Changes

AMDGPU: Fix clang side null pointer value for private

The change to fold_priv_arith looks strange to me, but this was
already the untested behavior for local.

[lldb] Handle a new clang built-in type

Remove a comment-out llvm::errs debugging code, NFC.

AMDGPU: Fix not using scalar loads for global reads in shaders

The pass which infers when it's legal to load a global address space
as SMRD was only considering amdgpu_kernel, and ignoring the shader
entry type calling conventions.

[AST][RecoveryExpr] Build RecoveryExpr for "undef_var" cases.

Summary:
For a none-function-like unresolved expression, clang builds a TypoExpr
for it, and tries to correct it afterwards. If the typo-correction
fails, clang just drops the whole expr.

This patch improves the recovery strategy -- if the typo-correction
fails, we preserve the AST by degrading the typo exprs to recovery
exprs.

This would improve toolings for "undef_var" broken cases:
```
void foo();
void test() {
  fo^o(undef_var); // go-to-def, hover still works.
}
```

TESTED=ran tests with this patch + turn-on-recovery-ast patch, it breaks
one declare_variant_messages testcase (the diagnostics are slightly
changed), I think it is acceptable.

```
Error: 'error' diagnostics seen but not expected:
  File llvm-project/clang/test/OpenMP/declare_variant_messages.cpp Line 16: expected 'match' clause on 'omp declare variant' directive
  File llvm-project/clang/test/OpenMP/declare_variant_messages.cpp Line 57: expected 'match' clause on 'omp declare variant' directive
error: 'warning' diagnostics expected but not seen:
  File llvm-project/clang/test/OpenMP/declare_variant_messages.cpp Line 47: the context selector 'kind' in the context set 'device' cannot have a score ('<invalid>'); score ignored
  File llvm-project/clang/test/OpenMP/declare_variant_messages.cpp Line 87: the context selector 'kind' in the context set 'device' cannot have a score ('<invalid>'); score ignored
error: 'warning' diagnostics seen but not expected:
  File llvm-project/clang/test/OpenMP/declare_variant_messages.cpp Line 47: the context selector 'kind' in the context set 'device' cannot have a score ('<recovery-expr>()'); score ignored
  File llvm-project/clang/test/OpenMP/declare_variant_messages.cpp Line 87: the context selector 'kind' in the context set 'device' cannot have a score ('<recovery-expr>()'); score ignored
6 errors generated.
```

Reviewers: sammccall, jdoerfert

Subscribers: sstefan1, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D80733

Use Pseudo Instruction to carry stack probing information

Instead of using a fake call and metadata to temporarily represent a probed
static alloca, use a pseudo instruction.

This is inspired by the SystemZ approach proposed in https://reviews.llvm.org/D78717.

Differential Revision: https://reviews.llvm.org/D80641

[yaml2obj] - Allocate the file space for SHT_NOBITS sections in some cases.

This teaches yaml2obj to allocate file space for a no-bits section
when there is a non-nobits section in the same segment that follows it.

It was discussed in D78005 thread and matches GNU linkers and LLD behavior.

Differential revision: https://reviews.llvm.org/D80629

Renamed Lang_C to Lang_C99, Lang_CXX to Lang_CXX03, and 2a to 20

Summary:
I think we would be better off with tests explicitly specifying the
language mode. Right now Lang_C means C99, but reads as "any C version",
or as "unspecified C version".

I also changed '-std=c++98' to '-std=c++03' because they are aliases (so
there is no difference in practice), because Clang implements C++03
rules in practice, and because 03 makes a nice sortable progression
between 03, 11, 14, 17, 20.

Reviewers: shafik, hlopko

Reviewed By: hlopko

Subscribers: jfb, martong, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D81000

[OPENMP50]Initial codegen for 'affinity' clauses.

Summary:
Added initial codegen for 'affinity' clauses on task directives.
Emits next code:
```
kmp_task_affinity_info_t affs[<num_elems>];

void *td = __kmpc_task_alloc(..);

affs[<i>].base = &data_i;
affs[<i>].size = sizeof(data_i);
__kmpc_omp_reg_task_with_affinity(&loc, <gtid>, td, <num_elems>, affs);
```

The result returned by the call of `__kmpc_omp_reg_task_with_affinity`
function is ignored currently sincethe  runtime currently ignores args
and returns 0 uncoditionally.

Reviewers: jdoerfert

Subscribers: yaxunl, guansong, sstefan1, llvm-commits, cfe-commits, caomhin

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D80240

Reinstate the syntax tree test for 'static' in an array subscript

Reviewers: eduucaldas

Reviewed By: eduucaldas

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D81009

[Dexter] Add os.path.normcase(...) transform to test path early.

  When passing a test path, if the path points directly at a file, then
  normcase would not be called on path.

  This would change the expected lower case drive path, on windows, to be
  uppercase. This patch simply calls normcase on the test path at the earliest
  point possible to avoid this issue.

  Reviewers: djtodoro, jmorse

  Differential Revision: https://reviews.llvm.org/D78633

[Dexter] Add DexLimitSteps command and ConditionalController

  * Adds DexLimitSteps Command.
  * Add ConditionalController, a new DebuggerController type.
  * 5 regression tests
  * documentation

  Reviewers: jmorse

  Differential Revision: https://reviews.llvm.org/D79786

[flang] Fix release build flags.

Summary:
This patch removes the custom CMAKE_RELEASE_CXX_FLAGS variable.
This variable being set was having the effect of removing other important
Release flags, notably `-DNDEBUG`.

This patch may need to be accompanied by fixes for the macOS issues that
the removed comment mentions; I don't have a mac to test this on though so
hopefully a reviewer can help with that.

Reviewers: Andrzej, tskeith, sscalpone

Subscribers: mgorny, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80794