[X86] Add an override of targetShrinkDemandedConstant to limit the damage that shrinkdemandedbits can do to zext_in_reg operations

Summary:
This patch adds an implementation of targetShrinkDemandedConstant that tries to keep shrinkdemandedbits from removing bits that would otherwise have been recognized as a movzx.

We still need a follow patch to stop moving ands across srl if the and could be represented as a movzx before the shift but not after. I think this should help with some of the cases that D42088 ended up removing during isel.

Reviewers: spatel, RKSimon

Reviewed By: spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D42265

llvm-svn: 323048

Summary: This patch adds -mrdpid/-mno-rdpid and the rdpid intrinsic. The corresponding LLVM commit has already been made.

Reviewers: RKSimon, spatel, zvi, AndreiGrischenko

Reviewed By: RKSimon

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D42272

llvm-svn: 323047

[X86] Put the code that defines __GCC_HAVE_SYNC_COMPARE_AND_SWAP_16 for the preprocessor with the other __GCC_HAVE_SYNC_COMPARE_AND_SWAP_* defines. NFC

llvm-svn: 323046

llvm-svn: 323045

A few build bots failed with r323042 because they are not configured to
build the SystemZ target.

llvm-svn: 323044

This fold is proposed in D42032.

llvm-svn: 323043

This was completely broken, but hopefully fixed by this patch.

In cases where it is needed, a vector with non byte-sized elements is stored
by extracting, zero-extending, shift:ing and or:ing the elements into an
integer of the same width as the vector, which is then stored.

Review: Eli Friedman, Ulrich Weigand
https://reviews.llvm.org/D42100#inline-369520
https://bugs.llvm.org/show_bug.cgi?id=35520

llvm-svn: 323042

except Darwin and Windows.  This prevents inserting an environment
variable with an empty name (which is illegal and leads to a Python
exception) on any of the BSDs.

llvm-svn: 323041

except Darwin and Windows.  This prevents inserting an environment
variable with an empty name (which is illegal and leads to a Python
exception) on any of the BSDs.

llvm-svn: 323040

Summary:
Make __clear_cache() invoke the platform's cache flush function
on OpenBSD/mips64.

Reviewers: krytarowski

Reviewed By: krytarowski

Subscribers: sdardis, dberris, arichardson, krytarowski, llvm-commits, #sanitizers

Differential Revision: https://reviews.llvm.org/D42332

llvm-svn: 323039

This fixes PR35733.

Differential Revision: https://reviews.llvm.org/D41632

llvm-svn: 323036

This (together with the corresponding LLD commit, that contains the
testcase updates) fixes PR35733.

Differential Revision: https://reviews.llvm.org/D41631

llvm-svn: 323035

These fix some odd cfg cases where batch-updating the post
dom tree fails. Usually around infinite loops and roots
ending up being different.

Differential Revision: https://reviews.llvm.org/D42247

llvm-svn: 323034

This reverts commit r323032: failing on the sanitizer-x86_64-linux-autoconf bot.

llvm-svn: 323033

add_custom_libcxx uses the just built compiler and installs the
built libc++, e.g. for testing, neither of which is desirable in
case of Fuzzer where the libc++ should be built using the host
compiler and it's only linked into the libFuzzer and should never
be installed. This change introduces additional arguments to
add_custom_libcxx to allow parametrizing its behavior.

Differential Revision: https://reviews.llvm.org/D42330

llvm-svn: 323032

[X86] Add some more v32i1 shuffle tests with shuffles between mask creation and mask usage rather than being just shuffling input arguments.

The existing tests just tested shuffles of v32i1 inputs, but arguments are promoted to v32i8. So it wasn't a good demonstration of v32i1 shuffle handling.

The new test cases use compares and selects to get k-register operations around the shuffle.

This is prep work for demonstrating changes from D42031.

llvm-svn: 323031

D42265 and D42313 should help with some of these.

llvm-svn: 323030

This triggers compiler error when building sanitizers for Fuchsia.

Differential Revision: https://reviews.llvm.org/D42328

llvm-svn: 323029

This reverts commit r323027: it breaks the SanitizerLintCheck.

llvm-svn: 323028

This triggers compiler error when building sanitizers for Fuchsia.

Differential Revision: https://reviews.llvm.org/D42328

llvm-svn: 323027

sequentially.

The current implementation of commands in
`test/sanitizer_common/ios_commands/` for iOS devices cannot be executed
in parallel which results in the ASan and TSan tests failing when
executed in parallel by lit which was the default behaviour.

We now force the ASan and TSan tests to be a new parallelism group named
`darwin-ios-device-sanitizer` which allows only one test to be run at a
time.  We also emit a warning informing the user that tests are being
run sequentially.

This only applies if the target is an iOS device.

Differential Revision: https://reviews.llvm.org/D42156

llvm-svn: 323026

Its much easier to export it via setHidden(false), now that
that is a thing.

As a side effect the start function is not longer always exports first
(becuase its being exported just like all the other function).

Differential Revision: https://reviews.llvm.org/D42321

llvm-svn: 323025

Differential Revision: https://reviews.llvm.org/D42327

llvm-svn: 323024

Remove the missed check update for the removal of the x86 specific
vector call on ARM.

llvm-svn: 323023

Summary:
kvm - kernel memory interface

The kvm(3) functions like kvm_open(), kvm_getargv() or kvm_getenvv()
are used in programs that can request information about a kernel and
its processes. The LLVM sanitizers will make use of them on NetBSD.

Sponsored by <The NetBSD Foundation>

Reviewers: joerg, vitalybuka, dvyukov

Reviewed By: vitalybuka

Subscribers: llvm-commits, cfe-commits, #sanitizers

Tags: #sanitizers

Differential Revision: https://reviews.llvm.org/D42017

llvm-svn: 323022

The ARM backend is not guaranteed to be present on x86, move the test to
the ARM tests.

llvm-svn: 323021

This code was needed back when we were not able to write
out the synthetic symbol for main.

Add tests to make sure we can handle this now.

Differential Revision: https://reviews.llvm.org/D42322

llvm-svn: 323020

Summary:
The localtime symbol is mangled to __locatime50
on NetBSD.

Sponsored by <The NetBSD Foundation>

Reviewers: joerg, vitalybuka

Reviewed By: vitalybuka

Subscribers: kubamracek, llvm-commits, #sanitizers

Tags: #sanitizers

Differential Revision: https://reviews.llvm.org/D42045

llvm-svn: 323019

Summary:
The accept4() function first appeared in NetBSD 8.0.

Sponsored by <The NetBSD Foundation>

Reviewers: joerg, vitalybuka

Reviewed By: vitalybuka

Subscribers: llvm-commits, srhines, kubamracek, #sanitizers

Tags: #sanitizers

Differential Revision: https://reviews.llvm.org/D42046

llvm-svn: 323018

`llvm.used` contains a list of pointers to named values which the
compiler, assembler, and linker are required to treat as if there is a
reference that they cannot see.  Ensure that the symbols are preserved
by adding an explicit `-include` reference to the linker command.

llvm-svn: 323017

[X86] Teach X86 codegen to use vector width preference to avoid promoting to 512-bit types when VLX is enabled and the preference is for a smaller size.

This change applies to places where we would turn 128/256-bit code into 512-bit in order to get a wider element type through sext/zext. Any 512-bit types that already existed in the IR/DAG will be left that way.

The width preference has no effect on codegen behavior when the target does not have AVX512 enabled. So AVX/AVX2 codegen cannot be limited via this mechanism yet.

If the preference is lower than 256 we may still use a 256 bit type to do the operation. Constraining to 128 bits makes it much more difficult to support some operations. For many of these cases we need to change element width while keeping element count constant which is easiest done by switching between 256 and 128 bit.

The preference is only obeyed when AVX512 and VLX are available. This means the preference is not obeyed for KNL, but is obeyed for SKX, Cannonlake, and Icelake. For KNL, the only way to do masked operation is on 512-bit registers so we would have to completely disable masking to obey the preference. We would also lose support for gather, scatter, ctlz, vXi64 multiplies, etc. This may change in the future, but this simplifies the initial implementation.

Differential Revision: https://reviews.llvm.org/D41895

llvm-svn: 323016

[X86] Add support for passing 'prefer-vector-width' function attribute into X86Subtarget and exposing via X86's getRegisterWidth TTI interface.

This will cause the vectorizers to do some limiting of the vector widths they create. This is not a strict limit. There are reasons I know of that the loop vectorizer will generate larger vectors for.

I've written this in such a way that the interface will only return a properly supported width(0/128/256/512) even if the attribute says something funny like 384 or 10.

This has been split from D41895 with the remainder in a follow up commit.

llvm-svn: 323015

Compiler doesn't know the fact that Config->WordSize * 8 is always a
power of two, so it had to use the div instruction to divide some
number with C.

llvm-svn: 323014

MemToShadowImpl() maps lower addresses to a memory space out of sanitizers
range. The simplest example is address 0 which is mapped to 0x2000000000

static const uptr kShadowBeg     = 0x2400000000ull;

but accessing the address during tsan execution will lead to a segmentation
fault.

This patch expands the range used by the sanitizer and ensures that 1/8 of
the maximum valid address in the virtual address spaces is used for shadow
memory.

Patch by Milos Stojanovic.

Differential Revision: https://reviews.llvm.org/D41777

llvm-svn: 323013

nullptr_t can't be used left of boolean &&

llvm-svn: 323012

Adds a check to the Fuchsia module to warn when a class
inherits from multiple classes that are not pure virtual.

See https://fuchsia.googlesource.com/zircon/+/master/docs/cxx.md
for reference.

Differential Revision: https://reviews.llvm.org/D40580

llvm-svn: 323011

I created https://reviews.llvm.org/D42202 to see how large the bloom
filter should be. With that patch, I tested various bloom filter sizes
with the following commands:

  $ cmake -GNinja -DCMAKE_BUILD_TYPE=Debug -DLLVM_ENABLE_LLD=true \
    -DLLVM_ENABLE_PROJECTS='clang;lld' -DBUILD_SHARED_LIBS=ON \
    -DCMAKE_SHARED_LINKER_FLAGS=-Wl,-bloom-filter-bits=<some integer> \
    ../llvm-project/llvm
  $ rm -f $(find . -name \*.so.7.0.0svn)
  $ ninja lld
  $ LD_BIND_NOW=1 perf stat bin/ld.lld

Here is the result:

  -bloom-filter-bits=8   0.220351609 seconds
  -bloom-filter-bits=10  0.217146597 seconds
  -bloom-filter-bits=12  0.206870826 seconds
  -bloom-filter-bits=16  0.209456312 seconds
  -bloom-filter-bits=32  0.195092075 seconds

Currently we allocate 8 bits for a symbol, but according to the above
result, that number is not optimal. Even though the numbers follow the
diminishing return rule, the point where a marginal improvement becomes
too small is not -bloom-filter-bits=8 but 12. So this patch sets it to 12.

Differential Revision: https://reviews.llvm.org/D42204

llvm-svn: 323010

to @objc_autorelease if its operand is a PHI and the PHI has an
equivalent value that is used by a return instruction.

For example, ARC optimizer shouldn't replace the call in the following
example, as doing so breaks the AutoreleaseRV/RetainRV optimization:

  %v1 = bitcast i32* %v0 to i8*
  br label %bb3
bb2:
  %v3 = bitcast i32* %v2 to i8*
  br label %bb3
bb3:
  %p = phi i8* [ %v1, %bb1 ], [ %v3, %bb2 ]
  %retval = phi i32* [ %v0, %bb1 ], [ %v2, %bb2 ] ; equivalent to %p
  %v4 = tail call i8* @objc_autoreleaseReturnValue(i8* %p)
  ret i32* %retval

Also, make sure ObjCARCContract replaces @objc_autoreleaseReturnValue's
operand uses with its value so that the call gets tail-called.

rdar://problem/15894705

llvm-svn: 323009

This fixes PR32732 by updating CurLexerKind to reflect available lexers.
We were hitting null pointer in Preprocessor::Lex because CurLexerKind
was CLK_Lexer but CurLexer was null. And we set it to null in
Preprocessor::HandleEndOfFile when exiting a file with code completion
point.

To reproduce the crash it is important for a comment to be inside a
class specifier. In this case in Parser::ParseClassSpecifier we improve
error recovery by pushing a semicolon token back into the preprocessor
and later on try to lex a token because we haven't reached the end of
file.

Also clang crashes only on code completion in included file, i.e. when
IncludeMacroStack is not empty. Though we reset CurLexer even if include
stack is empty. The difference is that during pushing back a semicolon
token, preprocessor calls EnterCachingLexMode which decides it is
already in caching mode because various lexers are null and
IncludeMacroStack is not empty. As the result, CurLexerKind remains
CLK_Lexer instead of updating to CLK_CachingLexer.

rdar://problem/34787685

Reviewers: akyrtzi, doug.gregor, arphaman

Reviewed By: arphaman

Subscribers: cfe-commits, kfunk, arphaman, nemanjai, kbarton

Differential Revision: https://reviews.llvm.org/D41688

llvm-svn: 323008

in TestBase::getBuildArtifact(). This NFC commit is in preparation for
https://reviews.llvm.org/D42281 (compile the LLDB tests out-of-tree).

Differential Revision: https://reviews.llvm.org/D42280

llvm-svn: 323007