Commit Graph

1523 Commits

Author SHA1 Message Date
Alex Langford 22b044877d [lldb][NFCI] Remove unused LanguageType parameters
These parameters are unused in these methods, and some of them only had a
LanguageType parameter to pipe to other methods that don't use it
either.
2020-01-30 21:57:23 -08:00
James Henderson 7116e431c0 [DebugInfo] Make most debug line prologue errors non-fatal to parsing
Many of the debug line prologue errors are not inherently fatal. In most
cases, we can make reasonable assumptions and carry on. This patch does
exactly that. In the case of length problems, the approach of "assume
stated length is correct" is taken which means the offset might need
adjusting.

This is a relanding of b94191fe, fixing an LLD test and the LLDB build.

Reviewed by: dblaikie, labath

Differential Revision: https://reviews.llvm.org/D72158
2020-01-29 10:23:41 +00:00
Benjamin Kramer adcd026838 Make llvm::StringRef to std::string conversions explicit.
This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.

This is mostly mechanical from a custom clang-tidy check, with a lot of
manual fixups. It uncovers a lot of minor inefficiencies.

This doesn't actually modify StringRef yet, I'll do that in a follow-up.
2020-01-28 23:25:25 +01:00
Pavel Labath c4267b7b13 Revert "[lldb/PDB] Use the new line table constructor"
This reverts commit bb73210ba9 due to
failures on the windows bot.
2020-01-28 17:15:44 +01:00
Pavel Labath bb73210ba9 [lldb/PDB] Use the new line table constructor
The old method of adding line sequences one by one can easily go
quadratic if the sequences are not perfectly sorted. The equivalent
change in DWARF brought a considerable improvement in line table
parsing. It is not clear if the same will be the case for PDB, but this
does bring us a step closer towards removing the dangerous API.
2020-01-28 15:09:14 +01:00
Pavel Labath d8de349951 Revert "[lldb/DWARF] Only match mangled name in full-name function lookup (with accelerators)"
This reverts commit 1b12766883 because of
breaking the mac test suite.

I'm not certain this is the cause because of a concurrent build breakage
which masked this problem, but the failure messages are related to
symbol lookup, which makes this very likely.
2020-01-28 13:46:43 +01:00
Jaroslav Sevcik 1b12766883 [lldb/DWARF] Only match mangled name in full-name function lookup (with accelerators)
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

Reviewed By: labath

Subscribers: aprantl, arphaman, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D73191
2020-01-28 12:16:02 +01:00
shafik 118efa5cda [LLDB][NFC] Adding clarifying comment in SymbolFileDWARFDebugMap::DumpClangAST(...)
It is not obvious that the code was correct since it would seem as if we want to perform the dump for
each symbol file.
2020-01-24 14:01:15 -08:00
Pavel Labath d4b092b341 [lldb/DWARF] Remove a workaround from DebugNamesDWARFIndex
This was needed when asking a compile unit for its dwo component
triggered a infinite recursion if the dwo unit has not been already
parsed.

This has since been fixed.
2020-01-24 12:09:20 +01:00
Raphael Isemann 808142876c [lldb][NFC] Fix all formatting errors in .cpp file headers
Summary:
A *.cpp file header in LLDB (and in LLDB) should like this:
```
//===-- TestUtilities.cpp -------------------------------------------------===//
```
However in LLDB most of our source files have arbitrary changes to this format and
these changes are spreading through LLDB as folks usually just use the existing
source files as templates for their new files (most notably the unnecessary
editor language indicator `-*- C++ -*-` is spreading and in every review
someone is pointing out that this is wrong, resulting in people pointing out that this
is done in the same way in other files).

This patch removes most of these inconsistencies including the editor language indicators,
all the different missing/additional '-' characters, files that center the file name, missing
trailing `===//` (mostly caused by clang-format breaking the line).

Reviewers: aprantl, espindola, jfb, shafik, JDevlieghere

Reviewed By: JDevlieghere

Subscribers: dexonsmith, wuzish, emaste, sdardis, nemanjai, kbarton, MaskRay, atanasyan, arphaman, jfb, abidh, jsji, JDevlieghere, usaxena95, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D73258
2020-01-24 08:52:55 +01:00
shafik fcaf5f6c01 [LLDB] Fix the handling of unnamed bit-fields when parsing DWARF
We ran into an assert when debugging clang and performing an expression on a class derived from DeclContext. The assert was indicating we were getting the offsets wrong for RecordDeclBitfields. We were getting both the size and offset of unnamed bit-field members wrong. We could fix this case with a quick change but as I extended the test suite to include more combinations we kept finding more cases that were being handled incorrectly. A fix that handled all the new cases as well as the cases already covered required a refactor of the existing technique.

Differential Revision: https://reviews.llvm.org/D72953
2020-01-23 14:46:24 -08:00
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
Adrian Prantl fa001767f0 Fix typos 2020-01-21 15:32:34 -08:00
Pavel Labath 5e70f4bdc1 [lldb/breakpad] Use new line table constructor
The old construction method can be quadratic for some inputs. This
approach guarantees a reasonable performance.
2020-01-21 15:04:27 +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
Pavel Labath b7af1bfa6e [lldb/DWARF] Simplify DWARFDebugInfoEntry::LookupAddress
Summary:
This method was doing a lot more than it's only caller needed
(DWARFDIE::LookupDeepestBlock) needed, so I inline it into the caller,
and remove any code which is not actually used. This includes code for
searching for the deepest function, and the code for working around
incomplete DW_AT_low_pc/high_pc attributes on a compile unit DIE (modern
compiler get this right, and this method is called on function DIEs
anyway).

This also improves our llvm consistency, as llvm::DWARFDebugInfoEntry is
just a very simple struct with no nontrivial logic.

Reviewers: JDevlieghere, aprantl

Subscribers: lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D72920
2020-01-20 12:39:59 +01:00
Pavel Labath 06e73f071a [lldb/DWARF] Change how we construct a llvm::DWARFContext
Summary:
The goal of this patch is two-fold. First, it fixes a use-after-free in
the construction of the llvm DWARFContext. This happened because the
construction code was throwing away the lldb DataExtractors it got while
reading the sections (unlike their llvm counterparts, these are also
responsible for memory ownership). In most cases this did not matter,
because the sections are just slices of the mmapped file data. But this
isn't the case for compressed elf sections, in which case the section is
decompressed into a heap buffer. A similar thing also happen with object
files which are loaded from process memory.

The second goal is to make it explicit which sections go into the llvm
DWARFContext -- any access to the sections through both DWARF parsers
carries a risk of parsing things twice, so it's better if this is a
conscious decision. Also, this avoids loading completely irrelevant
sections (e.g. .text). At present, the only section that needs to be
present in the llvm DWARFContext is the debug_line_str. Using it through
both APIs is not a problem, as there is no parsing involved.

The first goal is achieved by loading the sections through the existing
lldb DWARFContext APIs, which already do the caching. The second by
explicitly enumerating the sections we wish to load.

Reviewers: JDevlieghere, aprantl

Subscribers: lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D72917
2020-01-20 11:45:53 +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
Levon Ter-Grigoryan a705cf1acb Expression eval lookup speedup by not returning methods in ManualDWARFIndex::GetFunctions
Summary:
This change is connected with
https://reviews.llvm.org/D69843

In large codebases, we sometimes see Module::FindFunctions (when called from
ClangExpressionDeclMap::FindExternalVisibleDecls) returning huge amounts of
functions.

In current fix I trying to return only function_fullnames from ManualDWARFIndex::GetFunctions when eFunctionNameTypeFull is passed as argument.

Reviewers: labath, jarin, aprantl

Reviewed By: labath

Subscribers: shafik, clayborg, teemperor, arphaman, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D70846
2020-01-14 14:59:56 +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
Pavel Labath 9bb01efa49 [lldb/DWARF] Add is_dwo member to DWARFUnit
Summary:
A skeleton unit can easily be detected by checking the m_dwo_symbol_file
member, but we cannot tell a split unit from a normal unit from the
"inside", which is sometimes useful.

This patch adds a m_is_dwo member to enable this, and align the code
with llvm::DWARFUnit. Right now it's only used to avoid creating a split
unit inside another split unit (which removes one override from
SymbolFileDWARFDwo and brings us a step closer to deleting it), but my
main motivation is fixing the handling of location lists in mixed v4&v5
files. This comes in a separate patch.

Reviewers: JDevlieghere, aprantl, clayborg

Subscribers: dblaikie, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D71750
2020-01-09 13:19:29 +01:00
Alex Langford a63af91528 [lldb] Remove various dead Compare functions 2020-01-08 18:05:33 -08:00
Adrian Prantl 28b9cdd260 Delete dead code.
https://reviews.llvm.org/D58856
2020-01-08 14:32:11 -08:00
Raphael Isemann a95f4c8784 [lldb][NFC] Remove unused variable in DWARFASTParserClang::ParseSingleMember 2020-01-02 11:57:00 +01:00
Raphael Isemann fe8e25a48a [lldb][NFC] Create type-safe function for creating a CompilerType from a QualType
LLDB frequently converts QualType to CompilerType. This is currently done like this:
    result = CompilerType(this, qual_type_var.getAsOpaquePtr())
There are a few shortcomings in this current approach:
  1. CompilerType's constructor takes a void* pointer so it isn't type safe.
  2. We can't add any sanity checks to the CompilerType constructor (e.g. that the type
     actually belongs to the passed ClangASTContext) without expanding the TypeSystem API.
  3. The logic for converting QualType->CompilerType is spread out over all of LLDB so
     changing it is difficult (e.g., what if we want to just pass the type ptr and not the
     1type_ptr | qual_flags1 to CompilerType).

This patch adds a `ClangASTContext::GetType` function similar to the other GetTypeForDecl
functions that does this conversion in a type safe way.

It also adds a sanity check for Tag-based types that the type actually belongs to the
current ClangASTContext (Types don't seem to know their ASTContext, so we have to
workaround by looking at the decl for the underlying TagDecl. This doesn't cover all types
we construct but it's better than no sanity check).
2020-01-02 11:54:45 +01:00
Raphael Isemann b1fb07ddba [lldb][NFC] Simplify ClangASTContext::GetTypeForDecl
Also removes the GetASTContext call from this code.
2019-12-30 00:22:23 +01:00
Raphael Isemann b036f557ce [lldb] Remove some calls to GetASTContext
GetASTContext is really expensive to call as it makes use of the global
mapping from ASTContext to ClangASTContext. This replaces all calls where
we already have the ClangASTContext around and don't need to call
GetASTContext again.
2019-12-26 10:36:36 +01:00
Raphael Isemann caf460d979 [lldb][NFC] Use StringRef in ClangASTContext::GetBuiltinTypeForDWARFEncodingAndBitSize 2019-12-25 19:02:40 +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 46f02fc922 [lldb/DWARF] Fix hostname-stripping logic
This bit of code is trying to strip everything up to the first colon
from all debug info paths, as dwarf2 recommends this syntax for storing
the compilation host name. However, this code was too eager, and it
ended up stripping the entire compilation directory, if it did not
contain a forward slash (or a "x:\").

Normally this does not matter, as all absolute paths will contain one of
these patterns, but this does not have to be the case in case the debug
info is produced by "clang -fdebug-compilation-dir", which can end up
producing a relative compilation directory with no slashes (this is one
of the techniques for producing "relocatable" debug info).
2019-12-23 14:54:22 +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
Raphael Isemann 42ec584a8b [lldb][NFC] Make CompilerDeclContext construction type safe
The CompilerDeclContext constructor takes a void* pointer which
means that all callers of this constructor need to first explicitly
convert all pointers to clang::DeclContext*. This causes that we
for example can't just pass a TranslationUnitDecl* to the constructor without
first casting it to its parent class (as it inherits from both
Decl and DeclContext so the void* pointer is actually a Decl*).

This patch introduces a utility function in the ClangASTContext
which gets rid of the requirement to cast all pointers to
clang::DeclContext. Also moves all constructor calls to use this
function instead which is NFC (beside the change in
DWARFASTParserClangTests.cpp).
2019-12-23 09:56:54 +01:00
Raphael Isemann f9f49d3594 [lldb][NFC] Return a reference from ClangASTContext::getASTContext and remove dead nullptr checks
ClangASTContext::getASTContext() currently returns a ptr but we have an assert there since a
while that the ASTContext is not a nullptr. This causes that we still have a lot of code
that is doing nullptr checks on the result of getASTContext() which is all unreachable code.

This patch changes the return value to a reference to make it clear this can't be a nullptr
and deletes all the nullptr checks.
2019-12-21 22:51:35 +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
Raphael Isemann 268f37df6e [lldb][NFC] Use StringRef in CreateRecordType and CreateObjCClass 2019-12-17 16:10:34 +01:00
Raphael Isemann b852b3c982 [lldb][NFC] Rename ClangASTImporter::InsertRecordDecl to SetRecordLayout and document it
This function is just setting the layout for the given RecordDecl so
the current name is not very descriptive. Also add some documentation for it.
2019-12-17 15:56:07 +01:00
Raphael Isemann d9ca412a8a [lldb][NFC] Remove all unnecessary includes for ClangASTSourceCommon.h
These files only need the definition of ClangASTMetadata (which was
previously in the ClangASTSourceCommon.h) or don't need the include at all.
2019-12-17 11:21:11 +01:00
Raphael Isemann d5b54bbfaf [lldb] Add support for calling objc_direct methods from LLDB's expression evaluator.
Summary:
D69991 introduced `__attribute__((objc_direct))` that allows directly calling methods without message passing.
This patch adds support for calling methods with this attribute to LLDB's expression evaluator.

The patch can be summarised in that LLDB just adds the same attribute to our module AST when we find a
method with `__attribute__((objc_direct))` in our debug information.

Reviewers: aprantl, shafik

Reviewed By: shafik

Subscribers: JDevlieghere, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D71196
2019-12-17 10:28:40 +01:00
Raphael Isemann 5ab9fa44cd [lldb][NFC] Make metadata tracking type safe
Summary:
LLDB associates additional information with Types and Declarations which it calls ClangASTMetadata.
ClangASTMetadata is stored by the ClangASTSourceCommon which is implemented by having a large map of
`void *` keys to associated `ClangASTMetadata` values. To make this whole mechanism even unsafer
we also decided to use `clang::Decl *` as one of pointers we throw in there (beside `clang::Type *`).

The Decl class hierarchy uses multiple inheritance which means that not all pointers have the
same address when they are implicitly converted to pointers of their parent classes. For example
`clang::Decl *` and `clang::DeclContext *` won't end up being the same address when they
are implicitly converted from one of the many Decl-subclasses that inherit from both.

As we use the addresses as the keys in our Metadata map, this means that any implicit type
conversions to parent classes (or anything else that changes the addresses) will break our metadata tracking
in obscure ways.

Just to illustrate how broken this whole mechanism currently is:
```lang=cpp
  // m_ast is our ClangASTContext. Let's double check that from GetTranslationUnitDecl
  // in ClangASTContext and ASTContext return the same thing (one method just calls the other).
  assert(m_ast->GetTranslationUnitDecl() == m_ast->getASTContext()->getTranslationUnitDecl());
  // Ok, both methods have the same TU*. Let's store metadata with the result of one method call.
  m_ast->SetMetadataAsUserID(m_ast->GetTranslationUnitDecl(), 1234U);
  // Retrieve the same Metadata for the TU by using the TU* from the other method... which fails?
  EXPECT_EQ(m_ast->GetMetadata(m_ast->getASTContext()->getTranslationUnitDecl())->GetUserID(), 1234U);
  // Turns out that getTranslationUnitDecl one time returns a TranslationUnitDecl* but the other time
  // we return one of the parent classes of TranslationUnitDecl (DeclContext).
```

This patch splits up the `void *` API into two where one does the `clang::Type *` tracking and one the `clang::Decl *` mapping.
Type and Decl are disjoint class hierarchies so there is no implicit conversion possible that could influence
the address values.

I had to change the storing of `clang::QualType` opaque pointers to their `clang::Type *` equivalents as
opaque pointers are already `void *` pointers to begin with. We don't seem to ever set any qualifier in any of these
QualTypes to this conversion should be NFC.

Reviewers: labath, shafik, aprantl

Reviewed By: labath

Subscribers: JDevlieghere, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D71409
2019-12-13 12:04:42 +01:00
Pavel Labath 6ce1a897b6 [lldb/DWARF] Fix v5 location lists for dwo files
Dwo files don't have a DW_AT_loclists_base -- set one explicitly. Also,
make sure we use the correct location list flavour for v5.
2019-12-12 15:28:11 +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
Raphael Isemann d0fb7a478d [lldb] Support for DWARF-5 atomic types
Summary:
This patch adds support for atomic types (DW_TAG_atomic_type) to LLDB. It's mostly just filling out all the switch-statements that didn't implement Atomic case with the usual boilerplate.

Thanks Pavel for writing the test case.

Reviewers: labath, aprantl, shafik

Reviewed By: labath

Subscribers: jfb, abidh, JDevlieghere, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D71183
2019-12-09 10:46:26 +01:00
Pavel Labath f69f92344a [lldb/DWARF] Fix DW_AT_addr_base & DW_AT_low_pc interaction
In DWARF5 DW_AT_low_pc (and DW_AT_entry_pc, and possibly others) can use
DW_FORM_addrx to refer to the address indirectly. This means we need to
have processed the DW_AT_addr_base attribute before we can do anything
with these.

Since we were processing the unit attributes serially, this created a
problem in cases where the DW_AT_addr_base comes after DW_AT_low_pc --
we would end up computing the wrong unit base address, which also
corrupted any values which later depended on that (for instance range
lists). Clang currently always emits DW_AT_addr_base last.

The fix is simple -- process DW_AT_addr_base first, regardless of its
position in the attribute list.
2019-12-06 10:33:13 +01:00
Pavel Labath 5ee8e67313 [lldb/DWARF] Fix DW_AT_rnglists_base handling for dwo files
the value of DW_AT_rnglists_base of the skeleton unit is for that unit
alone (e.g. used in DW_AT_ranges of the unit DIE) and should not apply
to the split unit.

The split unit has a hardcoded range list base value -- we should
initialize range list code whenever we detect a nonempty
debug_rnglists.dwo section.
2019-12-06 10:26:52 +01:00
Pavel Labath 6e1f3170e0 [lldb/DWARF] Remove DWARFDebugRangesBase abstract class
now that we use llvm to parse debug_rnglists, this abstraction is not
useful.
2019-12-06 10:15:46 +01:00
Raphael Isemann 1462f5a4c1 [lldb][NFC] Move Address and AddressRange functions out of Stream and let them take raw_ostream
Summary:
Yet another step on the long road towards getting rid of lldb's Stream class.

We probably should just make this some kind of member of Address/AddressRange, but it seems quite often we just push
in random integers in there and this is just about getting rid of Stream and not improving arbitrary APIs.

I had to rename another `DumpAddress` function in FormatEntity that is dumping the content of an address to make Clang happy.

Reviewers: labath

Reviewed By: labath

Subscribers: JDevlieghere, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D71052
2019-12-05 14:41:33 +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
Raphael Isemann 4d37f18b29 [lldb][NFC] Extract single member parsing out of DWARFASTParserClang::ParseChildMembers
ParseChildMembers does a few things, only one part is actually parsing a single
member. This extracts the member parsing logic into its own function.

This commit just moves the code as-is into its own function and forwards the parameters/
local variables to it, which means it should be NFC.

The only actual changes to the code are replacing 'break's (and one very curious 'continue'
that behaves like a 'break') with 'return's.
2019-12-04 10:05:40 +01:00
Raphael Isemann d62026e2dd [lldb][NFC] Don't calculate member indices in DWARFASTParserClang::ParseChildMembers
We keep counting members and then don't do anything with the computed result.
2019-12-02 14:43:40 +01:00
Raphael Isemann d1d6049e9d [lldb][NFC] Remove dead logging code from DWARFASTParserClang::CompleteRecordType
This code is behind a `if (log)` that is always a nullptr as the initializer
was commented out. One could uncomment the initializer code, but then this logging
code just leads to a deadlock as it tries to aquire the module lock.
This removes the logging code until I get this working again.
2019-11-29 12:13:34 +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
Raphael Isemann 2e3c040ee0 [lldb][NFC] Remove unused CStringToDIEMap typedef 2019-11-28 13:33:19 +01:00
Raphael Isemann f7e31e0cfd [lldb][NFC] Split up DWARFASTParserClang::CompleteTypeFromDWARF
Moving the different parts into their own functions without any additional
cleanup/refactoring, so this is NFC.
2019-11-28 10:45:29 +01:00
Raphael Isemann b44e91a472 [lldb] Remove debugging code used for LLDB_DWARF_DONT_COMPLETE_TYPENAMES
Reviewers: labath, clayborg, shafik

Reviewed By: labath

Subscribers: JDevlieghere, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D70802
2019-11-28 10:21:58 +01:00
Raphael Isemann 3a280422b6 [lldb][NFC] Early exit in DWARFASTParserClang::ParseArrayType 2019-11-27 09:28:01 +01:00
Raphael Isemann 16144d2b21 [lldb][NFC] Modernize string handling in DWARFASTParserClang::ParseTypeModifier 2019-11-26 15:04:54 +01:00
Raphael Isemann cdfecb82ee [lldb][NFC] Remove no longer unused variable in DWARFASTParserClang::ParseTypeFromDWARF 2019-11-26 14:17:06 +01:00
Raphael Isemann 0181338dda [lldb][NFC] Simplify structure parsing code in DWARFASTParserClang::ParseTypeFromDWARF
This way it looks more like the code around it. The assert is also gone as it just
checks that the variables we declare directly above were not initialized by anyone.
That made more sense when this was one large function.
2019-11-26 14:01:12 +01:00
Pavel Labath 4023bd05fc [lldb] Add boilerplate to recognize the .debug_rnglists.dwo section 2019-11-26 13:58:26 +01:00
Raphael Isemann 30fc94be23 [lldb][NFC] Extract type modifier parsing from DWARFASTParserClang::ParseTypeFromDWARF
Part of the work to split up this monolithic parsing function.
2019-11-26 13:53:06 +01:00
Raphael Isemann 8f2b57d257 [lldb][NFC] Extract enum parsing from DWARFASTParserClang::ParseTypeFromDWARF
Part of the work to split up this monolithic parsing function.
2019-11-26 12:30:06 +01:00
Raphael Isemann 94939650b6 [lldb][NFCI] Extract subroutine parsing from DWARFASTParserClang::ParseTypeFromDWARF
Part of the work to split up this monolithic parsing function.

Should be NFC but due to the kafkaesque control flow in this case statement this might
have some unintended side effects.
2019-11-26 12:14:40 +01:00
Raphael Isemann e8013ef53a [lldb][NFC] Extract array type parsing from DWARFASTParserClang::ParseTypeFromDWARF
Part of the work to split up this monolithic parsing function.
2019-11-26 11:46:25 +01:00
Raphael Isemann 7047a3a729 [lldb][NFC] Extract pointer to member type parsing from DWARFASTParserClang::ParseTypeFromDWARF
Part of the work to split up this monolithic parsing function.
2019-11-26 11:07:59 +01:00
Raphael Isemann cfd9d39567 [lldb][NFC] NULL -> nullptr in DWARFASTParserClang::UpdateSymbolContextScopeForType 2019-11-26 10:35:30 +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 539117616d Complete complete types early when importing types from Clang module DWARF.
This affects -gmodules only.

Under normal operation pcm_type is a shallow forward declaration
that gets completed later. This is necessary to support cyclic
data structures. If, however, pcm_type is already complete (for
example, because it was loaded for a different target before),
the definition needs to be imported right away, too.
Type::ResolveClangType() effectively ignores the ResolveState
inside type_sp and only looks at IsDefined(), so it never calls
ClangASTImporter::ASTImporterDelegate::ImportDefinitionTo(),
which does extra work for Objective-C classes. This would result
in only the forward declaration to be visible.

An alternative implementation would be to sink this into Type::ResolveClangType ( 88235812a7/lldb/source/Symbol/Type.cpp (L5809)) though it isn't clear to me how to best do this from a layering perspective.

rdar://problem/52134074

Differential Revision: https://reviews.llvm.org/D70415
2019-11-22 09:58:16 -08:00
Raphael Isemann 82800df4de [lldb][NFC] Remove ClangASTContext::GetAsDeclContext
Everything we pass to this function is already a DeclContext.
2019-11-20 12:28:16 +01:00
Adrian Prantl d4f18f11d3 Replace bitfield in lldb::Type with byte-sized members. (NFC)
Due to alginment and packing using separate members takes up the same
amount of space, but makes it far less cumbersome to deal with it in
constructors etc.
2019-11-18 10:00:26 -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 3bc71193bd Comment the fact that DWARFDebugInfoEntry isn't copyable. 2019-11-15 09:14:48 -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 83f5287567 Rename DWO -> Clang module to avoid confusion. (NFC) 2019-11-14 09:13:49 -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 9072f0103b Remove redundant check. (NFC) 2019-11-13 14:19:01 -08:00
Adrian Prantl 7f9d36e2db Use cheaper, equivalent predicate. (NFC) 2019-11-13 14:16:40 -08:00
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
Adrian Prantl 78586775f7 Rename ParseTypeFromDWO to ParseTypeFromClangModule (NFC)
Because that is what this function really does. The old name is
misleading.
2019-11-13 13:37:43 -08:00
Jonas Devlieghere ad882774fe [LLDB] Fix a bunch of -Wdocumentation warnings 2019-11-13 12:28:10 -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
Jan Kratochvil 44f43461c0 [lldb] Comment typo fix 2019-11-07 17:48:25 +01:00
shafik de2c7cab71 Add support for DW_AT_export_symbols for anonymous structs
Summary:
We add support for DW_AT_export_symbols to detect anonymous struct on top of the heuristics implemented in D66175
This should allow us to differentiate anonymous structs and unnamed structs.
We also fix TestTypeList.py which was incorrectly detecting an unnamed struct as an anonymous struct.

Differential Revision: https://reviews.llvm.org/D68961
2019-10-28 14:26:54 -07:00
Raphael Isemann b31c624156 [lldb][NFC] Fix typo in DWARFASTParserClang.cpp
llvm-svn: 375187
2019-10-17 23:11:32 +00:00
Sterling Augustine bbbc873f83 (NFC) Delete variable made unused by llvm-svn: 375160
Reviewers: aprantl

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69143

llvm-svn: 375174
2019-10-17 21:40:12 +00:00
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
Raphael Isemann 6237c9fe6c [lldb] Don't emit artificial constructor declarations as global functions
Summary:
When we have a artificial constructor DIE, we currently create from that a global function with the name of that class.
That ends up causing a bunch of funny errors such as "must use 'struct' tag to refer to type 'Foo' in this scope" when
doing `Foo f`. Also causes that constructing a class via `Foo()` actually just calls that global function.

The fix is that when we have an artificial method decl, we always treat it as handled even if we don't create a CXXMethodDecl
for it (which we never do for artificial methods at the moment).

Fixes rdar://55757491 and probably some other radars.

Reviewers: aprantl, vsk, shafik

Reviewed By: aprantl

Subscribers: jingham, shafik, labath, JDevlieghere, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D68130

llvm-svn: 375151
2019-10-17 18:16:50 +00:00
Alex Langford 03fbde6d84 [NativePDB] Remove unused references to ClangASTImporter
llvm-svn: 374587
2019-10-11 20:12:29 +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
Adrian Prantl 418893d8f2 Speed up accelerator table lookups
When debugging a large program like clang and doing "frame variable
*this", the ValueObject pretty printer is doing hundreds of scoped
FindTypes lookups. The ones that take longest are the ones where the
DWARFDeclContext ends in something like ::Iterator which produces many
false positives that need to be filtered out *after* extracting the
DIEs. This patch demonstrates a way to filter out false positives at
the accerator table lookup step.

With this patch
  lldb clang-10 -o "b EmitFunctionStart" -o r -o "f 2" -o "fr v *this" -b -- ...
goes (in user time) from 5.6s -> 4.8s
or (in wall clock) from 6.9s -> 6.0s.

Differential Revision: https://reviews.llvm.org/D68678

llvm-svn: 374401
2019-10-10 17:59:15 +00:00
Adrian Prantl 939411c1aa Remove the is_mangled flag from Mangled and Symbol
Testing whether a name is mangled or not is extremely cheap and can be
done by looking at the first two characters. Mangled knows how to do
it. On the flip side, many call sites that currently pass in an
is_mangled determination do not know how to correctly do it (for
example, they leave out Swift mangling prefixes).

This patch removes this entry point and just forced Mangled to
determine the mangledness of a string itself.

Differential Revision: https://reviews.llvm.org/D68674

llvm-svn: 374180
2019-10-09 16:22:14 +00:00
Adrian Prantl 35b63a435c Revert Trust the arange accelerator tables in dSYMs
This reverts r374117 (git commit 6399db2f6f)
while inspecting bot breakage.

llvm-svn: 374121
2019-10-08 21:34:22 +00:00
Adrian Prantl 6399db2f6f Trust the arange accelerator tables in dSYMs
When ingesting aranges from a dSYM it makes sense to always trust the
contents of the accelerator table since it always comes from
dsymutil. According to Instruments, skipping the decoding of all CU
DIEs to get at the DW_AT_ranges attribute removes ~3.5 seconds from
setting a breakpoint by file/line when debugging clang with a
dSYM. Interestingly on the wall clock the speedup is less noticeable,
but still present.

rdar://problem/56057688

Differential Revision: https://reviews.llvm.org/D68655

llvm-svn: 374117
2019-10-08 21:14:36 +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
Vedant Kumar fccfe2c04a [DWARFASTParserClang] Delete commented-out typedef, NFC
(& group together all the protected members & typedefs)

llvm-svn: 373926
2019-10-07 17:22:50 +00:00
Michal Gorny 9735739be7 [lldb] [cmake] Support linking against clang-cpp dylib
Link against clang-cpp dylib rather than split libs when
CLANG_LINK_CLANG_DYLIB is enabled.

Differential Revision: https://reviews.llvm.org/D68456

llvm-svn: 373734
2019-10-04 12:03:03 +00:00
Raphael Isemann 5c375ed669 [lldb] Fix evaluation of nested classes with parent from other CU
This makes sure that we associate DIEs that are imported from other CUs with the appropriate decl context.

Without this fix, nested classes can be dumped directly into their CU context if their parent was imported from another CU.

Reviewed By: teemperor, labath

Differential Revision: https://reviews.llvm.org/D68278

Patch by Jaroslav Sevcik!

llvm-svn: 373470
2019-10-02 13:46:17 +00:00
Jordan Rupprecht a77c3ef03c [lldb] Fix unused variable warning
llvm-svn: 373399
2019-10-01 22:04:14 +00:00
Adrian Prantl ad08a5f0f1 Fix a condition-flip regression introduced in r373344.
llvm-svn: 373354
2019-10-01 17:08:44 +00:00
Adrian Prantl c7f19caaea Typo (NFC)
llvm-svn: 373353
2019-10-01 17:08:41 +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 796cd312ac Update SymbolFilePDB for FindTypes API change.
This is untested, I don't have access to a Windows machine.

llvm-svn: 373342
2019-10-01 15:29:33 +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
Pavel Labath a8b284eeec Unwind: Add a stack scanning mechanism to support win32 unwinding
Summary:
Windows unwinding is weird. The unwind rules do not (always) describe
the precise layout of the stack, but rather expect the debugger to scan
the stack for something which looks like a plausible return address, and
the unwind based on that. The reason this works somewhat reliably is
because the the unwinder also has access to the frame sizes of the
functions on the stack. This allows it (in most cases) to skip function
pointers in local variables or function arguments, which could otherwise
be mistaken for return addresses.

Implementing this kind of unwind mechanism in lldb was a bit challenging
because we expect to be able to statically describe (in the UnwindPlan)
structure, the layout of the stack for any given instruction. Giving a
precise desription of this is not possible, because it requires
correlating information from two functions -- the pushed arguments to a
function are considered a part of the callers stack frame, and their
size needs to be considered when unwinding the caller, but they are only
present in the unwind entry of the callee. The callee may end up being
in a completely different module, or it may not even be possible to
determine it statically (indirect calls).

This patch implements this functionality by introducing a couple of new
APIs:
SymbolFile::GetParameterStackSize - return the amount of stack space
  taken up by parameters of this function.
SymbolFile::GetOwnFrameSize - the size of this function's frame. This
  excludes the parameters, but includes stuff like local variables and
  spilled registers.

These functions are then used by the unwinder to compute the estimated
location of the return address. This address is not always exact,
because the stack may contain some additional values -- for instance, if
we're getting ready to call a function then the stack will also contain
partially set up arguments, but we will not know their size because we
haven't called the function yet. For this reason the unwinder will crawl
up the stack from the return address position, and look for something
that looks like a possible return address. Currently, we assume that
something is a valid return address if it ends up pointing to an
executable section.

All of this logic kicks in when the UnwindPlan sets the value of CFA as
"isHeuristicallyDetected", which is also the final new API here. Right
now, only SymbolFileBreakpad implements these APIs, but in the future
SymbolFilePDB will use them too.

Differential Revision: https://reviews.llvm.org/D66638

llvm-svn: 373072
2019-09-27 12:10:06 +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
Jonas Devlieghere 7fa72881d4 [Dwarf] Make dw_tag_t a typedef for llvm::dwarf::Tag instead of uint16_t.
Currently dw_tag_t is a typedef for uint16_t. This patch changes makes
dw_tag_t a typedef for llvm::dwarf::Tag. This enables us to use the full
power of the DWARF utilities in LLVM without having to do the cast every
time. With this approach, we only have to do the cast when reading the
ULEB value.

Differential revision: https://reviews.llvm.org/D68005

llvm-svn: 372891
2019-09-25 16:04:38 +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 c3bea40bf7 Breakpad: Basic support for STACK WIN unwinding
Summary:
This patch makes it possible to unwind via breakpad STACK WIN records.
It is "basic" because two important features are missing:
- support for the .raSearch keyword
- support for multiple STACK WIN records within a single function
Right now, we just reject the .raSearch records, and always pick the
first record for the whole function
SymbolFileBreakpad, and so I think it can serve as a good example of
what is needed of the symbol file and unwinding machinery to make this
work.

However, it is already useful for unwinding in some situations, and it
sets up the general framework for the parsing of these kinds of records,
which reduces the size of the followup patches implementing the two
other components.

Reviewers: amccarth, rnk, markmentovai

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D67067

llvm-svn: 371017
2019-09-05 07:05:15 +00:00
Pavel Labath f07b4aff06 Fix GetDIEForDeclContext so it only returns entries matching the provided context
Currently, we return all the entries such that their decl_ctx pointer >= decl_ctx provided.
Instead, we should return only the ones that decl_ctx pointer == decl_ctx provided.

Differential Revision: https://reviews.llvm.org/D66357
Patch by Guilherme Andrade <guiandrade@google.com>.

llvm-svn: 370374
2019-08-29 15:30:52 +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
Pavel Labath c7deb7f808 Postfix: move more code out of the PDB plugin
Summary:
Previously we moved the code which parses a single expression out of the PDB
plugin, because that was useful for DWARF expressions in breakpad. However, FPO
programs are used in breakpad files too (when unwinding on windows), so this
completes the job, and moves the rest of the FPO parser too.

Reviewers: amccarth, aleksandr.urakov

Subscribers: aprantl, markmentovai, rnk, lldb-commits

Differential Revision: https://reviews.llvm.org/D66634

llvm-svn: 369894
2019-08-26 11:44:14 +00:00
Jonas Devlieghere 0a8a225f8e [NFC] Fix comments and formatting.
llvm-svn: 369827
2019-08-23 23:56:19 +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 9a0f124f26 Remove redundant curly braces.
llvm-svn: 369670
2019-08-22 16:58:56 +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 3af3f1e8e2 [Utility] Reimplement RegularExpression on top of llvm::Regex
Originally I wanted to remove the RegularExpression class in Utility and
replace it with llvm::Regex. However, during that transition I noticed
that there are several places where need the regular expression string.
So instead I propose to keep the RegularExpression class and make it a
thin wrapper around llvm::Regex.

This patch also removes the workaround for empty regular expressions.
The result is that we are now (more or less) POSIX conformant.

Differential revision: https://reviews.llvm.org/D66174

llvm-svn: 369153
2019-08-16 21:25:36 +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
Alex Langford bddab07d4a [Symbol] Decouple clang from CompilerType
Summary:
Ideally CompilerType would have no knowledge of clang or any individual
TypeSystem. Decoupling clang is relatively straightforward.

Differential Revision: https://reviews.llvm.org/D66102

llvm-svn: 368741
2019-08-13 19:40:36 +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 579d6d1aa5 Remove Module::GetSymbolVendor
Summary:
This patch removes the GetSymbolVendor function, and the various
mentions of the SymbolVendor in the Module class. The implementation of
GetSymbolVendor is "inlined" into the GetSymbolFile class which I
created earlier.

After this patch, the SymbolVendor class still exists inside the Module
object, but only as an implementation detail -- a fancy holder for the
SymbolFile. That will be removed in the next patch.

Reviewers: clayborg, JDevlieghere, jingham, jdoerfert

Subscribers: jfb, lldb-commits

Differential Revision: https://reviews.llvm.org/D65864

llvm-svn: 368263
2019-08-08 07:34:07 +00:00
Nico Weber 8883ec7da2 Add support for deterministically linked binaries on macOS to lldb.
When ld64 links a binary deterministically using the flag ZERO_AR_DATE,
it sets a timestamp of 0 for N_OSO members in the symtab section, rather
than the usual last modified date of the object file. Prior to this
patch, lldb would compare the timestamp from the N_OSO member against
the last modified date of the object file, and skip loading the object
file if there was a mismatch. This patch updates the logic to ignore the
timestamp check if the N_OSO member has timestamp 0.

The original logic was added in https://reviews.llvm.org/rL181631 as a
safety check to avoid problems when debugging if the object file was out
of date. This was prior to the introduction of deterministic build in
ld64. lld still doesn't support deterministic build.

Other code in llvm already relies on and uses the assumption that a
timestamp of 0 means deterministic build. For example, commit
9ccfddc39d adds similar timestamp checking
logic to dsymutil, but special cases timestamp 0. Likewise, commit
0d1bb79a04 adds a long comment describing
deterministic archive, which mostly uses timestamp 0 for determinism.

Patch from Erik Chen <erikchen@chromium.org>!

Differential Revision: https://reviews.llvm.org/D65826

llvm-svn: 368199
2019-08-07 19:29:04 +00:00
Alex Langford 5fdf10bae8 [SymbolFile] Remove commented out method
llvm-svn: 368075
2019-08-06 19:47:08 +00:00
Igor Kudrin 0be738895c Update LLDB to follow changes in llvm::DWARFDebugNames::NameIndex (4/5)
Differential Revision: https://reviews.llvm.org/D65640

llvm-svn: 368033
2019-08-06 13:38:27 +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
Nilanjana Basu da60fc813c Changing representation of .cv_def_range directives in Codeview debug info assembly format for better readability
llvm-svn: 367867
2019-08-05 14:16:58 +00:00
Nilanjana Basu b5e4d7de17 Revert "Changing representation of .cv_def_range directives in Codeview debug info assembly format for better readability"
This reverts commit a885afa9fa.

llvm-svn: 367861
2019-08-05 13:55:21 +00:00
Nilanjana Basu a885afa9fa Changing representation of .cv_def_range directives in Codeview debug info assembly format for better readability
llvm-svn: 367850
2019-08-05 13:11:51 +00:00
Shafik Yaghmour fa5c340ea1 Fix ClangASTContext::CreateParameterDeclaration to not call addDecl
Summary:
The change https://reviews.llvm.org/D55575 modified ClangASTContext::CreateParameterDeclaration to call decl_ctx->addDecl(decl); this caused a regression since the existing code in DWARFASTParserClang::ParseChildParameters is called with the containing DeclContext. So when end up with cases where we are parsing a parameter for a member function and the parameter is added to the CXXRecordDecl as opposed to the CXXMethodDecl. This example is given in the regression test TestBreakpointInMemberFuncWNonPrimitiveParams.py which without this fix in a modules build leads to assert on setting a breakpoint in a member function with non primitive parameters. This scenario would be common when debugging LLDB or clang.

Differential Revision: https://reviews.llvm.org/D65414

llvm-svn: 367726
2019-08-02 21:41:50 +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
Greg Clayton af44f18ad6 Don't crash when pass by value struct has no definition.
llvm-svn: 367441
2019-07-31 16:24:55 +00:00
Pavel Labath e84f78412b Add llvm-style RTTI to ObjectFile hierarchy
Summary:
On the heels of D62934, this patch uses the same approach to introduce
llvm RTTI support to the ObjectFile hierarchy. It also replaces the
existing uses of GetPluginName doing run-time type checks with
llvm::dyn_cast and friends.

This formally introduces new dependencies from some other plugins to
ObjectFile plugins. However, I believe this is fine because:
- these dependencies were already kind of there, and the only reason
  we could get away with not modeling them explicitly was because the
  code was relying on magically knowing what will GetPluginName() return
  for a particular kind of object files.
- the dependencies themselves are logical (it makes sense for
  SymbolVendorELF to depend on ObjectFileELF), or at least don't
  actively get in the way (the JitLoaderGDB->MachO thing).
- they don't introduce any new dependency loops as ObjectFile plugins
  don't depend on any other plugins

Reviewers: xiaobai, JDevlieghere, espindola

Subscribers: emaste, mgorny, arichardson, MaskRay, lldb-commits

Differential Revision: https://reviews.llvm.org/D65450

llvm-svn: 367413
2019-07-31 11:57:34 +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
Richard Trieu 33cdbff2a7 Change '|' to '&' in conditional.
Bitwise-or with a non-zero constant will always evaluate to true.  Switch to
bitwise-and which will only evalute to true if the specified bit is set in the
other operand.

llvm-svn: 367386
2019-07-31 04:41:05 +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
Jonas Devlieghere 63e5fb76ec [Logging] Replace Log::Printf with LLDB_LOG macro (NFC)
This patch replaces explicit calls to log::Printf with the new LLDB_LOGF
macro. The macro is similar to LLDB_LOG but supports printf-style format
strings, instead of formatv-style format strings.

So instead of writing:

  if (log)
    log->Printf("%s\n", str);

You'd write:

  LLDB_LOG(log, "%s\n", str);

This change was done mechanically with the command below. I replaced the
spurious if-checks with vim, since I know how to do multi-line
replacements with it.

  find . -type f -name '*.cpp' -exec \
  sed -i '' -E 's/log->Printf\(/LLDB_LOGF\(log, /g' "{}" +

Differential revision: https://reviews.llvm.org/D65128

llvm-svn: 366936
2019-07-24 17:56:10 +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
Nathan Lanza fe1b8a0911 [NativePDB] Make GetOrCreateDeclForUid return an lldb CompilerDecl
We intend to make PdbAstBuilder abstract and implement
PdbAstBuilderClang along with any other languages that wish to use
PDBs. Thus, change GetOrCreateDeclForUid from returning a clang decl
to a lldb_private::CompilerDecl.

llvm-svn: 366650
2019-07-21 07:46:18 +00:00
Joseph Tremoulet 3fd917d886 Support Linux signal return trampolines in frame initialization
Summary:
Add __kernel_rt_sigreturn to the list of trap handlers for Linux (it's
used as such on aarch64 at least), and __restore_rt as well (used on
x86_64).

Skip decrement-and-recompute for trap handlers in
InitializeNonZerothFrame, as signal dispatch may point the child frame's
return address to the start of the return trampoline.

Parse the 'S' flag for signal handlers from eh_frame augmentation, and
propagate it to the unwind plan.

Reviewers: labath, jankratochvil, compnerd, jfb, jasonmolenda

Reviewed By: jasonmolenda

Subscribers: clayborg, MaskRay, wuzish, nemanjai, kbarton, jrtc27, atanasyan, jsji, javed.absar, kristof.beyls, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D63667

llvm-svn: 366580
2019-07-19 14:05:55 +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
Nathan Lanza 3b96ebeee4 [NativePDB] Add a FromCompilerDecl for going from lldb -> clang
Summary:
A common transformation in NativePDB is to go from lldb types to clang
types and vice versa. This function automates one of those steps.

Differential Revision: https://reviews.llvm.org/D64851

llvm-svn: 366345
2019-07-17 16:43:36 +00:00
Nathan Lanza 06bf5d8538 [NativePDB] Make GetTranslationUnitDecl return an lldb CompilerDeclCtx
Summary:
We intend to make PdbAstBuilder abstract and implement
PdbAstBuilderClang along with any other languages that wish to use
PDBs. This is the first step.

Differential Revision: https://reviews.llvm.org/D64852

llvm-svn: 366293
2019-07-17 07:05:49 +00:00
Jonas Devlieghere b016de51e0 [DWARFContext] Strip leading dot in section names
The LLVM context doesn't expect the leading dot in the section name.

llvm-svn: 365978
2019-07-13 00:12:22 +00:00
Jonas Devlieghere f4af9a9d80 Add convenience methods to convert LLDB to LLVM data structures.
This patch adds two convenience methods named GetAsLLVM to the LLDB
counterparts of the DWARF DataExtractor and the DWARF context. The
DWARFContext, once created, is cached for future usage.

Differential revision: https://reviews.llvm.org/D64535

llvm-svn: 365819
2019-07-11 20:26:53 +00:00
Alex Langford d7fcee62f1 [Core] Generalize ValueObject::IsRuntimeSupportValue
Summary:
Instead of falling back to ObjCLanguageRuntime, we should be falling
back to every loaded language runtime. This makes ValueObject more
language agnostic.

Reviewers: labath, compnerd, JDevlieghere, davide

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D63240

llvm-svn: 364845
2019-07-01 20:36:33 +00:00
Fangrui Song a83e94ebf2 Use const auto *
llvm-svn: 364702
2019-06-29 00:55:13 +00:00
Pavel Labath fcad3bc415 DWARF: Add support for type units+split dwarf combo
Summary:
With the last round of refactors, supporting type units in dwo files
becomes almost trivial. This patch contains a couple of small fixes,
which taken as a whole make type units work in the split dwarf scenario
(both DWARF4 and DWARF5):
- DWARFContext: make sure we actually read the debug_types.dwo section
- DWARFUnit: set string offsets base on all units in the dwo file, not
  just the main CU
- ManualDWARFIndex: index all units in the file
- SymbolFileDWARFDwo: Search for the single compile unit in the file, as
  we can no longer assume it will be the first one

The last part makes it obvious that there is still some work to be done
here, namely that we do not support dwo files with multiple compile
units. That is something that should be easier after the DIERef
refactors, but it still requires more work.

Tests are added for the type units+split dwarf + dwarf4/5 scenarios, as
well as a test that checks we behave reasonably in the presence of dwo
files with multiple CUs.

Reviewers: clayborg, JDevlieghere, aprantl

Subscribers: arphaman, lldb-commits

Differential Revision: https://reviews.llvm.org/D63643

llvm-svn: 364274
2019-06-25 06:59:48 +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 5418d335e1 Fix -Wmismatched-tags introduced in r363910
That commit changed DIERef from a struct to a class, but did not update
the forward-declarations. This fixes one forward-declaration, and
removes other (unused) decls.

llvm-svn: 363915
2019-06-20 09:46:37 +00:00
Pavel Labath 0de98ebd00 DWARF: Provide accessors to DIERef fields
Summary:
Instead of accessing the fields directly, use accessor functions to
provide access to the DIERef components. This allows us to decouple the
external interface, from the internal representation. The external
interface can use llvm::Optional and similar goodies, while the data can
still be stored internally in a more compact representation.

I also document the purpose of the existing DIERef fields.

The main motivation for this change is a need to introduce an additional
field to the DIERef class, but I believe the change has its own merit.

Reviewers: JDevlieghere, aprantl, clayborg

Subscribers: arphaman, lldb-commits

Differential Revision: https://reviews.llvm.org/D63400

llvm-svn: 363910
2019-06-20 08:24:46 +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
Greg Clayton 6df47ef22b Don't try to parse ObjC method if CU isn't ObjC
Improve manual indexing performance when indexing non objective C code. 

Differential Revision: https://reviews.llvm.org/D63171

llvm-svn: 363441
2019-06-14 19:18:10 +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 fe79fbc99d DWARF: Remove unused includes from DWARFDebugAranges.h/cpp
llvm-svn: 363382
2019-06-14 13:21:57 +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
Jorge Gorbe Moya 13427e64de [lldb] Fix msan use-of-uninitialized-value in DWARFDebugLine::FileNameEntry.
lldb/lit/SymbolFile/DWARF/debug-types-expressions.test fails with msan.
This change fixes the issue by ensuring FileNameEntry::checksum is
always default-initialized.

llvm-svn: 362843
2019-06-07 21:09:30 +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 da7f033693 Ignore DIEs in the skeleton unit in a DWO scenario
Summary:
r362103 exposed a bug, where we could read incorrect data if a skeleton
unit contained more than the single unit DIE. Clang emits these kinds of
units with -fsplit-dwarf-inlining (which is also the default).

Changing lldb to handle these DIEs is nontrivial, as we'd have to change
the UID encoding logic to be able to reference these DIEs, and fix up
various places which are assuming that all DIEs come from the separate
compile unit.

However, it turns out this is not necessary, as the DWO unit contains
all the information that the skeleton unit does. So, this patch just
skips parsing the extra DIEs if we have successfully found the DWO file.
This enforces the invariant that the rest of the code is already
operating under.

This patch fixes a couple of existing tests, but I've also included a
simpler test which does not depend on execution of binaries, and would
have helped us in catching this sooner.

Reviewers: clayborg, JDevlieghere, aprantl

Subscribers: probinson, dblaikie, lldb-commits

Differential Revision: https://reviews.llvm.org/D62852

llvm-svn: 362586
2019-06-05 07:29:55 +00:00
Tom Tan 382320ea02 [COFF, ARM64] Fix CodeView API change for getRegisterNames
Change rL362280 changed CodeView API getRegisterNames() by adding an input
parameter in CPUType. It is called in LLDB and needs to be updated.

Differential Revision: https://reviews.llvm.org/D62772

llvm-svn: 362349
2019-06-03 00:48:16 +00:00
Greg Clayton aeae786bfe Code and comment cleanups [NFC]
Changes:
- update comments to detail the info can come from .debug_info or .debug_types
- Rename "debug_info_data" to "data" now that we can get data from .debug_info or .debug_types.
- Also call DWARFDebugInfoEntry::GetAbbreviationDeclarationPtr(...) instead of manually grabbing abbreviation.

llvm-svn: 362116
2019-05-30 17:03:35 +00:00
Greg Clayton e6ddde57e2 Fix a regression in DWARF access speed caused by svn revision 356190
The issue was caused by the error checking code that was added. It was incorrectly adding an extra abbreviation when DWARFEnumState::Complete was received since it would push an extra abbreviation onto the list with the abbreviation code of zero. This cause m_idx_offset in each DWARFAbbreviationDeclarationSet to be set to UINT32_MAX. This valid indicates we must linearly search for attributes, not access them in O(1) time. This caused every DWARFDebugInfoEntry that would try to get its DWARFAbbreviationDeclaration from the CU's DWARFAbbreviationDeclarationSet to always linearly search the abbreviation set for a given abbreviation code. Easy to see why this would cause things to be slow.

This regression was caused by: https://reviews.llvm.org/D59370. I asked to ensure there was no regression is parsing or access speed, but that must not have been done. In my test with 40 DWARF files trying to set a breakpoint by function name and in a header file, I see a 8% speed improvement with this fix.

There was no regression in correctness, just very inefficient access.

Added full unit testing for DWARFAbbreviationDeclarationSet parsing to ensure this doesn't regress.

Differential Revision: https://reviews.llvm.org/D62630

llvm-svn: 362105
2019-05-30 15:32:33 +00:00
Greg Clayton 202c3ffcbf Improve DWARF parsing and accessing by 1% to 2%
When LLDB first started we didn't have our mmap of the DWARF data done correctly and if the backing file would change we would get live changes as the file changed and it would cause problems. We now mmap correctly and do not run into these issues. There was legacy code in DWARFDebugInfoEntry::GetAbbreviationDeclarationPtr(...) that would always extract the abbrev index each time the function was called to verify that DWARF data hadn't changed and a warning was emitted if it did. We no longer need this and the code was removed. The other thing this function did when it parsed the abbrev index was give us the offset of the first attribute bytes by adding the LEB128 size to the offset. This required an extra parameter to DWARFDebugInfoEntry::GetAbbreviationDeclarationPtr(...) which is now removed. I added "lldb::offset_t DWARFDebugInfoEntry::GetFirstAttributeOffset() const" which calculates this when we need it and modified all sites that need the offset to call it.

Now that we aren't decoding and verifying the abbrev index, it speeds up DWARF access by 1% to 2%.

Differential Revision: https://reviews.llvm.org/D62634

llvm-svn: 362103
2019-05-30 15:21:23 +00:00
Pavel Labath c767011329 DWARFASTParserClang: Delete dead code
This removes places where DW_AT_decl_file/line/column was being parsed,
but not used.

llvm-svn: 362086
2019-05-30 11:24:16 +00:00
Pavel Labath 7e4d62a8dd DWARFASTParserClang: Move attribute parsing into a single function
Summary:
The ParseTypeFromDWARF function consists of a huge switch on the kind of
type being parsed. Each case in this switch starts with parsing the
attributes of the current DIE. A lot of these attributes are specific to
one kind of a type, but a lot of them are common too, leading to code
duplication.

This patch reduces the duplication (and the size of ParseTypeFromDWARF)
by moving the attribute parsing to a separate function. It creates a
struct (ParsedTypeAttributes), which contains a parsed form of all
attributes which are useful for parsing any kind of a type. The parsing
code for a specific type kind can then access the fields which are
relevant for that specific case.

Reviewers: JDevlieghere, clayborg, aprantl

Subscribers: jdoerfert, lldb-commits

Differential Revision: https://reviews.llvm.org/D62477

llvm-svn: 362075
2019-05-30 09:39:36 +00:00
Fangrui Song a05fda68bc DWARFDebugInfoEntry: delete unused Extract() and rename FastExtract() to Extract()
The function Extract() is almost a duplicate of FastExtract() but is not used.
Delete it and rename FastExtract() to Extract().

Reviewed By: JDevlieghere

Differential Revision: https://reviews.llvm.org/D62593

llvm-svn: 362049
2019-05-30 01:51:16 +00:00
Fangrui Song 898aaf1cb8 Clean up DWARFDebugInfoEntry
llvm-svn: 361962
2019-05-29 14:36:11 +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 d2042d3dd7 DWARFASTParserClang: Unify compilation unit language handling
Summary:
The function was not being consistent in how it retrieved the language
of the current compile unit. Sometimes it did so from the lldb CU
object, and sometimes from the DWARF die. This patch unifies the
handling on the latter. The reason for choosing the DWARF method is
because I'd eventually like to stop creating lldb CUs for dwarf type
units (and so this code needs to would need to work without them).

Reviewers: clayborg, JDevlieghere, aprantl

Subscribers: jdoerfert, lldb-commits

Differential Revision: https://reviews.llvm.org/D62481

llvm-svn: 361939
2019-05-29 09:32:59 +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 11e0549145 DWARFDebugArangeSet: Remove references to SymbolFileDWARF
This class does not depend on SymbolFileDWARF. Instead, include more
appropriate low-level headers.

llvm-svn: 361765
2019-05-27 14:16:15 +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
Pavel Labath f750842c8b DWARF: Implement DW_AT_signature lookup for type unit support
Summary:
This patch implements the main feature of type units. When completing a
type, if we encounter a DW_AT_signature attribute, we use it's value to
lookup the complete definition of the type in the relevant type unit.

To enable this lookup, we build up a map of all type units in a symbol
file when parsing the units. Then we consult this map when resolving the
DW_AT_signature attribute.

I include add a couple of tests which exercise the type lookup feature,
including one that ensure we do something reasonable in case we fail to
lookup the type.

A lot of the ideas in this patch have been taken from D32167 and D61505.

Reviewers: clayborg, JDevlieghere, aprantl, alexshap

Subscribers: mgrang, lldb-commits

Differential Revision: https://reviews.llvm.org/D62246

llvm-svn: 361603
2019-05-24 08:11:12 +00:00
Pavel Labath 8ac0bc9832 DWARFContext: Make loading of sections thread-safe
Summary:
SymbolFileDWARF used to load debug sections in a thread-safe manner.
When we moved to DWARFContext, we dropped the thread-safe part, because
we thought it was not necessary.

It turns out this was only mostly correct.

The "mostly" part is there because this is a problem only if we use the
manual index, as that is the only source of intra-module paralelism.
Also, this only seems to occur for extremely simple files (like the ones
I've been creating for tests lately), where we've managed to start
indexing before loading the debug_str section. Then, two threads start
to load the section simultaneously and produce wrong results.

On more complex files, something seems to be loading the debug_str section
before we start indexing, as I haven't been able to reproduce this
there, but I have not investigated what it is.

I've tried to come up with a test for this, but I haven't been able to
reproduce the problem reliably. Still, while doing so, I created a way
to generate many compile units on demand. Given that most of our tests
work with only one or two compile units, it seems like this could be
useful anyway.

Reviewers: aprantl, JDevlieghere, clayborg

Subscribers: arphaman, lldb-commits

Differential Revision: https://reviews.llvm.org/D62316

llvm-svn: 361602
2019-05-24 08:04:03 +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 691502f61e DWARFASTParserClang: Reduce indentation
by two levels via early returns.

llvm-svn: 361471
2019-05-23 09:41:39 +00:00
Pavel Labath 324396466c DWARF: Don't compute address ranges for type units
Summary:
Type units don't describe any code, so they should never be the result
of any address lookup queries.

Previously, we would compute the address ranges for the type units for
via the line tables they reference because the type units looked a lot
like line-tables-only compile units. However, this is not correct, as
the line tables are only referenced from type units so that other
declarations can use the file names contained in them.

In this patch I make the BuildAddressRangeTable function virtual, and
implement it only for compile units.

Testing this was a bit tricky, because the behavior depends on the order
in which we add things to the address range map. This rarely caused a
problem with DWARF v4 type units, as they are always added after all
CUs. It happened more frequently with DWARF v5, as there clang emits the
type units first. However, this is still not something that it is
required to do, so for testing I've created an assembly file where I've
deliberately sandwiched a compile unit between two type units, which
should isolate us from both changes in how the compiler emits the units
and changes in the order we process them.

Reviewers: clayborg, aprantl, JDevlieghere

Subscribers: jdoerfert, lldb-commits

Differential Revision: https://reviews.llvm.org/D62178

llvm-svn: 361465
2019-05-23 09:07:51 +00:00
Jan Kratochvil 19a3c30731 Simplify `GetName`+`AppendTypeName` by `DWARFDIE`
In D61502#1503247 @clayborg suggested that DWARFUnit *+dw_offset_t can be now
replaced by DWARFDIE.

It is moved from DWARFDebugInfoEntry to DWARFDIE as noted by @clayborg.

I have also removed return type as (1) it was wrong in one case and (2) no
existing caller used the return type. I also refactored the deep nesting noted
by @JDevlieghere.

Differential Revision: https://reviews.llvm.org/D62211

llvm-svn: 361463
2019-05-23 08:00:49 +00:00
Pavel Labath 7b0b4b49d3 DWARFDebugInfoEntry: remove unused variable
llvm-svn: 361361
2019-05-22 09:09:44 +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 03c4bf73ea DWARF: Introduce DWARFUnitHeader class
Summary:
This patch introduces the DWARFUnitHeader class. Its purpose (and its
structure, to the extent it was possible to make it) is the same as its
LLVM counterpart -- to extract the unit header information before we
actually construct the unit, so that we know which kind of units to
construct. This is needed because as of DWARF5, type units live in the
.debug_info section, which means it's not possible to statically
determine the type of units in a given section.

Reviewers: aprantl, clayborg, JDevlieghere

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D62073

llvm-svn: 361224
2019-05-21 07:22:34 +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 1a8630ac28 DWARFContext: Return empty data extractors instead of null pointers
Summary:
There are several reasons for doing this:
- generally, there's no reason to differentiate between a section being
  absent and it being present, but empty
- it matches more closely what llvm DWARF parser is doing (which also
  doesn't differentiate the two cases)
- SymbolFileDWARF also doesn't differentiate the two cases, which makes
  porting the rest of sections easier
- it fixes a bug in how the return-null-if-empty logic was implemented
  (it returned nullptr only the second time we tried to get the
  debug_aranges section), which meant that we hit an assert when trying
  to parse an empty-but-present section

Reviewers: JDevlieghere, clayborg, aprantl

Subscribers: zturner, lldb-commits

Differential Revision: https://reviews.llvm.org/D61942

llvm-svn: 360874
2019-05-16 11:19:02 +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 041f40e5da DWARF: s/CompileUnit/Unit/ in DWARFFormValue
The class has been converted to use DWARFUnit, but a number of uses of
the words compile unit remained. This removes all such references
Get/SetCompileUnit becomes Get/SetUnit, and m_cu becomes m_unit.

llvm-svn: 360754
2019-05-15 07:45:40 +00:00
Pavel Labath 62f5b591f4 DWARF/NFC: Centralize DIERef conversions
apple and manual indexing code were creating a DIERef in a bunch of
places. Though the code itself is not much, it is also easy to simplify
by factoring out the DIERef creation. In HashedNameToDIE I create a
conversion operator from DIEInfo to DIERef, and in ManualDWARFIndex I
just create the DIERef in a global variable up-front.

This also reduces the diff in follow-up patches which change how DIERefs
are constructed.

llvm-svn: 360669
2019-05-14 12:44:40 +00:00
Pavel Labath b1e28d9b6a DWARF/DIERef: remove non-const operator<
It serves no purpose as one can always invoke the const version instead.

llvm-svn: 360583
2019-05-13 13:52:40 +00:00
Pavel Labath 1211baa51c Breakpad: Generate unwind plans from STACK CFI records
Summary:
This patch implements the GetUnwindPlan interface (added in the previous
patch) for SymbolFileBreakpad, and uses it to generate unwind plans from
STACK CFI records in breakpad files.

We first perform a light-weight parse of the breakpad in order to build
up a map of regions covered by the unwind info so that we can later jump
to the right record when we need to unwind a specific function.

The actual parsing is relatively straight-forward, as the STACK CFI records
are just another (text) form of the eh_frame unwind instructions, and
the same goes for lldb's UnwindPlans. The newly-introduced
PostfixExpression API is used to convert the breakpad postfix
expressions into DWARF. The generated dwarf expressions are stored in a
BumpPtrAllocator, as the UnwindPlan does not take ownership of the
expression data it references (usually this is static data in an object
file, so special ownership is needed).

At this moment the generated unwind plans aren't used in the actual
unwind machinery (only in the image show-unwind command), but that is
coming in a separate patch.

Reviewers: amccarth, clayborg, markmentovai

Subscribers: aprantl, jasonmolenda, lldb-commits

Differential Revision: https://reviews.llvm.org/D61733

llvm-svn: 360574
2019-05-13 11:25:35 +00:00
Aleksandr Urakov 869f934d19 [NativePDB] Support member function types in PdbAstBuilder
Summary:
    This patch implements missing case in PdbAstBuilder::CreateType for
    LF_MFUNCTION. This is necessary, for example, in stack unwinding of struct
    methods.

    Reviewers: amccarth, aleksandr.urakov

    Reviewed By: amccarth

    Subscribers: abidh, teemperor, lldb-commits, leonid.mashinskiy

    Differential Revision: https://reviews.llvm.org/D61128

llvm-svn: 360569
2019-05-13 09:41:57 +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
Fangrui Song b0e54cbcdf Fix file names in file headers. NFC
llvm-svn: 360554
2019-05-13 04:42:32 +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
Jan Kratochvil 4ce1c3c3ff Merge GetCompileUnitAtOffset + GetCompileUnitContainingDIEOffset
These two methods are very similar and various refactorizations need to modify
both similar ways.

One could also just remove GetCompileUnitAtOffset and make
GetCompileUnitContainingDIEOffset to also accept offset of the CU itself
(currently it accepts only DIE offsets after the CU header).
But that would be less safe regarding some internal sanity checking.

Further code refactorization has been suggested by Pavel Labath.

Differential Revision: https://reviews.llvm.org/D61498

llvm-svn: 360038
2019-05-06 12:01:38 +00:00
Pavel Labath 2a0cfcce6a [DWARF] Reimplement/simplify DWARFUnit::GetID
Summary:
The implementation of GetID used a relatively complicated algorithm,
which returned some kind of an offset of the unit in some file
(depending on the debug info flavour). The only thing this ID was used
for was to enable subseqent retrieval of the unit from the SymbolFile.

This can be made simpler if we just make the "ID" of the unit an index
into the list of the units belonging to the symbol file. We already
support indexed access to the units, so each unit already has a well
"index" -- this just makes it accessible from within the unit.

To make the distincion between "id" and "offset" clearer (and help catch
any misuses), I also rename DWARFDebugInfo::GetCompileUnit (which
accesses by offset) into DWARFDebugInfo::GetCompileUnitAtOffset.

On its own, this only brings a minor simplification, but it enables
further simplifications in the DIERef class (coming in a follow-up
patch).

Reviewers: JDevlieghere, clayborg, aprantl

Subscribers: arphaman, jdoerfert, lldb-commits, tberghammer, jankratochvil

Differential Revision: https://reviews.llvm.org/D61481

llvm-svn: 360014
2019-05-06 07:45:28 +00:00
Raphael Isemann 21db1440f9 Remove unnecessary check in SymbolFileDWARF::ParseImportedModules
Summary:
This check seems unnecessary as we already assert the same condition above and also access `sc.comp_unit`
before this check.

Reviewers: aprantl

Reviewed By: aprantl

Subscribers: jdoerfert, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D61394

llvm-svn: 359813
2019-05-02 18:26:58 +00:00
Shafik Yaghmour 2097b1f84d Set a CXXRecordDecl to not be passed in registers if DW_CC_pass_by_reference when loading from DWARF
Summary:
This will fix a bug where during expression parsing we are not setting a CXXRecordDecl to not be passed in registers and the resulting code generation is wrong.
The DWARF attribute DW_CC_pass_by_reference tells us that we should not be passing in registers i.e. RAA_Indirect.
This change depends this clang change which fixes the fact that the ASTImporter does not copy RecordDeclBits for CXXRecordDecl: https://reviews.llvm.org/D61140

Differential Revision: https://reviews.llvm.org/D61146

llvm-svn: 359732
2019-05-01 22:23:06 +00:00
Raphael Isemann c53f8db770 Removed unnecessary conversion to StringRef
llvm-svn: 359664
2019-05-01 09:49:07 +00:00
Pavel Labath 0eadd98866 PostfixExpression: move DWARF generator out of NativePDB internals
Summary:
The new dwarf generator is pretty much a verbatim copy of the one in
PDB.

In order to write a pdb-independent test for it, I needed to write a
dummy "symbol resolver", which (together with the fact that I'll need
one more for breakpad-specific resolution logic) prompted me to create a
more simple interface for algorithms which replace or "resolve"
SymbolNodes. The resolving algorithms in NativePDB have been updated to
make use of that too.

I have removed a couple of NativePDB tests which weren't testing
anything pdb-specific and where the tested functionality was covered by
the new format-agnostic tests I have added.

Reviewers: amccarth, clayborg, aleksandr.urakov

Subscribers: aprantl, markmentovai, lldb-commits, jasonmolenda, JDevlieghere

Differential Revision: https://reviews.llvm.org/D61056

llvm-svn: 359288
2019-04-26 08:52:04 +00:00
Frederic Riss 265df39a80 Fix infinite recursion when calling C++ template functions
Summary:
When we encounter a templated function in the debug information, we
were creating an AST that looked like this:

FunctionTemplateDecl 0x12980ab90 <<invalid sloc>> <invalid sloc> foo<int>
|-TemplateTypeParmDecl 0x12980aad0 <<invalid sloc>> <invalid sloc> class depth 0 index 0 T
|-FunctionDecl 0x12980aa30 <<invalid sloc>> <invalid sloc> foo<int> 'int (int)' extern
| |-TemplateArgument type 'int'
| `-ParmVarDecl 0x12980a998 <<invalid sloc>> <invalid sloc> t1 'int'
`-FunctionDecl 0x12980aa30 <<invalid sloc>> <invalid sloc> foo<int> 'int (int)' extern
  |-TemplateArgument type 'int'
  `-ParmVarDecl 0x12980a998 <<invalid sloc>> <invalid sloc> t1 'int'

Note that the FunctionTemplateDecl has 2 children which are identical (as
in have the same address). This is not what Clang is doing:

FunctionTemplateDecl 0x7f89d206c6f8 </tmp/template.cpp:1:1, line:4:1> line:2:5 foo
|-TemplateTypeParmDecl 0x7f89d206c4a8 <line:1:10, col:19> col:19 referenced typename depth 0 index 0 T
|-FunctionDecl 0x7f89d206c660 <line:2:1, line:4:1> line:2:5 foo 'int (T)'
| `-ParmVarDecl 0x7f89d206c570 <col:9, col:11> col:11 t1 'T'
`-FunctionDecl 0x7f89d206cb60 <line:2:1, line:4:1> line:2:5 used foo 'int (int)'
  |-TemplateArgument type 'int'
  `-ParmVarDecl 0x7f89d206ca68 <col:9, col:11> col:11 t1 'int':'int'

The 2 chidlren are different and actually repesent different things: the first
one is the unspecialized version and the second one is specialized. (Just looking
at the names shows another major difference which is that we create the parent
with a name of "foo<int>" when it should be just "foo".)

The fact that we have those 2 identical children confuses the ClangImporter
and generates an infinite recursion (reported in https://llvm.org/pr41473).
We cannot create the unspecialized version as the debug information doesn't
contain a mapping from the template parameters to their use in the prototype.

This patch just creates 2 different FunctionDecls for those 2 children of the
FunctionTemplateDecl. This avoids the infinite recursion and allows us to
call functions. As the XFAILs in the added test show, we've still got issues
in our handling of templates. I believe they are mostly centered on the fact
that we create do not register "foo" as a template, but "foo<int>". This is
a bigger change that will need changes to the debug information generation.
I believe this change makes sense on its own.

Reviewers: shafik, clayborg, jingham

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

Differential Revision: https://reviews.llvm.org/D61044

llvm-svn: 359140
2019-04-24 21:04:23 +00:00
Pavel Labath 88813103cd PostfixExpression: move parser out of NativePDB internals
Summary:
The postfix expressions in PDB and breakpad symbol files are similar
enough that they can be parsed by the same parser. This patch
generalizes the parser in the NativePDB plugin and moves it into the
PostfixExpression file created in the previous commit (r358976).

The generalization consists of treating any unrecognised token as a
"symbol" node (previously these would only be created for tokens
starting with "$", and other token would abort the parse). This is
needed because breakpad symbols can also contain ".cfa" tokens, which
refer to the frame's CFA.

The cosmetic changes include:
- using a factory function instead of a class for creating nodes (this
  is more generic as it allows the same BumpPtrAllocator to be used for
  other things too)
- using dedicated function for parsing operator tokens instead of a
  DenseMap (more efficient as we don't need to create the DenseMap every
  time).

Reviewers: amccarth, clayborg, JDevlieghere, aleksandr.urakov

Subscribers: jasonmolenda, lldb-commits, markmentovai, mgorny

Differential Revision: https://reviews.llvm.org/D61003

llvm-svn: 359073
2019-04-24 07:27:05 +00:00
Frederic Riss acbf0058e9 Lock accesses to OptionValueFileSpecList objects
Before a Debugger gets a Target, target settings are routed to a global set
of settings. Even without this, some part of the LLDB which exist independently
of the Debugger object (the Module cache, the Symbol vendors, ...) access
directly the global default store for those settings.

Of course, if you modify one of those global settings while they are being read,
bad things happen. We see this quite a bit with FileSpecList settings. In
particular, we see many cases where one debug session changes
target.exec-search-paths while another session starts up and it crashes when
one of those accesses invalid FileSpecs.

This patch addresses the specific FileSpecList issue by adding locking to
OptionValueFileSpecList and never returning by reference.

Reviewers: clayborg

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D60468

llvm-svn: 359028
2019-04-23 20:17:04 +00:00