Commit Graph

99 Commits

Author SHA1 Message Date
Eugene Zelenko 570e39a25c [DebugInfo] Fix some Clang-tidy modernize-use-default and Include What You Use warnings; other minor fixes (NFC).
Per Zachary Turner and Mehdi Amini suggestion to make only post-commit reviews.

llvm-svn: 287838
2016-11-23 23:16:32 +00:00
Greg Clayton 6f6e4dbd5d Improve DWARF parsing speed by improving DWARFAbbreviationDeclaration
This patch gets a DWARF parsing speed improvement by having DWARFAbbreviationDeclaration instances know if they have a fixed byte size. If an abbreviation has a fixed byte size that can be calculated given a DWARFUnit, then parsing a DIE becomes two steps: parse ULEB128 abbrev code, and then add constant size to the offset.

This patch also adds a fixed byte size to each DWARFAbbreviationDeclaration::AttributeSpec so that attributes can quickly skip their values if needed without the need to lookup the fixed for size.

Notable improvements:

- DWARFAbbreviationDeclaration::findAttributeIndex() now returns an Optional<uint32_t> instead of a uint32_t and we no longer have to look for the magic -1U return value
- Optional<uint32_t> DWARFAbbreviationDeclaration::findAttributeIndex(dwarf::Attribute attr) const;
- DWARFAbbreviationDeclaration now has a getAttributeValue() function that extracts an attribute value given a DIE offset that takes advantage of the DWARFAbbreviationDeclaration::AttributeSpec::ByteSize
- bool DWARFAbbreviationDeclaration::getAttributeValue(const uint32_t DIEOffset, const dwarf::Attribute Attr, const DWARFUnit &U, DWARFFormValue &FormValue) const;
- A DWARFAbbreviationDeclaration instance can return a fixed byte size for itself so DWARF parsing is faster:
- Optional<size_t> DWARFAbbreviationDeclaration::getFixedAttributesByteSize(const DWARFUnit &U) const;
- Any functions that used to take a "const DWARFUnit *U" that would crash if U was NULL now take a "const DWARFUnit &U" and are only called with a valid DWARFUnit

Differential Revision: https://reviews.llvm.org/D26567

llvm-svn: 286924
2016-11-15 01:23:06 +00:00
Greg Clayton 04c19286a1 Fixed issues found by Paul Robinson with my patch for:
https://reviews.llvm.org/D26526

- Fixed DW_FORM_strp to be correctly sized and extracted for DWARF64
- Added some missing strp variants as well
- Fixed comment typo

llvm-svn: 286603
2016-11-11 17:38:14 +00:00
Greg Clayton 82f12b149f Clean up DWARFFormValue by reducing duplicated code and removing DWARFFormValue::getFixedFormSizes()
In preparation for a follow on patch that improves DWARF parsing speed, clean up DWARFFormValue so that we have can get the fixed byte size of a form value given a DWARFUnit or given the version, address byte size and dwarf32/64.

This patch cleans up code so that everyone is using one of the new DWARFFormValue functions:

static Optional<uint8_t> DWARFFormValue::getFixedByteSize(dwarf::Form Form, const DWARFUnit *U = nullptr);
static Optional<uint8_t> DWARFFormValue::getFixedByteSize(dwarf::Form Form, uint16_t Version, uint8_t AddrSize, bool Dwarf32);

This patch changes DWARFFormValue::skipValue() to rely on the output of DWARFFormValue::getFixedByteSize(...) instead of duplicating the code in each function. This will reduce the number of changes we need to make to DWARF to fewer places in DWARFFormValue when we add support for new form.

This patch also starts to support DWARF64 so that we can get correct byte sizes for forms that vary according the DWARF 32/64.

To reduce the code duplication a new FormSizeHelper pure virtual class was created that can be created as a FormSizeHelperDWARFUnit when you have a DWARFUnit, or FormSizeHelperManual where you manually specify the DWARF version, address byte size and DWARF32/DWARF64. There is now a single implementation of a function that gets the fixed byte size (instead of two where one took a DWARFUnit and one took the DWARF version, address byte size and DWARFFormat enum) and one function to skip the form values.

https://reviews.llvm.org/D26526

llvm-svn: 286597
2016-11-11 16:21:37 +00:00
Greg Clayton cddab279f6 Modify DWARFFormValue to remember the DWARFUnit that it was decoded with.
Modifying DWARFFormValue to remember the DWARFUnit that it was encoded with can simplify the usage of instances of this class. Previously users would have to try and pass in the same DWARFUnit that was used to decode the form value and there was a possibility that a different DWARFUnit might be supplied to the functions that extract values (strings, CU relative references, addresses) and cause problems. This fixes this potential issue by storing the DWARFUnit inside the DWARFFormValue so that this mistake can't be made. Instances of DWARFFormValue are not stored permanently and are used as temporary values, so the increase in size of an instance of DWARFFormValue isn't a big deal. This makes decoding form values more bullet proof and is a change that will be used by future modifications.

https://reviews.llvm.org/D26052

llvm-svn: 285594
2016-10-31 16:46:02 +00:00
Adrian Prantl c4fbbcf9ed Import/update constants from the DWARF 5 public review draft document.
https://reviews.llvm.org/D26051

llvm-svn: 285421
2016-10-28 17:59:50 +00:00
Greg Clayton 6c273763a3 Switch all DWARF variables for tags, attributes and forms over to use the llvm::dwarf enumerations instead of using raw uint16_t values. This allows easier debugging as users can see the values of the enumerations in the variables view that will show the enumeration string instead of just a number.
https://reviews.llvm.org/D26013

llvm-svn: 285309
2016-10-27 16:32:04 +00:00
David Blaikie 69494a9805 dwarfdump: add space missing from the type unit header description
llvm-svn: 284540
2016-10-18 21:18:43 +00:00
David Blaikie e4c3915a5a dwarfdump: Include the name in the unit description, even in non-summarized mode
(accidentally removed this from my previous change when I was rejecting
some clang-format formatting... )

llvm-svn: 284539
2016-10-18 21:16:45 +00:00
David Blaikie 50cc27ecb9 dwarfdump: -summarize-types: print a short summary (unqualified type name, hash, length) of type units rather than dumping contents
This is just a quick utility handy for getting rough summaries of types
in a given object or dwo file. I've been using it to investigate the
amount of type info redundancy across a project build, for example.

llvm-svn: 284537
2016-10-18 21:09:48 +00:00
Mehdi Amini 149f6eaed9 Re-commit "Use StringRef in Support/Darf APIs (NFC)"
This reverts commit r283285 and re-commit r283275 with
a fix for format("%s", Str); where Str is a StringRef.

llvm-svn: 283298
2016-10-05 05:59:29 +00:00
Mehdi Amini 2bcac0fac4 Revert "Re-commit "Use StringRef in Support/Darf APIs (NFC)""
One test seems randomly broken: DebugInfo/X86/gnu-public-names.ll

llvm-svn: 283285
2016-10-05 01:04:02 +00:00
Mehdi Amini 32b297a42f Re-commit "Use StringRef in Support/Darf APIs (NFC)"
This reverts commit r283278 and re-commit r283275 with
the update to fix the build on the LLDB side.

llvm-svn: 283281
2016-10-05 00:37:18 +00:00
Mehdi Amini 78b04ae7ac Revert "Use StringRef in Support/Darf APIs (NFC)"
This reverts commit r283275, it broke LLDB Android debug server.

llvm-svn: 283278
2016-10-05 00:21:14 +00:00
Mehdi Amini e0327be584 Use StringRef in Support/Darf APIs (NFC)
llvm-svn: 283275
2016-10-04 23:55:40 +00:00
George Rimar 4f82df52ae Revert r282238 "Revert r282235 "[llvm-dwarfdump] - Teach dwarfdump to dump gdb-index section.""
Build bot issues (http://lab.llvm.org:8011/builders/clang-x64-ninja-win7/builds/15856/steps/ninja%20check%201/logs/FAIL%3A%20LLVM%3A%3Adwarfdump-dump-gdbindex.test)
should be fixed in that version. Issue was that MSVS does not support "%zu". Though it works fine on MSCS 2015,
Bot looks running MSVS 2013 that does not like it. MSDN also says that "z" prefix is not supported: https://msdn.microsoft.com/en-us/library/tcxf1dw6.aspx
I had to use PRId64 instead.

Original commit message:

[llvm-dwarfdump] - Teach dwarfdump to dump gdb-index section.

gold linker's --gdb-index option currently is able to create the .gdb_index section that allows GDB to locate and read the .dwo files as it needs them,
this helps reduce the total size of the object files processed by the linker.

More info about that:
https://gcc.gnu.org/wiki/DebugFission
https://sourceware.org/gdb/onlinedocs/gdb/Index-Section-Format.html

Patch teaches dwarfdump tool to dump this section.

Differential revision: https://reviews.llvm.org/D21503

llvm-svn: 282239
2016-09-23 11:01:53 +00:00
George Rimar a348527186 Revert r282235 "[llvm-dwarfdump] - Teach dwarfdump to dump gdb-index section."
It broke BB:
http://lab.llvm.org:8011/builders/clang-x64-ninja-win7/builds/15856

llvm-svn: 282238
2016-09-23 10:12:56 +00:00
George Rimar a77bcf5e42 [llvm-dwarfdump] - Teach dwarfdump to dump gdb-index section.
gold linker's --gdb-index option currently is able to create the .gdb_index section that allows GDB to locate and read the .dwo files as it needs them,
this helps reduce the total size of the object files processed by the linker.

More info about that:
https://gcc.gnu.org/wiki/DebugFission
https://sourceware.org/gdb/onlinedocs/gdb/Index-Section-Format.html

Patch teaches dwarfdump tool to dump this section.

Differential revision: https://reviews.llvm.org/D21503

llvm-svn: 282235
2016-09-23 09:09:26 +00:00
Eugene Zelenko 61a72d8850 [LLVM] Fix some Clang-tidy modernize-use-using and Include What You Use warnings
Differential revision: https://reviews.llvm.org/D23675

llvm-svn: 279102
2016-08-18 17:56:27 +00:00
Pete Cooper b2ba776aed Avoid dsymutil calls to getFileNameByIndex.
This change adds a hasFileAtIndex method. getChildDeclContext can first call this method, and if it returns true it knows it can then lookup the resolved path cache for the given file index. If we hit that cache then we don't even have to call getFileNameByIndex.

Running dsymutil against the swift executable built from github gives a 20% performance improvement without any change in the binary.

Differential Revision: https://reviews.llvm.org/D22655

Reviewed by friss.

llvm-svn: 276380
2016-07-22 01:41:32 +00:00
Reid Kleckner dafc5d75ea Prune RelocVisitor.h include to avoid including COFF.h from MCJIT.h
This helps to mitigate the conflict between COFF.h and winnt.h, which is
PR28399.

llvm-svn: 274637
2016-07-06 16:56:42 +00:00
Kevin Enderby 931cb65df2 Thread Expected<...> up from libObject’s getSymbolAddress() for symbols to allow
a good error message to be produced.

This is nearly the last libObject interface that used ErrorOr and the last one
that appears in llvm/include/llvm/Object/MachO.h .  For Mach-O objects this is
just a clean up because it’s version of getSymbolAddress() can’t return an
error.

I will leave it to the experts on COFF and ELF to actually add meaning full
error messages in their tests if they wish.  And also leave it to these experts
to change the last two ErrorOr interfaces in llvm/include/llvm/Object/ObjectFile.h
for createCOFFObjectFile() and createELFObjectFile() if they wish.

Since there are no test cases for COFF and ELF error cases with respect to
getSymbolAddress() in the test suite this is no functional change (NFC).

llvm-svn: 273701
2016-06-24 18:24:42 +00:00
Benjamin Kramer 82de7d323d Apply clang-tidy's misc-move-constructor-init throughout LLVM.
No functionality change intended, maybe a tiny performance improvement.

llvm-svn: 270997
2016-05-27 14:27:24 +00:00
George Rimar 401e4e570e Recommit r270547 ([llvm-dwarfdump] - Teach dwarfdump to decompress debug sections in zlib style.)
Fix was:
1) Had to regenerate dwarfdump-test-zlib.elf-x86-64, dwarfdump-test-zlib-gnu.elf-x86-64
(because llvm-symbolizer-zlib.test uses that inputs for its purposes and failed).
2) Updated llvm-symbolizer-zlib.test (updated used call function address to match new files + 
added one more check for newly created dwarfdump-test-zlib-gnu.elf-x86-64 binary input).
3) Updated comment in dwarfdump-test-zlib.cc.

Original commit message:
[llvm-dwarfdump] - Teach dwarfdump to decompress debug sections in zlib style.

Before this llvm-dwarfdump only recognized zlib-gnu compression style of headers,
this patch adds support for zlib style. 
It looks reasonable to support both styles for dumping,
even if we are not going to suport generating of deprecated gnu one.

Differential revision: http://reviews.llvm.org/D20470

llvm-svn: 270557
2016-05-24 12:48:46 +00:00
George Rimar f059dd4f76 Revert r270543 ("Recommit r270540")
Failed build bot in another test.
I am sorry for noise.
http://lab.llvm.org:8080/green/job/clang-stage1-cmake-RA-incremental_check/23679/testReport/junit/LLVM/DebugInfo/llvm_symbolizer_zlib_test/

llvm-svn: 270547
2016-05-24 11:03:10 +00:00
George Rimar e9b2e19109 Recommit r270540
fix: forgot to commit the updated dwarfdump-test-zlib.elf-x86-64

Original commit message:
[llvm-dwarfdump] - Teach dwarfdump to decompress debug sections in zlib style.

Before this llvm-dwarfdump only recognized zlib-gnu compression style of headers,
this patch adds support for zlib style. 
It looks reasonable to support both styles for dumping,
even if we are not going to suport generating of deprecated gnu one.

Differential revision: http://reviews.llvm.org/D20470

llvm-svn: 270543
2016-05-24 10:46:43 +00:00
George Rimar 6a6185fd78 Revert r270540 "[llvm-dwarfdump] - Teach dwarfdump to decompress debug sections in zlib style."
it broked bot:
http://lab.llvm.org:8011/builders/clang-s390x-linux/builds/5036

llvm-svn: 270541
2016-05-24 09:44:44 +00:00
George Rimar 6bcbf4c572 [llvm-dwarfdump] - Teach dwarfdump to decompress debug sections in zlib style.
Before this llvm-dwarfdump only recognized zlib-gnu compression style of headers,
this patch adds support for zlib style. 
It looks reasonable to support both styles for dumping,
even if we are not going to suport generating of deprecated gnu one.

Differential revision: http://reviews.llvm.org/D20470

llvm-svn: 270540
2016-05-24 09:28:36 +00:00
Kevin Enderby 7bd8d99497 Thread Expected<...> up from libObject’s getType() for symbols to allow llvm-objdump to produce a good error message.
Produce another specific error message for a malformed Mach-O file when a symbol’s
section index is more than the number of sections.  The existing test case in test/Object/macho-invalid.test
for macho-invalid-section-index-getSectionRawName now reports the error with the message indicating
that a symbol at a specific index has a bad section index and that bad section index value.

Again converting interfaces to Expected<> from ErrorOr<> does involve
touching a number of places. Where the existing code reported the error with a
string message or an error code it was converted to do the same.

Also there some were bugs in the existing code that did not deal with the
old ErrorOr<> return values.  So now with Expected<> since they must be
checked and the error handled, I added a TODO and a comment:
"// TODO: Actually report errors helpfully" and a call something like
consumeError(NameOrErr.takeError()) so the buggy code will not crash
since needed to deal with the Error.

llvm-svn: 268298
2016-05-02 20:28:12 +00:00
Dehao Chen 1b54fce319 Read discriminators correctly from object file.
Summary:
This is the follow-up patch for http://reviews.llvm.org/D19436
* Update the discriminator reading algorithm to match the assignment algorithm.
* Add test to cover the new algorithm.

Reviewers: dnovillo, echristo, dblaikie

Subscribers: danielcdh, dblaikie, echristo, llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D19522

llvm-svn: 267945
2016-04-28 22:09:37 +00:00
David Blaikie e438cff475 llvm-symbolizer: Avoid infinite recursion walking dwos where the dwo contains a dwo_name attribute
The dwo_name was added to dwo files to improve diagnostics in dwp, but
it confuses tools that attempt to load any dwo named by a dwo_name, even
ones inside dwos. Avoid this by keeping track of whether a unit is
already a dwo unit, and if so, not loading further dwos.

llvm-svn: 267241
2016-04-22 22:50:56 +00:00
David Blaikie 9a4f3cb275 llvm-symbolizer: prefer .dwo contents over fission-gmlt-like-data when .dwo file is present
Rather than relying on the gmlt-like data emitted into the .o/executable
which only contains the simple name of any inlined functions, use the
.dwo file if present.

Test symbolication with/without a .dwo, and the old test that was
testing behavior when no gmlt-like data was present. (I haven't included
a test of non-gmlt-like data + no .dwo (that would be akin to
symbolication with no debug info) but we could add one for completeness)

The test was simplified a bit to be a little clearer (unoptimized, force
inline, using a function call as the inlined entity) and regenerated
with ToT clang. For the no-gmlt-like-data case, I modified Clang back to
its old behavior temporarily & the .dwo file is identical so it is
shared between the two executables.

llvm-svn: 267227
2016-04-22 21:32:59 +00:00
Mehdi Amini b550cb1750 [NFC] Header cleanup
Removed some unused headers, replaced some headers with forward class declarations.

Found using simple scripts like this one:
clear && ack --cpp -l '#include "llvm/ADT/IndexedMap.h"' | xargs grep -L 'IndexedMap[<]' | xargs grep -n --color=auto 'IndexedMap'

Patch by Eugene Kosov <claprix@yandex.ru>

Differential Revision: http://reviews.llvm.org/D19219

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266595
2016-04-18 09:17:29 +00:00
Richard Smith 2db6f2e508 Update and fix LLVM_ENABLE_MODULES:
1) We need to add this flag prior to adding any other, in case the user has
specified a -fmodule-cache-path= flag in their custom CXXFLAGS. Such a flag
causes -Werror builds to fail, and thus all config checks fail, until we add
the corresponding -fmodules flag. The modules selfhost bot does this, for
instance.

2) Delete module maps that were putting .cpp files into modules.

3) Enable -fmodules-local-submodule-visibility, to get proper module
visibility rules applied across submodules of the same module. Disable
-fmodules for C builds, since that flag is not available there.

llvm-svn: 266502
2016-04-16 00:48:58 +00:00
Kevin Enderby 3fcdf6ae2a Thread Expected<...> up from createMachOObjectFile() to allow llvm-objdump to produce a real error message
Produce the first specific error message for a malformed Mach-O file describing
the problem instead of the generic message for object_error::parse_failed of
"Invalid data was encountered while parsing the file”.  Many more good error
messages will follow after this first one.

This is built on Lang Hames’ great work of adding the ’Error' class for
structured error handling and threading Error through MachOObjectFile
construction.  And making createMachOObjectFile return Expected<...> .

So to to get the error to the llvm-obdump tool, I changed the stack of
these methods to also return Expected<...> :

  object::ObjectFile::createObjectFile()
  object::SymbolicFile::createSymbolicFile()
  object::createBinary()

Then finally in ParseInputMachO() in MachODump.cpp the error can
be reported and the specific error message can be printed in llvm-objdump
and can be seen in the existing test case for the existing malformed binary
but with the updated error message.

Converting these interfaces to Expected<> from ErrorOr<> does involve
touching a number of places. To contain the changes for now use of
errorToErrorCode() and errorOrToExpected() are used where the callers
are yet to be converted.

Also there some were bugs in the existing code that did not deal with the
old ErrorOr<> return values.  So now with Expected<> since they must be
checked and the error handled, I added a TODO and a comment:
“// TODO: Actually report errors helpfully” and a call something like
consumeError(ObjOrErr.takeError()) so the buggy code will not crash
since needed to deal with the Error.

Note there is one fix also needed to lld/COFF/InputFiles.cpp that goes along
with this that I will commit right after this.  So expect lld not to built
after this commit and before the next one.

llvm-svn: 265606
2016-04-06 22:14:09 +00:00
Simon Atanasyan f69c7e5382 [DebugInfo] Dump CIE augmentation data as a list of hex bytes
CIE augmentation data might contain non-printable characters.
The patch prints the data as a list of hex bytes.

Differential Revision: http://reviews.llvm.org/D17759

llvm-svn: 262361
2016-03-01 18:38:05 +00:00
Dmitry Polukhin f4124a72c1 [DebugInfo] Eliminate compilation warning about used variable LSDA
The waring was:
lib/DebugInfo/DWARF/DWARFDebugFrame.cpp:643:20: warning: variable ‘LSDA’ set but not used

llvm-svn: 259877
2016-02-05 09:24:34 +00:00
Igor Laevsky ff291b5833 [DebugInfo] Support zero-length CIE in the _eh_frame parser
MCJIT emits zero-length CIE at the end of the _eh_frame section. This change
ensures that parser inside DebugInfo will not crash and correctly record such cases.
We are now recording DW_EH_PE_omit as a default value for FDE and LSDA encodings.
Also Offset != EndAugmentationOffset assertion check will only happen if augmentation 
string had 'z' letter in it.

Differential Revision: http://reviews.llvm.org/D16588

llvm-svn: 258931
2016-01-27 14:05:35 +00:00
Chris Bieneman e49730d4ba Remove autoconf support
Summary:
This patch is provided in preparation for removing autoconf on 1/26. The proposal to remove autoconf on 1/26 was discussed on the llvm-dev thread here: http://lists.llvm.org/pipermail/llvm-dev/2016-January/093875.html

"I felt a great disturbance in the [build system], as if millions of [makefiles] suddenly cried out in terror and were suddenly silenced. I fear something [amazing] has happened."
- Obi Wan Kenobi

Reviewers: chandlerc, grosbach, bob.wilson, tstellarAMD, echristo, whitequark

Subscribers: chfast, simoncook, emaste, jholewinski, tberghammer, jfb, danalbert, srhines, arsenm, dschuff, jyknight, dsanders, joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D16471

llvm-svn: 258861
2016-01-26 21:29:08 +00:00
Igor Laevsky 03a670c0ec Re-submit r256008 "Improve DWARFDebugFrame::parse to also handle __eh_frame."
Originally this change was causing failures on windows buildbots.
But those problems were fixed in r258806.

llvm-svn: 258811
2016-01-26 15:09:42 +00:00
Igor Laevsky 0e1605a3b4 [DebugInfo] Fix DWARFDebugFrame instruction operand ordering
We can't rely on the evalution order of function arguments.

Differential Revision: http://reviews.llvm.org/D16509

llvm-svn: 258806
2016-01-26 13:31:11 +00:00
Dimitry Andric 227b928abc Fix several accidental DOS line endings in source files
Summary:
There are a number of files in the tree which have been accidentally checked in with DOS line endings.  Convert these to native line endings.

There are also a few files which have DOS line endings on purpose, and I have set the svn:eol-style property to 'CRLF' on those.

Reviewers: joerg, aaron.ballman

Subscribers: aaron.ballman, sanjoy, dsanders, llvm-commits

Differential Revision: http://reviews.llvm.org/D15848

llvm-svn: 256707
2016-01-03 17:22:03 +00:00
Pete Cooper 98052537f0 Revert "Improve DWARFDebugFrame::parse to also handle __eh_frame."
This reverts commit r256008.

Its breaking multiple buildbots, although works for me locally.

llvm-svn: 256013
2015-12-18 19:45:38 +00:00
Pete Cooper 6c97f4c7d7 Improve DWARFDebugFrame::parse to also handle __eh_frame.
LLVM MC has single methods which can handle the output of EH frame and DWARF CIE's and FDE's.

This code improves DWARFDebugFrame::parse to do the same for parsing.

This also allows llvm-objdump to support the --dwarf=frames option which objdump supports.  This
option dumps the .eh_frame section using the new code in DWARFDebugFrame::parse.

http://reviews.llvm.org/D15535

Reviewed by Rafael Espindola.

llvm-svn: 256008
2015-12-18 18:51:08 +00:00
David Blaikie ad07b5d65e [llvm-dwp] Retrieve the DWOID from the CU for the cu_index entry
llvm-svn: 254731
2015-12-04 17:20:04 +00:00
David Blaikie 725c4f71d1 dwarfdump: Correctly indentify the indicies for DWP records
The indicies are one-based, not zero-based, per the spec.

llvm-svn: 254626
2015-12-03 18:41:59 +00:00
David Blaikie 20f52662d4 [llvm-dwp] Don't rely on implicit move assignment operator (MSVC won't synthesize one)
llvm-svn: 254492
2015-12-02 07:09:26 +00:00
David Blaikie b073cb9be2 [llvm-dwp] Emit a rather fictional debug_cu_index
This is very rudimentary support for debug_cu_index, but it is enough to
allow llvm-dwarfdump to find the offsets for  contributions and
correctly dump debug_info.

It will need to actually find the real signature of the unit and build
the real hash table with the right number of buckets, as per the DWP
specification.

It will also need to be expanded to cover the tu_index as well.

llvm-svn: 254489
2015-12-02 06:21:34 +00:00
Craig Topper 66059c9f4d Replace dyn_cast with isa in places that weren't using the returned value for more than a boolean check. NFC.
llvm-svn: 253441
2015-11-18 07:07:59 +00:00
David Blaikie 4689ef5943 Fix null dereference committed in r253277
llvm-svn: 253393
2015-11-17 22:39:26 +00:00