This PR removes the old `nocapture` attribute, replacing it with the new
`captures` attribute introduced in #116990. This change is
intended to be essentially NFC, replacing existing uses of `nocapture`
with `captures(none)` without adding any new analysis capabilities.
Making use of non-`none` values is left for a followup.
Some notes:
* `nocapture` will be upgraded to `captures(none)` by the bitcode
reader.
* `nocapture` will also be upgraded by the textual IR reader. This is to
make it easier to use old IR files and somewhat reduce the test churn in
this PR.
* Helper APIs like `doesNotCapture()` will check for `captures(none)`.
* MLIR import will convert `captures(none)` into an `llvm.nocapture`
attribute. The representation in the LLVM IR dialect should be updated
separately.
With this patch we track aligned barriers in AAExecutionDomain and also
delete unnecessary barriers there. This allows us to eliminate barriers
across blocks, across functions, and in the presence of complex accesses
that do not force a barrier. Further, we can use the collected
information to enable store-load forwarding in a threaded environment
(follow up patch).
Differential Revision: https://reviews.llvm.org/D140463
The Attributor has logic to run only on assumed live functions and this
is exposed to users now. OpenMP-opt will (mostly) ignore dead internal
functions now but run the same deduction as before if an internal
function is marked live.
This should lower compile time as we run on less code and delete more
code early on. For the full OpenMC module compiled with noinline and
JITed at runtime, we save ~25%, or ~10s on my machine during JITing.
When we see a store in generic mode we need to decide if we should guard
it for SPMDzation. This patch changes the getUnderlyingObjects call to
the more optimistic getAssumedUnderlyingObjects call to identify more
thread local pointers.
