Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
10.0.0 release.

MFC r356479 (by bdragon):

[PowerPC] Fix libllvmminimal build when building from powerpc64 ELFv1.

When bootstrapping on powerpc64 ELFv1, it is necessary to use binutils
ld.bfd from ports for the bootstrap, as this is the only modern linker for
ELFv1 host tools.

As binutils ld.bfd is rather strict in its handling of undefined symbols,
it is necessary to pull in Support/Atomic.cpp to avoid an undefined symbol.

Reviewed by:	dim, emaste
Sponsored by:	Tag1 Consulting, Inc.
Differential Revision:	https://reviews.freebsd.org/D23072

MFC r356930:

Add more Subversion mergeinfo bootstrap information, to hopefully
increase the probability of merging in vendor changes.

MFC r358408 (by brooks):

Merge commit 7214f7a79 from llvm git (by Sam Elliott):

  [RISCV] Lower llvm.trap and llvm.debugtrap

  Summary:
  Until this commit, these have lowered to a call to abort().

  `llvm.trap()` now lowers to `unimp`, which should trap on all systems.

  `llvm.debugtrap()` now lowers to `ebreak`, which is exactly what this
  instruction is for.

  Reviewers: asb, luismarques

  Reviewed By: asb

  Tags: #llvm

  Differential Revision: https://reviews.llvm.org/D69390

This fixes miscompilation resulting in linking failures with
INVARIANTS disabled.

Reviewed by:	dim
Differential Revision:	https://reviews.freebsd.org/D23857

MFC r358851:

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
10.0.0-rc3 c290cb61fdc.

Release notes for llvm, clang, lld and libc++ 10.0.0 will become
available here:

https://releases.llvm.org/10.0.0/docs/ReleaseNotes.html
https://releases.llvm.org/10.0.0/tools/clang/docs/ReleaseNotes.html
https://releases.llvm.org/10.0.0/tools/lld/docs/ReleaseNotes.html
https://releases.llvm.org/10.0.0/projects/libcxx/docs/ReleaseNotes.html

PR:		244251

MFC r358854:

Add one additional file to libllvmminimal, to help the ppc64 bootstrap.

Reported by:	bdragon
PR:		244251

MFC r358857:

Move another file in libllvm from sources required for world, to sources
required for bootstrap, as the PowerPC builds need this.

Reported by:	bdragon
PR:		244251

MFC r358907:

Allow -DNO_CLEAN build across r358851.

The openmp 10.0.0 import renamed one .c file to .cpp, and this is
something our dependency system does not handle correctly.  Add another
ad-hoc cleanup to get rid of the stale dependency.

PR:		244251

MFC r358909 (by emaste):

Extend r358907 to explicitly remove stale lib32 dependency

After r325072 stale lib32 dependencies were not remooved.  A more
holistic approach is needed to address this but for the immediate issue
(-DNO_CLEAN builds across r358851) just readd the explicit lib32 path.

Reported by:	dim
Sponsored by:	The FreeBSD Foundation

MFC r358910 (by emaste):

Makefile.inc1: move dependency hack comment to the block it applies to

MFC r359035 (by emaste):

Makefile.inc1: add a note when deleting stale dependencies

We have ad-hoc stale dependency handling in Makefile.inc1 to handle the
cases where file extensions change, but it appears that some cases are
not functional.  Add a note when about to clean stale deps to help
when investigating failure reports.

Sponsored by:	The FreeBSD Foundation

MFC r359082:

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
llvmorg-10.0.0-rc4-5-g52c365aa9ca.  The actual release should follow Real
Soon Now.

PR:             244251
MFC after:      6 weeks

MFC r359083 (by emaste):

invoke _cleanobj_fast_depend_hack unconditionally

Apparently make ${CLEANDIR} is leaving stale entries in .depend files;
for now invoke the hacky cleanup in both the -DNO_CLEAN and normal
(no -DNO_CLEAN) cases.

In collaboration with:	dim
Sponsored by:	The FreeBSD Foundation

MFC r359084:

Merge commit 00925aadb from llvm git (by Fangrui Song):

  [ELF][PPC32] Fix canonical PLTs when the order does not match the PLT order

  Reviewed By: Bdragon28

  Differential Revision: https://reviews.llvm.org/D75394

This is needed to fix miscompiled canonical PLTs on ppc32/lld10.

Requested by:	bdragon
Differential Revision: https://reviews.freebsd.org/D24109

MFC r359085:

Merge commit 315f8a55f from llvm git (by Fangrui Song):

  [ELF][PPC32] Don't report "relocation refers to a discarded section"
  for .got2

  Similar to D63182 [ELF][PPC64] Don't report "relocation refers to a
  discarded section" for .toc

  Reviewed By: Bdragon28

  Differential Revision: https://reviews.llvm.org/D75419

This is needed to fix compile errors when building for ppc32/lld10.

Requested by:	bdragon
Differential Revision: https://reviews.freebsd.org/D24110

MFC r359086:

Merge commit b8ebc11f0 from llvm git (by Sanjay Patel):

  [EarlyCSE] avoid crashing when detecting min/max/abs patterns (PR41083)

  As discussed in PR41083:
  https://bugs.llvm.org/show_bug.cgi?id=41083
  ...we can assert/crash in EarlyCSE using the current hashing scheme
  and instructions with flags.

  ValueTracking's matchSelectPattern() may rely on overflow (nsw, etc)
  or other flags when detecting patterns such as min/max/abs composed
  of compare+select. But the value numbering / hashing mechanism used
  by EarlyCSE intersects those flags to allow more CSE.

  Several alternatives to solve this are discussed in the bug report.
  This patch avoids the issue by doing simple matching of min/max/abs
  patterns that never requires instruction flags. We give up some CSE
  power because of that, but that is not expected to result in much
  actual performance difference because InstCombine will canonicalize
  these patterns when possible. It even has this comment for abs/nabs:

    /// Canonicalize all these variants to 1 pattern.
    /// This makes CSE more likely.

  (And this patch adds PhaseOrdering tests to verify that the expected
  transforms are still happening in the standard optimization
  pipelines.

  I left this code to use ValueTracking's "flavor" enum values, so we
  don't have to change the callers' code. If we decide to go back to
  using the ValueTracking call (by changing the hashing algorithm
  instead), it should be obvious how to replace this chunk.

  Differential Revision: https://reviews.llvm.org/D74285

This fixes an assertion when building the math/gsl port on PowerPC64.

Requested by:	pkubja

MFC r359087:

Merge commit 585a3cc31 from llvm git (by me):

  Fix -Wdeprecated-copy-dtor and -Wdeprecated-dynamic-exception-spec
  warnings.

  Summary:
  The former are like:

  libcxx/include/typeinfo:322:11: warning: definition of implicit copy
  constructor for 'bad_cast' is deprecated because it has a
  user-declared destructor [-Wdeprecated-copy-dtor]
    virtual ~bad_cast() _NOEXCEPT;
	    ^
  libcxx/include/typeinfo:344:11: note: in implicit copy constructor
  for 'std::bad_cast' first required here
      throw bad_cast();
	    ^

  Fix these by adding an explicitly defaulted copy constructor.

  The latter are like:

  libcxx/include/codecvt:105:37: warning: dynamic exception
  specifications are deprecated [-Wdeprecated-dynamic-exception-spec]
      virtual int do_encoding() const throw();
				      ^~~~~~~

  Fix these by using the _NOEXCEPT macro instead.

  Reviewers: EricWF, mclow.lists, ldionne, #libc

  Reviewed By: EricWF, #libc

  Subscribers: dexonsmith, libcxx-commits

  Tags: #libc

  Differential Revision: https://reviews.llvm.org/D76150

This is because we use -Wsystem-headers during buildworld, and the two
warnings above are now triggered by default with clang 10, preventing
most C++ code from compiling without NO_WERROR.

Requested by:	brooks
Differential Revision: https://reviews.freebsd.org/D24049

MFC r359089 (by emaste):

Revert r359083, fixed properly by r359088

r359083 introduced a workaround for stale libomp dependencies during a
regular (no -DNO_CLEAN) buildworld.  r359088 addressed the reason the
clean step missed libomp, so revert the workaround.

Sponsored by:	The FreeBSD Foundation

MFC r359333:

Merge commit f0990e104 from llvm git (by Justin Hibbits):

  [PowerPC]: e500 target can't use lwsync, use msync instead

  The e500 core has a silicon bug that triggers an illegal instruction
  program trap on any sync other than msync. Other cores will typically
  ignore illegal sync types, and the documentation even implies that
  the 'illegal' bits are ignored.

  Address this hardware deficiency by only using msync, like the PPC440.

  Differential Revision:  https://reviews.llvm.org/D76614

Requested by:	jhibbits

MFC r359334:

Merge commit 459e8e948 from llvm git (by Justin Hibbits):

  [PowerPC]: Don't allow r0 as a target for LD_GOT_TPREL_L/32

  Summary:
  The linker is free to relax this (relocation R_PPC_GOT_TPREL16)
  against R_PPC_TLS, if it sees fit (initial exec to local exec). If r0
  is used, this can generate execution-invalid code (converts to 'addi
  %rX, %r0, FOO, which translates in PPC-lingo to li %rX, FOO). Forbid
  this instead.

  This fixes static binaries using locales on FreeBSD/powerpc (tested
  on FreeBSD/powerpcspe).

  Reviewed By: nemanjai
  Differential Revision: https://reviews.llvm.org/D76662

Requested by:	jhibbits

MFC r359338:

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
llvmorg-10.0.0-0-gd32170dbd5b (aka 10.0.0 release).

PR:		244251

MFC r359506 (by emaste):

lldb: stop excluding bindings/ subdir

With liblua in the tree we should be able to enable lldb's lua
scripting.  We'll need the files in bindings/, so start by allowing them
to come in with the next import.

Approved by:	dim
Sponsored by:	The FreeBSD Foundation

MFC r359578:

Merge once more from ^/vendor/llvm-project/release-10.x, to get the
lldb/bindings directory, which will be used to provide lua bindings for
lldb.

Requested by:	emaste

MFC r359826:

Merge commit 30588a739 from llvm git (by Erich Keane):

  Make target features check work with ctor and dtor-

  The problem was reported in PR45468, applying target features to an
  always_inline constructor/destructor runs afoul of GlobalDecl
  construction assert when checking for target-feature compatibility.

  The core problem is fixed by using the version of the check that
  takes a FunctionDecl rather than the GlobalDecl. However, while
  writing the test, I discovered that source locations weren't properly
  set for this check on ctors/dtors. This patch also fixes constructors
  and CALLED destructors.

  Unfortunately, it doesn't seem too possible to get a meaningful
  source location for a 'cleanup' destructor, so those are still
  'frontend' level errors unfortunately. A fixme was added to the test
  to cover that situation.

This should fix 'Assertion failed: (!isa<CXXConstructorDecl>(D) && "Use
other ctor with ctor decls!"), function Init, file
/usr/src/contrib/llvm-project/clang/include/clang/AST/GlobalDecl.h, line
45' when compiling the security/botan2 port.

PR:		245550

MFC r359981:

Revert commit a9ad65a2b from llvm git (by Nemanja Ivanovic):

  [PowerPC] Change default for unaligned FP access for older subtargets

  This is a fix for https://bugs.llvm.org/show_bug.cgi?id=40554

  Some CPU's trap to the kernel on unaligned floating point access and
  there are kernels that do not handle the interrupt. The program then
  fails with a SIGBUS according to the PR. This just switches the
  default for unaligned access to only allow it on recent server CPUs
  that are known to allow this.

  Differential revision: https://reviews.llvm.org/D71954

This upstream commit causes a compiler hang when building certain ports
(e.g. security/nss, multimedia/x264) for powerpc64.  The hang has been
reported in https://bugs.llvm.org/show_bug.cgi?id=45186, but in the mean
time it is more convenient to revert the commit.

Requested by:	jhibbits

MFC r359994:

Revert commit b6cf400aa fro llvm git (by Nemanja Ivanovic):

  Fix bots after a9ad65a2b34f

  In the last commit, I neglected to initialize the new subtarget
  feature I added which caused failures on a few bots. This should fix
  that.

This unbreaks the build after r359981, which reverted upstream commit
a9ad65a2b34f.

Reported by:	jhibbits (and jenkins :)

MFC r360129:

Merge commit ce5173c0e from llvm git (by Reid Kleckner):

  Use FinishThunk to finish musttail thunks

  FinishThunk, and the invariant of setting and then unsetting
  CurCodeDecl, was added in 7f416cc42638 (2015). The invariant didn't
  exist when I added this musttail codepath in ab2090d10765 (2014).
  Recently in 28328c3771, I started using this codepath on non-Windows
  platforms, and users reported problems during release testing
  (PR44987).

  The issue was already present for users of EH on i686-windows-msvc,
  so I added a test for that case as well.

  Reviewed By: hans

  Differential Revision: https://reviews.llvm.org/D76444

This should fix 'Assertion failed: (!empty() && "popping exception stack
when not empty"), function popTerminate, file
/usr/src/contrib/llvm-project/clang/lib/CodeGen/CGCleanup.h, line 583'
when building the net-p2p/libtorrent-rasterbar

PR:		244830
Reported by:	jbeich, yuri

MFC r360134:

Merge commit 64b31d96d from llvm git (by Nemanja Ivanovic):

  [PowerPC] Do not attempt to reuse load for 64-bit FP_TO_UINT without
  FPCVT

  We call the function that attempts to reuse the conversion without
  checking whether the target matches the constraints that the callee
  expects. This patch adds the check prior to the call.

  Fixes: https://bugs.llvm.org/show_bug.cgi?id=43976
  Differential revision: https://reviews.llvm.org/D77564

This should fix 'Assertion failed: ((Op.getOpcode() == ISD::FP_TO_SINT
|| Subtarget.hasFPCVT()) && "i64 FP_TO_UINT is supported only with
FPCVT"), function LowerFP_TO_INTForReuse, file
/usr/src/contrib/llvm/lib/Target/PowerPC/PPCISelLowering.cpp, line 7276'
when building the devel/libslang2 port (and a few others) for PowerPC64.

Requested by:	pkubaj

MFC r360350:

Tentatively apply https://reviews.llvm.org/D78877 (by Dave Green):

  [ARM] Only produce qadd8b under hasV6Ops

  When compiling for a arm5te cpu from clang, the +dsp attribute is
  set. This meant we could try and generate qadd8 instructions where we
  would end up having no pattern. I've changed the condition here to be
  hasV6Ops && hasDSP, which is what other parts of ARMISelLowering seem
  to use for similar instructions.

  Fixed PR45677.

This fixes "fatal error: error in backend: Cannot select: t37: i32 =
ARMISD::QADD8b t43, t44" when compiling sys/dev/sound/pcm/feeder_mixer.c
for armv5. For some reason we do not encounter this on head, but this
error popped up while building universes for stable/12.