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Java example source code file (MethodEmitter.java)
The MethodEmitter.java Java example source code/* * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package jdk.nashorn.internal.codegen; import static jdk.internal.org.objectweb.asm.Opcodes.ATHROW; import static jdk.internal.org.objectweb.asm.Opcodes.CHECKCAST; import static jdk.internal.org.objectweb.asm.Opcodes.DUP2; import static jdk.internal.org.objectweb.asm.Opcodes.GETFIELD; import static jdk.internal.org.objectweb.asm.Opcodes.GETSTATIC; import static jdk.internal.org.objectweb.asm.Opcodes.GOTO; import static jdk.internal.org.objectweb.asm.Opcodes.H_INVOKESTATIC; import static jdk.internal.org.objectweb.asm.Opcodes.IFEQ; import static jdk.internal.org.objectweb.asm.Opcodes.IFGE; import static jdk.internal.org.objectweb.asm.Opcodes.IFGT; import static jdk.internal.org.objectweb.asm.Opcodes.IFLE; import static jdk.internal.org.objectweb.asm.Opcodes.IFLT; import static jdk.internal.org.objectweb.asm.Opcodes.IFNE; import static jdk.internal.org.objectweb.asm.Opcodes.IFNONNULL; import static jdk.internal.org.objectweb.asm.Opcodes.IFNULL; import static jdk.internal.org.objectweb.asm.Opcodes.IF_ACMPEQ; import static jdk.internal.org.objectweb.asm.Opcodes.IF_ACMPNE; import static jdk.internal.org.objectweb.asm.Opcodes.IF_ICMPEQ; import static jdk.internal.org.objectweb.asm.Opcodes.IF_ICMPNE; import static jdk.internal.org.objectweb.asm.Opcodes.INSTANCEOF; import static jdk.internal.org.objectweb.asm.Opcodes.INVOKEINTERFACE; import static jdk.internal.org.objectweb.asm.Opcodes.INVOKESPECIAL; import static jdk.internal.org.objectweb.asm.Opcodes.INVOKESTATIC; import static jdk.internal.org.objectweb.asm.Opcodes.INVOKEVIRTUAL; import static jdk.internal.org.objectweb.asm.Opcodes.NEW; import static jdk.internal.org.objectweb.asm.Opcodes.PUTFIELD; import static jdk.internal.org.objectweb.asm.Opcodes.PUTSTATIC; import static jdk.internal.org.objectweb.asm.Opcodes.RETURN; import static jdk.nashorn.internal.codegen.CompilerConstants.ARGUMENTS; import static jdk.nashorn.internal.codegen.CompilerConstants.CONSTANTS; import static jdk.nashorn.internal.codegen.CompilerConstants.SCOPE; import static jdk.nashorn.internal.codegen.CompilerConstants.THIS; import static jdk.nashorn.internal.codegen.CompilerConstants.THIS_DEBUGGER; import static jdk.nashorn.internal.codegen.CompilerConstants.VARARGS; import static jdk.nashorn.internal.codegen.CompilerConstants.className; import static jdk.nashorn.internal.codegen.CompilerConstants.constructorNoLookup; import static jdk.nashorn.internal.codegen.CompilerConstants.methodDescriptor; import static jdk.nashorn.internal.codegen.CompilerConstants.staticField; import static jdk.nashorn.internal.codegen.CompilerConstants.virtualCallNoLookup; import java.io.PrintStream; import java.lang.reflect.Array; import java.util.EnumSet; import java.util.List; import jdk.internal.dynalink.support.NameCodec; import jdk.internal.org.objectweb.asm.Handle; import jdk.internal.org.objectweb.asm.MethodVisitor; import jdk.nashorn.internal.codegen.ClassEmitter.Flag; import jdk.nashorn.internal.codegen.CompilerConstants.Call; import jdk.nashorn.internal.codegen.CompilerConstants.FieldAccess; import jdk.nashorn.internal.codegen.types.ArrayType; import jdk.nashorn.internal.codegen.types.BitwiseType; import jdk.nashorn.internal.codegen.types.NumericType; import jdk.nashorn.internal.codegen.types.Type; import jdk.nashorn.internal.ir.FunctionNode; import jdk.nashorn.internal.ir.IdentNode; import jdk.nashorn.internal.ir.LexicalContext; import jdk.nashorn.internal.ir.LiteralNode; import jdk.nashorn.internal.ir.RuntimeNode; import jdk.nashorn.internal.ir.Symbol; import jdk.nashorn.internal.runtime.ArgumentSetter; import jdk.nashorn.internal.runtime.Debug; import jdk.nashorn.internal.runtime.DebugLogger; import jdk.nashorn.internal.runtime.JSType; import jdk.nashorn.internal.runtime.ScriptEnvironment; import jdk.nashorn.internal.runtime.ScriptObject; import jdk.nashorn.internal.runtime.linker.Bootstrap; import jdk.nashorn.internal.runtime.options.Options; /** * This is the main function responsible for emitting method code * in a class. It maintains a type stack and keeps track of control * flow to make sure that the registered instructions don't violate * byte code verification. * * Running Nashorn with -ea will assert as soon as a type stack * becomes corrupt, for easier debugging * * Running Nashorn with -Dnashorn.codegen.debug=true will print * all generated bytecode and labels to stderr, for easier debugging, * including bytecode stack contents */ public class MethodEmitter implements Emitter { /** The ASM MethodVisitor we are plugged into */ private final MethodVisitor method; /** Current type stack for current evaluation */ private Label.Stack stack; /** Parent classEmitter representing the class of this method */ private final ClassEmitter classEmitter; /** FunctionNode representing this method, or null if none exists */ protected FunctionNode functionNode; /** Check whether this emitter ever has a function return point */ private boolean hasReturn; /** The script environment */ private final ScriptEnvironment env; /** Threshold in chars for when string constants should be split */ static final int LARGE_STRING_THRESHOLD = 32 * 1024; /** Debug flag, should we dump all generated bytecode along with stacks? */ private static final DebugLogger LOG = new DebugLogger("codegen", "nashorn.codegen.debug"); private static final boolean DEBUG = LOG.isEnabled(); /** dump stack on a particular line, or -1 if disabled */ private static final int DEBUG_TRACE_LINE; static { final String tl = Options.getStringProperty("nashorn.codegen.debug.trace", "-1"); int line = -1; try { line = Integer.parseInt(tl); } catch (final NumberFormatException e) { //fallthru } DEBUG_TRACE_LINE = line; } /** Bootstrap for normal indy:s */ private static final Handle LINKERBOOTSTRAP = new Handle(H_INVOKESTATIC, Bootstrap.BOOTSTRAP.className(), Bootstrap.BOOTSTRAP.name(), Bootstrap.BOOTSTRAP.descriptor()); /** Bootstrap for runtime node indy:s */ private static final Handle RUNTIMEBOOTSTRAP = new Handle(H_INVOKESTATIC, RuntimeCallSite.BOOTSTRAP.className(), RuntimeCallSite.BOOTSTRAP.name(), RuntimeCallSite.BOOTSTRAP.descriptor()); /** * Constructor - internal use from ClassEmitter only * @see ClassEmitter#method * * @param classEmitter the class emitter weaving the class this method is in * @param method a method visitor */ MethodEmitter(final ClassEmitter classEmitter, final MethodVisitor method) { this(classEmitter, method, null); } /** * Constructor - internal use from ClassEmitter only * @see ClassEmitter#method * * @param classEmitter the class emitter weaving the class this method is in * @param method a method visitor * @param functionNode a function node representing this method */ MethodEmitter(final ClassEmitter classEmitter, final MethodVisitor method, final FunctionNode functionNode) { this.env = classEmitter.getEnv(); this.classEmitter = classEmitter; this.method = method; this.functionNode = functionNode; this.stack = null; } /** * Begin a method * @see Emitter */ @Override public void begin() { classEmitter.beginMethod(this); newStack(); method.visitCode(); } /** * End a method * @see Emitter */ @Override public void end() { method.visitMaxs(0, 0); method.visitEnd(); classEmitter.endMethod(this); } private void newStack() { stack = new Label.Stack(); } @Override public String toString() { return "methodEmitter: " + (functionNode == null ? method : functionNode.getName()).toString() + ' ' + Debug.id(this); } /** * Push a type to the existing stack * @param type the type */ private void pushType(final Type type) { if (type != null) { stack.push(type); } } /** * Pop a type from the existing stack * * @param expected expected type - will assert if wrong * * @return the type that was retrieved */ private Type popType(final Type expected) { final Type type = stack.pop(); assert type.isObject() && expected.isObject() || type.isEquivalentTo(expected) : type + " is not compatible with " + expected; return type; } /** * Pop a type from the existing stack, no matter what it is. * * @return the type */ private Type popType() { return stack.pop(); } /** * Pop a type from the existing stack, ensuring that it is numeric, * assert if not * * @return the type */ private NumericType popNumeric() { final Type type = stack.pop(); assert type.isNumeric() : type + " is not numeric"; return (NumericType)type; } /** * Pop a type from the existing stack, ensuring that it is an integer type * (integer or long), assert if not * * @return the type */ private BitwiseType popInteger() { final Type type = stack.pop(); assert type.isInteger() || type.isLong() : type + " is not an integer or long"; return (BitwiseType)type; } /** * Pop a type from the existing stack, ensuring that it is an array type, * assert if not * * @return the type */ private ArrayType popArray() { final Type type = stack.pop(); assert type.isArray() : type; return (ArrayType)type; } /** * Peek a given number of slots from the top of the stack and return the * type in that slot * * @param pos the number of positions from the top, 0 is the top element * * @return the type at position "pos" on the stack */ final Type peekType(final int pos) { return stack.peek(pos); } /** * Peek at the type at the top of the stack * * @return the type at the top of the stack */ final Type peekType() { return stack.peek(); } /** * Generate code a for instantiating a new object and push the * object type on the stack * * @param classDescriptor class descriptor for the object type * * @return the method emitter */ MethodEmitter _new(final String classDescriptor) { debug("new", classDescriptor); method.visitTypeInsn(NEW, classDescriptor); pushType(Type.OBJECT); return this; } /** * Generate code a for instantiating a new object and push the * object type on the stack * * @param clazz class type to instatiate * * @return the method emitter */ MethodEmitter _new(final Class<?> clazz) { return _new(className(clazz)); } /** * Generate code to call the empty constructor for a class * * @param clazz class type to instatiate * * @return the method emitter */ MethodEmitter newInstance(final Class<?> clazz) { return invoke(constructorNoLookup(clazz)); } /** * Perform a dup, that is, duplicate the top element and * push the duplicate down a given number of positions * on the stack. This is totally type agnostic. * * @param depth the depth on which to put the copy * * @return the method emitter, or null if depth is illegal and * has no instruction equivalent. */ MethodEmitter dup(final int depth) { if (peekType().dup(method, depth) == null) { return null; } debug("dup", depth); switch (depth) { case 0: pushType(peekType()); break; case 1: { final Type p0 = popType(); final Type p1 = popType(); pushType(p0); pushType(p1); pushType(p0); break; } case 2: { final Type p0 = popType(); final Type p1 = popType(); final Type p2 = popType(); pushType(p0); pushType(p2); pushType(p1); pushType(p0); break; } default: assert false : "illegal dup depth = " + depth; return null; } return this; } /** * Perform a dup2, that is, duplicate the top element if it * is a category 2 type, or two top elements if they are category * 1 types, and push them on top of the stack * * @return the method emitter */ MethodEmitter dup2() { debug("dup2"); if (peekType().isCategory2()) { pushType(peekType()); } else { final Type type = get2(); pushType(type); pushType(type); pushType(type); pushType(type); } method.visitInsn(DUP2); return this; } /** * Duplicate the top element on the stack and push it * * @return the method emitter */ MethodEmitter dup() { return dup(0); } /** * Pop the top element of the stack and throw it away * * @return the method emitter */ MethodEmitter pop() { debug("pop", peekType()); popType().pop(method); return this; } /** * Pop the top element of the stack if category 2 type, or the two * top elements of the stack if category 1 types * * @return the method emitter */ MethodEmitter pop2() { if (peekType().isCategory2()) { popType(); } else { get2n(); } return this; } /** * Swap the top two elements of the stack. This is totally * type agnostic and works for all types * * @return the method emitter */ MethodEmitter swap() { debug("swap"); final Type p0 = popType(); final Type p1 = popType(); p0.swap(method, p1); pushType(p0); pushType(p1); debug("after ", p0, p1); return this; } /** * Add a local variable. This is a nop if the symbol has no slot * * @param symbol symbol for the local variable * @param start start of scope * @param end end of scope */ void localVariable(final Symbol symbol, final Label start, final Label end) { if (!symbol.hasSlot()) { return; } String name = symbol.getName(); if (name.equals(THIS.symbolName())) { name = THIS_DEBUGGER.symbolName(); } method.visitLocalVariable(name, symbol.getSymbolType().getDescriptor(), null, start.getLabel(), end.getLabel(), symbol.getSlot()); } /** * Create a new string builder, call the constructor and push the instance to the stack. * * @return the method emitter */ MethodEmitter newStringBuilder() { return invoke(constructorNoLookup(StringBuilder.class)).dup(); } /** * Pop a string and a StringBuilder from the top of the stack and call the append * function of the StringBuilder, appending the string. Pushes the StringBuilder to * the stack when finished. * * @return the method emitter */ MethodEmitter stringBuilderAppend() { convert(Type.STRING); return invoke(virtualCallNoLookup(StringBuilder.class, "append", StringBuilder.class, String.class)); } /** * Pops two integer types from the stack, performs a bitwise and and pushes * the result * * @return the method emitter */ MethodEmitter and() { debug("and"); pushType(get2i().and(method)); return this; } /** * Pops two integer types from the stack, performs a bitwise or and pushes * the result * * @return the method emitter */ MethodEmitter or() { debug("or"); pushType(get2i().or(method)); return this; } /** * Pops two integer types from the stack, performs a bitwise xor and pushes * the result * * @return the method emitter */ MethodEmitter xor() { debug("xor"); pushType(get2i().xor(method)); return this; } /** * Pops two integer types from the stack, performs a bitwise logic shift right and pushes * the result. The shift count, the first element, must be INT. * * @return the method emitter */ MethodEmitter shr() { debug("shr"); popType(Type.INT); pushType(popInteger().shr(method)); return this; } /** * Pops two integer types from the stack, performs a bitwise shift left and and pushes * the result. The shift count, the first element, must be INT. * * @return the method emitter */ MethodEmitter shl() { debug("shl"); popType(Type.INT); pushType(popInteger().shl(method)); return this; } /** * Pops two integer types from the stack, performs a bitwise arithetic shift right and pushes * the result. The shift count, the first element, must be INT. * * @return the method emitter */ MethodEmitter sar() { debug("sar"); popType(Type.INT); pushType(popInteger().sar(method)); return this; } /** * Pops a numeric type from the stack, negates it and pushes the result * * @return the method emitter */ MethodEmitter neg() { debug("neg"); pushType(popNumeric().neg(method)); return this; } /** * Add label for the start of a catch block and push the exception to the * stack * * @param recovery label pointing to start of catch block */ void _catch(final Label recovery) { stack.clear(); stack.push(Type.OBJECT); label(recovery); } /** * Start a try/catch block. * * @param entry start label for try * @param exit end label for try * @param recovery start label for catch * @param typeDescriptor type descriptor for exception */ void _try(final Label entry, final Label exit, final Label recovery, final String typeDescriptor) { method.visitTryCatchBlock(entry.getLabel(), exit.getLabel(), recovery.getLabel(), typeDescriptor); } /** * Start a try/catch block. * * @param entry start label for try * @param exit end label for try * @param recovery start label for catch * @param clazz exception class */ void _try(final Label entry, final Label exit, final Label recovery, final Class<?> clazz) { method.visitTryCatchBlock(entry.getLabel(), exit.getLabel(), recovery.getLabel(), CompilerConstants.className(clazz)); } /** * Start a try/catch block. The catch is "Throwable" - i.e. catch-all * * @param entry start label for try * @param exit end label for try * @param recovery start label for catch */ void _try(final Label entry, final Label exit, final Label recovery) { _try(entry, exit, recovery, (String)null); } /** * Load the constants array * @return this method emitter */ MethodEmitter loadConstants() { getStatic(classEmitter.getUnitClassName(), CONSTANTS.symbolName(), CONSTANTS.descriptor()); assert peekType().isArray() : peekType(); return this; } /** * Push the undefined value for the given type, i.e. * UNDEFINED or UNDEFINEDNUMBER. Currently we have no way of * representing UNDEFINED for INTs and LONGs, so they are not * allowed to be local variables (yet) * * @param type the type for which to push UNDEFINED * @return the method emitter */ MethodEmitter loadUndefined(final Type type) { debug("load undefined ", type); pushType(type.loadUndefined(method)); return this; } /** * Push the empty value for the given type, i.e. EMPTY. * * @param type the type * @return the method emitter */ MethodEmitter loadEmpty(final Type type) { debug("load empty ", type); pushType(type.loadEmpty(method)); return this; } /** * Push null to stack * * @return the method emitter */ MethodEmitter loadNull() { debug("aconst_null"); pushType(Type.OBJECT.ldc(method, null)); return this; } /** * Push a handle representing this class top stack * * @param className name of the class * * @return the method emitter */ MethodEmitter loadType(final String className) { debug("load type", className); method.visitLdcInsn(jdk.internal.org.objectweb.asm.Type.getObjectType(className)); pushType(Type.OBJECT); return this; } /** * Push a boolean constant to the stack. * * @param b value of boolean * * @return the method emitter */ MethodEmitter load(final boolean b) { debug("load boolean", b); pushType(Type.BOOLEAN.ldc(method, b)); return this; } /** * Push an int constant to the stack * * @param i value of the int * * @return the method emitter */ MethodEmitter load(final int i) { debug("load int", i); pushType(Type.INT.ldc(method, i)); return this; } /** * Push a double constant to the stack * * @param d value of the double * * @return the method emitter */ MethodEmitter load(final double d) { debug("load double", d); pushType(Type.NUMBER.ldc(method, d)); return this; } /** * Push an long constant to the stack * * @param l value of the long * * @return the method emitter */ MethodEmitter load(final long l) { debug("load long", l); pushType(Type.LONG.ldc(method, l)); return this; } /** * Fetch the length of an array. * @return Array length. */ MethodEmitter arraylength() { debug("arraylength"); popType(Type.OBJECT); pushType(Type.OBJECT_ARRAY.arraylength(method)); return this; } /** * Push a String constant to the stack * * @param s value of the String * * @return the method emitter */ MethodEmitter load(final String s) { debug("load string", s); if (s == null) { loadNull(); return this; } //NASHORN-142 - split too large string final int length = s.length(); if (length > LARGE_STRING_THRESHOLD) { _new(StringBuilder.class); dup(); load(length); invoke(constructorNoLookup(StringBuilder.class, int.class)); for (int n = 0; n < length; n += LARGE_STRING_THRESHOLD) { final String part = s.substring(n, Math.min(n + LARGE_STRING_THRESHOLD, length)); load(part); stringBuilderAppend(); } invoke(virtualCallNoLookup(StringBuilder.class, "toString", String.class)); return this; } pushType(Type.OBJECT.ldc(method, s)); return this; } /** * Push a local variable to the stack. If the symbol representing * the local variable doesn't have a slot, this is a NOP * * @param symbol the symbol representing the local variable. * * @return the method emitter */ MethodEmitter load(final Symbol symbol) { assert symbol != null; if (symbol.hasSlot()) { final int slot = symbol.getSlot(); debug("load symbol", symbol.getName(), " slot=", slot); final Type type = symbol.getSymbolType().load(method, slot); pushType(type == Type.OBJECT && symbol.isThis() ? Type.THIS : type); } else if (symbol.isParam()) { assert !symbol.isScope(); assert functionNode.isVarArg() : "Non-vararg functions have slotted parameters"; final int index = symbol.getFieldIndex(); if (functionNode.needsArguments()) { // ScriptObject.getArgument(int) on arguments debug("load symbol", symbol.getName(), " arguments index=", index); loadCompilerConstant(ARGUMENTS); load(index); ScriptObject.GET_ARGUMENT.invoke(this); } else { // array load from __varargs__ debug("load symbol", symbol.getName(), " array index=", index); loadCompilerConstant(VARARGS); load(symbol.getFieldIndex()); arrayload(); } } return this; } /** * Push a local variable to the stack, given an explicit bytecode slot * This is used e.g. for stub generation where we know where items like * "this" and "scope" reside. * * @param type the type of the variable * @param slot the slot the variable is in * * @return the method emitter */ MethodEmitter load(final Type type, final int slot) { debug("explicit load", type, slot); final Type loadType = type.load(method, slot); pushType(loadType == Type.OBJECT && isThisSlot(slot) ? Type.THIS : loadType); return this; } private boolean isThisSlot(final int slot) { if (functionNode == null) { return slot == CompilerConstants.JAVA_THIS.slot(); } final int thisSlot = compilerConstant(THIS).getSlot(); assert !functionNode.needsCallee() || thisSlot == 1; // needsCallee -> thisSlot == 1 assert functionNode.needsCallee() || thisSlot == 0; // !needsCallee -> thisSlot == 0 return slot == thisSlot; } /** * Push a method handle to the stack * * @param className class name * @param methodName method name * @param descName descriptor * @param flags flags that describe this handle, e.g. invokespecial new, or invoke virtual * * @return the method emitter */ MethodEmitter loadHandle(final String className, final String methodName, final String descName, final EnumSet<Flag> flags) { debug("load handle "); pushType(Type.OBJECT.ldc(method, new Handle(Flag.getValue(flags), className, methodName, descName))); return this; } private Symbol compilerConstant(final CompilerConstants cc) { return functionNode.getBody().getExistingSymbol(cc.symbolName()); } /** * True if this method has a slot allocated for the scope variable (meaning, something in the method actually needs * the scope). * @return if this method has a slot allocated for the scope variable. */ boolean hasScope() { return compilerConstant(SCOPE).hasSlot(); } MethodEmitter loadCompilerConstant(final CompilerConstants cc) { final Symbol symbol = compilerConstant(cc); if (cc == SCOPE && peekType() == Type.SCOPE) { dup(); return this; } return load(symbol); } void storeCompilerConstant(final CompilerConstants cc) { final Symbol symbol = compilerConstant(cc); debug("store compiler constant ", symbol); store(symbol); } /** * Load an element from an array, determining type automatically * @return the method emitter */ MethodEmitter arrayload() { debug("Xaload"); popType(Type.INT); pushType(popArray().aload(method)); return this; } /** * Pop a value, an index and an array from the stack and store * the value at the given index in the array. */ void arraystore() { debug("Xastore"); final Type value = popType(); final Type index = popType(Type.INT); assert index.isInteger() : "array index is not integer, but " + index; final ArrayType array = popArray(); assert value.isEquivalentTo(array.getElementType()) : "Storing "+value+" into "+array; assert array.isObject(); array.astore(method); } /** * Pop a value from the stack and store it in a local variable represented * by the given symbol. If the symbol has no slot, this is a NOP * * @param symbol symbol to store stack to */ void store(final Symbol symbol) { assert symbol != null : "No symbol to store"; if (symbol.hasSlot()) { final int slot = symbol.getSlot(); debug("store symbol", symbol.getName(), " slot=", slot); popType(symbol.getSymbolType()).store(method, slot); } else if (symbol.isParam()) { assert !symbol.isScope(); assert functionNode.isVarArg() : "Non-vararg functions have slotted parameters"; final int index = symbol.getFieldIndex(); if (functionNode.needsArguments()) { debug("store symbol", symbol.getName(), " arguments index=", index); loadCompilerConstant(ARGUMENTS); load(index); ArgumentSetter.SET_ARGUMENT.invoke(this); } else { // varargs without arguments object - just do array store to __varargs__ debug("store symbol", symbol.getName(), " array index=", index); loadCompilerConstant(VARARGS); load(index); ArgumentSetter.SET_ARRAY_ELEMENT.invoke(this); } } } /** * Pop a value from the stack and store it in a given local variable * slot. * * @param type the type to pop * @param slot the slot */ void store(final Type type, final int slot) { popType(type); type.store(method, slot); } /** * Increment/Decrement a local integer by the given value. * * @param slot the int slot * @param increment the amount to increment */ void iinc(final int slot, final int increment) { debug("iinc"); method.visitIincInsn(slot, increment); } /** * Pop an exception object from the stack and generate code * for throwing it */ public void athrow() { debug("athrow"); final Type receiver = popType(Type.OBJECT); assert receiver.isObject(); method.visitInsn(ATHROW); stack = null; } /** * Pop an object from the stack and perform an instanceof * operation, given a classDescriptor to compare it to. * Push the boolean result 1/0 as an int to the stack * * @param classDescriptor descriptor of the class to type check against * * @return the method emitter */ MethodEmitter _instanceof(final String classDescriptor) { debug("instanceof", classDescriptor); popType(Type.OBJECT); method.visitTypeInsn(INSTANCEOF, classDescriptor); pushType(Type.INT); return this; } /** * Pop an object from the stack and perform an instanceof * operation, given a classDescriptor to compare it to. * Push the boolean result 1/0 as an int to the stack * * @param clazz the type to check instanceof against * * @return the method emitter */ MethodEmitter _instanceof(final Class<?> clazz) { return _instanceof(CompilerConstants.className(clazz)); } /** * Perform a checkcast operation on the object at the top of the * stack. * * @param classDescriptor descriptor of the class to type check against * * @return the method emitter */ MethodEmitter checkcast(final String classDescriptor) { debug("checkcast", classDescriptor); assert peekType().isObject(); method.visitTypeInsn(CHECKCAST, classDescriptor); return this; } /** * Perform a checkcast operation on the object at the top of the * stack. * * @param clazz class to checkcast against * * @return the method emitter */ MethodEmitter checkcast(final Class<?> clazz) { return checkcast(CompilerConstants.className(clazz)); } /** * Instantiate a new array given a length that is popped * from the stack and the array type * * @param arrayType the type of the array * * @return the method emitter */ MethodEmitter newarray(final ArrayType arrayType) { debug("newarray ", "arrayType=", arrayType); popType(Type.INT); //LENGTH pushType(arrayType.newarray(method)); return this; } /** * Instantiate a multidimensional array with a given number of dimensions. * On the stack are dim lengths of the sub arrays. * * @param arrayType type of the array * @param dims number of dimensions * * @return the method emitter */ MethodEmitter multinewarray(final ArrayType arrayType, final int dims) { debug("multianewarray ", arrayType, dims); for (int i = 0; i < dims; i++) { popType(Type.INT); //LENGTH } pushType(arrayType.newarray(method, dims)); return this; } /** * Helper function to pop and type check the appropriate arguments * from the stack given a method signature * * @param signature method signature * * @return return type of method */ private Type fixParamStack(final String signature) { final Type[] params = Type.getMethodArguments(signature); for (int i = params.length - 1; i >= 0; i--) { popType(params[i]); } final Type returnType = Type.getMethodReturnType(signature); return returnType; } /** * Generate an invocation to a Call structure * @see CompilerConstants * * @param call the call object * * @return the method emitter */ MethodEmitter invoke(final Call call) { return call.invoke(this); } private MethodEmitter invoke(final int opcode, final String className, final String methodName, final String methodDescriptor, final boolean hasReceiver) { final Type returnType = fixParamStack(methodDescriptor); if (hasReceiver) { popType(Type.OBJECT); } method.visitMethodInsn(opcode, className, methodName, methodDescriptor); if (returnType != null) { pushType(returnType); } return this; } /** * Pop receiver from stack, perform an invoke special * * @param className class name * @param methodName method name * @param methodDescriptor descriptor * * @return the method emitter */ MethodEmitter invokespecial(final String className, final String methodName, final String methodDescriptor) { debug("invokespecial", className, ".", methodName, methodDescriptor); return invoke(INVOKESPECIAL, className, methodName, methodDescriptor, true); } /** * Pop receiver from stack, perform an invoke virtual, push return value if any * * @param className class name * @param methodName method name * @param methodDescriptor descriptor * * @return the method emitter */ MethodEmitter invokevirtual(final String className, final String methodName, final String methodDescriptor) { debug("invokevirtual", className, ".", methodName, methodDescriptor, " ", stack); return invoke(INVOKEVIRTUAL, className, methodName, methodDescriptor, true); } /** * Perform an invoke static and push the return value if any * * @param className class name * @param methodName method name * @param methodDescriptor descriptor * * @return the method emitter */ MethodEmitter invokestatic(final String className, final String methodName, final String methodDescriptor) { debug("invokestatic", className, ".", methodName, methodDescriptor); invoke(INVOKESTATIC, className, methodName, methodDescriptor, false); return this; } /** * Perform an invoke static and replace the return type if we know better, e.g. Global.allocate * that allocates an array should return an ObjectArray type as a NativeArray counts as that * * @param className class name * @param methodName method name * @param methodDescriptor descriptor * @param returnType return type override * * @return the method emitter */ MethodEmitter invokeStatic(final String className, final String methodName, final String methodDescriptor, final Type returnType) { invokestatic(className, methodName, methodDescriptor); popType(); pushType(returnType); return this; } /** * Pop receiver from stack, perform an invoke interface and push return value if any * * @param className class name * @param methodName method name * @param methodDescriptor descriptor * * @return the method emitter */ MethodEmitter invokeinterface(final String className, final String methodName, final String methodDescriptor) { debug("invokeinterface", className, ".", methodName, methodDescriptor); return invoke(INVOKEINTERFACE, className, methodName, methodDescriptor, true); } static jdk.internal.org.objectweb.asm.Label[] getLabels(final Label... table) { final jdk.internal.org.objectweb.asm.Label[] internalLabels = new jdk.internal.org.objectweb.asm.Label[table.length]; for (int i = 0; i < table.length; i++) { internalLabels[i] = table[i].getLabel(); } return internalLabels; } /** * Generate a lookup switch, popping the switch value from the stack * * @param defaultLabel default label * @param values case values for the table * @param table default label */ void lookupswitch(final Label defaultLabel, final int[] values, final Label... table) {//Collection<Label> table) { debug("lookupswitch", peekType()); popType(Type.INT); method.visitLookupSwitchInsn(defaultLabel.getLabel(), values, getLabels(table)); } /** * Generate a table switch * @param lo low value * @param hi high value * @param defaultLabel default label * @param table label table */ void tableswitch(final int lo, final int hi, final Label defaultLabel, final Label... table) { debug("tableswitch", peekType()); popType(Type.INT); method.visitTableSwitchInsn(lo, hi, defaultLabel.getLabel(), getLabels(table)); } /** * Abstraction for performing a conditional jump of any type * * @see MethodEmitter.Condition * * @param cond the condition to test * @param trueLabel the destination label is condition is true */ void conditionalJump(final Condition cond, final Label trueLabel) { conditionalJump(cond, cond != Condition.GT && cond != Condition.GE, trueLabel); } /** * Abstraction for performing a conditional jump of any type, * including a dcmpg/dcmpl semantic for doubles. * * @param cond the condition to test * @param isCmpG is this a dcmpg for numbers, false if it's a dcmpl * @param trueLabel the destination label if condition is true */ void conditionalJump(final Condition cond, final boolean isCmpG, final Label trueLabel) { if (peekType().isCategory2()) { debug("[ld]cmp isCmpG=", isCmpG); pushType(get2n().cmp(method, isCmpG)); jump(Condition.toUnary(cond), trueLabel, 1); } else { debug("if", cond); jump(Condition.toBinary(cond, peekType().isObject()), trueLabel, 2); } } MethodEmitter registerReturn() { setHasReturn(); return this; } void setHasReturn() { this.hasReturn = true; } /** * Perform a non void return, popping the type from the stack * * @param type the type for the return */ void _return(final Type type) { debug("return", type); assert stack.size() == 1 : "Only return value on stack allowed at return point - depth=" + stack.size() + " stack = " + stack; final Type stackType = peekType(); if (!Type.areEquivalent(type, stackType)) { convert(type); } popType(type)._return(method); stack = null; } /** * Perform a return using the stack top value as the guide for the type */ void _return() { _return(peekType()); } /** * Perform a void return. */ void returnVoid() { debug("return [void]"); assert stack.isEmpty() : stack; method.visitInsn(RETURN); stack = null; } /** * Goto, possibly when splitting is taking place. If * a splitNode exists, we need to handle the case that the * jump target is another method * * @param label destination label */ void splitAwareGoto(final LexicalContext lc, final Label label) { _goto(label); } /** * Perform a comparison of two number types that are popped from the stack * * @param isCmpG is this a dcmpg semantic, false if it's a dcmpl semantic * * @return the method emitter */ MethodEmitter cmp(final boolean isCmpG) { pushType(get2n().cmp(method, isCmpG)); return this; } /** * Helper function for jumps, conditional or not * @param opcode opcode for jump * @param label destination * @param n elements on stack to compare, 0-2 */ private void jump(final int opcode, final Label label, final int n) { for (int i = 0; i < n; i++) { assert peekType().isInteger() || peekType().isBoolean() || peekType().isObject() : "expecting integer type or object for jump, but found " + peekType(); popType(); } mergeStackTo(label); method.visitJumpInsn(opcode, label.getLabel()); } /** * Generate an if_acmpeq * * @param label label to true case */ void if_acmpeq(final Label label) { debug("if_acmpeq", label); jump(IF_ACMPEQ, label, 2); } /** * Generate an if_acmpne * * @param label label to true case */ void if_acmpne(final Label label) { debug("if_acmpne", label); jump(IF_ACMPNE, label, 2); } /** * Generate an ifnull * * @param label label to true case */ void ifnull(final Label label) { debug("ifnull", label); jump(IFNULL, label, 1); } /** * Generate an ifnonnull * * @param label label to true case */ void ifnonnull(final Label label) { debug("ifnonnull", label); jump(IFNONNULL, label, 1); } /** * Generate an ifeq * * @param label label to true case */ void ifeq(final Label label) { debug("ifeq ", label); jump(IFEQ, label, 1); } /** * Generate an if_icmpeq * * @param label label to true case */ void if_icmpeq(final Label label) { debug("if_icmpeq", label); jump(IF_ICMPEQ, label, 2); } /** * Generate an if_ne * * @param label label to true case */ void ifne(final Label label) { debug("ifne", label); jump(IFNE, label, 1); } /** * Generate an if_icmpne * * @param label label to true case */ void if_icmpne(final Label label) { debug("if_icmpne", label); jump(IF_ICMPNE, label, 2); } /** * Generate an iflt * * @param label label to true case */ void iflt(final Label label) { debug("iflt", label); jump(IFLT, label, 1); } /** * Generate an ifle * * @param label label to true case */ void ifle(final Label label) { debug("ifle", label); jump(IFLE, label, 1); } /** * Generate an ifgt * * @param label label to true case */ void ifgt(final Label label) { debug("ifgt", label); jump(IFGT, label, 1); } /** * Generate an ifge * * @param label label to true case */ void ifge(final Label label) { debug("ifge", label); jump(IFGE, label, 1); } /** * Unconditional jump to a label * * @param label destination label */ void _goto(final Label label) { //debug("goto", label); jump(GOTO, label, 0); stack = null; //whoever reaches the point after us provides the stack, because we don't } /** * Examine two stacks and make sure they are of the same size and their * contents are equivalent to each other * @param s0 first stack * @param s1 second stack * * @return true if stacks are equivalent, false otherwise */ /** * A join in control flow - helper function that makes sure all entry stacks * discovered for the join point so far are equivalent * * MergeStack: we are about to enter a label. If its stack, label.getStack() is null * we have never been here before. Then we are expected to carry a stack with us. * * @param label label */ private void mergeStackTo(final Label label) { //sometimes we can do a merge stack without having a stack - i.e. when jumping ahead to dead code //see NASHORN-73. So far we had been saved by the line number nodes. This should have been fixed //by Lower removing everything after an unconditionally executed terminating statement OR a break //or continue in a block. Previously code left over after breaks and continues was still there //and caused bytecode to be generated - which crashed on stack not being there, as the merge //was not in fact preceeded by a visit. Furthermore, this led to ASM putting out its NOP NOP NOP //ATHROW sequences instead of no code being generated at all. This should now be fixed. assert stack != null : label + " entered with no stack. deadcode that remains?"; final Label.Stack labelStack = label.getStack(); if (labelStack == null) { label.setStack(stack.copy()); return; } assert stack.isEquivalentTo(labelStack) : "stacks " + stack + " is not equivalent with " + labelStack + " at join point"; } /** * Register a new label, enter it here. * * @param label the label */ void label(final Label label) { /* * If stack == null, this means that we came here not through a fallthrough. * E.g. a label after an athrow. Then we create a new stack if one doesn't exist * for this location already. */ if (stack == null) { stack = label.getStack(); if (stack == null) { newStack(); } } debug_label(label); mergeStackTo(label); //we have to merge our stack to whatever is in the label method.visitLabel(label.getLabel()); } /** * Pop element from stack, convert to given type * * @param to type to convert to * * @return the method emitter */ MethodEmitter convert(final Type to) { final Type type = peekType().convert(method, to); if (type != null) { if (!peekType().isEquivalentTo(to)) { debug("convert", peekType(), "->", to); } popType(); pushType(type); } return this; } /** * Helper function - expect two types that are equivalent * * @return common type */ private Type get2() { final Type p0 = popType(); final Type p1 = popType(); assert p0.isEquivalentTo(p1) : "expecting equivalent types on stack but got " + p0 + " and " + p1; return p0; } /** * Helper function - expect two types that are integer types and equivalent * * @return common type */ private BitwiseType get2i() { final BitwiseType p0 = popInteger(); final BitwiseType p1 = popInteger(); assert p0.isEquivalentTo(p1) : "expecting equivalent types on stack but got " + p0 + " and " + p1; return p0; } /** * Helper function - expect two types that are numbers and equivalent * * @return common type */ private NumericType get2n() { final NumericType p0 = popNumeric(); final NumericType p1 = popNumeric(); assert p0.isEquivalentTo(p1) : "expecting equivalent types on stack but got " + p0 + " and " + p1; return p0; } /** * Pop two numbers, perform addition and push result * * @return the method emitter */ MethodEmitter add() { debug("add"); pushType(get2().add(method)); return this; } /** * Pop two numbers, perform subtraction and push result * * @return the method emitter */ MethodEmitter sub() { debug("sub"); pushType(get2n().sub(method)); return this; } /** * Pop two numbers, perform multiplication and push result * * @return the method emitter */ MethodEmitter mul() { debug("mul "); pushType(get2n().mul(method)); return this; } /** * Pop two numbers, perform division and push result * * @return the method emitter */ MethodEmitter div() { debug("div"); pushType(get2n().div(method)); return this; } /** * Pop two numbers, calculate remainder and push result * * @return the method emitter */ MethodEmitter rem() { debug("rem"); pushType(get2n().rem(method)); return this; } /** * Retrieve the top <tt>count types on the stack without modifying it. * * @param count number of types to return * @return array of Types */ protected Type[] getTypesFromStack(final int count) { final Type[] types = new Type[count]; int pos = 0; for (int i = count - 1; i >= 0; i--) { types[i] = stack.peek(pos++); } return types; } /** * Helper function to generate a function signature based on stack contents * and argument count and return type * * @param returnType return type * @param argCount argument count * * @return function signature for stack contents */ private String getDynamicSignature(final Type returnType, final int argCount) { final Type[] paramTypes = new Type[argCount]; int pos = 0; for (int i = argCount - 1; i >= 0; i--) { paramTypes[i] = stack.peek(pos++); } final String descriptor = Type.getMethodDescriptor(returnType, paramTypes); for (int i = 0; i < argCount; i++) { popType(paramTypes[argCount - i - 1]); } return descriptor; } /** * Generate a dynamic new * * @param argCount number of arguments * @param flags callsite flags * * @return the method emitter */ MethodEmitter dynamicNew(final int argCount, final int flags) { debug("dynamic_new", "argcount=", argCount); final String signature = getDynamicSignature(Type.OBJECT, argCount); method.visitInvokeDynamicInsn("dyn:new", signature, LINKERBOOTSTRAP, flags); pushType(Type.OBJECT); //TODO fix result type return this; } /** * Generate a dynamic call * * @param returnType return type * @param argCount number of arguments * @param flags callsite flags * * @return the method emitter */ MethodEmitter dynamicCall(final Type returnType, final int argCount, final int flags) { debug("dynamic_call", "args=", argCount, "returnType=", returnType); final String signature = getDynamicSignature(returnType, argCount); // +1 because the function itself is the 1st parameter for dynamic calls (what you call - call target) debug(" signature", signature); method.visitInvokeDynamicInsn("dyn:call", signature, LINKERBOOTSTRAP, flags); pushType(returnType); return this; } /** * Generate a dynamic call for a runtime node * * @param name tag for the invoke dynamic for this runtime node * @param returnType return type * @param request RuntimeNode request * * @return the method emitter */ MethodEmitter dynamicRuntimeCall(final String name, final Type returnType, final RuntimeNode.Request request) { debug("dynamic_runtime_call", name, "args=", request.getArity(), "returnType=", returnType); final String signature = getDynamicSignature(returnType, request.getArity()); debug(" signature", signature); method.visitInvokeDynamicInsn(name, signature, RUNTIMEBOOTSTRAP); pushType(returnType); return this; } /** * Generate dynamic getter. Pop scope from stack. Push result * * @param valueType type of the value to set * @param name name of property * @param flags call site flags * @param isMethod should it prefer retrieving methods * * @return the method emitter */ MethodEmitter dynamicGet(final Type valueType, final String name, final int flags, final boolean isMethod) { debug("dynamic_get", name, valueType); Type type = valueType; if (type.isObject() || type.isBoolean()) { type = Type.OBJECT; //promote e.g strings to object generic setter } popType(Type.SCOPE); method.visitInvokeDynamicInsn((isMethod ? "dyn:getMethod|getProp|getElem:" : "dyn:getProp|getElem|getMethod:") + NameCodec.encode(name), Type.getMethodDescriptor(type, Type.OBJECT), LINKERBOOTSTRAP, flags); pushType(type); convert(valueType); //most probably a nop return this; } /** * Generate dynamic setter. Pop receiver and property from stack. * * @param valueType the type of the value to set * @param name name of property * @param flags call site flags */ void dynamicSet(final String name, final int flags) { debug("dynamic_set", name, peekType()); Type type = peekType(); if (type.isObject() || type.isBoolean()) { //promote strings to objects etc type = Type.OBJECT; convert(Type.OBJECT); //TODO bad- until we specialize boolean setters, } popType(type); popType(Type.SCOPE); method.visitInvokeDynamicInsn("dyn:setProp|setElem:" + NameCodec.encode(name), methodDescriptor(void.class, Object.class, type.getTypeClass()), LINKERBOOTSTRAP, flags); } /** * Dynamic getter for indexed structures. Pop index and receiver from stack, * generate appropriate signatures based on types * * @param result result type for getter * @param flags call site flags for getter * @param isMethod should it prefer retrieving methods * * @return the method emitter */ MethodEmitter dynamicGetIndex(final Type result, final int flags, final boolean isMethod) { debug("dynamic_get_index", peekType(1), "[", peekType(), "]"); Type resultType = result; if (result.isBoolean()) { resultType = Type.OBJECT; // INT->OBJECT to avoid another dimension of cross products in the getters. TODO } Type index = peekType(); if (index.isObject() || index.isBoolean()) { index = Type.OBJECT; //e.g. string->object convert(Type.OBJECT); } popType(); popType(Type.OBJECT); final String signature = Type.getMethodDescriptor(resultType, Type.OBJECT /*e.g STRING->OBJECT*/, index); method.visitInvokeDynamicInsn(isMethod ? "dyn:getMethod|getElem|getProp" : "dyn:getElem|getProp|getMethod", signature, LINKERBOOTSTRAP, flags); pushType(resultType); if (result.isBoolean()) { convert(Type.BOOLEAN); } return this; } /** * Dynamic setter for indexed structures. Pop value, index and receiver from * stack, generate appropriate signature based on types * * @param flags call site flags for setter */ void dynamicSetIndex(final int flags) { debug("dynamic_set_index", peekType(2), "[", peekType(1), "] =", peekType()); Type value = peekType(); if (value.isObject() || value.isBoolean()) { value = Type.OBJECT; //e.g. STRING->OBJECT - one descriptor for all object types convert(Type.OBJECT); } popType(); Type index = peekType(); if (index.isObject() || index.isBoolean()) { index = Type.OBJECT; //e.g. string->object convert(Type.OBJECT); } popType(index); final Type receiver = popType(Type.OBJECT); assert receiver.isObject(); method.visitInvokeDynamicInsn("dyn:setElem|setProp", methodDescriptor(void.class, receiver.getTypeClass(), index.getTypeClass(), value.getTypeClass()), LINKERBOOTSTRAP, flags); } /** * Load a key value in the proper form. * * @param key */ //TODO move this and break it apart MethodEmitter loadKey(final Object key) { if (key instanceof IdentNode) { method.visitLdcInsn(((IdentNode) key).getName()); } else if (key instanceof LiteralNode) { method.visitLdcInsn(((LiteralNode<?>)key).getString()); } else { method.visitLdcInsn(JSType.toString(key)); } pushType(Type.OBJECT); //STRING return this; } @SuppressWarnings("fallthrough") private static Type fieldType(final String desc) { switch (desc) { case "Z": case "B": case "C": case "S": case "I": return Type.INT; case "F": assert false; case "D": return Type.NUMBER; case "J": return Type.LONG; default: assert desc.startsWith("[") || desc.startsWith("L") : desc + " is not an object type"; switch (desc.charAt(0)) { case 'L': return Type.OBJECT; case '[': return Type.typeFor(Array.newInstance(fieldType(desc.substring(1)).getTypeClass(), 0).getClass()); default: assert false; } return Type.OBJECT; } } /** * Generate get for a field access * * @param fa the field access * * @return the method emitter */ MethodEmitter getField(final FieldAccess fa) { return fa.get(this); } /** * Generate set for a field access * * @param fa the field access */ void putField(final FieldAccess fa) { fa.put(this); } /** * Get the value of a non-static field, pop the receiver from the stack, * push value to the stack * * @param className class * @param fieldName field name * @param fieldDescriptor field descriptor * * @return the method emitter */ MethodEmitter getField(final String className, final String fieldName, final String fieldDescriptor) { debug("getfield", "receiver=", peekType(), className, ".", fieldName, fieldDescriptor); final Type receiver = popType(); assert receiver.isObject(); method.visitFieldInsn(GETFIELD, className, fieldName, fieldDescriptor); pushType(fieldType(fieldDescriptor)); return this; } /** * Get the value of a static field, push it to the stack * * @param className class * @param fieldName field name * @param fieldDescriptor field descriptor * * @return the method emitter */ MethodEmitter getStatic(final String className, final String fieldName, final String fieldDescriptor) { debug("getstatic", className, ".", fieldName, ".", fieldDescriptor); method.visitFieldInsn(GETSTATIC, className, fieldName, fieldDescriptor); pushType(fieldType(fieldDescriptor)); return this; } /** * Pop value and field from stack and write to a non-static field * * @param className class * @param fieldName field name * @param fieldDescriptor field descriptor */ void putField(final String className, final String fieldName, final String fieldDescriptor) { debug("putfield", "receiver=", peekType(1), "value=", peekType()); popType(fieldType(fieldDescriptor)); popType(Type.OBJECT); method.visitFieldInsn(PUTFIELD, className, fieldName, fieldDescriptor); } /** * Pop value from stack and write to a static field * * @param className class * @param fieldName field name * @param fieldDescriptor field descriptor */ void putStatic(final String className, final String fieldName, final String fieldDescriptor) { debug("putfield", "value=", peekType()); popType(fieldType(fieldDescriptor)); method.visitFieldInsn(PUTSTATIC, className, fieldName, fieldDescriptor); } /** * Register line number at a label * * @param line line number * @param label label */ void lineNumber(final int line) { if (env._debug_lines) { debug_label("[LINE]", line); final jdk.internal.org.objectweb.asm.Label l = new jdk.internal.org.objectweb.asm.Label(); method.visitLabel(l); method.visitLineNumber(line, l); } } /* * Debugging below */ private final FieldAccess ERR_STREAM = staticField(System.class, "err", PrintStream.class); private final Call PRINT = virtualCallNoLookup(PrintStream.class, "print", void.class, Object.class); private final Call PRINTLN = virtualCallNoLookup(PrintStream.class, "println", void.class, Object.class); private final Call PRINT_STACKTRACE = virtualCallNoLookup(Throwable.class, "printStackTrace", void.class); /** * Emit a System.err.print statement of whatever is on top of the bytecode stack */ void print() { getField(ERR_STREAM); swap(); convert(Type.OBJECT); invoke(PRINT); } /** * Emit a System.err.println statement of whatever is on top of the bytecode stack */ void println() { getField(ERR_STREAM); swap(); convert(Type.OBJECT); invoke(PRINTLN); } /** * Emit a System.err.print statement * @param string string to print */ void print(final String string) { getField(ERR_STREAM); load(string); invoke(PRINT); } /** * Emit a System.err.println statement * @param string string to print */ void println(final String string) { getField(ERR_STREAM); load(string); invoke(PRINTLN); } /** * Print a stacktrace to S */ void stacktrace() { _new(Throwable.class); dup(); invoke(constructorNoLookup(Throwable.class)); invoke(PRINT_STACKTRACE); } private static int linePrefix = 0; /** * Debug function that outputs generated bytecode and stack contents * * @param args debug information to print */ private void debug(final Object... args) { if (DEBUG) { debug(30, args); } } /** * Debug function that outputs generated bytecode and stack contents * for a label - indentation is currently the only thing that differs * * @param args debug information to print */ private void debug_label(final Object... args) { if (DEBUG) { debug(22, args); } } private void debug(final int padConstant, final Object... args) { if (DEBUG) { final StringBuilder sb = new StringBuilder(); int pad; sb.append('#'); sb.append(++linePrefix); pad = 5 - sb.length(); while (pad > 0) { sb.append(' '); pad--; } if (stack != null && !stack.isEmpty()) { sb.append("{"); sb.append(stack.size()); sb.append(":"); for (int pos = 0; pos < stack.size(); pos++) { final Type t = stack.peek(pos); if (t == Type.SCOPE) { sb.append("scope"); } else if (t == Type.THIS) { sb.append("this"); } else if (t.isObject()) { String desc = t.getDescriptor(); int i; for (i = 0; desc.charAt(i) == '[' && i < desc.length(); i++) { sb.append('['); } desc = desc.substring(i); final int slash = desc.lastIndexOf('/'); if (slash != -1) { desc = desc.substring(slash + 1, desc.length() - 1); } if ("Object".equals(desc)) { sb.append('O'); } else { sb.append(desc); } } else { sb.append(t.getDescriptor()); } if (pos + 1 < stack.size()) { sb.append(' '); } } sb.append('}'); sb.append(' '); } pad = padConstant - sb.length(); while (pad > 0) { sb.append(' '); pad--; } for (final Object arg : args) { sb.append(arg); sb.append(' '); } if (env != null) { //early bootstrap code doesn't have inited context yet LOG.info(sb); if (DEBUG_TRACE_LINE == linePrefix) { new Throwable().printStackTrace(LOG.getOutputStream()); } } } } /** * Set the current function node being emitted * @param functionNode the function node */ void setFunctionNode(final FunctionNode functionNode) { this.functionNode = functionNode; } boolean hasReturn() { return hasReturn; } List<Label> getExternalTargets() { return null; } } Other Java examples (source code examples)Here is a short list of links related to this Java MethodEmitter.java source code file: |
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