[DFAJumpThreading] Try harder to avoid cycles in paths. (#169151)
If a threading path has cycles within it then the transformation is not
correct. This patch fixes a couple of cases that create such cycles.
Fixes https://github.com/llvm/llvm-project/issues/166868
[flang][OpenMP] Implement loop nest parser (#168884)
Previously, loop constructs were parsed in a piece-wise manner: the
begin directive, the body, and the end directive were parsed separately.
Later on in canonicalization they were all coalesced into a loop
construct. To facilitate that end-loop directives were given a special
treatment, namely they were parsed as OpenMP constructs. As a result
syntax errors caused by misplaced end-loop directives were handled
differently from those cause by misplaced non-loop end directives.
The new loop nest parser constructs the complete loop construct,
removing the need for the canonicalization step. Additionally, it is the
basis for parsing loop-sequence-associated constructs in the future.
It also removes the need for the special treatment of end-loop
directives. While this patch temporarily degrades the error messaging
for misplaced end-loop directives, it enables uniform handling of any
misplaced end-directives in the future.
[Clang] VectorExprEvaluator::VisitCallExpr / InterpretBuiltin - Allow AVX512 VPSHUFBITQMB intrinsics to be used in constexpr (#168100)
Resolves #161337
[UBSan] Fix test-darwin-interface.c on X86 Darwin with Internal Shell (#169105)
This test was failing with the internal shell due to the use of
subshells. This was not caught in my initial round of testing due to me
only using a M4 Mac for running my tests.
[InstCombine] Generalize trunc-shift-icmp fold from (1 << Y) to (Pow2 << Y) (#169163)
Extends the `icmp(trunc(shl))` fold to handle any power of 2 constant as
the shift base, not just 1. This generalizes the following patterns by
adjusting the comparison offsets by `log2(Pow2)`.
```llvm
(trunc (1 << Y) to iN) == 0 --> Y u>= N
(trunc (1 << Y) to iN) != 0 --> Y u< N
(trunc (1 << Y) to iN) == 2**C --> Y == C
(trunc (1 << Y) to iN) != 2**C --> Y != C
; to
(trunc (Pow2 << Y) to iN) == 0 --> Y u>= N - log2(Pow2)
(trunc (Pow2 << Y) to iN) != 0 --> Y u< N - log2(Pow2)
(trunc (Pow2 << Y) to iN) == 2**C --> Y == C - log2(Pow2)
(trunc (Pow2 << Y) to iN) != 2**C --> Y != C - log2(Pow2)
```
Proof: https://alive2.llvm.org/ce/z/2zwTkp
[Clang][X86] VectorExprEvaluator::VisitCallExpr / InterpretBuiltin - allow VPERMILPD/S variable mask intrinsics to be used in constexpr (#168861)
Allowing VPERMILPD/S intrinsics to be used in constexpr
Closes #167878
[Flang] Add -ffast-real-mod back for further control of MOD optimizations (#167118)
It turns out that having `-ffast-math` as the only option to control
optimizations for MOD for REAL kinds (PR #160660) is too coarse-grained
for some applications. Thus, this PR adds back `-ffast-real-mod` to have
more control over the optimization. The `-ffast-math` flag will still
enable the optimization, and `-fno-fast-real-mod` allows one to disable
it.
[CIR] Add support for non-compile-time memory order (#168892)
This patch upstreams CIR support for atomic operations with memory
orders that are not known at compile time.
Add new llvm.dbg.declare_value intrinsic. (#168132)
For swift async code, we need to use a debug intrinsic that behaves like
an llvm.dbg.declare but can take any location type rather than just a
pointer or integer.
To solve this, a new debug instrinsic called llvm.dbg.declare_value has
been created, which behaves exactly like an llvm.dbg.declare but can
take non pointer and integer location types.
More information here:
https://discourse.llvm.org/t/rfc-introduce-new-llvm-dbg-coroframe-entry-intrinsic/88269
This is the first patch as part of a stack of patches, with the one
succeeding it being: https://github.com/llvm/llvm-project/pull/168134
