Folding a `select` into a floating point binary operators can only be
done if the result is preserved for both case. In particular, if the
other operand of the `select` can be a NaN, then the transformation
won't preserve the result value.

GNU readelf prints a blank line before the first hex/string dump, which
serves as a separator when there are other dump operations. Port the
behavior.

Pull Request: https://github.com/llvm/llvm-project/pull/85744

This adds a reduced test case for the regression seen in x264 with #83035.
If the intermediate concatenating shuffles are large enough then the
splitting combine will prevent the strided load combine which is
preferable.

These are the last remaining "trivial" changes to passes that use
Instruction pointers for insertion. All of this should be NFC, it's just
changing the spelling of how we identify a position.

In one or two locations, I'm also switching uses of getNextNode etc to
using std::next with iterators. This too should be NFC.

---------

Merged by: Stephen Tozer <stephen.tozer@sony.com>

Towards the goal of implementing __cxa_finalize (#85651) I'd like to be able to
reverse iterate over cpp::arrays such as the one used in FixedVector.

Implement the enough iterator support to be able to iterate a cpp::array in
reverse, and add tests.

Of note, reverse iterator's begin() refers to forward iterator's end() (and
vice versa). When dereferenced (operator*), the reverse iterator returns a copy
that's been pre-decremented (the underlying forward iterator is advanced).

This commit ensures that SROA does no longer attempt to split allocas
that are indexed into dynamically. Dynamic indices into arrays are
allowed to be negative or out-of-bounds, when the alloca containing the
array has memory backing these produced indices.

this implements part 1 of 2 for #83626
- `CGBuiltin.cpp` - modified to have seperate cases for signed and
unsigned integers.
- `SemaChecking.cpp` - modified to prevent the generation of a double
dot product intrinsic if the builtin were to be called directly.
- `IntrinsicsDirectX.td` creation of the signed and unsigned dot
intrinsics needed for instruction expansion.
- `DXILIntrinsicExpansion.cpp` - handle instruction expansion cases for
integer dot product.

This is part of a series of small patches to compute shuffle masks for
the couple of cases where we call getShuffleCost without one. My goal is
to add an invariant that all calls to getShuffleCost for fixed length
vectors have a mask.

Note that this code appears to be reachable with scalable vectors, and
thus we have to only pass a non-empty mask when the number of elements
is precisely known.

PR adds `nvvm.barrier.arrive` Op. It is useful op for producer consumer
modeling.

Fixes a build error caused by an unupdated getAsInstruction callsite in clang.

This reverts commit ab851f7f.

SSE only has AVGCEILU vXi8/vXi16 support - but for other types we should be trying to use the fixed width expansion instead of extensions

Remove support for obfuscated bitcode in dsymutil and the DWARF linker.
We no longer support bitcode submissions and the obfuscation support has
been removed from the rest of the compiler.

rdar://123863918

This improves overall analysis for minbitwidth in SLP. It allows to
analyze the trees with store/insertelement root nodes. Also, instead of
using single minbitwidth, detected from the very first analysis stage,
it tries to detect the best one for each trunc/ext subtree in the graph
and use it for the subtree.
Results in better code and less vector register pressure.

Metric: size..text

Program                                                                                                                                                size..text
                                                                                                                                                       results     results0    diff
                                                                      test-suite :: SingleSource/Benchmarks/Adobe-C++/simple_types_loop_invariant.test    92549.00    92609.00  0.1%
                                                                                  test-suite :: External/SPEC/CINT2017speed/625.x264_s/625.x264_s.test   663381.00   663493.00  0.0%
                                                                                   test-suite :: External/SPEC/CINT2017rate/525.x264_r/525.x264_r.test   663381.00   663493.00  0.0%
                                                                                               test-suite :: MultiSource/Benchmarks/Bullet/bullet.test   307182.00   307214.00  0.0%
                                                                             test-suite :: External/SPEC/CFP2017speed/638.imagick_s/638.imagick_s.test  1394420.00  1394484.00  0.0%
                                                                              test-suite :: External/SPEC/CFP2017rate/538.imagick_r/538.imagick_r.test  1394420.00  1394484.00  0.0%
                                                                                test-suite :: External/SPEC/CFP2017rate/510.parest_r/510.parest_r.test  2040257.00  2040273.00  0.0%

                                                                              test-suite :: External/SPEC/CFP2017rate/526.blender_r/526.blender_r.test 12396098.00 12395858.00 -0.0%
                                                                                         test-suite :: External/SPEC/CINT2006/445.gobmk/445.gobmk.test   909944.00   909768.00 -0.0%

SingleSource/Benchmarks/Adobe-C++/simple_types_loop_invariant - 4 scalar
instructions remain scalar (good).
Spec2017/x264 - the whole function idct4x4dc is vectorized using <16
x i16> instead of <16 x i32>, also zext/trunc are removed. In other
places last vector zext/sext removed and replaced by
extractelement + scalar zext/sext pair.
MultiSource/Benchmarks/Bullet/bullet - reduce or <4 x i32> replaced by
reduce or <4 x i8>
Spec2017/imagick - Removed extra zext from 2 packs of the operations.
Spec2017/parest - Removed extra zext, replaced by extractelement+scalar
zext
Spec2017/blender - the whole bunch of vector zext/sext replaced by
extractelement+scalar zext/sext, some extra code vectorized in smaller
types.
Spec2006/gobmk - fixed cost estimation, some small code remains scalar.

Original Pull Request: https://github.com/llvm/llvm-project/pull/84334

The patch has the same functionality (no test changes, no changes in
benchmarks) as the original patch, just has some compile time
improvements + fixes for xxhash unittest, discovered earlier in the
previous version of the patch.

Reviewers:

Pull Request: https://github.com/llvm/llvm-project/pull/84536

All the isKnownNonZero() handling for instructions should be inside
this function. This makes the structure more similar to
computeKnownBitsFromOperator() as well.

This may not be entirely NFC due to different depth handling.

gcc bot failures with `atanf(+-Inf)`:
https://lab.llvm.org/buildbot/#/builders/250/builds/20331/steps/8/logs/stdio

Move the declaration of the Ty variable outside the NDEBUG guard
and make use of it in the remainder of the function.

Predefined macro FUNCTION in clang is not returning the same string than
MS for templated functions.

See https://godbolt.org/z/q3EKn5zq4

For the same test case MSVC is returning:

function: TestClass::TestClass
function: TestStruct::TestStruct
function: TestEnum::TestEnum

The initial work for this was in the reverted patch
(https://github.com/llvm/llvm-project/pull/66120). This patch solves the
issues raised in the reverted patch.

Nowadays !range can be placed on instructions with vector of int
return value. Support this case in isKnownNonZero().

`macho-relative-method-lists.test` is failing on little endian
platforms, when matching 'name'.

```
CHK32-NEXT: name 0x144 (0x{{[0-9a-f]*}}) instance_method_00

next:10'0             X error: no match found
          18:  name 0x144 (0x7ac)      
```
This seems like the obvious fix.

Co-authored-by: Alex B <alexborcan@meta.com>

Reverted due to buildbot failures:
https://lab.llvm.org/buildbot/#/builders/139/builds/61717/

This reverts commit 7ef433f6.

This commit was mistakenly reverted in place of the actual failing
commit prior; reapplying.

This reverts commit db4170a4.

Reverted due to buildbot failures:
https://lab.llvm.org/buildbot/#/builders/139/builds/61717/

This reverts commit b4b7d988.

On Darwin, -isysroot is needed and is automatically appended to
%flang and %flang_fc1, so use %flang_fc1 instead to have both -fc1
and -isysroot in the expected positions and avoid errors.

Because the RemoveDIs work is putting a debug-info bit into
BasicBlock::iterator and iterators are needed for insertion, the
getAsInstruction method declaration would need to use a fully defined
instruction-iterator, which leads to a complicated
header-inclusion-order problem. Much simpler to instead just not insert,
and make it the callers problem to insert.

This is proportionate because there are only four call-sites to
getAsInstruction -- it would suck if we did this everywhere.

---------

Merged by: Stephen Tozer <stephen.tozer@sony.com>

This is re-working of #74460, which adds a soft-float ABI for AArch64.
That was reverted because it causes errors when building the linux and
fuchsia kernels.

The problem is that GCC's implementation of the ABI compatibility checks
when using the hard-float ABI on a target without FP registers does it's
checks after optimisation. The previous version of this patch reported
errors for all uses of floating-point types, which is stricter than what
GCC does in practice.

This changes two things compared to the first version:
* Only check the types of function arguments and returns, not the types
of other values. This is more relaxed than GCC, while still guaranteeing
ABI compatibility.
* Move the check from Sema to CodeGen, so that inline functions are only
checked if they are actually used. There are some cases in the linux
kernel which depend on this behaviour of GCC.

The baseline version calculations was assuming the minor release would
always be 0.

This patch vastly simplifies the code handling terminators, without
changing any
behavior. Additionally, the simplification unblocks our ability to
address a
(simple) FIXME in the code to invoke `transferBranch`, even when builtin
options
are disabled.

Seeing how constant-hoisting also happens to store an insertion-point in
a DenseMap, this means we have to install DenseMapInfo for hashing
BasicBlock::iterators and comparing them. I'm not really sure where to
put the DenseMapInfo declarations as BasicBlock.h seems most logical,
but that then means including DenseMap.h into pretty much all of LLVM.
I've sent this up to the compile time tracker to see whether there's a
major cost from this.

---------

Merged by: Stephen Tozer <stephen.tozer@sony.com>

If --load-bitcode-into-experimental-debuginfo-iterators is true then debug
intrinsics are auto-upgraded to DbgRecords (the new debug info format).

The upgrade is trivial because the two representations are semantically
identical. llvm.dbg.value with 4 operands and llvm.dbg.addr intrinsics are
upgraded in the same way as usual, but converted directly into DbgRecords
instead of debug intrinsics.

Instead of hardcoding a specific IRBuilder type, use the base
class.

Revert "[Flang][OpenMP][Lower] NFC: Move clause processing helpers into the ClauseProcessor (#85258)"

Reverting due to failing gfortran test.

This reverts commit 2f2f16f3.

Fixing the type of the constant to avoid undefined behavior with respect
to overflow.

The checker alpha.security.ArrayBoundV2 performs bounds checking in two
steps: first it checks for underflow, and if it isn't guaranteed then it
assumes that there is no underflow. After this, it checks for overflow,
and if that's guaranteed or the index is tainted then it reports it.

This meant that in situations where overflow and underflow are both
possible (but the index is either tainted or guaranteed to be invalid),
the checker was reporting just an overflow error.

This commit modifies the messages printed in these cases to mention the
possibility of an underflow.

---------

Co-authored-by: Balazs Benics <benicsbalazs@gmail.com>