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
Before this patch there was no dependence visible to the optimizer between a
open_existential and the witness_method allowing the optimizer to reorder the
two instruction. The dependence was implicit in the opened archetype but this
is not a concept model by the SIL optimizer.
%2 = open_existential %0 : $*FooProto to $*@opened("...") FooProto
%3 = witness_method $@opened("...") FooProto,
#FooProto.bar!1 : $@cc(...)
%4 = apply %3<...>(%2)
This patch changes the SIL representation such that witness_methods on opened
archetypes take the open_existential (or the producer of the opened existential)
as an operand preventing the optimizer from reordering them.
%2 = open_existential %0 : $*FooProto to $*@opened("...") FooProto
%3 = witness_method $@opened("...") FooProto,
#FooProto.bar!1,
%2 : $*@opened("...") FooProto : $@cc(...)
%4 = apply %3<...>(%2)
rdar://18984526
Swift SVN r23438
Note that I did not change any actual memory behavior. That will come via a
later cleanup phase. Since this is a correctness fix I wanted to only make
things more conservative.
rdar://18568601
Swift SVN r23311
Specifically:
1. Given a struct literal with only one stored non-trivial field, a ref count
operation on the struct is equivalent to a ref count operation on the field.
2. Given a tuple literal with only one non-trivial elt , a ref count
operation on the tuple is equivalent to a ref count operation on the elt.
3. Given a tuple_extract, if the tuple_extract is extracting the only
non-trivial element of the tuple, a ref count on the tuple_extract is equivalent
to a ref count on the original type.
rdar://18499023
Swift SVN r22902
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
Simplify binary switches to select_enum instead of enum_is_tag, and make a first attempt at changing passes over to recognize limited forms of select_enum instead of enum_is_tag. There is one case in test/SILPasses/simplify_cfg.sil I wasn't able to figure out, and there are a lot more general passes we could define in terms of select_enum.
Swift SVN r22615
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
I think all the enums that identify operand position should be public.
I've noticed a number of places where we hard-code operand positions
which seems pretty horrible to me.
Swift SVN r22513
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
This matches the name for SwitchEnumInst::getCaseDestination() and includes the word
'unique' so that the name self documents.
I also removed a local function doing the same work in SimplifyCFG and changed
its user to use getUniqueCaseForDestination instead.
Swift SVN r21339
