A "BTI c" instruction only allows jumping/calling to using a BLR* instruction.
However, the SLSBLR mitigation changes a BLR to a BR to implement the
function call. Therefore, a "BTI c" check that passed before could
trigger after the BLR->BL change done by the SLSBLR mitigation.
However, if the register used in BR is X16 or X17, this trigger will not
fire (see ArmARM for further details).

Therefore, this patch simply changes the function stubs for the SLSBLR
mitigation from
__llvm_slsblr_thunk_x<N>:
    br x<N>
    SpeculationBarrier
to
__llvm_slsblr_thunk_x<N>:
    mov x16, x<N>
    br  x16
    SpeculationBarrier

Differential Revision: https://reviews.llvm.org/D81405

Summary: This allows targets to also consider the symbol's type and/or address if needed.

Reviewers: scott.linder, jhenderson, MaskRay, aardappel

Reviewed By: scott.linder, MaskRay

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, aheejin, rupprecht, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82090

Reviewers: efriedma, sdesmalen

Reviewed By: efriedma

Subscribers: tschuett, hiraditya, rkruppe, psnobl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80741

We currently miss a number of opportunities to emit single-instruction
VMRG[LH][BHW] instructions for shuffles on little endian subtargets. Although
this in itself is not a huge performance opportunity since loading the permute
vector for a VPERM can always be pulled out of loops, producing such merge
instructions is useful to downstream optimizations.
Since VPERM is essentially opaque to all subsequent optimizations, we want to
avoid it as much as possible. Other permute instructions have semantics that can
be reasoned about much more easily in later optimizations.

This patch does the following:
- Canonicalize shuffles so that the first element comes from the first vector
  (since that's what most of the mask matching functions want)
- Switch the elements that come from splat vectors so that they match the
  corresponding elements from the other vector (to allow for merges)
- Adds debugging messages for when a shuffle is matched to a VPERM so that
  anyone interested in improving this further can get the info for their code

Differential revision: https://reviews.llvm.org/D77448

Add code to respect mad-mac-f32-insts target feature.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D81990

Summary: so it doesn't change the C ABI

Reviewers: deadalnix

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82135

Emscripten has emulations for several headers found on Linux,
including spwan.h and endian.h

Differential Revision: https://reviews.llvm.org/D82121

Summary:
Extend StackLifetime with option to calculate liveliness
where alloca is only considered alive on basic block entry
if all non-dead predecessors had it alive at terminators.

Depends on D82043.

Reviewers: eugenis

Reviewed By: eugenis

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82124

Summary: lifetime.ll is a copy of SafeStack/X86/coloring2.ll

Reviewers: eugenis

Reviewed By: eugenis

Subscribers: hiraditya, mgrang, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82043

Don't do this in the MachineFunctionInfo constructor. Also, ensure the
alignment rather than overwriting it outright. I vaguely remember
there was another place to enforce the target minimum alignment, but I
couldn't find it (it's there for instructions).

We probably need to move where intrinsics are lowered to copies to
make this useful.

Private pointers used to workaround IR semantics by artifically
reserving an object at offset 0 so no user object would be allocated
there. Since alloca now uses a non-0 address space, that workaround is
unnecssary and 0 can be treated as a valid pointer.

I don't know anything about debug info, but this seems like more work
should be necessary. This constructs a new IRBuilder and reconstructs
the original divides rather than moving the original.

One problem this has is if a div/rem pair are handled, both end up
with the same debugloc. I'm not sure how to fix this, since this uses
a cache when it sees the same input operands again, which will have
the first instance's location attached.

This patch implements builtins for the following prototypes:

vector unsigned long long vec_pdep(vector unsigned long long, vector unsigned long long);
vector unsigned long long vec_pext(vector unsigned long long, vector unsigned long long __b);
unsigned long long __builtin_pdepd (unsigned long long, unsigned long long);
unsigned long long __builtin_pextd (unsigned long long, unsigned long long);

Revision Depends on D80758

Differential Revision: https://reviews.llvm.org/D80935

In one case, UpdateDefs was not getting set and a dead SmallVector
constructed. In another, it was adding new vreg defs to the updated
set which should be unnecessary. This also wasn't considering the
multiple defs of G_UNMERGE_VALUES.

Also increase the small vector sizes for merge/unmerge operands to the
usual semi-arbitrary 8. While debugging these, I'm usually seeing
merges and unmerges with at least 4 uses/defs.

I haven't run into an actual problem from any of these though.

This was passing in all the parameters needed to construct a
LegalizerHelper in the custom legalization, when it's simpler to just
pass in the existing helper.

This is slightly more annoying to use in the common case where you
don't need the legalizer helper, but we could add back the common
parameters back in addition to the helper.

I didn't propagate this to all the internal target changes that this
logically implies, but did update a sample one for
legalizeMinNumMaxNum.

This is in preparation for moving AMDGPU load/store legalization
entirely into custom lowering. The current set of legalization actions
is really constraining and not really capable of expressing all the
actions needed to legalize loads/stores. In particular there's no way
to express when the memory access itself needs to change size vs. the
result type. There's also a lot of redundancy since the same
split/widen actions need to be applied in both vector and scalar
cases. All of the sub-cases logically belong as steps in the legalizer
helper, but it will be easier to consider everything at once in custom
lowering.

Summary:
Restructure HowToUpdateDebugInfo.rst to specify rules for when
transformations should preserve, merge, or drop debug locations.

The goal is to have clear, well-justified rules that come with a few
examples and counter-examples, so that pass authors can pick the best
strategy for managing debug locations depending on the specific task at
hand.

I've tried to set down sensible rules here that mostly align with what
we already do in llvm today, and that take a diverse set of use cases
into account (interactive debugging, crash triage, SamplePGO).

Please *do* try to pick these rules apart and suggest clarifications or
improvements :).

Side note: Prior to 24660ea1, this document was structured as a long
list of very specific code transformations -- the idea being that we
would fill in what to do in each specific case. I chose to reorganize
the document as a list of actions to take because it drastically cuts
down on the amount of redundant exposition/explanation needed. I hope
that's fine...

Reviewers: jmorse, aprantl, dblaikie

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D81198

Update the Sphinx configuration for the removal of source_parsers in
Sphinx 3.0. The variable has been deprecated since version 1.8.

> Version 1.8 deprecates and version 3.0 removes the source_parsers
> configuration variable that was used by older recommonmark versions.

https://www.sphinx-doc.org/en/master/usage/markdown.html

Differential revision: https://reviews.llvm.org/D75284

[AIX] Split lit test shtest-format into two separate tests and add AIX as UNSUPPORTED for shtest-format-argv0

Summary: lit test `shtest-format.py` fails on AIX  because one of the subtest of shtest-format requires the tool `[` to be installed under the system PATH. For AIX, `[` is only available as a shell builtin and does not present as an executable file under PATH. Hence, split the original shtest-format into two separate test files and added AIX as UNSUPPORTED for the test using `[` .

Reviewers: daltenty, hubert.reinterpretcast

Reviewed By: hubert.reinterpretcast

Subscribers: delcypher, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82100

Reviewers: efriedma, c-rhodes, david-arm, Tyker, asbirlea

Reviewed By: david-arm

Subscribers: tschuett, hiraditya, rkruppe, psnobl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82057

[CodeView] Revert 8374bf43 and 403f9537

This reverts:
8374bf43 [CodeView] Fix generated command-line expansion in LF_BUILDINFO. Fix the 'pdb' entry which was previously a null reference, now an empty string.
403f9537 [CodeView] Add full repro to LF_BUILDINFO record

This is causing the lld/test/COFF/pdb-relative-source-lines.test to fail: http://lab.llvm.org:8011/builders/lld-x86_64-win/builds/1096/steps/test-check-all/logs/FAIL%3A%20lld%3A%3Apdb-relative-source-lines.test
And clang/test/CodeGen/debug-info-codeview-buildinfo.c fails as well: http://lab.llvm.org:8011/builders/clang-s390x-linux/builds/33346/steps/ninja%20check%201/logs/FAIL%3A%20Clang%3A%3Adebug-info-codeview-buildinfo.c

This functionality is very similar to Function compatibility with
AnnotationWriter. This change allows us to use AnnotationWriter with
BasicBlock through BB.print() method.

Reviewed-By: apilipenko
Differntial Revision: https://reviews.llvm.org/D81321

The predicate can always be used to distinguish between icmp and fcmp,
so we don't need to keep repeating this check in the callers.

This should probably be implied for all the speculatable ones. I think
the only ones where this plausibly doesn't apply is s_sendmsghalt and
maybe kill.

Sometimes a dead block gets folded and the debug information is still
retained. This manifests as jumpy stepping in lldb, see the bugzilla PR
for an end-to-end C testcase.

Fixes https://bugs.llvm.org/show_bug.cgi?id=46008

Differential Revision:  https://reviews.llvm.org/D82062

Reviewers: arsenm

Subscribers: wdng, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82025

Move code that may update the IR after precondition, so that if precondition
fail, the IR isn't modified.

Differential Revision: https://reviews.llvm.org/D81225

These don't really modify any memory, and should not expect memory
operands.

Nothing breaks yet, but all encodings shall be in the map.

Differential Revision: https://reviews.llvm.org/D81974

Previously the script only handled C input, this change extends the JSON
parsing to to also include C++ function types such as methods, constructors
and destructors.

Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D80914

Function declarations can in fact have an 'inner' node that lists the
ParmVarDecls. It seems like either the JSON output has changed or that I
tested the original JSON parsing change with test files that only have
function definitions without arguments.

Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D80913

Highlight the `bfloat` type introduced in D78190.

When possible (e.g. internal linkage), strip preallocated attribute off
parameters/arguments.
This requires removing the "preallocated" operand bundle from the call
site, replacing @llvm.call.preallocated.arg() with an alloca and a
bitcast to i8*, and removing the @llvm.call.preallocated.setup(). Since
@llvm.call.preallocated.arg() can be called multiple times with the same
arg index, we create an alloca per arg index.
We add a @llvm.stacksave() where the @llvm.call.preallocated.setup() was
and a @llvm.stackrestore() after the preallocated call to prevent the
stack from blowing up. This is valid because the argument would normally
not exist on the stack after the call before the transformation.

This does not currently handle all possible preallocated calls. We will
need to figure out where to put @llvm.stackrestore() in the cases where
there is no obvious place to put it, for example conditional
preallocated calls, invokes.

This sort of transformation may need to be moved to somewhere more
accessible to accomodate similar transformations (like inlining) in the
future.

Reviewers: efriedma, hans

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80951

https://bugs.llvm.org/show_bug.cgi?id=45360

This is reduced from the (runnable) test provided in the bug report.
The remainder operation is originally guarded, it never divides by zero.
Indvars should not make it execute unconditionally.

This is not a great test, running whole -O2 is fragile,
but i really don't understand why running -indvars on the IR before
that tranform happens doesn't work.

This patch adds basic support for BFloat in the Arm backend.
For now the code generation relies on fullfp16 being present.

Briefly:
* adds the bfloat scalar and vector types in the necessary register classes,
* adjusts the calling convention to cope with bfloat argument passing and return,
* adds codegen patterns for moves, loads and stores.

It's tested mostly by the intrinsic patches that depend on it (load/store, convert/copy).

The following people contributed to this patch:

 * Alexandros Lamprineas
 * Ties Stuij

Differential Revision: https://reviews.llvm.org/D81373

Differential Revision: https://reviews.llvm.org/D82034

[TargetLowering] SimplifyMultipleUseDemandedBits - drop already extended ISD::SIGN_EXTEND_INREG nodes.

If the source of the SIGN_EXTEND_INREG node is already sign extended, use the source directly.