Changes

[clang] attempt to fix a linux test failure for the darwin-ld-platform-version-macos.c test

Clang should use explicit -target to ensure that the Darwin driver is used.
Also drop arm64e test-case for now.

Add missing #include

A forward declaration was insufficient here - since Regex needs to be
complete for the implicit dtor to be compiled correctly. (that, or the
dtor would have to be made explicit and out of line)

[SimplifyCFG] Fix inconsistency in block size assessment for threading

Sometimes SimplifyCFG may decide to perform jump threading. In order
to do it, it follows the following algorithm:

1. Checks if the block is small enough for threading;
2. If yes, inserts a PR Phi relying that the next iteration will remove it
   by performing jump threading;
3. The next iteration checks the block again and performs the threading.

This logic has a corner case: inserting the PR Phi increases block's size
by 1. If the block size at first check was max possible, one more Phi will
exceed this size, and we will neither perform threading nor remove the
created Phi node. As result, we will end up with worse IR than before.

This patch fixes this situation by excluding Phis from block size computation.
Excluding Phis from size computation for threading also makes sense by
itself because in case of threadign all those Phis will be removed.

Differential Revision: https://reviews.llvm.org/D81835
Reviewed By: asbirlea, nikic

Add front/back accessors to indexed_accessor_range.

These map to the similar accessors on ArrayRef and other random access containers.

This fixes a compilation error on MLIR ODS for variadic operands/results, which relied on the availability of front in certain situations.

[SVE][CodeGen] Fix bug in DAGCombiner::reduceBuildVecToShuffle

When trying to reduce a BUILD_VECTOR to a SHUFFLE_VECTOR it's
important that we carefully check the vector types that led to
that BUILD_VECTOR. In the test I have attached to this commit
there is a case where the results of two SVE faddv instructions
are being stored to consecutive memory locations. With my fix,
as part of merging those stores we discover that each BUILD_VECTOR
element came from an extract of a SVE vector element and
therefore bail out.

Differential Revision: https://reviews.llvm.org/D82564

[llvm-objcopy][MachO] Fix segment size alignment

This diff addresses the old TODO in MachOObjcopy.cpp and
correctly sets the page size used for alignment of segments.
In particular, now llvm-objcopy's output is consistent
with the input (the alignment of vmsize doesn't change).

Test plan:

1. make check-all
2. verify that a binary copied via llvm-objcopy now correctly works on iOS.

Differential revision: https://reviews.llvm.org/D82503

[SystemZ] Improve handling of ZERO_EXTEND_VECTOR_INREG.

Instead of doing multiple unpacks when zero extending vectors (e.g. v2i16 ->
v2i64), benchmarks have shown that it is better to do a VPERM (vector
permute) since that is only one sequential instruction on the critical path.

This patch achieves this by

1. Expand ZERO_EXTEND_VECTOR_INREG into a vector shuffle with a zero vector
   instead of (multiple) unpacks.

2. Improve SystemZ::GeneralShuffle to perform a single unpack as the last
   operation if Bytes matches it.

Review: Ulrich Weigand
Differential Revision: https://reviews.llvm.org/D78486

[CodeGen] Fix warning in getNode for EXTRACT_SUBVECTOR

Fix a warning in getNode() when extracting a subvector from a
concat vector. We can simply replace the call to getVectorNumElements
with getVectorMinNumElements as this follows the defined behaviour
for EXTRACT_SUBVECTOR.

Differential Revision: https://reviews.llvm.org/D82746

[X86] Remove an isel pattern than can never match. Remove bitcasts of loads from a few others.

Fix missing build dependency on omp_gen.

Summary:
`include/llvm/Frontend/OpenMP/CMakeLists.txt` creates a new target
called `omp_gen`, which is automatically added to
`LLVM_COMMON_DEPENDS` by the `add_public_tablegen_target` macro. But
it only gets added to the version of `LLVM_COMMON_DEPENDS` in the
scope of that subsidiary CMakeLists file, and it doesn't propagate all
the way back up to the permanent version of that variable which is
actually used to set dependencies.

The visible effect is that the output build scripts contain a missing
dependency. For example, if I run cmake in Ninja output mode, and then
run

  ninja -t commands tools/clang/examples/PrintFunctionNames/CMakeFiles/PrintFunctionNames.dir/PrintFunctionNames.cpp.o

to list all the commands that are prerequisites of building that
object file, then the list does not include the llvm-tblgen command
that builds `include/llvm/Frontend/OpenMP/OMP.h.inc`, even though that
generated include file is needed (by a chain of includes starting from
`clang/AST/AST.h`), and that object file can't be compiled without it.
This missing dependency can cause intermittent build failures,
depending on the order that Ninja (or whatever) happens to schedule
its commands.

I've fixed it by adding a `set` command in two levels of
`CMakeLists.txt` to propagate the modified version of
`LLVM_COMMON_DEPENDS` back up through the parent scopes so that
`omp_gen` does end up on the version seen by the main
`llvm/CMakeLists.txt`.

Reviewers: clementval, thakis, chandlerc, jdoerfert

Reviewed By: clementval

Subscribers: jdenny, mgorny, sstefan1, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82659

[Alignment][NFC] Migrate AArch64, ARM, Hexagon, MSP and NVPTX backends to Align

This patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Differential Revision: https://reviews.llvm.org/D82749

[MSP430] Declare comparison LibCalls as returning i16 instead of i32

For TI's distribution of msp430-gcc
```
msp430-elf-gcc -S -o- -Os -x c - <<< "int f(float a, float b) { return a != b; }"
```
does not mention `R13` at all. `__libgcc_cmp_return__` machine mode is 2 byte on MSP430, as well.

Differential Revision: https://reviews.llvm.org/D82635

[builtins] Change si_int to int in some helper declarations

This patch changes types of some integer function arguments or return values from `si_int` to the default `int` type to make it more compatible with `libgcc`.

The compiler-rt/lib/builtins/README.txt has a link to the [libgcc specification](http://gcc.gnu.org/onlinedocs/gccint/Libgcc.html#Libgcc). This specification has an explicit note on `int`, `float` and other such types being just illustrations in some cases while the actual types are expressed with machine modes.

Such usage of always-32-bit-wide integer type may lead to issues on 16-bit platforms such as MSP430. Provided [libgcc2.h](https://gcc.gnu.org/git/?p=gcc.git;a=blob_plain;f=libgcc/libgcc2.h;hb=HEAD) can be used as a reference for all targets supported by the libgcc, this patch fixes some existing differences in helper declarations.

This patch is expected to not change behavior at all for targets with 32-bit `int` type.

Differential Revision: https://reviews.llvm.org/D81285

[Alignment][NFC] Migrate PPC, X86 and XCore backends to Align

This patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Differential Revision: https://reviews.llvm.org/D82779

[Alignment][NFC] TargetLowering::allowsMemoryAccess

Second patch of a series to adapt TargetLowering::allowsXXX functions

This patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Differential Revision: https://reviews.llvm.org/D82785

[clang-tidy][docs] Fix malformed link in ReleaseNotes

[DWARFYAML][debug_info] Replace 'InitialLength' with 'Format' and 'Length'.

'InitialLength' is replaced with 'Format' (DWARF32 by default) and 'Length' in this patch.
Besides, test cases for DWARFv4 and DWARFv5, DWARF32 and DWARF64 is
added.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D82622

[MLIR][Shape] Fix lowering of `shape.get_extent`

The declarative conversion patterns caused crashes in the asan configuration.
The non-declarative implementation circumvents this.

Differential Revision: https://reviews.llvm.org/D82797

Revert "Fix missing build dependency on omp_gen."

This reverts commit ed4328c607306a2aa6df4833a0dce4482edbc94c.

My change apparently caused a buildbot to fail with the error

  CMake Error at /b/sanitizer-x86_64-linux-autoconf/build/tsan_release_build/lib/cmake/llvm/AddLLVM.cmake:869 (add_dependencies):
  The dependency target "omp_gen" of target "ScudoBenchmarks.x86_64" does not
  exist.

I don't at all understand why, because as far as I can see, the target
`omp_gen` is only added to `LLVM_COMMON_DEPENDS` after having been
created, so there //should// be no way it can end up on anything's
dependency list if it doesn't exist! But apparently it happened anyway.

Differential Revision: https://reviews.llvm.org/D82659

[mlir] Fix case in MLIRGPUtoVulkanTransforms

This changes the casing of MLIRGPUtoVulkanTransforms to be consistent
with other transform libraries.

Differential Revision: https://reviews.llvm.org/D82840

[GlobalISel][InlineAsm] Add support for matching input constraints

Find def operand that corresponds to matching constraint and
tie input to that operand.

Differential Revision: https://reviews.llvm.org/D82651

AMDGPU/GlobalISel: Select icmp intrinsic

Select into corresponding V_CMP instruction based on CmpInst predicate,
stored as immediate, in last operand.

Differential Revision: https://reviews.llvm.org/D82652

[yaml2obj] - Add a way to set default values for macros used in a YAML.

Currently we have to override all macros that are declared. But in many
cases it is convenient to use default values and to override only
a particular one or two.

This provides a way to set a default value for any macro:

```
Symbols:
  - Name: [[FOO=foo]]
```

Differential revision: https://reviews.llvm.org/D82455

[yaml2obj] - Support reading a content as an array of bytes using the new 'ContentArray' key.

It implements the way to describe a section content using a multi line description. E.g:

```
- Name:         .foo
  Type:         SHT_PROGBITS
  ContentArray: [ 0x11, 0x22, 0x33, 0x44,                                ## .long 11223344
                  0x55, 0x66,                                            ## .short 5566.
                  0x77,                                                  ## .byte 0x77
                  0x88, 0x99, 0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF, 0x00 ] ## .quad 0x8899aabbccddeeff
```

It was briefly discussed in D75123 thread previously.

Differential revision: https://reviews.llvm.org/D82366

[IR] NoFree IntrinsicProperty.

Summary:
Separate introduction of IntrNoFree property as suggested in D70365

Reviewers: arsenm, nhaehnle

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82587

[lldb] Modernize TestOperatorOverload.py asserts

[Alignment][NFC] Migrate AtomicExpandPass to Align

This is a followup on D78403.
I'm unsure about `getAtomicOpAlign` overloads that take `AtomicRMWInst` and `AtomicCmpXchgInst`, shouldn't `getAlign` provide the correct answer already?

Differential Revision: https://reviews.llvm.org/D81369

[AST][RecoveryExpr] Add error-bit to NestNameSpecifierDependence and TemplateNameDependence.

Summary:
We might lose the error-bit if the error-bit goes through the code path
"error type/expr" -> "error template argument" -> "nested name specifier" ->
... -> "template Specialization type"

Template name also needs this, as a template can be nested into
an error specifier, e.g. templateName apply in
`TC<decltype(<recovery-expr>(Foo, int()))>::template apply`

Reviewers: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D82526

[mlir] Extended BufferPlacement to support nested region control flow.

Summary: The current BufferPlacement implementation does not support
nested region control flow. This CL adds support for nested regions via
the RegionBranchOpInterface and the detection of branch-like
(ReturnLike) terminators inside nested regions.

Differential Revision: https://reviews.llvm.org/D81926

[clangd] Remove redundant `findRefs` calls. NFC.

Summary:
Remove redundant `findRefs` calls.

Reviewers: sammccall, kadircet

Subscribers: ilya-biryukov, MaskRay, jkorous, arphaman, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D82714

[llvm][Z3][NFC] Improve mkBitvector performance

We convert `APSInt`s to Z3 Bitvectors in an inefficient way for most cases.
We should not serialize to std::string just to pass an int64 integer.

For the vast majority of cases, we use at most 64-bit width integers (at least
in the Clang Static Analyzer). We should simply call the `Z3_mk_unsigned_int64`
and `Z3_mk_int64` instead of the `Z3_mk_numeral` as stated in the Z3 docs.
Which says:
> It (`Z3_mk_unsigned_int64`, etc.) is slightly faster than `Z3_mk_numeral` since
> it is not necessary to parse a string.

If the `APSInt` is wider than 64 bits, we will use the `Z3_mk_numeral` with a
`SmallString` instead of a heap-allocated `std::string`.

Differential Revision: https://reviews.llvm.org/D78453

[SystemZ] Add NoMerge MIFlag

Summary:
This fixes ASan and MSan tests on SystemZ after
commit 6a822e20ce70 ("[ASan][MSan] Remove EmptyAsm and set the CallInst
to nomerge to avoid from merging.").

Based on commit 80e107ccd088 ("Add NoMerge MIFlag to avoid MIR branch
folding").

Reviewers: uweigand, jonpa

Reviewed By: uweigand

Subscribers: hiraditya, llvm-commits, Andreas-Krebbel

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82794

[lldb][NFC] Remove ImportInProgress lock in ClangASTSource

Summary:

The ClangASTSource has a lock that globally disables all lookups into the
external AST source when we explicitly "guarded" copy a type. It's not used for
anything else, so importing declarations or importing types that are
dependencies of a declaration actually won't activate that lock. The lookups it
is supposed to prevent also don't actually happen in our test suite. The check
in `ClangExpressionDeclMap::FindExternalVisibleDecls` is never executed and the
check in the `ClangASTSource::FindExternalVisibleDeclsByName` is only ever
reached by the `Import-std-module` tests (which explicitly do a lookup into the
expression context on purpose).

This lock was added in 6abfabff6158076eccdf6fcac5a12894039de2c9 as a replacement
for a list of types we already looked up which appeared to be an optimisation
strategy. I assume back then this lock had a purpose but these days the
ASTImporter and LLDB seem to be smart enough to avoid whatever lookups this
tried to prevent.

I would say we remove it from LLDB. The main reason is that it blocks D81561
(which explicitly does a specific lookup to resolve placeholder types produced
by `-flimit-debug-info`) but it's semantics are also very confusing. The naming
implies it's a flag to indicate when we import something at the moment which is
practically never true as described above. Also the fact that it makes our
ExternalASTSource alternate between doing lookups into the debug info and
pretending it doesn't know any external decls could really break our lookup in
some weird way if Clang decides to cache a fake empty lookup result that was
generated while the lock was active.

Reviewers: labath, shafik, JDevlieghere, aprantl

Reviewed By: labath, JDevlieghere, aprantl

Subscribers: aprantl, abidh

Differential Revision: https://reviews.llvm.org/D81749

[lldb] Tab completion for `frame select`

Summary: Provided the tab completion for command `frame select`.

Reviewers: teemperor, JDevlieghere

Reviewed By: teemperor

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D81177