http://git-wip-us.apache.org/repos/asf/tajo/blob/7603a3d4/tajo-thirdparty/asm/src/main/java/org/apache/tajo/org/objectweb/asm/MethodWriter.java ---------------------------------------------------------------------- diff --git a/tajo-thirdparty/asm/src/main/java/org/apache/tajo/org/objectweb/asm/MethodWriter.java b/tajo-thirdparty/asm/src/main/java/org/apache/tajo/org/objectweb/asm/MethodWriter.java new file mode 100644 index 0000000..290cf97 --- /dev/null +++ b/tajo-thirdparty/asm/src/main/java/org/apache/tajo/org/objectweb/asm/MethodWriter.java @@ -0,0 +1,2685 @@ +/*** + * ASM: a very small and fast Java bytecode manipulation framework + * Copyright (c) 2000-2011 INRIA, France Telecom + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF + * THE POSSIBILITY OF SUCH DAMAGE. + */ +package org.apache.tajo.org.objectweb.asm; + +/** + * A {@link MethodVisitor} that generates methods in bytecode form. Each visit + * method of this class appends the bytecode corresponding to the visited + * instruction to a byte vector, in the order these methods are called. + * + * @author Eric Bruneton + * @author Eugene Kuleshov + */ +class MethodWriter extends MethodVisitor { + + /** + * Pseudo access flag used to denote constructors. + */ + static final int ACC_CONSTRUCTOR = 0x80000; + + /** + * Frame has exactly the same locals as the previous stack map frame and + * number of stack items is zero. + */ + static final int SAME_FRAME = 0; // to 63 (0-3f) + + /** + * Frame has exactly the same locals as the previous stack map frame and + * number of stack items is 1 + */ + static final int SAME_LOCALS_1_STACK_ITEM_FRAME = 64; // to 127 (40-7f) + + /** + * Reserved for future use + */ + static final int RESERVED = 128; + + /** + * Frame has exactly the same locals as the previous stack map frame and + * number of stack items is 1. Offset is bigger then 63; + */ + static final int SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED = 247; // f7 + + /** + * Frame where current locals are the same as the locals in the previous + * frame, except that the k last locals are absent. The value of k is given + * by the formula 251-frame_type. + */ + static final int CHOP_FRAME = 248; // to 250 (f8-fA) + + /** + * Frame has exactly the same locals as the previous stack map frame and + * number of stack items is zero. Offset is bigger then 63; + */ + static final int SAME_FRAME_EXTENDED = 251; // fb + + /** + * Frame where current locals are the same as the locals in the previous + * frame, except that k additional locals are defined. The value of k is + * given by the formula frame_type-251. + */ + static final int APPEND_FRAME = 252; // to 254 // fc-fe + + /** + * Full frame + */ + static final int FULL_FRAME = 255; // ff + + /** + * Indicates that the stack map frames must be recomputed from scratch. In + * this case the maximum stack size and number of local variables is also + * recomputed from scratch. + * + * @see #compute + */ + private static final int FRAMES = 0; + + /** + * Indicates that the maximum stack size and number of local variables must + * be automatically computed. + * + * @see #compute + */ + private static final int MAXS = 1; + + /** + * Indicates that nothing must be automatically computed. + * + * @see #compute + */ + private static final int NOTHING = 2; + + /** + * The class writer to which this method must be added. + */ + final ClassWriter cw; + + /** + * Access flags of this method. + */ + private int access; + + /** + * The index of the constant pool item that contains the name of this + * method. + */ + private final int name; + + /** + * The index of the constant pool item that contains the descriptor of this + * method. + */ + private final int desc; + + /** + * The descriptor of this method. + */ + private final String descriptor; + + /** + * The signature of this method. + */ + String signature; + + /** + * If not zero, indicates that the code of this method must be copied from + * the ClassReader associated to this writer in <code>cw.cr</code>. More + * precisely, this field gives the index of the first byte to copied from + * <code>cw.cr.b</code>. + */ + int classReaderOffset; + + /** + * If not zero, indicates that the code of this method must be copied from + * the ClassReader associated to this writer in <code>cw.cr</code>. More + * precisely, this field gives the number of bytes to copied from + * <code>cw.cr.b</code>. + */ + int classReaderLength; + + /** + * Number of exceptions that can be thrown by this method. + */ + int exceptionCount; + + /** + * The exceptions that can be thrown by this method. More precisely, this + * array contains the indexes of the constant pool items that contain the + * internal names of these exception classes. + */ + int[] exceptions; + + /** + * The annotation default attribute of this method. May be <tt>null</tt>. + */ + private ByteVector annd; + + /** + * The runtime visible annotations of this method. May be <tt>null</tt>. + */ + private AnnotationWriter anns; + + /** + * The runtime invisible annotations of this method. May be <tt>null</tt>. + */ + private AnnotationWriter ianns; + + /** + * The runtime visible parameter annotations of this method. May be + * <tt>null</tt>. + */ + private AnnotationWriter[] panns; + + /** + * The runtime invisible parameter annotations of this method. May be + * <tt>null</tt>. + */ + private AnnotationWriter[] ipanns; + + /** + * The number of synthetic parameters of this method. + */ + private int synthetics; + + /** + * The non standard attributes of the method. + */ + private Attribute attrs; + + /** + * The bytecode of this method. + */ + private ByteVector code = new ByteVector(); + + /** + * Maximum stack size of this method. + */ + private int maxStack; + + /** + * Maximum number of local variables for this method. + */ + private int maxLocals; + + /** + * Number of local variables in the current stack map frame. + */ + private int currentLocals; + + /** + * Number of stack map frames in the StackMapTable attribute. + */ + private int frameCount; + + /** + * The StackMapTable attribute. + */ + private ByteVector stackMap; + + /** + * The offset of the last frame that was written in the StackMapTable + * attribute. + */ + private int previousFrameOffset; + + /** + * The last frame that was written in the StackMapTable attribute. + * + * @see #frame + */ + private int[] previousFrame; + + /** + * The current stack map frame. The first element contains the offset of the + * instruction to which the frame corresponds, the second element is the + * number of locals and the third one is the number of stack elements. The + * local variables start at index 3 and are followed by the operand stack + * values. In summary frame[0] = offset, frame[1] = nLocal, frame[2] = + * nStack, frame[3] = nLocal. All types are encoded as integers, with the + * same format as the one used in {@link Label}, but limited to BASE types. + */ + private int[] frame; + + /** + * Number of elements in the exception handler list. + */ + private int handlerCount; + + /** + * The first element in the exception handler list. + */ + private Handler firstHandler; + + /** + * The last element in the exception handler list. + */ + private Handler lastHandler; + + /** + * Number of entries in the LocalVariableTable attribute. + */ + private int localVarCount; + + /** + * The LocalVariableTable attribute. + */ + private ByteVector localVar; + + /** + * Number of entries in the LocalVariableTypeTable attribute. + */ + private int localVarTypeCount; + + /** + * The LocalVariableTypeTable attribute. + */ + private ByteVector localVarType; + + /** + * Number of entries in the LineNumberTable attribute. + */ + private int lineNumberCount; + + /** + * The LineNumberTable attribute. + */ + private ByteVector lineNumber; + + /** + * The non standard attributes of the method's code. + */ + private Attribute cattrs; + + /** + * Indicates if some jump instructions are too small and need to be resized. + */ + private boolean resize; + + /** + * The number of subroutines in this method. + */ + private int subroutines; + + // ------------------------------------------------------------------------ + + /* + * Fields for the control flow graph analysis algorithm (used to compute the + * maximum stack size). A control flow graph contains one node per "basic + * block", and one edge per "jump" from one basic block to another. Each + * node (i.e., each basic block) is represented by the Label object that + * corresponds to the first instruction of this basic block. Each node also + * stores the list of its successors in the graph, as a linked list of Edge + * objects. + */ + + /** + * Indicates what must be automatically computed. + * + * @see #FRAMES + * @see #MAXS + * @see #NOTHING + */ + private final int compute; + + /** + * A list of labels. This list is the list of basic blocks in the method, + * i.e. a list of Label objects linked to each other by their + * {@link Label#successor} field, in the order they are visited by + * {@link MethodVisitor#visitLabel}, and starting with the first basic + * block. + */ + private Label labels; + + /** + * The previous basic block. + */ + private Label previousBlock; + + /** + * The current basic block. + */ + private Label currentBlock; + + /** + * The (relative) stack size after the last visited instruction. This size + * is relative to the beginning of the current basic block, i.e., the true + * stack size after the last visited instruction is equal to the + * {@link Label#inputStackTop beginStackSize} of the current basic block + * plus <tt>stackSize</tt>. + */ + private int stackSize; + + /** + * The (relative) maximum stack size after the last visited instruction. + * This size is relative to the beginning of the current basic block, i.e., + * the true maximum stack size after the last visited instruction is equal + * to the {@link Label#inputStackTop beginStackSize} of the current basic + * block plus <tt>stackSize</tt>. + */ + private int maxStackSize; + + // ------------------------------------------------------------------------ + // Constructor + // ------------------------------------------------------------------------ + + /** + * Constructs a new {@link MethodWriter}. + * + * @param cw + * the class writer in which the method must be added. + * @param access + * the method's access flags (see {@link Opcodes}). + * @param name + * the method's name. + * @param desc + * the method's descriptor (see {@link Type}). + * @param signature + * the method's signature. May be <tt>null</tt>. + * @param exceptions + * the internal names of the method's exceptions. May be + * <tt>null</tt>. + * @param computeMaxs + * <tt>true</tt> if the maximum stack size and number of local + * variables must be automatically computed. + * @param computeFrames + * <tt>true</tt> if the stack map tables must be recomputed from + * scratch. + */ + MethodWriter(final ClassWriter cw, final int access, final String name, + final String desc, final String signature, + final String[] exceptions, final boolean computeMaxs, + final boolean computeFrames) { + super(Opcodes.ASM4); + if (cw.firstMethod == null) { + cw.firstMethod = this; + } else { + cw.lastMethod.mv = this; + } + cw.lastMethod = this; + this.cw = cw; + this.access = access; + if ("<init>".equals(name)) { + this.access |= ACC_CONSTRUCTOR; + } + this.name = cw.newUTF8(name); + this.desc = cw.newUTF8(desc); + this.descriptor = desc; + if (ClassReader.SIGNATURES) { + this.signature = signature; + } + if (exceptions != null && exceptions.length > 0) { + exceptionCount = exceptions.length; + this.exceptions = new int[exceptionCount]; + for (int i = 0; i < exceptionCount; ++i) { + this.exceptions[i] = cw.newClass(exceptions[i]); + } + } + this.compute = computeFrames ? FRAMES : (computeMaxs ? MAXS : NOTHING); + if (computeMaxs || computeFrames) { + // updates maxLocals + int size = Type.getArgumentsAndReturnSizes(descriptor) >> 2; + if ((access & Opcodes.ACC_STATIC) != 0) { + --size; + } + maxLocals = size; + currentLocals = size; + // creates and visits the label for the first basic block + labels = new Label(); + labels.status |= Label.PUSHED; + visitLabel(labels); + } + } + + // ------------------------------------------------------------------------ + // Implementation of the MethodVisitor abstract class + // ------------------------------------------------------------------------ + + @Override + public AnnotationVisitor visitAnnotationDefault() { + if (!ClassReader.ANNOTATIONS) { + return null; + } + annd = new ByteVector(); + return new AnnotationWriter(cw, false, annd, null, 0); + } + + @Override + public AnnotationVisitor visitAnnotation(final String desc, + final boolean visible) { + if (!ClassReader.ANNOTATIONS) { + return null; + } + ByteVector bv = new ByteVector(); + // write type, and reserve space for values count + bv.putShort(cw.newUTF8(desc)).putShort(0); + AnnotationWriter aw = new AnnotationWriter(cw, true, bv, bv, 2); + if (visible) { + aw.next = anns; + anns = aw; + } else { + aw.next = ianns; + ianns = aw; + } + return aw; + } + + @Override + public AnnotationVisitor visitParameterAnnotation(final int parameter, + final String desc, final boolean visible) { + if (!ClassReader.ANNOTATIONS) { + return null; + } + ByteVector bv = new ByteVector(); + if ("Ljava/lang/Synthetic;".equals(desc)) { + // workaround for a bug in javac with synthetic parameters + // see ClassReader.readParameterAnnotations + synthetics = Math.max(synthetics, parameter + 1); + return new AnnotationWriter(cw, false, bv, null, 0); + } + // write type, and reserve space for values count + bv.putShort(cw.newUTF8(desc)).putShort(0); + AnnotationWriter aw = new AnnotationWriter(cw, true, bv, bv, 2); + if (visible) { + if (panns == null) { + panns = new AnnotationWriter[Type.getArgumentTypes(descriptor).length]; + } + aw.next = panns[parameter]; + panns[parameter] = aw; + } else { + if (ipanns == null) { + ipanns = new AnnotationWriter[Type.getArgumentTypes(descriptor).length]; + } + aw.next = ipanns[parameter]; + ipanns[parameter] = aw; + } + return aw; + } + + @Override + public void visitAttribute(final Attribute attr) { + if (attr.isCodeAttribute()) { + attr.next = cattrs; + cattrs = attr; + } else { + attr.next = attrs; + attrs = attr; + } + } + + @Override + public void visitCode() { + } + + @Override + public void visitFrame(final int type, final int nLocal, + final Object[] local, final int nStack, final Object[] stack) { + if (!ClassReader.FRAMES || compute == FRAMES) { + return; + } + + if (type == Opcodes.F_NEW) { + if (previousFrame == null) { + visitImplicitFirstFrame(); + } + currentLocals = nLocal; + int frameIndex = startFrame(code.length, nLocal, nStack); + for (int i = 0; i < nLocal; ++i) { + if (local[i] instanceof String) { + frame[frameIndex++] = Frame.OBJECT + | cw.addType((String) local[i]); + } else if (local[i] instanceof Integer) { + frame[frameIndex++] = ((Integer) local[i]).intValue(); + } else { + frame[frameIndex++] = Frame.UNINITIALIZED + | cw.addUninitializedType("", + ((Label) local[i]).position); + } + } + for (int i = 0; i < nStack; ++i) { + if (stack[i] instanceof String) { + frame[frameIndex++] = Frame.OBJECT + | cw.addType((String) stack[i]); + } else if (stack[i] instanceof Integer) { + frame[frameIndex++] = ((Integer) stack[i]).intValue(); + } else { + frame[frameIndex++] = Frame.UNINITIALIZED + | cw.addUninitializedType("", + ((Label) stack[i]).position); + } + } + endFrame(); + } else { + int delta; + if (stackMap == null) { + stackMap = new ByteVector(); + delta = code.length; + } else { + delta = code.length - previousFrameOffset - 1; + if (delta < 0) { + if (type == Opcodes.F_SAME) { + return; + } else { + throw new IllegalStateException(); + } + } + } + + switch (type) { + case Opcodes.F_FULL: + currentLocals = nLocal; + stackMap.putByte(FULL_FRAME).putShort(delta).putShort(nLocal); + for (int i = 0; i < nLocal; ++i) { + writeFrameType(local[i]); + } + stackMap.putShort(nStack); + for (int i = 0; i < nStack; ++i) { + writeFrameType(stack[i]); + } + break; + case Opcodes.F_APPEND: + currentLocals += nLocal; + stackMap.putByte(SAME_FRAME_EXTENDED + nLocal).putShort(delta); + for (int i = 0; i < nLocal; ++i) { + writeFrameType(local[i]); + } + break; + case Opcodes.F_CHOP: + currentLocals -= nLocal; + stackMap.putByte(SAME_FRAME_EXTENDED - nLocal).putShort(delta); + break; + case Opcodes.F_SAME: + if (delta < 64) { + stackMap.putByte(delta); + } else { + stackMap.putByte(SAME_FRAME_EXTENDED).putShort(delta); + } + break; + case Opcodes.F_SAME1: + if (delta < 64) { + stackMap.putByte(SAME_LOCALS_1_STACK_ITEM_FRAME + delta); + } else { + stackMap.putByte(SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED) + .putShort(delta); + } + writeFrameType(stack[0]); + break; + } + + previousFrameOffset = code.length; + ++frameCount; + } + + maxStack = Math.max(maxStack, nStack); + maxLocals = Math.max(maxLocals, currentLocals); + } + + @Override + public void visitInsn(final int opcode) { + // adds the instruction to the bytecode of the method + code.putByte(opcode); + // update currentBlock + // Label currentBlock = this.currentBlock; + if (currentBlock != null) { + if (compute == FRAMES) { + currentBlock.frame.execute(opcode, 0, null, null); + } else { + // updates current and max stack sizes + int size = stackSize + Frame.SIZE[opcode]; + if (size > maxStackSize) { + maxStackSize = size; + } + stackSize = size; + } + // if opcode == ATHROW or xRETURN, ends current block (no successor) + if ((opcode >= Opcodes.IRETURN && opcode <= Opcodes.RETURN) + || opcode == Opcodes.ATHROW) { + noSuccessor(); + } + } + } + + @Override + public void visitIntInsn(final int opcode, final int operand) { + // Label currentBlock = this.currentBlock; + if (currentBlock != null) { + if (compute == FRAMES) { + currentBlock.frame.execute(opcode, operand, null, null); + } else if (opcode != Opcodes.NEWARRAY) { + // updates current and max stack sizes only for NEWARRAY + // (stack size variation = 0 for BIPUSH or SIPUSH) + int size = stackSize + 1; + if (size > maxStackSize) { + maxStackSize = size; + } + stackSize = size; + } + } + // adds the instruction to the bytecode of the method + if (opcode == Opcodes.SIPUSH) { + code.put12(opcode, operand); + } else { // BIPUSH or NEWARRAY + code.put11(opcode, operand); + } + } + + @Override + public void visitVarInsn(final int opcode, final int var) { + // Label currentBlock = this.currentBlock; + if (currentBlock != null) { + if (compute == FRAMES) { + currentBlock.frame.execute(opcode, var, null, null); + } else { + // updates current and max stack sizes + if (opcode == Opcodes.RET) { + // no stack change, but end of current block (no successor) + currentBlock.status |= Label.RET; + // save 'stackSize' here for future use + // (see {@link #findSubroutineSuccessors}) + currentBlock.inputStackTop = stackSize; + noSuccessor(); + } else { // xLOAD or xSTORE + int size = stackSize + Frame.SIZE[opcode]; + if (size > maxStackSize) { + maxStackSize = size; + } + stackSize = size; + } + } + } + if (compute != NOTHING) { + // updates max locals + int n; + if (opcode == Opcodes.LLOAD || opcode == Opcodes.DLOAD + || opcode == Opcodes.LSTORE || opcode == Opcodes.DSTORE) { + n = var + 2; + } else { + n = var + 1; + } + if (n > maxLocals) { + maxLocals = n; + } + } + // adds the instruction to the bytecode of the method + if (var < 4 && opcode != Opcodes.RET) { + int opt; + if (opcode < Opcodes.ISTORE) { + /* ILOAD_0 */ + opt = 26 + ((opcode - Opcodes.ILOAD) << 2) + var; + } else { + /* ISTORE_0 */ + opt = 59 + ((opcode - Opcodes.ISTORE) << 2) + var; + } + code.putByte(opt); + } else if (var >= 256) { + code.putByte(196 /* WIDE */).put12(opcode, var); + } else { + code.put11(opcode, var); + } + if (opcode >= Opcodes.ISTORE && compute == FRAMES && handlerCount > 0) { + visitLabel(new Label()); + } + } + + @Override + public void visitTypeInsn(final int opcode, final String type) { + Item i = cw.newClassItem(type); + // Label currentBlock = this.currentBlock; + if (currentBlock != null) { + if (compute == FRAMES) { + currentBlock.frame.execute(opcode, code.length, cw, i); + } else if (opcode == Opcodes.NEW) { + // updates current and max stack sizes only if opcode == NEW + // (no stack change for ANEWARRAY, CHECKCAST, INSTANCEOF) + int size = stackSize + 1; + if (size > maxStackSize) { + maxStackSize = size; + } + stackSize = size; + } + } + // adds the instruction to the bytecode of the method + code.put12(opcode, i.index); + } + + @Override + public void visitFieldInsn(final int opcode, final String owner, + final String name, final String desc) { + Item i = cw.newFieldItem(owner, name, desc); + // Label currentBlock = this.currentBlock; + if (currentBlock != null) { + if (compute == FRAMES) { + currentBlock.frame.execute(opcode, 0, cw, i); + } else { + int size; + // computes the stack size variation + char c = desc.charAt(0); + switch (opcode) { + case Opcodes.GETSTATIC: + size = stackSize + (c == 'D' || c == 'J' ? 2 : 1); + break; + case Opcodes.PUTSTATIC: + size = stackSize + (c == 'D' || c == 'J' ? -2 : -1); + break; + case Opcodes.GETFIELD: + size = stackSize + (c == 'D' || c == 'J' ? 1 : 0); + break; + // case Constants.PUTFIELD: + default: + size = stackSize + (c == 'D' || c == 'J' ? -3 : -2); + break; + } + // updates current and max stack sizes + if (size > maxStackSize) { + maxStackSize = size; + } + stackSize = size; + } + } + // adds the instruction to the bytecode of the method + code.put12(opcode, i.index); + } + + @Override + public void visitMethodInsn(final int opcode, final String owner, + final String name, final String desc) { + boolean itf = opcode == Opcodes.INVOKEINTERFACE; + Item i = cw.newMethodItem(owner, name, desc, itf); + int argSize = i.intVal; + // Label currentBlock = this.currentBlock; + if (currentBlock != null) { + if (compute == FRAMES) { + currentBlock.frame.execute(opcode, 0, cw, i); + } else { + /* + * computes the stack size variation. In order not to recompute + * several times this variation for the same Item, we use the + * intVal field of this item to store this variation, once it + * has been computed. More precisely this intVal field stores + * the sizes of the arguments and of the return value + * corresponding to desc. + */ + if (argSize == 0) { + // the above sizes have not been computed yet, + // so we compute them... + argSize = Type.getArgumentsAndReturnSizes(desc); + // ... and we save them in order + // not to recompute them in the future + i.intVal = argSize; + } + int size; + if (opcode == Opcodes.INVOKESTATIC) { + size = stackSize - (argSize >> 2) + (argSize & 0x03) + 1; + } else { + size = stackSize - (argSize >> 2) + (argSize & 0x03); + } + // updates current and max stack sizes + if (size > maxStackSize) { + maxStackSize = size; + } + stackSize = size; + } + } + // adds the instruction to the bytecode of the method + if (itf) { + if (argSize == 0) { + argSize = Type.getArgumentsAndReturnSizes(desc); + i.intVal = argSize; + } + code.put12(Opcodes.INVOKEINTERFACE, i.index).put11(argSize >> 2, 0); + } else { + code.put12(opcode, i.index); + } + } + + @Override + public void visitInvokeDynamicInsn(final String name, final String desc, + final Handle bsm, final Object... bsmArgs) { + Item i = cw.newInvokeDynamicItem(name, desc, bsm, bsmArgs); + int argSize = i.intVal; + // Label currentBlock = this.currentBlock; + if (currentBlock != null) { + if (compute == FRAMES) { + currentBlock.frame.execute(Opcodes.INVOKEDYNAMIC, 0, cw, i); + } else { + /* + * computes the stack size variation. In order not to recompute + * several times this variation for the same Item, we use the + * intVal field of this item to store this variation, once it + * has been computed. More precisely this intVal field stores + * the sizes of the arguments and of the return value + * corresponding to desc. + */ + if (argSize == 0) { + // the above sizes have not been computed yet, + // so we compute them... + argSize = Type.getArgumentsAndReturnSizes(desc); + // ... and we save them in order + // not to recompute them in the future + i.intVal = argSize; + } + int size = stackSize - (argSize >> 2) + (argSize & 0x03) + 1; + + // updates current and max stack sizes + if (size > maxStackSize) { + maxStackSize = size; + } + stackSize = size; + } + } + // adds the instruction to the bytecode of the method + code.put12(Opcodes.INVOKEDYNAMIC, i.index); + code.putShort(0); + } + + @Override + public void visitJumpInsn(final int opcode, final Label label) { + Label nextInsn = null; + // Label currentBlock = this.currentBlock; + if (currentBlock != null) { + if (compute == FRAMES) { + currentBlock.frame.execute(opcode, 0, null, null); + // 'label' is the target of a jump instruction + label.getFirst().status |= Label.TARGET; + // adds 'label' as a successor of this basic block + addSuccessor(Edge.NORMAL, label); + if (opcode != Opcodes.GOTO) { + // creates a Label for the next basic block + nextInsn = new Label(); + } + } else { + if (opcode == Opcodes.JSR) { + if ((label.status & Label.SUBROUTINE) == 0) { + label.status |= Label.SUBROUTINE; + ++subroutines; + } + currentBlock.status |= Label.JSR; + addSuccessor(stackSize + 1, label); + // creates a Label for the next basic block + nextInsn = new Label(); + /* + * note that, by construction in this method, a JSR block + * has at least two successors in the control flow graph: + * the first one leads the next instruction after the JSR, + * while the second one leads to the JSR target. + */ + } else { + // updates current stack size (max stack size unchanged + // because stack size variation always negative in this + // case) + stackSize += Frame.SIZE[opcode]; + addSuccessor(stackSize, label); + } + } + } + // adds the instruction to the bytecode of the method + if ((label.status & Label.RESOLVED) != 0 + && label.position - code.length < Short.MIN_VALUE) { + /* + * case of a backward jump with an offset < -32768. In this case we + * automatically replace GOTO with GOTO_W, JSR with JSR_W and IFxxx + * <l> with IFNOTxxx <l'> GOTO_W <l>, where IFNOTxxx is the + * "opposite" opcode of IFxxx (i.e., IFNE for IFEQ) and where <l'> + * designates the instruction just after the GOTO_W. + */ + if (opcode == Opcodes.GOTO) { + code.putByte(200); // GOTO_W + } else if (opcode == Opcodes.JSR) { + code.putByte(201); // JSR_W + } else { + // if the IF instruction is transformed into IFNOT GOTO_W the + // next instruction becomes the target of the IFNOT instruction + if (nextInsn != null) { + nextInsn.status |= Label.TARGET; + } + code.putByte(opcode <= 166 ? ((opcode + 1) ^ 1) - 1 + : opcode ^ 1); + code.putShort(8); // jump offset + code.putByte(200); // GOTO_W + } + label.put(this, code, code.length - 1, true); + } else { + /* + * case of a backward jump with an offset >= -32768, or of a forward + * jump with, of course, an unknown offset. In these cases we store + * the offset in 2 bytes (which will be increased in + * resizeInstructions, if needed). + */ + code.putByte(opcode); + label.put(this, code, code.length - 1, false); + } + if (currentBlock != null) { + if (nextInsn != null) { + // if the jump instruction is not a GOTO, the next instruction + // is also a successor of this instruction. Calling visitLabel + // adds the label of this next instruction as a successor of the + // current block, and starts a new basic block + visitLabel(nextInsn); + } + if (opcode == Opcodes.GOTO) { + noSuccessor(); + } + } + } + + @Override + public void visitLabel(final Label label) { + // resolves previous forward references to label, if any + resize |= label.resolve(this, code.length, code.data); + // updates currentBlock + if ((label.status & Label.DEBUG) != 0) { + return; + } + if (compute == FRAMES) { + if (currentBlock != null) { + if (label.position == currentBlock.position) { + // successive labels, do not start a new basic block + currentBlock.status |= (label.status & Label.TARGET); + label.frame = currentBlock.frame; + return; + } + // ends current block (with one new successor) + addSuccessor(Edge.NORMAL, label); + } + // begins a new current block + currentBlock = label; + if (label.frame == null) { + label.frame = new Frame(); + label.frame.owner = label; + } + // updates the basic block list + if (previousBlock != null) { + if (label.position == previousBlock.position) { + previousBlock.status |= (label.status & Label.TARGET); + label.frame = previousBlock.frame; + currentBlock = previousBlock; + return; + } + previousBlock.successor = label; + } + previousBlock = label; + } else if (compute == MAXS) { + if (currentBlock != null) { + // ends current block (with one new successor) + currentBlock.outputStackMax = maxStackSize; + addSuccessor(stackSize, label); + } + // begins a new current block + currentBlock = label; + // resets the relative current and max stack sizes + stackSize = 0; + maxStackSize = 0; + // updates the basic block list + if (previousBlock != null) { + previousBlock.successor = label; + } + previousBlock = label; + } + } + + @Override + public void visitLdcInsn(final Object cst) { + Item i = cw.newConstItem(cst); + // Label currentBlock = this.currentBlock; + if (currentBlock != null) { + if (compute == FRAMES) { + currentBlock.frame.execute(Opcodes.LDC, 0, cw, i); + } else { + int size; + // computes the stack size variation + if (i.type == ClassWriter.LONG || i.type == ClassWriter.DOUBLE) { + size = stackSize + 2; + } else { + size = stackSize + 1; + } + // updates current and max stack sizes + if (size > maxStackSize) { + maxStackSize = size; + } + stackSize = size; + } + } + // adds the instruction to the bytecode of the method + int index = i.index; + if (i.type == ClassWriter.LONG || i.type == ClassWriter.DOUBLE) { + code.put12(20 /* LDC2_W */, index); + } else if (index >= 256) { + code.put12(19 /* LDC_W */, index); + } else { + code.put11(Opcodes.LDC, index); + } + } + + @Override + public void visitIincInsn(final int var, final int increment) { + if (currentBlock != null) { + if (compute == FRAMES) { + currentBlock.frame.execute(Opcodes.IINC, var, null, null); + } + } + if (compute != NOTHING) { + // updates max locals + int n = var + 1; + if (n > maxLocals) { + maxLocals = n; + } + } + // adds the instruction to the bytecode of the method + if ((var > 255) || (increment > 127) || (increment < -128)) { + code.putByte(196 /* WIDE */).put12(Opcodes.IINC, var) + .putShort(increment); + } else { + code.putByte(Opcodes.IINC).put11(var, increment); + } + } + + @Override + public void visitTableSwitchInsn(final int min, final int max, + final Label dflt, final Label... labels) { + // adds the instruction to the bytecode of the method + int source = code.length; + code.putByte(Opcodes.TABLESWITCH); + code.putByteArray(null, 0, (4 - code.length % 4) % 4); + dflt.put(this, code, source, true); + code.putInt(min).putInt(max); + for (int i = 0; i < labels.length; ++i) { + labels[i].put(this, code, source, true); + } + // updates currentBlock + visitSwitchInsn(dflt, labels); + } + + @Override + public void visitLookupSwitchInsn(final Label dflt, final int[] keys, + final Label[] labels) { + // adds the instruction to the bytecode of the method + int source = code.length; + code.putByte(Opcodes.LOOKUPSWITCH); + code.putByteArray(null, 0, (4 - code.length % 4) % 4); + dflt.put(this, code, source, true); + code.putInt(labels.length); + for (int i = 0; i < labels.length; ++i) { + code.putInt(keys[i]); + labels[i].put(this, code, source, true); + } + // updates currentBlock + visitSwitchInsn(dflt, labels); + } + + private void visitSwitchInsn(final Label dflt, final Label[] labels) { + // Label currentBlock = this.currentBlock; + if (currentBlock != null) { + if (compute == FRAMES) { + currentBlock.frame.execute(Opcodes.LOOKUPSWITCH, 0, null, null); + // adds current block successors + addSuccessor(Edge.NORMAL, dflt); + dflt.getFirst().status |= Label.TARGET; + for (int i = 0; i < labels.length; ++i) { + addSuccessor(Edge.NORMAL, labels[i]); + labels[i].getFirst().status |= Label.TARGET; + } + } else { + // updates current stack size (max stack size unchanged) + --stackSize; + // adds current block successors + addSuccessor(stackSize, dflt); + for (int i = 0; i < labels.length; ++i) { + addSuccessor(stackSize, labels[i]); + } + } + // ends current block + noSuccessor(); + } + } + + @Override + public void visitMultiANewArrayInsn(final String desc, final int dims) { + Item i = cw.newClassItem(desc); + // Label currentBlock = this.currentBlock; + if (currentBlock != null) { + if (compute == FRAMES) { + currentBlock.frame.execute(Opcodes.MULTIANEWARRAY, dims, cw, i); + } else { + // updates current stack size (max stack size unchanged because + // stack size variation always negative or null) + stackSize += 1 - dims; + } + } + // adds the instruction to the bytecode of the method + code.put12(Opcodes.MULTIANEWARRAY, i.index).putByte(dims); + } + + @Override + public void visitTryCatchBlock(final Label start, final Label end, + final Label handler, final String type) { + ++handlerCount; + Handler h = new Handler(); + h.start = start; + h.end = end; + h.handler = handler; + h.desc = type; + h.type = type != null ? cw.newClass(type) : 0; + if (lastHandler == null) { + firstHandler = h; + } else { + lastHandler.next = h; + } + lastHandler = h; + } + + @Override + public void visitLocalVariable(final String name, final String desc, + final String signature, final Label start, final Label end, + final int index) { + if (signature != null) { + if (localVarType == null) { + localVarType = new ByteVector(); + } + ++localVarTypeCount; + localVarType.putShort(start.position) + .putShort(end.position - start.position) + .putShort(cw.newUTF8(name)).putShort(cw.newUTF8(signature)) + .putShort(index); + } + if (localVar == null) { + localVar = new ByteVector(); + } + ++localVarCount; + localVar.putShort(start.position) + .putShort(end.position - start.position) + .putShort(cw.newUTF8(name)).putShort(cw.newUTF8(desc)) + .putShort(index); + if (compute != NOTHING) { + // updates max locals + char c = desc.charAt(0); + int n = index + (c == 'J' || c == 'D' ? 2 : 1); + if (n > maxLocals) { + maxLocals = n; + } + } + } + + @Override + public void visitLineNumber(final int line, final Label start) { + if (lineNumber == null) { + lineNumber = new ByteVector(); + } + ++lineNumberCount; + lineNumber.putShort(start.position); + lineNumber.putShort(line); + } + + @Override + public void visitMaxs(final int maxStack, final int maxLocals) { + if (ClassReader.FRAMES && compute == FRAMES) { + // completes the control flow graph with exception handler blocks + Handler handler = firstHandler; + while (handler != null) { + Label l = handler.start.getFirst(); + Label h = handler.handler.getFirst(); + Label e = handler.end.getFirst(); + // computes the kind of the edges to 'h' + String t = handler.desc == null ? "java/lang/Throwable" + : handler.desc; + int kind = Frame.OBJECT | cw.addType(t); + // h is an exception handler + h.status |= Label.TARGET; + // adds 'h' as a successor of labels between 'start' and 'end' + while (l != e) { + // creates an edge to 'h' + Edge b = new Edge(); + b.info = kind; + b.successor = h; + // adds it to the successors of 'l' + b.next = l.successors; + l.successors = b; + // goes to the next label + l = l.successor; + } + handler = handler.next; + } + + // creates and visits the first (implicit) frame + Frame f = labels.frame; + Type[] args = Type.getArgumentTypes(descriptor); + f.initInputFrame(cw, access, args, this.maxLocals); + visitFrame(f); + + /* + * fix point algorithm: mark the first basic block as 'changed' + * (i.e. put it in the 'changed' list) and, while there are changed + * basic blocks, choose one, mark it as unchanged, and update its + * successors (which can be changed in the process). + */ + int max = 0; + Label changed = labels; + while (changed != null) { + // removes a basic block from the list of changed basic blocks + Label l = changed; + changed = changed.next; + l.next = null; + f = l.frame; + // a reachable jump target must be stored in the stack map + if ((l.status & Label.TARGET) != 0) { + l.status |= Label.STORE; + } + // all visited labels are reachable, by definition + l.status |= Label.REACHABLE; + // updates the (absolute) maximum stack size + int blockMax = f.inputStack.length + l.outputStackMax; + if (blockMax > max) { + max = blockMax; + } + // updates the successors of the current basic block + Edge e = l.successors; + while (e != null) { + Label n = e.successor.getFirst(); + boolean change = f.merge(cw, n.frame, e.info); + if (change && n.next == null) { + // if n has changed and is not already in the 'changed' + // list, adds it to this list + n.next = changed; + changed = n; + } + e = e.next; + } + } + + // visits all the frames that must be stored in the stack map + Label l = labels; + while (l != null) { + f = l.frame; + if ((l.status & Label.STORE) != 0) { + visitFrame(f); + } + if ((l.status & Label.REACHABLE) == 0) { + // finds start and end of dead basic block + Label k = l.successor; + int start = l.position; + int end = (k == null ? code.length : k.position) - 1; + // if non empty basic block + if (end >= start) { + max = Math.max(max, 1); + // replaces instructions with NOP ... NOP ATHROW + for (int i = start; i < end; ++i) { + code.data[i] = Opcodes.NOP; + } + code.data[end] = (byte) Opcodes.ATHROW; + // emits a frame for this unreachable block + int frameIndex = startFrame(start, 0, 1); + frame[frameIndex] = Frame.OBJECT + | cw.addType("java/lang/Throwable"); + endFrame(); + // removes the start-end range from the exception + // handlers + firstHandler = Handler.remove(firstHandler, l, k); + } + } + l = l.successor; + } + + handler = firstHandler; + handlerCount = 0; + while (handler != null) { + handlerCount += 1; + handler = handler.next; + } + + this.maxStack = max; + } else if (compute == MAXS) { + // completes the control flow graph with exception handler blocks + Handler handler = firstHandler; + while (handler != null) { + Label l = handler.start; + Label h = handler.handler; + Label e = handler.end; + // adds 'h' as a successor of labels between 'start' and 'end' + while (l != e) { + // creates an edge to 'h' + Edge b = new Edge(); + b.info = Edge.EXCEPTION; + b.successor = h; + // adds it to the successors of 'l' + if ((l.status & Label.JSR) == 0) { + b.next = l.successors; + l.successors = b; + } else { + // if l is a JSR block, adds b after the first two edges + // to preserve the hypothesis about JSR block successors + // order (see {@link #visitJumpInsn}) + b.next = l.successors.next.next; + l.successors.next.next = b; + } + // goes to the next label + l = l.successor; + } + handler = handler.next; + } + + if (subroutines > 0) { + // completes the control flow graph with the RET successors + /* + * first step: finds the subroutines. This step determines, for + * each basic block, to which subroutine(s) it belongs. + */ + // finds the basic blocks that belong to the "main" subroutine + int id = 0; + labels.visitSubroutine(null, 1, subroutines); + // finds the basic blocks that belong to the real subroutines + Label l = labels; + while (l != null) { + if ((l.status & Label.JSR) != 0) { + // the subroutine is defined by l's TARGET, not by l + Label subroutine = l.successors.next.successor; + // if this subroutine has not been visited yet... + if ((subroutine.status & Label.VISITED) == 0) { + // ...assigns it a new id and finds its basic blocks + id += 1; + subroutine.visitSubroutine(null, (id / 32L) << 32 + | (1L << (id % 32)), subroutines); + } + } + l = l.successor; + } + // second step: finds the successors of RET blocks + l = labels; + while (l != null) { + if ((l.status & Label.JSR) != 0) { + Label L = labels; + while (L != null) { + L.status &= ~Label.VISITED2; + L = L.successor; + } + // the subroutine is defined by l's TARGET, not by l + Label subroutine = l.successors.next.successor; + subroutine.visitSubroutine(l, 0, subroutines); + } + l = l.successor; + } + } + + /* + * control flow analysis algorithm: while the block stack is not + * empty, pop a block from this stack, update the max stack size, + * compute the true (non relative) begin stack size of the + * successors of this block, and push these successors onto the + * stack (unless they have already been pushed onto the stack). + * Note: by hypothesis, the {@link Label#inputStackTop} of the + * blocks in the block stack are the true (non relative) beginning + * stack sizes of these blocks. + */ + int max = 0; + Label stack = labels; + while (stack != null) { + // pops a block from the stack + Label l = stack; + stack = stack.next; + // computes the true (non relative) max stack size of this block + int start = l.inputStackTop; + int blockMax = start + l.outputStackMax; + // updates the global max stack size + if (blockMax > max) { + max = blockMax; + } + // analyzes the successors of the block + Edge b = l.successors; + if ((l.status & Label.JSR) != 0) { + // ignores the first edge of JSR blocks (virtual successor) + b = b.next; + } + while (b != null) { + l = b.successor; + // if this successor has not already been pushed... + if ((l.status & Label.PUSHED) == 0) { + // computes its true beginning stack size... + l.inputStackTop = b.info == Edge.EXCEPTION ? 1 : start + + b.info; + // ...and pushes it onto the stack + l.status |= Label.PUSHED; + l.next = stack; + stack = l; + } + b = b.next; + } + } + this.maxStack = Math.max(maxStack, max); + } else { + this.maxStack = maxStack; + this.maxLocals = maxLocals; + } + } + + @Override + public void visitEnd() { + } + + // ------------------------------------------------------------------------ + // Utility methods: control flow analysis algorithm + // ------------------------------------------------------------------------ + + /** + * Adds a successor to the {@link #currentBlock currentBlock} block. + * + * @param info + * information about the control flow edge to be added. + * @param successor + * the successor block to be added to the current block. + */ + private void addSuccessor(final int info, final Label successor) { + // creates and initializes an Edge object... + Edge b = new Edge(); + b.info = info; + b.successor = successor; + // ...and adds it to the successor list of the currentBlock block + b.next = currentBlock.successors; + currentBlock.successors = b; + } + + /** + * Ends the current basic block. This method must be used in the case where + * the current basic block does not have any successor. + */ + private void noSuccessor() { + if (compute == FRAMES) { + Label l = new Label(); + l.frame = new Frame(); + l.frame.owner = l; + l.resolve(this, code.length, code.data); + previousBlock.successor = l; + previousBlock = l; + } else { + currentBlock.outputStackMax = maxStackSize; + } + currentBlock = null; + } + + // ------------------------------------------------------------------------ + // Utility methods: stack map frames + // ------------------------------------------------------------------------ + + /** + * Visits a frame that has been computed from scratch. + * + * @param f + * the frame that must be visited. + */ + private void visitFrame(final Frame f) { + int i, t; + int nTop = 0; + int nLocal = 0; + int nStack = 0; + int[] locals = f.inputLocals; + int[] stacks = f.inputStack; + // computes the number of locals (ignores TOP types that are just after + // a LONG or a DOUBLE, and all trailing TOP types) + for (i = 0; i < locals.length; ++i) { + t = locals[i]; + if (t == Frame.TOP) { + ++nTop; + } else { + nLocal += nTop + 1; + nTop = 0; + } + if (t == Frame.LONG || t == Frame.DOUBLE) { + ++i; + } + } + // computes the stack size (ignores TOP types that are just after + // a LONG or a DOUBLE) + for (i = 0; i < stacks.length; ++i) { + t = stacks[i]; + ++nStack; + if (t == Frame.LONG || t == Frame.DOUBLE) { + ++i; + } + } + // visits the frame and its content + int frameIndex = startFrame(f.owner.position, nLocal, nStack); + for (i = 0; nLocal > 0; ++i, --nLocal) { + t = locals[i]; + frame[frameIndex++] = t; + if (t == Frame.LONG || t == Frame.DOUBLE) { + ++i; + } + } + for (i = 0; i < stacks.length; ++i) { + t = stacks[i]; + frame[frameIndex++] = t; + if (t == Frame.LONG || t == Frame.DOUBLE) { + ++i; + } + } + endFrame(); + } + + /** + * Visit the implicit first frame of this method. + */ + private void visitImplicitFirstFrame() { + // There can be at most descriptor.length() + 1 locals + int frameIndex = startFrame(0, descriptor.length() + 1, 0); + if ((access & Opcodes.ACC_STATIC) == 0) { + if ((access & ACC_CONSTRUCTOR) == 0) { + frame[frameIndex++] = Frame.OBJECT | cw.addType(cw.thisName); + } else { + frame[frameIndex++] = 6; // Opcodes.UNINITIALIZED_THIS; + } + } + int i = 1; + loop: while (true) { + int j = i; + switch (descriptor.charAt(i++)) { + case 'Z': + case 'C': + case 'B': + case 'S': + case 'I': + frame[frameIndex++] = 1; // Opcodes.INTEGER; + break; + case 'F': + frame[frameIndex++] = 2; // Opcodes.FLOAT; + break; + case 'J': + frame[frameIndex++] = 4; // Opcodes.LONG; + break; + case 'D': + frame[frameIndex++] = 3; // Opcodes.DOUBLE; + break; + case '[': + while (descriptor.charAt(i) == '[') { + ++i; + } + if (descriptor.charAt(i) == 'L') { + ++i; + while (descriptor.charAt(i) != ';') { + ++i; + } + } + frame[frameIndex++] = Frame.OBJECT + | cw.addType(descriptor.substring(j, ++i)); + break; + case 'L': + while (descriptor.charAt(i) != ';') { + ++i; + } + frame[frameIndex++] = Frame.OBJECT + | cw.addType(descriptor.substring(j + 1, i++)); + break; + default: + break loop; + } + } + frame[1] = frameIndex - 3; + endFrame(); + } + + /** + * Starts the visit of a stack map frame. + * + * @param offset + * the offset of the instruction to which the frame corresponds. + * @param nLocal + * the number of local variables in the frame. + * @param nStack + * the number of stack elements in the frame. + * @return the index of the next element to be written in this frame. + */ + private int startFrame(final int offset, final int nLocal, final int nStack) { + int n = 3 + nLocal + nStack; + if (frame == null || frame.length < n) { + frame = new int[n]; + } + frame[0] = offset; + frame[1] = nLocal; + frame[2] = nStack; + return 3; + } + + /** + * Checks if the visit of the current frame {@link #frame} is finished, and + * if yes, write it in the StackMapTable attribute. + */ + private void endFrame() { + if (previousFrame != null) { // do not write the first frame + if (stackMap == null) { + stackMap = new ByteVector(); + } + writeFrame(); + ++frameCount; + } + previousFrame = frame; + frame = null; + } + + /** + * Compress and writes the current frame {@link #frame} in the StackMapTable + * attribute. + */ + private void writeFrame() { + int clocalsSize = frame[1]; + int cstackSize = frame[2]; + if ((cw.version & 0xFFFF) < Opcodes.V1_6) { + stackMap.putShort(frame[0]).putShort(clocalsSize); + writeFrameTypes(3, 3 + clocalsSize); + stackMap.putShort(cstackSize); + writeFrameTypes(3 + clocalsSize, 3 + clocalsSize + cstackSize); + return; + } + int localsSize = previousFrame[1]; + int type = FULL_FRAME; + int k = 0; + int delta; + if (frameCount == 0) { + delta = frame[0]; + } else { + delta = frame[0] - previousFrame[0] - 1; + } + if (cstackSize == 0) { + k = clocalsSize - localsSize; + switch (k) { + case -3: + case -2: + case -1: + type = CHOP_FRAME; + localsSize = clocalsSize; + break; + case 0: + type = delta < 64 ? SAME_FRAME : SAME_FRAME_EXTENDED; + break; + case 1: + case 2: + case 3: + type = APPEND_FRAME; + break; + } + } else if (clocalsSize == localsSize && cstackSize == 1) { + type = delta < 63 ? SAME_LOCALS_1_STACK_ITEM_FRAME + : SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED; + } + if (type != FULL_FRAME) { + // verify if locals are the same + int l = 3; + for (int j = 0; j < localsSize; j++) { + if (frame[l] != previousFrame[l]) { + type = FULL_FRAME; + break; + } + l++; + } + } + switch (type) { + case SAME_FRAME: + stackMap.putByte(delta); + break; + case SAME_LOCALS_1_STACK_ITEM_FRAME: + stackMap.putByte(SAME_LOCALS_1_STACK_ITEM_FRAME + delta); + writeFrameTypes(3 + clocalsSize, 4 + clocalsSize); + break; + case SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED: + stackMap.putByte(SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED).putShort( + delta); + writeFrameTypes(3 + clocalsSize, 4 + clocalsSize); + break; + case SAME_FRAME_EXTENDED: + stackMap.putByte(SAME_FRAME_EXTENDED).putShort(delta); + break; + case CHOP_FRAME: + stackMap.putByte(SAME_FRAME_EXTENDED + k).putShort(delta); + break; + case APPEND_FRAME: + stackMap.putByte(SAME_FRAME_EXTENDED + k).putShort(delta); + writeFrameTypes(3 + localsSize, 3 + clocalsSize); + break; + // case FULL_FRAME: + default: + stackMap.putByte(FULL_FRAME).putShort(delta).putShort(clocalsSize); + writeFrameTypes(3, 3 + clocalsSize); + stackMap.putShort(cstackSize); + writeFrameTypes(3 + clocalsSize, 3 + clocalsSize + cstackSize); + } + } + + /** + * Writes some types of the current frame {@link #frame} into the + * StackMapTableAttribute. This method converts types from the format used + * in {@link Label} to the format used in StackMapTable attributes. In + * particular, it converts type table indexes to constant pool indexes. + * + * @param start + * index of the first type in {@link #frame} to write. + * @param end + * index of last type in {@link #frame} to write (exclusive). + */ + private void writeFrameTypes(final int start, final int end) { + for (int i = start; i < end; ++i) { + int t = frame[i]; + int d = t & Frame.DIM; + if (d == 0) { + int v = t & Frame.BASE_VALUE; + switch (t & Frame.BASE_KIND) { + case Frame.OBJECT: + stackMap.putByte(7).putShort( + cw.newClass(cw.typeTable[v].strVal1)); + break; + case Frame.UNINITIALIZED: + stackMap.putByte(8).putShort(cw.typeTable[v].intVal); + break; + default: + stackMap.putByte(v); + } + } else { + StringBuffer buf = new StringBuffer(); + d >>= 28; + while (d-- > 0) { + buf.append('['); + } + if ((t & Frame.BASE_KIND) == Frame.OBJECT) { + buf.append('L'); + buf.append(cw.typeTable[t & Frame.BASE_VALUE].strVal1); + buf.append(';'); + } else { + switch (t & 0xF) { + case 1: + buf.append('I'); + break; + case 2: + buf.append('F'); + break; + case 3: + buf.append('D'); + break; + case 9: + buf.append('Z'); + break; + case 10: + buf.append('B'); + break; + case 11: + buf.append('C'); + break; + case 12: + buf.append('S'); + break; + default: + buf.append('J'); + } + } + stackMap.putByte(7).putShort(cw.newClass(buf.toString())); + } + } + } + + private void writeFrameType(final Object type) { + if (type instanceof String) { + stackMap.putByte(7).putShort(cw.newClass((String) type)); + } else if (type instanceof Integer) { + stackMap.putByte(((Integer) type).intValue()); + } else { + stackMap.putByte(8).putShort(((Label) type).position); + } + } + + // ------------------------------------------------------------------------ + // Utility methods: dump bytecode array + // ------------------------------------------------------------------------ + + /** + * Returns the size of the bytecode of this method. + * + * @return the size of the bytecode of this method. + */ + final int getSize() { + if (classReaderOffset != 0) { + return 6 + classReaderLength; + } + if (resize) { + // replaces the temporary jump opcodes introduced by Label.resolve. + if (ClassReader.RESIZE) { + resizeInstructions(); + } else { + throw new RuntimeException("Method code too large!"); + } + } + int size = 8; + if (code.length > 0) { + if (code.length > 65536) { + throw new RuntimeException("Method code too large!"); + } + cw.newUTF8("Code"); + size += 18 + code.length + 8 * handlerCount; + if (localVar != null) { + cw.newUTF8("LocalVariableTable"); + size += 8 + localVar.length; + } + if (localVarType != null) { + cw.newUTF8("LocalVariableTypeTable"); + size += 8 + localVarType.length; + } + if (lineNumber != null) { + cw.newUTF8("LineNumberTable"); + size += 8 + lineNumber.length; + } + if (stackMap != null) { + boolean zip = (cw.version & 0xFFFF) >= Opcodes.V1_6; + cw.newUTF8(zip ? "StackMapTable" : "StackMap"); + size += 8 + stackMap.length; + } + if (cattrs != null) { + size += cattrs.getSize(cw, code.data, code.length, maxStack, + maxLocals); + } + } + if (exceptionCount > 0) { + cw.newUTF8("Exceptions"); + size += 8 + 2 * exceptionCount; + } + if ((access & Opcodes.ACC_SYNTHETIC) != 0) { + if ((cw.version & 0xFFFF) < Opcodes.V1_5 + || (access & ClassWriter.ACC_SYNTHETIC_ATTRIBUTE) != 0) { + cw.newUTF8("Synthetic"); + size += 6; + } + } + if ((access & Opcodes.ACC_DEPRECATED) != 0) { + cw.newUTF8("Deprecated"); + size += 6; + } + if (ClassReader.SIGNATURES && signature != null) { + cw.newUTF8("Signature"); + cw.newUTF8(signature); + size += 8; + } + if (ClassReader.ANNOTATIONS && annd != null) { + cw.newUTF8("AnnotationDefault"); + size += 6 + annd.length; + } + if (ClassReader.ANNOTATIONS && anns != null) { + cw.newUTF8("RuntimeVisibleAnnotations"); + size += 8 + anns.getSize(); + } + if (ClassReader.ANNOTATIONS && ianns != null) { + cw.newUTF8("RuntimeInvisibleAnnotations"); + size += 8 + ianns.getSize(); + } + if (ClassReader.ANNOTATIONS && panns != null) { + cw.newUTF8("RuntimeVisibleParameterAnnotations"); + size += 7 + 2 * (panns.length - synthetics); + for (int i = panns.length - 1; i >= synthetics; --i) { + size += panns[i] == null ? 0 : panns[i].getSize(); + } + } + if (ClassReader.ANNOTATIONS && ipanns != null) { + cw.newUTF8("RuntimeInvisibleParameterAnnotations"); + size += 7 + 2 * (ipanns.length - synthetics); + for (int i = ipanns.length - 1; i >= synthetics; --i) { + size += ipanns[i] == null ? 0 : ipanns[i].getSize(); + } + } + if (attrs != null) { + size += attrs.getSize(cw, null, 0, -1, -1); + } + return size; + } + + /** + * Puts the bytecode of this method in the given byte vector. + * + * @param out + * the byte vector into which the bytecode of this method must be + * copied. + */ + final void put(final ByteVector out) { + final int FACTOR = ClassWriter.TO_ACC_SYNTHETIC; + int mask = ACC_CONSTRUCTOR | Opcodes.ACC_DEPRECATED + | ClassWriter.ACC_SYNTHETIC_ATTRIBUTE + | ((access & ClassWriter.ACC_SYNTHETIC_ATTRIBUTE) / FACTOR); + out.putShort(access & ~mask).putShort(name).putShort(desc); + if (classReaderOffset != 0) { + out.putByteArray(cw.cr.b, classReaderOffset, classReaderLength); + return; + } + int attributeCount = 0; + if (code.length > 0) { + ++attributeCount; + } + if (exceptionCount > 0) { + ++attributeCount; + } + if ((access & Opcodes.ACC_SYNTHETIC) != 0) { + if ((cw.version & 0xFFFF) < Opcodes.V1_5 + || (access & ClassWriter.ACC_SYNTHETIC_ATTRIBUTE) != 0) { + ++attributeCount; + } + } + if ((access & Opcodes.ACC_DEPRECATED) != 0) { + ++attributeCount; + } + if (ClassReader.SIGNATURES && signature != null) { + ++attributeCount; + } + if (ClassReader.ANNOTATIONS && annd != null) { + ++attributeCount; + } + if (ClassReader.ANNOTATIONS && anns != null) { + ++attributeCount; + } + if (ClassReader.ANNOTATIONS && ianns != null) { + ++attributeCount; + } + if (ClassReader.ANNOTATIONS && panns != null) { + ++attributeCount; + } + if (ClassReader.ANNOTATIONS && ipanns != null) { + ++attributeCount; + } + if (attrs != null) { + attributeCount += attrs.getCount(); + } + out.putShort(attributeCount); + if (code.length > 0) { + int size = 12 + code.length + 8 * handlerCount; + if (localVar != null) { + size += 8 + localVar.length; + } + if (localVarType != null) { + size += 8 + localVarType.length; + } + if (lineNumber != null) { + size += 8 + lineNumber.length; + } + if (stackMap != null) { + size += 8 + stackMap.length; + } + if (cattrs != null) { + size += cattrs.getSize(cw, code.data, code.length, maxStack, + maxLocals); + } + out.putShort(cw.newUTF8("Code")).putInt(size); + out.putShort(maxStack).putShort(maxLocals); + out.putInt(code.length).putByteArray(code.data, 0, code.length); + out.putShort(handlerCount); + if (handlerCount > 0) { + Handler h = firstHandler; + while (h != null) { + out.putShort(h.start.position).putShort(h.end.position) + .putShort(h.handler.position).putShort(h.type); + h = h.next; + } + } + attributeCount = 0; + if (localVar != null) { + ++attributeCount; + } + if (localVarType != null) { + ++attributeCount; + } + if (lineNumber != null) { + ++attributeCount; + } + if (stackMap != null) { + ++attributeCount; + } + if (cattrs != null) { + attributeCount += cattrs.getCount(); + } + out.putShort(attributeCount); + if (localVar != null) { + out.putShort(cw.newUTF8("LocalVariableTable")); + out.putInt(localVar.length + 2).putShort(localVarCount); + out.putByteArray(localVar.data, 0, localVar.length); + } + if (localVarType != null) { + out.putShort(cw.newUTF8("LocalVariableTypeTable")); + out.putInt(localVarType.length + 2).putShort(localVarTypeCount); + out.putByteArray(localVarType.data, 0, localVarType.length); + } + if (lineNumber != null) { + out.putShort(cw.newUTF8("LineNumberTable")); + out.putInt(lineNumber.length + 2).putShort(lineNumberCount); + out.putByteArray(lineNumber.data, 0, lineNumber.length); + } + if (stackMap != null) { + boolean zip = (cw.version & 0xFFFF) >= Opcodes.V1_6; + out.putShort(cw.newUTF8(zip ? "StackMapTable" : "StackMap")); + out.putInt(stackMap.length + 2).putShort(frameCount); + out.putByteArray(stackMap.data, 0, stackMap.length); + } + if (cattrs != null) { + cattrs.put(cw, code.data, code.length, maxLocals, maxStack, out); + } + } + if (exceptionCount > 0) { + out.putShort(cw.newUTF8("Exceptions")).putInt( + 2 * exceptionCount + 2); + out.putShort(exceptionCount); + for (int i = 0; i < exceptionCount; ++i) { + out.putShort(exceptions[i]); + } + } + if ((access & Opcodes.ACC_SYNTHETIC) != 0) { + if ((cw.version & 0xFFFF) < Opcodes.V1_5 + || (access & ClassWriter.ACC_SYNTHETIC_ATTRIBUTE) != 0) { + out.putShort(cw.newUTF8("Synthetic")).putInt(0); + } + } + if ((access & Opcodes.ACC_DEPRECATED) != 0) { + out.putShort(cw.newUTF8("Deprecated")).putInt(0); + } + if (ClassReader.SIGNATURES && signature != null) { + out.putShort(cw.newUTF8("Signature")).putInt(2) + .putShort(cw.newUTF8(signature)); + } + if (ClassReader.ANNOTATIONS && annd != null) { + out.putShort(cw.newUTF8("AnnotationDefault")); + out.putInt(annd.length); + out.putByteArray(annd.data, 0, annd.length); + } + if (ClassReader.ANNOTATIONS && anns != null) { + out.putShort(cw.newUTF8("RuntimeVisibleAnnotations")); + anns.put(out); + } + if (ClassReader.ANNOTATIONS && ianns != null) { + out.putShort(cw.newUTF8("RuntimeInvisibleAnnotations")); + ianns.put(out); + } + if (ClassReader.ANNOTATIONS && panns != null) { + out.putShort(cw.newUTF8("RuntimeVisibleParameterAnnotations")); + AnnotationWriter.put(panns, synthetics, out); + } + if (ClassReader.ANNOTATIONS && ipanns != null) { + out.putShort(cw.newUTF8("RuntimeInvisibleParameterAnnotations")); + AnnotationWriter.put(ipanns, synthetics, out); + } + if (attrs != null) { + attrs.put(cw, null, 0, -1, -1, out); + } + } + + // ------------------------------------------------------------------------ + // Utility methods: instruction resizing (used to handle GOTO_W and JSR_W) + // ------------------------------------------------------------------------ + + /** + * Resizes and replaces the temporary instructions inserted by + * {@link Label#resolve} for wide forward jumps, while keeping jump offsets + * and instruction addresses consistent. This may require to resize other + * existing instructions, or even to introduce new instructions: for + * example, increasing the size of an instruction by 2 at the middle of a + * method can increases the offset of an IFEQ instruction from 32766 to + * 32768, in which case IFEQ 32766 must be replaced with IFNEQ 8 GOTO_W + * 32765. This, in turn, may require to increase the size of another jump + * instruction, and so on... All these operations are handled automatically + * by this method. + * <p> + * <i>This method must be called after all the method that is being built + * has been visited</i>. In particular, the {@link Label Label} objects used + * to construct the method are no longer valid after this method has been + * called. + */ + private void resizeInstructions() { + byte[] b = code.data; // bytecode of the method + int u, v, label; // indexes in b + int i, j; // loop indexes + /* + * 1st step: As explained above, resizing an instruction may require to + * resize another one, which may require to resize yet another one, and + * so on. The first step of the algorithm consists in finding all the + * instructions that need to be resized, without modifying the code. + * This is done by the following "fix point" algorithm: + * + * Parse the code to find the jump instructions whose offset will need + * more than 2 bytes to be stored (the future offset is computed from + * the current offset and from the number of bytes that will be inserted + * or removed between the source and target instructions). For each such + * instruction, adds an entry in (a copy of) the indexes and sizes + * arrays (if this has not already been done in a previous iteration!). + * + * If at least one entry has been added during the previous step, go + * back to the beginning, otherwise stop. + * + * In fact the real algorithm is complicated by the fact that the size + * of TABLESWITCH and LOOKUPSWITCH instructions depends on their + * position in the bytecode (because of padding). In order to ensure the + * convergence of the algorithm, the number of bytes to be added or + * removed from these instructions is over estimated during the previous + * loop, and computed exactly only after the loop is finished (this + * requires another pass to parse the bytecode of the method). + */ + int[] allIndexes = new int[0]; // copy of indexes + int[] allSizes = new int[0]; // copy of sizes + boolean[] resize; // instructions to be resized + int newOffset; // future offset of a jump instruction + + resize = new boolean[code.length]; + + // 3 = loop again, 2 = loop ended, 1 = last pass, 0 = done + int state = 3; + do { + if (state == 3) { + state = 2; + } + u = 0; + while (u < b.length) { + int opcode = b[u] & 0xFF; // opcode of current instruction + int insert = 0; // bytes to be added after this instruction + + switch (ClassWriter.TYPE[opcode]) { + case ClassWriter.NOARG_INSN: + case ClassWriter.IMPLVAR_INSN: + u += 1; + break; + case ClassWriter.LABEL_INSN: + if (opcode > 201) { + // converts temporary opcodes 202 to 217, 218 and + // 219 to IFEQ ... JSR (inclusive), IFNULL and + // IFNONNULL + opcode = opcode < 218 ? opcode - 49 : opcode - 20; + label = u + readUnsignedShort(b, u + 1); + } else { + label = u + readShort(b, u + 1); + } + newOffset = getNewOffset(allIndexes, allSizes, u, label); + if (newOffset < Short.MIN_VALUE + || newOffset > Short.MAX_VALUE) { + if (!resize[u]) { + if (opcode == Opcodes.GOTO || opcode == Opcodes.JSR) { + // two additional bytes will be required to + // replace this GOTO or JSR instruction with + // a GOTO_W or a JSR_W + insert = 2; + } else { + // five additional bytes will be required to + // replace this IFxxx <l> instruction with + // IFNOTxxx <l'> GOTO_W <l>, where IFNOTxxx + // is the "opposite" opcode of IFxxx (i.e., + // IFNE for IFEQ) and where <l'> designates + // the instruction just after the GOTO_W. + insert = 5; + } + resize[u] = true; + } + } + u += 3; + break; + case ClassWriter.LABELW_INSN: + u += 5; + break; + case ClassWriter.TABL_INSN: + if (state == 1) { + // true number of bytes to be added (or removed) + // from this instruction = (future number of padding + // bytes - current number of padding byte) - + // previously over estimated variation = + // = ((3 - newOffset%4) - (3 - u%4)) - u%4 + // = (-newOffset%4 + u%4) - u%4 + // = -(newOffset & 3) + newOffset = getNewOffset(allIndexes, allSizes, 0, u); + insert = -(newOffset & 3); + } else if (!resize[u]) { + // over estimation of the number of bytes to be + // added to this instruction = 3 - current number + // of padding bytes = 3 - (3 - u%4) = u%4 = u & 3 + insert = u & 3; + resize[u] = true; + } + // skips instruction + u = u + 4 - (u & 3); + u += 4 * (readInt(b, u + 8) - readInt(b, u + 4) + 1) + 12; + break; + case ClassWriter.LOOK_INSN: + if (state == 1) { + // like TABL_INSN + newOffset = getNewOffset(allIndexes, allSizes, 0, u); + insert = -(newOffset & 3); + } else if (!resize[u]) { + // like TABL_INSN + insert = u & 3; + resize[u] = true; + } + // skips instruction + u = u + 4 - (u & 3); + u += 8 * readInt(b, u + 4) + 8; + break; + case ClassWriter.WIDE_INSN: + opcode = b[u + 1] & 0xFF; + if (opcode == Opcodes.IINC) { + u += 6; + } else { + u += 4; + } + break; + case ClassWriter.VAR_INSN: + case ClassWriter.SBYTE_INSN: + case ClassWriter.LDC_INSN: + u += 2; + break; +
<TRUNCATED>
