In a few places, we have to be careful about the distinction between
"empty in this resilience domain" versus "empty in all resilience
domains". Make callers think about this by adding a parameter instead
of relying on them to check isFixedSize() as necessary first.
While making this change I noticed that the code for checking if
types are empty when computing extra inhabitants of structs and enums
might be slightly wrong in the face of resilience; I will revisit
this later.
It is still not clear to me when we access global variables from other
modules directly, versus using accessors; it seems to be controlled
by the -sil-serialize-all flag, rather than any language feature.
Until/if we add a @_fixed_layout equivalent for globals, I can't really
test direct access of globals from other modules; when we figure out
the story here I'll be able to add more tests and also tighten up
some isResilient() checks in the global code, but what's in there now
seems to work.
Allocate and project the buffer, respectively, adding the
necessary indirection required to handle the size not being
known until runtime.
For now we don't emit alloc_global instructions anywhere;
an upcoming change will add that at the SIL level.
Also I suspect debug info needs some work to handle the
extra indirection, I'll look into this soon.
Previously some parts of the compiler referred to them as "fields",
and most referred to them as "elements". Use the more generic 'elements'
nomenclature because that's what we refer to other things in the compiler
(e.g. the elements of a bracestmt).
At the same time, make the API better by providing "getElement" consistently
and using it, instead of getElements()[i].
NFC.
Swift SVN r26894
llvm::Optional lives in "llvm/ADT/Optional.h". Like Clang, we can get
Optional in the 'swift' namespace by including "swift/Basic/LLVM.h".
We're now fully switched over to llvm::Optional!
Swift SVN r22477
- A spot fix in SILGen for reabstracting the result of a downcast, which fixes checked casts to function types.
- Associate the layout information in type metadata records with the most abstract representation of the type. This is the correct thing to do in cases where we need the metadata as a tag for an opaque value--if we store a value in an Any, or pass it as an unconstrained generic parameter, we must maximally reabstract it. This fixes the value semantics of existentials containing trivial metatypes.
- To ensure that we get runtime layout of structs and enums correct when they contain reabstractable types, introduce a "metadata for layout" concept, which doesn't need to describe the canonical metadata for the type, but only needs to describe a type with equivalent layout and value semantics. This is a correctness fix that allows us to correctly lay out generic types containing dependent tuples and functions, and although we don't really take advantage of it here, it's also a potential runtime performance win down the road, because we could potentially produce direct metadata for a primitive type that's layout-equivalent with a runtime-instantiated type. To aid in type safety here, push SILType deeper into IRGen in places where we potentially care about specific representations of types.
- Finally, fix an inconsistency between the runtime and IRGen's concept of what spare bits unmanaged references and thick metatypes have.
Together, these fixes address rdar://problem/16406907, rdar://problem/17822208, rdar://problem/18189508, and likely many other related issues, and also fixes crash suite cases 012 and 024.
Swift SVN r21963
Update SILGen to create SILGlobalVariable and SILGlobalAddrInst instead of
GlobalAddrInst. When we see a definition for a global variable, we create
the corrsponding SILGlobalVariable definition.
When creating SILGlobalVariable from a global VarDecl, we mangle the global
VarDecl in the same way as we mangle it at IRGen. The SILLinkage is also
set in the same way as we set it at IRGen.
At IRGen, we use the associated VarDecl for SILGlobalVariable if it exists,
to have better debugging information.
We set the initializer for SILGlobalVariable definition only.
We also handle SILGlobalAddrInst in various SILPasses, in the similar way
as we handle GlobalAddrInst.
rdar://15493694
Swift SVN r21887
Failable initializers will need to clean up an uninitialized 'self' box in the case where a class initializer calls out to a 'super.init' or 'self.init' fails. Because some framework classes assume that they have a refcount of exactly one during initialization, we have to take 'self' from the box during the delegation, and reinitialize the box with the result of the delegation on success. This means we actually have to implement lowering for dealloc_box.
Swift SVN r21493
IRGen type conversion is invariant with respect to archetypes with the same set of constraints, so instead of redundantly generating a TypeInfo object and IR type for Optional<T> for every T everywhere, key TypeInfo objects using an "exemplar type" that we form using a folding set to collapse together archetypes with the same class-ness, superclass constraint, and protocol constraints.
This is a nice memory and IR size optimization, but will be essential for correctness when lowering interface types, because there is no unique context to ground a dependent type, and we need to lower the same generic parameter with the same context requirements to the same type whenever we instantiate it in order for the IR to type-check.
In this revision, we profile the nested archetypes of each recursively, which I neglected to take into account originally in r12112, causing failures when archetypes that differed by associated type constraints were incorrectly collapsed.
Swift SVN r12116
IRGen type conversion is invariant with respect to archetypes with the same set of constraints, so instead of redundantly generating a TypeInfo object and IR type for Optional<T> for every T everywhere, key TypeInfo objects using an "exemplar type" that we form using a folding set to collapse together archetypes with the same class-ness, superclass constraint, and protocol constraints.
This is a nice memory and IR size optimization, but will be essential for correctness when lowering interface types, because there is no unique context to ground a dependent type, and we need to lower the same generic parameter with the same context requirements to the same type whenever we instantiate it in order for the IR to type-check.
Swift SVN r12112
In general, this forces SILGen and IRGen code that's grabbing
a declaration to state whether it's doing so to define it.
Change SIL serialization to serialize the linkage of functions
and global variables, which means also serializing declarations.
Change the deserializer to use this stored linkage, even when
only deserializing a declaration, and to call a callback to
inform the client that it has deserialized a new entity.
Take advantage of that callback in the linking pass to alter
the deserialized linkage as appropriate for the fact that we
imported the declaration. This computation should really take
advantage of the relationship between modules, but currently
it does not.
Swift SVN r12090
The current implementation of dealloc_stack in IR-gen is a
no-op, but that's very much wrong for types with non-trivial
local allocation requirements, e.g. archetypes. So we need
to be able to do non-trivial code here. However, that means
modeling both the buffer pointer and the allocated address
in SIL.
To make this more type-safe, introduce a SIL-specific
'[local_storage] T' type that represents the required
allocation for locally storing a T. alloc_stack now returns
one of those in additon to a *T, and dealloc_stack expects
the former.
IR-gen still implements dealloc_stack as a no-op, but
that's now easy to fix.
Swift SVN r6937
their types.
- DebugTypeInfo holds all type info we need to emit debug information.
- Type info is limited to name, location, and storage size.
- As a side-effect: verbose LLVM IR allocas in debug builds!
Swift SVN r5980
For most types, this is really only useful in the presence of
an unimplemented operation, but for empty types this does come
up quite reasonably.
Swift SVN r4897
handling non-fixed layouts.
This uncovered a bug where we weren't rounding up the header
size to the element alignment when allocating an array of archetypes.
Writing up a detailed test case for *that* revealed that we were
never initializing the length field of heap arrays. Fixing that
caused a bunch of tests to crash trying to release stuff. So...
I've left this in a workaround state right now because I have to
catch a plane.
Swift SVN r4804
Set up IRGen to emit SIL code that uses top-level-code global variables. Add -sil-i to a bunch of Interpreter tests that use global variables.
Swift SVN r4480
Implement SIL-to-IR lowering for allocation, deallocation, load, store, and branching instructions so that local variables and branching control flow can be used. Add a Fibonacci loop test to exercise the new instructions.
Swift SVN r3767
The test changes are that we're setting a class body on
some types that we weren't before. For some of these,
this is okay; for others, it's more questionable, but
ultimately not *harmful*.
Swift SVN r3746