This is a follow-up for D70378 (Cover usage of LLD as a library).

While debugging an intermittent failure on a bot, I recalled this scenario which
causes the issue:

1.When executing lld/test/ELF/invalid/symtab-sh-info.s L45, we reach
  lld::elf::Obj-File::ObjFile() which goes straight into its base ELFFileBase(),
  then ELFFileBase::init().
2.At that point fatal() is thrown in lld/ELF/InputFiles.cpp L381, leaving a
  half-initialized ObjFile instance.
3.We then end up in lld::exitLld() and since we are running with LLD_IN_TEST, we
  hapily restore the control flow to CrashRecoveryContext::RunSafely() then back
  in lld::safeLldMain().
4.Before this patch, we called errorHandler().reset() just after, and this
  attempted to reset the associated SpecificAlloc<ObjFile<ELF64LE>>. That tried
  to free the half-initialized ObjFile instance, and more precisely its
  ObjFile::dwarf member.

Sometimes that worked, sometimes it failed and was catched by the
CrashRecoveryContext. This scenario was the reason we called
errorHandler().reset() through a CrashRecoveryContext.

But in some rare cases, the above repro somehow corrupted the heap, creating a
stack overflow. When the CrashRecoveryContext's filter (that is,
__except (ExceptionFilter(GetExceptionInformation()))) tried to handle the
exception, it crashed again since the stack was exhausted -- and that took the
whole application down. That is the issue seen on the bot. Locally it happens
about 1 times out of 15.

Now this situation can happen anywhere in LLD. Since catching stack overflows is
not a reliable scenario ATM when using CrashRecoveryContext, we're now
preventing further re-entrance when such failures occur, by signaling
lld::SafeReturn::canRunAgain=false. When running with LLD_IN_TEST=2 (or above),
only one iteration will be executed, instead of two.

Differential Revision: https://reviews.llvm.org/D88348

Add a test verifying that after the 'watchpoint' command, new values
of x86 debug registers can be read back correctly.  The primary purpose
of this test is to catch broken DRn reading and help debugging it.

Differential Revision: https://reviews.llvm.org/D91264

Fix Debug Register offsets to be specified relatively to UserArea
on FreeBSD/amd64 and FreeBSD/i386, and add them to UserArea on i386.
This fixes overlapping GPRs and DRs in gdb-remote protocol, making it
impossible to correctly get and set debug registers from the LLDB
client.

Differential Revision: https://reviews.llvm.org/D91254

This reverts commit 856fd98a. The type formatters
use inline namespaces to find the formatter that fits the type ABI, so they
can't just ignore the inline namespaces.

The failing tests should be fixed by da121fff .

Commit 5f12f4ff made suppressing inline namespaces
when printing typenames default to true. As we're using the inline namespaces
in LLDB to construct internal type names (which need internal namespaces in them
to, for example, differentiate libc++'s std::__1::string from the std::string
from libstdc++), this broke most of the type formatting logic.

For dllexported default constructors with default arguments, we export
default constructor closures which pass in the default args. (See D8331
for a good explanation.)

For templates, that means those default args must be instantiated even
if the function isn't called. That is done by the
InstantiateDefaultCtorDefaultArgs() function, but it wasn't done for
explicit specializations, causing asserts (see bug).

Differential revision: https://reviews.llvm.org/D91089

The tokens are already handled by the lexer. This revision exposes them
through the parser interface.

This revision also adds missing functions for question mark parsing and
completes the list of valid punctuation tokens in the documentation.

Differential Revision: https://reviews.llvm.org/D90907

[dllexport] Avoid assert for explicitly defaulted methods in explicit instantiation definitions (PR47683)

Clang was asserting due to attempting to codegen such methods twice.

Differential revision: https://reviews.llvm.org/D90849

Add an ODS-backed generator of default builders. This currently does not
support operation with attribute arguments, for which the builder is
just ignored. Attribute support will be introduced separately for
builders and accessors.

Default builders are always generated with the same number of result and
operand groups as the ODS specification, i.e. one group per each operand
or result. Optional elements accept None but cannot be omitted. Variadic
groups accept iterable objects and cannot be replaced with a single
object.

For some operations, it is possible to infer the result type given the
traits, but most traits rely on inline pieces of C++ that we cannot
(yet) forward to Python bindings. Since the Ops where the inference is
possible (having the `SameOperandAndResultTypes` trait or
`TypeMatchesWith` without transform field) are a small minority, they
also require the result type to make the builder syntax more consistent.

Reviewed By: stellaraccident

Differential Revision: https://reviews.llvm.org/D91190

Change the default type of v64 register class from v512i32 to v256f64.
Add a regression test also.

Reviewed By: simoll

Differential Revision: https://reviews.llvm.org/D91301

Added documentation about the bufferization features.
Furthermore, the usage of pre- and post-processing is described.
This also includes information about optimization functionalities.

Differential Revision: https://reviews.llvm.org/D90675

When passing SVE types as arguments to function calls we can run
out of hardware SVE registers. This is normally fine, since we
switch to an indirect mode where we pass a pointer to a SVE stack
object in a GPR. However, if we switch over part-way through
processing a SVE tuple then part of it will be in registers and
the other part will be on the stack.

I've fixed this by ensuring that:

1. When we don't have enough registers to allocate the whole block
   we mark any remaining SVE registers temporarily as allocated.
2. We temporarily remove the InConsecutiveRegs flags from the last
   tuple part argument and reinvoke the autogenerated calling
   convention handler. Doing this prevents the code from entering
   an infinite recursion and, in combination with 1), ensures we
   switch over to the Indirect mode.
3. After allocating a GPR register for the pointer to the tuple we
   then deallocate any SVE registers we marked as allocated in 1).
   We also set the InConsecutiveRegs flags back how they were before.
4. I've changed the AArch64ISelLowering LowerCALL and
   LowerFormalArguments functions to detect the start of a tuple,
   which involves allocating a single stack object and doing the
   correct numbers of legal loads and stores.

Differential Revision: https://reviews.llvm.org/D90219

This was implemented in 410b650e:
"Implement P0340R3: Make 'underlying_type' SFINAE-friendly. Reviewed as https://reviews.llvm.org/D63574

llvm-svn: 364094"

This change does two main things
1) An operation might have multiple dependences to the same
   producer. Not tracking them correctly can result in incorrect code
   generation with fusion. To rectify this the dependence tracking
   needs to also have the operand number in the consumer.
2) Improve the logic used to find the fused loops making it easier to
   follow. The only constraint for fusion is that linalg ops (on
   buffers) have update semantics for the result. Fusion should be
   such that only one iteration of the fused loop (which is also a
   tiled loop) must touch only one (disjoint) tile of the output. This
   could be relaxed by allowing for recomputation that is the default
   when oeprands are tensors, or can be made legal with promotion of
   the fused view (in future).

Differential Revision: https://reviews.llvm.org/D90579

A piece of logic of `isLoopInvariantExitCondDuringFirstIterations` is actually
a generalized predicate monotonicity check. This patch moves it into the
corresponding method and generalizes it a bit.

Differential Revision: https://reviews.llvm.org/D90395
Reviewed By: apilipenko

Test plan: check-llvm, check-clang

Reviewers: lxfind, junparser

Differential Revision: https://reviews.llvm.org/D91243

This reverts commit 8bc7b927, which landed by accident.

Exposing the C versions of the methods of the sparse runtime support lib
through header files will enable using the same methods in an MLIR program
as well as a C++ program, which will simplify future benchmarking comparisons
(e.g. comparing MLIR generated code with eigen for Matrix Market sparse matrices).

Reviewed By: penpornk

Differential Revision: https://reviews.llvm.org/D91316

Sometimes the an instruction we are trying to widen is used by the IV
(which means the instruction is the IV increment). Currently this may
prevent its widening. We should ignore such user because it will be
dead once the transform is done anyways.

Differential Revision: https://reviews.llvm.org/D90920
Reviewed By: fhahn

In the existing logic, for a given alloca, as long as its pointer value is stored into another location, it's considered as escaped.
This is a bit too conservative. Specifically, in non-optimized build mode, it's often to have patterns of code that first store an alloca somewhere and then load it right away.
These used should be handled without conservatively marking them escaped.

This patch tracks how the memory location where an alloca pointer is stored into is being used. As long as we only try to load from that location and nothing else, we can still
consider the original alloca not escaping and keep it on the stack instead of putting it on the frame.

Differential Revision: https://reviews.llvm.org/D91305

InstCombine canonicalizes 'sub nuw' instructions to 'add' without the
`nuw` flag. The typical case where we see it is decrementing induction
variables. For them, IndVars fails to prove that it's legal to widen them,
and inserts unprofitable `zext`'s.

This patch adds recognition of such pattern using SCEV.

Differential Revision: https://reviews.llvm.org/D89550
Reviewed By: fhahn, skatkov

right union member.

Should fix the armv8 buildbot.

We have option -mabi=ieeelongdouble to set current long double to
IEEEquad semantics. Like what GCC does, we need to define
__LONG_DOUBLE_IEEE128__ macro in this case, and __LONG_DOUBLE_IBM128__
if using PPCDoubleDouble.

Reviewed By: steven.zhang

Differential Revision: https://reviews.llvm.org/D90208

improvements to Clang's type printing.

This CL integrates the new sparse annotations (hereto merely added as fully
transparent attributes) more tightly to the generic linalg op in order to add
verification of the annotations' consistency as well as to make make other
passes more aware of their presence (in the long run, rewriting rules must
preserve the integrity of the annotations).

Reviewed By: nicolasvasilache

Differential Revision: https://reviews.llvm.org/D91224

Summary:
This patch begins to add support for a set of scripts that can be used to get information from OpenMP programs to better describe problems and eventually show the data to the user in formatted output. Right now the only support is forformatting the register and memory usage reports from ptxas and nvlink. This is simply done as a wrapper around clang and clang++.

Reviewers: jdoerfert

DIfferential Revision: https://reviews.llvm.org/D91085

With 6213ed06 the master callback was renamed to masked.
The multiplex tests must check for masked now.

The implementation of Messages with forward_list<> makes some
nonstandard assumptions about the validity of iterators that don't
hold up with MSVC's implementation.  Use list<> instead.  The
measured performance is comparable.

This change obviated a distinction between two member functions
of Messages, and the uses of one have been replaced with calls
to the other.

Similar usage in CharBuffer was also replaced for consistency.

Differential revision: https://reviews.llvm.org/D91210

Non-mechanical changes:
 - Added FIXME to StringLiteral to cover multi-token string literals.
 - LiteralExpression::getLiteralToken() is gone. (It was never called)
   This is because we don't codegen methods in Alternatives
   It's conceptually suspect if we consider multi-token string literals, though.

Differential Revision: https://reviews.llvm.org/D91277

Following discussion in D91193, a change made in D88792 was not quite right.
This restores the message argument, and switches from `expect` to `runCmd`.

Differential Revision: https://reviews.llvm.org/D91206

Bold and fixed-width do not appear to mix well.

Fixes some formatting and wording, and adds a roadmap section.

We need to be able to call function pointers. Inline the dispatch
function.

Also inline the context projection function.

Transfer debug locations from the suspend point to the inlined functions.

Use the function argument index instead of the function argument in
coro.id.async. This solves any spurious use issues.

Coerce the arguments of the tail call function at a suspend point. The LLVM
optimizer seems to drop casts leading to a vararg intrinsic.

rdar://70097093

Differential Revision: https://reviews.llvm.org/D91098

Some targets may add required passes via
TargetMachine::registerPassBuilderCallbacks(). We need to run those even
under -O0. As an example, BPFTargetMachine adds
BPFAbstractMemberAccessPass, a required pass.

This also allows us to clean up BackendUtil.cpp (and out-of-tree Rust
usage of the NPM) by allowing us to share added passes like coroutines
and sanitizers between -O0 and other optimization levels.

Since callbacks may end up not adding passes, we need to check if the
pass managers are empty before adding them, so PassManager now has an
isEmpty() function. For example, polly adds callbacks but doesn't always
add passes in those callbacks, so this is necessary to keep
-debug-pass-manager tests' output from changing depending on if polly is
enabled or not.

Tests are a continuation of those added in
https://reviews.llvm.org/D89083.

Reviewed By: asbirlea, Meinersbur

Differential Revision: https://reviews.llvm.org/D89158

except where they are necessary to disambiguate the target.

This substantially improves diagnostics from the standard library,
which are otherwise full of `::__1::` noise.