Commit Graph

20 Commits

Author SHA1 Message Date
Greg Clayton eee309068e Fix .debug_aranges parsing issues.
When LLVM error handling was introduced to the parsing of the .debug_aranges it would cause major issues if any DWARFDebugArangeSet::extract() calls returned any errors. The code in DWARFDebugInfo::GetCompileUnitAranges() would end up calling DWARFDebugAranges::extract() which would return an error if _any_ DWARFDebugArangeSet had any errors, but it default constructed a DWARFDebugAranges object into DWARFDebugInfo::m_cu_aranges_up and populated it partially, and returned an error prior to finishing much needed functionality in the DWARFDebugInfo::GetCompileUnitAranges() function. Subsequent callers to this function would see that the DWARFDebugInfo::m_cu_aranges_up was actually valid and return this partially populated DWARFDebugAranges reference _and_ it would not be sorted or minimized.

This above bugs would cause an incomplete .debug_aranges parsing, it would skip manually parsing any compile units for ranges, and would not sort the DWARFDebugAranges in m_cu_aranges_up.

This bug would also cause breakpoints set by file and line to fail to set correctly if a symbol context for an address could not be resolved properly, which the incomplete and unsorted DWARFDebugAranges object that DWARFDebugInfo::GetCompileUnitAranges() returned would cause symbol context lookups resolved by address (breakpoint address) to fail to find any DWARF debug info for a given address.

This patch fixes all of the issues that I found:
- DWARFDebugInfo::GetCompileUnitAranges() no longer returns a "llvm::Expected<DWARFDebugAranges &>", but just returns a "const DWARFDebugAranges &". Why? Because this code contained a fallback that would parse all of the valid DWARFDebugArangeSet objects, and would check which compile units had valid .debug_aranges set entries, and manually build an address ranges table using DWARFUnit::BuildAddressRangeTable(). If we return an error because any DWARFDebugArangeSet has any errors, then we don't do any of this code. Now we parse all DWARFDebugArangeSet objects that have no errors, if any calls to DWARFDebugArangeSet::extract() return errors, we skip that DWARFDebugArangeSet so that we can use the fallback call to DWARFUnit::BuildAddressRangeTable(). Since DWARFDebugInfo::GetCompileUnitAranges() needs to parse what it can from the .debug_aranges and build address ranges tables for any compile units that don't have any .debug_aranges sets, everything now works as expected.
- Fix an issue where a DWARFDebugArangeSet contains multiple terminator entries. The LLVM parser and llvm-dwarfdump properly warn about this because it happens with linux compilers and linkers and was the original cause of the bug I am fixing here. We now correctly warn about this issue if "log enable dwarf info" is enabled, but we continue to parse the DWARFDebugArangeSet correctly so we don't lose data that is contained in the .debug_aranges section.
- DWARFDebugAranges::extract() no longer returns a llvm::Error because we need to be able to parse all of the valid DWARFDebugArangeSet objects. It also will correctly skip a DWARFDebugArangeSet object that has errors in the middle of the stream by setting the start offsets of each DWARFDebugArangeSet to be calculated by the previous DWARFDebugArangeSet::extract() calculated offset that uses the header which contains the length of the DWARFDebugArangeSet. This means if do we run into real errors while parsing individual DWARFDebugArangeSet objects, we can continue to parse the rest of the validly encoded DWARFDebugArangeSet objects in the .debug_aranges section. This will allow LLDB to parse DWARF that contains a possibly newer .debug_aranges set format than LLDB currently supports because we will error out for the parsing of the DWARFDebugArangeSet, but be able to skip to the next DWARFDebugArangeSet object using the "DWARFDebugArangeSet.m_header.length" field to calculate the next starting offset.

Tests were added to cover all new functionality.

Differential Revision: https://reviews.llvm.org/D99401
2021-03-29 15:34:36 -07:00
Jonas Devlieghere cdc514e4c6 [lldb] Update header guards to be consistent and compliant with LLVM (NFC)
LLDB has a few different styles of header guards and they're not very
consistent because things get moved around or copy/pasted. This patch
unifies the header guards across LLDB and converts everything to match
LLVM's style.

Differential revision: https://reviews.llvm.org/D74743
2020-02-17 23:15:40 -08:00
Pavel Labath fe79fbc99d DWARF: Remove unused includes from DWARFDebugAranges.h/cpp
llvm-svn: 363382
2019-06-14 13:21:57 +00:00
Zachary Turner 611d1f98c5 Delete more dead code.
All of this is code that is unreferenced.  Removing as much of
this as possible makes it more easy to determine what functionality
is missing and/or shared between LLVM and LLDB's DWARF interfaces.

llvm-svn: 356509
2019-03-19 20:08:56 +00:00
Zachary Turner aea0985814 Delete dead code.
Most of these are Dump functions that are never called, but there
is one instance of entire unused classes (DWARFDebugMacinfo and
DWARFDebugMacinfoEntry) which are also unreferenced in the codebase).

Differential Revision: https://reviews.llvm.org/D59276

llvm-svn: 356490
2019-03-19 18:06:32 +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
Pavel Labath b8093314ef Move RangeMap.h into Utility
Summary:
This file implements some general purpose data structures, and so it
belongs to the Utility module.

Reviewers: zturner, jingham, JDevlieghere, clayborg, espindola

Subscribers: emaste, mgorny, javed.absar, arichardson, MaskRay, lldb-commits

Differential Revision: https://reviews.llvm.org/D58970

llvm-svn: 355509
2019-03-06 14:41:43 +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
Pavel Labath 0611642f3a RangeMap.h: merge RangeDataArray and RangeDataVector
Summary:
The main difference between the classes was supposed to be the fact that
one is backed by llvm::SmallVector, and the other by std::vector.
However, over the years, they have accumulated various other differences
too.

This essentially removes the std::vector version, as that is pretty much
identical to llvm::SmallVector<T, 0>, and combines their interfaces. It
does not attempt to do a more significant refactoring, even though there
is still a lot of duplication in this file, as it is hard to tell which
quirk of some API is depended on by somebody (and, a previous, more
ambitious attempt at this in D16769 has failed).

I also add some tests, including one which demonstrates one of the
quirks/bugs of the API I have noticed in the process.

Reviewers: clayborg, teemperor, tberghammer

Subscribers: mgorny, JDevlieghere, lldb-commits

Differential Revision: https://reviews.llvm.org/D56170

llvm-svn: 350380
2019-01-04 07:14:17 +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
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
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 2215230040 Changed RangeMap over to use llvm::SmallVector and updated the RangeArray and the RangeDataArray to have an extra "unsigned N" template parameter. Updated the lldb_private::Block to use a RangeArray with a uint32_t for both the function base offset and block range size, and then a 1 for the small vector size since most lexical blocks in DWARF only have 1 range. Updates the DWARFDebugRanges RangeArray to use an unsigned of 2 since most blocks that have more than one range usually have 2. Also updated a DWARFDebugAranges to default their RangeArray to use a SmallVector with unsigned size of 1 since this will take care of the .o files when doing DWARF in .o files and since there really isn't any good size we can guess with.
llvm-svn: 141480
2011-10-08 06:59:54 +00:00
Greg Clayton ea3e7d5ccf Added more functionality to Range template classes in RangeMap.h and converted remaining DWARF areas that were using ranges over to this class. Also converted lldb_private::Block to use it.
llvm-svn: 141460
2011-10-08 00:49:15 +00:00
Greg Clayton cf0e4f0daf Re-organized the contents of RangeMap.h to be more concise and also allow for a Range, RangeArray, RangeData (range + data), or a RangeDataArray. We have many range implementations in LLDB and I will be converting over to using the classes in RangeMap.h so we can have one set of code that does ranges and searching of ranges.
Fixed up DWARFDebugAranges to use the new range classes.

Fixed the enumeration parsing to take a lldb_private::Error to avoid a lot of duplicated code. Now when an invalid enumeration is supplied, an error will be returned and that error will contain a list of the valid enumeration values.

llvm-svn: 141382
2011-10-07 18:58:12 +00:00
Greg Clayton c26e445403 Since we use address ranges a lot I added a templatized class that allows us to easily control the base address type, the size type, and the data that is stored with each range. It is designed to be populated by appending all needed items, then sorting the resulting list, and optionally minimizing the list when done. I adopted this new list in the DWARFDebugAranges for even further memory savings.
llvm-svn: 141352
2011-10-07 03:58:56 +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
Greg Clayton c685f8e540 So we can't use .debug_pubtypes as it, as designed, does not tell us about
all types in all compile units. I added a new kind of accelerator table to
the DWARF that allows us to index the DWARF compile units and DIEs in a way
that doesn't require the data to stay loaded. Currently when indexing the
DWARF we check if the compile unit had parsed its DIEs and if it hasn't we
index the data and free all of the DIEs so we can reparse later when we need
to after using one of our complete accelerator tables to determine we need
to reparse some DWARF. If the DIEs had already been parsed we leave them 
loaded. The new accelerator table uses the "const char *" pointers from our
ConstString class as the keys, and NameToDIE::Info as the value. This info
contains the compile unit index and the DIE index which means we are pointed
right to the DIE we need unlike the other DWARF accelerator tables that often
just point us to the compile unit we would find our answer in. 

llvm-svn: 113933
2010-09-15 04:15:46 +00:00
Greg Clayton 016a95eb04 Looking at some of the test suite failures in DWARF in .o files with the
debug map showed that the location lists in the .o files needed some 
refactoring in order to work. The case that was failing was where a function
that was in the "__TEXT.__textcoal_nt" in the .o file, and in the 
"__TEXT.__text" section in the main executable. This made symbol lookup fail
due to the way we were finding a real address in the debug map which was
by finding the section that the function was in in the .o file and trying to
find this in the main executable. Now the section list supports finding a
linked address in a section or any child sections. After fixing this, we ran
into issue that were due to DWARF and how it represents locations lists. 
DWARF makes a list of address ranges and expressions that go along with those
address ranges. The location addresses are expressed in terms of a compile
unit address + offset. This works fine as long as nothing moves around. When
stuff moves around and offsets change between the remapped compile unit base
address and the new function address, then we can run into trouble. To deal
with this, we now store supply a location list slide amount to any location
list expressions that will allow us to make the location list addresses into
zero based offsets from the object that owns the location list (always a
function in our case). 

With these fixes we can now re-link random address ranges inside the debugger
for use with our DWARF + debug map, incremental linking, and more.

Another issue that arose when doing the DWARF in the .o files was that GCC
4.2 emits a ".debug_aranges" that only mentions functions that are externally
visible. This makes .debug_aranges useless to us and we now generate a real
address range lookup table in the DWARF parser at the same time as we index
the name tables (that are needed because .debug_pubnames is just as useless).
llvm-gcc doesn't generate a .debug_aranges section, though this could be 
fixed, we aren't going to rely upon it.

Renamed a bunch of "UINT_MAX" to "UINT32_MAX".

llvm-svn: 113829
2010-09-14 02:20:48 +00:00
Chris Lattner 30fdc8d841 Initial checkin of lldb code from internal Apple repo.
llvm-svn: 105619
2010-06-08 16:52:24 +00:00