When shadow stack from Intel CET is enabled, the first instruction of all
indirect branch targets must be a special instruction, ENDBR.

lib/asan/asan_interceptors.cc has

...
  int res = REAL(swapcontext)(oucp, ucp);
...

REAL(swapcontext) is a function pointer to swapcontext in libc.  Since
swapcontext may return via indirect branch on x86 when shadow stack is
enabled, as in this case,

int res = REAL(swapcontext)(oucp, ucp);
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^  This function may be
returned via an indirect branch.

Here compiler must insert ENDBR after call, like

call *bar(%rip)
endbr64

I opened an LLVM bug:

https://bugs.llvm.org/show_bug.cgi?id=38207

to add the indirect_return attribute so that it can be used to inform
compiler to insert ENDBR after REAL(swapcontext) call.  We mark
REAL(swapcontext) with the indirect_return attribute if it is available.

This fixed:

https://bugs.llvm.org/show_bug.cgi?id=38249

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D49608

llvm-svn: 337603

Submitted on behalf of Annie Cherkaev (@anniecherk)

Added a flag which, when enabled, documents only those methods and
fields which have a Public attribute.

Differential Revision: https://reviews.llvm.org/D48395

llvm-svn: 337602

This only shows up with asan when the stars align in a bad way.

llvm-svn: 337601

llvm-svn: 337600

llvm-svn: 337599

If a binary is stripped, which can remove discardable sections (except
for the .reloc section, which also is marked as discardable as it isn't
loaded at runtime, only read by the loader), the .reloc section should
be first of them, in order not to create gaps in the image.

Previously, binaries with relocations were broken if they were stripped
by GNU binutils strip. Trying to execute such binaries produces an error
about "xx is not a valid win32 application".

This fixes GNU binutils bug 23348.

Prior to SVN r329370 (which didn't intend to have functional changes),
the code for moving discardable sections to the end didn't clearly
express how other discardable sections should be ordered compared to
.reloc, but the change retained the exact same end result as before.

After SVN r329370, the code (and comments) more clearly indicate that
it tries to make the .reloc section the absolutely last one; this patch
changes that.

This matches how GNU binutils ld sorts .reloc compared to dwarf debug
info sections.

Differential Revision: https://reviews.llvm.org/D49351



Signed-off-by: Martin Storsjö <martin@martin.st>
llvm-svn: 337598

llvm-svn: 337597

Incidentally all allocations that we currently perform were
properly aligned, but this was only an accident.

Thanks to Erik Pilkington for catching this.

llvm-svn: 337596

deprecating SymbolResolver and AsynchronousSymbolQuery.

Both lookup overloads take a VSO search order to perform the lookup. The first
overload is non-blocking and takes OnResolved and OnReady callbacks. The second
is blocking, takes a boolean flag to indicate whether to wait until all symbols
are ready, and returns a SymbolMap. Both overloads take a RegisterDependencies
function to register symbol dependencies (if any) on the query.

llvm-svn: 337595

This discards the unresolved symbols set and returns the flags map directly
(rather than mutating it via the first argument).

The unresolved symbols result made it easy to chain lookupFlags calls, but such
chaining should be rare to non-existant (especially now that symbol resolvers
are being deprecated) so the simpler method signature is preferable.

llvm-svn: 337594

A search order is a list of VSOs to be searched linearly to find symbols. Each
VSO now has a search order that will be used when fixing up definitions in that
VSO. Each VSO's search order defaults to just that VSO itself.

This is a first step towards removing symbol resolvers from ORC altogether. In
practice symbol resolvers tended to be used to implement a search order anyway,
sometimes with additional programatic generation of symbols. Now that VSOs
support programmatic generation of definitions via fallback generators, search
orders provide a cleaner way to achieve the desired effect (while removing a lot
of boilerplate).

llvm-svn: 337593

-Winconsistent-missing-override complains about this.

llvm-svn: 337592

Also remove a broken test case.

llvm-svn: 337591

Ideally our ISD node types going into the isel table would have types consistent with their instruction domain. This prevents us having to duplicate patterns with different types for the same instruction.

Unfortunately, it seems our shuffle combining is currently relying on this a little remove some bitcasts. This seems to enable some switching between shufps and shufd. Hopefully there's some way we can address this in the combining.

Differential Revision: https://reviews.llvm.org/D49280

llvm-svn: 337590

CombineTo is most useful when you need to replace multiple results, avoid the worklist management, or you need to something else after the combine, etc. Otherwise you should be able to just return the new node and let DAGCombiner go through its usual worklist code.

All of the places changed in this patch look to be standard cases where we should be able to use the more stand behavior of just returning the new node.

Differential Revision: https://reviews.llvm.org/D49569

llvm-svn: 337589

This is due to a difference in MS ABI which is why I didn't see
it locally.  The included fix should work on all compilers.

llvm-svn: 337588

CUDA-9.2 made all integer SIMD functions into compiler builtins,
so clang no longer has access to the implementation of these
functions in either headers of libdevice and has to provide
its own implementation.

This is mostly a 1:1 mapping to a corresponding PTX instructions
with an exception of vhadd2/vhadd4 that don't have an equivalent
instruction and had to be implemented with a bit hack.

Performance of this implementation will be suboptimal for SM_50
and newer GPUs where PTXAS generates noticeably worse code for
the SIMD instructions compared to the code it generates
for the inline assembly generated by nvcc (or used to come
with CUDA headers).

Differential Revision: https://reviews.llvm.org/D49274

llvm-svn: 337587

llvm-svn: 337586

Discovered because of: https://bugs.llvm.org/show_bug.cgi?id=38235

It seems to me that a scoped enum should NOT be an integral constant expression
without a cast, so this seems like a sensical change.

Attributes that check for an integer parameter simply use this function to
ensure that they have an integer, so it was previously allowing a scoped enum.

Also added a test based on Richard's feedback to ensure that case labels still work.

Differential Revision: https://reviews.llvm.org/D49599

llvm-svn: 337585

This adds initial support for a demangling library (LLVMDemangle)
and tool (llvm-undname) for demangling Microsoft names.  This
doesn't cover 100% of cases and there are some known limitations
which I intend to address in followup patches, at least until such
time that we have (near) 100% test coverage matching up with all
of the test cases in clang/test/CodeGenCXX/mangle-ms-*.

Differential Revision: https://reviews.llvm.org/D49552

llvm-svn: 337584

llvm-svn: 337583

ItaniumDemangle had a small NFC refactor to make some of its
code reusable by the newly added Microsoft demangler.  To keep
the libcxxabi demangler as close as possible to the master copy
this refactor is being merged over.

Differential Revision: https://reviews.llvm.org/D49575

llvm-svn: 337582

Summary:
When splitting predecessors in BasicBlockUtils, we create a new block as an immediate predecessor of the original BB, then we connect a given set of predecessors to the new block.
The API in this patch will be used to update MemoryPhis for this CFG change.
If all predecessors are being moved, we move the MemoryPhi directly. Otherwise we create a new MemoryPhi in the NewBB and populate its incoming values, while deleting them from BB's Phi.
[Split from D45299 for easier review]

Reviewers: george.burgess.iv

Subscribers: sanjoy, jlebar, Prazek, llvm-commits

Differential Revision: https://reviews.llvm.org/D49156

llvm-svn: 337581

no-ops.

A non-escaping block on the stack will never be called after its
lifetime ends, so it doesn't have to be copied to the heap. To prevent
a non-escaping block from being copied to the heap, this patch sets
field 'isa' of the block object to NSConcreteGlobalBlock and sets the
BLOCK_IS_GLOBAL bit of field 'flags', which causes the runtime to treat
the block as if it were a global block (calling _Block_copy on the block
just returns the original block and calling _Block_release is a no-op).

Also, a new flag bit 'BLOCK_IS_NOESCAPE' is added, which allows the
runtime or tools to distinguish between true global blocks and
non-escaping blocks.

rdar://problem/39352313

Differential Revision: https://reviews.llvm.org/D49303

llvm-svn: 337580

`VM_MEMORY_SANITIZER`.

It turns out that `VM_MEMORY_ANALYSIS_TOOL` is already reserved for
use by other tools so switch to a tag reserved for use by the Sanitizers.

rdar://problem/41969783

Differential Revision: https://reviews.llvm.org/D49603

llvm-svn: 337579

We can safely use getConstant here as we're still lowering, which allows constant folding to kick in and simplify the vector shift codegen.

Noticed while working on D49562.

llvm-svn: 337578

Make sure NewSI is used in materializeStores()

llvm-svn: 337577

bool_constant is C++17.

llvm-svn: 337576

Enable the optimization of operations on DPR and SPR via a feature instead
of checking the target.

Differential revision: https://reviews.llvm.org/D49463

llvm-svn: 337575

This is analogous to std::any which is only available in C++17.

Differential Revision: https://reviews.llvm.org/D48807

llvm-svn: 337573

This is a new modernized VS integration installer.  It adds a
Visual Studio .sln file which, when built, outputs a VSIX that can
be used to install ourselves as a "real" Visual Studio Extension.
We can even upload this extension to the visual studio marketplace.

This fixes a longstanding problem where we didn't support installing
into VS 2017 and higher.  In addition to supporting VS 2017, due
to the way this is written we now longer need to do anything special
to support future versions of VS as well.  Everything should
"just work".  This also fixes several bugs with our old integration,
such as MSBuild triggering full rebuilds when /Zi was used.

Finally, we add a new UI page called "LLVM" which becomes visible
when the LLVM toolchain is selected.  For now this only contains
one option which is the path to clang-cl.exe, but in the future
we can add more things here.

Differential Revision: https://reviews.llvm.org/D42762

llvm-svn: 337572

When pointer checking is enabled, it's important that every pointer is
checked before its value is used.
For stores MSan used to generate code that calculates shadow/origin
addresses from a pointer before checking it.
For userspace this isn't a problem, because the shadow calculation code
is quite simple and compiler is able to move it after the check on -O2.
But for KMSAN getShadowOriginPtr() creates a runtime call, so we want the
check to be performed strictly before that call.

Swapping materializeChecks() and materializeStores() resolves the issue:
both functions insert code before the given IR location, so the new
insertion order guarantees that the code calculating shadow address is
between the address check and the memory access.

llvm-svn: 337571

Improve AVX1 256-bit vector HADD/HSUB matching by using SplitOpsAndApply to split into 128-bit instructions.

llvm-svn: 337568

Summary: In Python 3, sys.stdout.write expects a string rather than bytes. In order to be able to write the bytes to stdout, we need to use the buffer directly instead. This change is borrowing the implementation for writing to stdout that cat.py uses. Note that we cannot use cat.py directly because the file we are trying to open is a gzip file.

Reviewers: asmith, bkramer, alexshap, jakehehrlich

Reviewed By: alexshap, jakehehrlich

Subscribers: jakehehrlich, llvm-commits

Differential Revision: https://reviews.llvm.org/D49515

llvm-svn: 337567

llvm-svn: 337566

llvm-svn: 337565

I changed a variable's type from pointer to reference, but forgot to
update the assert-only code.

llvm-svn: 337564

Check for construction-time folding for incomplete AND nodes in
BackwardsPropagateMask.

Fixes PR38185.

Reviewers: RKSimon, samparker

Reviewed By: samparker

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D49444

llvm-svn: 337563

Summary:
Each of the four methods had a dozen lines and was doing almost exactly
the same thing: get the appropriate accelerator table kind and insert an
entry into it. I move this common logic to a helper function and make
these methods delegate to it.

This came up in the context of D49493, where I've needed to make adding
a string to a string pool slightly more complicated, and it seemed to
make sense to do it in one place instead of five.

To make this work I've needed to unify the interface of the AccelTable
data types, as some used to store DIE& and others DIE*. I chose to unify
to a reference as that's what the caller uses.

This technically isn't NFC, because it changes the StringPool used for
apple tables in the DWO case (now it uses the main file like DWARF v5
instead of the DWO file). However, that shouldn't matter, as DWO is not
a thing on apple targets (clang frontend simply ignores -gsplit-dwarf).

Reviewers: JDevlieghere, aprantl, probinson

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D49542

llvm-svn: 337562

llvm-svn: 337561