Commit Graph

136 Commits

Author SHA1 Message Date
Raphael Isemann 76e47d4887 [lldb][NFC] Use C++ versions of the deprecated C standard library headers
The C headers are deprecated so as requested in D102845, this is replacing them
all with their (not deprecated) C++ equivalent.

Reviewed By: shafik

Differential Revision: https://reviews.llvm.org/D103084
2021-05-26 12:46:12 +02:00
Jan Kratochvil 6d19c84cd9 [lldb] Improve invalid DWARF DW_AT_ranges error reporting
In D98289#inline-939112 @dblaikie said:
  Perhaps this could be more informative about what makes the range list
  index of 0 invalid? "index 0 out of range of range list table (with
  range list base 0xXXX) with offset entry count of XX (valid indexes
  0-(XX-1))" Maybe that's too verbose/not worth worrying about since
  this'll only be relevant to DWARF producers trying to debug their
  DWARFv5, maybe no one will ever see this message in practice. Just
  a thought.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D102851
2021-05-20 21:37:01 +02:00
Jan Kratochvil cf806d91d5 [lldb] Fix DWARF-5 DW_FORM_implicit_const (used by GCC)
Differential Revision: https://reviews.llvm.org/D98197
2021-03-09 10:23:05 +01:00
Jan Kratochvil 1b8fdaacf4 [nfc] [lldb] DWARFDebugInfoEntry::Extract(): reindent 2021-03-02 16:44:07 +01:00
Jan Kratochvil 61c29321b3 [lldb] DWARFDebugInfoEntry::Extract(): Print an error for unsupported DW_FORM_* 2021-03-02 16:39:04 +01:00
Jan Kratochvil 4096ae06f4 [lldb] Support DWARF-5 DW_FORM_line_strp (used by GCC)
LLDB has been failing on binaries produced by new GCC 11.0 with -gdwarf-5.

Differential Revision: https://reviews.llvm.org/D97721
2021-03-02 15:17:23 +01:00
David Blaikie 274afac9a1 lldb: Add support for DW_AT_ranges on DW_TAG_subprograms
gcc already produces debug info with this form
-freorder-block-and-partition
clang produces this sort of thing with -fbasic-block-sections and with a
coming-soon tweak to use ranges in DWARFv5 where they can allow greater
reuse of debug_addr than the low/high_pc forms.

This fixes the case of breaking on a function name, but leaves broken
printing a variable - a follow-up commit will add that and improve the
test case to match.

Differential Revision: https://reviews.llvm.org/D94063
2021-01-07 14:28:03 -08:00
Jan Kratochvil 24f07531a3 [lldb] Fix DW_AT_decl_file from DW_AT_specification from a different CU
This would be reproducible in future DWZ category of the testsuite as:
  Failed Tests (1):
    lldb-api :: python_api/symbol-context/two-files/TestSymbolContextTwoFiles.py

Differential Revision: https://reviews.llvm.org/D91014
2020-11-09 10:52:48 +01:00
Jan Kratochvil 4515d35f5c [lldb] Fix DW_TAG_GNU_call_site-DW_AT_low_pc as produced by GCC
D80519 <https://reviews.llvm.org/D80519>
added support for `DW_TAG_GNU_call_site` but
Bug 45886 <https://bugs.llvm.org/show_bug.cgi?id=45886>
found one case did not work.

There is:

  0x000000b1:     DW_TAG_GNU_call_site
                    DW_AT_low_pc  (0x000000000040111e)
                    DW_AT_abstract_origin (0x000000cc "a")
  ...
  0x000000cc:   DW_TAG_subprogram
                  DW_AT_name      ("a")
                  DW_AT_prototyped        (true)
                  DW_AT_low_pc    (0x0000000000401109)
                  ^^^^^^^^^^^^ - here it did overwrite the 'low_pc' variable containing value 0x40111e we wanted
                  DW_AT_high_pc   (0x0000000000401114)
                  DW_AT_frame_base        (DW_OP_call_frame_cfa)
                  DW_AT_GNU_all_call_sites        (true)

DW_TAG_GNU_call_site attributes order as produced by GCC:
0x000000b1:     DW_TAG_GNU_call_site
                  DW_AT_low_pc  (0x000000000040111e)
                  DW_AT_abstract_origin (0x000000cc "a")

clang produces the attributes in opposite order:
0x00000064:     DW_TAG_GNU_call_site
                  DW_AT_abstract_origin (0x0000002a "a")
                  DW_AT_low_pc  (0x0000000000401146)

Differential Revision: https://reviews.llvm.org/D81334
2020-06-09 13:41:41 +02:00
Jan Kratochvil fd31e60b8d [nfc] [lldb] Reduce GetAttributes's depth parameter usage
Clean the code up a bit for D81334.

Differential Revision: https://reviews.llvm.org/D81423
2020-06-09 13:41:06 +02:00
Pavel Labath 283658c978 [lldb/DWARF] Remove dead code in DWARFDebugInfoEntry
The dumping code is not used by anyone, and is a source of
inconsistencies with the llvm dwarf parser, as dumping is implemented at
a different level (DWARFDie) there.
2020-05-04 15:37:22 +02:00
Pavel Labath 7cfa74fc69 [lldb/DWARF] Trust CU DW_AT_low/high_pc information when building address tables
Summary:
The code in DWARFCompileUnit::BuildAddressRangeTable tries hard to avoid
relying on DW_AT_low/high_pc for compile unit range information, and
this logic is a big cause of llvm/lldb divergence in the lowest layers
of dwarf parsing code.

The implicit assumption in that code is that this information (as opposed to
DW_AT_ranges) is unreliable. However, I have not been able to verify
that assumption. It is definitely not true for all present-day
compilers (gcc, clang, icc), and it was also not the case for the
historic compilers that I have been able to get a hold of (thanks Matt
Godbolt).

All compiler included in my research either produced correct
DW_AT_ranges or .debug_aranges entries, or they produced no DW_AT_hi/lo
pc at all. The detailed findings are:
- gcc >= 4.4: produces DW_AT_ranges and .debug_aranges
- 4.1 <= gcc < 4.4: no DW_AT_ranges, no DW_AT_high_pc, .debug_aranges
  present. The upper version range here is uncertain as godbolt.org does
  not have intermediate versions.
- gcc < 4.1: no versions on godbolt.org
- clang >= 3.5: produces DW_AT_ranges, and (optionally) .debug_aranges
- 3.4 <= clang < 3.5: no DW_AT_ranges, no DW_AT_high_pc, .debug_aranges
  present.
- clang <= 3.3: no DW_AT_ranges, no DW_AT_high_pc, no .debug_aranges
- icc >= 16.0.1: produces DW_AT_ranges
- icc < 16.0.1: no functional versions on godbolt.org (some are present
  but fail to compile)

Based on this analysis, I believe it is safe to start trusting
DW_AT_low/high_pc information in dwarf as well as remove the code for
manually reconstructing range information by traversing the DIE
structure, and just keep the line table fallback. The only compilers
where this will change behavior are pre-3.4 clangs, which are almost 7
years old now. However, the functionality should remain unchanged
because we will be able to reconstruct this information from the line
table, which seems to be needed for some line-tables-only scenarios
anyway (haven't researched this too much, but at least some compilers
seem to emit DW_AT_ranges even in these situations).

In addition, benchmarks showed that for these compilers computing the
ranges via line tables is noticably faster than doing so via the DIE
tree.

Other advantages include simplifying the code base, removing some
untested code (the only test changes are recent tests with overly
reduced synthetic dwarf), and increasing llvm convergence.

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D78489
2020-04-23 16:12:41 +02:00
Davide Italiano ce7790044f [DWARF] Rename a function and comment it for clarity.
Pointed out by Adrian.
2020-04-16 15:37:09 -07:00
Davide Italiano d51b38f1b3 [DWARF] Not all the constant variables are "static".
Fixes rdar://problem/61402307

Differential Revision: https://reviews.llvm.org/D77698
2020-04-08 11:07:19 -07:00
Jan Kratochvil 1d11d5f624 [lldb] [NFC] Refactor GetDWARFDeclContext to return DWARFDeclContext
Suggested by Pavel Labath.

Differential Revision: https://reviews.llvm.org/D73787
2020-02-06 20:06:28 +01:00
Jan Kratochvil edc3f4f02e [NFC] [lldb] Unindent DWARFDebugInfoEntry::GetDWARFDeclContext
Reduce code indentation level.
2020-01-31 16:51:33 +01:00
Jan Kratochvil 6dd0163502 [lldb] Revert refactorization from: Move non-DWARF code: DWARFUnit -> SymbolFileDWARF
Reverting part of commit 789beeeca3.

Its DWARFDebugInfoEntry::GetDWARFDeclContext() refactorization for
return value is now adding it in opposite order.
2020-01-31 16:06:23 +01:00
Jan Kratochvil 789beeeca3 [lldb] Move non-DWARF code: DWARFUnit -> SymbolFileDWARF
This patchset is removing non-DWARF code from DWARFUnit for better
future merge with LLVM DWARF as discussed with @labath.

Differential revision: https://reviews.llvm.org/D70646
2020-01-31 15:16:31 +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
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 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 c8b74ee264 [lldb/DWARF] Add support for DW_AT_loclists_base&DW_FORM_loclistx
Summary:
This adds support for DWARF5 location lists which are specified
indirectly, via an index into the debug_loclists offset table. This
includes parsing the DW_AT_loclists_base attribute which determines the
location of this offset table, and support for new form DW_FORM_loclistx
which is used in conjuction with DW_AT_location to refer to the location
lists in this way.

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

Reviewers: JDevlieghere, aprantl, clayborg

Subscribers: lldb-commits

Tags: #lldb

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

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

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

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

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

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

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

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

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

Reviewers: JDevlieghere, aprantl, clayborg

Subscribers: dblaikie, lldb-commits

Tags: #lldb

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

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

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

Reviewers: JDevlieghere, aprantl, clayborg

Subscribers: dblaikie, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D71021
2019-12-05 13:02:03 +01:00
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 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
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 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 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
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 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
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 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 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
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
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
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
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
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
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
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