Mercurial > jdk8-mips64-public > langtools / changeset

     1.1 --- a/src/share/classes/com/sun/tools/javac/jvm/Gen.java	Wed Jul 31 08:37:34 2013 -0700
     1.2 +++ b/src/share/classes/com/sun/tools/javac/jvm/Gen.java	Tue Aug 06 15:08:49 2013 +0100
     1.3 @@ -1478,74 +1478,82 @@
     1.4              code.statBegin(TreeInfo.endPos(body));
     1.5              genFinalizer(env);
     1.6              code.statBegin(TreeInfo.endPos(env.tree));
     1.7 -            Chain exitChain = code.branch(goto_);
     1.8 +            Chain exitChain;
     1.9 +            if (startpc != endpc) {
    1.10 +                exitChain = code.branch(goto_);
    1.11 +            } else {
    1.12 +                exitChain = code.branch(dontgoto);
    1.13 +            }
    1.14              endFinalizerGap(env);
    1.15 -            if (startpc != endpc) for (List<JCCatch> l = catchers; l.nonEmpty(); l = l.tail) {
    1.16 -                // start off with exception on stack
    1.17 -                code.entryPoint(stateTry, l.head.param.sym.type);
    1.18 -                genCatch(l.head, env, startpc, endpc, gaps);
    1.19 -                genFinalizer(env);
    1.20 -                if (hasFinalizer || l.tail.nonEmpty()) {
    1.21 -                    code.statBegin(TreeInfo.endPos(env.tree));
    1.22 -                    exitChain = Code.mergeChains(exitChain,
    1.23 -                                                 code.branch(goto_));
    1.24 +            if (startpc != endpc) {
    1.25 +                for (List<JCCatch> l = catchers; l.nonEmpty(); l = l.tail) {
    1.26 +                    // start off with exception on stack
    1.27 +                    code.entryPoint(stateTry, l.head.param.sym.type);
    1.28 +                    genCatch(l.head, env, startpc, endpc, gaps);
    1.29 +                    genFinalizer(env);
    1.30 +                    if (hasFinalizer || l.tail.nonEmpty()) {
    1.31 +                        code.statBegin(TreeInfo.endPos(env.tree));
    1.32 +                        exitChain = Code.mergeChains(exitChain,
    1.33 +                                                     code.branch(goto_));
    1.34 +                    }
    1.35 +                    endFinalizerGap(env);
    1.36                  }
    1.37 -                endFinalizerGap(env);
    1.38 -            }
    1.39 -            if (hasFinalizer) {
    1.40 -                // Create a new register segement to avoid allocating
    1.41 -                // the same variables in finalizers and other statements.
    1.42 -                code.newRegSegment();
    1.43  
    1.44 -                // Add a catch-all clause.
    1.45 +                if (hasFinalizer) {
    1.46 +                    // Create a new register segement to avoid allocating
    1.47 +                    // the same variables in finalizers and other statements.
    1.48 +                    code.newRegSegment();
    1.49  
    1.50 -                // start off with exception on stack
    1.51 -                int catchallpc = code.entryPoint(stateTry, syms.throwableType);
    1.52 +                    // Add a catch-all clause.
    1.53  
    1.54 -                // Register all exception ranges for catch all clause.
    1.55 -                // The range of the catch all clause is from the beginning
    1.56 -                // of the try or synchronized block until the present
    1.57 -                // code pointer excluding all gaps in the current
    1.58 -                // environment's GenContext.
    1.59 -                int startseg = startpc;
    1.60 -                while (env.info.gaps.nonEmpty()) {
    1.61 -                    int endseg = env.info.gaps.next().intValue();
    1.62 -                    registerCatch(body.pos(), startseg, endseg,
    1.63 -                                  catchallpc, 0);
    1.64 -                    startseg = env.info.gaps.next().intValue();
    1.65 -                }
    1.66 -                code.statBegin(TreeInfo.finalizerPos(env.tree));
    1.67 -                code.markStatBegin();
    1.68 +                    // start off with exception on stack
    1.69 +                    int catchallpc = code.entryPoint(stateTry, syms.throwableType);
    1.70  
    1.71 -                Item excVar = makeTemp(syms.throwableType);
    1.72 -                excVar.store();
    1.73 -                genFinalizer(env);
    1.74 -                excVar.load();
    1.75 -                registerCatch(body.pos(), startseg,
    1.76 -                              env.info.gaps.next().intValue(),
    1.77 -                              catchallpc, 0);
    1.78 -                code.emitop0(athrow);
    1.79 -                code.markDead();
    1.80 -
    1.81 -                // If there are jsr's to this finalizer, ...
    1.82 -                if (env.info.cont != null) {
    1.83 -                    // Resolve all jsr's.
    1.84 -                    code.resolve(env.info.cont);
    1.85 -
    1.86 -                    // Mark statement line number
    1.87 +                    // Register all exception ranges for catch all clause.
    1.88 +                    // The range of the catch all clause is from the beginning
    1.89 +                    // of the try or synchronized block until the present
    1.90 +                    // code pointer excluding all gaps in the current
    1.91 +                    // environment's GenContext.
    1.92 +                    int startseg = startpc;
    1.93 +                    while (env.info.gaps.nonEmpty()) {
    1.94 +                        int endseg = env.info.gaps.next().intValue();
    1.95 +                        registerCatch(body.pos(), startseg, endseg,
    1.96 +                                      catchallpc, 0);
    1.97 +                        startseg = env.info.gaps.next().intValue();
    1.98 +                    }
    1.99                      code.statBegin(TreeInfo.finalizerPos(env.tree));
   1.100                      code.markStatBegin();
   1.101  
   1.102 -                    // Save return address.
   1.103 -                    LocalItem retVar = makeTemp(syms.throwableType);
   1.104 -                    retVar.store();
   1.105 +                    Item excVar = makeTemp(syms.throwableType);
   1.106 +                    excVar.store();
   1.107 +                    genFinalizer(env);
   1.108 +                    excVar.load();
   1.109 +                    registerCatch(body.pos(), startseg,
   1.110 +                                  env.info.gaps.next().intValue(),
   1.111 +                                  catchallpc, 0);
   1.112 +                    code.emitop0(athrow);
   1.113 +                    code.markDead();
   1.114  
   1.115 -                    // Generate finalizer code.
   1.116 -                    env.info.finalize.genLast();
   1.117 +                    // If there are jsr's to this finalizer, ...
   1.118 +                    if (env.info.cont != null) {
   1.119 +                        // Resolve all jsr's.
   1.120 +                        code.resolve(env.info.cont);
   1.121  
   1.122 -                    // Return.
   1.123 -                    code.emitop1w(ret, retVar.reg);
   1.124 -                    code.markDead();
   1.125 +                        // Mark statement line number
   1.126 +                        code.statBegin(TreeInfo.finalizerPos(env.tree));
   1.127 +                        code.markStatBegin();
   1.128 +
   1.129 +                        // Save return address.
   1.130 +                        LocalItem retVar = makeTemp(syms.throwableType);
   1.131 +                        retVar.store();
   1.132 +
   1.133 +                        // Generate finalizer code.
   1.134 +                        env.info.finalize.genLast();
   1.135 +
   1.136 +                        // Return.
   1.137 +                        code.emitop1w(ret, retVar.reg);
   1.138 +                        code.markDead();
   1.139 +                    }
   1.140                  }
   1.141              }
   1.142              // Resolve all breaks.

     2.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     2.2 +++ b/test/tools/javac/T8022186/DeadCodeGeneratedForEmptyTryTest.java	Tue Aug 06 15:08:49 2013 +0100
     2.3 @@ -0,0 +1,166 @@
     2.4 +/*
     2.5 + * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
     2.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     2.7 + *
     2.8 + * This code is free software; you can redistribute it and/or modify it
     2.9 + * under the terms of the GNU General Public License version 2 only, as
    2.10 + * published by the Free Software Foundation.  Oracle designates this
    2.11 + * particular file as subject to the "Classpath" exception as provided
    2.12 + * by Oracle in the LICENSE file that accompanied this code.
    2.13 + *
    2.14 + * This code is distributed in the hope that it will be useful, but WITHOUT
    2.15 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    2.16 + * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    2.17 + * version 2 for more details (a copy is included in the LICENSE file that
    2.18 + * accompanied this code).
    2.19 + *
    2.20 + * You should have received a copy of the GNU General Public License version
    2.21 + * 2 along with this work; if not, write to the Free Software Foundation,
    2.22 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
    2.23 + *
    2.24 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
    2.25 + * or visit www.oracle.com if you need additional information or have any
    2.26 + * questions.
    2.27 + */
    2.28 +
    2.29 +/*
    2.30 + * @test
    2.31 + * @bug 8022186
    2.32 + * @summary javac generates dead code if a try with an empty body has a finalizer
    2.33 + */
    2.34 +
    2.35 +import com.sun.tools.classfile.Attribute;
    2.36 +import com.sun.tools.classfile.ClassFile;
    2.37 +import com.sun.tools.classfile.Code_attribute;
    2.38 +import com.sun.tools.classfile.ConstantPool;
    2.39 +import com.sun.tools.classfile.ConstantPool.CONSTANT_String_info;
    2.40 +import com.sun.tools.classfile.ConstantPool.CPInfo;
    2.41 +import com.sun.tools.classfile.ConstantPool.InvalidIndex;
    2.42 +import com.sun.tools.classfile.Instruction;
    2.43 +import com.sun.tools.classfile.Instruction.KindVisitor;
    2.44 +import com.sun.tools.classfile.Instruction.TypeKind;
    2.45 +import com.sun.tools.classfile.Method;
    2.46 +import com.sun.tools.javac.util.Assert;
    2.47 +import java.io.BufferedInputStream;
    2.48 +import java.nio.file.Files;
    2.49 +import java.nio.file.Path;
    2.50 +import java.nio.file.Paths;
    2.51 +
    2.52 +public class DeadCodeGeneratedForEmptyTryTest {
    2.53 +
    2.54 +    public static void main(String[] args) throws Exception {
    2.55 +        new DeadCodeGeneratedForEmptyTryTest().run();
    2.56 +    }
    2.57 +
    2.58 +    void run() throws Exception {
    2.59 +        checkClassFile(Paths.get(System.getProperty("test.classes"),
    2.60 +                this.getClass().getName() + "$Test.class"));
    2.61 +    }
    2.62 +
    2.63 +    int utf8Index;
    2.64 +    int numberOfRefToStr = 0;
    2.65 +    ConstantPool constantPool;
    2.66 +
    2.67 +    void checkClassFile(final Path path) throws Exception {
    2.68 +        ClassFile classFile = ClassFile.read(
    2.69 +                new BufferedInputStream(Files.newInputStream(path)));
    2.70 +        constantPool = classFile.constant_pool;
    2.71 +        utf8Index = constantPool.getUTF8Index("STR_TO_LOOK_FOR");
    2.72 +        for (Method method: classFile.methods) {
    2.73 +            if (method.getName(constantPool).equals("methodToLookFor")) {
    2.74 +                Code_attribute codeAtt = (Code_attribute)method.attributes.get(Attribute.Code);
    2.75 +                for (Instruction inst: codeAtt.getInstructions()) {
    2.76 +                    inst.accept(codeVisitor, null);
    2.77 +                }
    2.78 +            }
    2.79 +        }
    2.80 +        Assert.check(numberOfRefToStr == 1,
    2.81 +                "There should only be one reference to a CONSTANT_String_info structure in the generated code");
    2.82 +    }
    2.83 +
    2.84 +    CodeVisitor codeVisitor = new CodeVisitor();
    2.85 +
    2.86 +    class CodeVisitor implements KindVisitor<Void, Void> {
    2.87 +
    2.88 +        void checkIndirectRefToString(int cp_index) {
    2.89 +            try {
    2.90 +                CPInfo cInfo = constantPool.get(cp_index);
    2.91 +                if (cInfo instanceof CONSTANT_String_info) {
    2.92 +                    CONSTANT_String_info strInfo = (CONSTANT_String_info)cInfo;
    2.93 +                    if (strInfo.string_index == utf8Index) {
    2.94 +                        numberOfRefToStr++;
    2.95 +                    }
    2.96 +                }
    2.97 +            } catch (InvalidIndex ex) {
    2.98 +                throw new AssertionError("invalid constant pool index at " + cp_index);
    2.99 +            }
   2.100 +        }
   2.101 +
   2.102 +        @Override
   2.103 +        public Void visitNoOperands(Instruction instr, Void p) {
   2.104 +            return null;
   2.105 +        }
   2.106 +
   2.107 +        @Override
   2.108 +        public Void visitArrayType(Instruction instr, TypeKind kind, Void p) {
   2.109 +            return null;
   2.110 +        }
   2.111 +
   2.112 +        @Override
   2.113 +        public Void visitBranch(Instruction instr, int offset, Void p) {
   2.114 +            return null;
   2.115 +        }
   2.116 +
   2.117 +        @Override
   2.118 +        public Void visitConstantPoolRef(Instruction instr, int index, Void p) {
   2.119 +            checkIndirectRefToString(index);
   2.120 +            return null;
   2.121 +        }
   2.122 +
   2.123 +        @Override
   2.124 +        public Void visitConstantPoolRefAndValue(Instruction instr, int index, int value, Void p) {
   2.125 +            checkIndirectRefToString(index);
   2.126 +            return null;
   2.127 +        }
   2.128 +
   2.129 +        @Override
   2.130 +        public Void visitLocal(Instruction instr, int index, Void p) {
   2.131 +            return null;
   2.132 +        }
   2.133 +
   2.134 +        @Override
   2.135 +        public Void visitLocalAndValue(Instruction instr, int index, int value, Void p) {
   2.136 +            return null;
   2.137 +        }
   2.138 +
   2.139 +        @Override
   2.140 +        public Void visitLookupSwitch(Instruction instr, int default_, int npairs, int[] matches, int[] offsets, Void p) {
   2.141 +            return null;
   2.142 +        }
   2.143 +
   2.144 +        @Override
   2.145 +        public Void visitTableSwitch(Instruction instr, int default_, int low, int high, int[] offsets, Void p) {
   2.146 +            return null;
   2.147 +        }
   2.148 +
   2.149 +        @Override
   2.150 +        public Void visitValue(Instruction instr, int value, Void p) {
   2.151 +            return null;
   2.152 +        }
   2.153 +
   2.154 +        @Override
   2.155 +        public Void visitUnknown(Instruction instr, Void p) {
   2.156 +            return null;
   2.157 +        }
   2.158 +
   2.159 +    }
   2.160 +
   2.161 +    public class Test {
   2.162 +        void methodToLookFor() {
   2.163 +            try {
   2.164 +            } finally {
   2.165 +                System.out.println("STR_TO_LOOK_FOR");
   2.166 +            }
   2.167 +        }
   2.168 +    }
   2.169 +}