(See also D76269.)

NFC.

Summary:
@labath mentioned to me that test files shouldn't have a license header.
I saw this one some days ago, so I'm doing some cleaning.

Reviewers: labath, clayborg

Subscribers: lldb-commits, labath

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D77328

Also turn on the command trace unconditionally for TestThreadPlanCommands.py as the
tests for the Ubuntu bot don't seem to run with -t making it hard to see why this is
failing remotely.

This reverts commit c74dd640.

Reverting to address coding standard issues raised in post-commit
review.

This reverts commit 62c42e29

Reverting to address coding standard issues raised in post-commit
review.

An enum may be considered to be a complete type if it was forward
declared. It may be declared with a fixed underlying type, or, in MSVC
compatiblity mode, with no type at all.

Previously, the code was written with special handling for fixed enums.
I generalized the code to check if the underlying integer type is known,
which should be the case when targetting the MSVC C++ ABI.

Fixes PR45409

Always depend on the compiler to have a correct implementation of
max_align_t in stddef.h and don't provide a fallback. For pre-C++11,
require __STDCPP_NEW_ALIGNMENT__ in <new> as provided by clang in all
standard modes. Adjust test cases to avoid testing or using max_align_t
in pre-C++11 mode and also to better deal with alignof(max_align_t)>16.
Document requirements of the alignment tests around natural alignment of
power-of-two-sized types.

Differential revision: https://reviews.llvm.org/D73245

When a category/extension doesn't repeat a type bound, corresponding
type parameter is substituted with `id` when used as a type argument. As
a result, in the added test case it was causing errors like

> type argument 'T' (aka 'id') does not satisfy the bound ('id<NSCopying>') of type parameter 'T'

We are already checking that type parameters should be consistent
everywhere (see `checkTypeParamListConsistency`) and update
`ObjCTypeParamDecl` to have correct underlying type. And when we use the
type parameter as a method return type or a method parameter type, it is
substituted to the bounded type. But when we use the type parameter as a
type argument, we check `ObjCTypeParamType` that wasn't updated and
remains `id`.

Fix by updating not only `ObjCTypeParamDecl` UnderlyingType but also
TypeForDecl as we use the underlying type to create a canonical type for
`ObjCTypeParamType` (see `ASTContext::getObjCTypeParamType`).

This is a different approach to fixing the issue. The previous one was
02c2ab3d which was reverted in
4c539e8d. The problem with the previous
approach was that `ObjCTypeParamType::desugar` was returning underlying
type for `ObjCTypeParamDecl` without applying any protocols stored in
`ObjCTypeParamType`. It caused inconsistencies in comparing types before
and after desugaring.

rdar://problem/54329242

Reviewed By: erik.pilkington

Differential Revision: https://reviews.llvm.org/D72872

clang with -flto does not handle -foptimization-record-path=<path>

This dulicates the code from ToolChains/Clang.cpp with modifications to
support everything in the same fashion.

Summary: Switched to using the new memcpy implementation.

Reviewers: sivachandra, abrachet, gchatelet

Reviewed By: abrachet, gchatelet

Subscribers: mgorny, MaskRay, tschuett, libc-commits

Tags: #libc-project

Differential Revision: https://reviews.llvm.org/D77277

Apparently the intention was to copy the condition above:
  if (types.GetSize() >= max_matches)
    break;

So that if the iteration stopped because of too many matches we do not
add even more matches in this 'Clang modules' block downward.

It was implemented by:
  SymbolFileDWARF: Unconditionally scan through clang modules. NFCish
  fe9eaadd

Differential Revision: https://reviews.llvm.org/D77336

Summary: This should fix the call to a non internal libc function.

Reviewers: sivachandra, abrachet

Reviewed By: sivachandra

Subscribers: xbolva00, mgorny, MaskRay, tschuett, libc-commits

Tags: #libc-project

Differential Revision: https://reviews.llvm.org/D77279

that were not reported by the OS plugin.  To facilitate this, move
adding/updating the ThreadPlans for a Thread to the ThreadPlanStackMap.
Also move dumping thread plans there as well.

Added some tests for "thread plan list" and "thread plan discard" since
I didn't seem to have written any originally.

Differential Revision: https://reviews.llvm.org/D76814

Differential Revision: https://reviews.llvm.org/D75880

Differential Revision: https://reviews.llvm.org/D75720

Differential Revision: https://reviews.llvm.org/D75711

Summary:
A recent extension allowed the `loop.if` operation to return results yielded by
its regions. However, such operations could not be lowered to a CFG of standard
operations because it would have required to modify the argument list of a
block, which is not allowed in a conversion pattern. Now that the conversion
infrastructure supports block creation, use it to create a block with an
argument list that dominates the operations following the `loop.if` and forward
the results as arguments of this block.

Depends On D77416

Differential Revision: https://reviews.llvm.org/D77418

When clang is built against a prebuilt LLVM, LLVM_SOURCE_DIR is
empty, which due to a cmake quirk caused list lengths to get out
of sync. Add a workaround.

Summary:
Prior to landing D76961, preprocess via:
    $ llvm/utils/update_llc_test_checks.py \
      llvm/test/CodeGen/X86/callbr-asm-outputs.ll

Reviewers: void, MaskRay

Reviewed By: void, MaskRay

Subscribers: MaskRay, llvm-commits, srhines

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77356

After finding all such gadgets in a given function, the pass minimally inserts
LFENCE instructions in such a manner that the following property is satisfied:
for all SOURCE+SINK pairs, all paths in the CFG from SOURCE to SINK contain at
least one LFENCE instruction. The algorithm that implements this minimal
insertion is influenced by an academic paper that minimally inserts memory
fences for high-performance concurrent programs:

http://www.cs.ucr.edu/~lesani/companion/oopsla15/OOPSLA15.pdf

The algorithm implemented in this pass is as follows:

1. Build a condensed CFG (i.e., a GadgetGraph) consisting only of the following components:
  -SOURCE instructions (also includes function arguments)
  -SINK instructions
  -Basic block entry points
  -Basic block terminators
  -LFENCE instructions
2. Analyze the GadgetGraph to determine which SOURCE+SINK pairs (i.e., gadgets) are already mitigated by existing LFENCEs. If all gadgets have been mitigated, go to step 6.
3. Use a heuristic or plugin to approximate minimal LFENCE insertion.
4. Insert one LFENCE along each CFG edge that was cut in step 3.
5. Go to step 2.
6. If any LFENCEs were inserted, return true from runOnFunction() to tell LLVM that the function was modified.

By default, the heuristic used in Step 3 is a greedy heuristic that avoids
inserting LFENCEs into loops unless absolutely necessary. There is also a
CLI option to load a plugin that can provide even better optimization,
inserting fewer fences, while still mitigating all of the LVI gadgets.
The plugin can be found here: https://github.com/intel/lvi-llvm-optimization-plugin,
and a description of the pass's behavior with the plugin can be found here:
https://software.intel.com/security-software-guidance/insights/optimized-mitigation-approach-load-value-injection.

Differential Revision: https://reviews.llvm.org/D75937

See rational here: https://reviews.llvm.org/D76173#1922916
Time to compile Attr.h in isolation goes from 2.6s to 1.8s.

Original patch by Johannes, plus some additions from Reid to fix some
clang tooling targets.

Effect on transitive includes is marginal, though:

$ diff -u <(sort thedeps-before.txt) <(sort thedeps-after.txt) \
   | grep '^[-+] ' | sort | uniq -c | sort -nr
    104 -    /usr/local/google/home/rnk/llvm-project/clang/include/clang/AST/OpenMPClause.h
     87 -    /usr/local/google/home/rnk/llvm-project/llvm/include/llvm/Frontend/OpenMP/OMPContext.h
     19 -    /usr/local/google/home/rnk/llvm-project/llvm/include/llvm/ADT/SmallSet.h
     19 -    /usr/local/google/home/rnk/llvm-project/llvm/include/llvm/ADT/SetVector.h
     14 -    /usr/include/c++/9/set
...

Differential Revision: https://reviews.llvm.org/D76184

Summary:
Linalg makes it possible to interface codegen with externally precompiled HPC libraries. The mechanism to allow such interop uses a normalized ABI and the emission of C interface wrappers.

The mechanism controlling these C interface emission is too aggressive and makes it very easy to obtained undefined symbols for external function (e.g. the ones coming from libm).

This revision uses the newly introduced llvm.emit_c_interface function attribute which allows controlling this behavior at a function granularity. As a consequence LinalgToLLVM does not need to activate the C wrapper emission when adding the StdToLLVM patterns.

Differential Revision: https://reviews.llvm.org/D77364

Graceful lit shutdown on user keyboard interrupt [Ctrl+C] was a
longstanding goal of mine.  After a few refactorings this revision
finally enables it.  We use the following strategy to deal with
KeyboardInterrupt:
https://noswap.com/blog/python-multiprocessing-keyboardinterrupt

Printing of a helpful summary for interrupted runs (just as the one for
completed runs) will be tackled in future revisions.

Reviewed By: serge-sans-paille, rnk

Differential Revision: https://reviews.llvm.org/D77365

Adds a new data structure, ImmutableGraph, and uses RDF to find LVI gadgets and add them to a MachineGadgetGraph.

More specifically, a new X86 machine pass finds Load Value Injection (LVI) gadgets consisting of a load from memory (i.e., SOURCE), and any operation that may transmit the value loaded from memory over a covert channel, or use the value loaded from memory to determine a branch/call target (i.e., SINK).

Also adds a new target feature to X86: +lvi-load-hardening

The feature can be added via the clang CLI using -mlvi-hardening.

Differential Revision: https://reviews.llvm.org/D75936

It is an obvious part of D77326.

It removes some needless deep indentation and some redundant statements.
It prepares the code for a more clean next patch - DWARF index callbacks
in D77327.

Revert "[PowerPC] Replace subtract-from-zero float in version with fneg in PowerPC special fma compiler builtins"

The new test case causes bot failures.

This reverts commit ba87430c.

See discussion on https://reviews.llvm.org/D77184.

Differential Revision: https://reviews.llvm.org/D76949

Summary:
This patch includes two extensions:
1. It extends the GraphDiff to also keep the original list of updates
after legalization, not just the deletes/insert vectors.
It also provides an API to pop the first update (the updates are store
in reverse, such that the first update is at the end of the list)
2. It adds a bool to mark whether the given updates should be applied as
given, or applied in reverse. This moves the task of reversing the
updates (when the caller needs this) to a functionality inside
GraphDiff, versus having the caller do this.

The two changes could be split into two patches, but they seemed
reasonably small to be reviewed together.

Reviewers: kuhar, dblaikie

Subscribers: hiraditya, george.burgess.iv, mgrang, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77167

Adding a pass that replaces every ret instruction with the sequence:

pop <scratch-reg>
lfence
jmp *<scratch-reg>

where <scratch-reg> is some available scratch register, according to the
calling convention of the function being mitigated.

Differential Revision: https://reviews.llvm.org/D75935

[PowerPC] Replace subtract-from-zero float in version with fneg in PowerPC special fma compiler builtins

This patch adds a test for the PowerPC fma compiler builtins, some variations
of which negate inputs and outputs. The code to generate IR for these
builtins was untested before this patch.

Originally, the code used the outdated method of subtracting floating point
values from -0.0 as floating point negation. This patch remedies that.

Patch by: Drew Wock <drew.wock@sas.com>
Differential Revision: https://reviews.llvm.org/D76949

Summary:
This patch fixes [[ https://bugs.llvm.org/show_bug.cgi?id=38025 | PR38025 ]]:
Wrong ABI used when building compiler-rt

Differential Revision: https://reviews.llvm.org/D74133