Changes

[llvm-readobj/elf] - Simplify and refine the implementation which dumps .stack_sizes

Our implementation of stack sizes section dumping heavily uses `ELFObjectFile<ELFT>`,
while the rest of the code uses `ELFFile<ELFT>`.

That APIs are very different. `ELFObjectFile<ELFT>` is very generic
and has `SectionRef`, `RelocationRef`, `SymbolRef` and other generic concepts.
The `ELFFile<ELFT>` class works directly with `Elf_Shdr`, `Elf_Rel[a]`, `Elf_Sym` etc,
what is probably much cleaner for ELF dumper.

Also, `ELFObjectFile<ELFT>` API does not always provide a way to check
for possible errors. E.g. the implementation of `symbol_end()` does not verify the `sh_size`:

```
template <class ELFT>
basic_symbol_iterator ELFObjectFile<ELFT>::symbol_end() const {
  const Elf_Shdr *SymTab = DotSymtabSec;
  if (!SymTab)
    return symbol_begin();
  DataRefImpl Sym = toDRI(SymTab, SymTab->sh_size / sizeof(Elf_Sym));
  return basic_symbol_iterator(SymbolRef(Sym, this));
}
```
There are many other examples which makes me thing we might win from
switching to `ELFFile<ELFT>` API, where we heavily validate an input data already.

This patch is the first step in this direction. I've converted the large portion of the code
to use `ELFFile<ELFT>`.

Differential revision: https://reviews.llvm.org/D87362

[X86] detectAVGPattern - accept non-pow2 vectors by padding.

Drop the pow2 vector limitation for AVG generation by padding the vector to the next pow2, creating the PAVG nodes and then extracting the final subvector.

Fixes some poor codegen that has been annoying me for years.....

[MVE] fix typo in llvm debug message. NFC.

[Transforms][Coroutines] Add missing header path to CMakeLists.txt

Helps Visual Studio check include dependencies.

[SelectionDAG] Remove unused FP constant in getNegatedExpression

960cbc53 immediately removes nodes that won't be used to avoid
compilation time explosion. This patch adds the removal to constants to
fix PR47517.

Reviewed By: RKSimon, steven.zhang

Differential Revision: https://reviews.llvm.org/D87614

[ARM] Corrected condition in isSaturatingConditional

Fixed a small error in an if condition to prevent usat/ssat being generated if (upper constant + 1) is not a
power of 2.

[X86] Update SSE/AVX integer MINMAX intrinsics to emit llvm.smax.* etc. (PR46851)

We're now getting close to having the necessary analysis/combines etc. for the new generic llvm smax/smin/umax/umin intrinsics.

This patch updates the SSE/AVX integer MINMAX intrinsics to emit the generic equivalents instead of the icmp+select code pattern.

Differential Revision: https://reviews.llvm.org/D87603

Revert "[InstCombine] Simplify select operand based on equality condition"

This reverts commit cfff88c03cf9e9b72906a41fd11e06721d54f293. Sends
instcombine into an infinite loop.

```
define i1 @foo(i32 %arg, i32 %arg1) {
bb:
  %tmp = udiv i32 %arg, %arg1
  %tmp2 = mul nsw i32 %tmp, %arg1
  %tmp3 = icmp eq i32 %tmp2, %arg
  %tmp4 = select i1 %tmp3, i32 %tmp, i32 undef
  %tmp5 = icmp sgt i32 %tmp4, 255
  ret i1 %tmp5
}
```

[mlir][integration_test] Linalg Conv folder renamed to CPU

Changing directory name to reflect naming convention discussed here:
https://llvm.discourse.group/t/vectorops-rfc-add-suite-of-integration-tests-for-vector-dialect-operations/1213

Differential Revision: https://reviews.llvm.org/D87678

[mlir] check for failures when packing function sigunatures in std->llvm conversion

When packing function results into a structure during the standard-to-llvm
dialect conversion, do not assume the conversion was successful and propagate
nullptr as error state.

Fixes PR45184.

Reviewed By: nicolasvasilache

Differential Revision: https://reviews.llvm.org/D87605

Recommit "[ConstraintSystem] Add helpers to deal with linear constraints."

This patch recommits "[ConstraintSystem] Add helpers to deal with linear constraints."
(it reverts the revert commit 8da6ae4ce1b686c5c13698e4c5ee937811fda6f7).

The reason for the revert was using __builtin_multiply_overflow, which
is not available for all compilers. The patch has been updated to use
MulOverflow from MathExtras.h

SelectionDAGBuilder.h - remove unnecessary includes. NFCI.

Reduce to forward declarations and move implicit dependencies down to the cpp files.

StatepointLowering.cpp - remove unnecessary includes. NFCI.

These are all directly included in StatepointLowering.h

SpillPlacement.cpp - remove unnecessary includes. NFCI.

These are all directly included in SpillPlacement.h

Revert "RegAllocFast: Record internal state based on register units"

This seems to have caused incorrect register allocation in some cases,
breaking tests in the Zig standard library (PR47278).

As discussed on the bug, revert back to green for now.

> Record internal state based on register units. This is often more
> efficient as there are typically fewer register units to update
> compared to iterating over all the aliases of a register.
>
> Original patch by Matthias Braun, but I've been rebasing and fixing it
> for almost 2 years and fixed a few bugs causing intermediate failures
> to make this patch independent of the changes in
> https://reviews.llvm.org/D52010.

This reverts commit 66251f7e1de79a7c1620659b7f58352b8c8e892e, and
follow-ups 931a68f26b9a3de853807ffad7b2cd0a2dd30922
and 0671a4c5087d40450603d9d26cf239f1a8b1367e. It also adjust some
test expectations.

[lldb/cmake] Fix testing support library dependencies

lldbUtilityHelpers does not depend on lldbSymbolHelpers. Remove that
dependency, and add direct lldbSymbolHelpers dependencies where needed.

[lldb] Improve qemu interop for aarch64

qemu calls the "fp" and "lr" registers via their generic names
(x29/x30). This mismatch manifested itself as not being able to unwind
or display values of some local variables.