The main point of this change is to make sure that a shared function always has a body: both, in the optimizer pipeline and in the swiftmodule file.
This is important because the compiler always needs to emit code for a shared function. Shared functions cannot be referenced from outside the module.
In several corner cases we missed to maintain this invariant which resulted in unresolved-symbol linker errors.
As side-effect of this change we can drop the shared_external SIL linkage and the IsSerializable flag, which simplifies the serialization and linkage concept.
Introduce a new instruction `dealloc_stack_ref ` and remove the `stack` flag from `dealloc_ref`.
The `dealloc_ref [stack]` was confusing, because all it does is to mark the deallocation of the stack space for a stack promoted object.
This cleans up 90 instances of this warning and reduces the build spew
when building on Linux. This helps identify actual issues when
building which can get lost in the stream of warning messages. It also
helps restore the ability to build the compiler with gcc.
Fix innumerable latent bugs with iterator invalidation and callback invocation.
Removes dead code earlier and chips away at all the redundant copies the compiler generates.
Instead, put the archetype->instrution map into SIlModule.
SILOpenedArchetypesTracker tried to maintain and reconstruct the mapping locally, e.g. during a use of SILBuilder.
Having a "global" map in SILModule makes the whole logic _much_ simpler.
I'm wondering why we didn't do this in the first place.
This requires that opened archetypes must be unique in a module - which makes sense. This was the case anyway, except for keypath accessors (which I fixed in the previous commit) and in some sil test files.
Refactor SILGen's ApplyOptions into an OptionSet, add a
DoesNotAwait flag to go with DoesNotThrow, and sink it
all down into SILInstruction.h.
Then, replace the isNonThrowing() flag in ApplyInst and
BeginApplyInst with getApplyOptions(), and plumb it
through to TryApplyInst as well.
Set the flag when SILGen emits a sync call to a reasync
function.
When set, this disables the SIL verifier check against
calling async functions from sync functions.
Finally, this allows us to add end-to-end tests for
rdar://problem/71098795.
In SILCombine, we do not want to add or delete edges. We are ok with swapping
edges or replacing edges when the CFG structure is preserved. This becomes an
issue since by performing this optimization, we are going to get rid of the
error parameter but leave a try_apply, breaking SIL invariants. So to do perform
this optimization, we would need to convert to an apply and eliminate the error
edge, breaking the aforementioned SILCombine invariant. So, just do not perform
this for now and leave it to other passes like SimplifyCFG.
If we know that we have a FunctionRefInst (and not another variant of FunctionRefBaseInst), we know that getting the referenced function will not be null (in contrast to FunctionRefBaseInst::getReferencedFunctionOrNull).
NFC
TLDR: This is just an NFC rename in preparation for changing
SILValue::getOwnershipKind() of any forwarding instructions to return
OwnershipKind::None if they have a trivial result despite forwarding ownership
that isn't OwnershipKind::None (consider an unchecked_enum_data of a trivial
payload from a non-trivial enum).
This ensures that one does not by mistake use this routine instead of
SILValue::getOwnershipKind(). The reason why these two things must be
distinguished is that the forwarding ownership kind of an instruction that
inherits from OwnershipForwardingMixin is explicitly not the ValueOwnershipKind
of the result of the instruction. Instead it is a separate piece of state that:
1. For certain forwarding instructions, defines the OwnershipConstraint of the
forwarding instruction.
2. Defines the ownership kind of the result of the value. If the result of the
value is non-trivial then it is exactly the set ownership kind. If the result is
trivial, we use OwnershipKind::None instead. As an example of this, consider an
unchecked_enum_data that extracts from a non-trivial enum a trivial payload:
```
enum Either {
case int(Int)
case obj(Klass)
}
%1 = load_borrow %0 : $*Either
%2 = unchecked_enum_data %1 : $Either, #Either.int!enumelt.1 // Int type
end_borrow %1 : $Either
```
If we were to identify the forwarding ownership kind (guaranteed) of
unchecked_enum_data with the value ownership kind of its result, we would
violate ownership since we would be passing a guaranteed value to the operand of
the unchecked_enum_data that will only accept values with
OwnershipKind::None. =><=.
All of the non-SILCombiner specific helpers have already been updated for OSSA,
so this was not too bad.
NOTE: I also added two small combines that delete copy_value, destroy_value with
.none arguments. The reason why I added this is that this is a pretty small
addition and many of the tests of this code rely on SILCombine being able to
eliminate such operations on thin_to_thick_function.
NOTE: I also disabled TypePropagation in OSSA, we are going to redo that code
when we bring up opaque values.
This works around an issue where using an apply with an unsubstituted
substitution map causes issues in downstream optimizations.
```
%9 = alloc_stack $@opened("60E354F4-17B9-11EB-9427-ACDE48001122") NonClassProto
copy_addr %8 to [initialization] %9 : $*@opened("60E354F4-17B9-11EB-9427-ACDE48001122") NonClassProto
%11 = witness_method $ConformerClass, #NonClassProto.myVariable!getter : <Self where Self : NonClassProto> (Self) -> () -> SomeValue :
$@convention(witness_method: NonClassProto) <τ_0_0 where τ_0_0 : NonClassProto> (@in_guaranteed τ_0_0) -> SomeValue
apply %11<@opened("60E354F4-17B9-11EB-9427-ACDE48001122") NonClassProto>(%9) : $@convention(witness_method: NonClassProto) <τ_0_0 where τ_0_0 : NonClassProto> (@in_guaranteed τ_0_0) -> SomeValue
```
The problem arise when the devirtualizer replace
`witness_method $ConformerClass, #NonClassProto.myVariable!getter` with the
underlying implementation. That implementation for better or worse is further
constrained to `Self : ConformerClass` and applying an opened existential
which is not class constraint is a recipe for disaster. The proper
solution would probably be for the devirtualizer to insert the cast if necessary
and update the substitution list.
That fix will be left for another day though.
rdar://70582785
This caused a problem when propagating the concrete type of an existential: if the concrete type is itself an opened existential, it was not added to the OpenedArchetypeTracker.
https://bugs.swift.org/browse/SR-13444
rdar://problem/68077098
This reinstates commit d7d829c059 with a fix for C tail-allocated arrays.
Replace a call of the getter of AnyKeyPath._storedInlineOffset with a "constant" offset, in case of a keypath literal.
"Constant" offset means a series of struct_element_addr and tuple_element_addr instructions with a 0-pointer as base address.
These instructions can then be lowered to "real" constants in IRGen for concrete types, or to metatype offset lookups for generic or resilient types.
Replace:
%kp = keypath ...
%offset = apply %_storedInlineOffset_method(%kp)
with:
%zero = integer_literal $Builtin.Word, 0
%null_ptr = unchecked_trivial_bit_cast %zero to $Builtin.RawPointer
%null_addr = pointer_to_address %null_ptr
%projected_addr = struct_element_addr %null_addr
... // other address projections
%offset_ptr = address_to_pointer %projected_addr
%offset_builtin_int = unchecked_trivial_bit_cast %offset_ptr
%offset_int = struct $Int (%offset_builtin_int)
%offset = enum $Optional<Int>, #Optional.some!enumelt, %offset_int
rdar://problem/53309403
Replace a call of the getter of AnyKeyPath._storedInlineOffset with a "constant" offset, in case of a keypath literal.
"Constant" offset means a series of struct_element_addr and tuple_element_addr instructions with a 0-pointer as base address.
These instructions can then be lowered to "real" constants in IRGen for concrete types, or to metatype offset lookups for generic or resilient types.
Replace:
%kp = keypath ...
%offset = apply %_storedInlineOffset_method(%kp)
with:
%zero = integer_literal $Builtin.Word, 0
%null_ptr = unchecked_trivial_bit_cast %zero to $Builtin.RawPointer
%null_addr = pointer_to_address %null_ptr
%projected_addr = struct_element_addr %null_addr
... // other address projections
%offset_ptr = address_to_pointer %projected_addr
%offset_builtin_int = unchecked_trivial_bit_cast %offset_ptr
%offset_int = struct $Int (%offset_builtin_int)
%offset = enum $Optional<Int>, #Optional.some!enumelt, %offset_int
rdar://problem/53309403
The static analyzer flags this as a nullptr dereference since FullApplySite::isa
can fail if given a non-ApplySite. Of course though, the SILInstruction is an
apply! We just created it! This commit helps the static analyzer by propagating
this type information by not downcasting our ApplyInst to SILInstruction and
then just use FullApplySite's ApplyInst constructor instead.
This became necessary after recent function type changes that keep
substituted generic function types abstract even after substitution to
correctly handle automatic opaque result type substitution.
Instead of performing the opaque result type substitution as part of
substituting the generic args the underlying type will now be reified as
part of looking at the parameter/return types which happens as part of
the function convention apis.
rdar://62560867
When performing the substitution of the 'concrete' type that happens to
be an opened archetype we need to force the substitution to actually
call the conformance remapping function.
rdar://62202282
SR-12571
I am going to use this in mandatory combine, and it seems like a generally
useful transformation.
I also updated the routine to construct its own SILBuilder that injects a user
passed in SILBuilderContext eliminating the bad pattern of passing in
SILBuilders.
This should be an NFC change.
Disable `SILCombiner::visitPartialApplyInst` from rewriting `partial_apply` with
with `@convention(method)` callee to `thin_to_thick_function`.
This fixes SIL verification errors: `thin_to_thick_function` only supports
`@convention(thin)` operands.
Resolves SR-12548.
A partial_apply of a function_ref whose body consists of just an
apply of a witness_method can be simplified down to a simple
partial_apply of the witness_method:
sil @foo:
%fn = witness_method ...
%result = apply %fn(...)
return %result
sil @bar:
%fn = function_ref @foo
%closure = partial_apply %fn(...)
===>
sil @bar:
%fn = witness_method ...
%closure = partial_apply %fn(...)
Instead of bailing on ownership functions in SILCombine::run, we will
bail in individual visitors. This way, as SILCombine is updated we can
paritially support ownership across the pass.
I was inconsistently providing initialized or uninitialized memory
to the callback when projecting a settable address, depending on
component type. We should always provide an uninitialized address.
We have an optimization in SILCombiner that "inlines" the use of compile-time constant key paths by performing the property access directly instead of calling a runtime function (leading to huge performance gains e.g. for heavy use of @dynamicMemberLookup). However, this optimization previously only supported key paths which solely access stored properties, so computed properties, optional chaining, etc. still had to call a runtime function. This commit generalizes the optimization to support all types of key paths.
I was inconsistently providing initialized or uninitialized memory
to the callback when projecting a settable address, depending on
component type. We should always provide an uninitialized address.
Changes:
* Allow optimizing partial_apply capturing opened existential: we didn't do this originally because it was complicated to insert the required alloc/dealloc_stack instructions at the right places. Now we have the StackNesting utility, which makes this easier.
* Support indirect-in parameters. Not super important, but why not? It's also easy to do with the StackNesting utility.
* Share code between dead closure elimination and the apply(partial_apply) optimization. It's a bit of refactoring and allowed to eliminate some code which is not used anymore.
* Fix an ownership problem: We inserted copies of partial_apply arguments _after_ the partial_apply (which consumes the arguments).
* When replacing an apply(partial_apply) -> apply and the partial_apply becomes dead, avoid inserting copies of the arguments twice.
These changes don't have any immediate effect on our current benchmarks, but will allow eliminating curry thunks for existentials.
args
createApplyWithConcreteType used to update Apply unconditionally. There
may have been cases prior to supporting store instructions that
miscompiled because of this but, there are certainly cases after
supporting store instructions. Therefore, it is important that the apply is updated only when the substitution can accept the new args.
