Commit Graph

339 Commits

Author SHA1 Message Date
James Henderson 720be5c016 [DebugInfo][test][NFC] Remove case numbers
This reduces the noise caused by adding cases earlier in the sequence.

Reviewed by: dblaikie

Differential Revision: https://reviews.llvm.org/D74402
2020-02-12 11:05:32 +00:00
Djordje Todorovic 97ed706a96 Revert "[DebugInfo] Enable the debug entry values feature by default"
This reverts commit rG9f6ff07f8a39.

Found a test failure on clang-with-thin-lto-ubuntu buildbot.
2020-02-12 11:59:04 +01:00
Djordje Todorovic 9f6ff07f8a [DebugInfo] Enable the debug entry values feature by default
This patch enables the debug entry values feature.

  - Remove the (CC1) experimental -femit-debug-entry-values option
  - Enable it for x86, arm and aarch64 targets
  - Resolve the test failures
  - Leave the llc experimental option for targets that do not
    support the CallSiteInfo yet

Differential Revision: https://reviews.llvm.org/D73534
2020-02-12 10:25:14 +01:00
Igor Kudrin 07e50c7b91 [DebugInfo] Add support for DWARF64 into DWARFDebugAddr.
Differential Revision: https://reviews.llvm.org/D74198
2020-02-12 13:33:01 +07:00
Igor Kudrin dc16612393 [DebugInfo] Simplify DWARFDebugAddr.
The patch removes unnecessary members of DWARFDebugAddr and further
simplifies the implementation by separating parsing methods of tables
in the DWARFv5 and pre-standard formats.

Differential Revision: https://reviews.llvm.org/D74197
2020-02-12 13:33:00 +07:00
Igor Kudrin de9604232a [DebugInfo] Refine error messages in DWARFDebugAddr.
As a preparation for the subsequent patches, this updates the wordings
of some error messages in DWARFDebugAddr.

Differential Revision: https://reviews.llvm.org/D74196
2020-02-12 13:33:00 +07:00
Igor Kudrin 292b67f993 [DebugInfo] Use "an address table" in diagnostic messages of DWARFDebugAddr.
This replaces a collocation "a .debug_addr table" with "an address table"
because the latter sounds more accurate.

Differential Revision: https://reviews.llvm.org/D74407
2020-02-12 13:33:00 +07:00
Igor Kudrin 675c4bebaf [DebugInfo] Do not dump header field for pre-DWARFv5 address tables.
As there is no header in pre-DWARFv5 address tables, and we fill
the class data members with some artificial values, we should not
dump them as that might be misleading.

Differential Revision: https://reviews.llvm.org/D74195
2020-02-12 13:33:00 +07:00
Igor Kudrin 5d58eb9f4f [DebugInfo] Fix reading addresses in DWARFDebugAddr.
As addresses in the address tables may have relocations, thus,
the relocations should be resolved to read the correct address.
That is especially important for targets that use RELA relocations
because in that case addends are stored in relocation sections.

Differential Revision: https://reviews.llvm.org/D74404
2020-02-12 13:32:59 +07:00
James Henderson 47f7df8946 [test][DebugInfo][NFC] Fix line endings 2020-02-11 16:11:40 +00:00
James Henderson 1dc62d0358 [DebugInfo][test] Replace pre-canned binary test
The DebugInfo/dwarfdump-invalid-line-table test used a pre-canned binary
generated by a fuzzer to demonstrate a bug fix. Unfortunately, the
binary is rigid and requires hand-editing if we change behaviour, such
as rejecting certain properties within it (as I plan on doing in another
change).

Rather than hand-edit the binary, I have replaced it with two tests. The
first tests the high-level code path from the debug line parser that
produces the same error as this test previously did, and the second is a
set of unit test cases that comprehensively cover the
FormValue::skipValue method, which in turn covers the area that the
original bug fix touched.

Reviewed by: MaskRay, dblaikie

Differential Revision: https://reviews.llvm.org/D74202
2020-02-10 13:54:40 +00:00
Igor Kudrin 1ea99a2ebc [DebugInfo] Allow reading an address table with a mismatched address.
This case does not look as an unrecoverable error.

Differential Revision: https://reviews.llvm.org/D74194
2020-02-08 20:00:03 +07:00
David Blaikie 9e8bff71d0 DebugInfo: Allow dumping macinfo and macinfo.dwo from the same file
If dumping an Split DWARF file that hasn't been split into separate
files (such as from llc - that includes the plain and .dwo sections in
the same file) allow both macinfo and macinfo.dwo sections to be dumped.
2020-01-31 12:47:50 -08:00
Adrian Prantl aa6ec19c5f Add dwarfdump support for DW_OP_regval_type.
Differential Revision: https://reviews.llvm.org/D73598
2020-01-29 10:02:23 -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
Kristina Bessonova 4b0a7fe008 [llvm-dwarfdump][Statistics] Make calculations of vars in global scope more accurate
It isn't known how many times we've seen the same variable or member in
the global scope (unlike in functions), but there still can be some duplicates
among different CUs.
So, this patch proposes to count variables in the global scope just as a sum of
the number of vars, constant members and artificial entities.

Reviewed by: aprantl

Differential Revision: https://reviews.llvm.org/D73004
2020-01-28 20:52:20 +02:00
Kristina Bessonova 5499e2f455 [llvm-dwarfdump][Statistics] Distinguish parameters with same name or w/o a name
A few DW_TAG_formal_parameter's of the same function may have the same
name (e.g. variadic (template) functions) or don't have a name at all
(if the parameter isn't used inside the function body), but we still
need to be able to distinguish between them to get correct number of 'total vars'
and 'availability' metric.

Reviewed by: aprantl

Differential Revision: https://reviews.llvm.org/D73003
2020-01-28 20:52:20 +02:00
Kristina Bessonova 57839e5178 [llvm-dwarfdump][Statistics] Count more than one conrete out-of-line instances of a function
Here may be more than one out-of-line instance of the same function
among different CUs. All of them should be accounted for to get an accurate
total number of variables/parameters.

Reviewed by: aprantl

Differential Revision: https://reviews.llvm.org/D73002
2020-01-28 20:52:19 +02:00
Kristina Bessonova 2e5d20bd47 [llvm-dwarfdump][Statistics] Ignore declarations of global variables
Reviewed by: djtodoro

Differential Revision: https://reviews.llvm.org/D73001
2020-01-28 19:50:46 +02:00
Kristina Bessonova e76106e01c [llvm-dwarfdump][Statistics] Ignore DW_TAG_subroutine_type in statistics
DW_TAG_subroutine_type is not really useful for statistics purposes, as it never
has location information. But it may contain DW_TAG_formal_parameter
children that generate number of parameters w/o location and decrease
'availability' metric significantly.

Reviewed by: djtodoro

Differential Revision: https://reviews.llvm.org/D72983
2020-01-28 19:50:46 +02:00
Kristina Bessonova 9806b39dae [llvm-dwarfdump][Statistics] Distinguish functions/variables with same name across different CUs
Different variables and functions might have the same name in different CU.
To calculate 'Availability' metric more accurate (i.e. to avoid getting
availability above 100%), we need to have some additional logic to
distinguish between them.

The patch introduces a DIE identifier that consists of a function/variable name
and declaration information: a filename and a line number. This allows
distinguishing different functions/variables (different means declared in
different files/lines) with the same name, keeping duplicates counted
as duplicates.

Reviewed by: aprantl, djtodoro

Differential Revision: https://reviews.llvm.org/D72797
2020-01-28 19:50:46 +02:00
James Henderson 5c05165984 Revert "[DebugInfo] Make most debug line prologue errors non-fatal to parsing"
This reverts commit b94191fecd.

The change broke both an LLD test and the LLDB build.
2020-01-28 11:49:30 +00:00
James Henderson b94191fecd [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 "the
claimed length is correct" is taken to be consistent with other
instances such as the SectionParser, which ignores the read length.

Reviewed by: dblaikie

Differential Revision: https://reviews.llvm.org/D72158
2020-01-28 11:29:50 +00:00
James Henderson c963b5fbd6 [test][llvm-dwarfdump] Add extra test case for invalid MD5 form
A subsequent patch will change how an invalid file name table is handled
to allow parsing to continue. This patch adds a test case that will
demonstrate a difference in behaviour with that change between invalid
file tables where the error is before the end of the stated prologue
length and where the error occurs after the stated length.

Reviewed by: dblaikie

Differential Revision: https://reviews.llvm.org/D72157
2020-01-27 15:33:34 +00:00
James Henderson f1be770ff6 [DebugInfo] Make incorrect debug line extended opcode length non-fatal
It is possible to try to keep parsing a debug line program even when the
length of an extended opcode does not match what is expected for that
opcode. This patch changes what was previously a fatal error to be
non-fatal. The parser now continues by assuming the the claimed length
is correct, even if it means moving the offset backwards.

Reviewed by: dblaikie

Differential Revision: https://reviews.llvm.org/D72155
2020-01-27 15:32:41 +00:00
Igor Kudrin dcff3961c2 [DWARF] Return Error from DWARFDebugArangeSet::extract().
This helps to detect and report parsing errors better.
The patch follows the ideas of LLDB's patches D59370 and D59381.

It adds tests for valid and some invalid cases. More checks and
tests to come. Note that the patch fixes validation of the Length
field because the value does not include the field itself.

The existing users are updated to show the error messages.

Differential Revision: https://reviews.llvm.org/D71875
2020-01-23 12:41:05 +07:00
Hubert Tong 63b428e386 DWARFDebugLine.cpp: Format unknown line number standard opcodes
Summary:
This patch implements `formatv()` formatting for `dwarf::LineNumberOps`
and makes use of it for the `llvm-dwarfdump --debug-line` dump.

Previously, unknown line number standard opcodes would lead to undefined
behaviour. The code would attempt to format the data pointer of an empty
`StringRef` (a null pointer) using `%s`. According to the description
for `format()`, use of that interface carries the "risk of `printf`".
Passing a null pointer in place of an array to a C library function
results in undefined behaviour.

Reviewers: jhenderson, daltenty, stevewan

Reviewed By: jhenderson

Subscribers: aprantl, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D72369
2020-01-15 10:45:50 -05:00
James Henderson 6e3ca962fa [DebugInfo] Improve error message text
Unlike most of our errors in the debug line parser, the "no end of
sequence" message was missing any reference to which line table it
refererred to. This change adds the offset to this message.

Reviewed by: dblaikie

Differential Revision: https://reviews.llvm.org/D72443
2020-01-10 14:59:58 +00:00
James Henderson 418cd8216b [DebugInfo] Remove redundant checks for past-the-end of prologue
The V5 directory and filename tables had checks in to make sure we
hadn't read past the end of the line table prologue. Since previous
changes to the data extractor class ensure we never read past the end,
these checks are now redundant, so this patch removes them.

There is still a check to show that the whole prologue remains within
the prologue length.

Reviewed By: JDevlieghere

Differential Revision: https://reviews.llvm.org/D71768
2020-01-03 12:35:32 +00:00
James Henderson 7b4badf6f9 [test][llvm-dwarfdump] Use --implicit-check-not to simplify test checks
This removes the need to duplicate the LASTONLY check pattern and the
last part of the NONFATAL pattern in the modified test.

Reviewed By: MaskRay, JDevlieghere

Differential Revision: https://reviews.llvm.org/D71757
2020-01-03 11:22:20 +00:00
James Henderson f6f0cb4fd1 [test][llvm-dwarfdump] Normalise contents and checks for line tables
The line tables in debug_line_malformed.s had contents that varied more
than was necessary for the testing, making it harder to follow what was
important. This patch normalises them so that they all share
more-or-less the same body. Additionally, it makes the testing for what
was printed more consistent, to show that the right parts of the line
table prologue and body are/are not parsed and printed.

Reviewed By: JDevlieghere

Differential Revision: https://reviews.llvm.org/D71755
2020-01-03 11:19:00 +00:00
James Henderson 91cbcbd9e5 [test][llvm-dwarfdump] Add missing checks for table dumping
Some of the tables in debug_line_malformed.s were not being checked in
the NONFATAL checks in debug_line_invalid.test (only the warnings coming
from them were being checked). This made the test harder to follow.
Additionally, a later change will change the way the errors are handled
such that more of the line table will be printed. That will require
checks for these tables (or something equivalent) so that the difference
in behaviour can be observed. This patch adds checks for the three
tables that were missing checks.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D71753
2020-01-03 11:06:31 +00:00
James Henderson 19a71e358e [test][llvm-dwarfdump][NFC] Remove unused check
Reviewed by: JDevlieghere

Differential Revision: https://reviews.llvm.org/D71756
2020-01-02 17:05:37 +00:00
James Henderson 0ae9e952f7 [test][llvm-dwarfdump][NFC] Improve test readability
This patch adds and improves comments in the debug_line_invalid.test and
its associated input file so that it is easier to follow. It uses '##'
to make comments stand out from lit and FileCheck commands.

It also reflows some commands so that the lines are not so long and are
easier to read and fixes some copy/paste errors.

Reviewed by: JDevlieghere

Differential Revision: https://reviews.llvm.org/D71752
2020-01-02 16:59:09 +00:00
David Blaikie 199700a5cf DebugInfo: Support dumping any exprloc as an expression
Now that DWARFv5 provides a way to identify DWARF expressions based on
form, rather than only by attribute - use it to always provide pretty
printing for any exprloc attribute, not only the attributes known to
contain expressions.
2019-12-23 19:18:47 -08:00
James Henderson 60cb33c9b8 [DebugInfo] Fix verbose printing of rows added via DW_LNE_end_sequence
The debug line verbose printing was printing the wrong values for rows
added via DW_LNE_end_sequence, because the row was being printed AFTER
its state had been reset following it being appended to the line table.
This patch fixes this issue by printing the row before appending it.

Reviewers: dblaikie, MaskRay

Differential Revision: https://reviews.llvm.org/D71664
2019-12-19 12:54:04 +00:00
David Blaikie eed0242330 DebugInfo: Don't use implicit zero addr_base
(found when LLVM fails to emit addr_base for gmlt+DWARFv5)
2019-12-18 16:28:19 -08:00
James Henderson 5666b70fd0 [DebugInfo] Only print a single blank line after an empty line table
Commit 84a9756 added an extra blank line at the end of any line table.
However, a blank line is also printed after the line table header, which
meant that two blank lines in a row were being printed after a header,
if there were no rows. This patch defers the post-header blank line
printing until it has been determined that there are rows to print.

Reviewed by: dblaikie

Differential Revision: https://reviews.llvm.org/D71540
2019-12-17 12:04:09 +00:00
Kristina Bessonova d5655c4d2e [llvm-dwarfdump][Statistics] Don't count coverage less than 1% as 0%
Summary:
This is a follow up for D70548.
Currently, variables with debug info coverage between 0% and 1% are put into
zero-bucket. D70548 changed the way statistics calculate a variable's coverage:
we began to use enclosing scope rather than a possible variable life range.
Thus more variables might be moved to zero-bucket despite they have some debug
info coverage.
The patch is to distinguish between a variable that has location info but
it's significantly less than its enclosing scope and a variable that doesn't
have it at all.

Reviewers: djtodoro, aprantl, dblaikie, avl

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71070
2019-12-13 17:34:58 +03:00
Kristina Bessonova 1cc4b603ba [llvm-dwarfdump][Statistics] Change the coverage buckets representation. NFC
Summary:
This changes the representation of 'coverage buckets' in llvm-dwarfdump and
llvm-locstats to one that makes more clear what the buckets contain.

See some related details in D71070.

Reviewers: djtodoro, aprantl, cmtice, jhenderson

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71366
2019-12-13 16:08:25 +03:00
James Henderson 84a9756a72 [llvm-dwarfdump] Add blank line after printing line table
This helps delineate it in the output from later tables or other output.

Reviewed by: JDevlieghere

Differential Revision: https://reviews.llvm.org/D71344
2019-12-12 14:06:10 +00:00
James Henderson 5224feb7ca [test][llvm-dwarfdump] Add missing testing for some --debug-* options
A number of the --debug-* options in llvm-dwarfdump are not particularly
well tested. In some cases, the option is only tested as part of testing
another feature, or a specific part of the section that the options
dump. This change adds four new tests to address some of these holes. It
is not aiming to address every hole however.

I kept the --debug-line switch test separate to X86/brief.s because the
latter only considers the parts of the line table that are affected by
verbose printing, thus missing out things like the header and different
values for things like the Line, Column etc registers.

Reviewed by: JDevlieghere

Differential Revision: https://reviews.llvm.org/D71276
2019-12-11 13:42:54 +00:00
Luís Marques 707e970781 [DWARF][RISCV] Test resolving of RISC-V relocations
Summary: This patch adds an object file (in yaml format) with a synthetic
.debug_info section which we use to test that the supported RISC-V relocations
are properly resolved.

Reviewers: asb, lenary, MaskRay
Reviewed By: MaskRay
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70541
2019-12-10 14:02:07 +00:00
Jonas Devlieghere d9466653e4 [llvm/dwarfdump] Use the architecture string to filter.
Currently dwarfdump uses the ArchType to filter out architectures, which
is problematic for architectures like arm64e and x86_64h that map back
to arm64 and x86_64 respectively. The result is that the filter doesn't
work for these architectures because it matches all the variants. This
is especially bad because usually these architectures are the reason to
use the filter in the first place.

Instead, we should match the architecture based on the string name. This
means the filter works for the values printed by dwarfdump. It has the
unfortunate side effect of not working for aliases, like AArch64, but I
think that's worth the trade-off.

rdar://53653014

Differential revision: https://reviews.llvm.org/D71230
2019-12-09 17:17:01 -08:00
Kristina Bessonova 68f464ac2e [llvm-dwarfdump][Statistics] Unify coverage statistic computation
Summary:
The patch removes OffsetToFirstDefinition in the 'scope bytes total'
statistic computation. Thus it unifies the way the scope and the coverage
buckets are computed. The rationals behind that are the following:

1. OffsetToFirstDefinition was used to calculate the variable's life range.
However, there is no simple way to do it accurately, so the scope calculated
this way might be misleading. See D69027 for more details on the subject.
2. Both 'scope bytes total' and coverage buckets seem to be intended
to represent the same data in different ways. Otherwise, the statistics
might be controversial and confusing.

Note that the approach gives up a thorough evaluation of debug information
completeness (i.e. coverage buckets by themselves doesn't tell how good
the debug information is). Only changes in coverage over time make
a 'physical' sense.

Reviewers: djtodoro, aprantl, vsk, dblaikie, avl

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70548
2019-12-08 15:46:49 +03:00
Pavel Labath 4ee76a922a [llvm/DWARF] Return section offset from DWARFUnit::get{Loc,Rng}listOffset
Summary:
Currently these function return the raw content of the appropriate table
header, which means they are relative to the DW_AT_{loc,rng}list_base,
and one has to relocate them in order to do anything.

This changes the functions to perform the relocation themselves, which
seems more clearer, particularly as they are sitting right next to the
find{Rng,Loc}listFromOffset functions, but one *cannot* simply take the
result of these functions and take pass them there.

The only effect of this patch is to change what value is dumped for the
DW_AT_ranges attribute, which I think is for the better, as previously
the values appeared to point into thin air.

(The main reason I am looking at this is because I was trying to
implement equivalent functionality in lldb's DWARFUnit, and was stumped
by this behavior.

Reviewers: dblaikie, JDevlieghere, aprantl

Subscribers: hiraditya, llvm-commits, SouraVX

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71006
2019-12-05 12:35:09 +01:00
Pavel Labath a3af3ac393 [DWARFDebugLoclists] Add support for other DW_LLE encodings
Summary:
lldb's loclists parser has support for DW_LLE_start_end(x) encodings. To
avoid regressing when switching the implementation to llvm's, I add
parsing support for all previously unsupported location list encodings.

Reviewers: dblaikie, JDevlieghere, aprantl, SouraVX

Subscribers: hiraditya, probinson, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70949
2019-12-04 10:38:21 +01:00
Pavel Labath 1fbe8a82e1 [DWARF] Add support for parsing/dumping section indices in location lists
Summary:
This does exactly what it says on the box. The only small gotcha is the
section index computation for offset_pair entries, which can use either
the base address section, or the section from the offset_pair entry.
This is to support both the cases where the base address is relocated
(points to the base of the CU, typically), and the case where the base
address is a constant (typically zero) and relocations are on the
offsets themselves.

Reviewers: dblaikie, JDevlieghere, aprantl, SouraVX

Subscribers: hiraditya, llvm-commits, probinson

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70540
2019-12-03 11:48:28 +01:00
Pavel Labath 01bb3b07c3 [DWARFVerifier] Use the new location list api
Summary:
Instead of going to the debug_loc section directly, use new
DWARFDie::getLocations instead. This means that the code will now
automatically support debug_loclists sections.

This is the last usage of the old debug_loc methods, and they can now be
removed.

Reviewers: dblaikie, JDevlieghere, aprantl, SouraVX

Subscribers: hiraditya, probinson, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70534
2019-11-22 10:08:39 +01:00
Pavel Labath f65cfff605 dwarfdump --statistics: Use new location list api
Summary:
This patch removes manual location list handling in the statistics code
and replaces it with the new DWARFDie api, which provides access to a
"cooked" location list. This has the following effects:
- the code now properly handles split-dwarf location lists
- it will automatically support dwarf5 location lists once support for
  those is added
- it properly handles location lists with base address selection entries
- it fixes a bug where the location list code was using the first
  DW_AT_ranges range as a "base address" of the compile unit (it should
  have used DW_AT_low_pc instead. The effect of this was that the
  computation of the start address of a variable in its scope was broken
  for these kinds of compile units. This only manifested itself on
  linked files, since in object files the first DW_AT_ranges range
  normally starts at 0.

Since pretty much every kind of location list was broken in some way,
it's hard to verify that the new implementation is correct -- the output
will be different in all non-trivial cases, and mostly with good reason.

Most of the existing statistics tests continue to pass though, and a
visual inspection of the statistics for non-trivial inputs shows that
the data is more "reasonable" now. I have updated the "dwo statistics"
test to include the new numbers, as the previous ones were completely
bogus, and I have added a targeted test for the "base address" bug.

Reviewers: dblaikie, cmtice, vsk

Subscribers: aprantl, SouraVX, JDevlieghere, djtodoro, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70444
2019-11-21 11:55:21 +01:00
Djordje Todorovic 979592a6f7 [DebugInfo] Remove the DIFlagArgumentNotModified debug info flag
Due to changes in D68206, we remove the DIFlagArgumentNotModified
and its usage.

Differential Revision: https://reviews.llvm.org/D68207
2019-11-20 13:18:40 +01:00
Pavel Labath fa54186056 [NFC] Clean up debug-names-verify-completeness.s test
This patch replaces the tabs by spaces and avoid the need for a
debug_str section by moving all strings inline. It also removes the
hardcoded DIE offsets in the test, which will simplify a follow-up
patch.
2019-11-18 16:33:29 +01:00
Pavel Labath 0908093977 DWARFDebugLoc(v4): Add an incremental parsing function
Summary:
This adds a visitLocationList function to the DWARF v4 location lists,
similar to what already exists for DWARF v5. It follows the approach
outlined in previous patches (D69672), where the parsed form is always
stored in the DWARF v5 format, which makes it easier for generic code to
be built on top of that. v4 location lists are "upgraded" during
parsing, and then this upgrade is undone while dumping.

Both "inline" and section-based dumping is rewritten to reuse the
existing "generic" location list dumper. This means that the output
format is consistent for all location lists (the only thing one needs to
implement is the function which prints the "raw" form of a location
list), and that debug_loc dumping correctly processes base address
selection entries, etc.

The previous existing debug_loc functionality (e.g.,
parseOneLocationList) is rewritten on top of the new API, but it is not
removed as there is still code which uses them. This will be done in
follow-up patches, after I build the API to access the "interpreted"
location lists in a generic way (as that is what those users really
want).

Reviewers: dblaikie, probinson, JDevlieghere, aprantl, SouraVX

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69847
2019-11-15 13:38:00 +01:00
Pavel Labath eafe0cf5fa DWARFDebugLoclists: stricter base address handling
Summary:
This removes the use of zero as a base address in section-based dumping.
Although this will often be true for (unlinked) object files with a
single compile unit, it is not true in general. This means that
section-based dumping will not be able to resolve entries referencing
the base address (DW_LLE_offset_pair) -- it wasn't able to do that
correctly before either, but now it will be more explicit about it. One
exception to that is if the location list contains an explicit
DW_LLE_base_address entry -- in this case the dumper will pick it up,
and resolve subsequent entries normally.

The patch also removes the fallback to zero in the "inline" dumping in
case the compile unit does not contain a base address.

Reviewers: dblaikie, probinson, JDevlieghere, aprantl, SouraVX

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70115
2019-11-14 10:01:48 +01:00
Pavel Labath ebe2f56030 DWARFDebugLoclists: add location list "interpretation" logic
Summary:
This patch extracts the logic for computing the "absolute" locations,
which was partially present in the debug_loclists dumper, completes it,
and moves it into a separate function. This makes it possible to later
reuse the same logic for uses other than dumping.

The dumper is changed to reuse the location list interpreter, and its
format is changed somewhat. In "verbose" mode it prints the "raw" value
of a location list, the interpreted location (if available) and the
expression itself. In non-verbose mode it prints only one of the
location forms: it prefers the interpreted form, but falls back to the
"raw" format if interpretation is not possible (for instance, because we
were not given a base address, or the resolution of indirect addresses
failed).

This patch also undos some of the changes made in D69672, namely the
part about making all functions static. The main reason for this is that
I learned that the original approach (dumping only fully resolved
locations) meant that it was impossible to rewrite one of the existing
tests. To make that possible (and make the "inline location" dump work
in more cases), I now reuse the same dumping mechanism as is used for
section-based dumping. As this required having more objects know about
the various location lists classes, it seemed like a good idea to create
an interface abstracting the difference between them.

Therefore, I now create a DWARFLocationTable class, which will serve as
a base class for the location list classes. DWARFDebugLoclists is made
to inherit from that. DWARFDebugLoc will follow.

Another positive effect of this change is that section-based dumping
code will not need to use templates (as originally) envisioned, and that
the argument lists of the dumping functions become shorter.

Reviewers: dblaikie, probinson, JDevlieghere, aprantl, SouraVX

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70081
2019-11-12 10:40:13 +01:00
Pavel Labath e1f8c8a16f DWARFDebugLoclists: Move to a incremental parsing model
Summary:
This patch stems from the discussion D68270 (including some offline
talks). The idea is to provide an "incremental" api for parsing location
lists, which will avoid caching or materializing parsed data. An
additional goal is to provide a high level location list api, which
abstracts the differences between different encoding schemes, and can be
used by users which don't care about those (such as LLDB).

This patch implements the first part. It implements a call-back based
"visitLocationList" api. This function parses a single location list,
calling a user-specified callback for each entry. This is going to be
the base api, which other location list functions (right now, just the
dumping code) are going to be based on.

Future patches will do something similar for the v4 location lists, and
add a mechanism to translate raw entries into concrete address ranges.

Reviewers: dblaikie, probinson, JDevlieghere, aprantl, SouraVX

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69672
2019-11-06 16:25:06 +01:00
Pavel Labath b4c5b8f3f5 DWARFDebugLoclists: Make it possible to read relocated addresses
Summary:
Handling relocations was not needed when the loclists section was a
DWO-only thing. But since DWARF5, it is possible to use it in regular
objects too, and the standard permits embedding addresses into the
section directly. These addresses need to be relocated in unlinked
files.

Reviewers: JDevlieghere, dblaikie, probinson

Subscribers: aprantl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68271
2019-11-05 10:21:39 +01:00
George Rimar 2bf01dcbaa [llvm/Object] - Make ELFObjectFile::getRelocatedSection return Expected<section_iterator>
It returns just a section_iterator currently and have a report_fatal_error call inside.
This change adds a way to return errors and handle them on caller sides.

The patch also changes/improves current users and adds test cases.

Differential revision: https://reviews.llvm.org/D69167

llvm-svn: 375408
2019-10-21 11:06:38 +00:00
David Blaikie f358c3d371 llvm-dwarfdump: Add verbose printing for debug_loclists
llvm-svn: 374582
2019-10-11 19:06:35 +00:00
David Blaikie 411497c6c7 llvm-dwarfdump: Support multiple debug_loclists contributions
Also fixing the incorrect "offset" field being computed/printed for each
location list.

llvm-svn: 374232
2019-10-09 21:25:28 +00:00
Djordje Todorovic 45297645aa [llvm-dwarfdump] Fix dumping of wrong locstats map
llvm-svn: 373469
2019-10-02 13:24:45 +00:00
Diana Picus c2c377ea58 Fixup r373278: Move test to X86 directory
...since it's using an x86 triple.

llvm-svn: 373314
2019-10-01 09:27:20 +00:00
David Blaikie 5ca306666c DebugInfo: Add parsing support for debug_loc base address specifiers
llvm-svn: 373278
2019-10-01 00:29:13 +00:00
Djordje Todorovic ead96d73ac Revert "Reland "[utils] Implement the llvm-locstats tool""
This reverts commit rL372554.

llvm-svn: 372580
2019-09-23 11:04:11 +00:00
Djordje Todorovic 0e490ae0a9 Reland "[utils] Implement the llvm-locstats tool"
The tool reports verbose output for the DWARF debug location coverage.
The llvm-locstats for each variable or formal parameter DIE computes what
percentage from the code section bytes, where it is in scope, it has
location description. The line 0 shows the number (and the percentage) of
DIEs with no location information, but the line 100 shows the number (and
the percentage) of DIEs where there is location information in all code
section bytes (where the variable or parameter is in the scope). The line
50..59 shows the number (and the percentage) of DIEs where the location
information is in between 50 and 59 percentage of its scope covered.

Differential Revision: https://reviews.llvm.org/D66526

llvm-svn: 372554
2019-09-23 07:57:53 +00:00
Djordje Todorovic b21cc626c9 Revert "[utils] Implement the llvm-locstats tool"
This reverts commit rL371520.

llvm-svn: 371527
2019-09-10 14:48:52 +00:00
Djordje Todorovic 54008972d1 [utils] Implement the llvm-locstats tool
The tool reports verbose output for the DWARF debug location coverage.
The llvm-locstats for each variable or formal parameter DIE computes what
percentage from the code section bytes, where it is in scope, it has
location description. The line 0 shows the number (and the percentage) of
DIEs with no location information, but the line 100 shows the number (and
the percentage) of DIEs where there is location information in all code
section bytes (where the variable or parameter is in the scope). The line
50..59 shows the number (and the percentage) of DIEs where the location
information is in between 50 and 59 percentage of its scope covered.

The tool will be very useful for tracking improvements regarding the
"debugging optimized code" support with LLVM ecosystem.

Differential Revision: https://reviews.llvm.org/D66526

llvm-svn: 371520
2019-09-10 13:47:03 +00:00
Martin Storsjo 5d26959039 [Object] Implement relocation resolver for COFF ARM/ARM64
Adding testscases for this via llvm-dwarfdump.

Also add testcases for the existing resolver support for X86.

Differential Revision: https://reviews.llvm.org/D67340

llvm-svn: 371515
2019-09-10 12:31:40 +00:00
Djordje Todorovic c714a88a4d [llvm-dwarfdump] Add additional stats fields
The additional fields will be parsed by the llvm-locstats tool in order to
produce more human readable output of the DWARF debug location quality
generated.

Differential Revision: https://reviews.llvm.org/D66525

llvm-svn: 371506
2019-09-10 10:37:28 +00:00
Djordje Todorovic d409408e31 [test] Update the name of the debug entry values option. NFC
llvm-svn: 371199
2019-09-06 12:23:37 +00:00
Igor Kudrin 991f0fb149 [DWARF] Support DWARF64 in DWARFListTableHeader.
This enables 64-bit DWARF support for parsing range and location list tables.

Differential Revision: https://reviews.llvm.org/D66643

llvm-svn: 371014
2019-09-05 06:49:05 +00:00
Djordje Todorovic 5c6b82a756 [DWARFVerifier] Verify GNU extensions of call site DWARF symbols
Verify that the call site DWARF symbols (added during the implementation
of the debug entry values feature) are generated properly.

Differential Revision: https://reviews.llvm.org/D66865

llvm-svn: 370631
2019-09-02 09:20:46 +00:00
Igor Kudrin 59d5abaa71 [DWARF] Fix reading 64-bit DWARF type units.
The type_offset field is 8 bytes long in DWARF64. The patch extends
TypeOffset to uint64_t and fixes its reading. The patch also fixes
checking of TypeOffset bounds as it was inaccurate in DWARF64 case.

Differential Revision: https://reviews.llvm.org/D66465

llvm-svn: 369378
2019-08-20 12:52:32 +00:00
Igor Kudrin e64af75745 [DWARF] Fix DWARFUnit::getDebugInfoSize() for 64-bit DWARF.
The calculation there was correct only for DWARF32.

Differential Revision: https://reviews.llvm.org/D66421

llvm-svn: 369356
2019-08-20 09:50:44 +00:00
Djordje Todorovic b9973f87c6 Reland "[DwarfDebug] Dump call site debug info"
The build failure found after the rL365467 has been
resolved.

Differential Revision: https://reviews.llvm.org/D60716

llvm-svn: 367446
2019-07-31 16:51:28 +00:00
Jonas Devlieghere 0e7ba06e82 [DWARF] Add more error handling to debug line parser.
This patch exnteds the error handling in the debug line parser to get
rid of the existing MD5 assertion. I want to reuse the debug line parser
from LLVM in LLDB where we cannot crash on invalid input.

Differential revision: https://reviews.llvm.org/D64544

llvm-svn: 366762
2019-07-22 23:23:34 +00:00
Djordje Todorovic 0739ccd3b5 Revert "[DwarfDebug] Dump call site debug info"
A build failure was found on the SystemZ platform.

This reverts commit 9e7e73578e54cd22b3c7af4b54274d743b6607cc.

llvm-svn: 365886
2019-07-12 09:45:12 +00:00
Djordje Todorovic 01eaae6dd1 [DwarfDebug] Dump call site debug info
Dump the DWARF information about call sites and call site parameters into
debug info sections.

The patch also provides an interface for the interpretation of instructions
that could load values of a call site parameters in order to generate DWARF
about the call site parameters.

([13/13] Introduce the debug entry values.)

Co-authored-by: Ananth Sowda <asowda@cisco.com>
Co-authored-by: Nikola Prica <nikola.prica@rt-rk.com>
Co-authored-by: Ivan Baev <ibaev@cisco.com>

Differential Revision: https://reviews.llvm.org/D60716

llvm-svn: 365467
2019-07-09 11:33:56 +00:00
Djordje Todorovic a0d45058eb [DWARF] Handle the DW_OP_entry_value operand
Add the IR and the AsmPrinter parts for handling of the DW_OP_entry_values
DWARF operation.

([11/13] Introduce the debug entry values.)

Co-authored-by: Ananth Sowda <asowda@cisco.com>
Co-authored-by: Nikola Prica <nikola.prica@rt-rk.com>
Co-authored-by: Ivan Baev <ibaev@cisco.com>

Differential Revision: https://reviews.llvm.org/D60866

llvm-svn: 364542
2019-06-27 13:52:34 +00:00
James Henderson 9485b265e8 [binutils] Add response file option to help and docs
Many LLVM-based tools already support response files (i.e. files
containing a list of options, specified with '@'). This change simply
updates the documentation and help text for some of these tools to
include it. I haven't attempted to fix all tools, just a selection that
I am interested in.

I've taken the opportunity to add some tests for --help behaviour, where
they were missing. We could expand these tests, but I don't think that's
within scope of this patch.

This fixes https://bugs.llvm.org/show_bug.cgi?id=42233 and
https://bugs.llvm.org/show_bug.cgi?id=42236.

Reviewed by: grimar, MaskRay, jkorous

Differential Revision: https://reviews.llvm.org/D63597

llvm-svn: 364036
2019-06-21 11:49:20 +00:00
James Henderson beb2493fb7 [llvm-dwarfdump] Remove unnecessary explicit -h behaviour
--help and -h are automatically supported by the command-line parser,
unless overridden by the tool. The behaviour of the PrintHelpMessage
being used for -h prior to this patch is subtly different to that
provided by --help automatically (it omits certain elements of help text
and options, such as --help-list), so overriding the default is not
desirable, without good reason. This patch removes the explicit
specification of -h and its behaviour, so that the default behaviour is
used.

Reviewed by: hintonda

Differential Revision: https://reviews.llvm.org/D63565

llvm-svn: 364029
2019-06-21 11:22:20 +00:00
James Henderson e20326ed33 [test][llvm-dwarfdump] Remove pointless CHECK-NOT lines
The original line was there from when this test was added, but it is
checking for a switch that doesn't exist, so really has no purpose, at
least any more.

llvm-svn: 363833
2019-06-19 16:31:59 +00:00
James Henderson d5f38dae59 [llvm-dwarfdump] Add -o to help text and remove --out-file from doc
-o is in the documentation, but not in the llvm-dwarfdump help text.
This patch adds it by inverting the -o and --out-file aliasing. It also
removes --out-file from the documentation, since we don't really want
people to be using this switch in practice.

Reviewed by: aprantl, JDevlieghere, dblaikie

Differential Revision: https://reviews.llvm.org/D63013

llvm-svn: 363044
2019-06-11 10:20:07 +00:00
Jonas Devlieghere 0da8160df3 [dwarfdump] Add flag to limit the number of parents DIEs
This adds `-parent-recurse-depth` which limits the number of parent DIEs
being dumped.

Differential revision: https://reviews.llvm.org/D62359

llvm-svn: 361671
2019-05-24 21:11:28 +00:00
Caroline Tice abf25745b3 llvm-dwarfdump: Add dwo parsing to --statistics.
Add check for, and parsing of, .dwo files to Statistics.cpp; create a new getNon
SkeletonUnitDie function for DWARFUnit.h

Reviewers: dblaikie

Differential Revision: https://review.llvm.org/D61755

llvm-svn: 360380
2019-05-09 21:53:33 +00:00
Fangrui Song 97b8cd54ad [DWARF] Fix dump of local/foreign TU lists in .debug_names
Differential Revision: https://reviews.llvm.org/D61241

llvm-svn: 359425
2019-04-29 08:55:10 +00:00
Fangrui Song 6a285dfe71 [DWARF] Set discriminator to 0 for DW_LNS_copy
Summary:
Make DW_LNS_copy set the discriminator register to 0, to conform to
DWARF 4 & 5: "Then it sets the discriminator register to 0, and sets the
basic_block, prologue_end and epilogue_begin registers to false."

Because all of DW_LNE_end_sequence, DN_LNS_copy, and special opcodes reset
discriminator to 0, we can move discriminator=0 to appendRowToMatrix.

Also, make DW_LNS_copy print before appending the row, as it is similar
to a address+=0,line+=0 special opcode, which prints before appending
the row.

Reviewers: dblaikie, probinson, aprantl

Reviewed By: dblaikie

Subscribers: danielcdh, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60364

llvm-svn: 358148
2019-04-11 02:02:44 +00:00
Adrian Prantl ce2d45e7ba llvm-dwarfdump: Support alternative architecture names in the -arch filter
<rdar://problem/47918606>

llvm-svn: 357706
2019-04-04 15:48:40 +00:00
Jonas Devlieghere 2156797cf0 [dwarfdump] Remove bogus verifier error
The standard doesn't require a DW_TAG_variable, DW_TAG_formal_parameter
or DW_TAG_constant to A DW_AT_type attribute describing the type of the
variable. It only specifies that it *can* have one.

llvm-svn: 357628
2019-04-03 19:57:13 +00:00
Jonas Devlieghere 4cc567bb9e [DWARFFormValue] Don't consider DW_FORM_data4/8 to be section offsets.
When dumping ToT clan's debug info with dwarfdump, we were seeing an
error saying that that the location list overflows the debug_loc
section. After reducing the testcase we figured out that we were
interpreting the DW_FORM_data4 as a section offset.

In DWARF3 DW_FORM_data4 and DW_FORM_data8 served also as a section
offset. Until now we didn't check check for the DWARF version, because
some producers (read old versions of clang) were still emitting this.
The relevant code/comment was added in 2013, and I believe it's now
reasonable to start checking the version.

The FormValue class is a little bit of a mess because it cashes the
DWARF unit and context when it extracted the value itself. Several
methods of the class rely on it being present, or return an Optional for
the code path that needs it. At the same time the FormValue class also
used in places where there's no DWARF unit.

For this patch I went with the least invasive change: checking the
version from the CU when it's available. If it's not (because the form
value was created from a value directly) we default to the old behavior.

Differential revision: https://reviews.llvm.org/D58698

llvm-svn: 355456
2019-03-05 23:47:22 +00:00
Caroline Tice bcdb1f3d04 llvm-dwarfdump: Add new variable, parameter and inlining statistics; also function source location statistics.
Add statistics for abstract origins, function, variable and parameter
locations; break the 'variable' counts down into variables and
parameters. Also update call site counting to check for
DW_AT_call_{file,line} in addition to DW_TAG_call_site.

Differential revision: https://reviews.llvm.org/D58849

llvm-svn: 355243
2019-03-01 23:51:54 +00:00
Markus Lavin 76dda218a0 [DebugInfo] Prep llvm-dwarfdump for typed DW5 ops.
Adds llvm-dwarfdump support for pretty printing Dwarf5 expressions ops
that reference a base type (right now only DW_OP_convert is added).
Includes verification to verify that the ops operand is actually a
DW_TAG_base_type DIE.

Differential Revision: https://reviews.llvm.org/D58442

llvm-svn: 354552
2019-02-21 08:20:24 +00:00
Caroline Tice cef4c29417 lvm-dwarfdump: Stop counting out-of-line subprogram in the "inlined functions" statistic.
DW_TAG_subprogram DIEs should not be counted in the inlined function statistic. This also addresses the source variables count, as that uses the inlined function count in its calculations.

Differential revision: https://reviews.llvm.org/D57849

llvm-svn: 353491
2019-02-08 00:51:33 +00:00
James Henderson b6b5b1a592 [DebugInfo]Print correct value for special opcode address increment
The wrong variable was being used when printing the address increment in
verbose output of .debug_line. This patch fixes this.

Reviewed by: JDevlieghere

Differential Revision: https://reviews.llvm.org/D57693

llvm-svn: 353288
2019-02-06 10:31:50 +00:00
Wolfgang Pieb 58513b7761 [DWARF v5] Fix DWARF emitter and consumer to produce/expect a uleb for a location description's length.
Reviewer: davide, JDevliegere

Differential Revision: https://reviews.llvm.org/D57550

llvm-svn: 352889
2019-02-01 17:11:58 +00:00
David Blaikie b917c3a41a llvm-dwarfdump: Skip address index info (and dump only the address, if found) when non-verbose dumping addrx forms
There's a few bugs here still - demonstrated with FIXITs in the test.

llvm-svn: 350046
2018-12-24 06:52:31 +00:00
David Blaikie 25179613f6 llvm-dwarfdump: Dump the section name/number for addr attributes
llvm-svn: 350009
2018-12-22 20:34:58 +00:00
David Blaikie ac69af7ad6 llvm-dwarfdump: Improve/fix pretty printing of array dimensions
This is to address post-commit feedback from Paul Robinson on r348954.

The original commit misinterprets count and upper bound as the same thing (I thought I saw GCC producing an upper bound the same as Clang's count, but GCC correctly produces an upper bound that's one less than the count (in C, that is, where arrays are zero indexed)).

I want to preserve the C-like output for the common case, so in the absence of a lower bound the count (or one greater than the upper bound) is rendered between []. In the trickier cases, where a lower bound is specified, a half-open range is used (eg: lower bound 1, count 2 would be "[1, 3)" and an unknown parts use a '?' (eg: "[1, ?)" or "[?, 7)" or "[?, ? + 3)").

Reviewers: aprantl, probinson, JDevlieghere

Differential Revision: https://reviews.llvm.org/D55721

llvm-svn: 349670
2018-12-19 19:34:24 +00:00
George Rimar 1ec49110a7 [llvm-dwarfdump] - Do not error out on R_X86_64_DTPOFF64/R_X86_64_DTPOFF32 relocations.
This is https://bugs.llvm.org/show_bug.cgi?id=39992,

If we have the following code (test.cpp):

thread_local int tdata = 24;
and build an .o file with debug information:

clang --target=x86_64-pc-linux -c bar.cpp -g

Then object produced may have R_X86_64_DTPOFF64/R_X86_64_DTPOFF32 relocations.
(clang emits R_X86_64_DTPOFF64 and gcc emits R_X86_64_DTPOFF32 for the code above for me)

Currently, llvm-dwarfdump fails to compute this TLS relocation when dumping
object and reports an
error:
failed to compute relocation: R_X86_64_DTPOFF64, Invalid data was encountered while parsing the file

This relocation represents the offset in the TLS block and resolved by the linker,
but this info is unavailable at the
point when the object file is dumped by this tool.

The patch adds the simple evaluation for such relocations to avoid emitting errors.
Resulting behavior seems to be equal to GNU dwarfdump.

Differential revision: https://reviews.llvm.org/D55762

llvm-svn: 349476
2018-12-18 12:15:01 +00:00
David Blaikie 023674a9e4 DebugInfo/DWARF: Pretty print subroutine types
Doesn't handle varargs and other fun things, but it's a start. (also
doesn't print these strictly as valid C++ when it's a pointer to
function, it'll print as "void(int)*" instead of "void (*)(int)")

llvm-svn: 348965
2018-12-12 19:53:03 +00:00
David Blaikie 3f8f004daf DebugInfo/DWARF: Improve dumping of pointers to members ('int foo::*' rather than 'int*')
llvm-svn: 348962
2018-12-12 19:34:02 +00:00
David Blaikie 73066d60f1 llvm-dwarfdump: Dump array dimensions in stringified type names
llvm-svn: 348954
2018-12-12 18:46:25 +00:00
George Rimar f8825577be [llvm-dwarfdump] - Simplify the test case.
The test was fully rewritten for simplification.

New test code was suggested by David Blaikie.

Differential revision: https://reviews.llvm.org/D55261

llvm-svn: 348464
2018-12-06 08:42:57 +00:00
George Rimar 7e981f330b [llvm-dwarfdump] - Dump the older versions of .eh_frame/.debug_frame correctly.
The issue is the following.

DWARF 2 used version 1 for .debug_frame.
(Appendix G, p. 416 http://dwarfstd.org/doc/DWARF5.pdf)

lib/MC now always sets version 1 for .eh_frame (and sets 1-4 versions for .debug_frame correctly):
https://github.com/llvm-mirror/llvm/blob/master/lib/MC/MCDwarf.cpp#L1530
https://github.com/llvm-mirror/llvm/blob/master/lib/MC/MCDwarf.cpp#L1562
https://github.com/llvm-mirror/llvm/blob/master/lib/MC/MCDwarf.cpp#L1602

In version 1, return_address_register was defined as ubyte, while other versions
switched to uleb128.
(p 62, http://www.dwarfstd.org/doc/dwarf-2.0.0.pdf)

Patch teaches llvm-dwarfdump about this difference.

Differential revision: https://reviews.llvm.org/D54860

llvm-svn: 348242
2018-12-04 10:01:39 +00:00
George Rimar 6d85c58328 [llvm-dwarfdump] - Stop printing the bogus empty section name on invalid dwarf.
When there is no .debug_addr section for some reason,
llvm-dwarfdump would print the bogus empty section name when dumping ranges
in .debug_info:

DW_AT_ranges [DW_FORM_rnglistx]   (indexed (0x0) rangelist = 0x00000004
    [0x0000000000000000, 0x0000000000000001) ""
    [0x0000000000000000, 0x0000000000000002) "")

That happens because of the code which uses 0 (zero) as a section index as a default value.
The code should use -1ULL instead because technically 0 is a valid zero section index
in ELF and -1ULL is a special constant used that means "no section available".

This is mostly a fix for the overall correctness/safety of the code,
but a test case is provided too.

Differential revision: https://reviews.llvm.org/D55113

llvm-svn: 348115
2018-12-03 10:33:40 +00:00
Luke Cheeseman 6db3a6a4a7 Revert r347490 as it breaks address sanitizer builds
llvm-svn: 347499
2018-11-23 17:13:06 +00:00
Luke Cheeseman d6dbd64104 Revert r343341
- Cannot reproduce the build failure locally and the build logs have
  been deleted.

llvm-svn: 347490
2018-11-23 11:01:47 +00:00
Greg Clayton 44487b655d Add total function byte size and inline function byte size to "llvm-dwarfdump --statistics"
Differential Revision: https://reviews.llvm.org/D54217

llvm-svn: 346531
2018-11-09 18:10:02 +00:00
Wolfgang Pieb 5253cccbd5 [DWARF v5] Verifier: Add checks for DW_FORM_strx* forms.
Adding functionality to the DWARF verifier for DWARF v5 strx* forms which 
index into the string offsets table.

Differential Revision: https://reviews.llvm.org/D54049

llvm-svn: 346061
2018-11-03 00:27:35 +00:00
Saleem Abdulrasool ec77a6517f Revert "Revert "DebugInfo: reduce DIE range verification on object files""
This reverts commit 836c763dadbd9478fa35b1a291a38bf17aa206ba.  Default
initialize the values that MSAN caught.

llvm-svn: 345482
2018-10-28 22:30:48 +00:00
Vlad Tsyrklevich 50d2683a00 Revert "DebugInfo: reduce DIE range verification on object files"
This reverts commits r345441 and r345444, they were causing msan
buildbot failures.

llvm-svn: 345457
2018-10-27 17:39:13 +00:00
Saleem Abdulrasool c8e781c511 test: add missing -triple
Ensure that the test builds for x86_64 as it is an assembly test.  This
should repair the buildbots.

llvm-svn: 345444
2018-10-27 02:27:38 +00:00
Saleem Abdulrasool b342446fe0 DebugInfo: reduce DIE range verification on object files
Relocatable content may have overlapping ranges until the sections are
finalized.  This reduces the amount of verification that is done on an object
file so that invalid errors are not raised.

llvm-svn: 345441
2018-10-27 00:49:33 +00:00
George Rimar 581fc63dc0 [llvm-dwarfdump] - Fix incorrect parsing of the DW_LLE_startx_length
As was already mentioned in comments for D53364, DWARF 5
spec says about DW_LLE_startx_length:

"This is a form of bounded location description that has two unsigned ULEB operands.
The first value is an address index (into the .debug_addr section) that indicates the beginning of the address range
over which the location is valid. The second value is the length of the range. ")

Currently, the length is always parsed as U32.
Patch change the behavior to parse DW_LLE_startx_length as ULEB128 for DWARF 5
and keeps it as U32 for DWARF4+(pre-DWARF5) for compatibility.

Differential revision: https://reviews.llvm.org/D53564

llvm-svn: 345254
2018-10-25 10:56:44 +00:00
Paul Robinson 73766ccfda Make llvm-dwarfdump -name work on type units.
Differential Revision: https://reviews.llvm.org/D53672

llvm-svn: 345203
2018-10-24 21:51:55 +00:00
Jonas Devlieghere 3ef53e10d3 [dwarfdump] Make incompatibility between -diff and -verbose explicit.
Using -diff and -verbose together doesn't work today. We should audit
where these two options interact and fix them. In the meantime we error
out when the user try to specify both.

llvm-svn: 345084
2018-10-23 21:51:44 +00:00
David Blaikie 59ac206433 llvm-dwarfdump: Support RLE_addressx and RLE_startx_length in .debug_rnglists
llvm-svn: 344835
2018-10-20 06:16:25 +00:00
Adrian Prantl 8aa69e9927 llvm-dwarfdump: Extend --name to also search DW_AT_linkage_name.
rdar://problem/45132695

llvm-svn: 344079
2018-10-09 20:51:33 +00:00
Wolfgang Pieb a9ea9c5034 [DWARF] Make llvm-dwarfdump display the .debug_loc.dwo section. Fixes PR38991.
Reviewer: dblaikie

Differential Revision: https://reviews.llvm.org/D52444

llvm-svn: 344068
2018-10-09 18:38:55 +00:00
Vedant Kumar 5931b4e5b5 [DebugInfo] Add support for DWARF5 call site-related attributes
DWARF v5 introduces DW_AT_call_all_calls, a subprogram attribute which
indicates that all calls (both regular and tail) within the subprogram
have call site entries. The information within these call site entries
can be used by a debugger to populate backtraces with synthetic tail
call frames.

Tail calling frames go missing in backtraces because the frame of the
caller is reused by the callee. Call site entries allow a debugger to
reconstruct a sequence of (tail) calls which led from one function to
another. This improves backtrace quality. There are limitations: tail
recursion isn't handled, variables within synthetic frames may not
survive to be inspected, etc. This approach is not novel, see:

  https://gcc.gnu.org/wiki/summit2010?action=AttachFile&do=get&target=jelinek.pdf

This patch adds an IR-level flag (DIFlagAllCallsDescribed) which lowers
to DW_AT_call_all_calls. It adds the minimal amount of DWARF generation
support needed to emit standards-compliant call site entries. For easier
deployment, when the debugger tuning is LLDB, the DWARF requirement is
adjusted to v4.

Testing: Apart from check-{llvm, clang}, I built a stage2 RelWithDebInfo
clang binary. Its dSYM passed verification and grew by 1.4% compared to
the baseline. 151,879 call site entries were added.

rdar://42001377

Differential Revision: https://reviews.llvm.org/D49887

llvm-svn: 343883
2018-10-05 20:37:17 +00:00
Adrian Prantl 7875142b5c Format the dwarfdump --statistics version as an integer instead of a string.
llvm-svn: 343864
2018-10-05 17:41:30 +00:00
Luke Cheeseman 10981cc884 Revert r343317
- asan buildbots are breaking and I need to investigate the issue

llvm-svn: 343341
2018-09-28 17:01:50 +00:00
Luke Cheeseman 21f2955bb2 Reapply changes reverted by r343235
- Add fix so that all code paths that create DWARFContext
  with an ObjectFile initialise the target architecture in the context
- Add an assert that the Arch is known in the Dwarf CallFrameString method

llvm-svn: 343317
2018-09-28 13:37:27 +00:00
Adrian Prantl 2e102480ac llvm-dwarfdump --statistics: Unique abstract origins across multiple CUs.
Instead of indexing local variables by DIE offset, use the variable
name + the path through the lexical block tree. This makes the lookup
key consistent across duplicate abstract origins in different CUs.

llvm-svn: 342776
2018-09-21 21:59:34 +00:00
Jonas Devlieghere b32274242d [dwarfdump] Verify DW_AT_type is set and points to a compatible DIE.
This extends the verifier to catch three new errors:

  * Missing DW_AT_type attributes for DW_TAG_formal_parameter,
    DW_TAG_variable and DW_TAG_array_type.

  * Valid references for DW_AT_type pointing to a non-type tag.

Differential revision: https://reviews.llvm.org/D52223

llvm-svn: 342713
2018-09-21 07:50:21 +00:00
Jonas Devlieghere 7ef2c2021e [dwarfdump] Verify compatibility of attribute TAGs.
Verify that DW_AT_specification and DW_AT_abstract_origin reference a
DIE with a compatible tag.

Differential revision: https://reviews.llvm.org/D38719

llvm-svn: 342712
2018-09-21 07:49:29 +00:00
Jonas Devlieghere 881452384a [dwarfdump] Improve -diff option by hiding more data.
The -diff option makes it easy to diff dwarf by hiding addresses and
offsets. However not all of them were hidden, which should be fixed by
this patch.

Differential revision: https://reviews.llvm.org/D51593

llvm-svn: 341377
2018-09-04 16:21:37 +00:00
Jonas Devlieghere 6e5c7e6037 [DebugInfo] Have the verifier accept missing linkage names.
According to the standard, for the .debug_names (the "dwarf accelerator
tables"):

> If a subprogram or inlined subroutine is included, and has a
> DW_AT_linkage_name attribute, there will be an additional index entry
> for the linkage name.

For Swift we generate DW_structure_types with a linkage name and the
verifier was incorrectly rejecting this. This patch fixes that by only
considering the linkage name in those particular cases. The test is the
"reduced" debug info of the failing swift test on swift.org.

Differential revision: https://reviews.llvm.org/D51420

llvm-svn: 341311
2018-09-03 12:12:17 +00:00
Victor Leschuk 58d3399d8a [DWARF] Support for .debug_addr (consumer)
This patch implements basic support for parsing
  and dumping DWARFv5 .debug_addr section.

llvm-svn: 338447
2018-07-31 22:19:19 +00:00
Wolfgang Pieb 439801ba1d [DWARF v5] Refactor range lists dumping by using a more generic way of handling tables of lists.
The intent is to use it for location list tables as well. Change is almost NFC with the exception
of the spelling of some strings used during dumping (all lowercase now).

Reviewer: JDevlieghere

Differential Revision: https://reviews.llvm.org/D49500

llvm-svn: 337763
2018-07-23 22:37:17 +00:00
Gabor Buella da4a966e1c NFC - Various typo fixes in tests
llvm-svn: 336268
2018-07-04 13:28:39 +00:00
Pavel Labath 4adc88ed25 [DWARF/AccelTable] Remove getDIESectionOffset for DWARF v5 entries
Summary:
This method was not correct for entries in DWO files as it assumed it
could just add up the CU and DIE offsets to get the absolute DIE offset.
This is not correct for the DWO files, as here the CU offset will
reference the skeleton unit, whereas the DIE offset will be the offset
in the full unit in the DWO file.

Unfortunately, this means that we are not able to determine the absolute
DIE offset using the information in the .debug_names section alone,
which means we have to offload some of this work to the users of this
class.

To demonstrate how this can be done, I've added/fixed the ability to
lookup entries using accelerator tables in DWO files in llvm-dwarfdump.
To make this happen, I've needed to make two extra changes in other
classes:
- made the DWARFContext method to lookup a CU based on the section
  offset public. I've needed this functionality to lookup a CU, and this
  seems like a useful thing in general.
- made DWARFUnit::getDWOId call extractDIEsIfNeeded. Before this, the
  DWOId was filled in only if the root DIE happened to be parsed
  before we called the accessor. Since the lazy parsing is supposed to
  happen under the hood, calling extractDIEsIfNeeded seems appropriate.

Reviewers: JDevlieghere, aprantl, dblaikie

Subscribers: mgrang, llvm-commits

Differential Revision: https://reviews.llvm.org/D48009

llvm-svn: 334578
2018-06-13 08:14:27 +00:00
Pavel Labath 59870af66f DWARFAcceleratorTable: fix equal_range iterators
Summary:
Both (Apple and DWARF5) implementations of the iterators had bugs which
resulted in crashes if one attempted to iterate through the accelerator
tables all the way.

For the Apple tables, the issue was that we did not clear the DataOffset
field when we reached the end, which made our iterator compare unequal
to the "end" iterator. For the Dwarf5 tables, the problem was that we
incremented the CurrentIndex pointer and then used the incremented
(possibly invalid) pointer to check whether we have reached the end of
the index list.

The reason these bugs went undetected is because their only user
(dwarfdump) only ever searched for the first match. Besides allowing us
to test this fix, changing llvm-dwarfdump --find to display all matches
seems like a good improvement (it makes the behavior consistent with the
--name option), so I change llvm-dwarfdump to do that.

The existing tests would be sufficient to test this fix with the new
llvm-dwarfdump behavior, but I add a special test that demonstrates that
the tool indeed displays multiple results. The find.test test needed to
be tweaked a bit as the tool now does not print the ".debug_info
contents" header (also consistent with how --name works).

Reviewers: JDevlieghere, aprantl, dblaikie

Subscribers: mgrang, llvm-commits

Differential Revision: https://reviews.llvm.org/D47543

llvm-svn: 333635
2018-05-31 08:47:00 +00:00
Jonas Devlieghere cb547cbb5c [dwarfdump] Make -c and -p work together
When requesting to dump both the parent chain and children, we used to
print the DIE more than once because we propagated the dump options to
the parent without clearing the respective flags. This commit fixes this
oversight and adds a test.

rdar://39415292

Differential revision: https://reviews.llvm.org/D47263

llvm-svn: 333350
2018-05-26 19:39:56 +00:00
Jonas Devlieghere 27126f5260 [Support] Add color cl category.
This commit adds a color category so tools can document this option and
enables it for dwarfdump and dsymuttil.

rdar://problem/40498996

llvm-svn: 333176
2018-05-24 11:36:57 +00:00
Pavel Labath 80827f10a1 Reapply "DWARFVerifier: Check "completeness" of .debug_names section"
This is a resubmit of r331868 (D46583), which was reverted due to
failures on the PS4 bot.

These have been resolved with r332246/D46748.

llvm-svn: 332349
2018-05-15 13:24:10 +00:00
James Henderson a3acf99e59 [DWARF] Rework debug line parsing to use llvm::Error and callbacks
Reviewed by: dblaikie, JDevlieghere, espindola

Differential Revision: https://reviews.llvm.org/D44560

Summary:
The .debug_line parser previously reported errors by printing to stderr and
return false. This is not particularly helpful for clients of the library code,
as it prevents them from handling the errors in a manner based on the calling
context. This change switches to using llvm::Error and callbacks to indicate
what problems were detected during parsing, and has updated clients to handle
the errors in a location-specific manner. In general, this means that they
continue to do the same thing to external users. Below, I have outlined what
the known behaviour changes are, relating to this change.

There are two levels of "errors" in the new error mechanism, to broadly
distinguish between different fail states of the parser, since not every
failure will prevent parsing of the unit, or of subsequent unit. Malformed
table errors that prevent reading the remainder of the table (reported by
returning them) and other minor issues representing problems with parsing that
do not prevent attempting to continue reading the table (reported by calling a
specified callback funciton). The only example of this currently is when the
last sequence of a unit is unterminated. However, I think it would be good to
change the handling of unrecognised opcodes to report as minor issues as well,
rather than just printing to the stream if --verbose is used (this would be a
subsequent change however).

I have substantially extended the DwarfGenerator to be able to handle
custom-crafted .debug_line sections, allowing for comprehensive unit-testing
of the parser code. For now, I am just adding unit tests to cover the basic
error reporting, and positive cases, and do not currently intend to test every
part of the parser, although the framework should be sufficient to do so at a
later point.

Known behaviour changes:
  - The dump function in DWARFContext now does not attempt to read subsequent
  tables when searching for a specific offset, if the unit length field of a
  table before the specified offset is a reserved value.
  - getOrParseLineTable now returns a useful Error if an invalid offset is
  encountered, rather than simply a nullptr.
  - The parse functions no longer use `WithColor::warning` directly to report
  errors, allowing LLD to call its own warning function.
  - The existing parse error messages have been updated to not specifically
  include "warning" in their message, allowing consumers to determine what
  severity the problem is.
  - If the line table version field appears to have a value less than 2, an
  informative error is returned, instead of just false.
  - If the line table unit length field uses a reserved value, an informative
  error is returned, instead of just false.
  - Dumping of .debug_line.dwo sections is now implemented the same as regular
  .debug_line sections.
  - Verbose dumping of .debug_line[.dwo] sections now prints the prologue, if
  there is a prologue error, just like non-verbose dumping.

As a helper for the generator code, I have re-added emitInt64 to the
AsmPrinter code. This previously existed, but was removed way back in r100296,
presumably because it was dead at the time.

This change also requires a change to LLD, which will be committed separately.

llvm-svn: 331971
2018-05-10 10:51:33 +00:00
Pavel Labath e0207a60dd Revert "DWARFVerifier: Check "completeness" of .debug_names section"
The new verifier check has found an error in the
debug-names-name-collisions.ll test on the PS4 bot:

error: Name Index @ 0x0: Entry @ 0xdc: mismatched Name of DIE @ 0x23: index - _ZN3foo3fooE; debug_info - foo.

Reverting while I investigate whether this is a bug in the verifier or
the generator.

This reverts commit r331868.

llvm-svn: 331869
2018-05-09 12:26:19 +00:00
Pavel Labath 3280e0467f DWARFVerifier: Check "completeness" of .debug_names section
Summary:
This patch implements a check which makes sure all entries required by
the DWARF v5 specification are present in the Name Index. The algorithm
tries to follow the wording of Section 6.1.1.1 of the spec as closely as
possible.

The main deviation from it is that instead of a whitelist-based approach
in the spec "The name index must contain an entry for each debugging
information entry that defines a named subprogram, label, variable,
type, or namespace" I chose a blacklist-based one, where I consider
everything to be "in" and then remove the entries that don't make sense.
I did this because it has more potential for catching interesting cases
and the above is a bit vague (it uses plain words like "variable" and
"subprogram", but the rest of the section speaks about specific TAGs).

This approach has raised some interesting questions, the main one being
whether enumerator values should be indexed. The consensus seems to be
that they should, although it does not follow from section 6.1.1.1.
For the time being I made the verifier ignore these, as LLVM does not do
this yet, and I wanted to get a clean run when verifying generated debug
info.

Another interesting case was the DW_TAG_imported_declaration. It was not
immediately clear to me whether this should go in or not, but currently
it is not indexed, and (unlike the enumerators) in does not seem to cause
problems for LLDB, so I've also ignored it.

Reviewers: JDevlieghere, aprantl, dblaikie

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D46583

llvm-svn: 331868
2018-05-09 12:06:17 +00:00
Shiva Chen 2c864551df [DebugInfo] Add DILabel metadata and intrinsic llvm.dbg.label.
In order to set breakpoints on labels and list source code around
labels, we need collect debug information for labels, i.e., label
name, the function label belong, line number in the file, and the
address label located. In order to keep these information in LLVM
IR and to allow backend to generate debug information correctly.
We create a new kind of metadata for labels, DILabel. The format
of DILabel is

!DILabel(scope: !1, name: "foo", file: !2, line: 3)

We hope to keep debug information as much as possible even the
code is optimized. So, we create a new kind of intrinsic for label
metadata to avoid the metadata is eliminated with basic block.
The intrinsic will keep existing if we keep it from optimized out.
The format of the intrinsic is

llvm.dbg.label(metadata !1)

It has only one argument, that is the DILabel metadata. The
intrinsic will follow the label immediately. Backend could get the
label metadata through the intrinsic's parameter.

We also create DIBuilder API for labels to be used by Frontend.
Frontend could use createLabel() to allocate DILabel objects, and use
insertLabel() to insert llvm.dbg.label intrinsic in LLVM IR.

Differential Revision: https://reviews.llvm.org/D45024

Patch by Hsiangkai Wang.

llvm-svn: 331841
2018-05-09 02:40:45 +00:00
Jonas Devlieghere 4bbcb5ab04 [DebugInfo] Prevent infinite recursion for malformed DWARF
This prevents infinite recursion in DWARFDie::findRecursively for
malformed DWARF where a DIE references itself.

This fixes PR36257.

Differential revision: https://reviews.llvm.org/D43092

llvm-svn: 331200
2018-04-30 17:02:41 +00:00
Pavel Labath 54d736c416 [test] Avoid spurious failure in debug-names-find.s. NFC.
Have llvm-dwarfdump take input from stdin to avoid leaking the host paths into
the tests, causing nondeterministic failures.

llvm-svn: 330121
2018-04-16 11:16:41 +00:00
Pavel Labath c9f07b06a1 DWARFVerifier: validate information in name index entries
Summary:
This patch add checks to verify that the information in the name index
entries is consistent with the debug_info section. Specifically, we
check that entries point to valid DIEs, and their names, tags, and
compile units match the information in the debug_info sections.

These checks are only run if the previous checks did not find any errors
in the name index headers. Attempting to proceed with the checks anyway
would likely produce a lot of spurious errors and the verification code
would need to be very careful to avoid crashing.

I also add a couple of more checks to the abbreviation-validation code
to verify that some attributes are always present (an index without a
DW_IDX_die_offset attribute is fairly useless).

The entry verification works only on indexes without any type units - I
haven't attempted to extend it to type units, as we don't even have a
DWARF v5-compatible type unit generator at the moment.

Reviewers: JDevlieghere, aprantl, dblaikie

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45323

llvm-svn: 329392
2018-04-06 13:34:12 +00:00
Pavel Labath 54ca2d688a [debug_loc] Fix typo in DWARFExpression constructor
Summary:
The positions of the DwarfVersion and AddressSize arguments were
reversed, which caused parsing for dwarf opcodes which contained
address-size-dependent operands (such as DW_OP_addr). Amusingly enough,
none of the address-size asserts fired, as dwarf version was always 4,
which is a valid address size.

I ran into this when constructing weird inputs for the DWARF verifier. I
I add a test case as hand-written dwarf -- I am not sure how to trigger
this differently, as having a DW_OP_addr inside a location list is a
fairly non-standard thing to do.

Fixing this error exposed a bug in the debug_loc.dwo parser, which was
always being constructed with an address size of 0. I fix that as well
by following the pattern in the non-dwo parser of picking up the address
size from the first compile unit (which is technically not correct, but
probably good enough in practice).

Reviewers: JDevlieghere, aprantl, dblaikie

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45324

llvm-svn: 329381
2018-04-06 08:49:57 +00:00
Pavel Labath ea0f841c3b .debug_names: Correctly align the AugmentationStringSize field
We should align the value of the field, not the overall section offset.

This distinction matters if one of the debug_names contributions is not
of size which is a multiple of four. The dwarf producers may choose to
emit rounded contributions, but they are not required to do so. In the
latter case, without this patch we would corrupt the parsing state, as
we would adjust the offset even if subsequent contributions contained
correctly rounded augmentation strings.

llvm-svn: 328796
2018-03-29 15:12:45 +00:00
Pavel Labath 2d1fc4375f .debug_names: Parse DW_IDX_die_offset as a reference
Before this patch we were parsing the attributes as section offsets, as
that is what apple_names is doing. However, this is not correct as DWARF
v5 specifies that this attribute should use the Reference form class.

This also updates all the testcases (except the ones that deliberately
pass a different form) to use the correct form class.

llvm-svn: 328773
2018-03-29 13:47:57 +00:00
Wolfgang Pieb ab068eaa57 [DWARF][DWARF v5]: Adding support for dumping DW_RLE_offset_pair and DW_RLE_base_address
Reviewers: dblakie, aprantl

Differential Revision: https://reviews.llvm.org/D44811

llvm-svn: 328662
2018-03-27 20:27:36 +00:00
Pavel Labath 79cd942c23 DWARFVerifier: verify debug_names abbreviation table
Summary:
This commit adds checks of the abbreviation table in a DWARF v5 Name
Index. The most interesting/useful check is the one which checks that
each index attributes is encoded using the correct form class, but it
also checks for the more obvious errors like unknown
forms/tags/attributes and duplicated attributes.

Reviewers: JDevlieghere, aprantl, dblaikie

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D44736

llvm-svn: 328202
2018-03-22 14:50:44 +00:00
Pavel Labath 906b777a6a DWARFVerifier: Enhance validation of .debug_names hash tables
Summary:
This patch adds more checks to the .debug_names validator. Specifically,
they check for:
- buckets claiming to be non-empty but pointing to mismatched hashes
  (most consumers would interpret this as an empty bucket, but it
  questionable whether the generator meant that)
- hashes that are not reachable from any bucket
- names with incorrect hashes

Together, these checks ensure that any name in the index can be reached
through the hash table using the regular lookup algorithm. We also warn
if we encounter a name index without a hash table.

Reviewers: JDevlieghere, aprantl, dblaikie

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D44433

llvm-svn: 327699
2018-03-16 10:02:16 +00:00
Pavel Labath 47c3472c41 [DebugInfo/AccelTable] Fix inconsistency in getDIEOffset implementations
Summary:
Even though the getDIEOffset offset function was common for the two
accelerator table implementations, it was doing two different things:
for the Apple tables, it was returning the die offset relative to the
start of the section, whereas for DWARF v5 tables, it was relative to
the start of the CU.

I resolve this by renaming the function to getDIESectionOffset to make
it obvious what the function returns, and change the DWARF
implementation to return the section offset. I also keep the CU-relative
accessor, but only in the DWARF implementation (there is no way to get
this information for the Apple tables). This was not caught by existing
tests because the hand-written inputs also erroneously used section
offsets instead of CU-relative ones.

While looking at this, I noticed that the Apple implementation was not
fully correct either -- the header contains a DIEOffsetBase field, which
should be added to offsets encoded with the DW_FORM_ref*** family, but
this was not being used. This went unnoticed because all current writers
set this field to zero anyway. I fix this as well and add a hand-written
test which demonstrates the issue.

Reviewers: JDevlieghere, dblaikie

Subscribers: aprantl, llvm-commits

Differential Revision: https://reviews.llvm.org/D44202

llvm-svn: 327116
2018-03-09 11:58:59 +00:00