: vsk, dblaikie
Subscribers: aprantl, mgrang, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D81010
Summary:
The code changes are very straight-forward -- just handle both DW_AT_GNU
and DW_AT_call versions of all tags and attributes. There is just one
small gotcha: in the GNU version, DW_AT_low_pc was used both for the
"return pc" and the "call pc" values, depending on whether the tag was
describing a tail call, while the official scheme uses different
attributes for the two things.
Reviewers: vsk, dblaikie
Subscribers: lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D80519
The llvm DWARFExpression dump is nearly identical, but better -- for
example it does print a spurious space after zero-argument expressions.
Some parts of our code (variable locations) have been already switched
to llvm-based expression dumping. This switches the remainder: unwind
plans and some unit tests.
For Swift LLDB (but potentially also for module support in Clang-land)
we need a way to accumulate the path remappings produced by
Module::RegisterXcodeSDK(). In order to make this work for
SymbolFileDebugMaps, registering the search path remapping with both
modules is necessary.
Differential Revision: https://reviews.llvm.org/D79384
<rdar://problem/62750529>
When debugging from a SymbolMap the creation of CompileUnits for the
individual object files is so lazy that RegisterXcodeSDK() is not
invoked at all before the Swift TypeSystem wants to read it. This
patch fixes this by introducing an explicit
SymbolFile::ParseXcodeSDK() call that can be invoked deterministically
before the result is required.
<rdar://problem/62532151+62326862>
https://reviews.llvm.org/D79273
The dumping code is not used by anyone, and is a source of
inconsistencies with the llvm dwarf parser, as dumping is implemented at
a different level (DWARFDie) there.
The cause of this crash is relatively simple -- we are using a
SymbolFileDWARFDwo to parse a (skeleton) dwarf unit. This cause the
CompileUnit to be created with the wrong ID, which later triggers an
assertion in SymbolFile::SetCompileUnitAtIndex. The fix is also simple
-- ensure we use the right symbol file for parsing.
However, a fairly elaborate setup is needed trigger this bug, because
ParseCompileUnit is normally called very early on (and with the right
symbol file object) during the process of accessing a compile unit.
The only way this can be triggered is if the DWARF unit is
"accidentally" pulled into scope during expression evaluation
This can happen if the "this" object used for the context of an
expression is in a namespace, and that namespace is also present in
other compile units
The included test recreates this setup.
Summary:
The code in DWARFCompileUnit::BuildAddressRangeTable tries hard to avoid
relying on DW_AT_low/high_pc for compile unit range information, and
this logic is a big cause of llvm/lldb divergence in the lowest layers
of dwarf parsing code.
The implicit assumption in that code is that this information (as opposed to
DW_AT_ranges) is unreliable. However, I have not been able to verify
that assumption. It is definitely not true for all present-day
compilers (gcc, clang, icc), and it was also not the case for the
historic compilers that I have been able to get a hold of (thanks Matt
Godbolt).
All compiler included in my research either produced correct
DW_AT_ranges or .debug_aranges entries, or they produced no DW_AT_hi/lo
pc at all. The detailed findings are:
- gcc >= 4.4: produces DW_AT_ranges and .debug_aranges
- 4.1 <= gcc < 4.4: no DW_AT_ranges, no DW_AT_high_pc, .debug_aranges
present. The upper version range here is uncertain as godbolt.org does
not have intermediate versions.
- gcc < 4.1: no versions on godbolt.org
- clang >= 3.5: produces DW_AT_ranges, and (optionally) .debug_aranges
- 3.4 <= clang < 3.5: no DW_AT_ranges, no DW_AT_high_pc, .debug_aranges
present.
- clang <= 3.3: no DW_AT_ranges, no DW_AT_high_pc, no .debug_aranges
- icc >= 16.0.1: produces DW_AT_ranges
- icc < 16.0.1: no functional versions on godbolt.org (some are present
but fail to compile)
Based on this analysis, I believe it is safe to start trusting
DW_AT_low/high_pc information in dwarf as well as remove the code for
manually reconstructing range information by traversing the DIE
structure, and just keep the line table fallback. The only compilers
where this will change behavior are pre-3.4 clangs, which are almost 7
years old now. However, the functionality should remain unchanged
because we will be able to reconstruct this information from the line
table, which seems to be needed for some line-tables-only scenarios
anyway (haven't researched this too much, but at least some compilers
seem to emit DW_AT_ranges even in these situations).
In addition, benchmarks showed that for these compilers computing the
ranges via line tables is noticably faster than doing so via the DIE
tree.
Other advantages include simplifying the code base, removing some
untested code (the only test changes are recent tests with overly
reduced synthetic dwarf), and increasing llvm convergence.
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D78489
Pavel Labath wrote in D73206:
The internal representation of DebugNames and Apple indexes is fixed by
the relevant (pseudo-)standards, so we can't really change it. The
question is how to efficiently (and cleanly) convert from the internal
representation to some common thing. The conversion from AppleIndex to
DIERef is trivial (which is not surprising as it was the first and the
overall design was optimized for that). With debug_names, the situation
gets more tricky. The internal representation of debug_names uses
CU-relative DIE offsets, but DIERef wants an absolute offset. That means
the index has to do more work to produce the common representation. And
it needs to do that for all results, even though a lot of the index
users are really interested only in a single entry. With the switch to
user_id_t, _all_ indexes would have to do some extra work to encode it,
only for their users to have to immediately decode it back. Having
a iterator/callback based api would allow us to minimize the impact of
that, as it would only need to happen for the entries that are really
used. And /I think/ we could make it interface returns DWARFDies
directly, and each index converts to that using the most direct approach
available.
Jan Kratochvil:
It also makes all the callers shorter as they no longer need to fetch
DWARFDIE from DIERef (and handling if not found by ReportInvalidDIERef)
but the callers are already served DWARFDIE which they need.
In some cases the DWARFDIE had to be fetched both by callee (DWARFIndex
implementation) and caller.
Differential Revision: https://reviews.llvm.org/D77970
It removes some needless deep indentation and some redundant statements.
It prepares the code for a more clean next patch - DWARF index callbacks
D77327.
Differential Revision: https://reviews.llvm.org/D77326
Types that came from a Clang module are nested in DW_TAG_module tags
in DWARF. This patch recreates the Clang module hierarchy in LLDB and
1;95;0csets the owning module information accordingly. My primary motivation
is to facilitate looking up per-module APINotes for individual
declarations, but this likely also has other applications.
This reapplies the previously reverted commit, but without support for
ClassTemplateSpecializations, which I'm going to look into separately.
rdar://problem/59634380
Differential Revision: https://reviews.llvm.org/D75488
This is mostly useful for Swift support; it allows LLDB to substitute
a matching SDK it shipped with instead of the sysroot path that was
used at compile time.
The goal of this is to make the Xcode SDK something that behaves more
like the compiler's resource directory, as in that it ships with LLDB
rather than with the debugged program. This important primarily for
importing Swift and Clang modules in the expression evaluator, and
getting at the APINotes from the SDK in Swift.
For a cross-debugging scenario, this means you have to have an SDK for
your target installed alongside LLDB. In Xcode this will always be the
case.
rdar://problem/60640017
Differential Revision: https://reviews.llvm.org/D76471
This is a preparation for an upcoming patch which adds support for
DWARFv5 unit index sections. The patch adds tag "_EXT_" to identifiers
which reference sections that are deprecated in the DWARFv5 standard.
See D75929 for the discussion.
Differential Revision: https://reviews.llvm.org/D77141
Apparently the intention was to copy the condition above:
if (types.GetSize() >= max_matches)
break;
So that if the iteration stopped because of too many matches we do not
add even more matches in this 'Clang modules' block downward.
It was implemented by:
SymbolFileDWARF: Unconditionally scan through clang modules. NFCish
fe9eaadd68
Differential Revision: https://reviews.llvm.org/D77336
It is an obvious part of D77326.
It removes some needless deep indentation and some redundant statements.
It prepares the code for a more clean next patch - DWARF index callbacks
in D77327.
The old name was a bit misleading because the functions actually return
contributions to the corresponding sections.
Differential revision: https://reviews.llvm.org/D77302
Types that came from a Clang module are nested in DW_TAG_module tags
in DWARF. This patch recreates the Clang module hierarchy in LLDB and
sets the owning module information accordingly. My primary motivation
is to facilitate looking up per-module APINotes for individual
declarations, but this likely also has other applications.
rdar://problem/59634380
Differential Revision: https://reviews.llvm.org/D75488
When parsing DWARF and laying out bit-fields we currently don't take into account whether we have a base class or not.
Currently if the first field is a bit-field but the bit offset is due a field we inherit from a base class we currently
treat it as an unnamed bit-field and therefore add an extra field.
This fix will not check if we have a base class and assume that this offset is due to members we are inheriting from the base.
We are currently seeing asserts during codegen when debugging clang::DiagnosticOptions.
This assumption will fail in the case where the first field in the derived class in an unnamed bit-field. Fixing the first field
being an unnamed bit-field looks like it will require a larger change since we will need a way to track or discover the last field offset of the bases(s).
Differential Revision: https://reviews.llvm.org/D76808
In breakpad, only x86 (and mips) registers have a leading '$' in their
names. Arm architectures use plain register names.
Previously, lldb was assuming all registers have a '$'. Fix the code to
match the (unfortunately, inconsistent) reality.
Reland with changes: the test modified in this change originally failed
on a Debian/x86_64 builder, and I suspect the cause was that lldb looked
up the line location for an artificial frame by subtracting 1 from the
frame's address. For artificial frames, the subtraction must not happen
because the address is already exact.
---
lldb currently guesses the address to use when creating an artificial
frame (i.e., a frame constructed by determining the sequence of (tail)
calls which must have happened).
Guessing the address creates problems -- use the actual address provided
by the DW_AT_call_pc attribute instead.
Depends on D76336.
rdar://60307600
Differential Revision: https://reviews.llvm.org/D76337
This reverts commit 6905394d15. The
changed test is failing on Debian/x86_64, possibly because lldb is
subtracting an offset from the DW_AT_call_pc address used for the
artificial frame:
http://lab.llvm.org:8011/builders/lldb-x86_64-debian/builds/7171/steps/test/logs/stdio
/home/worker/lldb-x86_64-debian/lldb-x86_64-debian/llvm-project/lldb/test/API/functionalities/tail_call_frames/unambiguous_sequence/main.cpp:6:17: error: CHECK-NEXT: expected string not found in input
// CHECK-NEXT: frame #1: 0x{{[0-9a-f]+}} a.out`func3() at main.cpp:14:3 [opt] [artificial]
^
<stdin>:3:2: note: scanning from here
frame #1: 0x0000000000401127 a.out`func3() at main.cpp:13:4 [opt] [artificial]
lldb currently guesses the address to use when creating an artificial
frame (i.e., a frame constructed by determining the sequence of (tail)
calls which must have happened).
Guessing the address creates problems -- use the actual address provided
by the DW_AT_call_pc attribute instead.
Depends on D76336.
rdar://60307600
Differential Revision: https://reviews.llvm.org/D76337
Fix to get the AST we generate for function templates closer to what clang generates and expects.
We fix which FuntionDecl we are passing to CreateFunctionTemplateSpecializationInfo and we strip
template parameters from the name when creating the FunctionDecl and FunctionTemplateDecl.
These two fixes together fix asserts and ambiguous lookup issues for several cases which are added to the already existing small function template test.
This fixes issues with overloads, overloads and ADL, variadic function templates and templated operator overloads.
Differential Revision: https://reviews.llvm.org/D75761
If a producer emits a nonzero segment size, `lldb` will silently read
incorrect values and crash, or do something worse later as the tuple
size is expected to be 2, rather than 3.
Neither LLVM, nor GCC produce segmented aranges, but this dangerous case
should still be checked and handled.
Reviewed by: clayborg, labath
Differential Revision: https://reviews.llvm.org/D75925
Subscribers: lldb-commits
Tags: #lldb