This reverts commit c64ca930.

This patch tripped a few build bots:

  http://lab.llvm.org:8011/builders/clang-x86_64-debian-fast/builds/24703/
  http://lab.llvm.org:8011/builders/clang-cmake-x86_64-avx2-linux/builds/13465/
  http://lab.llvm.org:8011/builders/clang-with-lto-ubuntu/builds/15994/

Reverting to clear the bots.

This fixes printing long values that might reside in CIE and FDE,
including offsets, lengths, and addresses.

Differential Revision: https://reviews.llvm.org/D73887

The condition was not accurate enough and could interpret some FDEs in
.eh_frame or 64-bit DWARF .debug_frame sections as CIEs. Even though
such FDEs are unlikely in a normal situation, the wrong interpretation
could hide an issue in a buggy generator.

Differential Revision: https://reviews.llvm.org/D73886

New code added in ec3060c7 looked like

+  case TemplateName::NameKind::OverloadedTemplate:
+    assert(false && "overloaded templates shouldn't survive to here.");
+  default:

If compiling without asserts we then got a warning about unannotated
fallthrough from the case into the default.

Change the assert into an llvm_unreachable to silence the warning.

by "inlining" them into their single caller (CommandObjectDisassemble).
The functions mainly consist of long argument lists and defensive
checks. These become unnecessary after inlining, so the end result is
less code. Additionally, this makes the implementation of
CommandObjectDisassemble more uniform (first figure out what you're
going to disassemble, then actually do it), which enables further
cleanups.

It fixes now what 1c991f90 tried to fix.
(A test case failture on 32-bit Arch Linux)

On 32-bit hosts it still fails (because it truncates the `Pos` value to 32 bits).
It seems happens because of `sizeof` that returns `size_t`, which has a
different size on 32/64 bits hosts.

I've tested on a 32-bit host and verified that relocation-errors.test test and
other LLVM tools tests pass now.

Revert "[ValueTracking] Let isGuaranteedNotToBeUndefOrPoison look into branch conditions of dominating blocks' terminators"

That commit causes SIGSEGV on some simple tests.
This reverts commit 952ad470.

Bug spotted by https://cookieplmonster.github.io/2020/02/01/emulator-bug-llvm-bug/

Basically, holding references to object inside a resized vector is a bad idea.

Differential Revision: https://reviews.llvm.org/D75110

When one of sub-ranges has not been move constructed into a raw buffer, we should not call clean up for that sub-range. Instead of store detailed info about raw buffer history, the fix does the cleanup a sub-range after each moving the sub-range back.

https://reviews.llvm.org/D73779

Fix-its were intentionally disabled by TestBase.setUp so that incorrect expressions in tests
don't pass just because Clang thinks it has a fix-it.

Some tests set settings and don't clean them up, this leads to side effects in other tests.
The patch removes a global debugger instance with a per-test debugger to avoid such effects.

From what I see, lldb.DBG was needed to determine the platform before a test is run,
lldb.selected_platform is used for this purpose now. Though, this required adding a new function
to the SBPlatform interface.

Differential Revision: https://reviews.llvm.org/D74903

Differential Revision: https://reviews.llvm.org/D75440

X86AsmBackend.cpp: #ifndef NDEBUG some only-used-in-asserts variables to fix the -Werror non-asserts build

The LLJIT::MachOPlatformSupport class used to unconditionally attempt to
register __objc_selrefs and __objc_classlist sections. If libobjc had not
been loaded this resulted in an assertion, even if no objc sections were
actually present. This patch replaces this unconditional registration with
a check that no objce sections are present if libobjc has not been loaded.
This will allow clients to use MachOPlatform with LLJIT without requiring
libobjc for non-objc code.

After structurization, some phi nodes can have a single incoming edge
and can be simplified away. This change runs a simplify query on all
phis that are either modified or added by the structurizer. This also
moves some phis closer to their use as a side benefit.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D75500

The original code could create a bitcast from f64 to i64 and back
on 32-bit targets. This was only working because getBitcast was
able to fold the casts away to avoid leaving the illegal i64 type.

Now we handle the scalar case directly by broadcasting using the
scalar type as the element type. Then bitcasting to the final VT.
This works since we ensure the scalar type is the same size as
the final VT element type. No more casts to i64.

For the vector case, we cast to VT or subvector of VT. And then
do the broadcast.

I think this all matches what we generated before, just in a more
readable way.

The IR hasn't switched the default yet, so explicitly add the ieee
attributes.

I'm still not really sure how the target default denormal mode should
interact with -fno-unsafe-math-optimizations. The target may have
selected the default mode to be non-IEEE based on the flags or based
on its true behavior, but we don't know which is the case. Since the
only users of a non-IEEE mode without a flag still support IEEE mode,
just reset to IEEE.

One instance in a copy paste was pointed out in a review, fix all instances at once.

Summary:
Move the check for malformed REBASE_OPCODE_ADD_ADDR_IMM_SCALED and
BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED opcodes after the immediate
has been applied to the SegmentOffset. This fixes specious errors
where SegmentOffset is pointing between two sections when trying to
correct the SegmentOffset value.

Update the regression tests to verify the proper error message.

Reviewers: pete, ab, lhames, steven_wu, jhenderson

Reviewed By: pete

Subscribers: hiraditya, dexonsmith, rupprecht, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75629

A DWARFSectionKind is read from input. It is not validated on parsing,
so an unexpected value may result in reaching llvm_unreachable() in
DWARFUnitIndex::getColumnHeader() when dumping the index section.

Differential Revision: https://reviews.llvm.org/D75609

PowerPC hits an assertion due to somewhat the same reason as https://reviews.llvm.org/D70975.
Though there are already some hack, it still failed with some case, when the operand 0 is NOT
a const fp, it is another fma that with const fp. And that const fp is negated which result in multi-uses.

A better fix is to check the uses of the negated const fp. If there are already use of its negated
value, we will have benefit as no extra Node is added.

Differential revision: https://reviews.llvm.org/D75501

Summary: Use Register type for variables instead of unsigned type.

Reviewers: dylanmckay

Reviewed By: dylanmckay

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75595

YAML files were not being run during lit testing as there was no lit.local.cfg file. Once this was fixed, some buildbots would fail due to a StringRef that pointed to a std::string inside of a temporary llvm::Triple object. These issues are fixed here by making a local triple object that stays around long enough so the StringRef points to valid data. Fixed memory sanitizer bot bugs as well.

Differential Revision: https://reviews.llvm.org/D75390

Summary: Lower trap and debugtrap intrinsics to AMDGPU machine instruction(s).

Reviewers: arsenm, nhaehnle, kerbowa, cdevadas, t-tye, kzhuravl

Reviewed By: arsenm

Subscribers: kzhuravl, jvesely, wdng, yaxunl, rovka, dstuttard, tpr, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74688

Summary: X86 can reduce the bytes of NOP by padding instructions with prefixes to get a better peformance in some cases. So a private member function `determinePaddingPrefix` is added to determine which prefix is the most suitable.

Reviewers: annita.zhang, reames, MaskRay, craig.topper, LuoYuanke, jyknight

Reviewed By: reames

Subscribers: llvm-commits, dexonsmith, hiraditya

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75357

output has zero rank.

While lowering to loops, no indices should be used in the load/store
operation if the buffer is zero-rank.

Differential Revision: https://reviews.llvm.org/D75391

If we have an explicit align directive, we currently default to emitting nops to fill the space. As discussed in the context of the prefix padding work for branch alignment (D72225), we're allowed to play other tricks such as extending the size of previous instructions instead.

This patch will convert near jumps to far jumps if doing so decreases the number of bytes of nops needed for a following align. It does so as a post-pass after relaxation is complete. It intentionally works without moving any labels or doing anything which might require another round of relaxation.

The point of this patch is mainly to mock out the approach. The optimization implemented is real, and possibly useful, but the main point is to demonstrate an approach for implementing such "pad previous instruction" approaches. The key notion in this patch is to treat padding previous instructions as an optional optimization, not as a core part of relaxation. The benefit to this is that we avoid the potential concern about increasing the distance between two labels and thus causing further potentially non-local code grown due to relaxation. The downside is that we may miss some opportunities to avoid nops.

For the moment, this patch only implements a small set of existing relaxations.. Assuming the approach is satisfactory, I plan to extend this to a broader set of instructions where there are obvious "relaxations" which are roughly performance equivalent.

Note that this patch *doesn't* change which instructions are relaxable. We may wish to explore that separately to increase optimization opportunity, but I figured that deserved it's own separate discussion.

There are possible downsides to this optimization (and all "pad previous instruction" variants). The major two are potentially increasing instruction fetch and perturbing uop caching. (i.e. the usual alignment risks) Specifically:
 * If we pad an instruction such that it crosses a fetch window (16 bytes on modern X86-64), we may cause the decoder to have to trigger a fetch it wouldn't have otherwise. This can effect both decode speed, and icache pressure.
 * Intel's uop caching have particular restrictions on instruction combinations which can fit in a particular way. By moving around instructions, we can both cause misses an change misses into hits. Many of the most painful cases are around branch density, so I don't expect this to be too bad on the whole.

On the whole, I expect to see small swings (i.e. the typical alignment change problem), but nothing major or systematic in either direction.

Differential Revision: https://reviews.llvm.org/D75203

Summary:
This ties to an LSP feature (diagnostic versioning) but really a lot
of the value is in being able to log what's happening with file versions
and queues more descriptively and clearly.

As such it's fairly invasive, for a logging patch :-\

Key decisions:
 - at the LSP layer, we don't reqire the client to provide versions (LSP
   makes it mandatory but we never enforced it). If not provided,
   versions start at 0 and increment. DraftStore handles this.
 - don't propagate magically using contexts, but rather manually:
   addDocument -> ParseInputs -> (ParsedAST, Preamble, various callbacks)
   Context-propagation would hide the versions from ClangdServer, which
   would make producing good log messages hard
 - within ClangdServer, treat versions as opaque and unordered.
   std::string is a convenient type for this, and allows richer versions
   for embedders. They're "mandatory" but "null" is a reasonable default.

Subscribers: ilya-biryukov, javed.absar, MaskRay, jkorous, arphaman, kadircet, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D75582

This reverts commit 45499f38, it's
still failing on Windows bots.

This will allow their use in member initializers in a future commit.

Summary: Decompose callThroughToSymbol() into findReexport(), resolveSymbol(), notifyResolved() and reportCallThroughError(). This allows derived classes to reuse the functionality while adding their own code in between.

Reviewers: lhames

Reviewed By: lhames

Subscribers: hiraditya, steven_wu, dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75084