Operator new must align allocations for types with large alignment.

Before c++17 behavior was implementation defined and both clang and gc++
before 11 ignored alignment. Miss-aligned objects mysteriously crashed
tests on Ubuntu 14.

Alternatives are compile with -std=c++17 or -faligned-new, but they were
discarded as less portable.

Reviewed By: hctim

Differential Revision: https://reviews.llvm.org/D101874

This simply applies Howard's commit 4c80bfbd consistently
across all the associative and unordered container tests.

"unord.set/insert_hint_const_lvalue.pass.cpp" failed with `-D_LIBCPP_DEBUG=1`
before this patch; it was the only one that incorrectly reused
invalid iterator `e`. The others already used valid iterators
(generally `c.end()`); I'm just making them all match the same pattern
of usage: "e, then r, then c.end() for the rest."

Differential Revision: https://reviews.llvm.org/D101679

Convert to a primitive type first; then use primitive `>=` on that value.

Differential Revision: https://reviews.llvm.org/D101678

`__debug_less` ends up running the comparator up-to-twice per comparison,
because whenever `(x < y)` it goes on to verify that `!(y < x)`.
This breaks the strict "Complexity" guarantees of algorithms like
`inplace_merge`, which we test in the test suite. So, just skip the
complexity assertions in debug mode.

Differential Revision: https://reviews.llvm.org/D101677

The range of char pointers [data, data+size] is a valid closed range,
but the range [begin, end) is valid only half-open.

Differential Revision: https://reviews.llvm.org/D101676

This appears to be a bug in our string::assign: when assigning into
a longer string, from a shorter snippet of itself, we invalidate
iterators before doing the copy. We should invalidate them afterward.
Also drive-by improve the formatting of a function header.

Differential Revision: https://reviews.llvm.org/D101675

This allocator is not intended for libc++'s users to use;
it's strictly an implementation detail of `src/locale.cpp`.
So, move it to the `src/include/` directory.

Drive-by const-qualify its comparison operators.

For consistency with `__hidden_allocator` (defined in `src/thread.cpp`),
do *not* remove it from "libcxx/lib/libc++unexp.exp",
"libcxx/utils/symcheck-blacklists/linux_blacklist.txt", etc.

Differential Revision: https://reviews.llvm.org/D101293

Update the SIMD builtin load functions to take pointers to const data and update
the intrinsics themselves to not cast away constness.

Differential Revision: https://reviews.llvm.org/D101884

Make the inputs to all narrowing builtins signed, which is how they are
interpreted by the underlying instructions (only the result changes sign
between instructions).

Differential Revision: https://reviews.llvm.org/D101883

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D101823

Looks like the PointerUnion casting cares about const-ness...

On Windows, static vs DLL linking affects details in quite a few
cases, so it's good to have coverage for both cases.

Testing with static linking also increases coverage for a number of
cases and individual checks that have had to be waived for the DLL
case, and allows testing libc++experimental, increasing the number
of test cases actually executed by 180 (176 new tests from
libc++experimental and 4 ones that are XFAIL windows-dll).

Also drop the "generic-" prefix from these configuration names, as
they're perhaps not what the "generic" prefix intended originally
in the other generic-posix configurations.

Differential Revision: https://reviews.llvm.org/D101565

The WebAssembly SIMD intrinsics in wasm_simd128.h generally try not to require
any particular alignment for memory operations to be maximally flexible. For
builtin memory access functions and their corresponding LLVM IR intrinsics,
there's no way to set the expected alignment, so the best we can do is set the
alignment to 1 in the backend. This change means that the alignment hints in the
emitted code will no longer be incorrect when users use the intrinsics to access
unaligned data.

Differential Revision: https://reviews.llvm.org/D101850

[libomptarget] Initial documentation on amdgpu offload

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D101927

The problem was introduced in D100348.

It's really hard to trigger the bug in a stress test - the race is just too
narrow - but the new checks in Thread::Init should at least provide usable
diagnostic if the problem ever returns.

Differential Revision: https://reviews.llvm.org/D101881

ARM_RELOC_BR24 is used for BL/BLX instructions from within ARM (i.e. not
Thumb) code. This diff just handles the basic case: branches from ARM to
ARM, or from ARM to Thumb where no shimming is required. (See comments
in ARM.cpp for why shims are required.)

Note: I will likely be deprioritizing ARM work for the near future to
focus on other parts of LLD. Apologies for the half-done state of this;
I'm just trying to wrap up what I've already worked on.

Reviewed By: #lld-macho, alexshap

Differential Revision: https://reviews.llvm.org/D101814

We need to account for path rerooting when generating the response
file. We could either reroot the paths before generating the file, or pass
through the original filenames and change just the syslibroot. I've opted for
the latter, in order that the reproduction run more closely mirrors the
original.

We must also be careful *not* to make an absolute path relative if it is
shadowed by a rerooted path. See repro6.tar in reroot-path.s for
details.

I've moved the call to `createResponseFile()` after the initialization of
`config->systemLibraryRoots`, since it now needs to know what those roots are.

Reviewed By: #lld-macho, oontvoo

Differential Revision: https://reviews.llvm.org/D101224

The current code accounts for two possible layouts, but there is at
least a third supported layout: clang-tools-extra may also be checked
out as clang/tools/extra with the releases, which was not yet handled.
Rather than treating that as a special case, use the location of
CompletionModel.cmake to handle all three cases. This should address the
problems that prompted D96787 and the problems that prompted the
proposed revert D100625.

Reviewed By: usaxena95

Differential Revision: https://reviews.llvm.org/D101851

This hinders translations, as per:
https://clang.llvm.org/docs/InternalsManual.html#the-format-string

Reviewed By: MaskRay, xbolva00

Differential Revision: https://reviews.llvm.org/D101387

PR50160: we currently ignore non-PT_PHDR segments with no sections, not
accounting for its p_offset and p_filesz: this can cause an out-of-bounds write
in `writeSegmentData` if the p_offset+p_filesz is larger than the total file
size.

This can be fixed by setting p_offset=p_filesz=0. The logic nicely unifies with
the logic added in D90897.

Reviewed By: jhenderson, rupprecht

Differential Revision: https://reviews.llvm.org/D101560

This corrects a few issues identified by `clang-format`.  This is meant
to be preparation for a subsequent change.

This untangles the MCContext and the MCObjectFileInfo. There is a circular
dependency between MCContext and MCObjectFileInfo. Currently this dependency
also exists during construction: You can't contruct a MOFI without a MCContext
without constructing the MCContext with a dummy version of that MOFI first.
This removes this dependency during construction. In a perfect world,
MCObjectFileInfo wouldn't depend on MCContext at all, but only be stored in the
MCContext, like other MC information. This is future work.

This also shifts/adds more information to the MCContext making it more
available to the different targets. Namely:

- TargetTriple
- ObjectFileType
- SubtargetInfo

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D101462

LoopVectorize has a fairly deeply baked in design problem where it will try to query analysis (primarily SCEV, but also ValueTracking) in the midst of mutating IR. In particular, the intermediate IR state does not represent the semantics of the original (or final) program.

Fixing this for real is hard, but all of the cases seen so far share a common symptom. In cases seen to date, the analysis being queried is the computation of the original loop's trip count. We can fix this particular instance of the issue by simply computing the trip count early, and caching it.

I want to be really clear that this is nothing but a workaround. It does nothing to fix the root issue, and at best, delays the time until we have to fix this for real. Florian and I have discussed an eventual solution in the review comments for https://reviews.llvm.org/D100663, but it's a lot of work.

Test taken from https://reviews.llvm.org/D100663.

Differential Revision: https://reviews.llvm.org/D101487

These instructions map to SVE-specific instrinsics that accept a
predicate operand to support control flow in vector code.

Differential Revision: https://reviews.llvm.org/D100982

This cleaned up an oversight over a year ago. Should no longer be needed.

This patch adds support for vectorizing loops with 'iter_args'
implementing known reductions along the vector dimension. Comparing to
the non-vector-dimension case, two additional things are done during
vectorization of such loops:
- The resulting vector returned from the loop is reduced to a scalar
  using `vector.reduce`.
- In some cases a mask is applied to the vector yielded at the end of
  the loop to prevent garbage values from being written to the
  accumulator.

Vectorization of reduction loops is disabled by default. To enable it, a
map from loops to array of reduction descriptors should be explicitly passed to
`vectorizeAffineLoops`, or `vectorize-reductions=true` should be passed
to the SuperVectorize pass.

Current limitations:
- Loops with a non-unit step size are not supported.
- n-D vectorization with n > 1 is not supported.

Reviewed By: nicolasvasilache

Differential Revision: https://reviews.llvm.org/D100694

CGProfilePass is not always on, it will be disabled when using
non-intergrated assemblers.

  // Only enable CGProfilePass when using integrated assembler, since
  // non-integrated assemblers don't recognize .cgprofile section.
  PMBuilder.CallGraphProfile = !CodeGenOpts.DisableIntegratedAS;

Add -fintegrate-as to make sure the output don't rely on the platform default.

Reviewed By: evgeny777

Differential Revision: https://reviews.llvm.org/D101918

Reviewed By: xgupta, amccarth

Differential Revision: https://reviews.llvm.org/D101433

Added details about the llvm/example section.

Reviewed By: xgupta

Differential Revision: https://reviews.llvm.org/D101284

Revert "[SelectionDAG][Mips][PowerPC][RISCV][WebAssembly] Teach computeKnownBits/ComputeNumSignBits about atomics"

This seems to have broken sanitizers, giving lots of

  Assertion `NumBits <= MAX_INT_BITS && "bitwidth too large"' failed.

failures across multiple targets (currently X86 and PowerPC). Reverting
until I have a chance to reproduce and debug.

This reverts commit 6e876f9d.

Current implementation defines LIBC_TARGET_MACHINE with the use of CMAKE_SYSTEM_PROCESSOR.
Unfortunately CMAKE_SYSTEM_PROCESSOR is OS dependent and can produce different results.
An evidence of this is the various matchers used to detect whether the architecture is x86.

This patch normalizes LIBC_TARGET_MACHINE and renames it LIBC_TARGET_ARCHITECTURE.
I've added many architectures but we may want to limit ourselves to x86 and ARM.

Differential Revision: https://reviews.llvm.org/D101524

[SelectionDAG][Mips][PowerPC][RISCV][WebAssembly] Teach computeKnownBits/ComputeNumSignBits about atomics

Unlike normal loads these don't have an extension field, but we know
from TargetLowering whether these are sign-extending or zero-extending,
and so can optimise away unnecessary extensions.

This was noticed on RISC-V, where sign extensions in the calling
convention would result in unnecessary explicit extension instructions,
but this also fixes some Mips inefficiencies. PowerPC sees churn in the
tests as all the zero extensions are only for promoting 32-bit to
64-bit, but these zero extensions are still not optimised away as they
should be, likely due to i32 being a legal type.

This also simplifies the WebAssembly code somewhat, which currently
works around the lack of target-independent combines with some ugly
patterns that break once they're optimised away.

Reviewed By: RKSimon, atanasyan

Differential Revision: https://reviews.llvm.org/D101342

Fix a bug where buildZExtInReg will create and use a new register instead of using the register from parameter DstOp Res.

Reviewed By: arsenm, foad

Differential Revision: https://reviews.llvm.org/D101871

Simplifies an upcoming patch diff