DebugNamesDWARFIndex was jumping through hoops to construct a DIERef
from an index entry only to jump through them back a short while later
to construct a DWARFDIE.

This used to be necessary as the index lookup was a two stage process,
where we first enumerated all matches, and then examined them (so it was
important that the enumeration was cheap -- does not trigger unnecessary
parsing). However, now that the processing is callback based, we are
always immediately examining the DWARFDIE right after finding the entry,
and the DIERef just gets in the way.

While reassociating expressions, LICM is required to invalidate SCEV
results, as otherwise subsequent passes in the pipeline that leverage
LICM foldings (e.g. IndVars), may reason on invalid expressions; thus
miscompiling. This is achieved by rewriting the reassociable
instruction from scratch.

Fixes: https://github.com/llvm/llvm-project/issues/91957.

Using `for_` is very hand with python bindings. Currently, it doesn't
support results, we had to fallback to two lines scf.for.

This PR yields results of scf.for in `for_`

---------

Co-authored-by: Maksim Levental <maksim.levental@gmail.com>

Construct `Twine`s before concatenation.

Previously, we just check if the source is a virtual register and
this prevents some potential hoists.

We can see some improvements in AArch64/RISCV tests.

Amend 7c956293 ("MCAsmParser: Support
\+") to increase Macro.Count per iteration to match the new gas feature
(milestone: 2.43).

[C++20] [Modules] Don't generate the defintition for non-const available external variables (#93530)

Close https://github.com/llvm/llvm-project/issues/93497

The root cause of the problem is, we mark the variable from other
modules as constnant in LLVM incorrectly. This patch fixes this problem
by not emitting the defintition for non-const available external
variables. Since the non const available externally variable is not
helpful to the optimization.

This is a second attempt to land #84501 which failed on several targets.

This patch adds the HAS_IEE754_FLOAT128 define which makes the check for
typedef'ing float128 more precise by checking whether __uint128_t is
available and checking if the host does not use __ibm128 which is
prevalent on power pc targets and replaces IEEE754 float128s.

FP typed atomic load/store coverage was mostly missing, especially for
half and bfloat.

This patch takes Richard's approach of no longer modeling dependent NTTP
arguments with TemplateParamObjectDecls. Clang used to do so, which left
behind a problem in that we might mess up dependent and non-dependent
arguments that boil down to the same canonical type because there's a
default argument on the NTTP.

The problem of "canonical expression" is still present because this
patch doesn't touch the profiling part. Namely, #92292 seems different.

Fixes https://github.com/llvm/llvm-project/issues/84052

There's some code in AggExprEmitter::VisitCXXParenListOrInitListExpr to
try to do early cleanup for GEPs for fields that aren't accessed. But
it's unlikely to actually save significant compile-time, and it's subtly
wrong in cases where EmitLValueForFieldInitialization() doesn't create a
GEP. So just delete the code.

Fixes #88077. Fixes #89547.

Opcodes are the same for these instructions in GFX11 and 12,
hence this typo has no functional impact.

Reverts llvm/llvm-project#86223

windows pre-merge is broken.

Instead of using FOO_TEST_DEPS global variables that don't get updated
properly from subdirectories, use targets to propagate the dependencies
across directories.

A while back, the cxx_under_test Lit parameter was removed. This patch
reintroduces a Lit parameter called "compiler" which controls the value
of the %{cxx} substitution used in the test suite.

To run the test suite with a different compiler, one can now pass
--param compiler=<path>.

In essence, this header has always been related to configuration of
the library but we didn't want to put it inside <__config> due to
complexity reasons. Now that we have sub-headers in <__config>, we
can move <__availability> to it and stop including it everywhere since
we already obtain the required macros via <__config>.

This reverts commit 0380044e.

While I figure out some mysterious CMake error.

Since we have already addressed the LWG issue, this PR marks LWG3951 as
implemented.

Signed-off-by: yronglin <yronglin777@gmail.com>
Co-authored-by: A. Jiang <de34@live.cn>

The DominatorTree can be reused if no CFG changes.

There was a Darwin only use of setupterm (under USE_SETUPTERM_WORKAROUND)
that required libcurses.dylib.  That was added to the main build, but
not to the unittest.

Without this change, the build will fail like so:

llvm-project/lld/MachO/ObjC.cpp:1387:75: error: ISO C++20 considers use of overloaded operator '==' (with operand types 'ObjcCategoryMerger::PointerListInfo' and 'ObjcCategoryMerger::PointerListInfo') to be ambiguous despite there being a unique best viable function [-Werror,-Wambiguous-reversed-operator]
 1387 |       parseProtocolListInfo(classIsec, roClassLayout.baseProtocolsOffset) ==
      |       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^
 1388 |           parseProtocolListInfo(metaIsec, roClassLayout.baseProtocolsOffset) &&
      |           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/assert.h:100:27: note: expanded from macro 'assert'
  100 |      (static_cast <bool> (expr)                                         \
      |                           ^~~~
llvm-project/lld/MachO/ObjC.cpp:391:17: note: ambiguity is between a regular...

Tighten the verifier for arith cast ops to disallow changing tensor
dimensions, e.g., static to dynamic. After this change:
* `arith.cast_op %x : tensor<4xi32> to tensor<4xf32>` remains valid
* `arith.cast_op %x : tensor<4xi32> to tensor<?xf32>` becomes invalid
* `arith.cast_op %x : tensor<?xi32> to tensor<4xf32>` becomes invalid

This is mostly to simplify the op semantics. See the discussion thread
for more context:
https://discourse.llvm.org/t/rfc-remove-arith-math-ops-on-tensors/74357/63.

Testing github actions is such a pain. I swear it should match now.

This was added in #93586 but caused a compilation warning and is not
used anyway.

This defines a new kind of IR Constant that represents a ptrauth signed
pointer, as used in AArch64 PAuth.

It allows representing most kinds of signed pointer constants used thus
far in the llvm ptrauth implementations, notably those used in the
Darwin and ELF ABIs being implemented for c/c++.  These signed pointer
constants are then lowered to ELF/MachO relocations.

These can be simply thought of as a constant `llvm.ptrauth.sign`, with
the interesting addition of discriminator computation: the `ptrauth`
constant can also represent a combined blend, when both address and
integer discriminator operands are used.  Both operands are otherwise
optional, with default values 0/null.

This reuses most of the code that was created for f32x4 and f64x2 binary
instructions and tries to follow how they were implemented.

add/sub/mul/div - use regular LL instructions
min/max - use the minimum/maximum intrinsic, and also have builtins
pmin/pmax - use the wasm.pmax/pmin intrinsics and also have builtins

Specified at:

https://github.com/WebAssembly/half-precision/blob/29a9b9462c9285d4ccc1a5dc39214ddfd1892658/proposals/half-precision/Overview.md

This adds `-wasm-enable-exnref`, which will enable the new EH
instructions using `exnref` (adopted in Oct 2023 CG meeting):
https://github.com/WebAssembly/exception-handling/blob/main/proposals/exception-handling/Exceptions.md
This option should be used with `-wasm-enable-eh`.

This patch adds a predicated version of
getSymbolicMaxBackedgeTakenCount.

The intended use for this is loop access analysis for loops with
uncountable exits. When analyzing dependences and computing runtime
checks, we need the smallest upper bound on the number of iterations. In
terms of memory safety, it shouldn't matter if any uncomputable exits
leave the loop, as long as we prove that there are no dependences given
the minimum of the countable exits. The same should apply also for
generating runtime checks.

PR: https://github.com/llvm/llvm-project/pull/93498

This is the continuation of
https://github.com/llvm/llvm-project/pull/88674

.

Fixes #88433, #90496.

---------

Co-authored-by: aniplcc <aniplccode@gmail.com>

This adds (back) the exnref type restored in the new EH proposal adopted
in Oct 2023 CG meeting:

https://github.com/WebAssembly/exception-handling/blob/main/proposals/exception-handling/Exceptions.md:x

[RISCV] Combine vXi32 (mul (and (lshr X, 15), 0x10001), 0xffff) -> (bitcast (sra (v2Xi16 (bitcast X)), 15)) (#93565)

Similar for i16 and i64 elements for both fixed and scalable vectors.

This reduces the number of vector instructions, but increases vl/vtype
toggles.

This reduces some code in 525.x264_r from SPEC2017. In that usage, the
vectors are fixed with a small number of elements so vsetivli can be
used.

This is similar to `performMulVectorCmpZeroCombine` from AArch64.

We are using PLTs for cortex-m33 which only supports thumb. More
specifically, this is for a very restricted use case. There's no MMU so
there's no sharing of virtual addresses between two processes, but this
is fine. The MCU is used for running [chre
nanoapps](https://android.googlesource.com/platform/system/chre/+/HEAD/doc/nanoapp_overview.md)
for android. Each nanoapp is a shared library (but effectively acts as
an executable containing a test suite) that is loaded and run on the MCU
one binary at a time and there's only one process running at a time, so
we ensure that the same text segment cannot be shared by two different
running executables. GNU LD supports thumb PLTs but we want to migrate
to a clang toolchain and use LLD, so thumb PLTs are needed.