If the compiler can prove that a throwing function actually does not throw it can
replace a try_apply with an "apply [nothrow]". Such an apply_inst calls a function
with an error result but does not have the overhead of checking for the error case.
Currently this flag is not set, yet.
Swift SVN r31151
dealloc_ref [destructor] is the existing behavior. It expects the
reference count to have reached zero and the isDeallocating bit to
be set.
The new [constructor] variant first drops the initial strong
reference.
This allows DI to properly free uninitialized instances in
constructors. Previously this would fail with an assertion if the
runtime was built with debugging enabled.
Progress on <rdar://problem/21991742>.
Swift SVN r31142
This flag is required for performing the propagation of global and static "let" values into their uses.
Let variables have now a [let] attribute in the SIL textual form.
Swift SVN r30153
We need a SIL level unsafe cast that supports arbitrary usage of
UnsafePointer, generalizes Builtin.reinterpretCast, and has the same
semantics on generic vs. nongeneric code. In other words, we need to
be able to promote the cast of an address type to the cast of an
object type without changing semantics, and that cast needs to support
types that are not layout identical.
This patch introduces an unchecked_bitwise_cast instruction for that
purpose. It is different from unsafe_addr_cast, which has been our
fall-back "unknown" cast in the past. With unchecked_bitwise_cast we
cannot assume layout or RC identity. The cast implies a store and
reload of the value to obtain the low order bytes. I know that
bit_cast is just an abbreviation for bitwise_cast, but we use
"bitcast" throught to imply copying a same sized value. No one could
come up with a better name for copying an objects low bytes via:
@addr = alloca $wideTy
store @addr, $wideTy
load @addr, $narrowTy
Followup patches will optimize unchecked_bitwise_cast into more
semantically useful unchecked casts when enough type information is
present. This way, the optimizer will rarely need to be taught about
the bitwise case.
Swift SVN r29510
Still no implementation yet; we'll need to renovate how boxes work a bit to make them projectable (and renovate SILGen to generate typed boxes for the insn to be useful).
Swift SVN r29490
This reverts commit r29475 because it conflicts with reverting r29474,
and it looks like that commit is breaking the build of the SpriteKit
overlay.
Swift SVN r29481
Still no implementation yet; we'll need to renovate how boxes work a bit to make them projectable (and renovate SILGen to generate typed boxes for the insn to be useful).
Swift SVN r29475
Make unqualified lookup always provide a declaration for the things it
finds, rather than providing either a module or a declaration. Unify
various code paths in our type checker now that module declarations
come in with the other declarations.
Swift SVN r28286
Preparation to fix <rdar://problem/18151694> Add Builtin.checkUnique
to avoid lost Array copies.
This adds the following new builtins:
isUnique : <T> (inout T[?]) -> Int1
isUniqueOrPinned : <T> (inout T[?]) -> Int1
These builtins take an inout object reference and return a
boolean. Passing the reference inout forces the optimizer to preserve
a retain distinct from what’s required to maintain lifetime for any of
the reference's source-level copies, because the called function is
allowed to replace the reference, thereby releasing the referent.
Before this change, the API entry points for uniqueness checking
already took an inout reference. However, after full inlining, it was
possible for two source-level variables that reference the same object
to appear to be the same variable from the optimizer's perspective
because an address to the variable was longer taken at the point of
checking uniqueness. Consequently the optimizer could remove
"redundant" copies which were actually needed to implement
copy-on-write semantics. With a builtin, the variable whose reference
is being checked for uniqueness appears mutable at the level of an
individual SIL instruction.
The kind of reference count checking that Builtin.isUnique performs
depends on the argument type:
- Native object types are directly checked by reading the
strong reference count:
(Builtin.NativeObject, known native class reference)
- Objective-C object types require an additional check that the
dynamic object type uses native swift reference counting:
(Builtin.UnknownObject, unknown class reference, class existential)
- Bridged object types allow the dymanic object type check to be
bypassed based on the pointer encoding:
(Builtin.BridgeObject)
Any of the above types may also be wrapped in an optional. If the
static argument type is optional, then a null check is also performed.
Thus, isUnique only returns true for non-null, native swift object
references with a strong reference count of one.
isUniqueOrPinned has the same semantics as isUnique except that it
also returns true if the object is marked pinned regardless of the
reference count. This allows for simultaneous non-structural
modification of multiple subobjects.
In some cases, the standard library can dynamically determine that it
has a native reference even though the static type is a bridge or
unknown object. Unsafe variants of the builtin are available to allow
the additional pointer bit mask and dynamic class lookup to be
bypassed in these cases:
isUnique_native : <T> (inout T[?]) -> Int1
isUniqueOrPinned_native : <T> (inout T[?]) -> Int1
These builtins perform an implicit cast to NativeObject before
checking uniqueness. There’s no way at SIL level to cast the address
of a reference, so we need to encapsulate this operation as part of
the builtin.
Swift SVN r27887
reference to something of class type. This is required to model
RebindSelfInConstructorExpr correctly to DI, since in the class case,
self.init and super.init *take* a value out of class box so that it
can pass the +1 value without performing an extra retain. Nothing
else in the compiler uninitializes a DI-controlled memory object
like this, so nothing else needs this. DI really doesn't like something
going from initialized to uninitialized.
Yes, I feel super-gross about this and am really unhappy about it. I
may end up reverting this if I can find an alternate solution to this
problem.
Swift SVN r27525
This is new attribute we're using to coalesce @thin, @objc_block, and @cc, and to extend to new uses like C function pointer types. Parse the new attribute, but preserve support for the old attributes, and print with the old attributes for now to separate out test changes. Migration fixits and test updates to come. I did take the opportunity here to kill off the '@cc(cdecl)' hack for AST-level function pointer types, which are now only spelt with @convention(c).
Swift SVN r27247
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
threaded into IRGen; tests to follow when that's done.
I made a preliminary effort to make the inliner do the
right thing with try_apply, but otherwise tried to avoid
touching the optimizer any more than was required by the
removal of ApplyInstBase.
Swift SVN r26747
As part of this, re-arrange the argument order so that
generic arguments come before the context, which comes
before the error result. Be more consistent about always
adding a context parameter on thick functions, even
when it's unused. Pull out the witness-method Self
argument so that it appears last after the error
argument.
Swift SVN r26667
We no longer need or use it since we can always refer to the same bit on
the applied function when deciding whether to inline during mandatory
inlining.
Resolves rdar://problem/19478366.
Swift SVN r26534
For better consistency with other address-only instruction variants, and to open the door to new exciting existential representations (such as a refcounted boxed representation for ErrorType).
Swift SVN r25902
If multiple swift files are compiled together, then guessing as to the
file when we emit IR obviously doesn't work. Find the filename when we
generate a function's coverage map and propagate it through SIL.
Swift SVN r25436
Keeping a reference to the function here is dangerous. We only
actually care about the name, so save ourselves a copy of that
instead.
This fixes a crash that seems to happen only when the coverage data is
very large.
Swift SVN r25433
Before if you had a differing number of arguments from types, you would
get the error:
Expected sil type to have the right argument types.
Now we say:
Expected sil type to have the same number of arg names as arg types.
which is slightly clearer.
Swift SVN r25049
This will have an effect on inlining into thunks.
Currently this flag is set for witness thunks and thunks from function signature optimization.
No change in code generation, yet.
Swift SVN r24998
1. Eliminate unused variable warnings.
2. Change field names to match capitalization of the rest of the field names in the file.
3. Change method names to match rest of the file.
4. Change get,set method for a field to match the field type.
Swift SVN r24501
storage for arbitrary values.
A buffer doesn't provide any way to identify the type of
value it stores, and so it cannot be copied, moved, or
destroyed independently; thus it's not available as a
first-class type in Swift, which is why I've labelled
it Unsafe. But it does allow an efficient means of
opaquely preserving information between two cooperating
functions. This will be useful for the adjustments I
need to make to materializeForSet to support safe
addressors.
I considered making this a SIL type category instead,
like $@value_buffer T. This is an attractive idea because
it's generally better-typed. The disadvantages are that:
- it would need its own address_to_pointer equivalents and
- alloc_stack doesn't know what type will be stored in
any particular buffer, so there still needs to be
something opaque.
This representation is a bit gross, but it'll do.
Swift SVN r23903
Using the intrinsics is obnoxious because I needed them
to return Builtin.NativeObject?, but there's no reasonable
way to safely generate optional types from Builtins.cpp.
Ugh.
Dave and I also decided that there's no need for
swift_tryPin to allow a null object.
Swift SVN r23824
SILMetadata is the base class with a single enum member (MDKind).
SILBranchNode is the derived class with additional members:
unsigned NumOperands
an array of uint32_t
A static member function SILBranchNode::get is implemented to get or create
SILBranchNode. All SILMetadata created are uniqued and saved in SILModule's
member variable:
llvm::FoldingSet<SILMetadata> Metadatas
Usage of SILMetadta by SILInstruction is captured in SILModule's member variable:
llvm::DenseMap<const SILInstruction *, SILMetadata *> MetadataStore
This is similar to LLVM's Metadata. Another option is to add a SILMetadata* to
SILInstruction. The disadvantage is the waste of space when we don't have PGO on.
This commit also enables parsing and printing of SILMetadata.
We add keyword sil_metadata to define SILMetadata:
sil_metadata !0 = {"branch_weights", 3, 5}
For parsing, we add a map in SILModule
llvm::DenseMap<unsigned, SILMetadata *> NumberedMetadata
that maps from ID to SILMetadata* to help matching usage of "!id" in SILFunction
with definition of "!id" in sil_metadata section.
For printing, we assign IDs to SILMetadata at SILModule scope, we then pass in
an optional argument of
llvm::DenseMap<const SILMetadata *, unsigned> *MetadataMap
to SILFunction::print in order to get the ID of SILMetadata used in
SILInstruction.
Post-commit review will be appreciated.
rdar://18269754
Swift SVN r23713
or pointer depends on another for validity in a
non-obvious way.
Also, document some basic value-propagation rules
based roughly on the optimization rules for ARC.
Swift SVN r23695
Make it easier to get the "do I expect null ProtocolConformance* pointers" logic right. Audit existing uses of is<ArchetypeType>() for this purpose.
Swift SVN r23479
And fix some bugs with existential conformances, where we were creating a bogus conformance instead of just using null conformances like other code expects.
Swift SVN r23461
