All supported compilers support the -std=year except Clang < 17 which
doesn't support C++23. This fallback is marked for removal once we no
longer support Clang 16.

Reviewed By: #libc, ldionne

Differential Revision: https://reviews.llvm.org/D152106

The mask used to check whether a code unit is a valid continuation was
incorrect and accepts non-continuation code points. This fixes the
issue.

Reviewed By: ldionne, tahonermann, #libc

Differential Revision: https://reviews.llvm.org/D149672

This version allowed testing the std module in C++26 mode.

Reviewed By: #libc, ldionne

Differential Revision: https://reviews.llvm.org/D153227

{mini|maxi}mum intrinsics are different from {min|max}num intrinsics in
the propagation of NaN and signed zero. Also, the minnum/maxnum
intrinsics require the presence of nsz flags to be valid reductions in
vectorizer. In this regard, we introduce a new recurrence kind and also
add support for identifying reduction patterns using these intrinsics.

The reduction intrinsics and lowering was introduced here: 26bfbec5.

There are tests added which show how this interacts across chains of
min/max patterns.

Differential Revision: https://reviews.llvm.org/D151482

2700da5f added lld/test/Unit/lit.site.cfg.py.in in a state
that half-supports relocatable lld lit tests.

Make them fully relocatable.

See description of fb80b6b2 for background.

Differential Revision: https://reviews.llvm.org/D152885

The optimizing, non-broken features have all been moved to
AMDGPUAttributor. The only remaining piece of functionality was the
broken propagation of the wavesize features. This was fundamentally
broken and a hack for device library linking. It doesn't matter when
the device libraries are correctly linked and internalized.

In case of linked-as-normal-bitcode (as comgr still does), we're
reliant on the global subtarget anyway. If we can get away without
forcing target-cpu, we should just as well be able to get away without
propagating target-features.

This patch adds support for the TLS local-exec access model on AIX to allow
for the ability to generate the 32-bit (specifically, non-optimized) code sequence.
This work is a follow up of D149722.

The particular sequence that is generated for this sequence is as follows:
```
.tc var[TC],var[TL]@le.   // variable offset, with the le relocation specifier

bla .__get_tpointer()     // get the thread pointer, modifies r3
lwz reg1, var[TC](2)      // load the variable offset
add reg2, r3, reg1        // add the variable offset to the retrieved thread pointer
```

Differential Revision: https://reviews.llvm.org/D152669

Unless I'm missing something we need to update the whole vector
not just where OddMask is true.

Reviewed By: luke

Differential Revision: https://reviews.llvm.org/D153087

This reverts commit 8cf89568.

This was looking for full copies produced by SplitKit, but SplitKit
introduces copy bundles if not all lanes are live. The scan for uses
needs to look at bundles, not individual instructions.

This is a prerequisite to avoiding some redundant spills due to
subregisters which will help avoid an allocation failure in a future
patch.

This patch renames load/store enums to be equivalent
to the contiguous addressing modes with _STRIDED and _STRIDED_IMM
suffixed.

Also, reformat all clang-format related files.

Differential Revision: https://reviews.llvm.org/D153208

Otherwise, Clang complains about format_ctx being unused in the tests
when exceptions are disabled in Freestanding mode. I don't know why it
doesn't complain not in freestanding mode.

Differential Revision: https://reviews.llvm.org/D153301

Changes to preconditions have no impact on the library.

Implements
- LWG3927 Unclear preconditions for operator[] for sequence containers

Reviewed By: #libc, philnik

Differential Revision: https://reviews.llvm.org/D153286

Note libc++ implemented this in its initial version.

Implements
- LWG3935 template<class X> constexpr complex& operator=(const complex<X>&) has no specification

Reviewed By: #libc, philnik, ldionne

Differential Revision: https://reviews.llvm.org/D153287

Wrap the getSExtOrTrunc/getZExtOrTrunc calls behind an IsSigned argument.

Commit the bitcode file instead of generating it dynamically, as
this will no longer be possible in the future.

This fixes rdar://110330781, which asked for the feature-test macro
for std::pmr to take into account the deployment target. It doesn't
fix https://llvm.org/PR62212, though, because the availability markup
itself must be disabled until some Clang bugs have been fixed.

This is pretty vexing, however at least everything should work once
those Clang bugs have been fixed. In the meantime, this patch at least
adds the required markup (as disabled) and ensures that the feature-test
macro for std::pmr is aware of the deployment target requirement.

Differential Revision: https://reviews.llvm.org/D135813

These tests were testing both typed an opaque pointers. Only keep
opaque pointers tests.

Commit the typed pointer bitcode file instead of producing it,
as this will not be possible in the future anymore.

This is a generic DAG combine version of D151055 which recognizes when a signed ABDS can be safely replaced with a unsigned ABDU instruction if it is legal.

Alive2: https://alive2.llvm.org/ce/z/pb5BjG

Differential Revision: https://reviews.llvm.org/D153328

Add tablegen pattern for uaddlv(uaddlp(x)) ==> uaddlv(x).

Differential Revision: https://reviews.llvm.org/D153323

Differential Revision: https://reviews.llvm.org/D153322

This patch optimizes code generation by leveraging the zeroing behavior of the `maskeqz`/`masknez` instructions.

```
int sel(int a, int b)
{
    return (a < b) ? a : 0;
}
```

```
slt	$a1,$a0,$a1
masknez	$a2,$r0,$a1
maskeqz	$a0,$a0,$a1
or	$a0,$a0,$a2
```

=>

```
slt	$a1,$a0,$a1
maskeqz	$a0,$a0,$a1
```

Reviewed By: SixWeining

Differential Revision: https://reviews.llvm.org/D153193

Verifying dominator tree is expensive using intra-pass
asserts. Asserts added during D147408 are
increasing the build time of libc significantly. This change
does the verification after the atomic optimizer pass
and should fix the regression reported in D153232.

Reviewed By: arsenm, #amdgpu

Differential Revision: https://reviews.llvm.org/D153261

Re-organize special cases and add a special case when `|x| < 2^-5`.

Reviewed By: michaelrj

Differential Revision: https://reviews.llvm.org/D153134

Re-order exceptional branches and slightly adjust the evaluation.
Depends on https://reviews.llvm.org/D153026 .

Reviewed By: michaelrj

Differential Revision: https://reviews.llvm.org/D153062

Re-order exceptional branches and slightly adjust the evaluation.

Performance tested with the CORE-MATH project on AMD EPYC 7B12 (clocks/op)

Reciprocal throughputs:
```
--- BEFORE ---

$ CORE_MATH_PERF_MODE=rdtsc ./perf.sh tanhf
[####################] 100 %  (with -mavx2 -mfma)
Ntrial = 20 ; Min = 7.794 + 0.102 clc/call; Median-Min = 0.066 clc/call; Max = 8.267 clc/call;
[####################] 100 %. (with -msse4.2)
Ntrial = 20 ; Min = 10.783 + 0.172 clc/call; Median-Min = 0.144 clc/call; Max = 11.446 clc/call;
[####################] 100 %. (SSE2)
Ntrial = 20 ; Min = 18.926 + 0.381 clc/call; Median-Min = 0.342 clc/call; Max = 19.623 clc/call;

--- AFTER ---

$ CORE_MATH_PERF_MODE=rdtsc ./perf.sh tanhf
[####################] 100 %  (with -mavx2 -mfma)
Ntrial = 20 ; Min = 6.598 + 0.085 clc/call; Median-Min = 0.052 clc/call; Max = 6.868 clc/call;
[####################] 100 %  (with -msse4.2)
Ntrial = 20 ; Min = 9.245 + 0.304 clc/call; Median-Min = 0.248 clc/call; Max = 10.675 clc/call;
[####################] 100 %. (SSE2)
Ntrial = 20 ; Min = 11.724 + 0.440 clc/call; Median-Min = 0.444 clc/call; Max = 12.262 clc/call;
```

Latency:
```
--- BEFORE ---

$ PERF_ARGS="--latency" CORE_MATH_PERF_MODE=rdtsc ./perf.sh tanhf
[####################] 100 %  (with -mavx2 -mfma)
Ntrial = 20 ; Min = 38.821 + 0.157 clc/call; Median-Min = 0.122 clc/call; Max = 39.539 clc/call;
[####################] 100 %. (with -msse4.2)
Ntrial = 20 ; Min = 44.767 + 0.766 clc/call; Median-Min = 0.681 clc/call; Max = 45.951 clc/call;
[####################] 100 %. (SSE2)
Ntrial = 20 ; Min = 55.055 + 1.512 clc/call; Median-Min = 1.571 clc/call; Max = 57.039 clc/call;

--- AFTER ---

$ PERF_ARGS="--latency" CORE_MATH_PERF_MODE=rdtsc ./perf.sh tanhf
[####################] 100 %  (with -mavx2 -mfma)
Ntrial = 20 ; Min = 36.147 + 0.194 clc/call; Median-Min = 0.181 clc/call; Max = 36.536 clc/call;
[####################] 100 %  (with -msse4.2)
Ntrial = 20 ; Min = 40.904 + 0.728 clc/call; Median-Min = 0.557 clc/call; Max = 42.231 clc/call;
[####################] 100 %. (SSE2)
Ntrial = 20 ; Min = 55.776 + 0.557 clc/call; Median-Min = 0.542 clc/call; Max = 56.551 clc/call;
```

Reviewed By: michaelrj

Differential Revision: https://reviews.llvm.org/D153026

[LoongArch] Add missing chains and remove unnecessary `SDNPSideEffect` property for some intrinsic nodes

Similar to the existing f32 pattern, this adds a tablegen pattern for the fp16
fcvtn2.