Summary:
This is collaboration between Marcel Boehme @ Monash, Australia and Valentin Manès plus Sang Kil Cha @ KAIST, South Korea.

We have made a few modifications to boost LibFuzzer performance by changing how weights are assigned to the seeds in the corpus. Essentially, seeds that reveal more "information" about globally rare features are assigned a higher weight. Our results on the Fuzzer Test Suite seem quite promising. In terms of bug finding, our Entropic patch usually finds the same errors much faster and in more runs. In terms of coverage, our version Entropic achieves the same coverage in less than half the time for the majority of subjects. For the lack of space, we shared more detailed performance results directly with @kcc. We'll publish the preprint with all the technical details as soon as it is accepted. Happy to share if you drop us an email.

There should be plenty of opportunities to optimise further. For instance, while Entropic achieves the same coverage in less than half the time, Entropic has a much lower #execs per second. We ran the perf-tool and found a few performance bottlenecks.

Thanks for open-sourcing LibFuzzer (and the entire LLVM Compiler Infrastructure)! This has been such a tremendous help to my research.

Patch By: Marcel Boehme

Reviewers: kcc, metzman, morehouse, Dor1s, vitalybuka

Reviewed By: kcc

Subscribers: dgg5503, Valentin, llvm-commits, kcc

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73776

This effectively splits the scheduling WriteVecMaskedStore(Y) classes
into four different classes (one per each variant).

The new VecMaskedStore scheduling classes are now correctly marked as
'unsupported' by the bdver2 and btver2 models.

No functional change intended.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D80201

We already check hasNoNaNs and that x is finite and strictly positive.
That only leaves the following special cases (taken from the Linux man
page for pow):

If x is +1, the result is 1.0 (even if y is a NaN).
If the absolute value of x is less than 1, and y is negative infinity, the result is positive infinity.
If the absolute value of x is greater than 1, and y is negative infinity, the result is +0.
If the absolute value of x is less than 1, and y is positive infinity, the result is +0.
If the absolute value of x is greater than 1, and y is positive infinity, the result is positive infinity.

The first case is handled elsewhere, and this transformation preserves
all the others, so there is no need to limit it to hasNoInfs.

Differential Revision: https://reviews.llvm.org/D79409

Note, we still name a preempted SharedSymbol "shared definition",
instead of "reference" as printed by GNU ld. This difference should not matter.

```
// GNU ld
ld.bfd: t: definition of f@v1
ld.bfd: t.so: reference to f@v1
```

Reviewed By: psmith

Differential Revision: https://reviews.llvm.org/D80143

[clang-format] @lefticus just taught the world how to use [[unlikely]] but we forgot to teach clang-format

Summary:
https://twitter.com/lefticus/status/1262392152950288384?s=20

Jason Turner's (@lefticus) most recent C++ weekly explains the usage of [[likely]] and [[unlikely]] in an 'if/else' context in C++ 20

clang-format leaves the code a little messy afterwards..

```
if (argc > 5)
  [[unlikely]] {
    // ...
  }
else if (argc < 0)
  [[likely]] {
    // ...
  }
else
  [[likely]] {
    // ...
  }
```

try to improve the situation

```
if (argc > 5) [[unlikely]] {
  // ...
} else if (argc < 0) [[likely]] {
  // ...
} else [[likely]] {
  // ...
}
```

Reviewed By: JakeMerdichAMD

Subscribers: cfe-commits, lefticus

Tags: #clang, #clang-format

Differential Revision: https://reviews.llvm.org/D80144

[clang-format] [PR45614] Incorrectly indents [[nodiscard]] attribute funtions after a macro without semicolon

Summary:
https://bugs.llvm.org/show_bug.cgi?id=45614

`[[nodiscard]]` after a macro doesn't behave the same as an __attribute__ resulting in incorrect indentation

This revision corrects that behavior

See original Mozilla bug:
https://bugzilla.mozilla.org/show_bug.cgi?id=1629756

Before:

```
class FooWidget : public nsBaseWidget {
public:
  FooWidget();

  NS_DECL_ISUPPORTS_INHERITED

      [[nodiscard]] nsresult
      FunctionOne();
  [[nodiscard]] nsresult FunctionTwo();
};
```

After:
```
class FooWidget : public nsBaseWidget {
public:
  FooWidget();

  NS_DECL_ISUPPORTS_INHERITED

  [[nodiscard]] nsresult FunctionOne();
  [[nodiscard]] nsresult FunctionTwo();
};
```

Reviewed By: Abpostelnicu

Subscribers: cfe-commits

Tags: #clang, #clang-format

Differential Revision: https://reviews.llvm.org/D79990

Summary:
https://bugs.llvm.org/show_bug.cgi?id=44476

```template <typename T> [[nodiscard]] int a() { return 1; }```

gets incorrectly formatted to be

```template <typename T>[[nodiscard]] int a() { return 1; }```

This revision ensure there is a space between the template and the attribute

Reviewed By: JakeMerdichAMD

Subscribers: cfe-commits

Tags: #clang, #clang-format

Differential Revision: https://reviews.llvm.org/D79905

Summary:
https://bugs.llvm.org/show_bug.cgi?id=45942

With Chromium style (although that is not important) its just it defines PointerAligmment: Left

The following arguments `S&&` are formatted differently depending on if the class has an attribute between it and the class identifier

```
class S {
  S(S&&) = default;
};

class [[nodiscard]] S {
  S(S &&) = default;
};
```

The prescense of [[nodiscard]] between the `class/struct` and the `{` causes the `{` to be incorrectly seen as a `TT_FunctionLBrace` which in turn transforms all the && to be `TT_BinaryOperators` rather than `TT_PointerOrReference`, as binary operators other spacing rules come into play causing a miss format

This revision resolves this by allowing the parseRecord to consider the [[nodisscard]]

Reviewed By: Abpostelnicu

Subscribers: cfe-commits

Tags: #clang, #clang-format

Differential Revision: https://reviews.llvm.org/D80008

Due to build breakage mentioned in https://reviews.llvm.org/D79926.

This reverts commit e270b2f1.

This reverts commit 1f820e35.

Summary:
YAML serialization was used in the Proof of Concept for simplicity.
This patch replaces implements Protobuf (de) serialization of almost all
types that need to be transferred over the protocol.

Reviewers: sammccall

Reviewed By: sammccall

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

Tags: #clang

Differential Revision: https://reviews.llvm.org/D79862

[MLIR] Update the FunctionAndBlockSignatureConverter and NonVoidToVoidReturnOpConverter of Buffer Assignment

Making these two converters more generic. FunctionAndBlockSignatureConverter now
moves only memref results (after type conversion) to the function argument and
keeps other legal function results unchanged. NonVoidToVoidReturnOpConverter is
renamed to NoBufferOperandsReturnOpConverter. It removes only the buffer
operands from the operands of the converted ReturnOp and inserts CopyOps to copy
each buffer to the target function argument.

Differential Revision: https://reviews.llvm.org/D79329

Differential Revision: https://reviews.llvm.org/D78122

Summary:
Created AIXABIInfo and AIXTargetCodeGenInfo for AIX ABI.

Reviewed By: Xiangling_L, ZarkoCA

Differential Revision: https://reviews.llvm.org/D79035

I think anyone who added a checker config wondered why is there a need
to test this. Its just a chore when adding a new config, so I removed
it.

To give some historic insight though, we used to not list **all**
options, but only those explicitly added to AnalyzerOptions, such as the
ones specified on the command line. However, past this change (and
arguably even before that) this line makes little sense.

There is an argument to be made against the entirety of
analyzer-config.c test file, but since this commit fixes some builtbots
and is landing without review, I wouldn't like to be too invasive.

Summary:
This means they're renamable and textDocument/highlight works

This fell out of D78454

Reviewers: adamcz

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

Tags: #clang

Differential Revision: https://reviews.llvm.org/D80170

Note that it's only used for non-pc-relative contexts.

Reviewed By: MaskRay, smeenai

Differential Revision: https://reviews.llvm.org/D80048

This diff restores and builds upon @pcc and @ruiu's initial work on
subsections.

The .subsections_via_symbols directive indicates we can split each
section along symbol boundaries, unless those symbols have been marked
with `.alt_entry`.

We exercise this functionality in our tests by using order files that
rearrange those symbols.

Reviewed By: smeenai

Differential Revision: https://reviews.llvm.org/D79926

The order file indicates how input sections should be sorted within each
output section, based on the symbols contained within those sections.

This diff sets the stage for implementing and testing
`.subsections_via_symbols`, where we will break up InputSections by each
symbol and sort them more granularly.

Reviewed By: smeenai

Differential Revision: https://reviews.llvm.org/D79668

The comment was referring the arguments of the call, but the recipe
widens a select.

Thanks to a recent change that made `::build` functions take an instance of
`OpBuilder`, it is now possible to build operations within a region attached to
the operation about to be created. Exercise this on `scf::ForOp` by taking a
callback that populates the loop body while the loop is being created.

Additionally, provide helper functions to build perfect nests of `ForOp`s,
with support for iteration arguments. These functions provide the same
functionality as EDSC LoopNestBuilder with simpler implementation, without
relying on edsc::ScopedContext, and using `OpBuilder` in an unambiguous way.
Compatibility functions for EDSC are provided, but may be removed in the
future.

Differential Revision: https://reviews.llvm.org/D79688

Under `lld/test/Driver/Inputs/`, all instances of `libtest.a` are
unreferenced. FYI, all of these are empty archives, and the files
contain only a magic number.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D80182

Replace with MCTargetOptions forward declaration and move includes down to MCTargetOptionsCommandFlags.cpp

We already have to include raw_ostream.h.

Don't explicitly include ilist_node.h + simple_ilist.h - we already include ilist.h that include these for us and all references are in terms of that.

The rest can be covered by forward declarations.

Differential Revision: https://reviews.llvm.org/D80211

This patch adds VPValue version of the instruction operands to
VPReplicateRecipe and uses them during code-generation.

Reviewers: Ayal, gilr, rengolin

Reviewed By: gilr

Differential Revision: https://reviews.llvm.org/D80114

We can remove a dynamic memory allocation, by checking the number of
operands: no operands = all true, 1 operand = mask.

Reviewers: Ayal, gilr, rengolin

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D80110

This was assuming a select is always an instruction, which is not
true.

[analyzer][DirectIvarAssignment] Turn DirectIvarAssignmentForAnnotatedFunctions into a checker option

Since this is an alpha checker, I don't worry about backward compatibility :)

Differential Revision: https://reviews.llvm.org/D78121

Summary:
FieldDecl::getParent assumes that the FiledDecl::getDeclContext returns a
RecordDecl, this is true for C/C++, but not for ObjCIvarDecl:

The Decls hierarchy is like following

FieldDecl <-- ObjCIvarDecl

DeclContext <-- ObjCContainerDecl <-- ObjCInterfaceDecl
         ^
         |----- TagDecl <-- RecordDecl

calling getParent() on ObjCIvarDecl will:
1. invoke getDeclContext(), which returns a DeclContext*, which points to an ObjCInterfaceDecl;
2. then downcast the "DeclContext" pointer to a RecordDecl*, and we will hit
the "is_a<RecordDecl>" assertion in llvm::cast (undefined behavior
in release build without assertion enabled);

Fixes https://github.com/clangd/clangd/issues/369

Reviewers: sammccall

Reviewed By: sammccall

Subscribers: rsmith, jkorous, arphaman, kadircet, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D79627

Reviewers: sammccall

Reviewed By: sammccall

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

Tags: #clang

Differential Revision: https://reviews.llvm.org/D79938

Summary:
Similar to property, we print the containing interface decl as the
nested name specifier for ivar; otherwise we will get "::ivar_name".

this would fix an assertion crash in clangd: https://github.com/clangd/clangd/issues/365

Reviewers: sammccall

Reviewed By: sammccall

Subscribers: ilya-biryukov, kadircet, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D79576

Implemented tangent op from SPIR-V's GLSL extended instruction set.
Added a round-trip and serialization/deserialization tests for the op.

Differential Revision: https://reviews.llvm.org/D80152

Summary:
With recovery expr, it is possible that we have a value-dependent expr
within non-dependent context.

Reviewers: sammccall, jdoerfert

Subscribers: yaxunl, guansong, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D80200

Summary:
Added parsing/sema/serialization support for affinity clause in task
directives.

Reviewers: jdoerfert

Subscribers: yaxunl, guansong, arphaman, llvm-commits, cfe-commits, caomhin

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D80148