This is a bugfix patch that resolves the following two bugs in loop interchange:

1. PR57148 which is an assertion error due to of loss of LCSSA form after interchange,
   as referred to test1() in pr57148.ll.
2. Use before def for the outermost loop induction variables after interchange,
   as referred to test2() in pr57148.ll.

The fix in this patch is that:

1. In cases where the LCSSA form is not maintained after interchange, we update the IR
   to the LCSSA form again.
2. We split the phi nodes in the inner loop header into a separate basic block to avoid
   the situation where use of the outer indvar appears before its def after interchange.
   Previously we already did this for innermost loops, now we do it for non-innermost
   loops (e.g., middle loops) as well.

Reviewed By: bmahjour, Meinersbur, #loopoptwg

Differential Revision: https://reviews.llvm.org/D132055

Use load32_zero instead of load32_splat to load the low 32 bits from memory to
v128. Test cases are added to cover this change.

Reviewed By: tlively

Differential Revision: https://reviews.llvm.org/D134257

This patch is to resolve the bug reported and discussed in
https://reviews.llvm.org/D124926#3718761 and https://reviews.llvm.org/D124926#3719876.

The problem is that loop interchange is a loopnest pass under the new pass manager,
but the loop nest may not be constructed correctly by the loop pass manager after
running loop interchange and before running the next pass, which might cause problems
when it continues running the next pass.

The reason that the loop nest is constructed incorrectly is that the outermost
loop might have changed after interchange, and what was the original outermost
loop is not the current outermost loop anymore. Constructing the loop nest based
on the original outermost loop would generate an invalid loop nest.

The fix in this patch is that, in the loop pass manager before running each loopnest
pass, we re-cosntruct the loop nest based on the current outermost loop, if LPMUpdater
notifies the loop pass manager that the previous loop nest has been invalidated by passes
like loop interchange.

Reviewed By: aeubanks

Differential Revision: https://reviews.llvm.org/D132199

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D134164

implement the option2 of P2014R0

This implements the option2 of
https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2020/p2014r0.pdf.

This also fixes https://github.com/llvm/llvm-project/issues/56671.

Although wg21 didn't get consensus for the direction of the problem,
we're happy to have some implementation and user experience first. And
from issue56671, the option2 should be the pursued one.

Reviewed By: ychen

Differential Revision: https://reviews.llvm.org/D133341

Unicode 15.0 adds 4,489 characters, for a total of 149,186 characters.
These additions include 2 new scripts along with 20 new emoji characters,
and 4,193 CJK ideographs.

This changes modify most existing tables including
 - XID_Start/XID_Continue in Clang
 - The character name database (used by \N{} in Clang)
 - The list of formattable/printable codepoints
 - The case folding algorithm (which we had not updated since Unicode 9)
 - The list of nonspacing/enclosing marks used by the column width
   computation algorithm. The rest of the column width algorithm
   is not updated.

Reviewed By: tahonermann

Differential Revision: https://reviews.llvm.org/D133807

Specifically predicates for extensions that are subsets of other
extensions. These predicates should never be used. Should always
check the superset extension or the superset ORed with the sub extendsion.

This allows for incrementally updating the old API usages without
needing to update everything at once. PDL will be left on Both
for a little bit and then flipped to prefixed when all APIs have been
updated.

Differential Revision: https://reviews.llvm.org/D134387

This allows for incrementally updating the old API usages without
needing to update everything at once. These will be left on Both
for a little bit and then flipped to prefixed when all APIs have been
updated.

Differential Revision: https://reviews.llvm.org/D134386

showBRParamDiagnostics assumed stores happen only via function parameters while that
can also happen via implicit parameters like 'self' or 'this'.
The regression test caused a failed assert in the original cast to ParmVarDecl.

Differential Revision: https://reviews.llvm.org/D133815

Instrumentation just ORs shadow of inputs.
I assume some result shadow bits can be reset if we go into specifics of particular checks,
but as-is it is still an improvement against existing default strict instruction handler, when
every set bit of input shadow is  reported as an error.

Reviewed By: kda

Differential Revision: https://reviews.llvm.org/D134123

CWD may be read-only in some testing environments.

Write a semantics test for the atomic intrinsic subroutine,
atomic_xor.

Reviewed By: rouson

Differential Revision: https://reviews.llvm.org/D134298

We have namespaces `DXIL` and `dxil`, which is just confusing. This
renames `DXIL` -> `dxil` making everything consistent.

While the LLVM coding standards don't have a clear direction here, I
chose lower case because by my current unscientific count there are
more places where we had the lowercase namespace than the uppercase.

When `objc_direct` methods were implemented, the implicit `_cmd` parameter was left as an argument to the method implementation function, but was unset by callers; if the method body referenced the `_cmd` variable, a selector load would be emitted inside the body. However, this leaves an unused argument in the ABI, and is unnecessary.

This change removes the empty/unset argument, and if `_cmd` is referenced inside an `objc_direct` method it will emit local storage for the implicit variable. From the ABI perspective, `objc_direct` methods will have the implicit `self` parameter, immediately followed by whatever explicit arguments are defined on the method, rather than having one unset/undefined register in the middle.

Differential Revision: https://reviews.llvm.org/D131424

Name them after the instructions VFCVT_RTZ_X(U)_F_VL to make it
clear that the ISD nodes don't have the poison semantics of
ISD::SINT_TO_FP/UINT_TO_FP.

I play to reuse this node for a FP_TO_SINT_SAT/FP_TO_UINT_SAT
patch and need the instruction semantics.

Removed FIXME which looks irrelevant. The error message happens only without -mattr=+avx.
E.g.
GOOD: opt llvm/test/Instrumentation/MemorySanitizer/avx-intrinsics-x86.ll -passes=msan -o - | llc -O3 -o /dev/null -mattr=+avx
BAD: opt llvm/test/Instrumentation/MemorySanitizer/avx-intrinsics-x86.ll -passes=msan -o - | llc -O3 -o /dev/null

So nothing to fix here.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D134119

Differential Revision: https://reviews.llvm.org/D134153

Once we create an instance of InlineCost, we don't change its
contents.

Differential Revision: https://reviews.llvm.org/D134388

We were recognizing vectors of floats, but not scalars.  That's a tad odd.

[Hexagon] Fix -Wunused-variable in non-assertion builds after f6e7ad56

Tested with the following program:

```
static volatile int* x = nullptr;

void throws()  __attribute__((noinline)) {
  if (getpid() == 0)
    return;
  throw "error";
}

void maybe_throws()  __attribute__((noinline)) {
  volatile int y = 1;
  x = &y;
  throws();
  y = 2;
}

int main(int argc, char** argv) {
  int y;
  try {
    maybe_throws();
  } catch (const char* e) {
    //printf("Caught\n");
  }
  y = *x;
  printf("%d\n", y); // should be MTE failure.
  return 0;
}
```

Built using `clang++ -c -O2 -target aarch64-linux -fexceptions -march=armv8-a+memtag -fsanitize=memtag-heap,memtag-stack`

Currently only Android implements runtime support for MTE stack tagging.

Without this change, we crash on `__cxa_get_globals` when trying to catch
the exception (because the stack frame __cxa_get_globals frame will fail due
to tags left behind on the stack). With this change, we crash on the `y = *x;`
as expected, because the stack frame has been untagged, but the point...

This option specifies a GCC installation directory such as
/usr/lib/gcc/x86_64-linux-gnu/12, /usr/lib/gcc/x86_64-gentoo-linux-musl/11.2.0 .

It is intended to replace --gcc-toolchain=, which specifies a directory where
`lib/gcc{,-cross}` can be found. When --gcc-toolchain= is specified, the
selected `lib/gcc/$triple/$version` installation uses complex logic and the
largest GCC version is picked. There is no way to specify another version in the
presence of multiple GCC versions.

D25661 added gcc-config detection for Gentoo: `ScanGentooConfigs`.
The implementation may be simplified by using --gcc-install-dir=.

Reviewed By: mgorny

Differential Revision: https://reviews.llvm.org/D133329

This validation was introduced in D34003 for v_qsad/v_mqsad instructions
but it applies to all instructions with earlyclobber operands, which now
includes v_mad_i64/v_mad_u64.

In all these cases I do not think there is documentation saying that the
destination must not overlap the sources. Rather there are *some* cases
where the instruction may not function correctly if there is an overlap,
and we are using earlyclobber as a conservative way of preventing
codegen from generating those cases.

I think it is unhelpful for the assembler to enforce the earlyclobber
restriction because it prevents assembling cases where the programmer
knows that in fact the overlap is safe.

See also: https://github.com/llvm/llvm-project/issues/57610

Differential Revision: https://reviews.llvm.org/D134272

I don't know what was going on originally with these tests. It seems reasonable
to have the immediate be the same byte alignment unit as the IR, in which case
we need to take the log2 in order to set the right number of low bits.

This fixes a miscompile in chromium.

Differential Revision: https://reviews.llvm.org/D134380

Also add a .clang-format file to clang/include/clang/Format and
clang/unittests/Format to keep the directories formatted.

This reverts commit 411020ad.

One of the tests here fails on some upstream builders:
https://lab.llvm.org/buildbot#builders/16/builds/35314

Direct continuation of https://reviews.llvm.org/D133887

Reviewed By: #clang-language-wg, aaron.ballman

Differential Revision: https://reviews.llvm.org/D134207

See https://github.com/llvm/llvm-project/issues/57815.

dso_local_equivalent would fail with an assertion on forward-referenced
globals. This is an issue that only comes up in textual IR, which is why
we've never seen this assertion with clang.

Differential Revision: https://reviews.llvm.org/D134234

Lib profile could include all kind of entry functions.

Reviewed By: beanz

Differential Revision: https://reviews.llvm.org/D134326

`(A * -2**C) + B --> B - (A << C)`

https://alive2.llvm.org/ce/z/A6BWkf

This inverts what Negator was doing before:
D134310 / 0f32a5de

Analysis and codegen are generally better without multiply,
so we should favor this form even if we trade add for sub
(because those are generally equivalent cost operations).

Fix braces and add .clang-format to keep the directory formatted.

Differential Revision: https://reviews.llvm.org/D134329

This code was added in b65b1f32, but it
was not noticed that the [[fallthrough]] behavior was very wrong. In C
mode, we would set the ParenExprType to CompoundLiteral and then
promptly overwrite that information by falling through.

After some investigation, I convinced myself that it is not possible to
hit this code path in C, only in C++. I've switched it to be an
assertion; I don't expect to hit it, but if we do hit it, that will at
least give us a code example we can use to reason about the intent of
the original code.