Previously we don't catch the reachability for partial specialization.
Handle them in this patch.

Copying the folder keeps the original permissions by default. This
creates problems when the source folder is read-only, e.g. in a
packaging environment.
Then, the copied folder in the build directory is read-only as well.
Later on, with configure_file, ClangConfig.cmake is copied into that
directory (in the build tree), failing when the directory is read-only.

Fix that problem by copying the folder without keeping the original
permissions.

Differential Revision: https://reviews.llvm.org/D130254

These can be used to quantify parsing improvements from a change.

Differential Revision: https://reviews.llvm.org/D130199

MarkupFilter keeps a reference to the last filtered StringRef. Just keep
it alive a bit longer. Found by asan.

And avoid redundant identify_magic test.

Reviewed By: paulwalker-arm

Differential Revision: https://reviews.llvm.org/D130093

Reviewed By: paulwalker-arm

Differential Revision: https://reviews.llvm.org/D130094

Also test realloc, and dead writes to the allocation.

The re-land fixes module map module dependencies seen on Greendragon, but
not in the clang test suite.

---

Currently we only implement this for the Itanium ABI since the correct
mangling for the initializers in other ABIs is not yet known.

Intended result:

For a module interface [which includes partition interface and implementation
units] (instead of the generic CXX initializer) we emit a module init that:

 - wraps the contained initializations in a control variable to ensure that
   the inits only happen once, even if a module is imported many times by
   imports of the main unit.

 - calls module initializers for imported modules first.  Note that the
   order of module import is not significant, and therefore neither is the
   order of imported module initializers.

 - We then call initializers for the Global Module Fragment (if present)
 - We then call initializers for the current module.
 - We then call initializers for the Private Module Fragment (if present)

For a module implementation unit, or a non-module TU that imports at least one
module we emit a regular CXX init that:

 - Calls the initializers for any imported modules first.
 - Then proceeds as normal with remaining inits.

For all module unit kinds we include a global constructor entry, this allows
for the (in most cases unusual) possibility that a module object could be
included in a final binary without a specific call to its initializer.

Implementation:

 - We provide the module pointer in the AST Context so that CodeGen can act
   on it and its sub-modules.

 - We need to account for module build lines like this:
  ` clang -cc1 -std=c++20 Foo.pcm -emit-obj -o Foo.o` or
  ` clang -cc1 -std=c++20 -xc++-module Foo.cpp -emit-obj -o Foo.o`

 - in order to do this, we add to ParseAST to set the module pointer in
   the ASTContext, once we establish that this is a module build and we
   know the module pointer. To be able to do this, we make the query for
   current module public in Sema.

 - In CodeGen, we determine if the current build requires a CXX20-style module
   init and, if so, we defer any module initializers during the "Eagerly
   Emitted" phase.

 - We then walk the module initializers at the end of the TU but before
   emitting deferred inits (which adds any hidden and static ones, fixing
   https://github.com/llvm/llvm-project/issues/51873 ).

 - We then proceed to emit the deferred inits and continue to emit the CXX
   init function.

Differential Revision: https://reviews.llvm.org/D126189

- the grammar ambiguity is eliminated by a guard;
- modify the guard function signatures, now all parameters are folded in
  to a single object, avoid a long parameter list (as we will add more
  parameters in the near future);

Reviewed By: sammccall

Differential Revision: https://reviews.llvm.org/D130160

This patch adds support for evaluating expressions which reference
a captured `this` from within the context of a C++ lambda expression.
Currently LLDB doesn't provide Clang with enough information to
determine that we're inside a lambda expression and are allowed to
access variables on a captured `this`; instead Clang simply fails
to parse the expression.

There are two problems to solve here:
1. Make sure `clang::Sema` doesn't reject the expression due to an
illegal member access.
2. Materialize all the captured variables/member variables required
to evaluate the expression.

To address (1), we currently import the outer structure's AST context
onto `$__lldb_class`, making the `contextClass` and the `NamingClass`
match, a requirement by `clang::Sema::BuildPossibleImplicitMemberExpr`.

To address (2), we inject all captured variables as locals into the
expression source code.

**Testing**

* Added API test

This is required in preparation for the follow-up patch which adds
support for evaluating expressions from within C++ lambdas. In such
cases we need to materialize variables which are not part of the
current frame but instead are ivars on a 'this' pointer of the current
frame.

Lower F08 maskl and maskr intrinsics.

Differential Revision: https://reviews.llvm.org/D129296

Lower F08 shift (shiftl, shiftr, shifta) and combined shift (dshiftl, dshiftr)
intrinsics. The combined shift intrinsics are implemented using the
definitions of shiftl and shiftr as described by the standard.

For non-conformant arguments to the shift intrinsics, the implementation tries
to replicate the behavior of other compilers if most of the other behave
consistently.

Differential Revision: https://reviews.llvm.org/D129316

Test compile-time folding of F08 maskl and maskr intrinsics.

Differential Revision: https://reviews.llvm.org/D129663

Test compile-time folding of F08 shift (shiftl, shiftr, shifta) and combined shift (dshiftl, dshiftr) intrinsics.

Differential Revision: https://reviews.llvm.org/D129696

Lower F08 bit population count intrinsics popcnt, poppar, leadz and trailz. popcnt, leadz and trailz are implemented using the corresponding MLIR math intrinsics. poppar is implemented in terms of popcnt.

Differential Revision: https://reviews.llvm.org/D129584

If a function is non-recursive we only performed intra-procedural
reasoning for reachability (via AA::isPotentiallyReachable). However,
if it is re-entrant that doesn't mean we can't reach. Instead of this
problematic logic in the reachability reasoning we utilize logic in
AAPointerInfo. If a location is for sure written by a function it can
be re-entrant or recursive we know only intra-procedural reasoning is
sufficient.

The existing code doesn't expect dummy values (undef, poison, null-derived
constants etc) as arguments of these intrinsics. However, they can be there
in unreached code. Currently we fail trying to find base for them.

Handle these cases separately. Return null as base for them to be consistent
with the handling in the main algorithm in findBaseDefiningValue.

Differential Revision: https://reviews.llvm.org/D129561
Reviewed By: apilipenko

Add affine.if canonicalization to compose affine.apply ops into its set
and operands. This eliminates affine.apply ops feeding into affine.if
ops.

Differential Revision: https://reviews.llvm.org/D130242

If we have a dominating must-write access we do not need to know the
initial value of some object to perform reasoning about the potential
values. The dominating must-write has overwritten the initial value.

These were forgotten when D118680 was applied. Similar to D125937.

Differential Revision: https://reviews.llvm.org/D129516

This reverts commit 51d3f421.

This reverts commit 9dc0d6aa.

The namespaces were missing causing the symbols to have "C" mangling.
To avoid this in the future we qualify the names now fully.

lowerGlobalAddress added by D128427 can be used for PIC. The actual condition is
that the global value needs to be dso_local (a dso_preemptable one needs GOT
indirection).

load-store.ll has UB due to out-of-bounds load/store. Fix the UB in the variable
test and add an array test. Note: NOPIC array index is currently wrong.

Reviewed By: wangleiat

Differential Revision: https://reviews.llvm.org/D129977

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D130220

Diagnostic for `-Wauto-import` shouldn't be a warning because it doesn't
represent a potential problem in code that should be fixed. And the
emitted fix-it is likely to trigger `-Watimport-in-framework-header`
which makes it challenging to have a warning-free codebase. But it is
still useful to see how include directives are translated into modular
imports and which module a header belongs to, that's why keep it as a remark.

Keep `-Wauto-import` for now to allow a gradual migration for codebases
using `-Wno-auto-import`, e.g., `-Weverything -Wno-auto-import`.

rdar://79594287

Differential Revision: https://reviews.llvm.org/D130138