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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* 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
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*
* 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.
*
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package sun.tools.tree;
import sun.tools.java.*;
import sun.tools.asm.Assembler;
import sun.tools.asm.Label;
import java.io.PrintStream;
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 ConditionalExpression extends BinaryExpression {
Expression cond;
/**
* Constructor
*/
public ConditionalExpression(long where, Expression cond, Expression left, Expression right) {
super(COND, where, Type.tError, left, right);
this.cond = cond;
}
/**
* Order the expression based on precedence
*/
public Expression order() {
if (precedence() > cond.precedence()) {
UnaryExpression e = (UnaryExpression)cond;
cond = e.right;
e.right = order();
return e;
}
return this;
}
/**
* Check the expression
*/
public Vset checkValue(Environment env, Context ctx, Vset vset, Hashtable exp) {
ConditionVars cvars = cond.checkCondition(env, ctx, vset, exp);
vset = left.checkValue(env, ctx, cvars.vsTrue, exp).join(
right.checkValue(env, ctx, cvars.vsFalse, exp) );
cond = convert(env, ctx, Type.tBoolean, cond);
int tm = left.type.getTypeMask() | right.type.getTypeMask();
if ((tm & TM_ERROR) != 0) {
type = Type.tError;
return vset;
}
if (left.type.equals(right.type)) {
type = left.type;
} else if ((tm & TM_DOUBLE) != 0) {
type = Type.tDouble;
} else if ((tm & TM_FLOAT) != 0) {
type = Type.tFloat;
} else if ((tm & TM_LONG) != 0) {
type = Type.tLong;
} else if ((tm & TM_REFERENCE) != 0) {
try {
// This is wrong. We should be using their most common
// ancestor, instead.
type = env.implicitCast(right.type, left.type)
? left.type : right.type;
} catch (ClassNotFound e) {
type = Type.tError;
}
} else if (((tm & TM_CHAR) != 0) && left.fitsType(env, ctx, Type.tChar) && right.fitsType(env, ctx, Type.tChar)) {
type = Type.tChar;
} else if (((tm & TM_SHORT) != 0) && left.fitsType(env, ctx, Type.tShort) && right.fitsType(env, ctx, Type.tShort)) {
type = Type.tShort;
} else if (((tm & TM_BYTE) != 0) && left.fitsType(env, ctx, Type.tByte) && right.fitsType(env, ctx, Type.tByte)) {
type = Type.tByte;
} else {
type = Type.tInt;
}
left = convert(env, ctx, type, left);
right = convert(env, ctx, type, right);
return vset;
}
public Vset check(Environment env, Context ctx, Vset vset, Hashtable exp) {
vset = cond.checkValue(env, ctx, vset, exp);
cond = convert(env, ctx, Type.tBoolean, cond);
return left.check(env, ctx, vset.copy(), exp).join(right.check(env, ctx, vset, exp));
}
/**
* Check if constant
*/
public boolean isConstant() {
return cond.isConstant() && left.isConstant() && right.isConstant();
}
/**
* Simplify
*/
Expression simplify() {
if (cond.equals(true)) {
return left;
}
if (cond.equals(false)) {
return right;
}
return this;
}
/**
* Inline
*/
public Expression inline(Environment env, Context ctx) {
left = left.inline(env, ctx);
right = right.inline(env, ctx);
if ((left == null) && (right == null)) {
return cond.inline(env, ctx);
}
if (left == null) {
left = right;
right = null;
cond = new NotExpression(where, cond);
}
cond = cond.inlineValue(env, ctx);
return simplify();
}
public Expression inlineValue(Environment env, Context ctx) {
cond = cond.inlineValue(env, ctx);
left = left.inlineValue(env, ctx);
right = right.inlineValue(env, ctx);
return simplify();
}
/**
* The cost of inlining this expression
*/
public int costInline(int thresh, Environment env, Context ctx) {
// We need to check if right is null in case costInline()
// is called after this expression has been inlined.
// This call can happen, for example, in MemberDefinition#cleanup().
// (Fix for 4069861).
return 1 +
cond.costInline(thresh, env, ctx) +
left.costInline(thresh, env, ctx) +
((right == null) ? 0 : right.costInline(thresh, env, ctx));
}
/**
* Create a copy of the expression for method inlining
*/
public Expression copyInline(Context ctx) {
ConditionalExpression e = (ConditionalExpression)clone();
e.cond = cond.copyInline(ctx);
e.left = left.copyInline(ctx);
// If copyInline() is called after inlining is complete,
// right could be null.
e.right = (right == null) ? null : right.copyInline(ctx);
return e;
}
/**
* Code
*/
public void codeValue(Environment env, Context ctx, Assembler asm) {
Label l1 = new Label();
Label l2 = new Label();
cond.codeBranch(env, ctx, asm, l1, false);
left.codeValue(env, ctx, asm);
asm.add(where, opc_goto, l2);
asm.add(l1);
right.codeValue(env, ctx, asm);
asm.add(l2);
}
public void code(Environment env, Context ctx, Assembler asm) {
Label l1 = new Label();
cond.codeBranch(env, ctx, asm, l1, false);
left.code(env, ctx, asm);
if (right != null) {
Label l2 = new Label();
asm.add(where, opc_goto, l2);
asm.add(l1);
right.code(env, ctx, asm);
asm.add(l2);
} else {
asm.add(l1);
}
}
/**
* Print
*/
public void print(PrintStream out) {
out.print("(" + opNames[op] + " ");
cond.print(out);
out.print(" ");
left.print(out);
out.print(" ");
if (right != null) {
right.print(out);
} else {
out.print("<null>");
}
out.print(")");
}
}