Differential Revision: https://reviews.llvm.org/D97605

In the example based on:
https://llvm.org/PR49218
...we are crashing because poison is a subclass of undef, so we merge blocks and create:

PHI node has multiple entries for the same basic block with different incoming values!
  %k3 = phi i64 [ poison, %entry ], [ %k3, %g ], [ undef, %entry ]

If both poison and undef values are incoming, we soften the poison values to undef.

Differential Revision: https://reviews.llvm.org/D97495

Per the discussion in D97453. We currently disable it due to it's not a
common scenario and has some problem in implementation.

Differential Revision: https://reviews.llvm.org/D97453

Differential Revision: https://reviews.llvm.org/D97150

Differential Revision: https://reviews.llvm.org/D97153

Differential Revision: https://reviews.llvm.org/D97152

Differential Revision: https://reviews.llvm.org/D97151

Differential Revision: https://reviews.llvm.org/D97149

Differential Revision: https://reviews.llvm.org/D97147

Differential Revision: https://reviews.llvm.org/D97145

Differential Revision: https://reviews.llvm.org/D97144

Differential Revision: https://reviews.llvm.org/D96222

[llvm] Add assertions for the smart pointers with the possibility to be null in DWARFLinker::loadClangModule

Split from D91844.

The local variable `Unit` in function `DWARFLinker::loadClangModule`
in file `llvm/lib/DWARFLinker/DWARFLinker.cpp`. If the variable is not set
in the loop below its definition, it will trigger a null pointer dereference
after the loop.

Patch By: OikawaKirie

Reviewed By: avl

Differential Revision: https://reviews.llvm.org/D97185

This function will be used in subsequent upstreaming merges.

Author: Jean Perier

Differential Revision: https://reviews.llvm.org/D97502

This also exposed a bug in Dialect loading where it was not correctly identifying identifiers that had the dialect namespace as a prefix.

Differential Revision: https://reviews.llvm.org/D97431

Includes a lowering for tosa.const, tosa.if, and tosa.while to Standard/SCF dialects. TosaToStandard is
used for constant lowerings and TosaToSCF handles the if/while ops.

Resubmission of https://reviews.llvm.org/D97518 with ASAN fixes.

Differential Revision: https://reviews.llvm.org/D97529

This should now be about as style-conforming as TableGen'ed code ever
can reasonably be.

  - 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

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

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

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

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

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

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

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

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

This reverts commit 680f836c.

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

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

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

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

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

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

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