1/* 2 * Copyright (c) 1994, 2003, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26package sun.tools.tree; 27 28import sun.tools.java.*; 29import sun.tools.asm.Assembler; 30import sun.tools.asm.Label; 31import java.io.PrintStream; 32import java.util.Hashtable; 33 34/** 35 * WARNING: The contents of this source file are not part of any 36 * supported API. Code that depends on them does so at its own risk: 37 * they are subject to change or removal without notice. 38 */ 39public 40class ForStatement extends Statement { 41 Statement init; 42 Expression cond; 43 Expression inc; 44 Statement body; 45 46 /** 47 * Constructor 48 */ 49 public ForStatement(long where, Statement init, Expression cond, Expression inc, Statement body) { 50 super(FOR, where); 51 this.init = init; 52 this.cond = cond; 53 this.inc = inc; 54 this.body = body; 55 } 56 57 /** 58 * Check statement 59 */ 60 Vset check(Environment env, Context ctx, Vset vset, Hashtable<Object, Object> exp) { 61 checkLabel(env, ctx); 62 vset = reach(env, vset); 63 Context initctx = new Context(ctx, this); 64 if (init != null) { 65 vset = init.checkBlockStatement(env, initctx, vset, exp); 66 } 67 CheckContext newctx = new CheckContext(initctx, this); 68 // remember what was unassigned on entry 69 Vset vsEntry = vset.copy(); 70 ConditionVars cvars; 71 if (cond != null) { 72 cvars = cond.checkCondition(env, newctx, vset, exp); 73 cond = convert(env, newctx, Type.tBoolean, cond); 74 } else { 75 // a missing test is equivalent to "true" 76 cvars = new ConditionVars(); 77 cvars.vsFalse = Vset.DEAD_END; 78 cvars.vsTrue = vset; 79 } 80 vset = body.check(env, newctx, cvars.vsTrue, exp); 81 vset = vset.join(newctx.vsContinue); 82 if (inc != null) { 83 vset = inc.check(env, newctx, vset, exp); 84 } 85 // Make sure the back-branch fits the entry of the loop. 86 // Must include variables declared in the for-init part in the 87 // set of variables visible upon loop entry that must be checked. 88 initctx.checkBackBranch(env, this, vsEntry, vset); 89 // exit by testing false or executing a break; 90 vset = newctx.vsBreak.join(cvars.vsFalse); 91 return ctx.removeAdditionalVars(vset); 92 } 93 94 /** 95 * Inline 96 */ 97 public Statement inline(Environment env, Context ctx) { 98 ctx = new Context(ctx, this); 99 if (init != null) { 100 Statement body[] = {init, this}; 101 init = null; 102 return new CompoundStatement(where, body).inline(env, ctx); 103 } 104 if (cond != null) { 105 cond = cond.inlineValue(env, ctx); 106 } 107 if (body != null) { 108 body = body.inline(env, ctx); 109 } 110 if (inc != null) { 111 inc = inc.inline(env, ctx); 112 } 113 return this; 114 } 115 116 /** 117 * Create a copy of the statement for method inlining 118 */ 119 public Statement copyInline(Context ctx, boolean valNeeded) { 120 ForStatement s = (ForStatement)clone(); 121 if (init != null) { 122 s.init = init.copyInline(ctx, valNeeded); 123 } 124 if (cond != null) { 125 s.cond = cond.copyInline(ctx); 126 } 127 if (body != null) { 128 s.body = body.copyInline(ctx, valNeeded); 129 } 130 if (inc != null) { 131 s.inc = inc.copyInline(ctx); 132 } 133 return s; 134 } 135 136 /** 137 * The cost of inlining this statement 138 */ 139 public int costInline(int thresh, Environment env, Context ctx) { 140 int cost = 2; 141 if (init != null) { 142 cost += init.costInline(thresh, env, ctx); 143 } 144 if (cond != null) { 145 cost += cond.costInline(thresh, env, ctx); 146 } 147 if (body != null) { 148 cost += body.costInline(thresh, env, ctx); 149 } 150 if (inc != null) { 151 cost += inc.costInline(thresh, env, ctx); 152 } 153 return cost; 154 } 155 156 /** 157 * Code 158 */ 159 public void code(Environment env, Context ctx, Assembler asm) { 160 CodeContext newctx = new CodeContext(ctx, this); 161 if (init != null) { 162 init.code(env, newctx, asm); 163 } 164 165 Label l1 = new Label(); 166 Label l2 = new Label(); 167 168 asm.add(where, opc_goto, l2); 169 170 asm.add(l1); 171 if (body != null) { 172 body.code(env, newctx, asm); 173 } 174 175 asm.add(newctx.contLabel); 176 if (inc != null) { 177 inc.code(env, newctx, asm); 178 } 179 180 asm.add(l2); 181 if (cond != null) { 182 cond.codeBranch(env, newctx, asm, l1, true); 183 } else { 184 asm.add(where, opc_goto, l1); 185 } 186 asm.add(newctx.breakLabel); 187 } 188 189 /** 190 * Print 191 */ 192 public void print(PrintStream out, int indent) { 193 super.print(out, indent); 194 out.print("for ("); 195 if (init != null) { 196 init.print(out, indent); 197 out.print(" "); 198 } else { 199 out.print("; "); 200 } 201 if (cond != null) { 202 cond.print(out); 203 out.print(" "); 204 } 205 out.print("; "); 206 if (inc != null) { 207 inc.print(out); 208 } 209 out.print(") "); 210 if (body != null) { 211 body.print(out, indent); 212 } else { 213 out.print(";"); 214 } 215 } 216} 217