[X86] combineAndnp - if an input has a zero (after inversion for Op0) in a vector element, then we don't demand that bit/element in the other input

Similar to what we already perform in combineAnd

Reg unit sets are uniqued, so no need to wrap it in a set.

I have not found a way to expose a difference for this patch in a test
because it only triggers for a one-use load, but this is the code that
was adapted into D118376 and caused miscompiles. The new code pattern
is the same as what we do in narrowExtractedVectorLoad() (reduces load
width for a subvector extract).

This removes seemingly unnecessary manual worklist management and fixes
the chain updating via "SelectionDAG::makeEquivalentMemoryOrdering()".

Differential Revision: https://reviews.llvm.org/D119549

Extend the existing fold to use SimplifyMultipleUseDemandedBits as well as SimplifyDemandedVectorElts/SimplifyDemandedBits when attempting to simplify based off known zero vector elements.

To find uniform shift/rotation amounts, we currently use SelectionDAG::getSplatValue which creates a node that extracts the scalar value from the source vector, this makes it more difficult for later combines to remove the extraction and stay on the SIMD unit, and can be a problem when the scalar type is illegal (i.e. i64 vs v2i64 on 32-bit targets).

This patch begins to use SelectionDAG::getSplatSourceVector (which SelectionDAG::getSplatValue uses internally) and adds a new variant of getTargetVShiftNode that takes the source vector and the splat index, and adjusts the vector in place to create the zero-extended value suitable for the SSE PSLL/PSRL/PSRA uniform instructions.

I'm still addressing a number of regressions when used for normal vector shifts, so I've just handled the funnelshift/rotation lowering for this first patch. I can then focus on the yak shaving (SimplifyDemandedBits/Elts in particular) necessary to always use SelectionDAG::getSplatSourceVector.

Differential Revision: https://reviews.llvm.org/D119090

Apparently modern versions of ounit2 can only be found as "ounit2"
rather than "oUnit" version 2.  Update the CMake check to support both
variants.  This makes the OCaml tests run again with ounit2-2.2.4.

Differential Revision: https://reviews.llvm.org/D119079

A significant number of our tests in C accidentally use functions
without prototypes. This patch converts the function signatures to have
a prototype for the situations where the test is not specific to K&R C
declarations. e.g.,

  void func();

becomes

  void func(void);

This is the eighth batch of tests being updated (there are a
significant number of other tests left to be updated).

Just use dyn_cast<> to determine literal + container values from the binop

[clang-doc] populateParentNamespaces - use cast<> instead of dyn_cast<> to avoid dereference of nullptr

The pointer is referenced immediately, so assert the cast is correct instead of returning nullptr

It's only later iterations of the loop where the getParent() call might return nullptr

The pointer is referenced immediately, so assert the cast is correct instead of returning nullptr

[clang][sema] Sema::CheckFreeArguments - use cast<> instead of dyn_cast<> to avoid dereference of nullptr

The pointer is referenced immediately, so assert the cast is correct instead of returning nullptr

The pointer is referenced immediately, so assert the cast is correct instead of returning nullptr

[clang-tidy] RedundantControlFlowCheck::issueDiagnostic - use cast<> instead of dyn_cast<> to avoid dereference of nullptr

The pointer is referenced immediately, so assert the cast is correct instead of returning nullptr

[clang-tidy] FunctionASTVisitor::TraverseStmt - use cast<> instead of dyn_cast<> to avoid dereference of nullptr

The pointer is referenced immediately, so assert the cast is correct instead of returning nullptr

[clang-tidy] NoexceptMoveConstructorCheck::check - use castAs<> instead of getAs<> to avoid dereference of nullptr

The pointer is referenced immediately, so assert the cast is correct instead of returning nullptr

[clang-tidy] UseNoexceptCheck::check - use cast<> instead of dyn_cast<> to avoid dereference of nullptr

The pointer is referenced immediately, so assert the cast is correct instead of returning nullptr

The pointer is always dereferenced

[clang-tidy] ProBoundsConstantArrayIndexCheck::check - use cast<> instead of dyn_cast<> to avoid dereference of nullptr

The pointer is referenced immediately, so assert the cast is correct instead of returning nullptr

[clang-tidy] checkOverridingFunctionReturnType - use castAs<> instead of getAs<> to avoid dereference of nullptr

The pointers are referenced immediately, so assert the cast is correct instead of returning nullptr

Revert "Reland "[lld/coff] Make lld-link work in a non-MSVC shell, add /winsysroot:""

This reverts commit 0574b5fc and 73e585e4.

This change is causing the test Driver/cl-options.c to fail on Windows buildbots.
https://lab.llvm.org/staging/#/builders/204/builds/1343

A LUI instruction with flag RISCVII::MO_HI is usually used in conjunction
with ADDI, and jointly complete address computation. To bind the cost
evaluation of address computation, the LUI should not be regarded as a cheap
 move separately, which is consistent with ADDI.

In this test case, it improves the unroll-loop code that the rematerialization
of array's base address miss MachineCSE with Heuristics #1 at isProfitableToCSE.

Reviewed By: asb, frasercrmck

Differential Revision: https://reviews.llvm.org/D118216

Reviewed By: asb, frasercrmck

Differential Revision: https://reviews.llvm.org/D118218

By unsetting this property, we are now able to internalize more symbols
during LTO. I compared the output of `-save-temps` for both LLD and
ld64, and we now match ld64's behavior as far as `lto-internalize.ll` is
concerned.

(Thanks @smeenai for working on an initial version of this diff!)

Fixes https://github.com/llvm/llvm-project/issues/50574.

Reviewed By: #lld-macho, thakis

Differential Revision: https://reviews.llvm.org/D119372

Implements ADDS/SUBS 24-bit immediate optimization using the
MIPeepholeOpt pass. This follows the pattern:

Optimize ([adds|subs] r, imm) -> ([ADDS|SUBS] ([ADD|SUB] r, #imm0, lsl #12), #imm1),
if imm == (imm0<<12)+imm1. and both imm0 and imm1 are non-zero 12-bit unsigned
integers.

Optimize ([adds|subs] r, imm) -> ([SUBS|ADDS] ([SUB|ADD] r, #imm0, lsl #12), #imm1),
if imm == -(imm0<<12)-imm1, and both imm0 and imm1 are non-zero 12-bit unsigned
integers.

The SplitAndOpcFunc type had to change the return type to an Opcode pair so that
the first add/sub is the regular instruction and the second is the flag setting
instruction. This required updating the code in the AND case.

Testing:

I ran a two stage bootstrap with this code.
Using the second stage compiler, I verified that the negation of an ADDS to SUBS
or vice versa is a valid optimization. Example V == -0x111111.

Reviewed By: dmgreen

Differential Revision: https://reviews.llvm.org/D118663

Move some combine patterns to DAG combine，and
it dealt with fixme left in RISCVInstrInfoZb.td.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D119527

Reviewed By: browneee

Differential Revision: https://reviews.llvm.org/D119606

It is generally an error when a USE-associated name clashes
with a name defined locally, but not in all cases; a generic
interface can be both USE-associated and locally defined.
This works, but not when there is also a local subprogram
with the same name, which is valid when that subprogram is
a specific of the local generic.  A bogus error issues at
the point of the USE because name resolution will have already
defined a symbol for the local subprogram.

The solution is to collect the names of local generics when
creating the program tree, and then create their symbols as
well if their names are also local subprograms, prior to any
USE association processing.

Differential Revision: https://reviews.llvm.org/D119566

We are just grouping the files and the tests together.

Reviewed By: int3, #lld-macho

Differential Revision: https://reviews.llvm.org/D119456

This diff has the C-string literals printed into the mapfile in the symbol table like how ld64 does.

Here is what ld64's mapfile looks like with C-string literals:
```
# Path: out
# Arch: x86_64
# Object files:
[  0] linker synthesized
[  1] foo.o
# Sections:
# Address       Size            Segment Section
0x100003F7D     0x0000001D      __TEXT  __text
0x100003F9A     0x0000001E      __TEXT  __cstring
0x100003FB8     0x00000048      __TEXT  __unwind_info
# Symbols:
# Address       Size            File  Name
0x100003F7D     0x0000001D      [  1] _main
0x100003F9A     0x0000000E      [  1] literal string: Hello world!\n
0x100003FA8     0x00000010      [  1] literal string: Hello, it's me\n
0x100003FB8     0x00000048      [  0] compact unwind info
```

Here is what the new lld's Mach-O mapfile looks like:
```
# Path: /Users/rgr/local/llvm-project/build/Debug/tools/lld/test/MachO/Output/map-file.s.tmp/c-string-liter
al-out
# Arch: x86_64
# Object files:
[  0] linker synthes...

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D119503

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D119498