Commit Graph

717 Commits

Author SHA1 Message Date
Raphael Isemann 6e3b0cc2fb [lldb][NFC] Rename ClangASTContext to TypeSystemClang
Summary:
This commit renames ClangASTContext to TypeSystemClang to better reflect what this class is actually supposed to do
(implement the TypeSystem interface for Clang). It also gets rid of the very confusing situation that we have both a
`clang::ASTContext` and a `ClangASTContext` in clang (which sometimes causes Clang people to think I'm fiddling
with Clang's ASTContext when I'm actually just doing LLDB work).

I also have plans to potentially have multiple clang::ASTContext instances associated with one ClangASTContext so
the ASTContext naming will then become even more confusing to people.

Reviewers: #lldb, aprantl, shafik, clayborg, labath, JDevlieghere, davide, espindola, jdoerfert, xiaobai

Reviewed By: clayborg, labath, xiaobai

Subscribers: wuzish, emaste, nemanjai, mgorny, kbarton, MaskRay, arphaman, jfb, usaxena95, jingham, xiaobai, abidh, JDevlieghere, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D72684
2020-01-23 10:09:14 +01:00
Pavel Labath 3d7177acd7 [lldb/DWARF] Remove one more auto-dwo method
Summary:
Our DWARFUnit was automatically forwarding the requests to the split
unit when looking for a DIE by offset. llvm::DWARFUnit does not do that,
and is not likely to start doing it any time soon.

This patch deletes the this logic and updates the callers to request the
correct unit instead. While doing that, I've found a bit of duplicated
code for lookup up a function and block by address, so I've extracted
that into a helper function.

Reviewers: JDevlieghere, aprantl, clayborg, jdoerfert

Subscribers: lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D73112
2020-01-22 13:03:57 +01:00
Pavel Labath 18a96fd573 [lldb/DWARF] Fix a leak in line table construction
We were creating a bunch of LineSequence objects but never deleting
them.

This fixes the leak and changes the code to use std::unique_ptr, to make
it harder to make the same mistake again.
2020-01-21 14:44:11 +01:00
Pavel Labath 27df2d9f55 [lldb] Don't process symlinks deep inside DWARFUnit
Summary:
This code is handling debug info paths starting with /proc/self/cwd,
which is one of the mechanisms people use to obtain "relocatable" debug
info (the idea being that one starts the debugger with an appropriate
cwd and things "just work").

Instead of resolving the symlinks inside DWARFUnit, we can do the same
thing more elegantly by hooking into the existing Module path remapping
code. Since llvm::DWARFUnit does not support any similar functionality,
doing things this way is also a step towards unifying llvm and lldb
dwarf parsers.

Reviewers: JDevlieghere, aprantl, clayborg, jdoerfert

Subscribers: lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D71770
2020-01-20 13:05:00 +01:00
Unnar Freyr Erlendsson 39f1335486 Make SymbolFileDWARF::ParseLineTable use std::sort instead of insertion sort
Summary:
Motivation: When setting breakpoints in certain projects line sequences are frequently being inserted out of order.

Rather than inserting sequences one at a time into a sorted line table, store all the line sequences as we're building them up and sort and flatten afterwards.

Reviewers: jdoerfert, labath

Reviewed By: labath

Subscribers: teemperor, labath, mgrang, JDevlieghere, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D72909
2020-01-20 12:50:58 +01:00
Adrian Prantl 7b30370e5b Move the sysroot attribute from DIModule to DICompileUnit
[this re-applies c0176916a4
 with the correct commit message and phabricator link]

This addresses point 1 of PR44213.
https://bugs.llvm.org/show_bug.cgi?id=44213

The DW_AT_LLVM_sysroot attribute is used for Clang module debug info,
to allow LLDB to import a Clang module from source. Currently it is
part of each DW_TAG_module, however, it is the same for all modules in
a compile unit. It is more efficient and less ambiguous to store it
once in the DW_TAG_compile_unit.

This should have no effect on DWARF consumers other than LLDB.

Differential Revision: https://reviews.llvm.org/D71732
2020-01-17 12:55:40 -08:00
Adrian Prantl c17aee67f1 Revert "Rename DW_AT_LLVM_isysroot to DW_AT_LLVM_sysroot"
This reverts commit 12e479475a.

I accidentally landed this patch with the wrong commit message ...
2020-01-17 12:52:36 -08:00
Adrian Prantl 12e479475a Rename DW_AT_LLVM_isysroot to DW_AT_LLVM_sysroot
This is a purely cosmetic change that is NFC in terms of the binary
output. I bugs me that I called the attribute DW_AT_LLVM_isysroot
since the "i" is an artifact of GCC command line option syntax
(-isysroot is in the category of -i options) and doesn't carry any
useful information otherwise.

This attribute only appears in Clang module debug info.

Differential Revision: https://reviews.llvm.org/D71722
2020-01-17 09:36:48 -08:00
Vedant Kumar f0120556c7 [DWARF] Emit DW_AT_call_return_pc as an address
This reverts D53469, which changed llvm's DWARF emission to emit
DW_AT_call_return_pc as a function-local offset. Such an encoding is not
compatible with post-link block re-ordering tools and isn't standards-
compliant.

In addition to reverting back to the original DW_AT_call_return_pc
encoding, teach lldb how to fix up DW_AT_call_return_pc when the address
comes from an object file pointed-to by a debug map. While doing this I
noticed that lldb's support for tail calls that cross a DSO/object file
boundary wasn't covered, so I added tests for that. This latter case
exercises the newly added return PC fixup.

The dsymutil changes in this patch were originally included in D49887:
the associated test should be sufficient to test DW_AT_call_return_pc
encoding purely on the llvm side.

Differential Revision: https://reviews.llvm.org/D72489
2020-01-15 13:02:23 -08:00
Pavel Labath 4b5bc38802 [lldb/DWARF] Move location list sections into DWARFContext
These are the last sections not managed by the DWARFContext object. I
also introduce separate SectionType enums for dwo section variants, as
this is necessary for proper handling of single-file split dwarf.
2020-01-14 15:19:29 +01:00
Pavel Labath e65282deca [lldb/DWARF] Don't automatically search dwo unit attributes
This patch removes the code (deep inside DWARFDebugInfoEntry) which
automagically returned the attributes of the dwo unit DIE when asking
for the attributes of the skeleton unit.  This is fairly hacky, and not
consistent with how llvm DWARF parser operates.

Instead, I change the code the explicitly request (via
GetNonSkeletonUnit) the right unit to search (there were just two places
that needed this). If it turns out we need this more often, we can
create a utility function (external to DWARFUnit) for doing this.
2020-01-10 13:29:24 +01:00
Pavel Labath cd5da94d80 [lldb/DWARF] Fix mixed v4+v5 location lists
Summary:
Our code was expecting that a single (symbol) file contains only one
kind of location lists. This is not correct (on non-apple platforms, at
least) as a file can compile units with different dwarf versions.

This patch moves the deteremination of location list flavour down to the
compile unit level, fixing this problem. I have also tried to rougly
align the code with the llvm DWARFUnit. Fully matching the API is not
possible because of how lldb's DWARFExpression lives separately from the
rest of the DWARF code, but this is at least a step in the right
direction.

Reviewers: JDevlieghere, aprantl, clayborg

Subscribers: dblaikie, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D71751
2020-01-09 13:19:29 +01:00
Jonas Devlieghere ebcb36d4a1 Revert "[lldb] Don't process symlinks deep inside DWARFUnit"
This temporarily reverts commit 3cfb6677b2
because it breaks TestCompDirSymLink.py on macOS.
2019-12-23 18:04:29 -08:00
Pavel Labath e40ac74dac [lldb] Remove DWARFUnit::AppendDIEsWithTag
This function is not very useful, as it's forcing a materialization of
the returned DIEs, and calling it is not substantially simpler than just
iterating over the DIEs manually. Delete it, and rewrite the single
caller.
2019-12-23 15:50:30 +01:00
Pavel Labath 3cfb6677b2 [lldb] Don't process symlinks deep inside DWARFUnit
Summary:
This code is handling debug info paths starting with /proc/self/cwd,
which is one of the mechanisms people use to obtain "relocatable" debug
info (the idea being that one starts the debugger with an appropriate
cwd and things "just work").

Instead of resolving the symlinks inside DWARFUnit, we can do the same
thing more elegantly by hooking into the existing Module path remapping
code. Since llvm::DWARFUnit does not support any similar functionality,
doing things this way is also a step towards unifying llvm and lldb
dwarf parsers.

Reviewers: JDevlieghere, aprantl, clayborg, jdoerfert

Subscribers: lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D71770
2019-12-23 11:24:04 +01:00
Adrian Prantl 44b4b833ad Rename DW_AT_LLVM_isysroot to DW_AT_LLVM_sysroot
This is a purely cosmetic change that is NFC in terms of the binary
output. I bugs me that I called the attribute DW_AT_LLVM_isysroot
since the "i" is an artifact of GCC command line option syntax
(-isysroot is in the category of -i options) and doesn't carry any
useful information otherwise.

This attribute only appears in Clang module debug info.

Differential Revision: https://reviews.llvm.org/D71722
2019-12-20 13:11:17 -08:00
Johannes Altmanninger 92211bf0f1 [LLDB] Fix address computation for inline function
Summary:
Fixes PR41237 - SIGSEGV on call expression evaluation when debugging clang

When linking multiple compilation units that define the same functions,
the functions is merged but their debug info is not. This ignores debug
info entries for functions in a non-executable sections; those are
functions that were definitely dropped by the linker.

Reviewers: spyffe, clayborg, jasonmolenda

Reviewed By: clayborg

Subscribers: labath, aprantl, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D71487
2019-12-20 09:04:45 +01:00
Pavel Labath c8b74ee264 [lldb/DWARF] Add support for DW_AT_loclists_base&DW_FORM_loclistx
Summary:
This adds support for DWARF5 location lists which are specified
indirectly, via an index into the debug_loclists offset table. This
includes parsing the DW_AT_loclists_base attribute which determines the
location of this offset table, and support for new form DW_FORM_loclistx
which is used in conjuction with DW_AT_location to refer to the location
lists in this way.

The code uses the llvm class to parse the offset information, and I've
also tried to structure it similarly to how the relevant llvm
functionality works.

Reviewers: JDevlieghere, aprantl, clayborg

Subscribers: lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D71268
2019-12-11 11:06:17 +01:00
Pavel Labath 329008fdf1 [lldb] Improve/fix base address selection in location lists
Summary:
Lldb support base address selection entries in location lists was broken
for a long time. This wasn't noticed until llvm started producing these
kinds of entries more frequently with r374600.

In r374769, I made a quick patch which added sufficient support for them
to get the test suite to pass. However, I did not fully understand how
this code operates, and so the fix was not complete. Specifically, what
was lacking was the ability to handle modules which were not loaded at
their preferred load address (for instance, due to ASLR).

Now that I better understand how this code works, I've come to the
conclusion that the current setup does not provide enough information
to correctly process these entries. In the current setup the location
lists were parameterized by two addresses:
- the distance of the function start from the start of the compile unit.
  The purpose of this was to make the location ranges relative to the
  start of the function.
- the actual address where the function was loaded at. With this the
  function-start-relative ranges can be translated to actual memory
  locations.

The reason for the two values, instead of just one (the load bias) is (I
think) MachO, where the debug info in the object files will appear to be
relative to the address zero, but the actual code it refers to
can be moved and reordered by the linker. This means that the location
lists need to be "linked" to reflect the locations in the actual linked
file.

These two bits of information were enough to correctly process location
lists which do not contain base address selection entries (and so all
entries are relative to the CU base). However, they don't work with
them because, in theory two base address can be completely unrelated (as
can happen for instace with hot/cold function splitting, where the
linker can reorder the two pars arbitrarily).

To fix that, I split the first parameter into two:
- the compile unit base address
- the function start address, as is known in the object file

The new algorithm becomes:
- the location lists are processed as they were meant to be processed.
  The CU base address is used as the initial base address value. Base
  address selection entries can set a new base.
- the difference between the "file" and "load" function start addresses
  is used to compute the load bias. This value is added to the final
  ranges to get the actual memory location.

This algorithm is correct for non-MachO debug info, as there the
location lists correctly describe the code in the final executable, and
the dynamic linker can just move the entire module, not pieces of it. It
will also be correct for MachO if the static linker preserves relative
positions of the various parts of the location lists -- I don't know
whether it actually does that, but judging by the lack of base address
selection support in dsymutil and lldb, this isn't something that has
come up in the past.

I add a test case which simulates the ASLR scenario and demonstrates
that base address selection entries now work correctly here.

Reviewers: JDevlieghere, aprantl, clayborg

Subscribers: dblaikie, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D70532
2019-12-09 13:39:08 +01:00
Pavel Labath f5767e284b [lldb/DWARF] Switch to llvm debug_rnglists parser
Summary:
Our rnglist support was working only for the trivial cases (one CU),
because we only ever parsed one contribution out of the debug_rnglists
section. This means we were never able to resolve range lists for the
second and subsequent units (DW_FORM_sec_offset references came out
blang, and DW_FORM_rnglistx references always used the ranges lists from
the first unit).

Since both llvm and lldb rnglist parsers are sufficiently
self-contained, and operate similarly, we can fix this problem by
switching to the llvm parser instead. Besides the changes which are due
to variations in the interface, the main thing is that now the range
list object is a member of the DWARFUnit, instead of the entire symbol
file. This ensures that each unit can get it's own private set of range
list indices, and is consistent with how llvm's DWARFUnit does it
(overall, I've tried to structure the code the same way as the llvm
version).

I've also added a test case for the two unit scenario.

Reviewers: JDevlieghere, aprantl, clayborg

Subscribers: dblaikie, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D71021
2019-12-05 13:02:03 +01:00
Pavel Labath 57f8a998ce [lldb] Don't put compile unit name into the support file list and support DWARF5 line tables
Summary:
Lldb's "format-independent" debug info made use of the fact that DWARF
(<=4) did not use the file index zero, and reused the support file index
zero for storing the compile unit name.

While this provided some convenience for DWARF<=4, it meant that the PDB
plugin needed to artificially remap file indices in order to free up
index 0. Furthermore, DWARF v5 make file index 0 legal, which meant that
similar remapping would be needed in the dwarf plugin too.

What this patch does instead is remove the requirement of having the
compile unit name in the index 0. It is not that useful since the name
can always be fetched from the CompileUnit object. Remapping code in the
pdb plugin(s) has been removed or simplified.

DWARF plugin has started inserting an empty FileSpec at index 0 to
ensure the indices keep matching up (in case of DWARF<=4). For DWARF5,
we insert the file 0 from the line table.

I add a test to ensure we can correctly lookup line table entries
referencing file 0, and in particular the case where the file 0 is also
duplicated in another file entry, as this is how clang produces line
tables in some circumstances (see pr44170). Though this is probably a
bug in clang, this is not forbidden by DWARF, and lldb already has
support for that in some (but not all) cases -- this adds a test for the
code path which was not fixed in this patch.

Reviewers: clayborg, JDevlieghere, jdoerfert

Subscribers: aprantl, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D70954
2019-12-05 11:37:18 +01:00
Pavel Labath 532290e69f [lldb] s/FileSpec::Equal/FileSpec::Match
Summary:
The FileSpec class is often used as a sort of a pattern -- one specifies
a bare file name to search, and we check if in matches the full file
name of an existing module (for example).

These comparisons used FileSpec::Equal, which had some support for it
(via the full=false argument), but it was not a good fit for this job.

For one, it did a symmetric comparison, which makes sense for a function
called "equal", but not for typical searches (when searching for
"/foo/bar.so", we don't want to find a module whose name is just
"bar.so"). This resulted in patterns like:
    if (FileSpec::Equal(pattern, file, pattern.GetDirectory()))
which would request a "full" match only if the pattern really contained
a directory. This worked, but the intended behavior was very unobvious.

On top of that, a lot of the code wanted to handle the case of an
"empty" pattern, and treat it as matching everything. This resulted in
conditions like:
    if (pattern && !FileSpec::Equal(pattern, file, pattern.GetDirectory())
which are nearly impossible to decipher.

This patch introduces a FileSpec::Match function, which does exactly
what most of FileSpec::Equal callers want, an asymmetric match between a
"pattern" FileSpec and a an actual FileSpec. Empty paterns match
everything, filename-only patterns match only the filename component.

I've tried to update all callers of FileSpec::Equal to use a simpler
interface. Those that hardcoded full=true have been changed to use
operator==. Those passing full=pattern.GetDirectory() have been changed
to use FileSpec::Match.

There was also a handful of places which hardcoded full=false. I've
changed these to use FileSpec::Match too. This is a slight change in
semantics, but it does not look like that was ever intended, and it was
more likely a result of a misunderstanding of the "proper" way to use
FileSpec::Equal.

[In an ideal world a "FileSpec" and a "FileSpec pattern" would be two
different types, but given how widespread FileSpec is, it is unlikely
we'll get there in one go. This at least provides a good starting point
by centralizing all matching behavior.]

Reviewers: teemperor, JDevlieghere, jdoerfert

Subscribers: emaste, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D70851
2019-12-04 10:42:32 +01:00
Pavel Labath 38870af859 [lldb] Remove FileSpec->CompileUnit inheritance
Summary:
CompileUnit is a complicated class. Having it be implicitly convertible
to a FileSpec makes reasoning about it even harder.

This patch replaces the inheritance by a simple member and an accessor
function. This avoid the need for casting in places where one needed to
force a CompileUnit to be treated as a FileSpec, and does not add much
verbosity elsewhere.

It also fixes a bug where we were wrongly comparing CompileUnit& and a
CompileUnit*, which compiled due to a combination of this inheritance
and the FileSpec*->FileSpec implicit constructor.

Reviewers: teemperor, JDevlieghere, jdoerfert

Subscribers: lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D70827
2019-11-29 11:44:45 +01:00
Vedant Kumar 4fdbc0728d [DWARF] Handle call sites with indirect call targets
Split CallEdge into DirectCallEdge and IndirectCallEdge. Teach
DWARFExpression how to evaluate entry values in cases where the current
activation was created by an indirect call.

rdar://57094085

Differential Revision: https://reviews.llvm.org/D70100
2019-11-22 11:50:22 -08:00
Adrian Prantl 1cbe003894 [-gmodules] Let LLDB log a warning if the Clang module hash mismatches.
This feature is mostly there to aid debugging of Clang module issues,
since the only useful actual the end-user can to is to recompile their
program.

Differential Revision: https://reviews.llvm.org/D70272
2019-11-15 11:52:13 -08:00
Adrian Prantl 7d71dd928d Add RTTI support to the SymbolFile class hierarchy
Differential Revision: https://reviews.llvm.org/D70322
2019-11-15 11:52:13 -08:00
Adrian Prantl dcb5bd9109 Fix incorrect comment. 2019-11-14 09:55:24 -08:00
Adrian Prantl 268e11f95d Convert condition to early exit (NFC) 2019-11-14 09:38:49 -08:00
Adrian Prantl 0352007fdb Convert UpdateExternalModuleListIfNeeded to use early exits. 2019-11-14 09:35:06 -08:00
Adrian Prantl 0e45e60c6f Use ForEachExternalModule in ParseTypeFromClangModule (NFC)
I wanted to further simplify ParseTypeFromClangModule by replacing the
hand-rolled loop with ForEachExternalModule, and then realized that
ForEachExternalModule also had the problem of visiting the same leaf
node an exponential number of times in the worst-case. This adds a set
of searched_symbol_files set to the function as well as the ability to
early-exit from it.

Differential Revision: https://reviews.llvm.org/D70215
2019-11-14 08:58:31 -08:00
Pavel Labath 6e3ecd1884 [lldb] Fix dwo variant of TestLibCxxFunction
The test was failing due to a bug in SymbolFileDWARF::FindFunctions --
the function was searching the main dwarf unit for DW_TAG_subprograms,
but the main unit is empty in case of split dwarf.  The fix is simple --
search the non-skeleton unit instead.

This bug went unnoticed because this function is expensive, and so one
generally avoids calling it.
2019-11-14 16:29:36 +01:00
Adrian Prantl 3d30c142e1 Rename clang-module-related *DWO* functions to *ClangModule* (NFC)
This avoids confusing them with fission-related functionality.

I also moved two accessor functions from DWARFDIE into static
functions in DWARFASTParserClang were their only use is located.
2019-11-13 14:07:20 -08:00
shafik 91e94a7015 [LLDB][Formatters] Re-enable std::function formatter with fixes to improve non-cached lookup performance
Performance issues lead to the libc++ std::function formatter to be disabled. We addressed some of those performance issues by adding caching see D67111
This PR fixes the first lookup performance by not using FindSymbolsMatchingRegExAndType(...) and instead finding the compilation unit the std::function wrapped callable should be in and then searching for the callable directly in the CU.

Differential Revision: https://reviews.llvm.org/D69913
2019-11-12 11:30:18 -08:00
Adrian Prantl 3b73dcdc96 Performance: Add a set of visited SymbolFiles to the other FindFiles variant.
This is basically the same bug as in r260434.

SymbolFileDWARF::FindTypes has exponential worst-case when digging
through dependency DAG of .pcm files because each object file and .pcm
file may depend on an already-visited .pcm file, which may again have
dependencies. Fixed here by carrying a set of already visited
SymbolFiles around.

rdar://problem/56993424

Differential Revision: https://reviews.llvm.org/D70106
2019-11-12 09:38:37 -08:00
Adrian Prantl da83e96273 Fix a regression in macOS-style path remapping.
When we switched to the LLVM .debug_line parser, the .dSYM-style path
remapping logic stopped working for relative paths because of how
RemapSourceFile silently fails for relative paths. This patch both
makes the code more readable and fixes this particular bug.

One interesting thing I learned is that Module::RemapSourceFile() is a
macOS-only code path that operates on on the lldb::Module level and is
completely separate from target.source-map, which operates on a
per-Target level.

Differential Revision: https://reviews.llvm.org/D70037

rdar://problem/56924558
2019-11-11 12:21:38 -08:00
Adrian Prantl 1ad655e255 Modernize the rest of the Find.* API (NFC)
This patch removes the size_t return value and the append parameter
from the remainder of the Find.* functions in LLDB's internal API. As
in the previous patches, this is motivated by the fact that these
parameters aren't really used, and in the case of the append parameter
were frequently implemented incorrectly.

Differential Revision: https://reviews.llvm.org/D69119

llvm-svn: 375160
2019-10-17 19:56:40 +00:00
Shafik Yaghmour 5f46982b45 [lldb-test] Modify lldb-test to print out ASTs from symbol file
Summary:
Currently when invoking lldb-test symbols -dump-ast it parses all the debug symbols and calls print(...) on the TranslationUnitDecl.
While useful the TranslationUnitDecl::print(...) method gives us a higher level view then the dump from ASTDumper which is what we get when we invoke dump() on a specific AST node.
The main motivation for this change is allow us to verify that the AST nodes we create when we parse DWARF. For example in order to verify we are correctly using DIFlagExportSymbols added by D66667

Differential Revision: https://reviews.llvm.org/D67994

llvm-svn: 374570
2019-10-11 16:36:20 +00:00
Vedant Kumar 40a1853c49 [DWARFASTParserClang] Factor out structure-like type parsing, NFC
Split out the logic to parse structure-like types into a separate
function, in an attempt to reduce the complexity of ParseTypeFromDWARF.

Inspired by discussion in https://reviews.llvm.org/D68130.

Differential Revision: https://reviews.llvm.org/D68422

llvm-svn: 373927
2019-10-07 17:22:53 +00:00
Adrian Prantl bf9d84c014 Remove size_t return parameter from FindTypes
In r368345 I accidentally introduced a regression that would
over-report the number of matches found by FindTypes if the
DeclContext Filter was hit.

This patch simply removes the size_t return parameter altogether —
it's not that useful.

rdar://problem/55500457

Differential Revision: https://reviews.llvm.org/D68169

llvm-svn: 373344
2019-10-01 15:40:41 +00:00
Adrian Prantl d4d428ef92 Remove unused "append" parameter from FindTypes API
I noticed that SymbolFileDWARFDebugMap::FindTypes was implementing it
incorrectly (passing append=false in a for-loop to recursive calls to
FindTypes would yield only the very last set of results), but instead
of fixing it, removing it seemed like an even better option.

rdar://problem/54412692

Differential Revision: https://reviews.llvm.org/D68171

llvm-svn: 373224
2019-09-30 16:42:28 +00:00
Jonas Devlieghere 5e9cdeed77 [Dwarf] Fix switch cases that take an dw_tag_t.
Now that dw_tag_t is an enum, a default case is required.

llvm-svn: 372920
2019-09-25 20:59:56 +00:00
Pavel Labath 13a4e8f3ef Enhance SymbolFileDWARF::ParseDeclsForContext performance
This implements
DWARFASTParserClang::EnsureAllDIEsInDeclContextHaveBeenParsed so as to
provide a faster way to ensure all DIEs linked to a certain declaration
context have been parsed.

Currently, we rely on SymbolFileDWARF::ParseDeclsForContext calling
DWARFASTParserClang::GetDIEForDeclContext, and only then
DWARFASTParserClang::GetDeclForUIDFromDWARF. This change shortcuts that
logic and removes redundant calls to DWARFASTParserClang::
GetClangDeclForDIE by deleting DIEs from the m_decl_ctx_to_die map once
they have been parsed.

Differential Revision: https://reviews.llvm.org/D67760
Patch by Guilherme Andrade <guiandrade@google.com>.

llvm-svn: 372744
2019-09-24 12:36:54 +00:00
Raphael Isemann 9379d19ff8 [lldb] Decouple importing the std C++ module from the way the program is compiled
Summary:
At the moment, when trying to import the `std` module in LLDB, we look at the imported modules used in the compiled program
and try to infer the Clang configuration we need from the DWARF module-import. That was the initial idea but turned out to
cause a few problems or inconveniences:

* It requires that users compile their programs with C++ modules. Given how experimental C++ modules are makes this feature inaccessible
for many users. Also it means that people can't just get the benefits of this feature for free when we activate it by default
(and we can't just close all the associated bug reports).
* Relying on DWARF's imported module tags (that are only emitted by default on macOS) means this can only be used when using DWARF (and with -glldb on Linux).
* We essentially hardcoded the C standard library paths on some platforms (Linux) or just couldn't support this feature on other platforms (macOS).

This patch drops the whole idea of looking at the imported module DWARF tags and instead just uses the support files of the compilation unit.
If we look at the support files and see file paths that indicate where the C standard library and libc++ are, we can just create the module
configuration this information. This fixes all the problems above which means we can enable all the tests now on Linux, macOS and with other debug information
than what we currently had. The only debug information specific code is now the iteration over external type module when -gmodules is used (as `std` and also the
`Darwin` module are their own external type module with their own files).

The meat of this patch is the CppModuleConfiguration which looks at the file paths from the compilation unit and then figures out the include paths
based on those paths. It's quite conservative in that it only enables modules if we find a single C library and single libc++ library. It's still missing some
test mode where we try to compile an expression before we actually activate the config for the user (which probably also needs some caching mechanism),
but for now it works and makes the feature usable.

Reviewers: aprantl, shafik, jdoerfert

Reviewed By: aprantl

Subscribers: mgorny, abidh, JDevlieghere, lldb-commits

Tags: #c_modules_in_lldb, #lldb

Differential Revision: https://reviews.llvm.org/D67760

llvm-svn: 372716
2019-09-24 10:08:18 +00:00
Vedant Kumar 21d417dc18 [DWARF] Evaluate DW_OP_entry_value
Add support for evaluating DW_OP_entry_value. This involves parsing
DW_TAG_call_site_parameter and wiring the information through to the expression
evaluator.

rdar://54496008

Differential Revision: https://reviews.llvm.org/D67376

llvm-svn: 371668
2019-09-11 21:23:45 +00:00
Pavel Labath ef82098a80 Remove DWARFExpression::LocationListSize
Summary:
The only reason for this function's existance is so that we could pass
the correct size into the DWARFExpression constructor. However, there is
no harm in passing the entire data extractor into the DWARFExpression,
since the same code is performing the size determination as well as the
subsequent parse. So, if we get malformed input or there's a bug in the
parser, we'd compute the wrong size anyway.

Additionally, reducing the number of entry points into the location list
parsing machinery makes it easier to switch the llvm debug_loc(lists)
parsers.

While inside, I added a couple of tests for invalid location list
handling.

Reviewers: JDevlieghere, clayborg

Subscribers: aprantl, javed.absar, kristof.beyls, lldb-commits

Differential Revision: https://reviews.llvm.org/D66789

llvm-svn: 370373
2019-08-29 15:21:26 +00:00
Pavel Labath e588b8b664 DWARFExpression: Simplify class interface
Summary:
The DWARFExpression methods have a lot of arguments. This removes two of
them by removing the ability to slice the expression via two offset+size
parameters. This is a functionality that it is not always needed, and
when it is, we already have a different handy way of slicing a data
extractor which we can use instead.

Reviewers: JDevlieghere, clayborg

Subscribers: aprantl, lldb-commits

Differential Revision: https://reviews.llvm.org/D66745

llvm-svn: 370027
2019-08-27 07:49:41 +00:00
Adrian Prantl aa97a89d83 Extend FindTypes with CompilerContext to allow filtering by language.
This patch is also motivated by the Swift branch and is effectively NFC for the single-TypeSystem llvm.org branch.

In multi-language projects it is extremely common to have, e.g., a
Clang type and a similarly-named rendition of that same type in
another language. When searching for a type It is much cheaper to pass
a set of supported languages to the SymbolFile than having it
materialize every result and then rejecting the materialized types
that have the wrong language.

Differential Revision: https://reviews.llvm.org/D66546

<rdar://problem/54471165>

This reapplies r369690 with a previously missing constructor for LanguageSet.

llvm-svn: 369710
2019-08-22 21:45:58 +00:00
Adrian Prantl b041602e3f Revert Extend FindTypes with CompilerContext to allow filtering by language.
This reverts r369690 (git commit aa3a564efa)

llvm-svn: 369702
2019-08-22 20:41:16 +00:00
Adrian Prantl aa3a564efa Extend FindTypes with CompilerContext to allow filtering by language.
This patch is also motivated by the Swift branch and is effectively NFC for the single-TypeSystem llvm.org branch.

In multi-language projects it is extremely common to have, e.g., a
Clang type and a similarly-named rendition of that same type in
another language. When searching for a type It is much cheaper to pass
a set of supported languages to the SymbolFile than having it
materialize every result and then rejecting the materialized types
that have the wrong language.

Differential Revision: https://reviews.llvm.org/D66546

<rdar://problem/54471165>

llvm-svn: 369690
2019-08-22 19:24:55 +00:00
Adrian Prantl 330ae19a1a Generalize FindTypes with CompilerContext to support fuzzy lookup
This patch generalizes the FindTypes with CompilerContext interface to
support looking up a type of unknown kind by name, as well as looking
up a type inside an unspecified submodule. These features are
motivated by the Swift branch, but are fully tested via unit tests and
lldb-test on llvm.org.  Specifically, this patch adds an AnyModule and
an AnyType CompilerContext kind.

Differential Revision: https://reviews.llvm.org/D66507

rdar://problem/54471165

llvm-svn: 369555
2019-08-21 18:06:56 +00:00
Adrian Prantl 69cef325a3 Simplify code (NFC).
llvm-svn: 369179
2019-08-17 00:38:58 +00:00
Jonas Devlieghere de0ce98abe [DebugLine] Don't try to guess the path style
In r368879 I made an attempt to guess the path style from the files in
the line table. After some consideration I now think this is a poor
idea. This patch undoes that behavior and instead adds an optional
argument to specify the path style. This allows us to make that decision
elsewhere where we have more information. In case of LLDB based on the
Unit.

llvm-svn: 369072
2019-08-15 23:53:15 +00:00
Jonas Devlieghere a8f3ae7c9c [LLDB] Migrate llvm::make_unique to std::make_unique
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.

Differential revision: https://reviews.llvm.org/D66259

llvm-svn: 368933
2019-08-14 22:19:23 +00:00
Jordan Rupprecht 4ee1376dc6 [lldb][NFC] Remove unused function
llvm-svn: 368904
2019-08-14 19:31:56 +00:00
Jonas Devlieghere c0a9b1edca [DebugLine] Improve path handling.
After switching over LLDB's line table parser to libDebugInfo, we
noticed two regressions on the Windows bot. The problem is that when
obtaining a file from the line table prologue, we append paths without
specifying a path style. This leads to incorrect results on Windows for
debug info containing Posix paths:

  0x0000000000201000: /tmp\b.c, is_start_of_statement = TRUE

This patch is an attempt to fix that by guessing the path style whenever
possible.

Differential revision: https://reviews.llvm.org/D66227

llvm-svn: 368879
2019-08-14 17:00:10 +00:00
Jonas Devlieghere 3cb3aa2ee8 [DebugLine] Be more robust in geussing the path style
My previous change didn't fix the Windows bot. This patch is an attempt
to make guessing the path style more robust by first looking at the
compile dir and falling back to the actual file if that's unsuccessful.

llvm-svn: 368772
2019-08-13 23:30:11 +00:00
Jonas Devlieghere 4d82fa6895 [DWARF] Guess the path style
Try to guess the FileSpec path style before defaulting to native.

llvm-svn: 368746
2019-08-13 21:00:27 +00:00
Jonas Devlieghere 235339357d [DWARF} Use LLVM's debug line parser in LLDB.
The line number table header was substantially revised in DWARF 5 and is
not fully supported by LLDB's current debug line implementation.

This patch replaces the LLDB debug line parser with its counterpart in
LLVM. This was possible because of the limited contact surface between
the code to parse the DWARF debug line section and the rest of LLDB.

We pay a small cost in terms of performance and memory usage. This is
something we plan to address in the near future.

Differential revision: https://reviews.llvm.org/D62570

llvm-svn: 368742
2019-08-13 19:51:51 +00:00
Adrian Prantl fe9eaadd68 SymbolFileDWARF: Unconditionally scan through clang modules. NFCish
When looking up a type by name, also scan through any referenced Clang
modules regardsless of whether a type with this name has been
found. This is NFCish (= a potential performance regression) for Clang
projects, but necessary in mixed Swift and Objective-C projects (and
tested in swift-lldb).

This only affects projects compiled with -gmodules that were not run
through dsymutil.

llvm-svn: 368345
2019-08-08 21:16:01 +00:00
Pavel Labath 465eae3669 SymbolVendor: Remove passthrough methods
After the recent refactorings the SymbolVendor passthrough no longer
serve any purpose. This patch removes those methods, and updates all
callsites to go to the symbol file directly -- in most cases that just
means calling GetSymbolFile()->foo() instead of
GetSymbolVendor()->foo().

llvm-svn: 368001
2019-08-06 09:12:42 +00:00
Pavel Labath 23f70e8359 SymbolVendor: Introduce Module::GetSymbolFile
Summary:
This is the next step in avoiding funneling all SymbolFile calls through
the SymbolVendor. Right now, it is just a convenience function, but it
allows us to update all calls to SymbolVendor functions to access the
SymbolFile directly. Once all call sites have been updated, we can
remove the GetSymbolVendor member function.

This patch just updates the calls to GetSymbolVendor, which were calling
it just so they could fetch the underlying symbol file. Other calls will
be done in follow-ups.

Reviewers: JDevlieghere, clayborg, jingham

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D65435

llvm-svn: 367664
2019-08-02 08:16:35 +00:00
Pavel Labath d2deeb4490 SymbolVendor: Remove the object file member variable
Summary:
The last responsibility of the SymbolVendor was to hold an owning
reference to the object file (in case symbols are being read from a
different file than the main module). As SymbolFile classes already hold
a non-owning reference to the object file, we can easily remove this
responsibility of the SymbolVendor by making the SymbolFile reference
owning.

Reviewers: JDevlieghere, clayborg, jingham

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D65401

llvm-svn: 367392
2019-07-31 08:25:25 +00:00
Alex Langford 0e252e38ef [Symbol] Use llvm::Expected when getting TypeSystems
Summary:
This commit achieves the following:
- Functions used to return a `TypeSystem *` return an
  `llvm::Expected<TypeSystem *>` now. This means that the result of a call
  is always checked, forcing clients to move more carefully.
- `TypeSystemMap::GetTypeSystemForLanguage` will either return an Error or a
  non-null pointer to a TypeSystem.

Reviewers: JDevlieghere, davide, compnerd

Subscribers: jdoerfert, lldb-commits

Differential Revision: https://reviews.llvm.org/D65122

llvm-svn: 367360
2019-07-30 22:12:34 +00:00
Alex Langford 0723173114 [SymbolFile] SymbolFileDWARF::ParseLineTable should lock its module
As of svn rL367298, SymbolFileDWARF locks the module in many cases where
it needs to parse some aspect of the DWARF symbol file.
SymbolFileDWARF::ParseLineTable needs to lock the module because
SymbolVendor::ParseLineTable no longer locks it.

llvm-svn: 367358
2019-07-30 21:22:17 +00:00
Pavel Labath 656ddeb2b7 SymbolVendor: Move locking into the Symbol Files
Summary:
The last bit of functionality in SymbolVendor passthrough functions is
the locking the module mutex. While it may be nice doing the locking in
a central place, we weren't really succesful in doing that right now,
because some SymbolFile function could still be called without going
through the SymbolVendor. This meant in SymbolFileDWARF (the only
battle-tested symbol file implementation) roughly a half of the
functions was taking additional locks and another half was asserting
that the lock is already held. By making the SymbolFile responsible for
locking, we can at least make the situation in SymbolFileDWARF more
consistent.

Reviewers: clayborg, JDevlieghere, jingham, jdoerfert

Subscribers: aprantl, lldb-commits

Differential Revision: https://reviews.llvm.org/D65329

llvm-svn: 367298
2019-07-30 08:20:05 +00:00
Jordan Rupprecht 6a253d378b [lldb] Qualify includes of Properties[Enum].inc files. NFC
Summary:
This is a bit more explicit, and makes it possible to build LLDB without
varying the -I lines per-directory.
(The latter is useful because many build systems only allow this to be
configured per-library, and LLDB is insufficiently layered to be split into
multiple libraries on stricter build systems).

(My comment on D65185 has some more context)

Reviewers: JDevlieghere, labath, chandlerc, jdoerfert

Reviewed By: labath

Subscribers: mgorny, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D65397

Patch by Sam McCall!

llvm-svn: 367241
2019-07-29 17:22:10 +00:00
Jonas Devlieghere a8ea595509 [lldb] Also include the array definition in Properties.inc
Right now our Properties.inc only generates the initializer for the
options list but not the array declaration boilerplate around it. As the
array definition is identical for all arrays, we might as well also let
the Properties.inc generate it alongside the initializers.

Unfortunately we cannot do the same for enums, as there's this magic
ePropertyExperimental, which needs to come at the end to be interpreted
correctly. Hopefully we can get rid of this in the future and do the
same for the property enums.

Differential revision: https://reviews.llvm.org/D65353

llvm-svn: 367238
2019-07-29 16:41:30 +00:00
Pavel Labath d67b550df5 DWARF: Improve type safety or range lists parsing
Delete the abstract GetOffset function, which is only defined for
rnglists entries. Instead fix up entries which refer to the range list
classes so that one can statically know that he is dealing with the
rnglists section and call the function that way.

llvm-svn: 367106
2019-07-26 13:15:28 +00:00
Jonas Devlieghere 971f9ca612 Let tablegen generate property definitions
Property definitions are currently defined in a PropertyDefinition array
and have a corresponding enum to index in this array. Unfortunately this
is quite error prone. Indeed, just today we found an incorrect merge
where a discrepancy between the order of the enum values and their
definition caused the test suite to fail spectacularly.

Tablegen can streamline the process of generating the property
definition table while at the same time guaranteeing that the enums stay
in sync. That's exactly what this patch does. It adds a new tablegen
file for the properties, building on top of the infrastructure that
Raphael added recently for the command options. It also introduces two
new tablegen backends: one for the property definitions and one for
their corresponding enums.

It might be worth mentioning that I generated most of the tablegen
definitions from the existing property definitions, by adding a dump
method to the struct. This seems both more efficient and less error
prone that copying everything over by hand. Only Enum properties needed
manual fixup for the EnumValues and DefaultEnumValue fields.

Differential revision: https://reviews.llvm.org/D65185

llvm-svn: 367058
2019-07-25 21:36:37 +00:00
Pavel Labath f46e8974de SymbolVendor: Remove the type list member
Summary:
Similarly to the compile unit lists, the list of types can also be
managed by the symbol file itself.

Since the only purpose of this list seems to be to maintain an owning
reference to all the types a symbol file has created (items are only
ever added to the list, never retrieved), I remove the passthrough
functions in SymbolVendor and Module. I also tighten the interface of
the function (return a reference instead of a pointer, make it protected
instead of public).

Reviewers: clayborg, JDevlieghere, jingham

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D65135

llvm-svn: 366994
2019-07-25 08:22:05 +00:00
Pavel Labath e0119909a6 SymbolVendor: Move compile unit handling into the SymbolFile class
Summary:
SymbolFile classes are responsible for creating CompileUnit instances
and they already need to have a notion of the id<->CompileUnit mapping
(because of APIs like ParseCompileUnitAtIndex). However, the
SymbolVendor has remained as the thing responsible for caching created
units (which the SymbolFiles were calling via convoluted constructs like
"m_obj_file->GetModule()->GetSymbolVendor()->SetCompileUnitAtIndex(...)").

This patch moves the responsibility of caching the units into the
SymbolFile class. It does this by moving the implementation of
SymbolVendor::{GetNumCompileUnits,GetCompileUnitAtIndex} into the
equivalent SymbolFile functions. The SymbolVendor functions become just
a passthrough much like the rest of SymbolVendor.

The original implementations of SymbolFile::GetNumCompileUnits is moved
to "CalculateNumCompileUnits", and are made protected, as the "Get"
function is the external api of the class.
SymbolFile::ParseCompileUnitAtIndex is made protected for the same
reason.

This is the first step in removing the SymbolVendor indirection, as
proposed in
<http://lists.llvm.org/pipermail/lldb-dev/2019-June/015071.html>. After
removing all interesting logic from the SymbolVendor class, I'll proceed
with removing the indirection itself.

Reviewers: clayborg, jingham, JDevlieghere

Subscribers: jdoerfert, lldb-commits

Differential Revision: https://reviews.llvm.org/D65089

llvm-svn: 366791
2019-07-23 09:24:02 +00:00
Jonas Devlieghere f893d5bf0f [FileSpecList] Add EmplaceBack method (NFC)
Instead of having to write FileSpecList::Append(FileSpec(args)) you can
now call FileSpecList::EmplaceBack(args), similar to
std::vector<>::emplace_back.

llvm-svn: 366489
2019-07-18 20:19:24 +00:00
Pavel Labath 3b9269882e DWARF: Add "dwo_num" field to the DIERef class
Summary:
When dwo support was introduced, it used a trick where debug info
entries were referenced by the offset of the compile unit in the main
file, but the die offset was relative to the dwo file. Although there
was some elegance to it, this representation was starting to reach its
breaking point:
- the fact that the skeleton compile unit owned the DWO file meant that
  it was impossible (or at least hard and unintuitive) to support DWO
  files containing more than one compile unit. These kinds of files are
  produced by LTO for example.
- it made it impossible to reference any DIEs in the skeleton compile
  unit (although the skeleton units are generally empty, clang still
  puts some info into them with -fsplit-dwarf-inlining).
- (current motivation) it made it very hard to support type units placed
  in DWO files, as type units don't have any skeleton units which could
  be referenced in the main file

This patch addresses this problem by introducing an new
"dwo_num" field to the DIERef class, whose purpose is to identify the
dwo file. It's kind of similar to the dwo_id field in DWARF5 unit
headers, but while this is a 64bit hash whose main purpose is to catch
file mismatches, this is just a smaller integer used to indentify a
loaded dwo file. Currently, this is based on the index of the skeleton
compile unit which owns the dwo file, but it is intended to be
eventually independent of that (to support the LTO use case).

Simultaneously the cu_offset is dropped to conserve space, as it is no
longer necessary.  This means we can remove the "BaseObjectOffset" field
from the DWARFUnit class. It also means we can remove some of the
workarounds put in place to support the skeleton-unit+dwo-die combo.
More work is needed to remove all of them, which is out of scope of this
patch.

Reviewers: JDevlieghere, clayborg, aprantl

Subscribers: mehdi_amini, dexonsmith, arphaman, lldb-commits

Differential Revision: https://reviews.llvm.org/D63428

llvm-svn: 364009
2019-06-21 07:56:50 +00:00
Pavel Labath 67b45acefe DWARF: Make DIERefs always valid
Summary:
This patch makes the DIERef class always valid by default constructor
and operator bool. This allows one to express the validity of a DIERef
in the type system. Places which are working with potentially-invalid
DIERefs have been updated to use Optional<DIERef> instead.

The constructor taking a DWARFFormValue was not needed, as all places
which were constructing a DIERef this way were immediately converting it
into a DWARFDIE or a user_id. This can be done without constructing an
intermediate DIERef.

Reviewers: JDevlieghere, clayborg, aprantl

Subscribers: arphaman, lldb-commits

Differential Revision: https://reviews.llvm.org/D63399

llvm-svn: 363767
2019-06-19 07:32:39 +00:00
Pavel Labath a71ce4f1e8 DWARF: Avoid storing DIERefs in long-lived containers
Summary:
A user_id_t carries the same information as a DIERef, but it takes up
less space.

Furthermore, DIERef::operator<'s implementation is very
questionable, as it does not take the cu_offset and section fields into
account. Using just the die offset was correct in the days when all
debug info lived in a single section, but since we started supporting
DWO debug info, this was no longer true. The comparison operator could
be fixed, but it seems like using the user_id_t for these purposes is a
better idea overall.

I think this did not cause any bugs, because the only place the
comparison operator was used is in m_function_scope_qualified_name_map,
and this one is local to a dwo file, but I am not 100% sure of that.

Reviewers: clayborg, JDevlieghere

Subscribers: aprantl, lldb-commits

Differential Revision: https://reviews.llvm.org/D63322

llvm-svn: 363528
2019-06-17 07:32:56 +00:00
Pavel Labath 00e3968b8a DWARF: port debug_ranges/rnglists over to DWARFContext
llvm-svn: 363400
2019-06-14 14:12:25 +00:00
Pavel Labath 6a2eb36710 Have DWARFUnit store a *reference* to SymbolFileDWARF
Previously it was storing a *pointer*, which left open the possibility
of this pointer being null. We never made use of that possibility (it
does not make sense), and most of the code was already assuming that.
However, there were a couple of null-checks scattered around the code.

This patch replaces the reference with a pointer, making the
non-null-ness explicit, and removes the remaining null-checks.

llvm-svn: 363381
2019-06-14 13:01:16 +00:00
Pavel Labath 78b2cf71f5 DWARFIndex: s/ReportInvalidDIEOffset/ReportInvalidDIERef
In a dwo/debug_types world, the die offset is not enough to uniquely
idendify a debug info entry. Pass the the entire DIERef object instead.

This is technically NFC, because only AppleIndex implemented this
method (and there, the die offset *is* enough for unique
identification). However, this makes the code simpler, and simplifies
some of the follow-up patches.

llvm-svn: 363373
2019-06-14 12:01:18 +00:00
Pavel Labath ad17e289f0 DWARF: Don't create lldb CompileUnits for DWARF type units
Summary:
Type units don't represent actual compilations and a lot of the
operations that we do with lldb compile units (getting their line
tables, variables, etc.) don't make sense for them. There is also a lot
more of them (sometimes over 100x), so making them more lightweight pays
off.

The main change in this patch is that we stop creating lldb CompileUnits
for DWARF type units. The trickiest part here is that the SymbolFile
interface requires that we assign consecutive sequence IDs to the
compile units we create. As DWARF type and compile units can come in any
order (in v5), this means we can no longer use 1-1 mapping between DWARF
and lldb compile units. Instead I build a translation table between the
two indices. To avoid pessimizing the case where there are no type
units, I build the translation table only in case we have at least one
type unit.

Additionaly, I also tried to strenghted type safete by replacing
DWARFUnit with DWARFCompileUnit where applicable. Though that was not
stricly necessary, I found it a good way to ensure that the
transformations I am doing here make sense. In the places where I was
changing the function signatures, and where it was obvious that the
objects being handled were not null, I also replaced pointers with
references.

There shouldn't be any major functional change with this patch. The only
change I observed is that now the types in the type units will not be
parsed when one calls Module::ParseAllDebugSymbols, unless they are
referenced from other compile units. This makes sense, given how
ParseAllDebugSymbols is implemented (it iterates over all compile
units), and it only matters for one hand-writted test where I did not
bother to reference the types from the compile units (which I now do).

Reviewers: clayborg, JDevlieghere, aprantl

Subscribers: jdoerfert, lldb-commits

Differential Revision: https://reviews.llvm.org/D63005

llvm-svn: 363250
2019-06-13 11:22:47 +00:00
Pavel Labath ca9c3de17e DWARF: Share line tables of type units
Summary:
This patch creates a cache of file lists in line tables referenced by
type units.  This cache is used to avoid parsing a line table twice
(since a file list will generally be shared by many type units).

It also sets things up in a way that parsing of DW_AT_decl_file
attributes will keep working even when we stop creating lldb compile
units for dwarf type units, but it stops short of actually doing that.
This means that the request for files now go directly to SymbolFileDWARF
instead of being routed there indirectly via the
lldb_private::CompileUnit class.

As a result of this, a number of occurences of SymbolContext variables
in DWARFASTParserClang have become unused, so I remove them.

This patch reduces the number of times a file list is being parsed, but
the situation is still suboptimal, as the parsed list is being copied
multiple times. This will be fixed when we stop creating CompileUnits
for DWARF type units.

Reviewers: clayborg, aprantl, JDevlieghere

Subscribers: jdoerfert, lldb-commits

Differential Revision: https://reviews.llvm.org/D62894

llvm-svn: 363143
2019-06-12 11:29:50 +00:00
Alex Langford 5ada887bf2 Revert "DWARF: Simplify SymbolFileDWARF::GetDWARFCompileUnit"
This reverts commit 58afc1bdebf9fa8b178d6c9d89af94c5cc091760.
This commit caused the test suite on macOS to fail many tests. It
appears that setting breakpoints is the issue. One example that fails
is the lit test Breakpoint/case-sensitive.test.

llvm-svn: 362862
2019-06-08 00:55:03 +00:00
Pavel Labath 62c905a2e6 DWARF: Simplify SymbolFileDWARF::GetDWARFCompileUnit
Summary:
The DWARFCompileUnit is set as the "user data" of the lldb compile unit
directly in the constructor (see ParseCompileUnit).

This means that instead of going through unit indexes, we can just fetch
the DWARF unit directly from there.

Reviewers: clayborg, JDevlieghere

Subscribers: aprantl, jdoerfert, lldb-commits

Differential Revision: https://reviews.llvm.org/D62943

llvm-svn: 362783
2019-06-07 09:43:47 +00:00
Pavel Labath 377c1cfe94 Revert "D11003: Tolerate DWARF compile unit without filename."
Summary:
This code is modifying a support file list after it has been created.
This makes it hard to share the file list between type units and
compile units in DWARF. It's not a total showstopper, but supporting
this while also sharing the lists would make things more complicated.

Given that this was added to support a project which never fully
materialised, and that even back then there were some concerns about the
correctness of this approach (according to D11003#200772 the compile
unit name is not guaranteed to be the first one in the support file
list), I think we should just delete this workaround.

Reviewers: clayborg, tberghammer, dsrbecky

Subscribers: aprantl, lldb-commits

Differential Revision: https://reviews.llvm.org/D62517

llvm-svn: 361948
2019-05-29 11:28:35 +00:00
Pavel Labath 78cfe1e6fe DWARF: Fix address range support in mixed 4+5 scenario
Summary:
debug_ranges got renamed to debug_rnglists in DWARF 5. Prior to this
patch lldb was just picking the first section it could find in the file,
and using that for all address ranges lookups. This is not correct in
case the file contains a mixture of compile units with various standard
versions (not a completely unlikely scenario).

In this patch I make lldb support reading from both sections
simulaneously, and decide the correct section to use based on the
version number of the compile unit. SymbolFileDWARF::DebugRanges is
split into GetDebugRanges and GetDebugRngLists (the first one is renamed
mainly so we can catch all incorrect usages).

I tried to structure the code similarly to how llvm handles this logic
(hence DWARFUnit::FindRnglistFromOffset/Index), but the implementations
are still relatively far from each other.

Reviewers: JDevlieghere, aprantl, clayborg

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D62302

llvm-svn: 361938
2019-05-29 09:22:36 +00:00
Jonas Devlieghere d02da8f42c [SymbolFileDWARF] Remove unused member (NFC)
Removes the unused debug line instance.

llvm-svn: 361886
2019-05-28 22:33:30 +00:00
Jonas Devlieghere 04a087ace7 [DWARFExpression] Remove ctor that takes just a compile unit.
Like many of our DWARF classes, the DWARFExpression can be initialized
in several ways. One such way was through a constructor that takes just
the compile unit. This constructor is used to initialize both empty
DWARFExpressions, and DWARFExpression that will be populated later.

To make the distinction more clear, I changed the constructor to a
default constructor and updated its call sites. Where the
DWARFExpression was being populated later, I replaced that with a call
to the copy assignment constructor.

Differential revision: https://reviews.llvm.org/D62425

llvm-svn: 361849
2019-05-28 17:34:05 +00:00
Pavel Labath 519ef6afdf DWARF: Remove cu_idx variables from parsing functions
These variables were useful when looking up the compile unit index
required a binary search. Now that we can look up a compile unit index
in constant time, they are no longer needed.

llvm-svn: 361754
2019-05-27 10:10:59 +00:00
Greg Clayton 6aad81cd96 Cleanup fixed form sizes.
The fix form sizes use to have two arrays: one for 4 byte addresses and in for 8 byte addresses. The table had an issue where DW_FORM_flag_present wasn't being represented as a fixed size form because its actual size _is_ zero and zero was used to indicate the form isn't fixed in size. Any code that needed to quickly access the DWARF had to get a FixedFormSizes instance using the address byte size.

This fix cleans things up by adding a DWARFFormValue::GetFixedSize() both as a static method and as a member function on DWARFFormValue. It correctly can indicate if a form size is zero. This cleanup is a precursor to a follow up patch where I hope to speed up DWARF parsing.

I verified performance doesn't regress by loading hundreds of DWARF files and setting a breakpoint by file and line and by name in files that do not have DWARF indexes. Performance remained consistent between the two approaches.


Differential Revision: https://reviews.llvm.org/D62416

llvm-svn: 361675
2019-05-24 22:08:50 +00:00
Jonas Devlieghere 09ad8c8f73 Fix integer literals which are cast to bool
This change replaces built-in types that are implicitly converted to
booleans.

Differential revision: https://reviews.llvm.org/D62284

llvm-svn: 361580
2019-05-24 00:44:33 +00:00
Konrad Kleine 248a13057a [lldb] NFC modernize codebase with modernize-use-nullptr
Summary:
NFC = [[ https://llvm.org/docs/Lexicon.html#nfc | Non functional change ]]

This commit is the result of modernizing the LLDB codebase by using
`nullptr` instread of `0` or `NULL`. See
https://clang.llvm.org/extra/clang-tidy/checks/modernize-use-nullptr.html
for more information.

This is the command I ran and I to fix and format the code base:

```
run-clang-tidy.py \
	-header-filter='.*' \
	-checks='-*,modernize-use-nullptr' \
	-fix ~/dev/llvm-project/lldb/.* \
	-format \
	-style LLVM \
	-p ~/llvm-builds/debug-ninja-gcc
```

NOTE: There were also changes to `llvm/utils/unittest` but I did not
include them because I felt that maybe this library shall be updated in
isolation somehow.

NOTE: I know this is a rather large commit but it is a nobrainer in most
parts.

Reviewers: martong, espindola, shafik, #lldb, JDevlieghere

Reviewed By: JDevlieghere

Subscribers: arsenm, jvesely, nhaehnle, hiraditya, JDevlieghere, teemperor, rnkovacs, emaste, kubamracek, nemanjai, ki.stfu, javed.absar, arichardson, kbarton, jrtc27, MaskRay, atanasyan, dexonsmith, arphaman, jfb, jsji, jdoerfert, lldb-commits, llvm-commits

Tags: #lldb, #llvm

Differential Revision: https://reviews.llvm.org/D61847

llvm-svn: 361484
2019-05-23 11:14:47 +00:00
Pavel Labath 80233daeaa DWARF: Introduce DWARFTypeUnit class
Summary:
This patch introduces the DWARFTypeUnit class, and teaches lldb to parse
type units out of both the debug_types section (DWARF v4), and from the
regular debug_info section (DWARF v5).

The most important piece of functionality - resolving DW_AT_signatures
to connect type forward declarations to their definitions - is not
implemented here, but even without that, a lot of functionality becomes
available. I've added tests for the commands that start to work after
this patch.

The changes in this patch were greatly inspired by D61505, which in turn took
over changes from D32167.

Reviewers: JDevlieghere, clayborg, aprantl

Subscribers: mgorny, jankratochvil, lldb-commits

Differential Revision: https://reviews.llvm.org/D62008

llvm-svn: 361360
2019-05-22 09:09:39 +00:00
Jan Kratochvil b7a1932144 Remove `SymbolFileDWARF *` when there is already `DWARFUnit *`
In D61502#1503247 @clayborg suggested that SymbolFileDWARF *dwarf2Data is
really redundant in all the calls with also having DWARFUnit *cu. So remove it.

One `SymbolFileDWARF *` nullptr check
(DWARFDebugInfoEntry::GetDIENamesAndRanges) could be removed, other two nullptr
checks (DWARFDebugInfoEntry::GetName and DWARFDebugInfoEntry::AppendTypeName)
need to stay in place (now for `DWARFUnit *`).

Differential Revision: https://reviews.llvm.org/D62011

llvm-svn: 361277
2019-05-21 17:38:56 +00:00
Pavel Labath f33f181678 DWARF: Port debug_addr over to DWARFContext
llvm-svn: 361232
2019-05-21 09:11:11 +00:00
Pavel Labath 0261b9498b DWARF: Port most of other sections over to DWARFContext
This moves the sections from SymbolFileDWARF to DWARFContext, where it
was trivial to do so. A couple of sections are still left in
SymbolFileDWARF. These will be handled by separate patches.

llvm-svn: 361127
2019-05-20 08:38:47 +00:00
Pavel Labath ff9b4263f9 Make DWARFContext dwo-aware and port debug_info sections over
Summary:
The previous attempt and moving section handling over to DWARFContext
(D59611) failed because it did not take into account the dwo sections
correctly. All DWARFContexts (even those in SymbolFileDWARFDwo) used the
main module for loading the sections, but in the dwo scenario some
sections should come from the dwo file.

This patch fixes that by making the DWARFContext aware of whether it a
dwo context or a regular one. A dwo context gets two sections lists, and
it knows where to look for a particular type of a section. This isn't
fully consistent with how the llvm DWARFContext behaves, because that
one leaves it up to the user to know whether it should ask for a dwo
section or not. However, for the time being, it seems useful to have a
single entity which knows how to peice together the debug info in dwo
and non-dwo scenarios. The rough roadmap for the future is:
- port over the rest of the sections to DWARFContext
- find a way to get rid of SymbolFileDWARFDwo/Dwp/DwpDwo. This will
  likely involve adding the ability for the DWARFContext to spawn
  dwo sub-contexts, similarly to how it's done in llvm.
- get rid of the special handling of the "dwo" contexts by making
  sure everything knows whether it should ask for the .dwo version of
  the section or not (similarly to how llvm's DWARFUnits do that)

To demonstrate how the DWARFContext should behave in this new world, I
port the debug_info section (which is debug_info.dwo in the dwo file)
handling to DWARFContext. The rest of the sections will come in
subsequent patches.

Reviewers: aprantl, clayborg, JDevlieghere

Subscribers: zturner, lldb-commits

Differential Revision: https://reviews.llvm.org/D62012

llvm-svn: 361000
2019-05-17 08:26:58 +00:00
Pavel Labath f4014e116e DWARF: Add ability to reference debug info coming from multiple sections
Summary:
This patch adds the ability to precisely address debug info in
situations when a single file can have more than one debug-info-bearing
sections (as is the case with type units in DWARF v4).

The changes here can be classified into roughly three categories:
- the code which addresses a debug info by offset gets an additional
  argument, which specifies the section one should look into.
- the DIERef class also gets an additional member variable specifying
  the section. This way, code dealing with DIERefs can know which
  section is the object referring to.
- the user_id_t encoding steals one bit from the dwarf_id field to store
  the section. This means the total number of separate object files
  (apple .o, or normal .dwo) is limited to 2 billion, but that is fine
  as it's not possible to hit that number without switching to DWARF64
  anyway.

This patch is functionally equivalent to (and inspired by) the two
patches (D61503 and D61504) by Jan Kratochvil, but there are differences
in the implementation:
- it uses an enum instead of a bool flag to differentiate the sections
- it increases the size of DIERef struct instead of reducing the amount
  of addressable debug info
- it sets up DWARFDebugInfo to store the units in a single vector
  instead of two. This sets us up for the future in which type units can
  also live in the debug_info section, and I believe it's cleaner
  because there's no need for unit index remapping

There are no tests with this patch as this is essentially NFC until
we start parsing type units from the debug_types section.

Reviewers: JDevlieghere, clayborg, aprantl

Subscribers: arphaman, jankratochvil, lldb-commits

Differential Revision: https://reviews.llvm.org/D61908

llvm-svn: 360872
2019-05-16 11:07:58 +00:00
Jan Kratochvil e8a039d62c Permit cross-CU references
So far dw_offset_t was global for the whole SymbolFileDWARF but with
.debug_types the same dw_offset_t may mean two different things depending on
its section (=CU). So references now return whole new referenced DWARFDIE
instead of just dw_offset_t.

This means that some functions have to now handle 16 bytes instead of 8 bytes
but I do not see that anywhere performance critical.

Differential Revision: https://reviews.llvm.org/D61502

llvm-svn: 360795
2019-05-15 19:22:33 +00:00
Pavel Labath 381ba9aedc [DWARF] Use sequential integers for the IDs of the SymbolFileDWOs
Summary:
Instead of using the offset of the contained compile unit, we use it's
ID. The goal of this change is two-fold:
- free up space in the user_id_t representation to enable storing the
  debug-info-carrying section (debug_types/debug_info) without
  decreasing the amount of debug info we can address (as would be the
  case with D61503).
- be a step towards supporting DWO files containing more than one unit
  (important for debug_types+dwo, but can also happen with regular
  dwo+lto). For this part to fully work we'd still need to add a way to
  lookup the SymbolFileDWO without going through GetCompileUnitAtIndex,
  but making sure things don't accidentally work because the SymbolFile
  ID is the same as compile unit offset is a step towards that.

Reviewers: JDevlieghere, clayborg, aprantl

Subscribers: mehdi_amini, dexonsmith, tberghammer, jankratochvil, lldb-commits

Differential Revision: https://reviews.llvm.org/D61783

llvm-svn: 360565
2019-05-13 08:58:34 +00:00
Jan Kratochvil 605627374e Finish renaming CompileUnit -> Unit
D42892 changed a lot of code to use superclass DWARFUnit instead of its
subclass DWARFCompileUnit.

Finish this change more thoroughly for any *CompileUnit* -> *Unit* names.
Later patch will introduce DWARFTypeUnit which needs to be sometimes different
from DWARFCompileUnit and it would be confusing without this renaming.

Differential Revision: https://reviews.llvm.org/D61501

llvm-svn: 360443
2019-05-10 17:14:37 +00:00
Pavel Labath 2841e6edc8 [DWARF] Centralize user_id <-> DWARFDIE conversions
Summary:
The logic for translating a user_id into a DWARFDIE was replicated in
several places. This removes that redundancy and settles on a single
implementation in SymbolFileDWARF.

The reason for choosing that instead of DIERef was that we were
always immediately converting the returned DIERef into a DWARFDIE
anyway, which meant that one had to specify the SymbolFileDWARF argument
twice (once to get the DIERef, and once to get the actual DIE). Also,
passing a higher-level object (SymbolFileDWARF) into a lower-level one
(DIERef) seemed like a less intuitive arrangement than doing things the
other way around.

Reviewers: JDevlieghere, clayborg, aprantl

Subscribers: tberghammer, jankratochvil, lldb-commits

Differential Revision: https://reviews.llvm.org/D61648

llvm-svn: 360246
2019-05-08 11:43:05 +00:00