Summary:
This patch extends the DISubrange 'count' field to take either a
(signed) constant integer value or a reference to a DILocalVariable
or DIGlobalVariable.

This is patch [1/3] in a series to extend LLVM's DISubrange Metadata
node to support debugging of C99 variable length arrays and vectors with
runtime length like the Scalable Vector Extension for AArch64. It is
also a first step towards representing more complex cases like arrays
in Fortran.

Reviewers: echristo, pcc, aprantl, dexonsmith, clayborg, kristof.beyls, dblaikie

Reviewed By: aprantl

Subscribers: rnk, probinson, fhahn, aemerson, rengolin, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D41695

llvm-svn: 323313

For the included test case, the DAG transformation
  concat_vectors(scalar, undef) -> scalar_to_vector(sclr)
would attempt to create a v2i32 vector for a v9i8
concat_vector.  Bail out to avoid creating a bitcast with
mismatching sizes later on.

Differential Revision: https://reviews.llvm.org/D42379

llvm-svn: 323312

Summary:
This is the first attempt to write down a guideline on adding exception handling support for a target. The content basically bases on the discussion on [1]. If you guys know who is exception handling expert, please add him as the reviewer. Thanks.

[1] http://lists.llvm.org/pipermail/llvm-dev/2018-January/120405.html

Reviewers: t.p.northover, theraven, nemanjai

Reviewed By: theraven

Subscribers: sdardis, llvm-commits

Differential Revision: https://reviews.llvm.org/D42178

llvm-svn: 323311

Summary:
The new test is now in the right directory with the other ASTVisitor tests and uses
now the provided TestVisitor framework.

Subscribers: hintonda, v.g.vassilev, klimek, cfe-commits, mgorny

Differential Revision: https://reviews.llvm.org/D37557

llvm-svn: 323310

This patch removes assert that SCEV is able to prove that a value is
non-negative. In fact, SCEV can sometimes be unable to do this because
its cache does not update properly. This assert will be returned once this
problem is resolved.

llvm-svn: 323309

This matches what MSVC does for alloca() function calls on ARM.
Even if MSVC doesn't support VLAs at the language level, it does
support the alloca function.

On the clang level, both the _alloca() (when emulating MSVC, which is
what the alloca() function expands to) and __builtin_alloca() builtin
functions, and VLAs, map to the same LLVM IR "alloca" function - so
within LLVM they're not distinguishable from each other.

Differential Revision: https://reviews.llvm.org/D42292

llvm-svn: 323308

Merging such globals loses the dllexport attribute. Add a test
to check that normal globals still are merged.

Differential Revision: https://reviews.llvm.org/D42127

llvm-svn: 323307

llvm-svn: 323306

I think these instructions used to be named differently and the regular expression reflected that. I guess we must have correct itinerary information that made this not matter for the scheduler test?

llvm-svn: 323305

[X86] Rename 256-bit VFRCZ instructions to have the Y before the rr/rm to match other instructions. NFC

llvm-svn: 323304

llvm-svn: 323303

"the the" -> "the"

llvm-svn: 323302

There are a couple tricky things with this patch.

I had to add an override of isVectorLoadExtDesirable to stop DAG combine from combining sign_extend with loads after legalization since we legalize sextload using a load+sign_extend. Overriding this hook actually prevents a lot sextloads from being created in the first place.

I also had to add isel patterns because DAG combine blindly combines sign_extend+truncate to a smaller sign_extend which defeats what legalization was trying to do.

Differential Revision: https://reviews.llvm.org/D42407

llvm-svn: 323301

Some users may have a custom build system which gives a different
name to the libc++ archive (or does not create an archive at all,
instead passing the object files directly to the linker). Give those
users a way to disable auto-linking.

Differential Revision: https://reviews.llvm.org/D42436

llvm-svn: 323300

This is somewhat preferable since (in many cases) it allows llc
to be run directly on the .ll files without having to pass the
`-mtriple` argument.

Differential Revision: https://reviews.llvm.org/D42438

llvm-svn: 323299

Summary:
Currently, there are 2 ways to verify a DomTree:
* `DT.verify()` -- runs full tree verification and checks all the properties and gives a reason why the tree is incorrect. This is run by when EXPENSIVE_CHECKS are enabled or when `-verify-dom-info` flag is set.
* `DT.verifyDominatorTree()` -- constructs a fresh tree and compares it against the old one. This does not check any other tree properties (DFS number, levels), nor ensures that the construction algorithm is correct. Used by some passes inside assertions.

This patch introduces DomTree verification levels, that try to close the gape between the two ways of checking trees by introducing 3 verification levels:
- Full -- checks all properties, but can be slow (O(N^3)). Used when manually requested (e.g. `assert(DT.verify())`) or when  `-verify-dom-info` is set.
- Basic -- checks all properties except the sibling property, and compares the current tree with a freshly constructed one instead. This should catch almost all errors, but does not guarantee that the construction algorithm is correct. Used when EXPENSIVE checks are enabled.
- Fast -- checks only basic properties (reachablility, dfs numbers, levels, roots), and compares with a fresh tree. This is meant to replace the legacy `DT.verifyDominatorTree()` and in my tests doesn't cause any noticeable performance impact even in the most pessimistic examples.

When used to verify dom tree wrapper pass analysis on sqlite3, the 3 new levels make `opt -O3` take the following amount of time on my machine:
- no verification: 8.3s
- `DT.verify(VerificationLevel::Fast)`: 10.1s
- `DT.verify(VerificationLevel::Basic)`: 44.8s
- `DT.verify(VerificationLevel::Full)`: 1m 46.2s
(and the previous `DT.verifyDominatorTree()` is within the noise of the Fast level)

This patch makes `DT.verifyDominatorTree()` pick between the 3 verification levels depending on EXPENSIVE_CHECKS and `-verify-dom-info`.

Reviewers: dberlin, brzycki, davide, grosser, dmgreen

Reviewed By: dberlin, brzycki

Subscribers: MatzeB, llvm-commits

Differential Revision: https://reviews.llvm.org/D42337

llvm-svn: 323298

This is already a simplification, and should help with avoiding a plt
reference when calling an intrinsic with -fno-plt.

With this change we return false for null GVs, so the caller only
needs to check the new metadata to decide if it should use foo@plt or
*foo@got.

llvm-svn: 323297

llvm-svn: 323296

llvm-svn: 323295

llvm-svn: 323294

llvm-svn: 323293

Summary:
AVX512BW adds support for variable shift amount for 16-bit element
vectors.

Reviewers: craig.topper, RKSimon, spatel

Reviewed By: RKSimon

Subscribers: rengolin, tschuett, llvm-commits

Differential Revision: https://reviews.llvm.org/D42437

llvm-svn: 323292

https://reviews.llvm.org/D42402

A lot of these copies are useless (copies b/w VRegs having the same
regclass) and should be cleaned up.

llvm-svn: 323291

Also, fix crash when exporting an imported function.

Differential Revision: https://reviews.llvm.org/D42454

llvm-svn: 323290

Remove FeatureSlowMisaligned128Store from cyclone flags.
This flag causes splitting of 16 byte wide stores into 2 stored of 8
bytes. This was useful on older apple CPUs which were slow for 16byte
stores that were not aligned on 16byte. As the compiler often cannot
predict the actual alignment, the splitting was choosen.

This has been a topic for a lot of debate as the splitting also
decreases performance for some benchmarks. Measuring the effects on
newer apple chips (rdar://35525421) shows that it harms more cases than
it helps. So it is time to retire this workaround.

llvm-svn: 323289

Differential Revision: https://reviews.llvm.org/D42397

llvm-svn: 323288

llvm-svn: 323287

llvm-svn: 323286

- Test needs to be able to handle "clang.exe" on Windows
- Test needs to be able to handle either '/' or '\\' used as the path separator

Reviewed by Paul Robinson

llvm-svn: 323285

Theoretically, a PHI write can be added to any statement that represents
the incoming basic block. We previously always chose the last because
the incoming value's definition is guaranteed to be defined.

With this patch the PHI write is added to the statement that defines the
incoming value. It avoids the requirement for a scalar dependency between
the defining statement and the statement containing the write. As such the
logic for -polly-stmt-granularity=scalar-indep that ensures that there is
such scalar dependencies can be removed.

Differential Revision: https://reviews.llvm.org/D42147

llvm-svn: 323284

VirtualUse::create is only called for MemoryKind::Value, but its
consistency nonetheless checked in verifyUses(). PHI uses are always
inter-stmt dependencies, which was not considered by the constructor
method. The virtual and non-virtual execution paths were the same, such
that verifyUses did not encounter any inconsistencies.

llvm-svn: 323283

There seems to be an bug related to table relocations not being
written correctly in this case.  This change is intended simply
to increase the coverage, not fix the issue.

llvm-svn: 323282

This is to fix the bug reported in https://bugs.llvm.org/show_bug.cgi?id=34347#c6.
Currently, all  MaxAtomicInlineWidth of x86-32 targets are set to 64. However,
i386 doesn't support any cmpxchg related instructions. i486 only supports cmpxchg.
So in this patch MaxAtomicInlineWidth is reset as follows:
For i386, the MaxAtomicInlineWidth should be 0 because no cmpxchg is supported.
For i486, the MaxAtomicInlineWidth should be 32 because it supports cmpxchg.
For others 32 bits x86 cpu, the MaxAtomicInlineWidth should be 64 because of cmpxchg8b.

Differential Revision: https://reviews.llvm.org/D42154

llvm-svn: 323281

llvm-svn: 323280

llvm-svn: 323279

Summary:
Hooks in the allocation & deallocation paths can be a security risk (see for an
example https://scarybeastsecurity.blogspot.com/2016/11/0day-exploit-advancing-exploitation.html
which used the glibc's __free_hook to complete exploitation).

But some users have expressed a need for them, even if only for tests and
memory benchmarks. So allow for `__sanitizer_malloc_hook` &
`__sanitizer_free_hook` to be called if defined, and gate them behind a global
define `SCUDO_CAN_USE_HOOKS` defaulting to 0.

Reviewers: alekseyshl

Reviewed By: alekseyshl

Subscribers: #sanitizers, llvm-commits

Differential Revision: https://reviews.llvm.org/D42430

llvm-svn: 323278

llvm::Regex is still the slowest regex engine on earth, running it over
all instructions on X86 takes a while. Extract a prefix and use a binary
search to reduce the search space before we resort to regex matching.

There are a couple of caveats here:
- The generic opcodes are outside of the sorted enum. They're handled in an extra loop.
- If there's a top-level bar we can't use the prefix trick.
- We bail on top-level ?. This could be handled, but it's rare.

This brings the time to generate X86GenInstrInfo.inc from 21s to 4.7s on
my machine.

llvm-svn: 323277

llvm-svn: 323276

This matches the CodeGen tests and makes it a little easy
to run these from the command line manually.

Differential Revision: https://reviews.llvm.org/D42440

llvm-svn: 323275

llvm-svn: 323274