Use begin_unpaired_access [no_nested_conflict] for
Builtin.performInstantaneousReadAccess. This can't be optimized away
and is the proper marker to use when the access scope is unknown.
Drop the requirement that
_semantics("optimize.sil.preserve_exclusivity") be @inline(never). We
actually want theses inlined into user code. Verify that the
@_semantic functions are not inlined or otherwise tampered with prior
to serialization.
Make *no* change to propagate @inline(__always) into LLVM. This no longer has
any relationship to this PR and can be investigated seperately.
Since the functions produce pointers with tightly-scoped lifetimes there's no formal reason these have to only work on `inout` things. Now that arguments can be +0, we can even do this without copying values that we already have at +0.
NOTE:
1. This can not happen today with the +1 runtime.
2. This is tested by an updated builtins.swift test for +0 that I am going to
commit in a little bit.
3. We immediately forward the value when we put it into memory.
rdar://34222540
Otherwise, we break SILGen tests when they are updated for +0. This breakage
occurs since we use the original cleanup from args[0] instead of forwarding that
cleanup and creating a new cleanup on the result.
rdar://34222540
This eliminates a case where we were not moving a cleanup onto a forwarding case
and instead just jammed the original cleanup and the new value into 1 managed
value.
NFC, but helps the ownership verifier.
rdar://34222540
* Reduce array abstraction on apple platforms dealing with literals
Part of the ongoing quest to reduce swift array literal abstraction
penalties: make the SIL optimizer able to eliminate bridging overhead
when dealing with array literals.
Introduce a new classify_bridge_object SIL instruction to handle the
logic of extracting platform specific bits from a Builtin.BridgeObject
value that indicate whether it contains a ObjC tagged pointer object,
or a normal ObjC object. This allows the SIL optimizer to eliminate
these, which allows constant folding a ton of code. On the example
added to test/SILOptimizer/static_arrays.swift, this results in 4x
less SIL code, and also leads to a lot more commonality between linux
and apple platform codegen when passing an array literal.
This also introduces a couple of SIL combines for patterns that occur
in the array literal passing case.
These will be used for unit-testing the Type::join functionality in the
type checker. The result of the join is replaced during constraint
generation with the actual type.
There is currently no checking for whether the arguments can be used to
statically compute the value, so bad things will likely happen if
e.g. they are type variables. Once more of the basic functionality of
Type::join is working I'll make this a bit more bullet-proof in that
regard.
They include:
// Compute the join of T and U and return the metatype of that type.
Builtin.type_join<T, U, V>(_: T.Type, _: U.Type) -> V.Type
// Compute the join of &T and U and return the metatype of that type.
Builtin.type_join_inout<T, U, V>(_: inout T, _: U.Type) -> V.Type
// Compute the join of T.Type and U.Type and return that type.
Builtin.type_join_meta<T, U, V>(_: T.Type, _: U.Type) -> V.Type
I've added a couple simple tests to start off, based on what currently
works (aka doesn't cause an assert, crash, etc.).
This is already an RValue invariant that used to be enforced upon RValue
construction. We put in a hack to work around a bug where that was not occuring
and changed RValue constructors to instead load stored objects when they needed
to. But the problem is that since then we have added more constructors that
provide other manners to create such an invalid RValue.
I added verification to many parts of RValue and exposed an additional verify
method that we can invoke at the end of emitRValue() eventually to verify our
invariants. This will give me the comfort to make that assumption in other parts
of SILGen without worry.
I also performed a small amount of cleanup of RValue construction.
rdar://33358110
SILBuilder now tracks data dependencies between instructions
that open existentials and uses of the opened type, so
SILGen's mechanism for this is no longer needed.
In particular, this simplifies ArchetypeCalleeBuilder.
With the introduction of special decl names, `Identifier getName()` on
`ValueDecl` will be removed and pushed down to nominal declarations
whose name is guaranteed not to be special. Prepare for this by calling
to `DeclBaseName getBaseName()` instead where appropriate.
Previously often times when casting a value, we would just pass along the
cleanup of the uncasted value. With semantic SIL this is no longer correct since
the cleanup now needs to be on the cast result.
This caused problems for certain usages of Builtin.castToNativeObject(...) by
the stdlib. Specifically, the stdlib was using this on AnyObject values that
were not necessarily native. Since we were recreating the cleanup on the native
value, a swift native release was being used =><=.
In this commit I solve this problem by:
1. Adding an assert in Builtin.castToNativeObject(...) that ensures that any value
passed to Builtin.castToNativeObject() is known conservatively to use swift
native reference counting.
2. I changed all uses where we do not have a precondition of a native ref
counting type to use Builtin.castToUnknownObject(...).
3. I added a new Builtin called Builtin.unsafeCastToNativeObject(...) that does
not have the compile time check. I used this to rewrite callsites in the stdlib
where we know via preconditions that an AnyObject will dynamically always be
native.
rdar://29791263
...and IRGen it into a call to __tsan_write1 in compiler-rt. This is
preparatory work for a later patch that will add an experimental
option to treat Swift inout accesses as TSan writes.
There are many cases where getBufferForExpr and manageBufferForExpr occur right
next to each other. The closure based API expresses this pattern in a more
convenient manner where the user can express his/her intent with one action
instead of two. In these cases, the split is messy and not necessary.
This is actually a NFC change since we forward the cleanup in most cases and the
forwarding behavior is tested already by SILGen. But what this /does/ do is
prevent us from creating a ManagedValue that is "owned" but does not have a
cleanup.
rdar://29791263
SubstitutionList is going to be a more compact representation of
a SubstitutionMap, suitable for inline allocation inside another
object.
For now, it's just a typedef for ArrayRef<Substitution>.
The RValue(ArrayRef<ManagedValue>, CanType) constructor was intended as a semi-private interface for building an RValue from a pre-exploded array of elements, but was (understandably) widely being misused as a general ManagedValue-to-RValue constructor, causing crashes when working with tuples in various contexts where RValue's methods expected them to be exploded. Make the constructor private and update most improper uses of it to use the exploding RValue constructor, or to use a new `RValue::withPreExplodedElements` static method that more explicitly communicates the intent of the constructor. Fixes rdar://problem/29500731.
Keep in mind that these are approximations that will not impact correctness
since in all cases I ensured that the SIL will be the same after the
OwnershipModelEliminator has run. The cases that I was unsure of I commented
with SEMANTIC ARC TODO. Once we have the verifier any confusion that may have
occurred here will be dealt with.
rdar://28685236
I am removing these usages of this API since it conflicts with SILGen's want to
hold onto copy_value return values for ownership propagation purposes. If any of
the copy_value are folded, the reference that SILGen holds onto will be
invalid.
rdar://28685236
Today, loads and stores are treated as having @unowned(unsafe) ownership
semantics. This leaves the user to specify ownership changes on the loaded or
stored value independently of the load/store by inserting ARC operations. With
the change to Semantic SIL, this will no longer be true. Instead loads, stores
have ownership semantics that one must reason about such as copy, take, and
trivial.
This change moves us closer to that world by eliminating the default
OwnershipQualification argument from create{Load,Store}. This means that the
compiler developer cannot ignore reasoning about the ownership semantics of the
memory operation that they are creating.
Operationally, this is a NFC change since I have just gone through the compiler
and updated all places where we create loads, stores to pass in the former
default argument ({Load,Store}OwnershipQualifier::Unqualified), to
SILBuilder::create{Load,Store}(...). For now, one can just do that in situations
where one needs to create loads/stores, but over time, I am going to tighten the
semantics up via the verifier.
rdar://28685236
It's the same thing as for alloc_ref: the optional [tail_elems ...] attribute specify the tail elements to allocate.
For details see docs/SIL.rst
This feature is needed so that we can allocate a MangedBuffer with alloc_ref_dynamic.
The ManagedBuffer.create() function uses the dynamic self type to create the buffer instance.
Those builtins are: allocWithTailElems_<n>, getTailAddr and projectTailElems
Also rename the "gep" builtin, which indexes raw bytes, to "gepRaw" and add a new "gep" builtin to index in a typed array.
Those builtins are: allocWithTailElems_<n>, getTailAddr and projectTailElems
Also rename the "gep" builtin, which indexes raw bytes, to "gepRaw" and add a new "gep" builtin to index in a typed array.