Cycle is associated with construct-names and not labels. Change name of
a few variables to reflect this. Also add appropriate comment to
describe the else case of error checking.

With the commit d5308949, we now
preserve the initializer for invalid decls with the recovery-expr.

However there is a chance that the original init expr is a typo-expr, we
should not preserve it in the final AST, as typo-expr is an internal AST
node. We should use the one after the typo correction.

This is spotted by a clangd hover crash on the testcase.

-- This commit adds a canonicalization pattern to fold away iter args of
scf.forall if :-
   a. The corresponding tied result has no use.
   b. It is not being modified within the loop.

Signed-off-by: Abhishek Varma <avarma094@gmail.com>

... even if the storage types are different.

Demonstrate that this isn't yet working right.

The test fails after dfa7ff97. I didn't find this locally due to
cache.

look through shuffle vectors

* This way the helper function could be re-used by
indirect-call-promotion pass to find out the vtable for an indirect call
and extract the value profiles if any.
* The parent patch is https://github.com/llvm/llvm-project/pull/80762

into the current module

Following of https://github.com/llvm/llvm-project/pull/86912. After
https://github.com/llvm/llvm-project/pull/86912, with reduced BMI, the
BMI can keep unchange if the dependent modules only changes the
implementation (without introduing new decls). However, this is not
strictly correct.

For example:

```
// a.cppm
export module a;
export inline int a() { ... }

// b.cppm
export module b;
import a;
export inline int b() { return a(); }
```

Since both `a()` and `b()` are inline, we need to make sure the BMI of
`b.pcm` will change after the implementation of `a()` changes.

We can't get that naturally since we won't record the body of `a()`
during the writing process. We can't reuse ODRHash here since ODRHash
won't calculate the called function recursively. So ODRHash will be
problematic if `a()` calls other inline functions.

Probably we can solve this by a new hash mechanism. But the safety and
efficiency may a problem too. Here we just combine the hash value of the
used modules conservatively.

of elements

Close https://github.com/llvm/llvm-project/issues/91105

The root reason for the issue is that we always generate the
dependently-sized array types which don't specify a number of elements.

The original comment says:

> We do no canonicalization here at all, which is okay
> because they can't be used in most locations.

But now we find the locations.

Also adds AllowShortCaseExpressionOnASingleLine option and
AlignCaseArrows suboption of AlignConsecutiveShortCaseStatements.

Fixes #55903.

First step for #64840.

This patch adds basic codegen support for Zvfbfmin extension.

Summary:
This patch removes the special-case handling for the target triple
inside of the CMake. I moved it into the implementation so it's easier
to see and modify.

Revert "[DirectX][DXIL] Set DXIL Version in DXIL target triple based on shader model version" (#91290)

Reverts llvm/llvm-project#90809

Need to investigate ASAN failures.

Fold
``` llvm
define i64 @src(i64 %50) {
  %52 = lshr i64 -1, %50
  %53 = add i64 %52, 1
  %54 = call i64 @llvm.cttz.i64(i64 %53, i1 false)
  ret i64 %54
}
```
to
``` llvm
define i64 @tgt(i64 %50) {
  %52 = sub i64 64, %50
  ret i64 %52
}
```

as
https://github.com/llvm/llvm-project/pull/91171#pullrequestreview-2040663002
pointed out.

Alive2 proof: https://alive2.llvm.org/ce/z/2aHfYa

Note: the `ctlz` version of this pattern seems not exist in dtcxzyw's
benchmark, so put it aside for now.

There is a missed optimization in
``` llvm
define i8 @known_power_of_two_rust_next_power_of_two(i8 %x, i8 %y) {
  %2 = add i8 %x, -1
  %3 = tail call i8 @llvm.ctlz.i8(i8 %2, i1 true)
  %4 = lshr i8 -1, %3
  %5 = add i8 %4, 1
  %6 = icmp ugt i8 %x, 1
  %p = select i1 %6, i8 %5, i8 1

  %r = urem i8 %y, %p
  ret i8 %r
}
```
which is extracted from the Rust code
``` rust
fn func(x: usize, y: usize) -> usize {
    let z = x.next_power_of_two();
    y % z
}
```
Here `%p` (a.k.a `z`) is semantically a power-of-two, so `y urem p` can
be optimized to `y & (p - 1)`. (Alive2 proof:
https://alive2.llvm.org/ce/z/H3zooY)

---

It could be generalized to recognizing `LShr(UINT_MAX, Y) + 1` as a
power-of-two, which is what this PR does.
Alive2 proof: https://alive2.llvm.org/ce/z/zUPTbc

For inbounds GEPs, if the source pointer is non-null, the result must
also be non-null. However, this does not hold for non-inbounds GEPs.
    
Fixes https://github.com/llvm/llvm-project/issues/91177.

Originally, the callbr result could only be used on the fallthrough
destination. This limitation has been lifted, and the result is now also
available on the indirect destinations. However, LangRef was not updated
to reflect this.

Revert "[coro][CoroSplit] Use `llvm.lifetime.end` to compute putting objects on the frame vs the stack (#90265)"

This reverts commit fcf341d3.

Causes major compile-time regressions when not using coroutines.

Currently in `ObjcCategoryMerger::doMerge` and
`generateCatListForNonErasedCategories` we use maps of pointers which
leads to non-determinism. Switch instead to using `MapVector` which
preserves determinism.

Fixes an inactive check line and updates the check to match output and
other cases.

[webkit.RefCntblBaseVirtualDtor] Ignore WTF::RefCounted<T> and its variants missing virtual destructor (#91009)

stdarg.h and especially stddef.h are textual and so everything they
declare gets precompiled into all of their clients' pcm files. They
shouldn't directly declare anything though, their purpose is to select
what submodules get imported, and not to add duplicate declarations to
all of their clients. Make it so that they always ignore their header
guards, even without modules, and declare them in separate header files
so that they only go into the stdarg/stddef pcms. Still declare them in
case clients rely on them.

Such APIs are useful in lock implementations

fir.cuda_free operation was wrongly generated for dummy argument.

An earlier commit provided a way to decouple DXIL version from Shader
Model version by representing the DXIL version as `SubArch` in the DXIL 
Target Triple and adding corresponding valid DXIL Arch types.

This change constructs DXIL target triple with DXIL version that is
deduced from Shader Model version specified in the following scenarios:

1. When compilation target profile is specified: 
For e.g., DXIL target triple `dxilv1.8-unknown-shader6.8-library` is
constructed when `-T lib_6_8` is specified. 
2. When DXIL target triple without DXIL version is specified:
For e.g., DXIL target triple `dxilv1.8-pc-shadermodel6.8-library` is
constructed when `-mtriple=dxil-pc-shadermodel6.8-library` is specified.

Updated relevant HLSL tests that check for target triple. 

Validated that Clang (`check-clang`) and LLVM (`check-llvm`) regression
tests pass.

Address review comments for PR91214.

Use add_custom_command instead of add_custom_target to generate
SBLanguages.h.

This implements the HLSL 202x conforming literals feature.

The feature proposal is available here:

https://github.com/microsoft/hlsl-specs/blob/main/proposals/0017-conforming-literals.md

The language specification for this behavior is available in (poorly
rendered) HTML or PDF:
https://microsoft.github.io/hlsl-specs/specs/hlsl.html#Lex.Literal.Float
https://microsoft.github.io/hlsl-specs/specs/hlsl.pdf

The main implementation details are:
1) Unsuffixed floating literals are `float`.
2) The integer `ll` suffix specifies `int64_t (aka long)` which is
64-bit because HLSL has no defined `long` keyword or `long long` type.

Resolves #85714

This adds a document to describe the DXContainer format and the
structures of data inside the file.

Resolves #88775

Revert the portion of https://github.com/llvm/llvm-project/pull/75125
which modified the LIBOMP_HEADERS_INSTALL_PATH in standalone build.

This change is harmful for real standalone builds (i.e. builds where we
build openmp by itself), since it tries to overwrite the `omp.h` inside
the build compiler. For all-in-one builds with clang, testing shows this
change is unnecessary as https://github.com/llvm/llvm-project/pull/88007
already set up that build configuration so that omp.h will be put into
the project build's `clang` resource directory.

[coro][CoroSplit] Use `llvm.lifetime.end` to compute putting objects on the frame vs the stack (#90265)

The current logic for using lifetime intrinsics to determine whether a
coroutine alloca should live on the coroutine frame or stack doesn't
consider `llvm.lifetime.end`. As a result, some allocas are incorrectly
placed on the stack even though their lifetimes may outlive the stack.
For example, SimplifyCFG may generate code that drops the corresponding
`llvm.lifetime.end` of an `llvm.lifetime.start`, and that code is
incorrectly handled by the existing logic.

To fix this, new logic is introduced where if an alloca's address is
escaped, and there is a path from an `llvm.lifetime.start` to a
coroutine suspend point (e.g. `llvm.coro.suspend`) without an
`llvm.lifetime.end`, then we know the object lives beyond the suspension
point and therefore must go on the coroutine frame.

Fixes https://github.com/llvm/llvm-project/issues/86580

Insert the barrier after the last _executed_ copy, not the most recently
inserted copy.
This fixes https://github.com/llvm/llvm-project/issues/91205.

We need to update DW_AT_comp_dir/DW_AT_dwo_name TU in the
.debug_info.dwo section so that the path is correct. Refactored helper
functions to make it easier for next step.

This uses non-volatile registers for the first four (six on Windows)
registers used for `preserve_none` argument passing. This allows these
registers to stay "pinned", even if the body of the `preserve_none`
function contains calls to other "normal" functions.

Example:

```c
void boring(void);

__attribute__((preserve_none)) void (continuation)(void *, void *, void *, void *);

__attribute__((preserve_none)) void entry(void *a, void *b, void *c, void *d)
{
    boring();
    __attribute__((musttail)) return continuation(a, b, c, d);
}
``` 

Before:

```asm
pushq   %rax
movq    %rcx, %rbx
movq    %rdx, %r14
movq    %rsi, %r15
movq    %rdi, %r12
callq   boring@PLT
movq    %r12, %rdi
movq    %r15, %rsi
movq    %r14, %rdx
movq    %rbx, %rcx
popq    %rax
jmp     continuation@PLT
```

After:

```asm
pushq   %rax
callq   boring@PLT
popq    %rax
jmp     continuation@PLT
```