backend, runtime: place vtable at the end of TypeInfo

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/descriptors/DescriptorUtils.kt

@@ -170,6 +170,8 @@ internal val ClassDescriptor.сontributedMethods: List<FunctionDescriptor>
         return allMethods
     }
 
+fun ClassDescriptor.isAbstract() = this.modality == Modality.SEALED || this.modality == Modality.ABSTRACT
+
 // TODO: optimize
 val ClassDescriptor.vtableEntries: List<FunctionDescriptor>
     get() {
@@ -190,6 +192,9 @@ val ClassDescriptor.vtableEntries: List<FunctionDescriptor>
         return inheritedVtableSlots + (methods - inheritedVtableSlots).filter { it.isOverridable }
     }
 
+val ClassDescriptor.vtableSize: Int
+    get() = if (this.isAbstract()) 0 else this.vtableEntries.size
+
 fun ClassDescriptor.vtableIndex(function: FunctionDescriptor): Int {
     this.vtableEntries.forEachIndexed { index, functionDescriptor ->
         if (functionDescriptor == function.original) return index
@@ -199,7 +204,7 @@ fun ClassDescriptor.vtableIndex(function: FunctionDescriptor): Int {
 
 val ClassDescriptor.methodTableEntries: List<FunctionDescriptor>
     get() {
-        assert (this.modality != Modality.ABSTRACT)
+        assert (!this.isAbstract())
 
         return this.сontributedMethods.filter { it.isOverridableOrOverrides }
         // TODO: probably method table should contain all accessible methods to improve binary compatibility

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/ContextUtils.kt

@@ -7,6 +7,7 @@ import org.jetbrains.kotlin.backend.konan.Distribution
 import org.jetbrains.kotlin.backend.konan.hash.GlobalHash
 import org.jetbrains.kotlin.backend.konan.KonanConfigKeys
 import org.jetbrains.kotlin.backend.konan.descriptors.backingField
+import org.jetbrains.kotlin.backend.konan.descriptors.vtableSize
 import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import org.jetbrains.kotlin.descriptors.FunctionDescriptor
 import org.jetbrains.kotlin.descriptors.PropertyDescriptor
@@ -114,22 +115,24 @@ internal interface ContextUtils {
             return constValue(result)
         }
 
+    /**
+     * Pointer to struct { TypeInfo, vtable }.
+     */
+    val ClassDescriptor.typeInfoWithVtable: ConstPointer
+        get() {
+            val type = structType(runtime.typeInfoType, LLVMArrayType(int8TypePtr, this.vtableSize)!!)
+            return constPointer(externalGlobal(this.typeInfoSymbolName, type))
+        }
+
+    val ClassDescriptor.typeInfoPtr: ConstPointer
+        get() = typeInfoWithVtable.getElementPtr(0)
+
     /**
      * Pointer to type info for given class.
      * It may be declared as pointer to external variable.
      */
     val ClassDescriptor.llvmTypeInfoPtr: LLVMValueRef
-        get() {
-            val module = context.llvmModule
-            val globalName = this.typeInfoSymbolName
-            val globalPtr = LLVMGetNamedGlobal(module, globalName) ?:
-                            LLVMAddGlobal(module, runtime.typeInfoType, globalName)!!
-
-            return globalPtr
-        }
-
-    val ClassDescriptor.typeInfoPtr: ConstPointer
-        get() = constPointer(this.llvmTypeInfoPtr)
+        get() = typeInfoPtr.llvm
 
     /**
      * Pointer to type info for this type, or `null` if the type doesn't have corresponding type info.

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/IrToBitcode.kt

@@ -1786,15 +1786,16 @@ internal class CodeGeneratorVisitor(val context: Context) : IrElementVisitorVoid
     fun callVirtual(descriptor: FunctionDescriptor, args: List<LLVMValueRef>): LLVMValueRef {
         val typeInfoPtrPtr  = LLVMBuildStructGEP(codegen.builder, args[0], 0 /* type_info */, "")!!
         val typeInfoPtr     = codegen.load(typeInfoPtrPtr)
+        assert (typeInfoPtr.type == codegen.kTypeInfoPtr)
 
         val owner = descriptor.containingDeclaration as ClassDescriptor
         val llvmMethod = if (!owner.isInterface) {
             // If this is a virtual method of the class - we can call via vtable.
             val index = owner.vtableIndex(descriptor)
-            val vtablePtr = LLVMBuildStructGEP(codegen.builder, typeInfoPtr, 7 /* vtable */, "")!!
-            val vtable = codegen.load(vtablePtr)
-            // TODO: those two loads are bad, we shall rework vtable to follow TypeInfo in memory, so
-            //       this code shall just take end address of TypeInfo and use numbered slot from there.
+
+            val vtablePlace = codegen.gep(typeInfoPtr, Int32(1).llvm) // typeInfoPtr + 1
+            val vtable = codegen.bitcast(kInt8PtrPtr, vtablePlace)
+
             val slot = codegen.gep(vtable, Int32(index).llvm)
             codegen.load(slot)
         } else {

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/RTTIGenerator.kt

@@ -4,11 +4,7 @@ package org.jetbrains.kotlin.backend.konan.llvm
 import kotlinx.cinterop.*
 import llvm.*
 import org.jetbrains.kotlin.backend.konan.Context
-import org.jetbrains.kotlin.backend.konan.descriptors.methodTableEntries
-import org.jetbrains.kotlin.backend.konan.descriptors.vtableEntries
-import org.jetbrains.kotlin.backend.konan.descriptors.implementation
-import org.jetbrains.kotlin.backend.konan.descriptors.implementedInterfaces
-import org.jetbrains.kotlin.backend.konan.descriptors.isInterface
+import org.jetbrains.kotlin.backend.konan.descriptors.*
 import org.jetbrains.kotlin.builtins.KotlinBuiltIns
 import org.jetbrains.kotlin.descriptors.*
 import org.jetbrains.kotlin.name.FqName
@@ -31,7 +27,6 @@ internal class RTTIGenerator(override val context: Context) : ContextUtils {
                                  val objOffsetsCount: Int,
                                  val interfaces: ConstValue,
                                  val interfacesCount: Int,
-                                 val vtable: ConstValue,
                                  val methods: ConstValue,
                                  val methodsCount: Int,
                                  val fields: ConstValue,
@@ -50,8 +45,6 @@ internal class RTTIGenerator(override val context: Context) : ContextUtils {
                     interfaces,
                     Int32(interfacesCount),
 
-                    vtable,
-
                     methods,
                     Int32(methodsCount),
 
@@ -141,12 +134,12 @@ internal class RTTIGenerator(override val context: Context) : ContextUtils {
         val fieldsPtr = staticData.placeGlobalConstArray("kfields:$className",
                 runtime.fieldTableRecordType, fields)
 
-        val vtable: List<ConstValue>
+        val vtableEntries: List<ConstValue>
         val methods: List<ConstValue>
 
-        if (classDesc.modality != Modality.ABSTRACT) {
+        if (!classDesc.isAbstract()) {
             // TODO: compile-time resolution limits binary compatibility
-            vtable = classDesc.vtableEntries.map { it.implementation.entryPointAddress }
+            vtableEntries = classDesc.vtableEntries.map { it.implementation.entryPointAddress }
 
             methods = classDesc.methodTableEntries.map {
                 val nameSignature = it.functionName.localHash
@@ -155,12 +148,13 @@ internal class RTTIGenerator(override val context: Context) : ContextUtils {
                 MethodTableRecord(nameSignature, methodEntryPoint)
             }.sortedBy { it.nameSignature.value }
         } else {
-            vtable = emptyList()
+            vtableEntries = emptyList()
             methods = emptyList()
         }
 
+        assert (vtableEntries.size == classDesc.vtableSize)
 
-        val vtablePtr = staticData.placeGlobalConstArray("kvtable:$className", pointerType(int8Type), vtable)
+        val vtable = ConstArray(int8TypePtr, vtableEntries)
 
         val methodsPtr = staticData.placeGlobalConstArray("kmethods:$className",
                 runtime.methodTableRecordType, methods)
@@ -169,15 +163,14 @@ internal class RTTIGenerator(override val context: Context) : ContextUtils {
                 superType,
                 objOffsetsPtr, objOffsets.size,
                 interfacesPtr, interfaces.size,
-                vtablePtr,
                 methodsPtr, methods.size,
                 fieldsPtr, if (classDesc.isInterface) -1 else fields.size)
 
-        val typeInfoGlobal = classDesc.llvmTypeInfoPtr // TODO: it is a hack
-        LLVMSetInitializer(typeInfoGlobal, typeInfo.llvm)
+        val typeInfoGlobal = classDesc.typeInfoWithVtable.llvm // TODO: it is a hack
+        LLVMSetInitializer(typeInfoGlobal, Struct(typeInfo, vtable).llvm)
         LLVMSetGlobalConstant(typeInfoGlobal, 1)
 
-        exportTypeInfoIfRequired(classDesc, typeInfoGlobal)
+        exportTypeInfoIfRequired(classDesc, classDesc.llvmTypeInfoPtr)
     }
 
 }

runtime/src/main/cpp/TypeInfo.h

@@ -34,14 +34,14 @@ struct TypeInfo {
     const TypeInfo* const* implementedInterfaces_;
     int32_t implementedInterfacesCount_;
     // Null for abstract classes and interfaces.
-    // TODO: place vtable at the end of TypeInfo to eliminate the indirection.
-    void* const* vtable_;
-    // Null for abstract classes and interfaces.
     const MethodTableRecord* openMethods_;
     uint32_t openMethodsCount_;
     const FieldTableRecord* fields_;
     // Is negative to mark an interface.
     int32_t fieldsCount_;
+
+    // vtable starts just after declared contents of the TypeInfo:
+    // void* const vtable_[];
 };
 
 #ifdef __cplusplus