compiler/src/main/java/org/apache/royale/abc/semantics/MethodBodyInfo.java - royale-compiler - Git at Google

 /*
  *
  *  Licensed to the Apache Software Foundation (ASF) under one or more
  *  contributor license agreements.  See the NOTICE file distributed with
  *  this work for additional information regarding copyright ownership.
  *  The ASF licenses this file to You under the Apache License, Version 2.0
  *  (the "License"); you may not use this file except in compliance with
  *  the License.  You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  *  Unless required by applicable law or agreed to in writing, software
  *  distributed under the License is distributed on an "AS IS" BASIS,
  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *  See the License for the specific language governing permissions and
  *  limitations under the License.
  *
  */

 package org.apache.royale.abc.semantics;

 import java.util.Collections;
 import java.util.List;
 import java.util.Vector;

 import org.apache.royale.abc.graph.IBasicBlock;
 import org.apache.royale.abc.graph.IFlowgraph;
 import org.apache.royale.abc.instructionlist.InstructionList;
 import org.apache.royale.abc.visitors.IDiagnosticsVisitor;

 import static org.apache.royale.abc.ABCConstants.*;

 /**
  * A representation of a method's <a href="http://learn.adobe.com/wiki/display/AVM2/4.11+Method+body">method body information</a>.
  */
 public class MethodBodyInfo
 {
     /**
      * Construct a new MethodBodyInfo.
      */
     public MethodBodyInfo()
     {
     }

     MethodInfo methodInfo;

     public int max_stack;
     public int max_scope;
     public int initial_scope;
     public int max_local;
     public int max_slot;
     public int code_len;

     Integer explicit_max_stack;
     Integer explicit_init_scope;
     Integer explicit_max_scope;
     Integer explicit_max_local;
     Integer explicit_max_slot;

     Traits traits = new Traits();

     /**
      * Does this method body contain a newclass instruction? Higher-level code
      * needs to know this because the ABC may have its class info structures
      * sorted into dependency order, which would invalidate the index in the
      * newclass instruction if the method body were serialized to bytecode.
      */
     private boolean hasNewclass = false;

     private Vector<ExceptionInfo> exceptions = new Vector<ExceptionInfo>();

     /**
      * The method's instructions as a simple list.
      */
     InstructionList instructions = new InstructionList();

     /**
      * The method's control flow graph. The ControlFlowGraph is only available
      * and valid when the method's instructions are in their deserialized form.
      */
     IFlowgraph cfg = null;

     /**
      * The method's instructions after being converted into ABC bytecode.
      */
     byte[] bytecode = null;

     public MethodInfo getMethodInfo()
     {
         return this.methodInfo;
     }

     public void setMethodInfo(MethodInfo minfo)
     {
         this.methodInfo = minfo;
     }

     /**
      * @return the method's traits.
      */
     public Traits getTraits()
     {
         return traits;
     }

     /**
      * Set the method's traits.
      *
      * @param t - the method's traits.
      */
     public void setTraits(Traits t)
     {
         this.traits = t;
     }

     /**
      * Set this method's serialized ABC.
      *
      * @param bytecode - the method's instructions serialized to ABC bytecode.
      * @post the method's InstructionList based bytecode is no longer available.
      */
     public void setBytecode(final byte[] bytecode)
     {
         this.bytecode = bytecode;
         this.instructions = null;
         this.cfg = null;
     }

     /**
      * Retrieve this method's bytecode.
      *
      * @return previously serialized bytecode.
      * @pre setBytecode() called to store the bytecode.
      */
     public byte[] getBytecode()
     {
         assert this.bytecode != null;
         return this.bytecode;
     }

     /**
      * Has this method been serialized to bytecode?
      *
      * @return true if the method's serialized bytecode is set.
      */
     public boolean hasBytecode()
     {
         return this.bytecode != null;
     }

     /**
      * Get the method's control flow graph, building it as necessary.
      *
      * @return the method's control flow graph.
      * @pre the method must not have been serialized to ABC.
      */
     public IFlowgraph getCfg()
     {
         if (null == this.cfg)
             rebuildCfg();

         return this.cfg;
     }

     /**
      * Rebuild the control flow graph.
      */
     private void rebuildCfg()
     {
         //  Note that it would be possible to deserialize the method and then construct a CFG.
         assert instructions != null : "Unable to build control flow graph after serialization to ABC";
         this.cfg = new ControlFlowGraph(this);
     }

     public Instruction insn(int opcode)
     {
         return this.instructions.addInstruction(opcode);
     }

     public Instruction insn(int opcode, Object[] operands)
     {
         Instruction result = InstructionFactory.getInstruction(opcode, operands);
         this.instructions.addInstruction(result);
         return result;
     }

     public Instruction insn(int opcode, Object pooledValue)
     {
         Instruction i = InstructionFactory.getInstruction(opcode, pooledValue);
         this.instructions.addInstruction(i);
         return i;
     }

     public Instruction insn(int opcode, int immed)
     {
         Instruction i = InstructionFactory.getInstruction(opcode, immed);
         this.instructions.addInstruction(i);
         return i;
     }

     public void insn(Instruction instruction)
     {
         this.instructions.addInstruction(instruction);
     }

     /**
      * Compute a functions's max_stack, max_scope, and slot count.
      *
      * @note noop if all counts were explicitly provided.
      */
     public void computeFrameCounts(IDiagnosticsVisitor diagnosticsVisitor)
     {
         if (this.explicit_max_stack != null && this.explicit_max_scope != null && this.explicit_max_local != null && this.explicit_max_slot != null)
         {
             //  All counts explicitly provided.
             return;
         }

         FrameCountVisitor counts = new FrameCountVisitor(this, diagnosticsVisitor, this.initial_scope);
         getCfg().traverseGraph(counts);

         // Grrr..  TODO when we tighten up the max_stack,
         // max_scope, etc for code we read out of the flex
         // framework we seem to break that code.
         // For now, never let the max_stack, etc go down.
         this.max_stack = Math.max(counts.max_stack, this.max_stack);
         this.max_scope = Math.max(counts.max_scope, this.max_scope);
         this.max_local = Math.max(counts.max_local, this.max_local);
         this.max_slot = Math.max(counts.max_slot, this.max_slot);
         this.hasNewclass |= counts.hasNewclassInstruction();
     }

     public int getMaxStack()
     {
         if (explicit_max_stack != null)
             return explicit_max_stack;
         else
             return max_stack;
     }

     public int getLocalCount()
     {
         if (explicit_max_local != null)
             return explicit_max_local;
         else if ((this.methodInfo.getFlags() & NEED_REST) != 0)
             return max_local + 1;
         else
             return max_local;
     }

     public int getMaxSlotCount()
     {
         if (explicit_max_slot != null)
             return explicit_max_slot;
         else if (max_slot < traits.getTraitCount())
             return traits.getTraitCount();
         else
             return max_slot;
     }

     public int getMaxScopeDepth()
     {
         if (explicit_max_scope != null)
             return explicit_max_scope;
         else
             return max_scope;
     }

     public int addExceptionInfo(ExceptionInfo ex)
     {
         this.exceptions.add(ex);
         return this.exceptions.size() - 1; //  zero-based exception numbers
     }

     public int getInitScopeDepth()
     {
         if (this.explicit_init_scope != null)
             return explicit_init_scope;
         else
             return this.initial_scope;
     }

     /**
      * Get the block that the label corresponds to. Will throw an
      * IllegalArgumentException if the label does not correspond to any known
      * block.
      *
      * @param target the label you want the block for
      * @return the block that the label refers to.
      */
     public IBasicBlock getBlock(Label target)
     {
         return getBlock(target, true);
     }

     /**
      * Get the block that the label corresponds to. Will throw an
      * IllegalArgumentException if the label does not correspond to any known
      * block, and throwOnError is true.
      *
      * @param target the label you want the block for
      * @param throwOnError false if you do not want this method to throw an
      * IllegalArgumentException - in this case the method will return null
      * instead.
      * @return the block that the label refers to.
      */
     public IBasicBlock getBlock(Label target, boolean throwOnError)
     {
         IBasicBlock result = cfg.getBlock(target);

         if (result == null && throwOnError)
             throw new IllegalArgumentException("Label " + target.toString() + " was referenced, but never defined.");

         return result;
     }

     /**
      * @return exception handlers defined in this method.
      */
     public List<ExceptionInfo> getExceptions()
     {
         if (this.exceptions != null)
             return exceptions;
         else
             return Collections.emptyList();
     }

     /**
      * Does the given Label reference a catch target?
      * @param l - the Label of interest.
      * @return true if the Label references a catch target,
      *   either by identity or by position.
      */
     public boolean isCatchTarget(Label l)
     {
         for (ExceptionInfo e : exceptions)
         {
             Label target = e.getTarget();
             if ( l.getPosition() == target.getPosition() || l == target )
                 return true;
         }
         return false;
     }

     /**
      * Set this method body's InstructionList. Used by code generators that
      * build up an InstructionList from smaller parts; not relevant if the
      * InstructionList is built by visitInstruction() calls on this object.
      */
     public void setInstructionList(InstructionList new_list)
     {
         this.instructions = new_list;

         if (this.cfg != null)
             rebuildCfg();
     }

     /**
      * @return this method body's InstructionList.
      */
     public InstructionList getInstructionList()
     {
         assert (this.instructions != null) : "No active InstructionList";
         return this.instructions;
     }

     /**
      * Pass through a labelCurrent() request to the resident InstructionList.
      */
     public void labelCurrent(Label l)
     {
         assert (this.instructions != null) : "No active InstructionList";
         this.instructions.labelCurrent(l);
     }

     /**
      * Pass through a labelNext() request to the resident InstructionList.
      */
     public void labelNext(Label l)
     {
         assert (this.instructions != null) : "No active InstructionList";
         this.instructions.labelNext(l);
     }

     /**
      * Does this method body contain a newclass instruction?
      *
      * @pre computeFrameCounts() must have been called.
      */
     public boolean hasNewclassInstruction()
     {
         return this.hasNewclass;
     }
 }
	/*
	*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to You under the Apache License, Version 2.0
	* (the "License"); you may not use this file except in compliance with
	* the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*
	*/

	package org.apache.royale.abc.semantics;

	import java.util.Collections;
	import java.util.List;
	import java.util.Vector;

	import org.apache.royale.abc.graph.IBasicBlock;
	import org.apache.royale.abc.graph.IFlowgraph;
	import org.apache.royale.abc.instructionlist.InstructionList;
	import org.apache.royale.abc.visitors.IDiagnosticsVisitor;

	import static org.apache.royale.abc.ABCConstants.*;

	/**
	* A representation of a method's <a href="http://learn.adobe.com/wiki/display/AVM2/4.11+Method+body">method body information</a>.
	*/
	public class MethodBodyInfo
	{
	/**
	* Construct a new MethodBodyInfo.
	*/
	public MethodBodyInfo()
	{
	}

	MethodInfo methodInfo;

	public int max_stack;
	public int max_scope;
	public int initial_scope;
	public int max_local;
	public int max_slot;
	public int code_len;

	Integer explicit_max_stack;
	Integer explicit_init_scope;
	Integer explicit_max_scope;
	Integer explicit_max_local;
	Integer explicit_max_slot;

	Traits traits = new Traits();

	/**
	* Does this method body contain a newclass instruction? Higher-level code
	* needs to know this because the ABC may have its class info structures
	* sorted into dependency order, which would invalidate the index in the
	* newclass instruction if the method body were serialized to bytecode.
	*/
	private boolean hasNewclass = false;

	private Vector<ExceptionInfo> exceptions = new Vector<ExceptionInfo>();

	/**
	* The method's instructions as a simple list.
	*/
	InstructionList instructions = new InstructionList();

	/**
	* The method's control flow graph. The ControlFlowGraph is only available
	* and valid when the method's instructions are in their deserialized form.
	*/
	IFlowgraph cfg = null;

	/**
	* The method's instructions after being converted into ABC bytecode.
	*/
	byte[] bytecode = null;

	public MethodInfo getMethodInfo()
	{
	return this.methodInfo;
	}

	public void setMethodInfo(MethodInfo minfo)
	{
	this.methodInfo = minfo;
	}

	/**
	* @return the method's traits.
	*/
	public Traits getTraits()
	{
	return traits;
	}

	/**
	* Set the method's traits.
	*
	* @param t - the method's traits.
	*/
	public void setTraits(Traits t)
	{
	this.traits = t;
	}

	/**
	* Set this method's serialized ABC.
	*
	* @param bytecode - the method's instructions serialized to ABC bytecode.
	* @post the method's InstructionList based bytecode is no longer available.
	*/
	public void setBytecode(final byte[] bytecode)
	{
	this.bytecode = bytecode;
	this.instructions = null;
	this.cfg = null;
	}

	/**
	* Retrieve this method's bytecode.
	*
	* @return previously serialized bytecode.
	* @pre setBytecode() called to store the bytecode.
	*/
	public byte[] getBytecode()
	{
	assert this.bytecode != null;
	return this.bytecode;
	}

	/**
	* Has this method been serialized to bytecode?
	*
	* @return true if the method's serialized bytecode is set.
	*/
	public boolean hasBytecode()
	{
	return this.bytecode != null;
	}

	/**
	* Get the method's control flow graph, building it as necessary.
	*
	* @return the method's control flow graph.
	* @pre the method must not have been serialized to ABC.
	*/
	public IFlowgraph getCfg()
	{
	if (null == this.cfg)
	rebuildCfg();

	return this.cfg;
	}

	/**
	* Rebuild the control flow graph.
	*/
	private void rebuildCfg()
	{
	// Note that it would be possible to deserialize the method and then construct a CFG.
	assert instructions != null : "Unable to build control flow graph after serialization to ABC";
	this.cfg = new ControlFlowGraph(this);
	}

	public Instruction insn(int opcode)
	{
	return this.instructions.addInstruction(opcode);
	}

	public Instruction insn(int opcode, Object[] operands)
	{
	Instruction result = InstructionFactory.getInstruction(opcode, operands);
	this.instructions.addInstruction(result);
	return result;
	}

	public Instruction insn(int opcode, Object pooledValue)
	{
	Instruction i = InstructionFactory.getInstruction(opcode, pooledValue);
	this.instructions.addInstruction(i);
	return i;
	}

	public Instruction insn(int opcode, int immed)
	{
	Instruction i = InstructionFactory.getInstruction(opcode, immed);
	this.instructions.addInstruction(i);
	return i;
	}

	public void insn(Instruction instruction)
	{
	this.instructions.addInstruction(instruction);
	}

	/**
	* Compute a functions's max_stack, max_scope, and slot count.
	*
	* @note noop if all counts were explicitly provided.
	*/
	public void computeFrameCounts(IDiagnosticsVisitor diagnosticsVisitor)
	{
	if (this.explicit_max_stack != null && this.explicit_max_scope != null && this.explicit_max_local != null && this.explicit_max_slot != null)
	{
	// All counts explicitly provided.
	return;
	}

	FrameCountVisitor counts = new FrameCountVisitor(this, diagnosticsVisitor, this.initial_scope);
	getCfg().traverseGraph(counts);

	// Grrr.. TODO when we tighten up the max_stack,
	// max_scope, etc for code we read out of the flex
	// framework we seem to break that code.
	// For now, never let the max_stack, etc go down.
	this.max_stack = Math.max(counts.max_stack, this.max_stack);
	this.max_scope = Math.max(counts.max_scope, this.max_scope);
	this.max_local = Math.max(counts.max_local, this.max_local);
	this.max_slot = Math.max(counts.max_slot, this.max_slot);
	this.hasNewclass \|= counts.hasNewclassInstruction();
	}

	public int getMaxStack()
	{
	if (explicit_max_stack != null)
	return explicit_max_stack;
	else
	return max_stack;
	}

	public int getLocalCount()
	{
	if (explicit_max_local != null)
	return explicit_max_local;
	else if ((this.methodInfo.getFlags() & NEED_REST) != 0)
	return max_local + 1;
	else
	return max_local;
	}

	public int getMaxSlotCount()
	{
	if (explicit_max_slot != null)
	return explicit_max_slot;
	else if (max_slot < traits.getTraitCount())
	return traits.getTraitCount();
	else
	return max_slot;
	}

	public int getMaxScopeDepth()
	{
	if (explicit_max_scope != null)
	return explicit_max_scope;
	else
	return max_scope;
	}

	public int addExceptionInfo(ExceptionInfo ex)
	{
	this.exceptions.add(ex);
	return this.exceptions.size() - 1; // zero-based exception numbers
	}

	public int getInitScopeDepth()
	{
	if (this.explicit_init_scope != null)
	return explicit_init_scope;
	else
	return this.initial_scope;
	}

	/**
	* Get the block that the label corresponds to. Will throw an
	* IllegalArgumentException if the label does not correspond to any known
	* block.
	*
	* @param target the label you want the block for
	* @return the block that the label refers to.
	*/
	public IBasicBlock getBlock(Label target)
	{
	return getBlock(target, true);
	}

	/**
	* Get the block that the label corresponds to. Will throw an
	* IllegalArgumentException if the label does not correspond to any known
	* block, and throwOnError is true.
	*
	* @param target the label you want the block for
	* @param throwOnError false if you do not want this method to throw an
	* IllegalArgumentException - in this case the method will return null
	* instead.
	* @return the block that the label refers to.
	*/
	public IBasicBlock getBlock(Label target, boolean throwOnError)
	{
	IBasicBlock result = cfg.getBlock(target);

	if (result == null && throwOnError)
	throw new IllegalArgumentException("Label " + target.toString() + " was referenced, but never defined.");

	return result;
	}

	/**
	* @return exception handlers defined in this method.
	*/
	public List<ExceptionInfo> getExceptions()
	{
	if (this.exceptions != null)
	return exceptions;
	else
	return Collections.emptyList();
	}

	/**
	* Does the given Label reference a catch target?
	* @param l - the Label of interest.
	* @return true if the Label references a catch target,
	* either by identity or by position.
	*/
	public boolean isCatchTarget(Label l)
	{
	for (ExceptionInfo e : exceptions)
	{
	Label target = e.getTarget();
	if ( l.getPosition() == target.getPosition() \|\| l == target )
	return true;
	}
	return false;
	}

	/**
	* Set this method body's InstructionList. Used by code generators that
	* build up an InstructionList from smaller parts; not relevant if the
	* InstructionList is built by visitInstruction() calls on this object.
	*/
	public void setInstructionList(InstructionList new_list)
	{
	this.instructions = new_list;

	if (this.cfg != null)
	rebuildCfg();
	}

	/**
	* @return this method body's InstructionList.
	*/
	public InstructionList getInstructionList()
	{
	assert (this.instructions != null) : "No active InstructionList";
	return this.instructions;
	}

	/**
	* Pass through a labelCurrent() request to the resident InstructionList.
	*/
	public void labelCurrent(Label l)
	{
	assert (this.instructions != null) : "No active InstructionList";
	this.instructions.labelCurrent(l);
	}

	/**
	* Pass through a labelNext() request to the resident InstructionList.
	*/
	public void labelNext(Label l)
	{
	assert (this.instructions != null) : "No active InstructionList";
	this.instructions.labelNext(l);
	}

	/**
	* Does this method body contain a newclass instruction?
	*
	* @pre computeFrameCounts() must have been called.
	*/
	public boolean hasNewclassInstruction()
	{
	return this.hasNewclass;
	}
	}