Add method for deleting MethodNode arguments

master
Graham 5 years ago
parent 44ddde296f
commit 23a85fd820
  1. 135
      asm/src/main/java/dev/openrs2/asm/MethodNodeUtils.java

@ -0,0 +1,135 @@
package dev.openrs2.asm;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.stream.Collectors;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Type;
import org.objectweb.asm.tree.AbstractInsnNode;
import org.objectweb.asm.tree.AnnotationNode;
import org.objectweb.asm.tree.FrameNode;
import org.objectweb.asm.tree.IincInsnNode;
import org.objectweb.asm.tree.MethodNode;
import org.objectweb.asm.tree.VarInsnNode;
public final class MethodNodeUtils {
private static int localIndex(int access, List<Type> argTypes, int argIndex) {
var localIndex = 0;
if ((access & Opcodes.ACC_STATIC) == 0) {
localIndex++;
}
for (int i = 0; i < argIndex; i++) {
localIndex += argTypes.get(i).getSize();
}
return localIndex;
}
private static int remap(int i, Type argType, int localIndex) {
if (i >= localIndex) {
return i - argType.getSize();
}
return i;
}
private static List<Integer> remapAll(List<Integer> indexes, Type argType, int localIndex) {
return indexes.stream()
.map(i -> remap(i, argType, localIndex))
.collect(Collectors.toList());
}
public static void deleteArgument(MethodNode method, int argIndex) {
/* remove argument from the signature */
var type = Type.getType(method.desc);
var argTypes = new ArrayList<>(Arrays.asList(type.getArgumentTypes()));
var argType = argTypes.remove(argIndex);
method.desc = Type.getMethodDescriptor(type.getReturnType(), argTypes.toArray(Type[]::new));
if (method.signature != null) {
throw new UnsupportedOperationException("Signatures unsupported");
}
/* calculate index of the local we're removing */
var localIndex = localIndex(method.access, argTypes, argIndex);
/* remove ParameterNode */
if (method.parameters != null) {
method.parameters.remove(argIndex);
}
/* remove annotations */
if (method.visibleAnnotableParameterCount != 0) {
throw new UnsupportedOperationException("Non-zero visibleAnnotableParameterCount unsupported");
}
if (method.visibleParameterAnnotations != null) {
@SuppressWarnings("unchecked")
var annotations = (List<AnnotationNode>[]) new List<?>[method.visibleParameterAnnotations.length - 1];
System.arraycopy(method.visibleParameterAnnotations, 0, annotations, 0, argIndex);
System.arraycopy(method.visibleParameterAnnotations, argIndex + 1, annotations, argIndex, method.visibleParameterAnnotations.length - argIndex - 1);
method.visibleParameterAnnotations = annotations;
}
if (method.invisibleAnnotableParameterCount != 0) {
throw new UnsupportedOperationException("Non-zero invisibleAnnotableParameterCount unsupported");
}
if (method.invisibleParameterAnnotations != null) {
@SuppressWarnings("unchecked")
var annotations = (List<AnnotationNode>[]) new List<?>[method.invisibleParameterAnnotations.length - 1];
System.arraycopy(method.invisibleParameterAnnotations, 0, annotations, 0, argIndex);
System.arraycopy(method.invisibleParameterAnnotations, argIndex + 1, annotations, argIndex, method.invisibleParameterAnnotations.length - argIndex - 1);
method.invisibleParameterAnnotations = annotations;
}
/* reduce maxLocals */
method.maxLocals -= argType.getSize();
/* remap locals */
if (method.localVariables != null) {
method.localVariables.removeIf(v -> v.index == localIndex);
method.localVariables.forEach(v -> v.index = remap(v.index, argType, localIndex));
}
if (method.visibleLocalVariableAnnotations != null) {
method.visibleLocalVariableAnnotations.removeIf(v -> v.index.contains(localIndex));
method.visibleLocalVariableAnnotations.forEach(v -> v.index = remapAll(v.index, argType, localIndex));
}
if (method.invisibleLocalVariableAnnotations != null) {
method.invisibleLocalVariableAnnotations.removeIf(v -> v.index.contains(localIndex));
method.invisibleLocalVariableAnnotations.forEach(v -> v.index = remapAll(v.index, argType, localIndex));
}
for (var it = method.instructions.iterator(); it.hasNext(); ) {
var insn = it.next();
switch (insn.getType()) {
case AbstractInsnNode.VAR_INSN:
var varInsn = (VarInsnNode) insn;
varInsn.var = remap(varInsn.var, argType, localIndex);
break;
case AbstractInsnNode.IINC_INSN:
var iincInsn = (IincInsnNode) insn;
iincInsn.var = remap(iincInsn.var, argType, localIndex);
break;
case AbstractInsnNode.FRAME:
var frame = (FrameNode) insn;
if (frame.type != Opcodes.F_NEW) {
throw new UnsupportedOperationException("Only F_NEW frames are supported");
}
for (int i = 0; i < argType.getSize(); i++) {
frame.local.remove(localIndex);
}
break;
}
}
}
private MethodNodeUtils() {
/* empty */
}
}
Loading…
Cancel
Save