This is a type that has ownership of a reference while allowing access to the
spare bits inside the pointer, but which can also safely hold an ObjC tagged pointer
reference (with no spare bits of course). It additionally blesses one
Foundation-coordinated bit with the meaning of "has swift refcounting" in order
to get a faster short-circuit to native refcounting. It supports the following
builtin operations:
- Builtin.castToBridgeObject<T>(ref: T, bits: Builtin.Word) ->
Builtin.BridgeObject
Creates a BridgeObject that contains the bitwise-OR of the bit patterns of
"ref" and "bits". It is the user's responsibility to ensure "bits" doesn't
interfere with the reference identity of the resulting value. In other words,
it is undefined behavior unless:
castReferenceFromBridgeObject(castToBridgeObject(ref, bits)) === ref
This means "bits" must be zero if "ref" is a tagged pointer. If "ref" is a real
object pointer, "bits" must not have any non-spare bits set (unless they're
already set in the pointer value). The native discriminator bit may only be set
if the object is Swift-refcounted.
- Builtin.castReferenceFromBridgeObject<T>(bo: Builtin.BridgeObject) -> T
Extracts the reference from a BridgeObject.
- Builtin.castBitPatternFromBridgeObject(bo: Builtin.BridgeObject) -> Builtin.Word
Presents the bit pattern of a BridgeObject as a Word.
BridgeObject's bits are set up as follows on the various platforms:
i386, armv7:
No ObjC tagged pointers
Swift native refcounting flag bit: 0x0000_0001
Other available spare bits: 0x0000_0002
x86_64:
Reserved for ObjC tagged pointers: 0x8000_0000_0000_0001
Swift native refcounting flag bit: 0x0000_0000_0000_0002
Other available spare bits: 0x7F00_0000_0000_0004
arm64:
Reserved for ObjC tagged pointers: 0x8000_0000_0000_0000
Swift native refcounting flag bit: 0x4000_0000_0000_0000
Other available spare bits: 0x3F00_0000_0000_0007
TODO: BridgeObject doesn't present any extra inhabitants. It ought to at least provide null as an extra inhabitant for Optional.
Swift SVN r22880
Modeling builtins as first-class function values doesn't really make sense because there's no real function value to emit, and modeling them this way complicates passes that work with builtins because they have to invent function types for builtin invocations. It's much more straightforward to have a single instruction that references the builtin by ID, along with the type information for the necessary values, type parameters, and results, so add a new "builtin" instruction that directly represents a builtin invocation. NFC yet.
Swift SVN r22690
with user code and that the boilerplate is counted towards the prologue.
<rdar://problem/18563763> Setting a breakpoint on "main" in a Swift program doesn't stop at user code
Swift SVN r22611
layouts. Introduce new SIL instructions to initialize
and open existential metatype values.
Don't actually, y'know, lift any of the restriction on
existential metatypes; just pointlessly burn extra
memory storing them.
Swift SVN r22592
For top level function decls, even if their SILFunctions are emitted, we still
print them. They are needed to satisfy protocol requirements.
Swift SVN r22586
This will be used for parsing sil generated from stdlib. We will ignore
the AST decls and instead import them from the module.
rdar://17979145
Swift SVN r22367
Now the SILLinkage for functions and global variables is according to the swift visibility (private, internal or public).
In addition, the fact whether a function or global variable is considered as fragile, is kept in a separate flag at SIL level.
Previously the linkage was used for this (e.g. no inlining of less visible functions to more visible functions). But it had no effect,
because everything was public anyway.
For now this isFragile-flag is set for public transparent functions and for everything if a module is compiled with -sil-serialize-all,
i.e. for the stdlib.
For details see <rdar://problem/18201785> Set SILLinkage correctly and better handling of fragile functions.
The benefits of this change are:
*) Enable to eliminate unused private and internal functions
*) It should be possible now to use private in the stdlib
*) The symbol linkage is as one would expect (previously almost all symbols were public).
More details:
Specializations from fragile functions (e.g. from the stdlib) now get linkonce_odr,default
linkage instead of linkonce_odr,hidden, i.e. they have public visibility.
The reason is: if such a function is called from another fragile function (in the same module),
then it has to be visible from a third module, in case the fragile caller is inlined but not
the specialized function.
I had to update lots of test files, because many CHECK-LABEL lines include the linkage, which has changed.
The -sil-serialize-all option is now handled at SILGen and not at the Serializer.
This means that test files in sil format which are compiled with -sil-serialize-all
must have the [fragile] attribute set for all functions and globals.
The -disable-access-control option doesn't help anymore if the accessed module is not compiled
with -sil-serialize-all, because the linker will complain about unresolved symbols.
A final note: I tried to consider all the implications of this change, but it's not a low-risk change.
If you have any comments, please let me know.
Swift SVN r22215
This is necessary to be able to properly stash values with nontrivial lowerings, such as metatypes and functions, inside existential containers. Modify SILGen to lower values to the proper abstraction level before storing them in an existential container. Part of the fix for rdar://problem/18189508, though runtime problems still remain when trying to actually dynamicCast out a metatype from an Any container.
Swift SVN r21830
We want to be able to work around problems with non-failable
Objective-C initializers actually failing, which can happen when the
API audit data incorrectly marks an initializer as non-failable.
Swift SVN r21711
The AST printer can't handle non-type-checked decls, so for now just only
print SIL if we're in -primary-file mode. That doesn't result in parseable
SIL, but it's better than crashing because we tried to print something
irrelevant from another file.
Swift SVN r21500
This will let the performance inliner inline a function even if the costs are too high.
This attribute is only a hint to the inliner.
If the inliner has other good reasons not to inline a function,
it will ignore this attribute. For example if it is a recursive function (which is
currently not supported by the inliner).
Note that setting the inline threshold to 0 does disable performance inlining at all and in
this case also the @inline(__always) has no effect.
Swift SVN r21452
This disables inlining at the SIL level. LLVM inlining is still enabled. We can
use this to expose one function at the SIL level - which can participate in
dominance based optimizations but which is implemented in terms of a cheap check
and an expensive check (function call) that benefits from LLVM's inlining.
Example:
The inline(late) in the example below prevents inlining of the two checks. We
can now perform dominance based optimizations on isClassOrObjExistential.
Without blocking inlining the optimizations would apply to the sizeof check
only and we would have multiple expensive function calls.
@inline(late)
func isClassOrObjExistential(t: Type) -> Bool{
return sizeof(t) == sizeof(AnyObject) &&
swift_isClassOrObjExistential(t)
}
We do want inlining of this function to happen at the LLVM level because the
first check is constant folded away - IRGen replaces sizeof by constants.
rdar://17961249
Swift SVN r21286
Fix a bug introduced in r20818, where we should print get for computed property.
Make sure we can round-trip extension of a generic class and extension of an
inner class.
rdar://17927072
Swift SVN r21151
...and 'assign' and 'unsafe_unretained' as 'unowned(unsafe)', if the
property is a class type.
This isn't important for the compiler, but it is documentation for users
when they look at the generated interface for an Objective-C module.
Note that this actually produces a decl users can't yet write:
unowned(unsafe) var foo: UIView!
That's <rdar://problem/17277899> unowned pointers can't be optional.
<rdar://problem/17245555>
Swift SVN r20433
Expose Substitution's archetype, replacement, and conformances only through getters so we can actually assert invariants about them. To start, require replacement types to be materializable in order to catch cases where the type-checker tries to bind type variables to lvalue or inout types, and require the conformance array to match the number of protocol conformances required by the archetype. This exposes some latent bugs in the test suite I've marked as failures for now:
- test/Constraints/overload.swift was quietly suffering from <rdar://problem/17507421>, but we didn't notice because we never tried to codegen it.
- test/SIL/Parser/array_roundtrip.swift doesn't correctly roundtrip substitutions, which I filed as <rdar://problem/17781140>.
Swift SVN r20418
*NOTE* This linkage is different from {Public,Hidden}External in that it has no
extra semantic meaning beyond shared.
The use of this linkage is to ensure that we do not serialize deserialized
shared functions. Those shared functions can always be re-deserialized from the
original module. This prevents a whole class of bugs related to the
creation of module cross references since all references to the shared
item go straight to the original module.
<rdar://problem/17772847>
Swift SVN r20375
Before this commit, we were not able to differentiate between stored
property and stored_with_trivial_accessors property. This causes issues
when parsing a SILDeclRef to a trivial getter.
We add @sil_stored for stored properties and we will have 3 cases
A) for stored property: @sil_storage var x : Int
B) for stored_with_trivial_accessors property:
@sil_storage var x : Int { get set }
C) for computed property: var x : Int { get set }
Fix rdar://17715778 rdar://17381432 rdar://17347296.
Swift SVN r20189
Add PrintForSIL in PrintOptions
1> for NameAliasType, we print getSinglyDesugaredType()
I attempted another option: set FullyQualifiedTypes of PrintOptions, but that
will print xxx.Type.xxx and Parser can’t handle it.
2> for Self, we print @sil_self
We also work around parsing:
sil_witness_table _CocoaArrayType: _CocoaArrayType
sil_vtable uses internal classes in stdlib, so we use lookupTopDecl instead
of lookupValue when parsing sil_vtable, to find internal classes.
Fix rdar://17261925 rdar://17295316 rdar://17046276 rdar://17579890
Swift SVN r20070
Enable SIL parsing and SIL serialization of semantics.
We add one more field to SILFunctionLayout for semantics. We should refactor
handling of attributes at SIL level, right now they are in SILFunction as bool
or std::string and in SIL serializer as a 1-bit field or an ID field.
rdar://17525564
Swift SVN r19434
