Changes

Correctly track GCOVProfiling IR update

Differential Revision: https://reviews.llvm.org/D82742

[ARM][LowOverheadLoops] Handle reductions

While validating live-out values, record instructions that look like
a reduction. This will comprise of a vector op (for now only vadd),
a vorr (vmov) which store the previous value of vadd and then a vpsel
in the exit block which is predicated upon a vctp. This vctp will
combine the last two iterations using the vmov and vadd into a vector
which can then be consumed by a vaddv.

Once we have determined that it's safe to perform tail-predication,
we need to change this sequence of instructions so that the
predication doesn't produce incorrect code. This involves changing
the register allocation of the vadd so it updates itself and the
predication on the final iteration will not update the falsely
predicated lanes. This mimics what the vmov, vctp and vpsel do and
so we then don't need any of those instructions.

Differential Revision: https://reviews.llvm.org/D75533

[AMDGPU] Spill more than wavesize CSR SGPRs

In case of more than wavesize CSR SGPR spills, lanes of reserved VGPR were getting
overwritten due to wrap around.

Reserve a VGPR (when NumVGPRSpillLanes = 0, WaveSize, 2*WaveSize, ..) and when one
of the two conditions is true:
 1. One reserved VGPR being tracked by VGPRReservedForSGPRSpill is not yet reserved.
 2. All spill lanes of reserved VGPR(s) are full and another spill lane is required.

Reviewed By: arsenm, kerbowa

Differential Revision: https://reviews.llvm.org/D82463

[ThinLTO] Always parse module level inline asm with At&t dialect (PR46503)

clang-cl passes -x86-asm-syntax=intel to the cc1 invocation so that
assembly listings produced by the /FA flag are printed in Intel dialect.
That flag however should not affect the *parsing* of inline assembly in
the program. (See r322652)

When compiling normally, AsmPrinter::emitInlineAsm is used for
assembling and defaults to At&t dialect. However, when compiling for
ThinLTO, the code which parses module level inline asm to find symbols
for the symbol table was failing to set the dialect. This patch fixes
that. (See the bug for more details.)

Differential revision: https://reviews.llvm.org/D82862

[clangd] Config: compile Fragment -> CompiledFragment -> Config

Subscribers: mgorny, ilya-biryukov, MaskRay, jkorous, arphaman, kadircet, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D82612

[analyzer][CrossTU] Lower CTUImportThreshold default value

Summary:
The default value of 100 makes the analysis slow. Projects of considerable
size can take more time to finish than it is practical. The new default
setting of 8 is based on the analysis of LLVM itself. With the old default
value of 100 the analysis time was over a magnitude slower. Thresholding the
load of ASTUnits is to be extended in the future with a more fine-tuneable
solution that accomodates to the specifics of the project analyzed.

Reviewers: martong, balazske, Szelethus

Subscribers: whisperity, xazax.hun, baloghadamsoftware, szepet, rnkovacs, a.sidorin, mikhail.ramalho, Szelethus, donat.nagy, dkrupp, Charusso, steakhal, ASDenysPetrov, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D82561

[gn build] Port f12cd99c440

[SVE] Relax merge requirement for IR based divides.

We currently lower SDIV to SDIV_MERGE_OP1. This forces the value
for inactive lanes in a way that can hamper register allocation,
however, the lowering has no requirement for inactive lanes.

Instead this patch replaces SDIV_MERGE_OP1 with SDIV_PRED thus
freeing the register allocator. Once done the only user of
SDIV_MERGE_OP1 is intrinsic lowering so I've removed the node
and perform ISel on the intrinsic directly. This also allows
us to implement MOVPRFX based zeroing in the same manner as SUB.

This patch also renames UDIV_MERGE_OP1 and [F]ADD_MERGE_OP1 for
the same reason but in the ADD cases the ISel code is already
as required.

Differential Revision: https://reviews.llvm.org/D82783

[AMDGPU] Correct AMDGPUUsage.rst DW_AT_LLVM_lane_pc example

- Correct typo of DW_OP_xaddr to DW_OP_addrx in AMDGPUUsage.rst for
  DW_AT_LLVM_lane_pc example.

Change-Id: I1b0ee2b24362a0240388e4c2f044c1d4883509b9

[NFC][ARM] Add test.

[lldb] Scalar re-fix UB in float->int conversions

The refactor in 48ca15592f1 reintroduced UB when converting out-of-bounds
floating point numbers to integers -- the behavior for ULongLong() was
originally fixed in r341685, but did not survive my refactor because I
based my template code on one of the methods which did not have this
fix.

This time, I apply the fix to all float->int conversions, instead of
just the "double->unsigned long long" case. I also use a slightly
simpler version of the code, with fewer round-trips
(APFloat->APSInt->native_int vs
APFloat->native_float->APInt->native_int).

I also add some unit tests for the conversions.

[Alignment][NFC] Migrate MachineFrameInfo::CreateSpillStackObject to Align

iThis patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Differential Revision: https://reviews.llvm.org/D82934

[DebugInfo] Do not emit entry values for composite locations

Summary:
This is a fix for PR45009.

When working on D67492 I made DwarfExpression emit a single
DW_OP_entry_value operation covering the whole composite location
description that is produced if a register does not have a valid DWARF
number, and is instead composed of multiple register pieces. Looking
closer at the standard, this appears to not be valid DWARF. A
DW_OP_entry_value operation's block can only be a DWARF expression or a
register location description, so it appears to not be valid for it to
hold a composite location description like that.

See DWARFv5 sec. 2.5.1.7:

"The DW_OP_entry_value operation pushes the value that the described
 location held upon entering the current subprogram. It has two
 operands: an unsigned LEB128 length, followed by a block containing a
 DWARF expression or a register location description (see Section
 2.6.1.1.3 on page 39)."

Here is a dwarf-discuss mail thread regarding this:

http://lists.dwarfstd.org/pipermail/dwarf-discuss-dwarfstd.org/2020-March/004610.html

There was not a strong consensus reached there, but people seem to lean
towards that operations specified under 2.6 (e.g. DW_OP_piece) may not
be part of a DWARF expression, and thus the DW_OP_entry_value operation
can't contain those.

Perhaps we instead want to emit a entry value operation per each
DW_OP_reg* operation, e.g.:

  - DW_OP_entry_value(DW_OP_regx sub_reg0),
    DW_OP_stack_value,
    DW_OP_piece 8,
  - DW_OP_entry_value(DW_OP_regx sub_reg1),
    DW_OP_stack_value,
    DW_OP_piece 8,
  [...]

The question then becomes how the call site should look; should a
composite location description be emitted there, and we then leave it up
to the debugger to match those two composite location descriptions?
Another alternative could be to emit a call site parameter entry for
each sub-register, but firstly I'm unsure if that is even valid DWARF,
and secondly it seems like that would complicate the collection of call
site values quite a bit. As far as I can tell GCC does not emit any
entry values / call sites in these cases, so we do not have something to
compare with, but the former seems like the more reasonable approach.

Currently when trying to emit a call site entry for a parameter composed
of multiple DWARF registers a (DwarfRegs.size() == 1) assert is
triggered in addMachineRegExpression(). Until the call site
representation is figured out, and until there is use for these entry
values in practice, this commit simply stops the invalid DWARF from
being emitted.

Reviewers: djtodoro, vsk, aprantl

Reviewed By: djtodoro, vsk

Subscribers: jyknight, hiraditya, fedor.sergeev, jrtc27, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D75270

[llvm-readobj] - Simplify and refine hash table tests

Now we are able to have default values for macros in YAML descriptions.
I've applied it for hash table tests and also fixed few copy-paste issues
in their comments.

Differential revision: https://reviews.llvm.org/D82870

[llvm-readobj] - Don't crash when checking the number of dynamic symbols.

When we deriving the number of symbols from the DT_HASH table, we can crash when
calculate the number of symbols in the symbol table when SHT_DYNSYM
has sh_entsize == 0.

The patch fixes the issue.

Differential revision: https://reviews.llvm.org/D82877

[clangd] Fix name conflict again, unbreak GCC. NFC