/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package sun.tools.tree;
import sun.tools.java.*;
import sun.tools.asm.Assembler;
import java.util.Hashtable;
/**
* WARNING: The contents of this source file are not part of any
* supported API. Code that depends on them does so at its own risk:
* they are subject to change or removal without notice.
*/
public
class IncDecExpression extends UnaryExpression {
private FieldUpdater updater = null;
/**
* Constructor
*/
public IncDecExpression(int op, long where, Expression right) {
super(op, where, right.type, right);
}
/**
* Check an increment or decrement expression
*/
public Vset checkValue(Environment env, Context ctx, Vset vset, Hashtable exp) {
vset = right.checkAssignOp(env, ctx, vset, exp, this);
if (right.type.inMask(TM_NUMBER)) {
type = right.type;
} else {
if (!right.type.isType(TC_ERROR)) {
env.error(where, "invalid.arg.type", right.type, opNames[op]);
}
type = Type.tError;
}
updater = right.getUpdater(env, ctx); // Must be called after 'checkAssignOp'.
return vset;
}
/**
* Check void expression
*/
public Vset check(Environment env, Context ctx, Vset vset, Hashtable exp) {
return checkValue(env, ctx, vset, exp);
}
/**
* Inline
*/
public Expression inline(Environment env, Context ctx) {
return inlineValue(env, ctx);
}
public Expression inlineValue(Environment env, Context ctx) {
// Why not inlineLHS? But that does not work.
right = right.inlineValue(env, ctx);
if (updater != null) {
updater = updater.inline(env, ctx);
}
return this;
}
public int costInline(int thresh, Environment env, Context ctx) {
if (updater == null) {
if ((right.op == IDENT) && type.isType(TC_INT) &&
(((IdentifierExpression)right).field.isLocal())) {
// Increment variable in place. Count 3 bytes for 'iinc'.
return 3;
}
// Cost to load lhs reference, fetch local, increment, and store.
// Load/store cost will be higher if variable is a field. Note that
// costs are highly approximate. See 'AssignOpExpression.costInline'
// Does not account for cost of conversions,or duplications in
// value-needed context..
return right.costInline(thresh, env, ctx) + 4;
} else {
// Cost of two access method calls (get/set) + cost of increment.
return updater.costInline(thresh, env, ctx, true) + 1;
}
}
/**
* Code
*/
private void codeIncDecOp(Assembler asm, boolean inc) {
switch (type.getTypeCode()) {
case TC_BYTE:
asm.add(where, opc_ldc, new Integer(1));
asm.add(where, inc ? opc_iadd : opc_isub);
asm.add(where, opc_i2b);
break;
case TC_SHORT:
asm.add(where, opc_ldc, new Integer(1));
asm.add(where, inc ? opc_iadd : opc_isub);
asm.add(where, opc_i2s);
break;
case TC_CHAR:
asm.add(where, opc_ldc, new Integer(1));
asm.add(where, inc ? opc_iadd : opc_isub);
asm.add(where, opc_i2c);
break;
case TC_INT:
asm.add(where, opc_ldc, new Integer(1));
asm.add(where, inc ? opc_iadd : opc_isub);
break;
case TC_LONG:
asm.add(where, opc_ldc2_w, new Long(1));
asm.add(where, inc ? opc_ladd : opc_lsub);
break;
case TC_FLOAT:
asm.add(where, opc_ldc, new Float(1));
asm.add(where, inc ? opc_fadd : opc_fsub);
break;
case TC_DOUBLE:
asm.add(where, opc_ldc2_w, new Double(1));
asm.add(where, inc ? opc_dadd : opc_dsub);
break;
default:
throw new CompilerError("invalid type");
}
}
void codeIncDec(Environment env, Context ctx, Assembler asm, boolean inc, boolean prefix, boolean valNeeded) {
// The 'iinc' instruction cannot be used if an access method call is required.
if ((right.op == IDENT) && type.isType(TC_INT) &&
(((IdentifierExpression)right).field.isLocal()) && updater == null) {
if (valNeeded && !prefix) {
right.codeLoad(env, ctx, asm);
}
int v = ((LocalMember)((IdentifierExpression)right).field).number;
int[] operands = { v, inc ? 1 : -1 };
asm.add(where, opc_iinc, operands);
if (valNeeded && prefix) {
right.codeLoad(env, ctx, asm);
}
return;
}
if (updater == null) {
// Field is directly accessible.
int depth = right.codeLValue(env, ctx, asm);
codeDup(env, ctx, asm, depth, 0);
right.codeLoad(env, ctx, asm);
if (valNeeded && !prefix) {
codeDup(env, ctx, asm, type.stackSize(), depth);
}
codeIncDecOp(asm, inc);
if (valNeeded && prefix) {
codeDup(env, ctx, asm, type.stackSize(), depth);
}
right.codeStore(env, ctx, asm);
} else {
// Must use access methods.
updater.startUpdate(env, ctx, asm, (valNeeded && !prefix));
codeIncDecOp(asm, inc);
updater.finishUpdate(env, ctx, asm, (valNeeded && prefix));
}
}
}