[libc++] Properly pass the LNT submission token to the submit workflow (#233010)
Reusable worklows don't automatically get their environment secrets
passed, they need to declare them and their callers to pass them
explicitly.
[SLP] Handle REVEC when costing expanded compress mask
With REVEC the scalars are vectors. The masked-load-compress shuffle that is
emitted uses the compress mask expanded to the elements of those vectors
(transformScalarShuffleIndiciesToVector), but the cost was computed with the
unexpanded per-vector mask, so a shuffle such as <24 x i8> -> <16 x i8> was
costed as a <2 x i8> shuffle. This made the compress sequence looked cheaper
than it is.
Assisted-By: Claude Sonnet 5.5
[mlir] Check greedy rewrite fingerprints and changed flag (#232576)
Under EXPENSIVE_CHECKS, compare operation fingerprints before and after
greedy rewriting. If the IR changes but the driver reports no change,
emit a fatal error.
Assisted-by: gpt 6.1 sol
[InstCombine] Canonicalize atomicrmw sub of a constant to add
Rewrite `atomicrmw sub ptr, C` as `atomicrmw add ptr, -C`. This
matches the canonical form InstCombine already uses for plain `sub`.
In wrapping arithmetic $old - C = old + (-C)$, so both the stored
value and the returned old value stay the same, including when C is
`INT_MIN`. Ordering, syncscope and metadata are kept.
```llvm
; before
%old = atomicrmw sub ptr %p, i32 1 syncscope("agent") monotonic
; after
%old = atomicrmw add ptr %p, i32 -1 syncscope("agent") monotonic
```
This benefits AMDGPU, for example: https://godbolt.org/z/39xsYro3o
[CIR] Skip record rebuilds for unchanging types in CXXABI lowering (#232880)
CIRABITypeConverter only rewrites data-member and method types, but it
did not override typeMayChange, so every named record converted to a
renamed copy and every op touching one was illegal, forcing the generic
pattern to rebuild them all. Override it to report only those two types
as possibly changing, letting records that reach neither convert to
themselves and stay legal.
Small gains across the more expensive selfhosting TUs (no CIR output
changes):
- Registry 36.7->35.8,
- ASTImporterTest 64.4->63.7,
- SLPVectorizer 93.6->91.9,
- OpenMPDecomp 39.5->38.1,
- SemaExpr 59.3->57.5.
