Commit Graph

57 Commits

Author SHA1 Message Date
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
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 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
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
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
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 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
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
Jonas Devlieghere 8b3af63b89 [NFC] Remove ASCII lines from comments
A lot of comments in LLDB are surrounded by an ASCII line to delimit the
begging and end of the comment.

Its use is not really consistent across the code base, sometimes the
lines are longer, sometimes they are shorter and sometimes they are
omitted. Furthermore, it looks kind of weird with the 80 column limit,
where the comment actually extends past the line, but not by much.
Furthermore, when /// is used for Doxygen comments, it looks
particularly odd. And when // is used, it incorrectly gives the
impression that it's actually a Doxygen comment.

I assume these lines were added to improve distinguishing between
comments and code. However, given that todays editors and IDEs do a
great job at highlighting comments, I think it's worth to drop this for
the sake of consistency. The alternative is fixing all the
inconsistencies, which would create a lot more churn.

Differential revision: https://reviews.llvm.org/D60508

llvm-svn: 358135
2019-04-10 20:48:55 +00:00
Pavel Labath 4c2ef9a02b Revert "Move the rest of the sections over to DWARFContext."
This reverts commit r356682 because it breaks the DWO flavours of some
tests:
    lldb-Suite :: lang/c/const_variables/TestConstVariables.py
    lldb-Suite :: lang/c/local_variables/TestLocalVariables.py
    lldb-Suite :: lang/c/vla/TestVLA.py

llvm-svn: 356773
2019-03-22 16:07:58 +00:00
Zachary Turner b4fe87d0c9 Move the rest of the sections over to DWARFContext.
This is mostly mechanical, and just moves the remaining non-DWO
related sections over to DWARFContext.

Differential Revision: https://reviews.llvm.org/D59611

llvm-svn: 356682
2019-03-21 16:34:58 +00:00
Zachary Turner 1cbbab9277 Return Error and Expected from more DWARF interfaces.
This continues the work of introducing Error and Expected into
the DWARF parsing interfaces, this time for the DWARFCompileUnit
and DWARFDebugAranges classes.

Differential Revision: https://reviews.llvm.org/D59381

llvm-svn: 356278
2019-03-15 17:32:05 +00:00
Adrian Prantl f05b42e960 Bring Doxygen comment syntax in sync with LLVM coding style.
This changes '@' prefix to '\'.

llvm-svn: 355841
2019-03-11 17:09:29 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
George Rimar c6c7bfc4d2 [LLDB] - Improved DWARF5 support.
This patch improves the support of DWARF5.
Particularly the reporting of source code locations.

Differential revision: https://reviews.llvm.org/D51935

llvm-svn: 342153
2018-09-13 17:06:47 +00:00
Jan Kratochvil cd9c15cda1 Remove friend class declarations from DWARFUnit and DWARFCompileUnit
They are no longer needed since D45170.

llvm-svn: 338224
2018-07-29 19:32:36 +00:00
Greg Clayton f56c30d13b General cleanup to minimize the .debug_types patch
This cleanup is designed to make the https://reviews.llvm.org/D32167 patch smaller and easier to read.

Cleanup in this patch:

Allow DWARFUnit subclasses to hand out the data that should be used when decoding data for a DIE. The information might be in .debug_info or could be in .debug_types. There is a new virtual function on DWARFUnit that each subclass must override:

virtual const lldb_private::DWARFDataExtractor &DWARFUnit::GetData() const;
This allows DWARFCompileUnit and eventually DWARFTypeUnit to hand out different data to be used when decoding the DIE information.

Add a new pure virtual function to get the size of the DWARF unit header:

virtual uint32_t DWARFUnit::GetHeaderByteSize() const = 0;
This allows DWARFCompileUnit and eventually DWARFTypeUnit to hand out different offsets where the first DIE starts when decoding DIE information from the unit.

Added a new function to DWARFDataExtractor to get the size of an offset:

size_t DWARFDataExtractor::GetDWARFSizeOfOffset() const;
Removed dead dumping and parsing code in the DWARFDebugInfo class.
Inlined a bunch of calls in DWARFUnit for accessors that were just returning integer member variables.
Renamed DWARFUnit::Size() to DWARFUnit::GetHeaderByteSize() as it clearly states what it is doing and makes more sense.

Differential Revision: https://reviews.llvm.org/D46606

llvm-svn: 331892
2018-05-09 16:42:53 +00:00
Jan Kratochvil d950892cf0 Reapply "Cleanup DWARFCompileUnit and DWARFUnit in preparation for adding DWARFTypeUnit".
This patch by Greg Clayton drops the virtualization for DWARFPartialUnit.
The virtualization of DWARFUnit now matches more its LLVM counterpart.
DWZ patchset is going to be implementable without DWARFPartialUnit remapping.
	https://reviews.llvm.org/D40474

This reverts commit 329423.
This reapplies commit r329305.

llvm-svn: 330084
2018-04-14 11:12:52 +00:00
Jan Kratochvil 7ea906459a Revert "Cleanup DWARFCompileUnit and DWARFUnit in preparation for adding DWARFTypeUnit"
The reverted commit changed DWARFUnit from https://reviews.llvm.org/D40466 and
https://reviews.llvm.org/D42892 that was prepared for DWARFPartialUnit and
made from it a superclass for DWARFTypeUnit.  DWARFUnit's intention was:
	DWARFUnit->DWARFSomeNameUnit->DWARFCompileUnit
	DWARFUnit->DWARFSomeNameUnit->DWARFTypeUnit
	DWARFUnit->DWARFPartialUnit

Discussed at: https://reviews.llvm.org/D45170

This reverts commit r329305.

llvm-svn: 329423
2018-04-06 17:11:13 +00:00
Greg Clayton 118bcd9ce2 Cleanup DWARFCompileUnit and DWARFUnit in preparation for adding DWARFTypeUnit
Many things that were in DWARFCompileUnit actually need to be in DWARFUnit. This patch moves all DWARFUnit specific things over into DWARFUnit and fixes the layering. This is in preparation for adding DWARFTypeUnit for the .debug_types patch.

Differential Revision: https://reviews.llvm.org/D45170

llvm-svn: 329305
2018-04-05 15:52:39 +00:00
Jan Kratochvil c4d65751df Move the codebase to use: DWARFCompileUnit -> DWARFUnit
Now the codebase can use the DWARFUnit superclass. It will make it later
seamlessly work also with DWARFPartialUnit for DWZ.

This patch is only a search-and-replace easily undone, nothing interesting
in it.

Differential revision: https://reviews.llvm.org/D42892

llvm-svn: 327810
2018-03-18 20:11:02 +00:00
Jan Kratochvil 2ccddfe3c6 DWARFUnit split out of DWARFCompileUnit
DW_TAG_partial_unit for DWZ can be then presented by DWARFPartialUnit also
inherited from DWARFUnit.

Differential revision: https://reviews.llvm.org/D40466

llvm-svn: 327809
2018-03-18 20:09:02 +00:00
Jan Kratochvil 50397237d9 refactor: DWARFCompileUnit::Producer -> DWARFProducer
Differential revision: https://reviews.llvm.org/D42891

llvm-svn: 324275
2018-02-05 21:50:01 +00:00
Jan Kratochvil ca9c2b290c refactor: Unify+simplify DWARFCompileUnit ctor+Clear() into in-class initializers + Extract()
It has no functionality effect.

I was concerned about the worse performance of DWARFDebugInfo::Parse this way
of allocating+destroying a CU for each iteration but I see it is now used only
by DWARFDebugInfo::Dump so that is no longer a problem.

Differential revision: https://reviews.llvm.org/D40212

llvm-svn: 319359
2017-11-29 21:13:11 +00:00
Jan Kratochvil d7ff94f035 Add comments to DWARFCompileUnit length fields/methods
Differential revision: https://reviews.llvm.org/D40211

llvm-svn: 318626
2017-11-19 14:35:07 +00:00
Tamas Berghammer 2540a553e5 Add support for DW_AT_ranges_base attribute
It is a new attribute emitted by clang as a GNU extension and will
be part of Dwarf5. The purpose of the attribute is to specify a compile
unit level base value for all DW_AT_ranges to reduce the number of
relocations have to be done by the linker.

Fixes (at least partially): https://llvm.org/pr28826

Differential revision: https://reviews.llvm.org/D24514

llvm-svn: 281595
2016-09-15 08:53:33 +00:00
Kate Stone b9c1b51e45 *** This commit represents a complete reformatting of the LLDB source code
*** to conform to clang-format’s LLVM style.  This kind of mass change has
*** two obvious implications:

Firstly, merging this particular commit into a downstream fork may be a huge
effort.  Alternatively, it may be worth merging all changes up to this commit,
performing the same reformatting operation locally, and then discarding the
merge for this particular commit.  The commands used to accomplish this
reformatting were as follows (with current working directory as the root of
the repository):

    find . \( -iname "*.c" -or -iname "*.cpp" -or -iname "*.h" -or -iname "*.mm" \) -exec clang-format -i {} +
    find . -iname "*.py" -exec autopep8 --in-place --aggressive --aggressive {} + ;

The version of clang-format used was 3.9.0, and autopep8 was 1.2.4.

Secondly, “blame” style tools will generally point to this commit instead of
a meaningful prior commit.  There are alternatives available that will attempt
to look through this change and find the appropriate prior commit.  YMMV.

llvm-svn: 280751
2016-09-06 20:57:50 +00:00
Tamas Berghammer 87a9769e9b Add a set of new plugins to handle Java debugging
The purpose of these plugins is to make LLDB capable of debugging java
code JIT-ed by the android runtime.

Differential revision: http://reviews.llvm.org/D17616

llvm-svn: 262015
2016-02-26 14:21:23 +00:00
Tamas Berghammer eb882fc1f8 Add basic fission support to SymbolFileDWARF
* Create new dwo symbol file class
* Add handling for .dwo sections
* Change indexes in SymbolFileDWARF to store compile unit offset next to
  DIE offset
* Propagate queries from dwarf compile unit to the dwo compile unit
  where applicable

Differential revision: http://reviews.llvm.org/D12291

llvm-svn: 247132
2015-09-09 10:20:48 +00:00
Tamas Berghammer 715cbe8939 Code cleanup in preparation of adding split dwarf support
* Remove some unused code
* Remove usage of DWARFDebugInfoEntry::Attributes where usage isn't
  reasonable
* Cleanup DWARFMappedHash with separating it to header and implementation
  file and fixing the visibility of the functions

Differential revision: http://reviews.llvm.org/D12374

llvm-svn: 247131
2015-09-09 10:20:36 +00:00
Greg Clayton 5ce1a84f9a More cleanup to make sure no one plays with DWARFDebugInfoEntry. Clients outside of DWARFDebugInfoEntry of DWARFCompileUnit should use DWARFDIE only.
llvm-svn: 246172
2015-08-27 18:09:44 +00:00
Greg Clayton 6071e6fc94 Major DWARF cleanup.
Added a new class called DWARFDIE that contains a DWARFCompileUnit and DWARFDebugInfoEntry so that these items always stay together.

There were many places where we just handed out DWARFDebugInfoEntry pointers and then use them with a compile unit that may or may not be the correct one. Clients outside of DWARFCompileUnit and DWARFDebugInfoEntry should all be dealing with DWARFDIE instances instead of playing with DWARFCompileUnit/DWARFDebugInfoEntry pairs manually.

This paves to the way for some modifications that are coming for DWO.

llvm-svn: 246100
2015-08-26 22:57:51 +00:00
Tamas Berghammer c178d4c0ce Add support for DW_FORM_GNU_[addr,str]_index
These are 2 new value currently in experimental status used when split
debug info is enabled.

Differential revision: http://reviews.llvm.org/D12238

llvm-svn: 245931
2015-08-25 11:45:58 +00:00
Jason Molenda c709958572 Move the computation of whether a DWARF compile unit
is optimized into DWARFCompileUnit, where it should have
been.  Next I'll need to call this from another section 
of code for DWARF-in-.o-file behavior correctness.

llvm-svn: 243736
2015-07-31 05:47:00 +00:00
Dawn Perchik d0e87eb07e Fix enum LanguageType values and language string table lookups.
Summary:
* Fix enum LanguageType values so that they can be used as indexes
into array language_names and g_languages as assumed by
LanguageRuntime::GetNameForLanguageType,
Language::SetLanguageFromCString and Language::AsCString.
* Add DWARFCompileUnit::LanguageTypeFromDWARF to convert from DWARF
DW_LANG_* values to enum LanguageType values.

Reviewed By: clayborg, abidh
Differential Revision: http://reviews.llvm.org/D10484

llvm-svn: 239963
2015-06-17 22:30:24 +00:00
Siva Chandra 0783ab9a7f [DWARF] If linkages names are missing, use decl context to get qualified names.
Summary:
This commit adds this alternate route only when parsing variable dies
corresponding to global or static variables. The motivation for this is that GCC
does not emit linkage names for functions and variables declared/defined in
anonymous namespaces. Having this alternate route fixes one part of
TestNamespace which fails when the test case is compiled with GCC.

An alternate route to get fully qualified names of functions whose linkage names
are missing will be added with a followup change. With that, the other failing
part of TestNamespace will also be fixed.

Test Plan: dotest.py -C gcc -p TestNamespace

Reviewers: clayborg

Reviewed By: clayborg

Subscribers: lldb-commits

Differential Revision: http://reviews.llvm.org/D8569

llvm-svn: 233098
2015-03-24 18:32:27 +00:00
Todd Fiala ee8bfc687f DWARF64 Fixes
1. DW_FORM_strp and DW_FORM_sec_offset are 64bits for DWARF64 / 32bits for DWARF32
They are different from DW_FORM_addr, whose size is specified in .debug_info

2. Bump DWARF version support form [2,3] to [2,4] in DWARFDebugLine.cpp

3. Fix DWARFDebugLine to support DWARF64

See http://reviews.llvm.org/D5307 for more details.
Reviewed by Greg Clayton and Jason Molenda.

Change by Tong Shen.

llvm-svn: 217607
2014-09-11 17:29:12 +00:00
Greg Clayton 26c1fe3568 Parse DW_AT_ranges for compile units on Darwin when .debug_aranges is not available for the current compile unit.
<rdar://problem/16321434> 

llvm-svn: 203985
2014-03-14 23:36:38 +00:00
Ed Maste eeae72184b Introduce DWARFDataExtractor for 64-Bit DWARF parsing
Review: http://llvm-reviews.chandlerc.com/D2007
llvm-svn: 193368
2013-10-24 20:43:47 +00:00
Ed Maste 737e92b036 Remove unused DWARFCompileUnit::Extract variant
llvm-svn: 192893
2013-10-17 13:23:03 +00:00
Greg Clayton 7b0992d9cd After discussing with Chris Lattner, we require C++11, so lets get rid of the macros and just use C++11.
llvm-svn: 179805
2013-04-18 22:45:39 +00:00
Greg Clayton e01e07b6e7 Since we use C++11, we should switch over to using std::unique_ptr when C++11 is being used. To do this, we follow what we have done for shared pointers and we define a STD_UNIQUE_PTR macro that can be used and it will "do the right thing". Due to some API differences in std::unique_ptr and due to the fact that we need to be able to compile without C++11, we can't use move semantics so some code needed to change so that it can compile with either C++.
Anyone wanting to use a unique_ptr or auto_ptr should now use the "STD_UNIQUE_PTR(TYPE)" macro.

llvm-svn: 179779
2013-04-18 18:10:51 +00:00
Greg Clayton c7bece56fa <rdar://problem/13069948>
Major fixed to allow reading files that are over 4GB. The main problems were that the DataExtractor was using 32 bit offsets as a data cursor, and since we mmap all of our object files we could run into cases where if we had a very large core file that was over 4GB, we were running into the 4GB boundary.

So I defined a new "lldb::offset_t" which should be used for all file offsets.

After making this change, I enabled warnings for data loss and for enexpected implicit conversions temporarily and found a ton of things that I fixed.

Any functions that take an index internally, should use "size_t" for any indexes and also should return "size_t" for any sizes of collections.

llvm-svn: 173463
2013-01-25 18:06:21 +00:00
Greg Clayton 37c36e486e <rdar://problem/12636970>
Detect the new fixed clang that properly supports bitfields in objc classes.

llvm-svn: 168655
2012-11-27 00:59:26 +00:00
Greg Clayton c7f03b6155 <rdar://problem/10681814>
Fix DWARF parsing issue we can run into when using llvm-gcc based dSYM files.

Also fix the parsing of objective C built-in types (Class, id and SEL) so
they don't parse more information that is not needed due to the way they
are represented in DWARF.

llvm-svn: 148016
2012-01-12 04:33:28 +00:00
Greg Clayton 360f9a7663 <rdar://problem/10551280>
Fixed a crasher that can occur when parsing invalid DWARF.

llvm-svn: 147350
2011-12-29 19:47:20 +00:00
Greg Clayton 220a00772a Tested a theory on the where when we lookup things in the accelerator tables
that if we prefer the current compile unit, followed by any compile units that
already had their DIEs parsed, followed by the rest of the matches, that we
might save some memory. This turned out not to help much. The code is commented
out, but I want to check it in so I don't lose the code in case it could help
later.

Added the ability to efficiently find the objective C class implementation
when using the new .apple_types acclerator tables with the type flags. If the
type flags are not available, we default back to what we were doing before.

llvm-svn: 146250
2011-12-09 08:48:30 +00:00
Greg Clayton 1959df2c9c Shrink-to-fit our std::vector<DWARFDebugInfoEntry> collections and save 20%
to 30% of memory. The size doubling was killing us and we ended up with up to
just under 50% of empty capacity. Cleaning this up saves us a ton of memory.

llvm-svn: 145086
2011-11-22 21:35:27 +00:00
Greg Clayton 3b608422e8 Further performance improvements in the DWARF parser:
1 - the DIE collections no longer have the NULL tags which saves up to 25%
    of the memory on typical C++ code
2 - faster parsing by not having to run the SetDIERelations() function anymore
    it is done when parsing the DWARF very efficiently.

llvm-svn: 144983
2011-11-19 02:11:30 +00:00
Greg Clayton d4a2b37091 Huge memory and performance improvements in the DWARF parser.
Address ranges are now split up into two different tables: 
- one in DWARFDebugInfo that is compile unit specific
- one in each DWARFCompileUnit that has exact function DIE offsets

This helps keep the size of the aranges down since the main table will get
uniqued and sorted and have consecutive ranges merged. We then only parse the
compile unit one on demand once we have determined that a compile unit contains
the address in question. We also now use the .debug_aranges section if there 
is one instead of always indexing the DWARF manually.

NameToDIE now uses a UniqueCStringMap<dw_offset> map instead of a std::map.
std::map is very bulky as each node has 3 pointers and the key and value types.
This gets our NameToDIE entry down to 12 bytes each instead of 48 which saves
us a lot of memory when we have very large DWARF.

DWARFDebugAranges now has a smaller footprint for each range it contains to 
save on memory.

llvm-svn: 139557
2011-09-12 23:21:58 +00:00