Move object method bodies into a separate class when original class is too large

bvm/ballerina-runtime/src/main/java/io/ballerina/runtime/internal/values/ErrorValue.java

@@ -74,6 +74,7 @@ public class ErrorValue extends BError implements RefValue {
     private final Object details;
 
     private static final String GENERATE_OBJECT_CLASS_PREFIX = "$value$";
+    private static final String SPLIT_CLASS_SUFFIX_REGEX = "\\$split\\$\\d";
     private static final String GENERATE_PKG_INIT = "___init_";
     private static final String GENERATE_PKG_START = "___start_";
     private static final String GENERATE_PKG_STOP = "___stop_";
@@ -441,7 +442,7 @@ private Optional<StackTraceElement> filterStackTraceElement(StackTraceElement st
     }
 
     private String cleanupClassName(String className) {
-        return className.replace(GENERATE_OBJECT_CLASS_PREFIX, "");
+        return className.replace(GENERATE_OBJECT_CLASS_PREFIX, "").replaceAll(SPLIT_CLASS_SUFFIX_REGEX, "");
     }
 
     private boolean isCompilerAddedName(String name) {

compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/compiler/bir/codegen/JvmCodeGenUtil.java

@@ -384,6 +384,11 @@ public static String getMethodDesc(List<BType> paramTypes, BType retType, BType
                 generateReturnType(retType);
     }
 
+    public static String getMethodDesc(List<BType> paramTypes, BType retType, String attachedTypeClassName) {
+        return INITIAL_METHOD_DESC + "L" + attachedTypeClassName + ";" + populateMethodDesc(paramTypes) +
+                generateReturnType(retType);
+    }
+
     public static String populateMethodDesc(List<BType> paramTypes) {
         StringBuilder descBuilder = new StringBuilder();
         for (BType type : paramTypes) {

compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/compiler/bir/codegen/JvmConstants.java

@@ -291,6 +291,7 @@ public class JvmConstants {
 
     // code generation related constants.
     public static final String MODULE_INIT_CLASS_NAME = "$_init";
+    public static final String OBJECT_SELF_INSTANCE = "self";
     public static final String UNION_TYPE_CONSTANT_CLASS_NAME = "constants/$_union_type_constants";
     public static final String ERROR_TYPE_CONSTANT_CLASS_NAME = "constants/$_error_type_constants";
     public static final String TUPLE_TYPE_CONSTANT_CLASS_NAME = "constants/$_tuple_type_constants";
@@ -380,6 +381,7 @@ public class JvmConstants {
     public static final String START_OF_HEADING_WITH_SEMICOLON = ":\u0001";
     public static final String CREATE_INTEROP_ERROR_METHOD = "createInteropError";
     public static final String LAMBDA_PREFIX = "$lambda$";
+    public static final String SPLIT_CLASS_SUFFIX = "$split$";
     public static final String POPULATE_METHOD_PREFIX = "$populate";
     public static final String ADD_METHOD = "add";
     public static final String TEST_EXECUTION_STATE = "__gH7W16nQmp0TestExecState__";
@@ -446,6 +448,7 @@ public class JvmConstants {
     public static final int MAX_CALLS_PER_CLIENT_METHOD = 100;
     public static final int MAX_CONSTANTS_PER_METHOD = 100;
     public static final int MAX_CALLS_PER_FUNCTION_CALL_METHOD = 100;
+    public static final int MAX_METHOD_COUNT_PER_BALLERINA_OBJECT = 100;
     /*
     MAX_STRINGS_PER_METHOD is calculated as below.
     No of instructions required for create ballerina string constant object = 12

compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/compiler/bir/codegen/JvmInstructionGen.java

@@ -156,6 +156,7 @@
 import static org.wso2.ballerinalang.compiler.bir.codegen.JvmConstants.MAP_VALUE;
 import static org.wso2.ballerinalang.compiler.bir.codegen.JvmConstants.MATH_UTILS;
 import static org.wso2.ballerinalang.compiler.bir.codegen.JvmConstants.MODULE_INIT_CLASS_NAME;
+import static org.wso2.ballerinalang.compiler.bir.codegen.JvmConstants.OBJECT_SELF_INSTANCE;
 import static org.wso2.ballerinalang.compiler.bir.codegen.JvmConstants.OBJECT_TYPE_IMPL;
 import static org.wso2.ballerinalang.compiler.bir.codegen.JvmConstants.REG_EXP_FACTORY;
 import static org.wso2.ballerinalang.compiler.bir.codegen.JvmConstants.SHORT_VALUE;
@@ -432,7 +433,7 @@ public void generateVarLoad(MethodVisitor mv, BIRNode.BIRVariableDcl varDcl, int
 
         switch (varDcl.kind) {
             case SELF:
-                mv.visitVarInsn(ALOAD, 0);
+                mv.visitVarInsn(ALOAD, this.indexMap.get(OBJECT_SELF_INSTANCE));
                 return;
             case CONSTANT:
             case GLOBAL:
@@ -1517,7 +1518,7 @@ void generateObjectStoreIns(BIRNonTerminator.FieldAccess objectStoreIns) {
             this.mv.visitTypeInsn(CHECKCAST, className);
             visitKeyValueExpressions(objectStoreIns);
             // invoke setOnInitialization() method
-            this.mv.visitMethodInsn(INVOKESPECIAL, className, "setOnInitialization",
+            this.mv.visitMethodInsn(INVOKEVIRTUAL, className, "setOnInitialization",
                     SET_ON_INIT, false);
             return;
         }

compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/compiler/bir/codegen/JvmPackageGen.java

@@ -243,7 +243,7 @@ private static void generateLockForVariable(ClassWriter cw) {
     private static void generateStaticInitializer(ClassWriter cw, String className, BIRPackage birPackage,
                                                   boolean isInitClass, boolean serviceEPAvailable,
                                                   AsyncDataCollector asyncDataCollector,
-                                                  JvmConstantsGen jvmConstantsGen, boolean isTestablePackage) {
+                                                  JvmConstantsGen jvmConstantsGen) {
         if (!isInitClass && asyncDataCollector.getStrandMetadata().isEmpty()) {
             return;
         }
@@ -432,7 +432,7 @@ private void generateModuleClasses(BIRPackage module, Map<String, byte[]> jarEnt
             }
             JvmCodeGenUtil.visitStrandMetadataFields(cw, asyncDataCollector.getStrandMetadata());
             generateStaticInitializer(cw, moduleClass, module, isInitClass, serviceEPAvailable,
-                    asyncDataCollector, jvmConstantsGen, isTestable);
+                    asyncDataCollector, jvmConstantsGen);
             cw.visitEnd();
 
             byte[] bytes = getBytes(cw, module);

compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/compiler/bir/codegen/JvmTerminatorGen.java

@@ -1274,7 +1274,6 @@ static String getStrandMetadataVarName(String typeName, String parentFunction) {
     }
 
     private void loadFpReturnType(BIROperand lhsOp) {
-
         BType futureType = JvmCodeGenUtil.getImpliedType(lhsOp.variableDcl.type);
         BType returnType = symbolTable.anyType;
         if (futureType.tag == TypeTags.FUTURE) {
@@ -1289,12 +1288,10 @@ private int getJVMIndexOfVarRef(BIRNode.BIRVariableDcl varDcl) {
     }
 
     private void loadVar(BIRNode.BIRVariableDcl varDcl) {
-
         jvmInstructionGen.generateVarLoad(this.mv, varDcl, this.getJVMIndexOfVarRef(varDcl));
     }
 
     private void storeToVar(BIRNode.BIRVariableDcl varDcl) {
-
         jvmInstructionGen.generateVarStore(this.mv, varDcl, this.getJVMIndexOfVarRef(varDcl));
     }
 

compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/compiler/bir/codegen/JvmValueGen.java

@@ -94,9 +94,11 @@
 import static org.wso2.ballerinalang.compiler.bir.codegen.JvmConstants.LOCK_VALUE;
 import static org.wso2.ballerinalang.compiler.bir.codegen.JvmConstants.MAP_VALUE;
 import static org.wso2.ballerinalang.compiler.bir.codegen.JvmConstants.MAP_VALUE_IMPL;
+import static org.wso2.ballerinalang.compiler.bir.codegen.JvmConstants.MAX_METHOD_COUNT_PER_BALLERINA_OBJECT;
 import static org.wso2.ballerinalang.compiler.bir.codegen.JvmConstants.OBJECT;
 import static org.wso2.ballerinalang.compiler.bir.codegen.JvmConstants.POPULATE_INITIAL_VALUES_METHOD;
 import static org.wso2.ballerinalang.compiler.bir.codegen.JvmConstants.RECORD_INIT_WRAPPER_NAME;
+import static org.wso2.ballerinalang.compiler.bir.codegen.JvmConstants.SPLIT_CLASS_SUFFIX;
 import static org.wso2.ballerinalang.compiler.bir.codegen.JvmConstants.STRAND_CLASS;
 import static org.wso2.ballerinalang.compiler.bir.codegen.JvmConstants.TYPEDESC_CLASS_PREFIX;
 import static org.wso2.ballerinalang.compiler.bir.codegen.JvmConstants.TYPEDESC_VALUE;
@@ -226,9 +228,8 @@ void generateValueClasses(Map<String, byte[]> jarEntries, JvmConstantsGen jvmCon
             if (optionalTypeDef.type.tag == TypeTags.OBJECT &&
                     Symbols.isFlagOn(optionalTypeDef.type.tsymbol.flags, Flags.CLASS)) {
                 BObjectType objectType = (BObjectType) optionalTypeDef.type;
-                byte[] bytes = this.createObjectValueClass(objectType, className, optionalTypeDef, jvmConstantsGen
-                        , asyncDataCollector);
-                jarEntries.put(className + ".class", bytes);
+                this.createObjectValueClasses(objectType, className, optionalTypeDef, jvmConstantsGen
+                        , asyncDataCollector, jarEntries);
             } else if (bType.tag == TypeTags.RECORD) {
                 BRecordType recordType = (BRecordType) bType;
                 byte[] bytes = this.createRecordValueClass(recordType, className, optionalTypeDef, jvmConstantsGen
@@ -591,8 +592,9 @@ private void createRecordPopulateInitialValuesMethod(ClassWriter cw, String clas
         mv.visitEnd();
     }
 
-    private byte[] createObjectValueClass(BObjectType objectType, String className, BIRNode.BIRTypeDefinition typeDef,
-                                          JvmConstantsGen jvmConstantsGen, AsyncDataCollector asyncDataCollector) {
+    private void createObjectValueClasses(BObjectType objectType, String className, BIRNode.BIRTypeDefinition typeDef,
+                                          JvmConstantsGen jvmConstantsGen, AsyncDataCollector asyncDataCollector,
+                                          Map<String, byte[]> jarEntries) {
         ClassWriter cw = new BallerinaClassWriter(COMPUTE_FRAMES);
         cw.visitSource(typeDef.pos.lineRange().fileName(), null);
 
@@ -607,8 +609,13 @@ private byte[] createObjectValueClass(BObjectType objectType, String className,
 
         List<BIRNode.BIRFunction> attachedFuncs = typeDef.attachedFuncs;
         if (attachedFuncs != null) {
-            this.createObjectMethods(cw, attachedFuncs, className, objectType, jvmTypeGen, jvmCastGen,
-                    jvmConstantsGen, asyncDataCollector);
+            if (attachedFuncs.size() > MAX_METHOD_COUNT_PER_BALLERINA_OBJECT) {
+                this.createObjectMethodsWithSplitClasses(cw, attachedFuncs, className, objectType, jvmTypeGen,
+                        jvmCastGen, jvmConstantsGen, asyncDataCollector, typeDef, jarEntries);
+            } else {
+                this.createObjectMethods(cw, attachedFuncs, className, objectType, jvmTypeGen, jvmCastGen,
+                        jvmConstantsGen, asyncDataCollector);
+            }
         }
 
         this.createObjectInit(cw, fields, className);
@@ -619,9 +626,8 @@ private byte[] createObjectValueClass(BObjectType objectType, String className,
         this.createLambdas(cw, asyncDataCollector, lambdaGen, className);
         JvmCodeGenUtil.visitStrandMetadataFields(cw, asyncDataCollector.getStrandMetadata());
         this.generateStaticInitializer(cw, className, module.packageID, asyncDataCollector);
-
         cw.visitEnd();
-        return jvmPackageGen.getBytes(cw, typeDef);
+        jarEntries.put(className + ".class", jvmPackageGen.getBytes(cw, typeDef));
     }
 
     private void createObjectFields(ClassWriter cw, Map<String, BField> fields) {
@@ -639,16 +645,66 @@ private void createObjectFields(ClassWriter cw, Map<String, BField> fields) {
         }
     }
 
-    private void createObjectMethods(ClassWriter cw, List<BIRNode.BIRFunction> attachedFuncs, String moduleClassName,
+    private void createObjectMethods(ClassWriter cw, List<BIRFunction> attachedFuncs, String moduleClassName,
                                      BObjectType currentObjectType, JvmTypeGen jvmTypeGen, JvmCastGen jvmCastGen,
                                      JvmConstantsGen jvmConstantsGen, AsyncDataCollector asyncDataCollector) {
 
         for (BIRNode.BIRFunction func : attachedFuncs) {
             if (func == null) {
                 continue;
             }
-            methodGen.generateMethod(func, cw, module, currentObjectType, moduleClassName,
-                    jvmTypeGen, jvmCastGen, jvmConstantsGen, asyncDataCollector);
+            methodGen.generateMethod(func, cw, module, currentObjectType, moduleClassName, jvmTypeGen, jvmCastGen,
+                    jvmConstantsGen, asyncDataCollector);
+        }
+    }
+
+    private void createObjectMethodsWithSplitClasses(ClassWriter cw, List<BIRFunction> attachedFuncs,
+                                                     String moduleClassName, BObjectType currentObjectType,
+                                                     JvmTypeGen jvmTypeGen, JvmCastGen jvmCastGen,
+                                                     JvmConstantsGen jvmConstantsGen,
+                                                     AsyncDataCollector asyncDataCollector,
+                                                     BIRNode.BIRTypeDefinition typeDef,
+                                                     Map<String, byte[]> jarEntries) {
+
+        int splitClassNum = 1;
+        ClassWriter splitCW = new BallerinaClassWriter(COMPUTE_FRAMES);
+        splitCW.visitSource(typeDef.pos.lineRange().fileName(), null);
+        String splitClassName = moduleClassName + SPLIT_CLASS_SUFFIX + splitClassNum;
+        splitCW.visit(V17, ACC_PUBLIC + ACC_SUPER, splitClassName, null, OBJECT, null);
+        JvmCodeGenUtil.generateDefaultConstructor(splitCW, OBJECT);
+        int methodCountPerSplitClass = 0;
+
+        for (BIRNode.BIRFunction func : attachedFuncs) {
+            if (func == null) {
+                continue;
+            }
+            if (func.name.value.contains("$init$")) {
+                methodGen.generateMethod(func, cw, module, currentObjectType, moduleClassName,
+                        jvmTypeGen, jvmCastGen, jvmConstantsGen, asyncDataCollector);
+                continue;
+            }
+            methodGen.genJMethodWithBObjectMethodCall(func, cw, module, jvmTypeGen, jvmCastGen, jvmConstantsGen,
+                    moduleClassName, asyncDataCollector, splitClassName);
+            methodGen.genJMethodForBFunc(func, splitCW, module, jvmTypeGen, jvmCastGen, jvmConstantsGen,
+                    moduleClassName, currentObjectType, asyncDataCollector, true);
+            methodCountPerSplitClass++;
+            if (methodCountPerSplitClass == MAX_METHOD_COUNT_PER_BALLERINA_OBJECT) {
+                splitCW.visitEnd();
+                byte[] splitBytes = jvmPackageGen.getBytes(splitCW, typeDef);
+                jarEntries.put(splitClassName + ".class", splitBytes);
+                splitClassNum++;
+                splitCW = new BallerinaClassWriter(COMPUTE_FRAMES);
+                splitCW.visitSource(typeDef.pos.lineRange().fileName(), null);
+                splitClassName = moduleClassName + SPLIT_CLASS_SUFFIX + splitClassNum;
+                splitCW.visit(V17, ACC_PUBLIC + ACC_SUPER, splitClassName, null, OBJECT, null);
+                JvmCodeGenUtil.generateDefaultConstructor(splitCW, OBJECT);
+                methodCountPerSplitClass = 0;
+            }
+        }
+        if (methodCountPerSplitClass != 0) {
+            splitCW.visitEnd();
+            byte[] splitBytes = jvmPackageGen.getBytes(splitCW, typeDef);
+            jarEntries.put(splitClassName + ".class", splitBytes);
         }
     }
 

compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/compiler/bir/codegen/interop/ExternalMethodGen.java

@@ -72,7 +72,7 @@ public static void genJMethodForBExternalFunc(BIRFunction birFunc, ClassWriter c
                     jvmCastGen, jvmConstantsGen, lambdaGenMetadata, types);
         } else {
             methodGen.genJMethodForBFunc(birFunc, cw, birModule, jvmTypeGen, jvmCastGen, jvmConstantsGen,
-                    moduleClassName, attachedType, lambdaGenMetadata);
+                    moduleClassName, attachedType, lambdaGenMetadata, false);
         }
     }