7093325: Redundant entry in bytecode exception table
authormcimadamore
Mon, 17 Oct 2011 12:57:36 +0100
changeset 10811 4d4ed480210e
parent 10810 9444a714fdaf
child 10812 7341374e12e8
7093325: Redundant entry in bytecode exception table Summary: Inlining of finalizers does not update gaps list accordingly Reviewed-by: jjg
langtools/src/share/classes/com/sun/tools/javac/jvm/Code.java
langtools/src/share/classes/com/sun/tools/javac/jvm/Gen.java
langtools/test/tools/javac/T7093325.java
--- a/langtools/src/share/classes/com/sun/tools/javac/jvm/Code.java	Mon Oct 17 12:54:33 2011 +0100
+++ b/langtools/src/share/classes/com/sun/tools/javac/jvm/Code.java	Mon Oct 17 12:57:36 2011 +0100
@@ -1542,7 +1542,28 @@
      */
     public void addCatch(
         char startPc, char endPc, char handlerPc, char catchType) {
-        catchInfo.append(new char[]{startPc, endPc, handlerPc, catchType});
+            catchInfo.append(new char[]{startPc, endPc, handlerPc, catchType});
+        }
+
+
+    public void compressCatchTable() {
+        ListBuffer<char[]> compressedCatchInfo = ListBuffer.lb();
+        List<Integer> handlerPcs = List.nil();
+        for (char[] catchEntry : catchInfo.elems) {
+            handlerPcs = handlerPcs.prepend((int)catchEntry[2]);
+        }
+        for (char[] catchEntry : catchInfo.elems) {
+            int startpc = catchEntry[0];
+            int endpc = catchEntry[1];
+            if (startpc == endpc ||
+                    (startpc == (endpc - 1) &&
+                    handlerPcs.contains(startpc))) {
+                continue;
+            } else {
+                compressedCatchInfo.append(catchEntry);
+            }
+        }
+        catchInfo = compressedCatchInfo;
     }
 
 
--- a/langtools/src/share/classes/com/sun/tools/javac/jvm/Gen.java	Mon Oct 17 12:54:33 2011 +0100
+++ b/langtools/src/share/classes/com/sun/tools/javac/jvm/Gen.java	Mon Oct 17 12:57:36 2011 +0100
@@ -959,6 +959,9 @@
                     code.lastFrame = null;
                     code.frameBeforeLast = null;
                 }
+
+                //compress exception table
+                code.compressCatchTable();
             }
         }
 
@@ -1437,7 +1440,6 @@
                     code.markDead();
                 }
             }
-
             // Resolve all breaks.
             code.resolve(exitChain);
 
@@ -1496,23 +1498,21 @@
         void registerCatch(DiagnosticPosition pos,
                            int startpc, int endpc,
                            int handler_pc, int catch_type) {
-            if (startpc != endpc) {
-                char startpc1 = (char)startpc;
-                char endpc1 = (char)endpc;
-                char handler_pc1 = (char)handler_pc;
-                if (startpc1 == startpc &&
-                    endpc1 == endpc &&
-                    handler_pc1 == handler_pc) {
-                    code.addCatch(startpc1, endpc1, handler_pc1,
-                                  (char)catch_type);
+            char startpc1 = (char)startpc;
+            char endpc1 = (char)endpc;
+            char handler_pc1 = (char)handler_pc;
+            if (startpc1 == startpc &&
+                endpc1 == endpc &&
+                handler_pc1 == handler_pc) {
+                code.addCatch(startpc1, endpc1, handler_pc1,
+                              (char)catch_type);
+            } else {
+                if (!useJsrLocally && !target.generateStackMapTable()) {
+                    useJsrLocally = true;
+                    throw new CodeSizeOverflow();
                 } else {
-                    if (!useJsrLocally && !target.generateStackMapTable()) {
-                        useJsrLocally = true;
-                        throw new CodeSizeOverflow();
-                    } else {
-                        log.error(pos, "limit.code.too.large.for.try.stmt");
-                        nerrs++;
-                    }
+                    log.error(pos, "limit.code.too.large.for.try.stmt");
+                    nerrs++;
                 }
             }
         }
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/langtools/test/tools/javac/T7093325.java	Mon Oct 17 12:57:36 2011 +0100
@@ -0,0 +1,262 @@
+/*
+ * Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
+ * 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.
+ *
+ * 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
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 7093325
+ * @summary Redundant entry in bytecode exception table
+ */
+
+import com.sun.source.util.JavacTask;
+import com.sun.tools.classfile.Attribute;
+import com.sun.tools.classfile.ClassFile;
+import com.sun.tools.classfile.Code_attribute;
+import com.sun.tools.classfile.ConstantPool.*;
+import com.sun.tools.classfile.Method;
+import com.sun.tools.javac.api.JavacTool;
+
+import java.io.File;
+import java.net.URI;
+import java.util.Arrays;
+import javax.tools.JavaCompiler;
+import javax.tools.JavaFileObject;
+import javax.tools.SimpleJavaFileObject;
+import javax.tools.StandardJavaFileManager;
+import javax.tools.ToolProvider;
+
+
+public class T7093325 {
+
+    /** global decls ***/
+
+    // Create a single file manager and reuse it for each compile to save time.
+    static StandardJavaFileManager fm = JavacTool.create().getStandardFileManager(null, null, null);
+
+    //statistics
+    static int checkCount = 0;
+
+    enum StatementKind {
+        THROW("throw new RuntimeException();", false, false),
+        RETURN_NONEMPTY("System.out.println(); return;", true, false),
+        RETURN_EMPTY("return;", true, true),
+        APPLY("System.out.println();", true, false);
+
+        String stmt;
+        boolean canInline;
+        boolean empty;
+
+        private StatementKind(String stmt, boolean canInline, boolean empty) {
+            this.stmt = stmt;
+            this.canInline = canInline;
+            this.empty = empty;
+        }
+    }
+
+    enum CatchArity {
+        NONE(""),
+        ONE("catch (A a) { #S1 }"),
+        TWO("catch (B b) { #S2 }"),
+        THREE("catch (C c) { #S3 }"),
+        FOUR("catch (D d) { #S4 }");
+
+        String catchStr;
+
+        private CatchArity(String catchStr) {
+            this.catchStr = catchStr;
+        }
+
+        String catchers() {
+            if (this.ordinal() == 0) {
+                return catchStr;
+            } else {
+                return CatchArity.values()[this.ordinal() - 1].catchers() + catchStr;
+            }
+        }
+    }
+
+    public static void main(String... args) throws Exception {
+        for (CatchArity ca : CatchArity.values()) {
+            for (StatementKind stmt0 : StatementKind.values()) {
+                if (ca.ordinal() == 0) {
+                    new T7093325(ca, stmt0).compileAndCheck();
+                    continue;
+                }
+                for (StatementKind stmt1 : StatementKind.values()) {
+                    if (ca.ordinal() == 1) {
+                        new T7093325(ca, stmt0, stmt1).compileAndCheck();
+                        continue;
+                    }
+                    for (StatementKind stmt2 : StatementKind.values()) {
+                        if (ca.ordinal() == 2) {
+                            new T7093325(ca, stmt0, stmt1, stmt2).compileAndCheck();
+                            continue;
+                        }
+                        for (StatementKind stmt3 : StatementKind.values()) {
+                            if (ca.ordinal() == 3) {
+                                new T7093325(ca, stmt0, stmt1, stmt2, stmt3).compileAndCheck();
+                                continue;
+                            }
+                            for (StatementKind stmt4 : StatementKind.values()) {
+                                if (ca.ordinal() == 4) {
+                                    new T7093325(ca, stmt0, stmt1, stmt2, stmt3, stmt4).compileAndCheck();
+                                    continue;
+                                }
+                                for (StatementKind stmt5 : StatementKind.values()) {
+                                    new T7093325(ca, stmt0, stmt1, stmt2, stmt3, stmt4, stmt5).compileAndCheck();
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        }
+
+        System.out.println("Total checks made: " + checkCount);
+    }
+
+    /** instance decls **/
+
+    CatchArity ca;
+    StatementKind[] stmts;
+
+    public T7093325(CatchArity ca, StatementKind... stmts) {
+        this.ca = ca;
+        this.stmts = stmts;
+    }
+
+    void compileAndCheck() throws Exception {
+        final JavaCompiler tool = ToolProvider.getSystemJavaCompiler();
+        JavaSource source = new JavaSource();
+        JavacTask ct = (JavacTask)tool.getTask(null, fm, null,
+                null, null, Arrays.asList(source));
+        ct.call();
+        verifyBytecode(source);
+    }
+
+    void verifyBytecode(JavaSource source) {
+        checkCount++;
+        boolean lastInlined = false;
+        boolean hasCode = false;
+        int gapsCount = 0;
+        for (int i = 0; i < stmts.length ; i++) {
+            lastInlined = stmts[i].canInline;
+            hasCode = hasCode || !stmts[i].empty;
+            if (lastInlined && hasCode) {
+                hasCode = false;
+                gapsCount++;
+            }
+        }
+        if (!lastInlined) {
+            gapsCount++;
+        }
+
+        //System.out.printf("gaps %d \n %s \n", gapsCount, source.toString());
+
+        File compiledTest = new File("Test.class");
+        try {
+            ClassFile cf = ClassFile.read(compiledTest);
+            if (cf == null) {
+                throw new Error("Classfile not found: " + compiledTest.getName());
+            }
+
+            Method test_method = null;
+            for (Method m : cf.methods) {
+                if (m.getName(cf.constant_pool).equals("test")) {
+                    test_method = m;
+                    break;
+                }
+            }
+
+            if (test_method == null) {
+                throw new Error("Method test() not found in class Test");
+            }
+
+            Code_attribute code = null;
+            for (Attribute a : test_method.attributes) {
+                if (a.getName(cf.constant_pool).equals(Attribute.Code)) {
+                    code = (Code_attribute)a;
+                    break;
+                }
+            }
+
+            if (code == null) {
+                throw new Error("Code attribute not found in method test()");
+            }
+
+            int actualGapsCount = 0;
+            for (int i = 0; i < code.exception_table_langth ; i++) {
+                int catchType = code.exception_table[i].catch_type;
+                if (catchType == 0) { //any
+                    actualGapsCount++;
+                }
+            }
+
+            if (actualGapsCount != gapsCount) {
+                throw new Error("Bad exception table for test()\n" +
+                            "expected gaps: " + gapsCount + "\n" +
+                            "found gaps: " + actualGapsCount + "\n" +
+                            source);
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+            throw new Error("error reading " + compiledTest +": " + e);
+        }
+
+    }
+
+    class JavaSource extends SimpleJavaFileObject {
+
+        static final String source_template =
+                "class A extends RuntimeException {} \n" +
+                "class B extends RuntimeException {} \n" +
+                "class C extends RuntimeException {} \n" +
+                "class D extends RuntimeException {} \n" +
+                "class E extends RuntimeException {} \n" +
+                "class Test {\n" +
+                "   void test() {\n" +
+                "   try { #S0 } #C finally { System.out.println(); }\n" +
+                "   }\n" +
+                "}";
+
+        String source;
+
+        public JavaSource() {
+            super(URI.create("myfo:/Test.java"), JavaFileObject.Kind.SOURCE);
+            source = source_template.replace("#C", ca.catchers());
+            source = source.replace("#S0", stmts[0].stmt);
+            for (int i = 1; i < ca.ordinal() + 1; i++) {
+                source = source.replace("#S" + i, stmts[i].stmt);
+            }
+        }
+
+        @Override
+        public String toString() {
+            return source;
+        }
+
+        @Override
+        public CharSequence getCharContent(boolean ignoreEncodingErrors) {
+            return source;
+        }
+    }
+}