averello/swift-mirror
1
0
Fork 0
mirror of https://github.com/apple/swift.git synced 2025-12-21 12:14:44 +01:00
Code Issues Packages Projects Releases Wiki Activity

Make 'T.self is U.Type' work.

Browse Source 
Fix up all of type-checking, SILGen, IRGen, and the runtime to support checked casts of metatypes. <rdar://problem/16847453>

Swift SVN r17719
This commit is contained in:
Joe Groff
2014-05-08 22:55:14 +00:00
parent f18dbbe9e8
commit 1dce36edd2
11 changed files with 320 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

130
stdlib/runtime/Metadata.cpp
View File

@@ -15,6 +15,7 @@
//===----------------------------------------------------------------------===//
#include "llvm/Support/MathExtras.h"
#include "swift/Basic/Fallthrough.h"
#include "swift/Basic/LLVM.h"
#include "swift/Basic/Range.h"
#include "swift/Runtime/HeapObject.h"
@@ -407,6 +408,135 @@ swift::swift_dynamicCastUnconditional(const void *object,
return swift_dynamicCastClassUnconditional(object, targetClassType);
}
const Metadata *
swift::swift_dynamicCastMetatype(const Metadata *sourceType,
const Metadata *targetType) {
auto origSourceType = sourceType;
switch (targetType->getKind()) {
case MetadataKind::ObjCClassWrapper:
// Get the actual class object.
targetType = static_cast<const ObjCClassWrapperMetadata*>(targetType)
->Class;
SWIFT_FALLTHROUGH;
case MetadataKind::Class:
// The source value must also be a class; otherwise the cast fails.
switch (sourceType->getKind()) {
case MetadataKind::ObjCClassWrapper:
// Get the actual class object.
sourceType = static_cast<const ObjCClassWrapperMetadata*>(sourceType)
->Class;
SWIFT_FALLTHROUGH;
case MetadataKind::Class: {
// Check if the source is a subclass of the target.
// We go through ObjC lookup to deal with potential runtime magic in ObjC
// land.
if (swift_dynamicCastObjCClassMetatype((const ClassMetadata*)sourceType,
(const ClassMetadata*)targetType))
return origSourceType;
return nullptr;
}
case MetadataKind::ForeignClass: // FIXME
case MetadataKind::Existential:
case MetadataKind::ExistentialMetatype:
case MetadataKind::Function:
case MetadataKind::HeapArray:
case MetadataKind::HeapLocalVariable:
case MetadataKind::Metatype:
case MetadataKind::Enum:
case MetadataKind::Opaque:
case MetadataKind::PolyFunction:
case MetadataKind::Struct:
case MetadataKind::Tuple:
return nullptr;
}
break;
case MetadataKind::ForeignClass: // FIXME
case MetadataKind::Existential:
case MetadataKind::ExistentialMetatype:
case MetadataKind::Function:
case MetadataKind::HeapArray:
case MetadataKind::HeapLocalVariable:
case MetadataKind::Metatype:
case MetadataKind::Enum:
case MetadataKind::Opaque:
case MetadataKind::PolyFunction:
case MetadataKind::Struct:
case MetadataKind::Tuple:
// The cast succeeds only if the metadata pointers are statically
// equivalent.
if (sourceType != targetType)
return nullptr;
return origSourceType;
}
}
const Metadata *
swift::swift_dynamicCastMetatypeUnconditional(const Metadata *sourceType,
const Metadata *targetType) {
auto origSourceType = sourceType;
switch (targetType->getKind()) {
case MetadataKind::ObjCClassWrapper:
// Get the actual class object.
targetType = static_cast<const ObjCClassWrapperMetadata*>(targetType)
->Class;
SWIFT_FALLTHROUGH;
case MetadataKind::Class:
// The source value must also be a class; otherwise the cast fails.
switch (sourceType->getKind()) {
case MetadataKind::ObjCClassWrapper:
// Get the actual class object.
sourceType = static_cast<const ObjCClassWrapperMetadata*>(sourceType)
->Class;
SWIFT_FALLTHROUGH;
case MetadataKind::Class: {
// Check if the source is a subclass of the target.
// We go through ObjC lookup to deal with potential runtime magic in ObjC
// land.
swift_dynamicCastObjCClassMetatypeUnconditional(
(const ClassMetadata*)sourceType,
(const ClassMetadata*)targetType);
// If we returned, then the cast succeeded.
return origSourceType;
}
case MetadataKind::ForeignClass: // FIXME
case MetadataKind::Existential:
case MetadataKind::ExistentialMetatype:
case MetadataKind::Function:
case MetadataKind::HeapArray:
case MetadataKind::HeapLocalVariable:
case MetadataKind::Metatype:
case MetadataKind::Enum:
case MetadataKind::Opaque:
case MetadataKind::PolyFunction:
case MetadataKind::Struct:
case MetadataKind::Tuple:
swift::crash("Swift dynamic cast failed");
}
break;
case MetadataKind::ForeignClass: // FIXME
case MetadataKind::Existential:
case MetadataKind::ExistentialMetatype:
case MetadataKind::Function:
case MetadataKind::HeapArray:
case MetadataKind::HeapLocalVariable:
case MetadataKind::Metatype:
case MetadataKind::Enum:
case MetadataKind::Opaque:
case MetadataKind::PolyFunction:
case MetadataKind::Struct:
case MetadataKind::Tuple:
// The cast succeeds only if the metadata pointers are statically
// equivalent.
if (sourceType != targetType)
swift::crash("Swift dynamic cast failed");
return origSourceType;
}
}
const OpaqueValue *
swift::swift_dynamicCastIndirect(const OpaqueValue *value,
const Metadata *sourceType,