We already special-cased a few interesting patterns,
but that is strictly less powerful than using KnownBits.

So instead get the known bits for the operand of `and`,
and iff all the unset bits of the `and`-mask are known to be zeros
in the operand, we can omit said `and`.

If we can tell that trunc only chops off sign bits, and not all of them,
then we can simply sign-extend the trunc's source.

There are several potential srem-by-2 folds
because the result is known {-1,0,1}.

https://alive2.llvm.org/ce/z/LuVyeK

Differential Revision: https://reviews.llvm.org/D100887

MSVC linker has this [[ https://docs.microsoft.com/en-us/cpp/error-messages/tool-errors/linker-tools-warning-lnk4102?view=msvc-160 | warning]], so lld-link should also warn on this.

Differential Revision: https://reviews.llvm.org/D100606

codesign/libstuff checks that the `__LLVM` segment is directly
before `__LINKEDIT` by checking that `fileOff + fileSize == next segment
fileOff`. Previously, there would be gaps between the segments due to
the fact that their fileOffs are page-aligned but their fileSizes
aren't. In order to satisfy codesign, we page-align fileOff *before*
calculating fileSize. (I don't think codesign checks for the relative
ordering of other segments, so in theory we could do this just for
`__LLVM`, but ld64 seems to do it for all segments.)

Note that we *don't* round up the fileSize of the `__LINKEDIT` segment.
Since it's the last segment, it doesn't need to worry about contiguity;
in addition, codesign checks that the last (hidden) section in
`__LINKEDIT` covers the last byte of the segment, so if we rounded up
`__LINKEDIT`'s size we would have to do the same for its last section,
which is a bother.

While at it, I also addressed a FIXME in the linkedit-contiguity.s test
to cover more `__LINKEDIT` sections.

Reviewed By: #lld-macho, thakis, alexshap

Differential Revision: https://reviews.llvm.org/D100848

The minuend (but not the subtrahend) can reference a section.

Note that we do not yet properly validate that the subtrahend isn't
referencing a section; I've filed PR50034 to track that.

I've also extended the reloc-subtractor.s test to reorder symbols, to
make sure that the addends are being associated with the minuend (and not
the subtrahend) relocation.

Fixes PR49999.

Reviewed By: #lld-macho, thakis

Differential Revision: https://reviews.llvm.org/D100804

Introduced the cost of thre reverse shuffles for AArch64, currently just
copied the costs for PermuteSingleSrc.

Differential Revision: https://reviews.llvm.org/D100871

This is another attempt to address the issue introduced in
ae8b2cab.

We cannot capture InstalledDir because FileCheck doesn't handle
the backslashes correctly, so instead we just consume the entire
path prefix which is what other tests are doing.

This addresses Windows breakage introduced by
ae8b2cab.

I'd reverted this in commit 3b6acb17 due to buildbot failures.  This patch contains the fix for said issue.  I'd forgotten to handle the case where two phis in the same block have different operand order.  We canonicalize away from this, but it's still valid IR.  The tests included in this change (as opposed to simply having test output changed), crashed without the fix.

Original commit message follows...

This extends the phi handling in isKnownNonEqual with a special case based on invertible recurrences. If we can prove the recurrence is invertible (which many common ones are), we can recurse through the start operands of the recurrence skipping the phi cycle.

(Side note: Instcombine currently does not push back through these cases. I will implement that in a follow up change w/separate review.)

Differential Revision: https://reviews.llvm.org/D99912

We were erroneously emitting error messages for assignments of derived types
where the associated objects were instantiated with non-constant LEN type
parameters.

I fixed this by adding the member function MightBeAssignmentCompatibleWith() to
the class DerivedTypeSpec and calling it to determine whether it's possible
that objects of parameterized derived types can be assigned to each other.  Its
implementation first compares the uninstantiated values of the types.  If they
are equal, it then compares the values of the constant instantiated type
parameters.

I added tests to assign04.f90 to exercise this new code.

Differential Revision: https://reviews.llvm.org/D100868

... to only print when that fallback actually happens.

af7925b4 added a custom DAG combine for recognizing fp-to-ints of
extract_subvectors that could be lowered to f64x2.convert_low_i32x4_{s,u}
instructions. This commit extends the combines to recognize equivalent
extract_subvectors of fp-to-ints as well.

Differential Revision: https://reviews.llvm.org/D100790

Darwin driver currently uses libc++ headers that are part of Clang
toolchain when available (by default ../include/c++/v1 relative to
executable), but it completely ignores the libc++ library itself
because it doesn't pass the location of libc++ library that's part
of Clang (by default ../lib relative to the exceutable) to the linker
always using the system copy of libc++.

This may lead to subtle issues when the compilation fails because the
headers that are part of Clang toolchain are incompatible with the
system library. Either the driver should ignore both headers as well as
the library, or it should always try to use both when available.

This patch changes the driver behavior to do the latter which seems more
reasonable, it makes it easy to test and use custom libc++ build on
Darwin while still allowing the use of system version. This also matches
the Clang driver behavior on other systems.

Differential Revision: https://reviews.llvm.org/D45639

...to remove double negation in the code. Requested in D100583.

No behavior change.

Differential Revision: https://reviews.llvm.org/D100849

Define APIs for, and implement, these three more recently-introduced
standard reduction transformational intrinsic functions to the runtime.

Differential Revision: https://reviews.llvm.org/D100863

Landing this fix for Augusto Noronha.  The code is getting the
Section from 'addr' passed in, but it may have been expressed as
a load address when it was created and Target::ReadMemory tries to
convert it to a Section+offset if that's now possible; use the
Section found from that cleanup if it exists.

Differential Revision: https://reviews.llvm.org/D100850

Implements parts of:
    * P0896R4 The One Ranges Proposal

Depends on D99855.

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D99863

The previous check was wrong because it only checks that the LLVM CMake
directory exists. However, it's possible that the directory exists but
the `LLVMConfig.cmake` file does not. When this happens we would
incorectly try to include the non-existant file.

To fix this we make the check stricter by checking that the file
we want to include actually exists.

This is a follow up to fd28517d.

rdar://76870467

This reverts commit be20eae2.  It appears to have caused a crash on a buildbot (https://lab.llvm.org/buildbot#builders/77/builds/5653).  Reverting while investigating.

Adding the switches to reduce diffs.  I'm about to split that into an lshr part and an ashr part, doing the NFC part first makes it easier to maintain both diffs.

Add some specificity to libstdc++ hack, perhaps we can remove it at a
later date.

[InstCombine] Recognize `((x * y) s/ x) !=/== y` as an signed multiplication overflow check (PR48769)

We already had support for it's unsigned variant, so simply extend it
to also handle the signed variant.

Fixes https://bugs.llvm.org/show_bug.cgi?id=48769

We might as well test all of the codegen here.

An unfetched lazy symbol (undefined weak) should be considered to have its
original versionId which is VER_NDX_GLOBAL, instead of the lazy symbol's
versionId. (The original versionId cannot be non-VER_NDX_GLOBAL because a
undefined versioned symbol is an error.)

The regression was introduced in D77280 when making version scripts work
with lazy symbols fetched by LTO calls.

Fix PR49915

Differential Revision: https://reviews.llvm.org/D100624

Change cd ..\.. to cd llvm-project (the former is probably a leftover
of the old svn instructions)

Committer: Adrian McCarthy <amccarth@google.com>

Differential Revision: https://reviews.llvm.org/D68321

Currently, it is only possible to register an operation or a type
when the TypeID is defined at compile time. Same with InterfaceMaps
which can only be defined with compile-time defined interfaces.

With those changes, it is now possible to register types/operations
with custom TypeIDs. This is necessary to define new operations/types
at runtime.

Differential Revision: https://reviews.llvm.org/D99084

This extends the phi handling in isKnownNonEqual with a special case based on invertible recurrences. If we can prove the recurrence is invertible (which many common ones are), we can recurse through the start operands of the recurrence skipping the phi cycle.

(Side note: Instcombine currently does not push back through these cases. I will implement that in a follow up change w/separate review.)

Differential Revision: https://reviews.llvm.org/D99912

The debug mode tests for map/set's iterators construct empty
containers, making the code after the first increment meaningless.
It's never executed since the tests exit earlier.

It doesn't seem to be intentional, so the patch makes the tests
to construct containers that include at least one element.

Reviewed By: curdeius, Quuxplusone

Differential Revision: https://reviews.llvm.org/D100029

Looking at the Doxygen-generated documentation for the clang namespace
currently shows several random comments from different parts of the
codebase. These are caused by:

- File doc comments that aren't marked with \file, so they're attached to
  the next declaration, which is usually "namespace clang {".
- Class doc comments placed before the namespace rather than before the
  class.

This commit fixes these comments. The generated doxygen documentation now
has proper docs for several classes and files, and the docs for the clang
namespace is now empty.

Differential Revision: https://reviews.llvm.org/D96738

A couple of standard op examples that use an outdated syntax need an
update.

Differential Revision: https://reviews.llvm.org/D100840

The code example for "RecursiveASTVisitor based ASTFrontendActions"
was using unique_ptr<X>(new X) when creating the AST consumer; change
it to use make_unique instead. The main function of the same example
already used make_unique.

Differential Revision: https://reviews.llvm.org/D93185