properties are represented as rvalues, not non-mutable lvalues. As part of
this, isReferencedAsLValue() only returns true for mutable VarDecls.
This required some pretty serious rearrangement and refactoring of code,
because now (among other things) get-only properties can be emitted as rvalues,
so the rvalue machinery needs to be able to produce getter calls.
This is an important step towards getting proper value semantics going (for
'let's etc) and also allows us to materialize addresses less often. As a
simple example, before we would silgen this:
struct S {
var i : Int
}
var P : S { get: ... }
func f() {
print(P.i)
}
into:
%2 = function_ref @_TF1tg1PVS_1S : $@thin () -> S // user: %3
%3 = apply %2() : $@thin () -> S // user: %5
%4 = alloc_stack $S // users: %9, %6, %5
store %3 to %4#1 : $*S // id: %5
%6 = struct_element_addr %4#1 : $*S, #i // user: %7
%7 = load %6 : $*Int64 // user: %8
now we generate:
%2 = function_ref @_TF1tg1PVS_1S : $@thin () -> S // user: %3
%3 = apply %2() : $@thin () -> S // user: %4
%4 = struct_extract %3 : $S, #i // user: %5
Swift SVN r11632
struct rvalue, to produce a struct element directly, without converting the rvalue
to an lvalue.
This means that it no longer materializes an lvalue when applied to a let declaration
or other rvalue. For example, this testcase:
struct X { var a,b : Int}
func g() -> X { return X(1,2) }
func f() {
let a = g().a
}
used to sema into:
(load_expr implicit type='Int'
(member_ref_expr type='@inout (implicit, nonsettable)Int' decl=t.(file).X.a@t.swift:2:16
(materialize_expr implicit type='@inout (implicit)X'
(call_expr type='X'
and silgen into:
%1 = function_ref @_TF1t1gFT_VS_1X : $@thin () -> X // user: %2
%2 = apply %1() : $@thin () -> X // user: %4
%3 = alloc_stack $X // users: %7, %5, %4
store %2 to %3#1 : $*X // id: %4
%5 = struct_element_addr %3#1 : $*X, #a // user: %6
%6 = load %5 : $*Int64
It now sema's into:
(member_ref_expr type='Int' decl=t.(file).X.a@t.swift:1:16
(call_expr type='X'
and silgens into:
%1 = function_ref @_TF1t1gFT_VS_1X : $@thin () -> X // user: %2
%2 = apply %1() : $@thin () -> X // user: %3
%3 = struct_extract %2 : $X, #a
I think I'm finally starting to grok Doug's crazy typechecker magic.
Swift SVN r11599
(various) FunctionType::get's, ArrayType::get,
ArraySliceType::get, OptionalType::get, and a few
other places.
There is more to be done here, but this is all I plan to do
for now.
Swift SVN r11497
This completes the FileUnit refactoring. A module consists of multiple
FileUnits, which provide decls from various file-like sources. I say
"file-like" because the Builtin module is implemented with a single
BuiltinUnit, and imported Clang modules are just a single FileUnit source
within a module.
Most modules, therefore, contain a single file unit; only the main module
will contain multiple source files (and eventually partial AST files).
The term "translation unit" has been scrubbed from the project. To refer
to the context of declarations outside of any other declarations, use
"top-level" or "module scope". To refer to a .swift file or its DeclContext,
use "source file". To refer to a single unit of compilation, use "module",
since the model is that an entire module will be compiled with a single
driver call. (It will still be possible to compile a single source file
through the direct-to-frontend interface, but only in the context of the
whole module.)
Swift SVN r10837
Part of the FileUnit restructuring. A serialized module is now represented as
a TranslationUnit containing a single SerializedASTFile.
As part of this change, the FileUnit interface has been made virtual, rather
than switching on the Kind in every accessor. We think the operations
performed on files are sufficiently high-level that this shouldn't affect us.
A nice side effect of all this is that we now properly model the visibility
of modules imported into source files. Previously, we would always consider
the top-level imports of all files within a target, whether re-exported or
not.
We may still end up wanting to distinguish properties of a complete Swift
module file from a partial AST file, but we can do that within
SerializedModuleLoader.
Swift SVN r10832
Instead of cutting corners by emitting a static property reference as a DeclRef, do the right thing and build a MemberRef on the metatype. Add the smarts to SILGen to recognize static property MemberRefs and emit global_addr instructions for (nongeneric, nondynamic) static properties.
Swift SVN r10482
Instead of hardcoding Builtin.Word to be an alias for Builtin.Int64, make it its own type of abstract pointer width.
- Change BuiltinIntegerType's width representation to accommodate abstract widths.
- In the AST and in SIL, store values of the types as the greatest supported size for the abstract width (64 bits for a pointer).
- Add some type safety to the ([sz]ext|trunc)(OrBitCast)? builtins that they're used appropriately given the upper and lower bounds of the abstract sizes they're working with.
- Now that Builtin.Word is a distinct type, give it its own mangling.
- In IRGen, lower pointer-sized BuiltinIntegerType appropriately for the target, and truncate lowered SIL values if necessary.
Fixes <rdar://problem/15367913>.
Swift SVN r10467
Build the getter and setter of a static property as static func decls, and add a verifier check that the static-ness of a var and its accessors match up.
Swift SVN r10395
Introduced VarDecl::getTypeSourceRangeForDiagnostics(), which is not precise
right now; it just highlights the type source range of the typed pattern.
Filed rdar://15441111 to improve it in future.
Swift SVN r10344
implicit, we should not verify source locations with this patch.
LLDB creates ASTs that contain some pieces of AST that came from the parser,
and some other pieces that were synthesized. AST Verifier complains about this
strange mix while checking source ranges.
rdar://15320934
Swift SVN r9819
And, properly treat imports as per-file: when looking up decls through the
TU module, don't pick up every other source file's imports.
This implements our resolution rules:
1. Check the current source file.
2. Check the current module.
3. Check imported modules.
Currently, "import Foo" is treated as a file-private import and
"@reexported import Foo" is treated as a public /and/ module-wide import.
This further suggests that access control is the right tool for re-export
control:
(private) import Foo // current file only
package import Foo // whole module
public import Foo // whole world
Swift SVN r9682
Value witness markers note the location within a generic function
type's list of requirements where the value witness table will be
placed when calling a generic function with that type. It allows one
to get the same effect from walking the requirements of a generic
function that one would get from walking all levels of a
GenericParamList, with all archetypes of each generic parameter list,
along with all of the protocols to which each archetype conforms,
which SILGen and IRGen both do.
AST verification ensures that the property above holds; we're not
making use of it just yet.
Swift SVN r9509
The list of requirements within a generic function type is
functionally identical to the list of conformances in the list of "all
archetypes" that a given function carries. Synchronize these lists so
they have identical requirements in the same order, which allows us to
substitute the former for the latter.
Swift SVN r9472
Now that we have a solid Optional-based story for dynamic casts, it's no longer needed, and can be expressed as '(x as T)!'. Future refinement of the 'as' syntax will deal with the unfortunate extra parens.
Swift SVN r9181
As with the monadic '?', we treat any left-bound '!' as a postfix
operator. Currently, it extracts the value of its optional
subexpression, failing at run-time if the optional is empty.
Swift SVN r8948