There's a buggy SIL verifier check that was previously tautological,
and it turns out that it's violated, apparently harmlessly. Since it
was already doing nothing, I've commented it out temporarily while
I figure out the right way to fix SILGen to get the invariant right.
Modeling nonescaping captures as @inout parameters is wrong, because captures are allowed to share state, unlike 'inout' parameters, which are allowed to assume to some degree that there are no aliases during the parameter's scope. To model this, introduce a new @inout_aliasable parameter convention to indicate an indirect parameter that can be written to, not only by the current function, but by well-typed, well-synchronized aliasing accesses too. (This is unrelated to our discussions of adding a "type-unsafe-aliasable" annotation to pointer_to_address to allow for safe pointer punning.)
This centralizes the entrypoints for creating SILFunctions. Creating a
SILFunction is intimately tied to a specific SILModule, so it makes sense to
either centralize the creation on SILModule or SILFunction. Since a SILFunction
is in a SILModule, it seems more natural to put it on SILModule.
I purposely created a new override on SILMod that exactly matches the signature
of SILFunction::create so that beyond the extra indirection through SILMod, this
change should be NFC. We can refactor individual cases in later iterations of
refactoring.
This reverts commit 422d46638e.
Jordan said that this change is incorrect. I am reverting the patch and plan to
investigate why we are deserializing shared_external functions with no body.
We do not allow external declarations with shared visibility. This commit makes
the serializer translate shared_external linkage to public_external because the
serialized functions will be available at runtime.
rdar://21989088
The SIL serializer can decide not to serialize the body of functions in the SIL
module, and only emit a declaration. If we keep the original linkage kind
(public, private, etc) then the deserialized module won't pass verification
because we do not allow internal functions to have external declarations. This
commit changes the linkage kind for the functions that the serializer decides to
emit as a declaration (without a body).
rdar://21989088
The drivers for this change are providing a simpler API to SIL pass
authors, having a more efficient of the in-memory representation,
and ruling out an entire class of common bugs that usually result
in hard-to-debug backend crashes.
Summary
-------
SILInstruction
Old New
+---------------+ +------------------+ +-----------------+
|SILInstruction | |SILInstruction | |SILDebugLocation |
+---------------+ +------------------+ +-----------------+
| ... | | ... | | ... |
|SILLocation | |SILDebugLocation *| -> |SILLocation |
|SILDebugScope *| +------------------+ |SILDebugScope * |
+---------------+ +-----------------+
We’re introducing a new class SILDebugLocation which represents the
combination of a SILLocation and a SILDebugScope.
Instead of storing an inline SILLocation and a SILDebugScope pointer,
SILInstruction now only has one SILDebugLocation pointer. The APIs of
SILBuilder and SILDebugLocation guarantees that every SILInstruction
has a nonempty SILDebugScope.
Developer-visible changes include:
SILBuilder
----------
In the old design SILBuilder populated the InsertedInstrs list to
allow setting the debug scopes of all built instructions in bulk
at the very end (as the responsibility of the user). In the new design,
SILBuilder now carries a "current debug scope" state and immediately
sets the debug scope when an instruction is inserted.
This fixes a use-after-free issue with with SIL passes that delete
instructions before destroying the SILBuilder that created them.
Because of this, SILBuilderWithScopes no longer needs to be a template,
which simplifies its call sites.
SILInstruction
--------------
It is neither possible or necessary to manually call setDebugScope()
on a SILInstruction any more. The function still exists as a private
method, but is only used when splicing instructions from one function
to another.
Efficiency
----------
In addition to dropping 20 bytes from each SILInstruction,
SILDebugLocations are now allocated in the SILModule's bump pointer
allocator and are uniqued by SILBuilder. Unfortunately repeat compiles
of the standard library already vary by about 5% so I couldn’t yet
produce reliable numbers for how much this saves overall.
rdar://problem/22017421
This reflects the fact that the attribute's only for compiler-internal use, and isn't really equivalent to C's asm attribute, since it doesn't change the calling convention to be C-compatible.
This is all effectively NFC, but lays out the shape of the iterative
type checker: requests are packaged up in TypeCheckRequest, we can
check whether the request has been satisfied already (isSatisfied),
enumerate its dependencies (enumerateDependenciesOf) in terms of other
TypeCheckRequests, and satisfy a request (satisfy).
Lazily-computed semantic information is captured directly in the
AST, but has been set aside in its own structure to allow us to
experiment with moving it into a lookaside table.
The only request that exists now is to type-check the superclass of
the given class. It currently performs unhealthy recursion into the
existing type checker. As we detangle dependencies, this recursion
between the IterativeTypeChecker and the TypeChecker can go away.
Swift SVN r32558
GenericSignature's factory method determining whether the signature
was canonical based solely on whether the types in the parameters and
requirments were canonical. While that is currently true (for legacy
reasons), it is wrong: canonicalization also needs to canonicalize
requirements, including same-type requirements, as is currently done
in the canonical signature "for mangling". Move the "this is
canonical" dependency to the point where the canonical signature is
actually computed, so we can change the definition of canonical
signatures later.
While we're here, don't eagerly compute the canonical generic
signature in GenericSignature::getASTContext().
Swift SVN r32309
This makes Swift (a) more likely to prefer frameworks over bare headers,
reducing potential issues with non-modular headers, and (b) more likely
to fail in the same way as LLDB if the -Xcc options also contain or affect
search paths.
rdar://problem/22413525
Swift SVN r31950
Also, suggest "xcrun swiftc" instead of "xcrun swift" on OS X, since
"swift" already infers SDKs and we shouldn't get into this situation.
(We shouldn't get into it on non-OS-X either thanks to the previous
commit, but just in case.)
rdar://problem/22440615
Swift SVN r31535
Apart from being general compile-time goodness, this helps break a
circularity issue involving serialization cross-references and the
Clang importer.
The test is being added to validation-tests because it relies on
several levels of non-laziness in the compiler, all of which we'd
like to fix. It's making sure we don't regress here, but it isn't
actually verifying this change in particular.
rdar://problem/22364953
Swift SVN r31455
Now that we have the inheritance lists hanging around, use them: it
makes the conformance lookup table use the same code whether we're
deserializing the conformances or parsing them.
Swift SVN r31383
The conformance lookup table is responsible for answering queries
about the protocols to which a particular nominal type conforms, so
stop storing (redundant and incorrect) protocol lists on the ASTs for
nominal types. Protocol types still store the list of protocols that
they inherit, however.
As a drive-by, stop lying about the number of bits that ProtocolDecl
uses on top of NominalTypeDecl, and move the overflow bits down into
ProtocolDecl itself so we don't bloat Decl unnecessarily.
Swift SVN r31381
These never appear in Swift code, but they can appear when serializing the
full output of SILGen ("SIB" format) because that includes code synthesized
for imported Clang declarations.
rdar://problem/22098491
Swift SVN r31364
This provides better AST fidelity through module files and further
reduces our dependencies on storing a list of protocols on nominal
type declarations.
Swift SVN r31345
This improves the fidelity of the AST printed from a loaded module, as
well as consistency in the AST. Also teach the Clang importer to add
"inherited" clauses, providing better fidelity for the mapping from
Objective-C to Swift.
With trivial update to SDKAnalyzer test.
Swift SVN r31344
This improves the fidelity of the AST printed from a loaded module, as
well as consistency in the AST. Also teach the Clang importer to add
"inherited" clauses, providing better fidelity for the mapping from
Objective-C to Swift.
Swift SVN r31337
We're no longer using this information for generic type parameters or
associated types, so there's no point in leaving this honeypot
around. Note that this information is redundant with what's in the
conformance lookup table already, so it will be going away soon.
Swift SVN r31334
This is a step toward weeding out the "getProtocols()" list on
TypeDecl. Now, use the Archetype's list of protocols for the set of
protocols to which the type parameter or associated type
conforms. Since that list is fully canonicalized, it's more generally
reliable. However, start serializing the list of inherited types for a
generic type parameter, so we can print it appropriately.
Swift SVN r31297
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
the regressions that r31105 introduced in the validation tests, as well as fixing a number
of other validation tests as well.
Introduce a new UnresolvedType to the type system, and have CSDiags start to use it
as a way to get more type information out of incorrect subexpressions. UnresolvedType
generally just propagates around the type system like a type variable:
- it magically conforms to all protocols
- it CSGens as an unconstrained type variable.
- it ASTPrints as _, just like a type variable.
The major difference is that UnresolvedType can be used outside the context of a
ConstraintSystem, which is useful for CSGen since it sets up several of them to
diagnose subexpressions w.r.t. their types.
For now, our use of this is extremely limited: when a closureexpr has no contextual
type available and its parameters are invalid, we wipe them out with UnresolvedType
(instead of the previous nulltype dance) to get ambiguities later on.
We also introduce a new FreeTypeVariableBinding::UnresolvedType approach for
constraint solving (and use this only in one place in CSDiags so far, to resolve
the callee of a CallExpr) which solves a system and rewrites any leftover type
variables as UnresolvedTypes. This allows us to get more precise information out,
for example, diagnosing:
func r22162441(lines: [String]) {
lines.map { line in line.fooBar() }
}
with: value of type 'String' has no member 'fooBar'
instead of: type of expression is ambiguous without more context
This improves a number of other diagnostics as well, but is just the infrastructural
stepping stone for greater things.
Swift SVN r31130
as a way to get more type information out of incorrect subexpressions. UnresolvedType
generally just propagates around the type system like a type variable:
- it magically conforms to all protocols
- it CSGens as an unconstrained type variable.
- it ASTPrints as _, just like a type variable.
The major difference is that UnresolvedType can be used outside the context of a
ConstraintSystem, which is useful for CSGen since it sets up several of them to
diagnose subexpressions w.r.t. their types.
For now, our use of this is extremely limited: when a closureexpr has no contextual
type available and its parameters are invalid, we wipe them out with UnresolvedType
(instead of the previous nulltype dance) to get ambiguities later on.
We also introduce a new FreeTypeVariableBinding::UnresolvedType approach for
constraint solving (and use this only in one place in CSDiags so far, to resolve
the callee of a CallExpr) which solves a system and rewrites any leftover type
variables as UnresolvedTypes. This allows us to get more precise information out,
for example, diagnosing:
func r22162441(lines: [String]) {
lines.map { line in line.fooBar() }
}
with: value of type 'String' has no member 'fooBar'
instead of: type of expression is ambiguous without more context
This improves a number of other diagnostics as well, but is just the infrastructural
stepping stone for greater things.
Swift SVN r31105
This is mostly a "don't crash" commit, but since member XREFs don't
specify which module they're looking in, they can actually pick up
members from the module currently being compiled...which may not have
a type yet.
rdar://problem/21071045
Swift SVN r30895