Add extraction protocol conformance descriptor extraction, as read from an object file image, to TypeRefBuilder.

Author: artemcm

include/swift/ABI/Metadata.h

@@ -79,6 +79,16 @@ struct RuntimeTarget<4> {
   using StoredSize = uint32_t;
   using StoredPointerDifference = int32_t;
   static constexpr size_t PointerSize = 4;
+
+#if SWIFT_OBJC_INTEROP
+  static constexpr bool ObjCInterop = true;
+  template <typename T>
+  using TargetAnyClassMetadata = TargetAnyClassMetadataObjCInterop<T>;
+#else
+  static constexpr bool ObjCInterop = false;
+  template <typename T>
+  using TargetAnyClassMetadata = TargetAnyClassMetadata<T>;
+#endif
 };
 
 template <>
@@ -91,6 +101,16 @@ struct RuntimeTarget<8> {
   using StoredSize = uint64_t;
   using StoredPointerDifference = int64_t;
   static constexpr size_t PointerSize = 8;
+
+#if SWIFT_OBJC_INTEROP
+  static constexpr bool ObjCInterop = true;
+  template <typename T>
+  using TargetAnyClassMetadata = TargetAnyClassMetadataObjCInterop<T>;
+#else
+  static constexpr bool ObjCInterop = false;
+  template <typename T>
+  using TargetAnyClassMetadata = TargetAnyClassMetadata<T>;
+#endif
 };
 
 namespace reflection {
@@ -540,6 +560,14 @@ namespace {
 
 using TypeContextDescriptor = TargetTypeContextDescriptor<InProcess>;
 
+template<unsigned PointerSize>
+using ExternalTypeContextDescriptor
+#if SWIFT_OBJC_INTEROP
+= TargetTypeContextDescriptor<External<WithObjCInterop<RuntimeTarget<PointerSize>>>>;
+#else
+= TargetTypeContextDescriptor<External<NoObjCInterop<RuntimeTarget<PointerSize>>>>;
+#endif
+
 // FIXME: https://bugs.swift.org/browse/SR-1155
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Winvalid-offsetof"
@@ -2106,7 +2134,15 @@ using ProtocolRequirement = TargetProtocolRequirement<InProcess>;
 
 template<typename Runtime> struct TargetProtocolDescriptor;
 using ProtocolDescriptor = TargetProtocolDescriptor<InProcess>;
-  
+
+template<unsigned PointerSize>
+using ExternalProtocolDescriptor
+#if SWIFT_OBJC_INTEROP
+= TargetProtocolDescriptor<External<WithObjCInterop<RuntimeTarget<PointerSize>>>>;
+#else
+= TargetProtocolDescriptor<External<NoObjCInterop<RuntimeTarget<PointerSize>>>>;
+#endif
+
 /// A witness table for a protocol.
 ///
 /// With the exception of the initial protocol conformance descriptor,
@@ -2722,6 +2758,16 @@ struct TargetProtocolConformanceDescriptor final
     return TypeRef.getTypeDescriptor(getTypeKind());
   }
 
+  constexpr inline auto
+  getTypeDescriptorOffset() const -> typename Runtime::StoredSize {
+    return offsetof(typename std::remove_reference<decltype(*this)>::type, TypeRef);
+  }
+
+  constexpr inline auto
+  getProtocolDescriptorOffset() const -> typename Runtime::StoredSize {
+    return offsetof(typename std::remove_reference<decltype(*this)>::type, Protocol);
+  }
+
   TargetContextDescriptor<Runtime> * __ptrauth_swift_type_descriptor *
   _getTypeDescriptorLocation() const {
     if (getTypeKind() != TypeReferenceKind::IndirectTypeDescriptor)
@@ -2840,9 +2886,21 @@ using TargetProtocolConformanceRecord =
 
 using ProtocolConformanceRecord = TargetProtocolConformanceRecord<InProcess>;
 
+template<unsigned PointerSize>
 using ExternalProtocolConformanceDescriptor
-  = TargetProtocolConformanceDescriptor<External<RuntimeTarget<8>>>;
-using ExternalProtocolConformanceRecord = TargetProtocolConformanceRecord<External<RuntimeTarget<8>>>;
+#if SWIFT_OBJC_INTEROP
+= TargetProtocolConformanceDescriptor<External<WithObjCInterop<RuntimeTarget<PointerSize>>>>;
+#else
+= TargetProtocolConformanceDescriptor<External<NoObjCInterop<RuntimeTarget<PointerSize>>>>;
+#endif
+
+template<unsigned PointerSize>
+using ExternalProtocolConformanceRecord
+#if SWIFT_OBJC_INTEROP
+= TargetProtocolConformanceRecord<External<WithObjCInterop<RuntimeTarget<PointerSize>>>>;
+#else
+= TargetProtocolConformanceRecord<External<NoObjCInterop<RuntimeTarget<PointerSize>>>>;
+#endif
 
 template<typename Runtime>
 struct TargetGenericContext;
@@ -2893,6 +2951,13 @@ struct TargetContextDescriptor {
 };
 
 using ContextDescriptor = TargetContextDescriptor<InProcess>;
+template<unsigned PointerSize>
+using ExternalContextDescriptor
+#if SWIFT_OBJC_INTEROP
+= TargetContextDescriptor<External<WithObjCInterop<RuntimeTarget<PointerSize>>>>;
+#else
+= TargetContextDescriptor<External<NoObjCInterop<RuntimeTarget<PointerSize>>>>;
+#endif
 
 inline bool isCImportedModuleName(llvm::StringRef name) {
   // This does not include MANGLING_MODULE_CLANG_IMPORTER because that's
@@ -3417,6 +3482,11 @@ struct TargetProtocolDescriptor final
             NumRequirements};
   }
 
+  constexpr inline auto
+  getNameOffset() const -> typename Runtime::StoredSize {
+    return offsetof(typename std::remove_reference<decltype(*this)>::type, Name);
+  }
+
   /// Retrieve the requirement base descriptor address.
   ConstTargetPointer<Runtime, TargetProtocolRequirement<Runtime>>
   getRequirementBaseDescriptor() const {
@@ -4081,6 +4151,11 @@ class TargetTypeContextDescriptor
   /// type's metadata. The returned value is measured in sizeof(StoredPointer).
   int32_t getGenericArgumentOffset() const;
 
+  constexpr inline auto
+  getNameOffset() const -> typename Runtime::StoredSize {
+    return offsetof(typename std::remove_reference<decltype(*this)>::type, Name);
+  }
+
   /// Return the start of the generic arguments array in the nominal
   /// type's metadata. The returned value is measured in sizeof(StoredPointer).
   const TargetMetadata<Runtime> * const *getGenericArguments(

include/swift/ABI/ObjectFile.h

@@ -12,15 +12,16 @@
 
 namespace swift {
 
-/// Represents the seven reflection sections used by Swift
+/// Represents the eight reflection sections used by Swift
 enum ReflectionSectionKind : uint8_t {
   fieldmd,
   assocty,
   builtin,
   capture,
   typeref,
   reflstr,
-  conform
+  conform,
+  protocs
 };
 
 /// Abstract base class responsible for providing the correct reflection section
@@ -50,6 +51,8 @@ class SwiftObjectFileFormatMachO : public SwiftObjectFileFormat {
       return "__swift5_reflstr";
     case conform:
       return "__swift5_proto";
+    case protocs:
+      return "__swift5_protos";
     }
     llvm_unreachable("Section type not found.");
   }
@@ -73,7 +76,9 @@ class SwiftObjectFileFormatELF : public SwiftObjectFileFormat {
     case reflstr:
       return "swift5_reflstr";
     case conform:
-      return "swift5_proto";
+      return "swift5_protocol_conformances";
+    case protocs:
+      return "swift5_protocols";
     }
     llvm_unreachable("Section type not found.");
   }
@@ -97,7 +102,9 @@ class SwiftObjectFileFormatCOFF : public SwiftObjectFileFormat {
     case reflstr:
       return ".sw5rfst";
     case conform:
-      return ".sw5cnfrm"; // TODO: Figure out the real name
+      return ".sw5prtc$B";
+    case protocs:
+      return ".sw5prt$B";
     }
     llvm_unreachable("Section  not found.");
   }

include/swift/Basic/RelativePointer.h

@@ -442,6 +442,17 @@ class RelativeDirectPointerImpl {
     return reinterpret_cast<PointerTy>(absolute);
   }
 
+  /// Apply the offset to a parameter, instead of `this`.
+  PointerTy getRelative(void *base) const & {
+    // Check for null.
+    if (Nullable && RelativeOffset == 0)
+      return nullptr;
+
+    // The value is addressed relative to `base`.
+    uintptr_t absolute = detail::applyRelativeOffset(base, RelativeOffset);
+    return reinterpret_cast<PointerTy>(absolute);
+  }
+
   /// A zero relative offset encodes a null reference.
   bool isNull() const & {
     return RelativeOffset == 0;
@@ -476,6 +487,10 @@ class RelativeDirectPointer<T, Nullable, Offset,
     return this->get();
   }
 
+  const typename super::ValueTy* getRelative(void *base) const & {
+    return this->super::getRelative(base);
+  }
+
   using super::isNull;
 };
 

include/swift/Reflection/ReflectionContext.h

@@ -221,6 +221,22 @@ class ReflectionContext
             SectionsBuf + (I * sizeof(typename T::Section)));
         if (strncmp(S->sectname, Name.data(), strlen(Name.data())) != 0)
           continue;
+
+        // The above check verifies that `Name` is a prefix to the examined
+        // section name, to allow for matching of sections with a suffix
+        // like `_TEXT`, etc.
+        // "__swift5_proto" section name is a substring of "__swift5_protos",
+        // Ensure we don't return the latter when looking for the former.
+        SwiftObjectFileFormatMachO ObjectFileFormat;
+        if (Name.data() ==
+            ObjectFileFormat.getSectionName(ReflectionSectionKind::conform)) {
+          auto protocolsSectionName =
+              ObjectFileFormat.getSectionName(ReflectionSectionKind::protocs);
+          if (strncmp(S->sectname, protocolsSectionName.data(),
+                      strlen(protocolsSectionName.data())) == 0)
+            continue;
+        }
+
         auto RemoteSecStart = S->addr + Slide;
         auto LocalSectBuf =
             this->getReader().readBytes(RemoteAddress(RemoteSecStart), S->size);