/*
* @(#)AssignOpExpression.java 1.18 95/10/03 Arthur van Hoff
*
* Copyright (c) 1994 Sun Microsystems, Inc. All Rights Reserved.
*
* Permission to use, copy, modify, and distribute this software
* and its documentation for NON-COMMERCIAL purposes and without
* fee is hereby granted provided that this copyright notice
* appears in all copies. Please refer to the file "copyright.html"
* for further important copyright and licensing information.
*
* SUN MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF
* THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
* TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE, OR NON-INFRINGEMENT. SUN SHALL NOT BE LIABLE FOR
* ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
* DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES.
*/
package sun.tools.tree;
import sun.tools.java.*;
import sun.tools.asm.Assembler;
import java.io.PrintStream;
import java.util.Hashtable;
public
class AssignOpExpression extends BinaryAssignExpression {
final int NOINC = Integer.MAX_VALUE;
/**
* Constructor
*/
public AssignOpExpression(int op, int where, Expression left, Expression right) {
super(op, where, left, right);
}
/**
* Get the increment, return NOINC if an increment is not possible
*/
int getIncrement() {
if ((left.op == IDENT) && type.isType(TC_INT) && (right.op == INTVAL))
if ((op == ASGADD) || (op == ASGSUB))
if (((IdentifierExpression)left).field.isLocal()) {
int val = ((IntExpression)right).value;
if (op == ASGSUB)
val = -val;
if (val == (short)val)
return val;
}
return NOINC;
}
/**
* Check an assignment expression
*/
public long checkValue(Environment env, Context ctx, long vset, Hashtable exp) {
vset = left.checkAssignOp(env, ctx, vset, exp, this);
vset = right.checkValue(env, ctx, vset, exp);
selectType(env, ctx,
left.type.getTypeMask() | right.type.getTypeMask());
if (!type.isType(TC_ERROR)) {
convert(env, ctx, type, left);
}
return vset;
}
/**
* Inline
*/
public Expression inlineValue(Environment env, Context ctx) {
left = left.inlineValue(env, ctx);
right = right.inlineValue(env, ctx);
return this;
}
/**
* Create a copy of the expression for method inlining
*/
public Expression copyInline(Context ctx) {
AssignOpExpression e = (AssignOpExpression)clone();
e.left = left.copyInline(ctx);
e.right = right.copyInline(ctx);
return e;
}
/**
* The cost of inlining this statement
*/
public int costInline(int thresh) {
return (getIncrement() != NOINC) ? 2 : 3 + super.costInline(thresh);
}
/**
* Code
*/
void code(Environment env, Context ctx, Assembler asm, boolean valNeeded) {
int val = getIncrement();
if (val != NOINC) {
int v = ((LocalField)((IdentifierExpression)left).field).number;
int[] operands = { v, val };
asm.add(where, opc_iinc, operands);
if (valNeeded) {
left.codeValue(env, ctx, asm);
}
return;
}
int depth = left.codeLValue(env, ctx, asm);
codeDup(env, ctx, asm, depth, 0);
left.codeLoad(env, ctx, asm);
codeConversion(env, ctx, asm, left.type, type);
right.codeValue(env, ctx, asm);
codeOperation(env, ctx, asm);
codeConversion(env, ctx, asm, type, left.type);
if (valNeeded) {
codeDup(env, ctx, asm, type.stackSize(), depth);
}
left.codeStore(env, ctx, asm);
}
public void codeValue(Environment env, Context ctx, Assembler asm) {
code(env, ctx, asm, true);
}
public void code(Environment env, Context ctx, Assembler asm) {
code(env, ctx, asm, false);
}
/**
* Print
*/
public void print(PrintStream out) {
out.print("(" + opNames[op] + " ");
left.print(out);
out.print(" ");
right.print(out);
out.print(")");
}
}