Fifth of 5 small patches to fix various breakpad issues found
while testing dump_syms of DWARF v5 in ChromeOS.
DWARF v5 introduces a new dwp version, version 5. The current
dwp reader only recognizes versions 1 & 2 as valid dwp versions. This
CL fixes that.
Change-Id: I5ac43b318b59e406ca1f6749232709aaef59a67b
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/2634550
Reviewed-by: Sterling Augustine <saugustine@google.com>
Fourth of 5 small patches to fix various breakpad issues found
while testing dump_syms on DWARF v5 in ChromeOS.
Dwarfv5 adds many new Type Unit sections to debug information. Since
these only contain type information, they are of no interest to
dump_syms. This CL gets dump_syms to skip trying to process the
type unit sections. Without this CL, dump_syms takes ~ 3 hours to
process the DWARF v5 Chrome binary. With this CL, dump_syms takes
~ 8 minutes to process the DWARF v5 Chrome binary (about the same
time as it takes for DWARF v4).
This CL also adds a test case to verify that type units are being
skipped.
Change-Id: Ie0bb2d675718f7041b8e9b3186ed44f80a3ad39c
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/2634549
Reviewed-by: Sterling Augustine <saugustine@google.com>
Second of 5 small patches to fix various breakpad issues found
while testing dump_syms on DWARF v5 in ChromeOS.
This patch adds code to properly find & parse the
DW_AT_str_offsets_base attribute, and use it to handle strings
of the forms DW_FORM_strx, DW_FORM_strx1..DW_FORM_strx4 This is the
largest of the DWARF5 fixes. It also includes a unittest to test
using a string offset.
Change-Id: I5d1def862d9d91cae4b2853578441e04ea85449d
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/2634547
Reviewed-by: Sterling Augustine <saugustine@google.com>
First of 5 small patches to fix various breakpad issues found
while testing dump_syms on DWARF v5 in ChromeOS.
This patch adds some missing DWARF enums, and their uses, and fixes
one small typo (was updating 'lineptr' instead of '*lineptr').
Change-Id: Ic674d5db29f29a69a3f6e370d0553eb4139c91de
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/2634546
Reviewed-by: Sterling Augustine <saugustine@google.com>
Most of this is simple, "Read the form, get the data, then
call ProcessAttribute."
Handling DW_FORM_implcit_const is a little trickier, as it
is the only form that stores its value inline in the abbrev
table itself. Add a test for that.
Print errors for supplementary object files.
Change-Id: I0999b039848bded1891998a866e5059acd538a09
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/2446627
Reviewed-by: Joshua Peraza <jperaza@chromium.org>
This is a big change. dwarf5 range lists are quite a bit more complicated
than dwarf 4 range lists, both in the contextual information required, and
in their own representation and interpretation.
The big design choice here is how to pass the CU information all the
way down to the reader. I chose a structure, because otherwise the
parameter list gets very long and error prone (and has to be passed
down several levels). This structure could be made a parto of the CU
context itself, or the range handler, so it wouldn't have to be
separately assembled at range-list read time, but both of those
solutions get even more invasive, and harder to follow.
I've tried to figure out how to break this into smaller changes, but it
affects nearly everything that has to do with a compilation unit's
own addresses and when decisions must be made about how to read them.
Dependency injection will do that to you.
It does add tests for range list reading, which did not exist before.
Change-Id: I923b9a2c3379a0f52609bc05310097de5cbb7227
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/2446635
Reviewed-by: Joshua Peraza <jperaza@chromium.org>
This reverts commit 2b936b06c1.
After getting deep into the dwarf5 range reader, I realized that this
should be done a somewhat different way. So reverting in favor or
a better design, coming in a few minutes.
Change-Id: Ie0b2846e70b3df1e637831e96ea69fe093f4e712
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/2446011
Reviewed-by: Mark Mentovai <mark@chromium.org>
Dwarf5 introduces a new .debug_rngslist section, to take the place
of the Dwarf4 .debug_ranges. However, the dwarf version is CU-based,
and not file-based, so there can be both sections, and which section
the CU needs isn't known until the dwarf parser encounters either
DW_AT_ranges (dwarf 4 and lower) or DW_AT_rnglists_base (dwarf 5).
This change refactors the code around range lists and range list
readers to defer the decision of what section to parse until
the relevant attribute is found. It moves the range list section
reader from the range-list handler itself (which doesn't know which
section it will use) to the CU context, and then lets the handler
know when it encounters DW_AT_ranges.
I will add a reader for the new dwarf5 section, along with the code to
interpret the new section, and its forms and such in a subsequent patch.
Change-Id: Ie92e4c9daa3f0acb98d7ef74f6b9c2065db849b1
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/2433684
Reviewed-by: Mark Mentovai <mark@chromium.org>
We do this in a lot of places, but we're inconsistent.
Normalize the code to the Google C++ style guide.
Change-Id: Ic2aceab661ce8f6b993dda21b1cdf5d2198dcbbf
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/2262932
Reviewed-by: Sterling Augustine <saugustine@google.com>
Reviewed-by: Mark Mentovai <mark@chromium.org>
For the upcoming Dwarf5 LineInfo changes, we will need to get
several additional sections by name, but without a the Compilation
Unit. This change prepares for that.
Change-Id: I566855abb339a856110a2f7d243d3848fe2b3c18
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/2268861
Reviewed-by: Mark Mentovai <mark@chromium.org>
Given the almost nonexistent direct dwarfreader tests, I think
the best way to test these dwarf5 additions will be to add a full
dwarf5 compilation unit similar to the ones used incidentally in
the other tests. But I can't do that until enough dwarf5 is
correctly implemented.
Change-Id: I3418bda7212ae85c4b67232a2ab8fea9b9ca5d42
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/2258838
Reviewed-by: Mark Mentovai <mark@chromium.org>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Adding the new forms by type and processing should avoid
the problems with 0c0e24f709,
where new forms weren't handled in switch statements, breaking
the build.
Testing this should follow the testing for DW_FORM_GNU_str_index,
very closely, but there doesn't appear to be any tests for that,
or even DW_FORM_strp.
Change-Id: I609d56b1dc879971bfef1070f063f8457fec6017
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/2233839
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Mark Mentovai <mark@chromium.org>
This reverts commit dbd454dbe4.
Reason for revert: The parent CL is causing breakage on CrOS due to
unhandled enums. Before we can revert that, we need to revert this.
Bug: google-breakpad:812
Change-Id: I7c2446f3cd8ed9f6411e90dbdd2434bc463b2f6c
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/2095798
Reviewed-by: Mark Mentovai <mark@chromium.org>
This enables the DWARF reader to properly parse DW_AT_ranges attributes
in compilation units and functions. Code covered by a function is now
represented by a vector of ranges instead of a single contiguous range
and DW_AT_ranges entries are used to populate it. All the code and tests
that assumed functions to be contiguous entities has been updated to
reflect the change. DW_AT_ranges attributes found in compilation units
are parsed but no data is generated for them as it is not currently needed.
BUG=754
Change-Id: I310391b525aaba0dd329f1e3187486f2e0c6d442
Reviewed-on: https://chromium-review.googlesource.com/1124721
Reviewed-by: Ted Mielczarek <ted.mielczarek@gmail.com>
This silences a warning in newer versions of clang that complains
about "register" being a deprecated keyword.
Bug: chromium:780692
Change-Id: If354b9b18421e3e910849b385c44207e0ce02590
Reviewed-on: https://chromium-review.googlesource.com/750362
Reviewed-by: Mark Mentovai <mark@chromium.org>
Breakpad’s DWARF line table reader only understood line tables at the
level of DWARF 2. This wasn’t a problem because LLVM only produced line
tables at this level, even when generating DWARF 4. But LLVM would like
to output DWARF 4 line tables when generating DWARF 4, and Breakpad
needs to understand this format. (Meanwhile, it seems that GCC has used
DWARF 4 line tables with DWARF 4 output since 4.5.0, 2010-04-14.)
DWARF 3 line tables are fully compatible with DWARF 2 (assuming that
nothing needs “prologue end,” “epilogue begin,” or “isa”, and opcodes
related to these fields are properly skipped). DWARF 4 changes the line
number program header slightly to include a “maximum operations per
instruction” field. This field must be recognized, but can safely be
ignored (and assumed to be always 1) if VLIW architectures are not
supported (they aren’t). DWARF 4 also introduces a “discriminator”,
whose opcode can also be skipped if these values are not needed (they
shouldn’t be).
This recognizes the “maximum operations per instruction” field when
processing DWARF 4 line tables, but asserts that its value is 1 and
otherwise ignores it.
This is not compatible with VLIW architectures that set this field to a
value other than 1. Such architectures are irrelevant to Breakpad, and
mainline GCC and the proposed LLVM patch always set this field to 1.
There are other things that could be extracted from DWARF 3 and 4 line
tables that aren’t currently extracted (although these are currently
irrelevant to Breakpad too).
Bug: google-breakpad:745
Change-Id: I5bf9c0b1aa654849c9cce64e60682447d10be8ba
Reviewed-on: https://chromium-review.googlesource.com/663441
Reviewed-by: Mike Frysinger <vapier@chromium.org>
CIE looks like it's been emitted by clang since ~May 2015 [1]. This
means that we didn't have any CFI because this parse aborted, which
meant that all stack walks reverted to stack scanning. Allow expected
values for address size and segment descriptor size through so that
dump_syms can generate at least somewhat reasonable data.
[1]: http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20150518/277292.htmlR=mark@chromium.org
BUG=chromium:627529
Change-Id: I6dc92f51c4afd25c2adff92c09ccb8bb03bf9112
Reviewed-on: https://chromium-review.googlesource.com/406012
Reviewed-by: Mark Mentovai <mark@chromium.org>
This added debug fission support.
It tries to find the dwp file from the debug dir /usr/lib/debug/*/debug
and read symbols from them.
Most of this patch comes from
https://critique.corp.google.com/#review/52048295
and some fixes after that.
The elf_reader.cc comes from TOT google code. I just
removed some google dependency.
Current problems from this patch
1: Some type mismatch: from uint8_t * to char *.
2: Some hack to find the .dwp file. (replace .debug with .dwp)
BUG=chromium:604440
R=dehao@google.com, ivanpe@chromium.org
Review URL: https://codereview.chromium.org/1884283002 .
Newer gcc versions default to -Werror=narrowing when using newer C++
standards (which we do). This causes issues when we try to stuff a
value like 0xea into a char -- the value is out of range for signed
char bytes. That's when gcc throws an error:
.../bytereader_unittest.cc: In member function 'virtual void Reader_DW_EH_PE_absptr4_Test::TestBody()':
.../bytereader_unittest.cc:400:55: error: narrowing conversion of '234' from 'int' to 'char' inside { } [-Wnarrowing]
BUG=chromium:579384
TEST=`make check` passes
R=mark@chromium.org
Review URL: https://codereview.chromium.org/1605153004 .
Previously, dump_syms did not handle DW_FORM_ref_addr if it appeared
in DWARF 4 debugging info.
Also fix a DW_FORM_ref_addr case so that it doesn't fall through to
the next switch case when assertions are disabled and the DWARF
version isn't recognised.
The following steps will reproduce the problem when using LLVM 3.4:
cat <<END >example1.c
int main() { return 0; }
END
cat <<END >example2.c
void foo(int x) {}
END
clang -emit-llvm -g -c example1.c -o example1.bc
clang -emit-llvm -g -c example2.c -o example2.bc
llvm-link-3.4 example1.bc example2.bc -o combined.bc
clang combined.bc -o executable
./google-breakpad/build/src/tools/linux/dump_syms/dump_syms executable
When using LLVM bitcode linking in this way, LLVM's backend generates
partially-merged DWARF debugging info in which some of the references
to the "int" type go via "DW_FORM_ref_addr". Since PNaCl uses LLVM
bitcode linking, this dump_syms failure occurs with nexes produced by
the PNaCl toolchain.
BUG= https://code.google.com/p/chromium/issues/detail?id=416368
TEST= see above
R=mark@chromium.org, mcgrathr@chromium.org
Review URL: https://breakpad.appspot.com/5744002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1408 4c0a9323-5329-0410-9bdc-e9ce6186880e
This patch allows Breakpad's DWARF reader to at least read or skip
attributes using the new forms defined in version 4 of the DWARF
specification, instead of crashing.
Attributes encoded using DW_FORM_flag_present, DW_FORM_sec_offset, and
DW_FORM_exprloc should work fine now. However, compilation units using
DW_FORM_ref_sig8 to refer to types in .debug_types will need further work
to support. (GCC 4.6.2 does not emit .debug_types sections.)
Specifically:
- dwarf2reader::DwarfForm gets new values.
- dwarf2reader::Dwarf2Handler and dwarf2reader::DIEHandler get new handler
methods, named ProcessAttributeSignature, for DW_FORM_ref_sig8 attributes.
- dwarf2reader::CompilationUnit reads DW_FORM_ref_sig8 attributes, and
passes them to ProcessAttributeSignature. It also gets support for
DW_FORM_sec_offset, DW_FORM_exprloc, and DW_FORM_flag_present, using the
existing appropriate ProcessAttribute* methods.
- dwarf2reader::DIEDispatcher passes through ProcessAttributeSignature
attributes to its DIEHandler.
- Unit tests are updated.
a=jimb, r=ted.mielczarek
Review URL: http://breakpad.appspot.com/343003/
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@912 4c0a9323-5329-0410-9bdc-e9ce6186880e
forbidden by the style guide, and are bad practice in headers even under
style rules that tolerate this construct.
This fixes warnings such as:
In file included from dwarf2reader.cc:34:
dwarf2reader.h:53:17: warning: using namespace directive in global context in header [-Wheader-hygiene]
Review URL: http://breakpad.appspot.com/312002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@862 4c0a9323-5329-0410-9bdc-e9ce6186880e
After the final DIE in a compilation unit, there may be any number of
zero bytes present. This is meant to allow producers to align
compilation unit starting points when necessary.
This patch changes the dwarf2reader::CompilationUnit class to skip
those zero bytes, rather than interpreting them as 'end of children'
markers for DIEs that do not exist. Without this change, the padding
bytes will cause the reader to attempt to pop an offset from an empty
stack, and call EndDIE with a garbage offset.
a=jimblandy, r=mmentovai
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@667 4c0a9323-5329-0410-9bdc-e9ce6186880e
Perhaps there once was some reason one needed the DIE offset stack to
have an unusual lifetime, but there is none now.
a=jimblandy, r=mmentovai
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@666 4c0a9323-5329-0410-9bdc-e9ce6186880e
This patch avoids unnecessary use of the <cfoo> headers in files that don't
actually use the identifiers they declare in the std:: namespace.
It also changes some files to better conform with the "Names and Order of
Includes" rules in the Google C++ Style Guide.
A=jimb R=mark
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@619 4c0a9323-5329-0410-9bdc-e9ce6186880e
The subclasses of CallFrameInfo::Rule store the rule currently in
force for recovering a register or computing the canonical frame
address. Their sole responsibility is to accurately convey rules from
the parser, which creates them, to a CallFrameInfo::Handler member
function, which consumes them. So, the types of their data members
should match those of the corresponding arguments of the corresponding
Handler member function.
CallFrameInfo::OffsetRule and CallFrameInfo::ValOffsetRule use an
'int' to store the rule's offset value, but
CallFrameInfo::Handler::OffsetRule and ...::ValOffsetRule expect a
'long'. On ABIs where 'long' is larger than 'int', this can cause
values to be truncated or sign-extended unexpectedly.
This patch changes those members to 'long'.
Fortunately, offsets appearing in real DWARF call frame information
never even come close to the limits of a 32-bit int, so this bug is
unlikely to cause any practical problems.
A=jimb R=thestig
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@615 4c0a9323-5329-0410-9bdc-e9ce6186880e
The comments don't accurately describe what the style guide says.
Regardless of what the style guide says, RTTI seems to make trouble in
practice, because so many people build with it disabled. Since only the
symbol dumper uses RTTI, not the client library, it may be practical for
people to simply enable RTTI for the dumper. Failing that, it may be best
in the long run to violate the style guide and make the code work sans
RTTI.
a=jimblandy, r=mmentovai
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@561 4c0a9323-5329-0410-9bdc-e9ce6186880e
- Use manifest constants for 'z' augmentation letters.
- Fix typos and rearrange some code for legibility.
a=jimblandy, r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@560 4c0a9323-5329-0410-9bdc-e9ce6186880e
Extend google_breakpad::CFISection with the ability to produce
.eh_frame data. Entry headers have a different format, and pointers
can be encoded in new and fascinating ways.
Extend dwarf2reader::CallFrameInfo to be able to parse either DWARF
CFI or .eh_frame data, as determined by an argument to the
constructor. Cope with variations in header formats, encoded pointers,
and additional data in 'z' augmentation data blocks. Extend the unit
tests appropriately.
Extend dump_syms to look for a .eh_frame section, and if it is
present, find the necessary base addresess and parse its contents.
There's no need for DwarfCFIToModule to check the version numbers; if
CallFrameInfo can parse it, DwarfCFIToModule should be able to handle
it. Adjust tests accordingly.
a=jimblandy, r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@552 4c0a9323-5329-0410-9bdc-e9ce6186880e
Define a new DWARF parser class, dwarf2reader::CallFrameInfo.
Extend google_breakpad::Module to store and write out 'STACK CFI' records.
Define a new google_breakpad::DwarfCFIToModule class, to accept DWARF
CFI data from the parser and populate a Module with the equivalent
STACK CFI records.
Extend the Linux symbol dumping tool, dump_syms, to use
dwarf2reader::CallFrameInfo, google_breakpad::DwarfCFIToModule, and
google_breakpad::Module to extract DWARF CFI from the executable or
shared library files and write it to the Breakpad symbol file.
Define CFISection, a new class derived from TestAssembler::Section,
for use in creating DWARF CFI data for test cases.
a=jimblandy, r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@550 4c0a9323-5329-0410-9bdc-e9ce6186880e
This also includes some comments I promised Cary Coutant I'd write
about the appropriateness of processing attributes in EndAttributes
calls.
The Google C++ Style Guide requires each file to have an author notice
and a comment explaining the file's general purpose. For the record, I
don't think putting an author notice on the files is a good idea; it's
odd to have the original author retain prominence even if the file has
been heavily edited by others; the version control system answers this
question more accurately. This is only for Style Guide compliance. The
Apache group decided to discourage author annotations, partially for
these reasons:
http://mail-archives.apache.org/mod_mbox/jakarta-jmeter-dev/200402.mbox/%3C4039F65E.7020406@atg.com%3E
a=jimblandy, r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@518 4c0a9323-5329-0410-9bdc-e9ce6186880e
We've gotten mixed advice from the lawyery types about whether this
matters. But it's easy enough to do.
a=jimblandy, r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@517 4c0a9323-5329-0410-9bdc-e9ce6186880e
This patch moves the ReadInitialFunction from dwarf2reader.cc, where
it was a static function, to being a member function of
google_breakpad::ByteReader.
a=jimblandy, r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@504 4c0a9323-5329-0410-9bdc-e9ce6186880e
