Changes

[LoopUnroll] Support loops with exiting block that is neither header nor
latch.

Summary: Remove the limitation in LoopUnrollPass that exiting block must
be either header or latch.
Reviewer: dmgreen, jdoerfert, Meinersbur, kbarton, bmahjour, etiotto,
fhahn, efriedma
Reviewed By: etiotto, fhahn, efriedma
Subscribers: efriedma, lkail, xbolva00, hiraditya, zzheng, llvm-commits
Tag: LLVM
Differential Revision: https://reviews.llvm.org/D80477

[llvm-xray][test] Fix unsupported-elf32.txt after D80185

[WebAssembly] Fix a bug in removing unnecessary branches

Summary:
One of the things `removeUnnecessaryInstrs()` in CFGStackify does is to
remove an unnecessary unconditinal branch before an EH pad. When there
is an unconditional branch right before a catch instruction and it
branches to the end of `end_try` marker, we don't need the branch,
because it there is no exception, the control flow transfers to
that point anyway.
```
bb0:
  try
    ...
    br bb2      <- Not necessary
bb1:
  catch
    ...
bb2:
  end
```

This applies when we have a conditional branch followed by an
unconditional one, in which case we should only remove the unconditional
branch. For example:
```
bb0:
  try
    ...
    br_if someplace_else
    br bb2                 <- Not necessary
bb1:
  catch
    ...
bb2:
  end
```

But `TargetInstrInfo::removeBranch` we used removed all existing
branches when there are multiple ones. This patch fixes it by only
deleting the last (= unconditional) branch manually.

Also fixes some `preds` comments in the test file.

Reviewers: dschuff

Subscribers: sbc100, jgravelle-google, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80572

[WebAssembly] Fix a bug in finding matching EH pad

Summary:
`getMatchingEHPad()` in LateEHPrepare is a function to find the nearest
EH pad that dominates the given instruction. This intends to be
lightweight so it does not use full WebAssemblyException scope analysis
or dominator analysis. It simply does backward BFS to its predecessors
and stops at the first EH pad each search path encounters. All search
should end up at the same EH pad, and if not, it returns null.

But it didn't take into account that when there are inner scopes within
the current scope, some path in BFS can hit an inner EH pad first. For
example, in the given diagram, `Inst` belongs to the outer scope and
`getMathingEHPad()` should return 'EHPad 1', but some search path can go
into the inner scope and end up with 'EHPad 2'. The search will return
null because different paths end up with different EH pads.
```
--- EHPad 1 ---
| - EHPad 2 - |
| |         | |
| ----------- |
|   Inst      |
---------------
```

So far this was OK because we haven't tested a case in which a given
instruction is far from its EH pad. Also, this bug does not happen when
the inner EH scope is a cleanup scope, because a cleanup scope ends with
a `cleanupret` whose successor is an EH pad, so the search encounters
that EH pad first before going into the child scope. But this can happen
when the child scope is a catch scope that ends with `catchret`. So this
patch, when doing backward BFS, does not search predecessors that ends
with `catchret`. Because `catchret`s are replaced with `br`s during this
pass, this records BBs that have `catchret`s in the beginning, before
doing any other transformations.

Reviewers: dschuff

Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80571

[ObjectYAML][DWARF] Add DWARF entry in ELFYAML.

This patch adds a new DWARF entry in ELF YAML file.

Reviewed By: grimar

Differential Revision: https://reviews.llvm.org/D80203

[Tests] Migrate more statepoint lowering tests to use operand bundles

Only 2 tests left after this.  They just happen to be the most annoying.

[LoopUnroll] Fix not-rotated.ll by adding back a limitation was unintentionally
removed in https://reviews.llvm.org/D80477

[JITLink] Fix 80-column rule violation.

[JITLink] Improve llvm-jitlink regression testing support for ELF.

This patch adds a jitlink pass, 'registerELFGraphInfo', that records section
and symbol information about each LinkGraph in the llvm-jitlink session object.
This allows symbols and sections to be referred to by name in llvm-jitlink
regression tests. This will enable a testcase to be written for
https://reviews.llvm.org/D80613.

[ORC] Add debugging output for LLJIT construction.

This can be handy for checking whether the LLJIT instance you're constructing
matches your expectations.

[gn build] Port a6deaeec370

[AArch64][GlobalISel] Enable extending loads combines post-legalization.

During legalization we can end up with extends of loads, which in the case of
zexts causes us to not hit tablegen imported patterns.

The caveat here is that we don't want anyext load forming, since some variants
are illegal. This change also prevents the combine from creating any illegal
loads.

Differential Revision: https://reviews.llvm.org/D80458

[X86] Remove MMX isel patterns containing (x86mmx (scalar_to_vector (i32))).

I don't think we can make such a node. I don't think
x86_mmx is considered a vector for the check in getNode.

[libc] Add implementation of call_once from threads.h.

Reviewers: abrachet, maskray

Differential Revision: https://reviews.llvm.org/D79828

[CodeGen] Add support for extracting elements of scalable vectors

I have tried to ensure that SelectionDAG and DAGCombiner do
sensible things for scalable vectors, and added support for a
limited number of simple folds. Codegen support for the vector
extract patterns have also been added to the AArch64 backend.

New vector extract tests have been added here:

  CodeGen/AArch64/sve-extract-element.ll

and I have also added new folds using inserts and extracts here:

  CodeGen/AArch64/sve-insert-element.ll

Differential Revision: https://reviews.llvm.org/D80208

[SVE] Fix warnings in SelectInst::areInvalidOperands

We should be comparing the element counts rather than the
numbers of elements.

Differential Revision: https://reviews.llvm.org/D80634

[SVE] Remove getNumElements() warnings in InstCombiner::visitBitCast

Whilst trying to compile this test to assembly:

  CodeGen/aarch64-sve-intrinsics/acle_sve_reinterpret.c

I discovered some warnings were firing in InstCombiner::visitBitCast
due to calls to getNumElements() for scalable vector types. These
calls only really made sense for fixed width vectors so I have fixed
up the code appropriately.

Differential Revision: https://reviews.llvm.org/D80559

[CMake] Pass CLANG_VENDOR variables into later stages

We are already passing CLANG_VERSION_* & PACKAGE_VENDOR

libclc: update website url

old link is dead