Generalizes the ConcreteExistentialInfo abstraction so it can be used
both by the ExistentialSpecializer and SILCombine, allowing redundant
code in ExistentialSpecializer.cpp to be deleted.
Splits OpenedArchetypeInfo from ConcreteExistentialInfo. Adds a
ConcreteOpenedArchetypeInfo convenience wrapper around them both, for
use wherever we were originally using ConcreteExistentialInfo.
Splits getAddressOfStackInit into getStackInitInst, This is cleaner and
allows both the ExistentialSpecializer and SILCombine to handle more
interesting cases in the future, like unconditional_checked_cast.
Creates utilities, initializeSubstitutionMap, and
initializeConcreteTypeDef to simplify an generalize
ConcreteExistentialInfo.
While rewriting ExistentialSpecializer to use the new
abstraction, I fixed a latent bug in which is was using a SIL
argument index as a function type parameter index (this would
have broken up if/when we decide to enable calls with indirect
results).
I am going to leave in the infrastructure around this just in case. But there is
no reason to keep this in the tests themselves. I can always just revert this
and I don't think merge conflicts are likely due to previous work I did around
the tooling for this.
This addresses the unsupported case outlined in the FIXME.
We have an init_existential_{addr,ref} instruction which
constructs an existential of type R from a value whose
concrete type conforms to R.
Later on, we have a witness_method invoking a method of P,
where R refines Q refines P.
In order to give the witness_method instruction the correct
conformance after substituting the concrete type, we would
call ProtocolConformanceRef::getInherited().
However, this only supported a single level of protocol
refinement, so we would just bail out in the unsupported
case. Instead, this patch builds a SubstitutionMap from the
generic signature <T : R>, and uses the SubstitutionMap to
perform the conformance lookup of T to P.
Indirectly inherited conformances cannot be properly handled yet due to some representation issues with init_existential_* instructions.
This fixes a compiler crash reported in rdar://34022255.
Specializations are implementation details, and thus shouldn't be
public, even if they are specializing a public function. Without this
downgrade, the ABI of a module depends on random internal code
(could change inlining decisions etc.), as well as swiftc's optimiser.
This reverts commit 1b3d29a163, reversing
changes made to b32424953e.
We're seeing a handful of issues from turning on inlining of generics,
so I'm reverting to unblock the bots.
One minor revision: this lifts the proposed restriction against
overriding a non-open method with an open one. On reflection,
that was inconsistent with the existing rule permitting non-public
methods to be overridden with public ones. The restriction on
subclassing a non-open class with an open class remains, and is
in fact consistent with the existing access rule.
Several functionalities have been added to FSO over time and the logic has become
muddled.
We were always looking at a static image of the SIL and try to reason about what kind of
function signature related optimizations we can do.
This can easily lead to muddled logic. e.g. we need to consider 2 different function
signature optimizations together instead of independently.
Split 1 single function to do all sorts of different analyses in FSO into several
small transformations, each of which does a specific job. After every analysis, we produce
a new function and eventually we collapse all intermediate thunks to in a single thunk.
With this change, it will be easier to implement function signature optimization as now
we can do them independently now.
Small modifications to the test cases.
While I'm in this code, generalize it to propagate the original
type information in more cases, including when the original type
is still dependent, and teach it to handle existential metatypes.
rdar://24114020
