Changes

[NFC] Suppress "warning: ignoring return value"

[NFC][libc++] Suppress "warning: ignoring return value"

According to the comment on the next line
it's expected behaviour.

[sanitizers][NFC] Change typesto avoid warnings

Warning was enabled by D94640

[dfsan] Record dfsan metadata in globals

This will allow identifying exactly how many shadow bytes were used
during compilation, for when fast8 mode is introduced.

Also, it will provide a consistent matching point for instrumentation
tests so that the exact llvm type used (i8 or i16) for the shadow can
be replaced by a pattern substitution. This is handy for tests with
multiple prefixes.

Reviewed by: stephan.yichao.zhao, morehouse

Differential Revision: https://reviews.llvm.org/D97409

[flang] Detect circularly defined interfaces of procedures

It's possible to define a procedure whose interface depends on a procedure
which has an interface that depends on the original procedure.  Such a circular
definition was causing the compiler to fall into an infinite loop when
resolving the name of the second procedure.  It's also possible to create
circular dependency chains of more than two procedures.

I fixed this by adding the function HasCycle() to the class DeclarationVisitor
and calling it from DeclareProcEntity() to detect procedures with such
circularly defined interfaces.  I marked the associated symbols of such
procedures by calling SetError() on them.  When processing subsequent
procedures, I called HasError() before attempting to analyze their interfaces.
Unfortunately, this did not work.

With help from Tim, we determined that the SymbolSet used to track the
erroneous symbols was instantiated using a "<" operator which was
defined using the name of the procedure.  But the procedure name was
being changed by a call to ReplaceName() between the times that the
calls to SetError() and HasError() were made.  This caused HasError() to
incorrectly report that a symbol was not in the set of erroneous
symbols.  I fixed this by making SymbolSet be an ordered set, which does
not use the "<" operator.

I also added tests that will crash the compiler without this change.
And I fixed the formatting on an error message from a previous update.

Differential Revision: https://reviews.llvm.org/D97201

[DAGCombiner] Optimize SMULO/UMULO if we can prove that overflow is impossible.

Using ComputeNumSignBits or computeKnownBits we might be able
to determine that overflow is impossible.

This especially helps after type legalization if the type was
promoted from a type with half the bits or more. Type legalization
conservatively creates a promoted smulo/umulo and an overflow
check for the promoted bits. The overflow from the promoted
smulo/umulo is ORed with the result of the promoted bits
overflow check. Proving that the promoted smulo/umulo can never
overflow will leave us with just the promoted bits overflow check.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D97160

AMDGPU: Use kill instruction to hint soft clause live ranges

Previously we would use a bundle to hint the register allocator to not
overwrite the pointers in a sequence of loads to avoid breaking soft
clauses. This bundling was based on a fuzzy register pressure
heuristic, so we could not guarantee using more registers than are
really available. This would result in register allocator failing on
unsatisfiable bundles. Use a kill to artificially extend the live
ranges, so we can always succeed at register allocation even if it
means extra spills in the worst case.

This seems to capture most of the benefit of the bundle while avoiding
most of the risk presented by the bundle. However the lit tests do
show a handful of regressions. In some cases with sequences of
volatile loads, unused load components end up getting reallocated to
the next load which forces a wait between. There are also a few small
scheduling regressions where a hazard used to be avoided, and one
spill torture test which for some reason nearly doubles the stack
usage. There is also a bit of noise from leftover kills (it may make
sense for post-RA pseudos to strip all of these out).

[docs] Add documentation on using the new pass manager

And clarify in the "writing a pass" docs that both the legacy and new
PMs are being used for the codegen/optimization pipelines.

Reviewed By: ychen, asbirlea

Differential Revision: https://reviews.llvm.org/D97515

[MLIR][TOSA] Lower tosa.identity and tosa.identitiyn to linalg

Both identity ops can be loweried by replacing their results with their
inputs. We keep this as a linalg lowering as other backends may choose to
create copies.

Differential Revision: https://reviews.llvm.org/D97517

[clang] implicitly delete space ship operator with function pointers

See bug #48856

Definitions of classes with member function pointers and default
spaceship operator were getting accepted with no diagnostic on
release build, and triggering assert on builds with runtime checks
enabled. Diagnostics were only produced when actually comparing
instances of such classes.

This patch makes it so Spaceship and Less operators are not considered
as builtin operator candidates for function pointers, producing
equivalent diagnostics for the cases where pointers to member function
and pointers to data members are used instead.

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D95409

[flang][fir][NFC] Removes deprecated messages in builds.

[InstrProfiling] Use llvm.compiler.used instead of llvm.used for ELF

Many optimizers (e.g.  GlobalOpt/ConstantMerge) do not respect linker semantics
for comdat and may not discard the sections as a unit.

The interconnected `__llvm_prf_{cnts,data}` sections (in comdat for ELF)
are similar to D97432: `__profd_` is not directly referenced, so
`__profd_` may be discarded while `__profc_` is retained, breaking the
interconnection.  We currently conservatively add all such sections to
`llvm.used` and let the linker do GC for ELF.

In D97448, we will change GlobalObject's in the llvm.used list to use SHF_GNU_RETAIN,
causing the metadata sections to be unnecessarily retained (some `check-profile` tests check for GC).
Use `llvm.compiler.used` to retain the current GC behavior.

Differential Revision: https://reviews.llvm.org/D97585

[Driver] Print process statistics report on CC_PRINT_PROC_STAT env variable.

Added supporting CC_PRINT_PROC_STAT and CC_PRINT_PROC_STAT_FILE
environment variables to trigger clang driver reporting the process
statistics into specified file (alternate for -fproc-stat-report
option).

Differential Revision: https://reviews.llvm.org/D97094

Reland "[builtins] Define fmax and scalbn inline"

This reverts commit 680f836c2fa72166badd594a52b3f41b2ad074d2.

Disable the non-default-rounding-mode scalbn[f] tests when we're using
the MSVC libraries.

Differential Revision: https://reviews.llvm.org/D91841

[mlir] Add regions to OpAdaptor

Allows querying regions too via OpAdaptor's generated. This does not yet move region verification to adaptor nor require regions for ops where needed.

Differential Revision: https://reviews.llvm.org/D97519

[test] Fix PGOProfile/comdat_internal.ll

[AArch64][GlobalISel] Import FMOV patterns rather than manually selecting it

There are existing patterns for FMOVHi, FMOVSi, and FMOVDi in
AArch64InstrFormats.td.

Importing these allows us to remove the manual selection code for FMOV.

It also allows us to select FMOVHi for non-zero constants when we have full
fp-16 support.

Refactor some of the code in AArch64InstrFormats.td so that we can create
equivalent custom renderers in GlobalISel.

Differential Revision: https://reviews.llvm.org/D97511

[msan] Use non-transparent-huge-page at SetShadow

This prevents from getting THP ranges more and more.

Did not see any issues in practice, just found this by code review.

Reviewed By: eugenis, vitalybuka

Differential Revision: https://reviews.llvm.org/D97593

[Driver] Fix a warning about the the initialization order

Add GNU attribute 'retain'

For ELF targets, GCC 11 will set SHF_GNU_RETAIN on the section of a
`__attribute__((retain))` function/variable to prevent linker garbage
collection. (See AttrDocs.td for the linker support).

This patch adds `retain` functions/variables to the `llvm.used` list, which has
the desired linker GC semantics. Note: `retain` does not imply `used`,
so an unused function/variable can be dropped by Sema.

Before 'retain' was introduced, previous ELF solutions require inline asm or
linker tricks, e.g.  `asm volatile(".reloc 0, R_X86_64_NONE, target");`
(architecture dependent) or define a non-local symbol in the section and use
`ld -u`. There was no elegant source-level solution.

With D97448, `__attribute__((retain))` will set `SHF_GNU_RETAIN` on ELF targets.

Differential Revision: https://reviews.llvm.org/D97447

ELF: Create unique SHF_GNU_RETAIN sections for llvm.used global objects

If a global object is listed in `@llvm.used`, place it in a unique section with
the `SHF_GNU_RETAIN` flag. The section is a GC root under `ld --gc-sections`
with LLD>=13 or GNU ld>=2.36.

For front ends which do not expect to see multiple sections of the same name,
consider emitting `@llvm.compiler.used` instead of `@llvm.used`.

SHF_GNU_RETAIN is restricted to ELFOSABI_GNU and ELFOSABI_FREEBSD in
binutils. We don't do the restriction - see the rationale in D95749.

The integrated assembler has supported SHF_GNU_RETAIN since D95730.
GNU as>=2.36 supports section flag 'R'.
We don't need to worry about GNU ld support because older GNU ld just ignores
the unknown SHF_GNU_RETAIN.

With this change, `__attribute__((retain))` functions/variables emitted
by clang will get the SHF_GNU_RETAIN flag.

Differential Revision: https://reviews.llvm.org/D97448

[Polly] Refactoring IsInnermostParallel() in ISL to take the C++ wrapper object. NFC

Currently, the IslAst library is a C library that would be incompatible with the rest of the LLVM because LLVM is written in C++.
I took one function, IsInnermostParallel(), and refactored it so that it would take the C++ wrapper object instead of using reference counters with the C ISL library. As well, all the references that use IsInnermostParallel() will use manage_copy() since they are still expecting the C object.

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D97425

[lld][WebAssembly] Rename methods/members to match ELF backend. NFC.

Specifically:

- InputChunk::outputOffset -> outSecOffset
- Symbol::get/setVirtualAddress -> get/setVA
- add InputChunk::getOffset helper that takes an offset

These are mostly in preparation for adding support for
SHF_MERGE/SHF_STRINGS but its also good to align with ELF where
possible.

Differential Revision: https://reviews.llvm.org/D97595

[WebAssembly] Fix reverse mapping in WasmEHFuncInfo

D97247 added the reverse mapping from unwind destination to their
source, but it had a critical bug; sources can be multiple, because
multiple BBs can have a single BB as their unwind destination.

This changes `WasmEHFuncInfo::getUnwindSrc` to `getUnwindSrcs` and makes
it return a vector rather than a single BB. It does not return the const
reference to the existing vector but creates a new vector because
`WasmEHFuncInfo` stores not `BasicBlock*` or `MachineBasicBlock*` but
`PointerUnion` of them. Also I hoped to unify those methods for
`BasicBlock` and `MachineBasicBlock` into one using templates to reduce
duplication, but failed because various usages require `BasicBlock*` to
be `const` but it's hard to make it `const` for `MachineBasicBlock`
usages.

Fixes https://github.com/emscripten-core/emscripten/issues/13514.
(More precisely, fixes
https://github.com/emscripten-core/emscripten/issues/13514#issuecomment-784708744)

Reviewed By: dschuff, tlively

Differential Revision: https://reviews.llvm.org/D97583

[flang][fir] Add remaining Ops. Updates to pre-existing Ops.

  - add ops: rebox, insert_on_range, absent, is_present
  - embox, coordinate_of: replace old hand-written parser/pretty-printer with assembly format
  - remove dead floating point ops, since buitlins work for all types
  - update call op
  - update documentation
  - misc. NFC to formatting
  - add op round trip tests

Authors: Eric Schweitz, Jean Perier, Zachary Selk, Kiran Chandramohan, et.al.

Differential Revision: https://reviews.llvm.org/D97500