Commit Graph

5106 Commits

Author SHA1 Message Date
Guillaume Chatelet d1f23bd225 Revert "[Alignment][NFC] Allow constexpr Align"
This reverts commit b3af236fb5.

llvm-svn: 373619
2019-10-03 15:53:50 +00:00
Sander de Smalen 4f99b6f0fe [AArch64] Static (de)allocation of SVE stack objects.
Adds support to AArch64FrameLowering to allocate fixed-stack SVE objects.

The focus of this patch is purely to allow the stack frame to
allocate/deallocate space for scalable SVE objects. More dynamic
allocation (at compile-time, i.e. determining placement of SVE objects
on the stack), or resolving frame-index references that include
scalable-sized offsets, are left for subsequent patches.

SVE objects are allocated in the stack frame as a separate region below
the callee-save area, and above the alignment gap. This is done so that
the SVE objects can be accessed directly from the FP at (runtime)
VL-based offsets to benefit from using the VL-scaled addressing modes.

The layout looks as follows:

     +-------------+
     | stack arg   |   
     +-------------+
     | Callee Saves|
     |   X29, X30  |       (if available)
     |-------------| <- FP (if available)
     |     :       |   
     |  SVE area   |   
     |     :       |   
     +-------------+
     |/////////////| alignment gap.
     |     :       |   
     | Stack objs  |
     |     :       |   
     +-------------+ <- SP after call and frame-setup

SVE and non-SVE stack objects are distinguished using different
StackIDs. The offsets for objects with TargetStackID::SVEVector should be
interpreted as purely scalable offsets within their respective SVE region.

Reviewers: thegameg, rovka, t.p.northover, efriedma, rengolin, greened

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D61437

llvm-svn: 373585
2019-10-03 11:33:50 +00:00
Kristina Brooks 43817e1915 Revert 373551 (CodeExpander.cpp CMake issue)
Fix buildbots and revert the CodeExpander commit.

(See http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20190930/699857.html )

llvm-svn: 373581
2019-10-03 11:04:48 +00:00
Guillaume Chatelet b3af236fb5 [Alignment][NFC] Allow constexpr Align
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68329

llvm-svn: 373580
2019-10-03 10:53:10 +00:00
Kristina Brooks abc35f1bd8 Revert 373555: libLLVM+modules failure with CMake 3.10.2
This reverts rL373555. I've sent an email out regarding the issue.

Commit on GitHub:
45f682f471

llvm-svn: 373579
2019-10-03 10:48:37 +00:00
Daniel Sanders 45f682f471 [gicombiner] Make rL373551 compatible with older cmakes
Newer cmakes appear to be more flexible w.r.t object libraries. Convert to
a static library so that it works with older cmakes too

llvm-svn: 373555
2019-10-03 01:49:04 +00:00
Daniel Sanders eb27b5de53 [gicombiner] Add a CodeExpander to handle C++ fragments with variable expansion
Summary:
This will handle expansion of C++ fragments in the declarative combiner
including custom predicates, and escapes into C++ to aid the migration
effort.

Reviewers: bogner, volkan

Subscribers: mgorny, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68288

llvm-svn: 373551
2019-10-03 01:04:42 +00:00
Florian Hahn a80b6c1542 [Local] Handle terminators with users in removeUnreachableBlocks.
Terminators like invoke can have users outside the current basic block.
We have to replace those users with undef, before replacing the
terminator.

This fixes a crash exposed by rL373430.

Reviewers: brzycki, asbirlea, davide, spatel

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D68327

llvm-svn: 373513
2019-10-02 19:38:24 +00:00
Florian Hahn eb6700b57e [Local] Remove unused LazyValueInfo pointer from removeUnreachableBlock.
There are no users that pass in LazyValueInfo, so we can simplify the
function a bit.

Reviewers: brzycki, asbirlea, davide

Reviewed By: davide

Differential Revision: https://reviews.llvm.org/D68297

llvm-svn: 373488
2019-10-02 16:58:13 +00:00
Thomas Preud'homme ed1178689f [FileCheck] Move private interface to its own header
Summary:
Most of the class definition in llvm/include/llvm/Support/FileCheck.h
are actually implementation details that should not be relied upon. This
commit moves all of it in a new header file under
llvm/lib/Support/FileCheck. It also takes advantage of the code movement
to put the code into a new llvm::filecheck namespace.

Reviewers: jhenderson, chandlerc, jdenny, probinson, grimar, arichardson, rnk

Subscribers: hiraditya, llvm-commits, probinson, dblaikie, grimar, arichardson, tra, rnk, kristina, hfinkel, rogfer01, JonChesterfield

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67649

llvm-svn: 373395
2019-10-01 21:37:55 +00:00
Clement Courbet 8109901bf6 [llvm-exegesis][NFC] Refactor X86 tests fixtures into a base class.
Reviewers: gchatelet, a.sidorin

Subscribers: tschuett, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68262

llvm-svn: 373313
2019-10-01 09:20:36 +00:00
Yuanfang Chen cc382cf727 [NewPM] Port MachineModuleInfo to the new pass manager.
Existing clients are converted to use MachineModuleInfoWrapperPass. The
new interface is for defining a new pass manager API in CodeGen.

Reviewers: fedor.sergeev, philip.pfaffe, chandlerc, arsenm

Reviewed By: arsenm, fedor.sergeev

Differential Revision: https://reviews.llvm.org/D64183

llvm-svn: 373240
2019-09-30 17:54:50 +00:00
Thomas Preud'homme 02ada9bd2b [FileCheck] Remove implementation types from API
Summary:
Remove use of FileCheckPatternContext and FileCheckString concrete types
from FileCheck API to allow moving it and the other implementation only
only declarations into a private header file.

Reviewers: jhenderson, chandlerc, jdenny, probinson, grimar, arichardson, rnk

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68186

llvm-svn: 373211
2019-09-30 14:12:03 +00:00
Chen Zheng bfec045626 [ConstantRange] add helper function addWithNoWrap().
Differential Revision: https://reviews.llvm.org/D67339

llvm-svn: 373205
2019-09-30 12:57:53 +00:00
Clement Courbet 3e13816be2 [llvm-exegesis][NFC] Refactor snippet file reading out of tool main.
Summary: Add unit tests.

Reviewers: gchatelet

Subscribers: mgorny, tschuett, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68212

llvm-svn: 373202
2019-09-30 12:50:25 +00:00
Guillaume Chatelet 02c19658ff [Alignment][NFC] Adding a max function.
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68201

llvm-svn: 373196
2019-09-30 09:59:31 +00:00
Roman Lebedev 8c39d01670 [PatternMatch] Add m_SExtOrSelf(), m_ZExtOrSExtOrSelf() matchers + unittests
m_SExtOrSelf() is for consistency.

m_ZExtOrSExtOrSelf() is motivated by the D68103/r373106 :
sometimes it is useful to look past any extensions of the shift amount,
and m_ZExtOrSExtOrSelf() may be exactly the tool to do that.

llvm-svn: 373128
2019-09-27 21:53:04 +00:00
Clement Courbet 24078fe157 [llvm-exegesis] Fix r373083: Module -> Mod.
SnippetRepetitorTest.cpp:66:27: error: declaration of ‘std::unique_ptr<llvm::Module> llvm::exegesis::{anonymous}::X86SnippetRepetitorTest::Module’ [-fpermissive]
   std::unique_ptr<Module> Module;

llvm-svn: 373087
2019-09-27 13:21:37 +00:00
Clement Courbet 9431b72ce9 [llvm-exegesis] Add loop mode for repeating the snippet.
Summary:
Before this change the Executable function was made by duplicating the
snippet. This change adds a --repetion-mode={loop|duplicate} flag that
allows choosing between this behaviour and wrapping the snippet instructions
in a loop.

The new mode can help measurements when the snippet fits in the DSB by
short-cirtcuiting decoding. The loop adds a dec + jmp to the measurements, but
since these are not part of the critical path, they execute in parallel
with the measured code and do not impact measurements in practice.

Overview of the change:
 - New SnippetRepetitor abstraction that handles repeating the snippet.
   The assembler delegates repeating the instructions to this class.
 - ExegesisTarget learns how to decrement loop counter and jump.
 - Some refactoring of the assembler into FunctionFiller/BasicBlockFiller.

Reviewers: gchatelet

Subscribers: mgorny, tschuett, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68125

llvm-svn: 373083
2019-09-27 12:56:24 +00:00
Clement Courbet 8ef97e1aad [llvm-exegesis] Refactor how forbidden registers are computed.
Summary:
Right now latency generation can incorrectly select the scratch register
as a dependency-carrying register.
 - Move the logic for preventing register selection from Uops
   implementation to common SnippetGenerator class.
 - Aliasing detection now takes a set of forbidden registers just like
   random register assignment does.

Reviewers: gchatelet

Subscribers: tschuett, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68084

llvm-svn: 373048
2019-09-27 08:04:10 +00:00
Whitney Tsang 9c5fbcf920 [LOOPGUARD] Disable loop with multiple loop exiting blocks.
Summary: As discussed in the loop group meeting. With the current
definition of loop guard, we should not allow multiple loop exiting
blocks. For loops that has multiple loop exiting blocks, we can simply
unable to find the loop guard.
When getUniqueExitBlock() obtains a vector size not equals to one, that
means there is either no exit blocks or there exists more than one
unique block the loop exit to.
If we don't disallow loop with multiple loop exit blocks, then with our
current implementation, there can exist exit blocks don't post dominated
by the non pre-header successor of the guard block.
Reviewer: reames, Meinersbur, kbarton, etiotto, bmahjour
Reviewed By: Meinersbur, kbarton
Subscribers: fhahn, hiraditya, llvm-commits
Tag: LLVM
Differential Revision: https://reviews.llvm.org/D66529

llvm-svn: 373011
2019-09-26 20:20:42 +00:00
Matt Arsenault df3af00421 Fix typo
llvm-svn: 372988
2019-09-26 15:20:16 +00:00
Huihui Zhang 4de7ae6532 [NFC] Add { } to silence compiler warning [-Wmissing-braces].
llvm-project/llvm/unittests/ADT/ArrayRefTest.cpp:254:25: warning: suggest braces around initialization of subobject [-Wmissing-braces]
  std::array<int, 5> A1{42, -5, 0, 1000000, -1000000};
                        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
                        {                           }

llvm-svn: 372902
2019-09-25 17:32:20 +00:00
Florian Hahn 5c3bc3c930 [PatternMatch] Make m_Br more flexible, add matchers for BB values.
Currently m_Br only takes references to BasicBlock*, which limits its
flexibility. For example, you have to declare a variable, even if you
ignore the result or you have to have additional checks to make sure the
matched BB matches an expected one.

This patch adds m_BasicBlock and m_SpecificBB matchers, which can be
used like the existing matchers for constants or values.

I also had a look at the existing uses and updated a few. IMO it makes
the code a bit more explicit.

Reviewers: spatel, craig.topper, RKSimon, majnemer, lebedev.ri

Reviewed By: lebedev.ri

Differential Revision: https://reviews.llvm.org/D68013

llvm-svn: 372885
2019-09-25 15:05:08 +00:00
Sanjay Patel 6d4ea22e70 [IR] allow fast-math-flags on phi of FP values (2nd try)
The changes here are based on the corresponding diffs for allowing FMF on 'select':
D61917 <https://reviews.llvm.org/D61917>

As discussed there, we want to have fast-math-flags be a property of an FP value
because the alternative (having them on things like fcmp) leads to logical
inconsistency such as:
https://bugs.llvm.org/show_bug.cgi?id=38086

The earlier patch for select made almost no practical difference because most
unoptimized conditional code begins life as a phi (based on what I see in clang).
Similarly, I don't expect this patch to do much on its own either because
SimplifyCFG promptly drops the flags when converting to select on a minimal
example like:
https://bugs.llvm.org/show_bug.cgi?id=39535

But once we have this plumbing in place, we should be able to wire up the FMF
propagation and start solving cases like that.

The change to RecurrenceDescriptor::AddReductionVar() is required to prevent a
regression in a LoopVectorize test. We are intersecting the FMF of any
FPMathOperator there, so if a phi is not properly annotated, new math
instructions may not be either. Once we fix the propagation in SimplifyCFG, it
may be safe to remove that hack.

Differential Revision: https://reviews.llvm.org/D67564

llvm-svn: 372878
2019-09-25 14:35:02 +00:00
Sanjay Patel 2cec4b58f5 Revert [IR] allow fast-math-flags on phi of FP values
This reverts r372866 (git commit dec03223a9)

llvm-svn: 372868
2019-09-25 13:29:09 +00:00
Sanjay Patel dec03223a9 [IR] allow fast-math-flags on phi of FP values
The changes here are based on the corresponding diffs for allowing FMF on 'select':
D61917

As discussed there, we want to have fast-math-flags be a property of an FP value
because the alternative (having them on things like fcmp) leads to logical
inconsistency such as:
https://bugs.llvm.org/show_bug.cgi?id=38086

The earlier patch for select made almost no practical difference because most
unoptimized conditional code begins life as a phi (based on what I see in clang).
Similarly, I don't expect this patch to do much on its own either because
SimplifyCFG promptly drops the flags when converting to select on a minimal
example like:
https://bugs.llvm.org/show_bug.cgi?id=39535

But once we have this plumbing in place, we should be able to wire up the FMF
propagation and start solving cases like that.

The change to RecurrenceDescriptor::AddReductionVar() is required to prevent a
regression in a LoopVectorize test. We are intersecting the FMF of any
FPMathOperator there, so if a phi is not properly annotated, new math
instructions may not be either. Once we fix the propagation in SimplifyCFG, it
may be safe to remove that hack.

Differential Revision: https://reviews.llvm.org/D67564

llvm-svn: 372866
2019-09-25 13:14:12 +00:00
Fangrui Song 2bc478844a [ADT] Add StringMap::insert_or_assign
Summary: Similar to std::unordered_map::insert_or_assign

Reviewers: alexshap, bkramer, dblaikie, lhames

Subscribers: jkorous, dexonsmith, kristina, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67668

llvm-svn: 372813
2019-09-25 04:58:02 +00:00
Artur Pilipenko 5c1447cd43 [SCEV] Disable canonical expansion for non-affine addrecs.
Reviewed By: apilipenko

Differential Revision: https://reviews.llvm.org/D65276

Patch by Evgeniy Brevnov (ybrevnov@azul.com)

llvm-svn: 372789
2019-09-24 23:21:07 +00:00
Hiroshi Yamauchi 857424d185 [PGO][PGSO] ProfileSummary changes.
(Split of off D67120)

ProfileSummary changes for profile guided size optimization.

Differential Revision: https://reviews.llvm.org/D67377

llvm-svn: 372783
2019-09-24 22:17:51 +00:00
Cyndy Ishida d8d99d957c [TextAPI] Add New Supported Platforms
Summary: This patch introduces simulators, as well was the restriced zippered and macCatalyst to supported platforms

Reviewers: ributzka, steven_wu

Reviewed By: ributzka

Subscribers: hiraditya, dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67528

llvm-svn: 372618
2019-09-23 15:28:02 +00:00
Cyndy Ishida 81669d5ead [TextAPI] Arch&Platform to Target
Summary:
This is a patch for updating TextAPI/Macho to read in targets as opposed to arch/platform.
This is because in previous versions tbd files only supported a single platform but that is no longer the case,
so, now its tracked by unique triples.
This precedes a seperate patch that will add  the TBD-v4 format

Reviewers: ributzka, steven_wu, plotfi, compnerd, smeenai

Reviewed By: ributzka

Subscribers: mgorny, hiraditya, dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67527

llvm-svn: 372396
2019-09-20 14:32:34 +00:00
David Tellenbach 2a47c77e72 [FastISel] Fix insertion of unconditional branches during FastISel
The insertion of an unconditional branch during FastISel can differ depending on
building with or without debug information. This happens because FastISel::fastEmitBranch
emits an unconditional branch depending on the size of the current basic block
without distinguishing between debug and non-debug instructions.

This patch fixes this issue by ignoring debug instructions when getting the size
of the basic block.

Reviewers: aprantl

Reviewed By: aprantl

Subscribers: ormris, aprantl, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67703

llvm-svn: 372389
2019-09-20 13:22:59 +00:00
Francesco Petrogalli cb032aa2c7 [SVFS] Vector Function ABI demangling.
This patch implements the demangling functionality as described in the
Vector Function ABI. This patch will be used to implement the
SearchVectorFunctionSystem (SVFS) as described in the RFC:

http://lists.llvm.org/pipermail/llvm-dev/2019-June/133484.html

A fuzzer is added to test the demangling utility.

Patch by Sumedh Arani <sumedh.arani@arm.com>

Differential revision: https://reviews.llvm.org/D66024

llvm-svn: 372343
2019-09-19 17:47:32 +00:00
Amy Huang 68eae49859 Add AutoUpgrade function to add new address space datalayout string to existing datalayouts.
Summary:
Add function to AutoUpgrade to change the datalayout of old X86 datalayout strings.
This adds "-p270:32:32-p271:32:32-p272:64:64" to X86 datalayouts that are otherwise valid
and don't already contain it.

This also removes the compatibility changes in https://reviews.llvm.org/D66843.
Datalayout change in https://reviews.llvm.org/D64931.

Reviewers: rnk, echristo

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67631

llvm-svn: 372267
2019-09-18 22:15:58 +00:00
Daniel Sanders 1723364a68 Fix compile-time regression caused by rL371928
Summary:
Also fixup rL371928 for cases that occur on our out-of-tree backend

There were still quite a few intermediate APInts and this caused the
compile time of MCCodeEmitter for our target to jump from 16s up to
~5m40s. This patch, brings it back down to ~17s by eliminating pretty
much all of them using two new APInt functions (extractBitsAsZExtValue(),
insertBits() but with a uint64_t). The exact conditions for eliminating
them is that the field extracted/inserted must be <=64-bit which is
almost always true.

Note: The two new APInt API's assume that APInt::WordSize is at least
64-bit because that means they touch at most 2 APInt words. They
statically assert that's true. It seems very unlikely that someone
is patching it to be smaller so this should be fine.

Reviewers: jmolloy

Reviewed By: jmolloy

Subscribers: hiraditya, dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67686

llvm-svn: 372243
2019-09-18 18:14:42 +00:00
Guillaume Chatelet ef8ef1278a [Alignment] Add a None() member function
Summary:
This will allow writing `if(A != llvm::Align::None())` which is clearer than `if(A > llvm::Align(1))`

This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67697

llvm-svn: 372207
2019-09-18 09:24:40 +00:00
Greg Clayton f71ececda2 Fix buildbots.
MSVC doesn't correctly capture constexpr in lambdas, and other builds warn if you do, others will error out if you do. Avoid lambdas.

llvm-svn: 372179
2019-09-17 20:31:01 +00:00
Greg Clayton c6b156cbb8 GSYM: Add the llvm::gsym::Header header class with tests
This patch adds the llvm::gsym::Header class which appears at the start of a stand alone GSYM file, or in the first bytes of the GSYM data in a GSYM section within a file. Added encode and decode methods with full error handling and full tests.

Differential Revision: https://reviews.llvm.org/D67666

llvm-svn: 372149
2019-09-17 17:46:13 +00:00
Simon Pilgrim 08a448fcbd Fix MSVC lambda capture warnings. NFCI.
llvm-svn: 372144
2019-09-17 17:24:55 +00:00
Greg Clayton b52650d57f GSYM: add encoding and decoding to FunctionInfo
This patch adds encoding and decoding of the FunctionInfo objects along with full error handling and tests. Full details of the FunctionInfo encoding format appear in the FunctionInfo.h header file.

Differential Revision: https://reviews.llvm.org/D67506

llvm-svn: 372135
2019-09-17 16:15:49 +00:00
Sam Parker 26a475afe5 [ARM][MVE] Add invalidForTailPredication to TSFlags
Set this bit for the MVE reduction instructions to prevent a loop from
becoming tail predicated in their presence.

Differential Revision: https://reviews.llvm.org/D67444

llvm-svn: 372076
2019-09-17 07:43:04 +00:00
Francis Visoiu Mistrih 77383d83eb [Remarks] Allow remarks::Format::YAML to take a string table
It should be allowed to take a string table in case all the strings in
the remarks point there, but it shouldn't use it during serialization.

llvm-svn: 372042
2019-09-16 22:45:17 +00:00
Francis Visoiu Mistrih d38f63e5f4 [Remarks][NFC] Forward declare ParsedStringTable
llvm-svn: 371870
2019-09-13 17:27:28 +00:00
George Rimar 8501102727 [yaml2obj/ObjectYAML] - Cleanup the error reporting API, add custom errors handlers.
This is a continuation of the YAML library error reporting
refactoring/improvement and the idea by itself was mentioned
in the following thread:
https://reviews.llvm.org/D67182?id=218714#inline-603404

This performs a cleanup of all object emitters in the library.
It allows using the custom one provided by the caller.

One of the nice things is that each tool can now print its tool name,
e.g: "yaml2obj: error: <text>"

Also, the code became a bit simpler.

Differential revision: https://reviews.llvm.org/D67445

llvm-svn: 371865
2019-09-13 16:00:16 +00:00
Benjamin Kramer ce74c3b19f [Orc] Address the remaining move-capture FIXMEs
This required spreading unique_function a bit more, which I think is a
good thing.

llvm-svn: 371843
2019-09-13 11:35:33 +00:00
David Blaikie ffe5466c79 Add some missing changes to GSYM that was addressing a gcc compilation error due to a type and variable with the same name
llvm-svn: 371681
2019-09-11 22:24:45 +00:00
Greg Clayton 7fcc2c2b5a Add a LineTable class to GSYM and test it.
This patch adds the ability to create a gsym::LineTable object, populate it, encode and decode it and test all functionality.

The full format of the LineTable encoding is specified in the header file LineTable.h.

Differential Revision: https://reviews.llvm.org/D66602

llvm-svn: 371657
2019-09-11 20:51:03 +00:00
Igor Kudrin bc48588f76 Reland [DWARF] Add a unit test for DWARFUnit::getLength().
This is a follow-up of rL369529, where the return value of
DWARFUnit::getLength() was changed from uint32_t to uint64_t.
The test checks that a unit header with Length > 4G can be successfully
parsed and the value of the Length field is not truncated.

Differential Revision: https://reviews.llvm.org/D67276

llvm-svn: 371510
2019-09-10 11:54:32 +00:00
Igor Kudrin c27af19280 Revert "[DWARF] Add a unit test for DWARFUnit::getLength()" because it broke ASAN bot.
llvm-svn: 371505
2019-09-10 10:17:48 +00:00