Commit Graph

370 Commits

Author SHA1 Message Date
Paul Robinson 7947468e69 [DWARF] Replace assert with diagnostic. PR36868.
llvm-svn: 328235
2018-03-22 19:37:56 +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
Rafael Espindola c51dc906ea Handle abbr_offset with relocations.
This is mostly just plumbing to get a DWARFDataExtractor where we
compute abbr_offset so we can use getRelocatedValue.

This is part of PR36793.

llvm-svn: 328154
2018-03-21 21:31:25 +00:00
Pavel Labath 9025f9559d [dwarf] Unify unknown dwarf enum formatting code
Summary:
We have had at least three pieces of code (in DWARFAbbreviationDeclaration,
DWARFAcceleratorTable and DWARFDie) that have hand-rolled support for
dumping unknown dwarf enum values. While not terrible, they are a bit
distracting and enable small differences to creep in (Unknown_ffff vs.
Unknown_0xffff). I ended up needing to add a fourth place
(DWARFVerifier), so it seems it would be a good time to centralize.

This patch creates an alternative to the XXXString dumping functions in
the BinaryFormat library, which formats an unknown value as
DW_TYPE_unknown_1234, instead of just an empty string. It is based on
the formatv function, as that allows us to avoid materializing the
string for unknown values (and because this way I don't have to invent a
name for the new functions :P).

In this patch I add formatters for dwarf attributes, forms, tags, and
index attributes as these are the ones in use currently, but adding
other enums is straight-forward.

Reviewers: dblaikie, JDevlieghere, aprantl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D44570

llvm-svn: 328090
2018-03-21 11:46:37 +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 322711f529 DWARF: Unify form size handling code
Summary:
This patch replaces the two switches which are deducing the size of
various forms with a single implementation. I have put the new
implementation into BinaryFormat, to avoid introducing dependencies
between the two independent libraries (DebugInfo and CodeGen) that need
this functionality.

Reviewers: aprantl, JDevlieghere, dblaikie

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D44418

llvm-svn: 327486
2018-03-14 09:39:54 +00:00
Eugene Zemtsov 82d60d6b29 Handle mixed-OS paths in DWARF reader
Make sure that DWARF line information generated by Windows can be properly read by Posix OS and vice versa.

Differential Revision: https://reviews.llvm.org/D44290

llvm-svn: 327430
2018-03-13 17:54:29 +00:00
Jonas Devlieghere b4c85cf4a4 [DebugInfo] Replace unreachable with None
Invalid user input should not trigger assertions and unreachables. We
already return an Option so we should just return None here.

Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=5532

llvm-svn: 327274
2018-03-12 14:45:08 +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
Jonas Devlieghere 6921753994 [Support] Move syntax highlighting into support
Move the DWARF syntax highlighting into support. This has several
advantages, most notably that this makes the WithColor RAII wrapper
available outside libDebugInfo. Furthermore, several projects all have
their own code for handling colored output. This provides a place to
centralize it.

Differential revision: https://reviews.llvm.org/D44215

llvm-svn: 327108
2018-03-09 09:56:24 +00:00
Benjamin Kramer 70e6faaa0d [DebugInfo] Move RangeListEntries instead of copying.
This is needed for correctness as RangeListEntry is not copy-assignable,
which std::vector might rely on.

llvm-svn: 327067
2018-03-08 21:31:10 +00:00
Zachary Turner 145bc6e0d3 Fix compilation failure with MSVC.
llvm-svn: 327063
2018-03-08 21:07:30 +00:00
Wolfgang Pieb a0729d4126 [DWARF v5] Support for verbose dumping of .debug_rnglist entries
Adding verbose dumping to the recent implementation of dumping of v5 range list entries. 
We're capturing the entries as is as they come in during extraction, including their file offset,
so we can dump them in more detail.
The offset table entries which are table-relative are shown as is (as in non-verbose mode)
and with the actual file offset they map to.

Reviewers: dblaikie, aprantl, jdevlieghere, jhenderson

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D43366

llvm-svn: 327059
2018-03-08 20:52:35 +00:00
Pavel Labath b136c3934e DWARFVerifier: Basic verification of .debug_names
Summary:
This patch adds basic .debug_names verification capabilities to the
DWARF verifier. Right now, it checks that the headers and abbreviation
tables of the individual name indexes can be parsed correctly, it
verifies the buckets table and the cross-checks the CU lists for
consistency. I intend to add further checks in follow-up patches.

Reviewers: JDevlieghere, aprantl, probinson, dblaikie

Subscribers: vleschuk, echristo, clayborg, llvm-commits

Differential Revision: https://reviews.llvm.org/D44211

llvm-svn: 327011
2018-03-08 15:34:42 +00:00
James Henderson 667026297d [DWARF] Don't attempt to parse line tables at invalid offsets
Whilst working on improvements to the error handling of the debug line
parsing code, I noticed that if an invalid offset were to be specified
in a call to getOrParseLineTable(), an entry in the LineTableMap would
still be created, even if the offset was not within the section range.
The immediate parsing attempt afterwards would fail (it would end up
getting a version of 0), and thereafter, any subsequent calls to
getOrParseLineTable or getLineTable would return the default-
constructed, invalid line table. In reality, we shouldn't even attempt
to parse this table, and we should always return a nullptr from these
two functions for this situation.

I have tested this via a unit test, which required some new framework
for unit testing debug line. My plan is to add quite a few more unit
tests for the new error reporting mechanism that will follow shortly,
hence the reason why the supporting code for the tests are written the
way they are - I intend to extend the DwarfGenerator class to support
generating debug line. At that point, I'll make sure that there are a
few positive test cases for this and the parsing code too.

Differential Revision: https://reviews.llvm.org/D44200

Reviewers: JDevlieghere, aprantl
llvm-svn: 326995
2018-03-08 10:53:34 +00:00
Rafael Auler 86fb7bf2bc Reland "[DebugInfo] Support DWARF expressions in eh_frame"
Summary:
Original change was D43313 (r326932) and reverted by r326953 because it
broke an LLD test and a windows build. The LLD test was already fixed in
lld commit r326944 (thanks maskray). This is the original change with
the windows build fixed.

llvm-svn: 326970
2018-03-08 00:46:53 +00:00
Rui Ueyama 6aa8b3491f Revert r326932: [DebugInfo] Support DWARF expressions in eh_frame
This reverts commit rr326932 because it broke lld/test/ELF/eh-frame-hdr-augmentation.s.

llvm-svn: 326953
2018-03-07 22:29:48 +00:00
Rafael Auler 7fdf44440c [DebugInfo] Support DWARF expressions in eh_frame
This patch enhances DWARFDebugFrame with the capability of parsing and
printing DWARF expressions in CFI instructions. It also makes FDEs and
CIEs accessible to lib users, so they can process them in client tools
that rely on LLVM. To make it self-contained with a test case, it
teaches llvm-readobj to be able to dump EH frames and checks they are
correct in a unit test. The llvm-readobj code is Maksim Panchenko's work
(maksfb).

Reviewers: JDevlieghere, espindola

Reviewed By: JDevlieghere

Differential Revision: https://reviews.llvm.org/D43313

llvm-svn: 326932
2018-03-07 19:19:51 +00:00
Jonas Devlieghere bf8596f9cf [dwarfdump] Only print CU relative offset in verbose mode
Instead of only printing the CU-relative offset in non-verbose mode, it
makes more sense to only printed the resolved address. In verbose mode
we still print both.

Differential revision: https://reviews.llvm.org/D44148

rdar://33525475

llvm-svn: 326903
2018-03-07 16:28:53 +00:00
Pavel Labath d99072bc97 Implement equal_range for the DWARF v5 accelerator table
Summary:
This patch implements the name lookup functionality of the .debug_names
accelerator table and hooks it up to "llvm-dwarfdump -find". To make the
interface of the two kinds of accelerator tables more consistent, I've
created an abstract "DWARFAcceleratorTable::Entry" class, which provides
a consistent interface to access the common functionality of the table
entries (such as getting the die offset, die tag, etc.). I've also
modified the apple table to vend entries conforming to this interface.

Reviewers: JDevlieghere, aprantl, probinson, dblaikie

Subscribers: vleschuk, clayborg, echristo, llvm-commits

Differential Revision: https://reviews.llvm.org/D43067

llvm-svn: 326003
2018-02-24 00:35:21 +00:00
Scott Linder 16c7bdaf32 [DebugInfo] Support DWARF v5 source code embedding extension
In DWARF v5 the Line Number Program Header is extensible, allowing values with
new content types. In this extension a content type is added,
DW_LNCT_LLVM_source, which contains the embedded source code of the file.

Add new optional attribute for !DIFile IR metadata called source which contains
source text. Use this to output the source to the DWARF line table of code
objects. Analogously extend METADATA_FILE in Bitcode and .file directive in ASM
to support optional source.

Teach llvm-dwarfdump and llvm-objdump about the new values. Update the output
format of llvm-dwarfdump to make room for the new attribute on file_names
entries, and support embedded sources for the -source option in llvm-objdump.

Differential Revision: https://reviews.llvm.org/D42765

llvm-svn: 325970
2018-02-23 23:01:06 +00:00
Jonas Devlieghere 7d4a974d8b [dwarfdump] Fix spurious verification errors for DW_AT_location attributes
Verifying any DWARF file that is optimized and contains at least one tag
with a DW_AT_location with a location list offset as a
DW_AT_form_dataXXX results in dwarfdump spuriously claiming that the
location list is invalid.

Differential revision: https://reviews.llvm.org/D40199

llvm-svn: 325430
2018-02-17 13:06:37 +00:00
David Blaikie 3b6de6fe1c Revert "Rewrite the cached map used for locating the most precise DIE among inlined subroutines for a given address."
Seeing some inlining missing in internal uses of symbolizer. I'll work
on a reproduction, tests, improvements & recommit as soon as possible.

(Chandler would like it to be known that this improvement did make
check-llvm 4x faster... - so there's certainly some fairly good
motivation to push on fixing/figuring this out & getting it back in)

This reverts commit r321345.

llvm-svn: 324981
2018-02-13 01:52:30 +00:00
Adrian Prantl a5eee4de07 Simplify switch statement (NFC)
llvm-svn: 324945
2018-02-12 22:09:57 +00:00
Adrian Prantl 520789e139 Fix the syntax highlighting of strings in dwarfdump.
llvm-svn: 324936
2018-02-12 21:11:23 +00:00
Adrian Prantl baf9c20b02 Factor out common condition into an easier to understand helper function (NFC).
llvm-svn: 324935
2018-02-12 21:11:14 +00:00
Paul Robinson ceafcd41cf [DWARFv5] Fix dumper to show the file table starts at index 0.
Emitting the correct (root of compilation) file at index 0 will be
posted for review later; I wanted to get this minor change out of the
way first.

llvm-svn: 324669
2018-02-08 23:08:02 +00:00
Paul Robinson 0a22709f06 [DWARF] Regularize dumping strings from line tables.
The major visible difference here is that in line-table dumps,
directory and file names are wrapped in double-quotes; previously,
directory names got single quotes and file names were not quoted at
all.

The improvement in this patch is that when a DWARF v5 line table
header has indirect strings, in a verbose dump these will all have
their section[offset] printed as well as the name itself.  This
matches the format used for dumping strings in the .debug_info
section.

Differential Revision: https://reviews.llvm.org/D42802

llvm-svn: 324270
2018-02-05 20:43:15 +00:00
James Henderson 10392cdbf7 Fix more print format specifiers in debug_rnglists dumping
See also r324096.

I have made the assumption that DWARF64 is not an issue for the time
being with these fixes.

llvm-svn: 324223
2018-02-05 10:47:13 +00:00
Simon Pilgrim 3d5ee7aa41 Fix MSVC signed/unsigned comparison warning. NFCI.
llvm-svn: 324171
2018-02-03 12:38:56 +00:00
James Henderson 2465633234 Fix type sizes that were causing incorrect string formatting
llvm-svn: 324096
2018-02-02 15:09:31 +00:00
James Henderson c2dfd502a2 Add missing new files from r324077
Differential Revision: https://reviews.llvm.org/D42481

llvm-svn: 324078
2018-02-02 12:45:57 +00:00
James Henderson 3fcc74500a [DWARF v5] Add limited support for dumping .debug_rnglists
This change adds support to llvm-dwarfdump for dumping DWARF5
.debug_rnglists sections in regular ELF files.

It is not complete, in that several DW_RLE_* encodings are currently
not supported, but does dump the headert and the basic ranges for
DW_RLE_start_length and DW_RLE_start_end encodings.

Obvious next steps are to add verbose dumping that dumps the raw
encodings, rather than the interpreted contents, to add -verify support
of the section (e.g. to show that the correct number of offsets are
specified), add dumping of .debug_rnglists.dwo, and to add support for
other encodings.

Reviewed by: dblaikie, JDevlieghere

Differential Revision: https://reviews.llvm.org/D42481

llvm-svn: 324077
2018-02-02 12:35:52 +00:00
Paul Robinson d0c89f851b Stop tracking .debug_line_str in DWARFUnit. NFC.
llvm-svn: 323701
2018-01-29 22:02:56 +00:00
Paul Robinson bf750c80e9 [DWARFv5] Re-enable dumping a line table with no CU.
r323476 added support for DW_FORM_line_strp, and incorrectly made that
depend on having a DWARFUnit available.  We shouldn't be tracking
.debug_line_str in DWARFUnit after all.  After this patch, I can do an
NFC follow up and undo a bunch of the "plumbing" part of r323476.

Differential Revision: https://reviews.llvm.org/D42609

llvm-svn: 323691
2018-01-29 20:57:43 +00:00
Pavel Labath e7264106d4 Fix windows test failure caused by r323638
The test was failing because of an incorrect sizeof check in the name
index parsing code. This code was meant to check that we have enough
input to parse the fixed-size part of the dwarf header, which it did by
comparing the input to sizeof(Header). Originally struct Header only
contained the fixed-size part, but during review, we've moved additional
members into it, which rendered the sizeof check invalid.

I resolve this by moving the fixed-size part to a separate struct and
updating the sizeof-expression to use that.

llvm-svn: 323648
2018-01-29 13:53:48 +00:00
Pavel Labath 3460957ea3 Fix build broken by r323641
The call to ScopedPrinter::printNumber with size_t argument was
ambiguous (I think) on 32-bit builds. Explicitly cast to a 64-bit int to
avoid this.

llvm-svn: 323642
2018-01-29 11:53:46 +00:00
Pavel Labath 394e805668 Refactor dwarfdump -apple-names output
Summary:
This modifies the dwarfdump output to align it with the new .debug_names
dump. It also renames two header fields to match similar fields in the
dwarf5 header.

A couple of tests needed to be updated to match new output. The changes
were fairly straight-forward, although not really automatable.

Reviewers: JDevlieghere, aprantl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D42415

llvm-svn: 323641
2018-01-29 11:33:17 +00:00
Pavel Labath 3c9a918c9e [DebugInfo] Basic .debug_names dumping support
Summary:
This commit renames DWARFAcceleratorTable to AppleAcceleratorTable to free up
the first name as an interface for the different accelerator tables.
Then I add a DWARFDebugNames class for the dwarf5 table.

Presently, the only common functionality of the two classes is the dump()
method, because this is the only method that was necessary to implement
dwarfdump -debug-names; and because the rest of the
AppleAcceleratorTable interface does not directly transfer to the dwarf5
tables (the main reason for that is that the present interface assumes
the tables are homogeneous, but the dwarf5 tables can have different
keys associated with each entry).

I expect to make the common interface richer as I add more functionality
to the new class (and invent a way to represent it in generic way).

In terms of sharing the implementation, I found the format of the two
tables sufficiently different to frustrate any attempts to have common
parsing or dumping code, so presently the implementations share just low
level code for formatting dwarf constants.

Reviewers: vleschuk, JDevlieghere, clayborg, aprantl, probinson, echristo, dblaikie

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D42297

llvm-svn: 323638
2018-01-29 11:08:32 +00:00
Jonas Devlieghere 92ac9d3e1b [Support] Move DJB hash to support. NFC
This patch moves the DJB hash to support. This is consistent with other
hashing algorithms living there. The hash is used by the DWARF
accelerator tables. We're doing this now because the hashing function is
needed by dsymutil and we don't want to link against libBinaryFormat.

Differential revision: https://reviews.llvm.org/D42594

llvm-svn: 323616
2018-01-28 11:05:10 +00:00
Paul Robinson 0115844c2f [DWARFv5] Classify all the new forms. NFC.
Move standard forms from a switch statement to the table of forms;
fill in all the missing ones defined in DWARF v5.  I'm guessing at
classifications in a couple of cases where v5 forms aren't actually
supported yet, but whoever adds support for the forms can fix the
classifications as needed.

llvm-svn: 323481
2018-01-25 23:06:36 +00:00
Paul Robinson b6aa01ca99 [DWARFv5] Support DW_FORM_line_strp in llvm-dwarfdump.
This form is like DW_FORM_strp, but points to .debug_line_str instead
of .debug_str as the string section.  It's intended to be used from
the line-table header, and allows string-pooling of directory and
filenames across compilation units.

Differential Revision: https://reviews.llvm.org/D42553

llvm-svn: 323476
2018-01-25 22:02:36 +00:00
Pavel Labath 9b36fd2541 Rename DwarfAcceleratorTable to AppleAcceleratorTable. NFC
This frees up the first name to be used as an base class for the
apple table and the dwarf5 .debug_names accel table. The rename  was
split off from D42297 (adding of debug_names support), which is still
under review.

llvm-svn: 323113
2018-01-22 13:17:23 +00:00
Paul Robinson 8181d23b3d [DWARFv5] Number the line-table's directory array correctly.
The compilation directory has always been #0, but as of DWARF v5 it is
explicitly listed in the line-table section instead of implicitly
being a reference to the compile_unit DIE's DW_AT_comp_dir attribute.
This means the dumper should number the dumped array starting with 0
or 1 depending on the DWARF version of the line table.

References in the generated DWARF are correct, it's just the dumper
that was wrong.  Also some assembler-coded tests were similarly
confused about directory numbers.

llvm-svn: 322884
2018-01-18 20:33:35 +00:00
Jonas Devlieghere 6f24c8778c [DebugInfo] Unify dumping of address ranges
Summary:
This patch unifies the printing of address ranges as [0x0, 0x1).

rdar://34822059

Reviewers: aprantl, dblaikie

Subscribers: mehdi_amini, llvm-commits

Differential Revision: https://reviews.llvm.org/D42056

llvm-svn: 322543
2018-01-16 11:17:57 +00:00
Adrian Prantl 146ed408f4 dwarfdump: Match the --uuid output with that of Darwin dwarfdump.
This option is widely used by scripts and there is no reason to break them.

rdar://problem/36032398

llvm-svn: 321901
2018-01-05 21:44:17 +00:00
Jonas Devlieghere cbf651f739 [DebugInfo] Don't crash when given invalid DWARFv5 line table prologue.
This patch replaces an assertion with an explicit check for the validity
of the FORM parameters. The assertion was triggered when the DWARFv5
line table contained a zero address size.

This fixes OSS-Fuzz Issue 4644
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=4644

Differential revision: https://reviews.llvm.org/D41615

llvm-svn: 321863
2018-01-05 10:03:02 +00:00
Chandler Carruth 54a5ad3681 Rewrite the cached map used for locating the most precise DIE among
inlined subroutines for a given address.

This is essentially the hot path of llvm-symbolizer when extracting
inlined frames during symbolization. Previously, we would read every
subprogram and every inlined subroutine, building a std::map across the
entire PC space to the best DIE, and then do only a handful of queries
as we symbolized a backtrace. A huge fraction of the time was spent
building the map itself.

This patch changes it two a two-level system. First, we just build a map
from PC-interval to DWARF subprograms. These are required to be disjoint
and so constructing this is pretty easy. Second, we build a map *just*
for the inlined subroutines within the subprogram containing the query
address. This allows us to look at far fewer DIEs and build a *much*
smaller set of cached maps in the llvm-symbolizer case where only a few
address get symbolized during the entire run.

It also builds both interval maps in a very different way. It constructs
a single flat vector of pairs that maps from offset -> index. The
indices point into collections of DIE objects, but can also be
"tombstones" (-1) to mark gaps. In the case of subprograms, this mostly
just simplifies the data structure a bit. For inlined subroutines,
because we carefully split them as we build the map, we end up in many
cases having no holes and not having to store both start and stop
offsets.

Finally, the PC ranges for the inlined subroutines are compressed into
32-bits by making them relative to the base PC of the outer subprogram.
This means that if you have a single function body with over 2gb of
executable code in it, we will stop mapping address past the first 2gb
of that function into inlined subroutines and just give you the
subprogram. This doesn't seem like a problem. ;]

All of this combines to make llvm-symbolizer *well* over 2x faster for
symbolizing backtraces out of LLVM's unittests. Death-test heavy unit
tests are running >2x faster. I'm still going to look at completely
disabling symbolization there, but figured while I had a good benchmark
we should make symbolization a bit better.

Sadly, the logic to build the flat interval map for the inlined
subroutines is fairly complex. I'm not super happy about this and
welcome any simplifying suggestions.

Huge thanks to Dave Blaikie who helped walk me through what the various
things I needed to do in DWARF to make this work.

Differential Revision: https://reviews.llvm.org/D40987

llvm-svn: 321345
2017-12-22 06:41:23 +00:00
Wolfgang Pieb b4ba1aa486 [DWARF] Fix formatting bug with r321295. This fixes a MIPS buildbot failure.
llvm-svn: 321330
2017-12-22 01:12:24 +00:00
Wolfgang Pieb 6ecd6a8088 [DWARF v5] Rework of string offsets table reader
Reorganizes the DWARF consumer to derive the string offsets table 
contribution's format from the contribution header instead of 
(incorrectly) from the unit's format.

Reviewers: JDevliegehere, aprantl

Differential Revision: https://reviews.llvm.org/D41146
 

llvm-svn: 321295
2017-12-21 19:38:13 +00:00