This reverts commit 0fbaf3a7 as tests
are failing on some bots.

Summary:
The AIX assembler .space directive can't take a second non-zero argument to fill
with. But LLVM emitFill currently assumes it can. We add a flag to the AsmInfo
to check if non-zero fill is supported, and if we can't zerofill non-zero values
we just splat the .byte directives.

Reviewers: stevewan, sfertile, DiggerLin, jasonliu, Xiangling_L

Reviewed By: jasonliu

Subscribers: Xiangling_L, wuzish, nemanjai, hiraditya, kbarton, jsji, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73554

This change has two components. The moves the generated file
for a namespace to the directory named after the namespace in
a file named 'index.<format>'. This greatly improves the browsing
experience since the index page is shown by default for a directory.

The second improves the markdown output by adding the links to the
referenced pages for children objects and the link back to the source
code.

Patch By: Clayton

Differential Revision: https://reviews.llvm.org/D72954

Preparation for adding support for tiling to parallel loops.

Differential Revision: https://reviews.llvm.org/D73872

LinalgDependenceGraph was not updated after successful producer-consumer
fusion for linalg ops. In this patch it is fixed by reconstructing
LinalgDependenceGraph on every iteration. This is very ineffective and
should be improved by updating LDGraph only when it is necessary.

Given

```
tb(n)z (and x, m), b
```

Where the `b`-th bit of `m` is 1,

```
tb(n)z (and x, m), b == tb(n)z x, b
```

So, we can walk past a `G_AND` in this case.

Also add test/CodeGen/AArch64/GlobalISel/opt-fold-and-tbz-tbnz.mir to test this.

Differential Revision: https://reviews.llvm.org/D73790

convertPtrAddToAdd improved overall code size and quality by a significant amount,
but on -O0 we generate some cross-class copies due to the fact that we emitted
G_PTRTOINT and G_INTTOPTR around the G_ADD. Unfortunately at -O0 we don't run any
register coalescing, so these cross class copies end up escaping as moves, and
we ended up regressing 3 benchmarks on CTMark (though still a winner overall).

This patch changes the lowering to instead directly emit the G_ADD into the
destination register, and then force changes the dest LLT to s64 from p0. This
should be ok, as all uses of the register should now be selected and therefore
the LLT doesn't matter for the users. It does however matter for the importer
patterns, which will fail to select a G_ADD if there's a p0 LLT.

I'm not able to get rid of the G_PTRTOINT on the source yet however. We can't
use the same trick of breaking the type system since that could break the
selection of the defining instruction. Thus with -O0 we still end up with a
cross class copy on source.

Code size improvements on -O0:
Program                                         baseline      new         diff
 test-suite :: CTMark/Bullet/bullet.test        965520       949164      -1.7%
 test-suite...TMark/7zip/7zip-benchmark.test    1069456      1052600     -1.6%
 test-suite...ark/tramp3d-v4/tramp3d-v4.test    1213692      1199804     -1.1%
 test-suite...:: CTMark/sqlite3/sqlite3.test    421680       419736      -0.5%
 test-suite...-typeset/consumer-typeset.test    837076       833380      -0.4%
 test-suite :: CTMark/lencod/lencod.test        799712       796976      -0.3%
 test-suite...:: CTMark/ClamAV/clamscan.test    688264       686132      -0.3%
 test-suite :: CTMark/kimwitu++/kc.test         1002344      999648      -0.3%
 test-suite...Mark/mafft/pairlocalalign.test    422296       421768      -0.1%
 test-suite :: CTMark/SPASS/SPASS.test          656792       656532      -0.0%
 Geomean difference                                                      -0.6%

Differential Revision: https://reviews.llvm.org/D73910

Start using a new strategy with a combination of merge and unmerges.

This allows scalarizing before lowering, which in cases like
<2 x s128> avoids producing giant illegal shifts.

RegAllocGreedy uses a fairly compile time intensive splitting heuristic
called region splitting. This heuristic was disabled via another heuristic
when it is likely that it won't be worth the compile time. The only way
to control this other heuristic was via a command line option (huge-size-for-split).

This commit gives more control on this heuristic by making it overridable
by the target using a target hook in TargetRegisterInfo called
shouldRegionSplitForVirtReg.

The default implementation of this hook keeps the heuristic as it was
before this patch.

```
src/UnwindCursor.hpp:1344:51: error: operator '?:' has lower precedence than '|';
    '|' will be evaluated first [-Werror,-Wbitwise-conditional-parentheses]
  _info.flags = isSingleWordEHT ? 1 : 0 | scope32 ? 0x2 : 0;  // Use enum?
                                      ~~~~~~~~~~~ ^
src/UnwindCursor.hpp:1344:51: note: place parentheses around the '|' expression
    to silence this warning
  _info.flags = isSingleWordEHT ? 1 : 0 | scope32 ? 0x2 : 0;  // Use enum?
                                                  ^
                                      (          )
src/UnwindCursor.hpp:1344:51: note: place parentheses around the '?:' expression
    to evaluate it first
  _info.flags = isSingleWordEHT ? 1 : 0 | scope32 ? 0x2 : 0;  // Use enum?
                                                  ^
                                          (                )
```

But `0 |` is a no-op for either of those two interpretati...

ClangBuildAnalyzer results show that a lot of time is spent
instantiating AnalysisManager::getResultImpl across the code base:

**** Templates that took longest to instantiate:
 50445 ms: llvm::AnalysisManager<llvm::Function>::getResultImpl (412 times, avg 122 ms)
 47797 ms: llvm::AnalysisManager<llvm::Function>::getResult<llvm::TargetLibraryAnalysis> (389 times, avg 122 ms)
 46894 ms: std::tie<const unsigned long long, const bool> (2452 times, avg 19 ms)
 43851 ms: llvm::BumpPtrAllocatorImpl<llvm::MallocAllocator, 4096, 4096>::Allocate (3228 times, avg 13 ms)
 33911 ms: std::tie<const unsigned int, const unsigned int, const unsigned int, const unsigned int> (897 times, avg 37 ms)
 33854 ms: std::tie<const unsigned long long, const unsigned long long> (1897 times, avg 17 ms)
 27886 ms: std::basic_string<char, std::char_traits<char>, std::allocator<char> >::basic_string (11156 times, avg 2 ms)

I mentioned this result to @chandlerc, and he suggested this direction.

AnalysisManager is already explicitly instantiated, and getResultImpl
doesn't need to be inlined. Move the definition to an Impl header, and
include that header in files that explicitly instantiate
AnalysisManager. There are only four (real) IR units:
- function
- module
- loop
- cgscc

Looking at a specific transform (ArgumentPromotion.cpp), here are three
compilations before & after this change:

BEFORE:
$ for i in $(seq 3) ; do ./ccit.bat ; done
peak memory: 258.15MB
real: 0m6.297s
peak memory: 257.54MB
real: 0m5.906s
peak memory: 257.47MB
real: 0m6.219s

AFTER:
$ for i in $(seq 3) ; do ./ccit.bat ; done
peak memory: 235.35MB
real: 0m5.454s
peak memory: 234.72MB
real: 0m5.235s
peak memory: 234.39MB
real: 0m5.469s

The 20MB of memory saved seems real, and the time improvement seems like
it is there.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D73817

This reverts commit 31574d38.

The newly added shufflevector test does not pass locally on either of my
workstations.

Summary:
llvm-objdump started warning when asked to disassemble a section that
isn't present in the input files, in Yuanfang Chen's change:
d16c162c. The problem is that the
logic was restricted only to the generic llvm-objdump parser, not to the
Mach-O-specific parser used for Apple toolchain compatibility. The
solution is to log section names from the Mach-O parser.

The macho-cstring-dump.test has been updated to fail if it encounters
this new warning in the future.

Reviewers: pete, ab, lhames, jhenderson, grimar, MaskRay, ychen

Reviewed By: jhenderson, grimar

Subscribers: rupprecht, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73586

I previously removed the code in ValueObject::GetExpressionPath that
took advantage of the parameter `qualify_cxx_base_classes`. As a result,
this is now unused and can be removed.

Summary:
I think that there are very few things from clang that actually need forward
declaration, so not having a ClangForward header makes sense.

Differential Revision: https://reviews.llvm.org/D73827

The regex can be extended if needed, but this should probably handle
most of the cases.

Differential Revision: https://reviews.llvm.org/D73852

Summary:
Method appendLoopsToWorklist is duplicate in LoopUnroll and in the
LoopPassManager as an internal method. Make it an utility.

Reviewers: dmgreen, chandlerc, fedor.sergeev, yamauchi

Subscribers: mehdi_amini, hiraditya, zzheng, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73569

Summary:
* Most of the simplifications in SimplifyShuffleVectorInst depend on the
concrete value of, or the length of the mask vector. For scalable
vectors, this cannot be known at compile time.
** for these tests, detect if the vector is scalable before attempting
the transformation
* The functions ShuffleVectorInst::getMaskValue and
ShuffleVectorInst::getShuffleMask access the value of the constant mask.
However, since the length of the mask is unknown at compile time, these
function do not work for scalable vectors. Add asserts to ensure that
the input mask is not scalable

Reviewers: efriedma, sdesmalen, apazos, chrisj, huihuiz

Reviewed By: efriedma

Subscribers: tschuett, hiraditya, rkruppe, psnobl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73555

isLocallyOpenedFile() does not use IRBuilder.

Split out from D73835. This method was added to ConstantFolder and
TargetFolder, but not NoFolder.

This reverts commit 789a46f2.

Accidentally committed.

Split out from D73835: These methods are not part of the
ConstantFolder API and as such don't serve a purpose.

Adds a replaceOperand() helper, which is like Instruction.setOperand()
but adds the old operand to the worklist. This reduces the amount of
missing or incorrect worklist management.

This only applies the helper to a relatively small subset of
setOperand() calls in InstCombine, namely those of the pattern
`I.setOperand(); return &I;`, where it is most obviously applicable.

Differential Revision: https://reviews.llvm.org/D73803

This renames Worklist.AddDeferred() to Worklist.add() and
Worklist.Add() to Worklist.push(). The intention here is that
Worklist.add() should be the go-to method for explicit worklist
management, while the raw Worklist.push() is mostly for
InstCombine internals. I will then migrate uses of Worklist.push()
to Worklist.add() in followup changes.

As suggested by spatel on D73411 I'm also changing the remaining
method names to lowercase first character, in line with current
coding standards.

Differential Revision: https://reviews.llvm.org/D73745

Summary:
Clang -fpic defaults to -fno-semantic-interposition (GCC -fpic defaults
to -fsemantic-interposition).
Users need to specify -fsemantic-interposition to get semantic
interposition behavior.

Semantic interposition is currently a best-effort feature. There may
still be some cases where it is not handled well.

Reviewers: peter.smith, rnk, serge-sans-paille, sfertile, jfb, jdoerfert

Subscribers: dschuff, jyknight, dylanmckay, nemanjai, jvesely, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, arphaman, PkmX, jocewei, jsji, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D73865

Followup to D73135. If the target doesn't have hard float (default
for ARM), then we assert when trying to soften the result of vector
reduction intrinsics. This patch marks these for expansion as well.
(A bit odd to use vectors on a target without hard float ... but
that's where you end up if you expose target-independent vector types.)

Differential Revision: https://reviews.llvm.org/D73854

D72486 broke the shared library build.

Emit llvm parallel access metadata for the loops if they are marked as
order(concurrent).

Summary:
A recent change to enable more importing of global variables with
references exposed some efficiency issues with export computation.
See D73724 for more information and detailed analysis.

The first was specific to variable importing. The code was marking every
copy of a referenced value (from possibly thousands of files in the case
of linkonce_odr) as exported, and we only need to mark the copy in the
module containing the variable def being imported as exported. The
reason is that this is tracking what values are newly exported as a
result of importing. Anything that was defined in another module and
simply used in the exporting module is already exported, and would have
been identified by the caller (e.g. the LTO API implementations).

The second issue is that the code was re-adding previously exported
values (along with all references). It is easy to identify when a
variable was already imported into the same module (via the
import list insert call return value), and we already did this for
function importing. However, what we weren't doing for either function
or variable importing was avoiding a re-insertion when it was previously
exported into a different importing module. The reason we couldn't do
this is there was no way of telling from the export list whether it was
previously inserted there because its definition was exported (in which
case we already marked all its references as exported) from when it was
inserted there because it was referenced by another exported value (in
which case we haven't yet inserted its own references).

To address this we can restructure the way the export list is
constructed. This patch only adds the actual imported definitions
(variable or function) to the export list for its module during the
import computation. After import computation is complete, where we were
already post-processing the export list we go ahead and add all
references made by those exported values to the export list.

These changes speed up the thin link not only with constant variable
importing enabled, but also without (due to the efficiency improvement
in function importing).

Some thin link user time measurements for one large application, average
of 5 runs:

With constant variable importing enabled:
- without this patch: 479.5s
- with this patch: 74.6s

Without constant variable importing enabled:
- without this patch: 80.6s
- with this patch: 70.3s

Note I have not re-enabled constant variable importing here, as I would
like to do additional compile time measurements with these fixes first.

Reviewers: evgeny777

Subscribers: mehdi_amini, inglorion, hiraditya, dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73851

Summary:
This prevents unwanted clustering of BUF instructions with the same
vaddr but different resource descriptors.

Reviewers: rampitec, arsenm, nhaehnle

Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73867

As detailed on PR43463, this fixes a static analyzer null dereference warning by sinking Changed = true into the if() blocks where the MIB is actually created.

I did a quick check that suggested that one of those if() blocks is always guaranteed to be hit (so we could change it to if-else), but this seems like a safer approach

Differential Revision: https://reviews.llvm.org/D73883

We have to be careful in SimplifyDemandedBits with loads in case we attempt to combine back to a constant (which then gets turned into a constant pool load again), but we can at least set the upper KnownBits for a ZEXTLoad to zero.

The fix in b3d7d106 compiled nicely,
but didn't link because at least the VS 2017 version I use doesn't
have the builtin yet. Instead, make use of the builtin with MSVC
conditional on VS 2019 or later.

Summary:
- Fail loudly if SetFocusFunction failed when it should not. For more info see
  - https://github.com/google/oss-fuzz/issues/3311
  - https://github.com/google/sanitizers/issues/1190
- Fail loudly if CollectDataFlow is called without seed corpus.

Reviewers: kcc, metzman

Subscribers: #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D73813

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: arsenm, dschuff, jyknight, sdardis, nemanjai, jvesely, nhaehnle, sbc100, jgravelle-google, hiraditya, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73885