[LoopIdiom] Use narrower bit widths where possible in `optimizeCRCLoopUsingClmul` (#210139)
The original implementation of `optimizeCRCLoopUsingClmul` (#203405)
uses a single conservative bit width for most operations, but this width
is not always necessary. Use more restrictive bit widths for each clmul
according to their inputs, and narrow the bit width for the initial
CRC/data setup.
[X86] Fix swapped VPTERNLOG231_imm8/VPTERNLOG312_imm8 SDNodeXForm bodies (#209782)
Fixes #157929
VPTERNLOG231_imm8 and VPTERNLOG312_imm8 had their bodies swapped,
causing ISel to emit the wrong truth-table immediate whenever operand
reordering was needed (-O1+, not -O0).
Test changes:
- **avx512-vpternlog-commute.ll: regenerated with
update_llc_test_checks.py**
(accounts for the large diff)
- Added 4 new cases: vpternlog231_rmik, vpternlog312_rmik,
vpternlog231_rmbik, vpternlog312_rmbik
Tested: llvm-lit on llvm/test/CodeGen/X86 (no regressions), original
repro verified correct at -O0 through -O3, -Os, -Oz.
(cherry picked from commit bd38dd0ace19c3b9512da2b37bb9690ee6c9e97f)
[DWARFLinker] Fix RefTypeName crash and type-table non-determinism (#209033)
The parallel linker computes DIE placement (artificial type unit vs
plain DWARF) concurrently across compile units.
1. updateDependenciesCompleteness checked the placement of the enclosing
root type (getRootForSpecifiedEntry) instead of the actual referenced
DIE. A nested type can be demoted to plain DWARF while its root stays in
the type table, leaving a type-unit DIE that references a plain DIE and
tripping the RefTypeName assertion in
DIEAttributeCloner::cloneDieRefAttr. Carry the actual referenced DIE on
the worklist item and check its placement.
2. The completeness dependency set was recorded as a side effect of the
concurrent marking traversal, which short-circuits on already-marked
DIEs (isAlreadyMarked) before maybeAddReferencedRoots. When a shared
cross-CU DIE was already marked by a racing CU, the current referencing
root's outgoing dependencies were dropped, so the demotion fixpoint
missed demotions and whole type subtrees were left in the artificial
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[VPlan] Compute blend masks from minimum set of edge masks (#201783)
#201784 aims to preserve SSA in early exit loops, and in doing so insert
phi nodes. More phi nodes results in more VPBlendRecipes, so this PR
optimizes the edge masks generated for those blend recipes to prevent
regressions.
The idea is to compute a minimal set of edges that lead to each unique
incoming value in a phi. It does this by iterating up the edges in the
post dominance frontier till the outgoing edges no longer lead to the
same value.
This is a simpler, less general version of #184838 since this can't
optimize away edges that aren't postdominated by the phi. This is fine
the early exit use case though, since we only need to optimize phi nodes
inserted in the latch.
The big advantage over #184838 is that it doesn't require several
depth-first searches to compute the set of reachable nodes, and can be
done entirely by iterating the post-dominator frontier.
[libc][cmake] Add LIBC_TEST_SUBPROCESS_TESTS (#211238)
This replaces the ENABLE_SUBPROCESS_TESTS preprocessor flag with a cmake
variable. By lifting the logic into cmake, we select which test
framework files to build, and also exclude whole tests, if they do not
make sense without subprocess support.
This enables us to fix failures from (now reverted) #209999 and
#210889, as it will let us skip the *exit family of tests. The problem
there was that GPU targets support the *exit entry points (so the
auto-skipping logic does not kick in), but they do not have (and maybe
cannot have?) the functionality necessary to test them.
I convert two libgen tests (the only users of ENABLE_SUBPROCESS_TESTS)
to the new framework.
[compiler-rt][sanitizer_common] Size readlink/getsockopt post-hook unpoison by bytes written (#209209)
# About
`readlink`/`readlinkat` return the number of bytes placed in the buffer
in res and do not NUL-terminate it, and getsockopt writes *optlen bytes
of binary option data. The post-hooks instead sized their POST_WRITE
(MSan unpoison) with internal_strlen(buf) + 1, which reads past what the
kernel wrote -- over- unpoisoning the uninitialized tail (masking real
bugs) and, on a buffer with no NUL, reading out of bounds inside the
runtime. For binary option data an early zero byte instead
under-unpoisons.
Size the unpoison by the actual written length, matching the
corresponding libc interceptors (readlink unpoisons res bytes, and
getsockopt unpoisons *optlen bytes).
Seems to be present since the file's 2013 import.
[Support] parallelFor: enable caller participation (#209690)
`parallelFor` dispatches its work to the thread pool and blocks the
calling thread in the `TaskGroup` destructor until the workers finish.
The caller thus stays idle instead of joining the work as modern parallel
libraries do, and `numactl -C 0-7 ld.lld --threads=8` ends up slower than
`numactl -C 0-8 ld.lld --threads=8`.
Run one worker on the calling thread instead. This requires that no
`parallelFor` body reads `getThreadIndex()`, which is unset on the
caller; the last such user is removed by #209687.
In the jobserver mode: only pool workers acquire job slots, so a
jobserver-limited process may briefly exceed its granted concurrency by
one thread. This is acceptable, better than pessimizing the common
non-jobserver case, and parallelFor is unused by jobserver users.
[DebugInfo] Don't assert on missing template parameter names (#211412)
The DWARF verifier reconstructs simplified template names through
DWARFTypePrinter to compare them against the original DW_AT_name. On
malformed input, a template parameter can have no recoverable name,
which tripped assert(RawName) and aborted instead of letting the
verifier report the problem.
Assisted-by: Claude
rdar://182715403
