This makes llvm-pdbdump available on all platforms, although it
will currently fail to create a dumper if there is no PDB reader
implementation for the current platform.
It implements dumping of compilands and children, which is less
information than was previously available, but it has to be
rewritten from scratch using the new set of interfaces, so the
rest of the functionality will be added back in subsequent commits.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228755 91177308-0d34-0410-b5e6-96231b3b80d8
This implements DebugInfoPDB when the DIA SDK is present on the system.
Specifically, this means that the following conditions are met:
1) You are building on Windows.
2) You are building with MSVC.
3) Visual Studio did not corrupt the installation of DIA due to a
known issue with side-by-side installations of VS2012 and VS2013.
If all of these conditions are true, you will be able to pass a value
of PDB_Reader::DIA to PDB::createPdbReader().
There are no tests for this yet, as any test will be in the form of a
lit test which tests the llvm-pdbdump.exe, which still needs to be
rewritten in terms of this library.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228747 91177308-0d34-0410-b5e6-96231b3b80d8
Dumping a symbol often requires access to data that isn't inside
the symbol hierarchy, but which is only accessible through the
top-level session. This patch is a pure interface change to give
symbols a reference to the session.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228542 91177308-0d34-0410-b5e6-96231b3b80d8
This patch implements a few of the optional suggestions from the
initial patch comitting libpdb. In particular, it implements a
virtual function out of line for each of the concrete classes.
A few other minor cleanups exist as well, such as using override
instead of virtual, etc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228516 91177308-0d34-0410-b5e6-96231b3b80d8
These were originally submitted as part of r228428, but this part
caused a build breakage in LLVMConfig. The library portion was
resubmitted independently since it was not causing breakage.
There were two reasons this was causing the build to fail. The
first is that there were no Makefiles added for the PDB tests. And
the second is that the DebugInfoPDB library was only being built by
CMake behind an "if (MSVC)" check. This is wrong since this the
library hides platform specific details, and it was causing
LLVM-Config to not find the library when trying to build unittests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228482 91177308-0d34-0410-b5e6-96231b3b80d8
This change resubmits the patch that broke the build, this time
without unittests. The unittests will be submitted separately
after the problem has been addressed:
--Original Commit Message--
Create lib/DebugInfo/PDB.
This patch creates a platform-independent interface to a PDB reader.
There is currently no implementation of this interface, which will
be provided in future patches. This defines the basic object model
which any implementation must conform to.
Reviewed by: David Blaikie
Differential Revision: http://reviews.llvm.org/D7356
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228435 91177308-0d34-0410-b5e6-96231b3b80d8
This patch creates a platform-independent interface to a PDB reader.
There is currently no implementation of this interface, which will
be provided in future patches. This defines the basic object model
which any implementation must conform to.
Reviewed by: David Blaikie
Differential Revision: http://reviews.llvm.org/D7356
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228428 91177308-0d34-0410-b5e6-96231b3b80d8
In preparation for adding PDB support to LLVM, this moves the
DWARF parsing code to its own subdirectory under DebugInfo, and
renames LLVMDebugInfo to LLVMDebugInfoDWARF.
This is purely a mechanical / build system change.
Differential Revision: http://reviews.llvm.org/D7269
Reviewed by: Eric Christopher
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227586 91177308-0d34-0410-b5e6-96231b3b80d8
utils/sort_includes.py.
I clearly haven't done this in a while, so more changed than usual. This
even uncovered a missing include from the InstrProf library that I've
added. No functionality changed here, just mechanical cleanup of the
include order.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225974 91177308-0d34-0410-b5e6-96231b3b80d8
dsymutil needs access to DWARF specific inforamtion, the small DIContext
wrapper isn't sufficient. Other DWARF consumers might want to use it too
(I'm looking at you lldb).
Differential Revision: http://reviews.llvm.org/D6694
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224594 91177308-0d34-0410-b5e6-96231b3b80d8
Add in definedness checks for shift operators, null checks when
pointers are assumed by the code to be non-null, and explicit
unreachables.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224255 91177308-0d34-0410-b5e6-96231b3b80d8
As dump() methods should be. To allow that, do not store the DWARFFormValue
objects used for the dump in the header data.
Per Alexey's suggestion!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222436 91177308-0d34-0410-b5e6-96231b3b80d8
ELF targets (and maybe COFF) use relocations when referring
to strings in the .debug_str section. Handle that in the
accelerator table dumper. This commit restores the
test/DebugInfo/cross-cu-inlining.ll test to its expected
platform independant form, validating that the fix works
(this test failed on linux boxes).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222029 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r221842 which was a revert of r221836 and of the
test parts of r221837.
This new version fixes an UB bug pointed out by David (along with
addressing some other review comments), makes some dumping more
resilient to broken input data and forces the accelerator tables
to be dumped in the tests where we use them (this decision is
platform specific otherwise).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222003 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r221836.
The tests are asserting on some buildbots. This also reverts the
test part of r221837 as it relies on dwarfdump dumping the
accelerator tables.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221842 91177308-0d34-0410-b5e6-96231b3b80d8
The class used for the dump only allows to dump for the moment, but
it can (and will) be easily extended to support search also.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221836 91177308-0d34-0410-b5e6-96231b3b80d8
Currently FormValues are only used for attributes of DIEs and thus
uers always have a CU lying around when calling into the FormValue
API.
Accelerator tables encode their information using the same Forms
as the attributes, thus it is natural to use DWARFFormValue to
extract/dump them. There is no CU in that case though. Allow the
API to be called with a null CU arguemnt by making the RelocMap
lookup conditional on the CU pointer validity. And document this
new behvior in the header. (Test coverage for this use of the API
comes in the DwarfAccelTable support patch)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221835 91177308-0d34-0410-b5e6-96231b3b80d8
This change depends on the ApplePropertyString helper that I sent spearately.
Not sure how you want this tested: as a tool test by adding a binary to dump, or as an llvm test starting from an IR file?
Reviewers: dblaikie, samsonov
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5689
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219507 91177308-0d34-0410-b5e6-96231b3b80d8
DW_AT_specification and DW_AT_abstract_origin resolving was only performed
on subroutine DIEs because it used the getSubroutineName method. Introduce
a more generic getName() and use it to dump the reference attributes.
Testcases have been updated to check the printed names instead of the offsets
except when the name could be ambiguous.
Reviewers: dblaikie, samsonov
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5625
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219506 91177308-0d34-0410-b5e6-96231b3b80d8
There are two methods in SectionRef that can fail:
* getName: The index into the string table can be invalid.
* getContents: The section might point to invalid contents.
Every other method will always succeed and returning and std::error_code just
complicates the code. For example, a section can have an invalid alignment,
but if we are able to get to the section structure at all and create a
SectionRef, we will always be able to read that invalid alignment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219314 91177308-0d34-0410-b5e6-96231b3b80d8
DWARF in COFF utilizes several relocations. Implement support for them
in RelocVisitor to support llvm-dwarfdump.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219280 91177308-0d34-0410-b5e6-96231b3b80d8
It would be more convenient to pass DWARFSection into DWARFUnitSection
constructor, instead of passing its components (Data and RelocAddrMap)
as a separate arguments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219252 91177308-0d34-0410-b5e6-96231b3b80d8
There will be multiple TypeUnits in an unlinked object that will be extracted
from different sections. Now that we have DWARFUnitSection that is supposed
to represent an input section, we need a DWARFUnitSection<TypeUnit> per
input .debug_types section.
Once this is done, the interface is homogenous and we can move the Section
parsing code into DWARFUnitSection.
This is a respin of r218513 that got reverted because it broke some builders.
This new version features an explicit move constructor for the DWARFUnitSection
class to workaround compilers unable to generate correct C++11 default
constructors.
Reviewers: samsonov, dblaikie
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5482
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218606 91177308-0d34-0410-b5e6-96231b3b80d8
Users of getSectionContents shouldn't try to pass in BSS or virtual
sections. In all instances, this is a bug in the code calling this
routine.
N.B. Some COFF implementations (like CL) will mark their BSS sections as
taking space on disk. This would confuse COFFObjectFile into thinking
the section is larger than the file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218549 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r218513.
Buildbots using libstdc++ issue an error when trying to copy
SmallVector<std::unique_ptr<>>. Revert the commit until we have a fix.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218514 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
There will be multiple TypeUnits in an unlinked object that will be extracted
from different sections. Now that we have DWARFUnitSection that is supposed
to represent an input section, we need a DWARFUnitSection<TypeUnit> per
input .debug_types section.
Once this is done, the interface is homogenous and we can move the Section
parsing code into DWARFUnitSection.
Reviewers: samsonov, dblaikie
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5482
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218513 91177308-0d34-0410-b5e6-96231b3b80d8
This change replaces the brittle if/else chain of string comparisons
with a switch statement on the detected target triple, removing the
need for testing arbitrary architecture names returned from
getFileFormatName, whose primary purpose seems to be for display
(user-interface) purposes. The visitor now takes a reference to the
object file, rather than its arbitrary file format name to figure out
whether the file is a 32 or 64-bit object file and what the detected
target triple is.
A set of tests have been added to help show that the refactoring processes
relocations for the same targets as the original code.
Patch by Charlie Turner.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218406 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit faac033f73.
The test depends on all targets to be enabled in llc in order to pass,
and needs to be rewritten/refactored to not have that dependency.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218393 91177308-0d34-0410-b5e6-96231b3b80d8
This change replaces the brittle if/else chain of string comparisons
with a switch statement on the detected target triple, removing the
need for testing arbitrary architecture names returned from
getFileFormatName, whose primary purpose seems to be for display
(user-interface) purposes. The visitor now takes a reference to the
object file, rather than its arbitrary file format name to figure out
whether the file is a 32 or 64-bit object file and what the detected
target triple is.
A set of tests have been added to help show that the refactoring processes
relocations for the same targets as the original code.
Patch by Charlie Turner.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218388 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: getSubroutineName is currently only used by llvm-symbolizer, thus add a binary test containing a cross-cu inlining example.
Reviewers: samsonov, dblaikie
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5394
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218245 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
getFileNameForUnit() is basically a wrapper around LineTable::getFileNameByIndex().
Fold its additional functionality (adding the DWARFUnit compilation dir) into
LineTable::getFileNameByIndex().
getFileLineInfoForCompileUnit() is a wrapper around getFileNameForUnit(). As
a function to search the line information by address, it seems natural to put
it in the LineTable also.
Before this commit only the Context with its private helpers could do Linetable
lookups. This newly exposed feature will be used by the DIE dumping code to
get access to file information referenced in DIE attributes.
This commit has already been partly reviewed in D5192 and contained an
additional and a bit controversial 'realpath' call that is left out of this
patch. We can reinstate that realpath code later if it is desirable.
Test Plan:
The patch contains no tests as it should be functionally equivalent to the
previous code. As requested in the last review, I checked if the relative
path handling copied from the Context to LineTable::getFileNameByIndex()
was covered, and indeed the symbolizer tests fail if it is removed.
Reviewers: dblaikie, echristo, aprantl, samsonov
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5354
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218125 91177308-0d34-0410-b5e6-96231b3b80d8
The current code is only able to return the right unit if the passed offset
is the exact offset of a section. Generalize the search function by comparing
againt the offset of the next unit instead and by switching the search
algorithm to upper_bound.
This way, the unit returned is the first unit with a getNextUnitOffset()
strictly greater than the searched offset, which is exactly what we want.
Note that there is no need for testing the range of the resulting unit as
the offsets of a DWARFUnitSection are in a single contiguous range from
0 inclusive to lastUnit->getNextUnitOffset() exclusive.
Reviewers: dblaikie samsonov
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5262
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218040 91177308-0d34-0410-b5e6-96231b3b80d8
Use fully qualified name inside a typedef from llvm::iterator_range<...> to
iterator_range. This is reported (rightly I think) by GCC as an
ambiguous name redefinition. Hope this fixes the buildbots.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217751 91177308-0d34-0410-b5e6-96231b3b80d8
A DWARFUnitSection is the collection of Units that have been extracted from
the same debug section.
By embeding a reference to their DWARFUnitSection in each unit, the DIEs
will be able to resolve inter-unit references by interrogating their Unit's
DWARFUnitSection.
This is a minimal patch where the DWARFUnitSection is-a SmallVector of Units,
thus exposing exactly the same interface as before. Followup-up patches might
change from inheritance to composition in order to expose only the wanted
DWARFUnitSection abstraction.
Differential Revision: http://reviews.llvm.org/D5310
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217747 91177308-0d34-0410-b5e6-96231b3b80d8
Forge a test case where llvm-symbolizer has to use external .dwo
file to produce the inlining information.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217270 91177308-0d34-0410-b5e6-96231b3b80d8
The DWARFContext will be used to pass global 'context' down, like
pointers to related debug info sections or command line options.
The first use will be for the debug_info dumper to be able to access
other debug info section to dump eg. Location Expression inline
in the debug_info dump.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217128 91177308-0d34-0410-b5e6-96231b3b80d8
Owning the buffer is somewhat inflexible. Some Binaries have sub Binaries
(like Archive) and we had to create dummy buffers just to handle that. It is
also a bad fit for IRObjectFile where the Module wants to own the buffer too.
Keeping this ownership would make supporting IR inside native objects
particularly painful.
This patch focuses in lib/Object. If something elsewhere used to own an Binary,
now it also owns a MemoryBuffer.
This patch introduces a few new types.
* MemoryBufferRef. This is just a pair of StringRefs for the data and name.
This is to MemoryBuffer as StringRef is to std::string.
* OwningBinary. A combination of Binary and a MemoryBuffer. This is needed
for convenience functions that take a filename and return both the
buffer and the Binary using that buffer.
The C api now uses OwningBinary to avoid any change in semantics. I will start
a new thread to see if we want to change it and how.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216002 91177308-0d34-0410-b5e6-96231b3b80d8
Add header guards to files that were missing guards. Remove #endif comments
as they don't seem common in LLVM (we can easily add them back if we decide
they're useful)
Changes made by clang-tidy with minor tweaks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215558 91177308-0d34-0410-b5e6-96231b3b80d8
string_ostream is a safe and efficient string builder that combines opaque
stack storage with a built-in ostream interface.
small_string_ostream<bytes> additionally permits an explicit stack storage size
other than the default 128 bytes to be provided. Beyond that, storage is
transferred to the heap.
This convenient class can be used in most places an
std::string+raw_string_ostream pair or SmallString<>+raw_svector_ostream pair
would previously have been used, in order to guarantee consistent access
without byte truncation.
The patch also converts much of LLVM to use the new facility. These changes
include several probable bug fixes for truncated output, a programming error
that's no longer possible with the new interface.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211749 91177308-0d34-0410-b5e6-96231b3b80d8
Previous algorithm for constructing [Address ranges]->[Compile Units]
mapping was wrong. It somewhat relied on the assumption that address ranges
for different compile units may not overlap. It is not so.
For example, two compile units may contain the definition of the same
linkonce_odr function. These definitions will be merged at link-time,
resulting in equivalent .debug_ranges entries for both these units
Instead of sorting and merging original address ranges (from .debug_ranges
and .debug_aranges), implement a different approach: save endpoints
of all ranges, and then use a sweep-line approach to construct
the desired mapping. If we find that certain address maps to
several compilation units, we just pick any of them.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210860 91177308-0d34-0410-b5e6-96231b3b80d8
Turns out that DW_AT_ranges_base attribute sets the offset for
DW_AT_ranges values specified in the .dwo file, but not for DW_AT_ranges specified
in the skeleton compile unit DIE in the main executable. This is extremely confusing,
and would hopefully be fixed in DWARF-5 when it's finalized. For now this
behavior makes sense, as otherwise Fission would break DWARF consumers who
doesn't know anything about DW_AT_ranges_base.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210809 91177308-0d34-0410-b5e6-96231b3b80d8
Change --functions option in llvm-symbolizer tool to accept
values "none", "short" or "linkage". Update the tests and docs
accordingly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209050 91177308-0d34-0410-b5e6-96231b3b80d8
It is more appropriate than the current situation, when one flag
(AbsoluteFilePath) is relevant only if another flag is set.
This refactoring would also simplify fetching the short function name
(stored in DW_AT_name) instead of a linkage name returned currently.
No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208921 91177308-0d34-0410-b5e6-96231b3b80d8
Streamline parsing and dumping line tables:
Prefer composition to multiple inheritance in DWARFDebugLine::ParsingState.
Get rid of the weird concept of "DumpingState" structure.
was:
DWARFDebugLine::DumpingState state(OS);
DWARFDebugLine::parseStatementTable(..., state);
now:
DWARFDebugLine::LineTable LineTable;
LineTable.parse(...);
LineTable.dump(OS);
No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207599 91177308-0d34-0410-b5e6-96231b3b80d8
Move several function definitions into .cpp, unify constructors
and clear() methods (fixing a couple of latent bugs from copy-paste),
turn static function parsePrologue() into Prologue::parse().
More work needed here to untangle weird multiple inheritance
in table parsing and dumping.
No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207579 91177308-0d34-0410-b5e6-96231b3b80d8
DIE doesn't need to store a pointer to its parent: we can traverse the DIE tree
only with functions getFirstChild() and getSibling(). Parents must be known
only when we construct the tree. Rewrite setDIERelations() procedure in a more
straightforward way, and get rid of lots of now unused DIEMinimal methods.
No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207563 91177308-0d34-0410-b5e6-96231b3b80d8
FrameEntry doesn't need to hold a reference to the section it is
located in. Instead, pass DataExtractor as an argument of parsing
function.
No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207461 91177308-0d34-0410-b5e6-96231b3b80d8
There is no need to keep the whole contents of .debug_aranges section
in memory when we build address ranges table. Memory optimization that
used to be in this code (precalculate the size of vector of ranges before
filling it) is not really needed - later we will compact and resize this
vector anyway.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207457 91177308-0d34-0410-b5e6-96231b3b80d8
behavior based on other files defining DEBUG_TYPE, which means it cannot
define DEBUG_TYPE at all. This is actually better IMO as it forces folks
to define relevant DEBUG_TYPEs for their files. However, it requires all
files that currently use DEBUG(...) to define a DEBUG_TYPE if they don't
already. I've updated all such files in LLVM and will do the same for
other upstream projects.
This still leaves one important change in how LLVM uses the DEBUG_TYPE
macro going forward: we need to only define the macro *after* header
files have been #include-ed. Previously, this wasn't possible because
Debug.h required the macro to be pre-defined. This commit removes that.
By defining DEBUG_TYPE after the includes two things are fixed:
- Header files that need to provide a DEBUG_TYPE for some inline code
can do so by defining the macro before their inline code and undef-ing
it afterward so the macro does not escape.
- We no longer have rampant ODR violations due to including headers with
different DEBUG_TYPE definitions. This may be mostly an academic
violation today, but with modules these types of violations are easy
to check for and potentially very relevant.
Where necessary to suppor headers with DEBUG_TYPE, I have moved the
definitions below the includes in this commit. I plan to move the rest
of the DEBUG_TYPE macros in LLVM in subsequent commits; this one is big
enough.
The comments in Debug.h, which were hilariously out of date already,
have been updated to reflect the recommended practice going forward.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206822 91177308-0d34-0410-b5e6-96231b3b80d8
This is important for symbolizing executables with debug info in
unavailable .dwo files. Even if all DIE entries are missing, we can
still symbolize an address: function name can be fetched from symbol table,
and file/line info can be fetched from line table.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206665 91177308-0d34-0410-b5e6-96231b3b80d8
Immutable DILineInfo doesn't bring any benefits and complicates
code. Also, use std::string instead of SmallString<16> for file
and function names - their length can vary significantly.
No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206654 91177308-0d34-0410-b5e6-96231b3b80d8
When address ranges for compile unit are specified in compile unit DIE
itself, there is no need to collect ranges from children subprogram DIEs.
This change speeds up llvm-symbolizer on Clang-produced binaries with
full debug info. For instance, symbolizing a first address in a 1Gb binary
is now 2x faster (1s vs. 2s).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206641 91177308-0d34-0410-b5e6-96231b3b80d8