To simplify some code.

[X86] LowerBUILD_VECTOR - don't use insert_element(constant, elt, idx) if we have a freeze(undef) element

Fixes #74736

Treat a defined register as fully live "at" the instruction and update maximum pressure accordingly. Fixes #3786.

We have a bunch of folds that basically perform X pred Y to ~Y pred ~X
for various special cases where this saves an instruction.

Generalize these folds to use isFreeToInvert(). We have to make sure
that we consume an instruction in either of the inversions, otherwise
we're just going to swap the icmp back and forth.

Fixes https://github.com/llvm/llvm-project/issues/74302.

If we have vectorized variants of a function which take linear
parameters, we should be able to vectorize assuming the strides match.

The `expect_expr` check was introduced in
https://github.com/llvm/llvm-project/pull/74772. It is failing on Linux
and Windows, so skip this test to unblock the bots

opt accepts the -march command-line argument, but this argument only
makes sense in conjunction with -mtriple. Fix a couple of tests under
LoopVectorize that invoke opt with -march but without -mtriple, to avoid
confusing users.

The first couple of llc invocations mentioned in the document are wrong,
and users will get confused about no output being written. Fix them.

Declare `getPreservedProducerResults` function which helps to get the
preserved results of the producer linalg generic operation as a result
of elementwise fusion.

Reverts llvm/llvm-project#72713

Buildbot tests fail on clang-armv7-global-isel builder
https://lab.llvm.org/buildbot/#/builders/186/builds/13604

This MR fix the argument name of GEPOp builder from `basePtrType` to
`elementType` to avoid confusion.

Co-authored-by: Xiaolei Shi <xiaoleis@nvidia.com>

This patch continues the work started with ea5b1ef0. See that commit and its
corresponding PR for details.

This patch does the following simplifications:
```
cttz(shl(C, X), 1) -> add(cttz(C, 1), X)
cttz(lshr exact(C, X), 1) -> sub(cttz(C, 1), X)
ctlz(lshr(C, X), 1) --> add(ctlz(C, 1), X)
ctlz(shl nuw (C, X), 1) --> sub(ctlz(C, 1), X)
```
Alive2: https://alive2.llvm.org/ce/z/9KHlKc
Closes #41333

This patch adds llvm-readobj support for:

- Dynamic R_AARCH64_AUTH_* relocations (including RELR compressed AUTH
relocations) as described here:
https://github.com/ARM-software/abi-aa/blob/main/pauthabielf64/pauthabielf64.rst#auth-variant-dynamic-relocations

- .note.AARCH64-PAUTH-ABI-tag section as defined here
https://github.com/ARM-software/abi-aa/blob/main/pauthabielf64/pauthabielf64.rst#elf-marking

And add some patterns:
1. (fdiv 1.0, vector)
2. (fdiv 1.0, (fsqrt vector))

Apply clang-tidy fixes for llvm-prefer-isa-or-dyn-cast-in-conditionals in MapMemRefStorageClassPass.cpp (NFC)

[mlir][Transforms][NFC] GreedyPatternRewriteDriver: Remove redundant worklist management code (#74796)

Do not add the previous users of replaced ops to the worklist during
`notifyOperationReplaced`.

The previous users are modified inplace as part of
`PatternRewriter::replaceOp`, which calls
`PatternRewriter::replaceAllUsesWith`. The latter function updates all
users with `updateRootInPlace`, which already puts all previous users of
the replaced op on the worklist. No further worklist management work is
needed in the `notifyOperationReplaced` callback.

Identified with clangd.

Fix test initialization

This reverts commit d4136813.

Fix test array initialization.

When `sym` in `.reloc ., BFD_RELOC_NONE, sym` is not referenced
elsewhere, `sym` is not in the symbol table and the relocation
references the null symbol. Visit the expression to fix the issue.

Remove redundant initializations from pass constructors that were
already being initialized by LLVMInitializeRISCVTarget().

Also unifies some of the test set up parts in other conv tests

Add an extension feature `define-target-os-macros` that enables clang to
provide definitions of common TARGET_OS_* conditional macros. The
extension is enabled in the Darwin toolchain driver.

A few changes to HLSLExternalSemaSource and its BuiltinTypeDeclBuilder
to make defining buffer types less verbose. This will make it a lot
easier to see what the differences between the various buffer types
are once we start introducing more of them.

Pull Request: https://github.com/llvm/llvm-project/pull/73967