// ASM: a very sm14all and fast Java bytecode manipulation framework // Copyright (c) 2000-2011 INRIA, France Telecom // All rights reserved. // // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions // are met: // 1. Redistributions of source code must retain the above copyright // notice, this list of conditions and the following disclaimer. // 2. Redistributions in binary form must reproduce the above copyright // notice, this list of conditions and the following disclaimer in the // documentation and/or other materials provided with the distribution. // 3. Neither the name of the copyright holders nor the names of its // contributors may be used to endorse or promote products derived from // this software without specific prior written permission. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF // THE POSSIBILITY OF SUCH DAMAGE. package org.objectweb.asm.commons; import static org.junit.jupiter.api.Assertions.assertDoesNotThrow; import static org.junit.jupiter.api.Assertions.assertEquals; import static org.junit.jupiter.api.Assertions.assertThrows; import static org.objectweb.asm.commons.MethodNodeBuilder.buildClassWithMethod; import static org.objectweb.asm.commons.MethodNodeBuilder.toText; import org.junit.jupiter.api.Test; import org.junit.jupiter.params.ParameterizedTest; import org.junit.jupiter.params.provider.MethodSource; import org.junit.jupiter.params.provider.ValueSource; import org.objectweb.asm.ClassReader; import org.objectweb.asm.ClassVisitor; import org.objectweb.asm.ClassWriter; import org.objectweb.asm.Label; import org.objectweb.asm.MethodVisitor; import org.objectweb.asm.Opcodes; import org.objectweb.asm.test.AsmTest; import org.objectweb.asm.test.ClassFile; import org.objectweb.asm.tree.MethodNode; /** * Unit tests for {@link JSRInlinerAdapter}. * * @author Eric Bruneton */ class JsrInlinerAdapterTest extends AsmTest { // Some local variable numbers used in tests. private static final int LOCAL1 = 1; private static final int LOCAL2 = 2; private static final int LOCAL3 = 3; private static final int LOCAL4 = 4; private static final int LOCAL5 = 5; // Labels used to generate test cases. private final Label label0 = new Label(); private final Label label1 = new Label(); private final Label label2 = new Label(); private final Label label3 = new Label(); private final Label label4 = new Label(); private final Label label5 = new Label(); private final Label label6 = new Label(); private final Label label7 = new Label(); private final Label label8 = new Label(); private final Label label9 = new Label(); private final Label label10 = new Label(); private final Label label11 = new Label(); private final Label label12 = new Label(); // Labels used to generate expected results. private final Label expectedLabel0 = new Label(); private final Label expectedLabel1 = new Label(); private final Label expectedLabel2 = new Label(); private final Label expectedLabel3 = new Label(); private final Label expectedLabel4 = new Label(); private final Label expectedLabel5 = new Label(); private final Label expectedLabel6 = new Label(); private final Label expectedLabel7 = new Label(); private final Label expectedLabel8 = new Label(); private final Label expectedLabel9 = new Label(); private final Label expectedLabel10 = new Label(); private final Label expectedLabel11 = new Label(); private final Label expectedLabel12 = new Label(); private final Label expectedLabel13 = new Label(); private final Label expectedLabel14 = new Label(); private final Label expectedLabel15 = new Label(); private final Label expectedLabel16 = new Label(); private final Label expectedLabel17 = new Label(); private final Label expectedLabel18 = new Label(); private final Label expectedLabel19 = new Label(); private final Label expectedLabel20 = new Label(); private final Label expectedLabel21 = new Label(); private final Label expectedLabel22 = new Label(); private final Label expectedLabel23 = new Label(); private final Label expectedLabel24 = new Label(); private final Label expectedLabel25 = new Label(); private final Label expectedLabel26 = new Label(); private final Label expectedLabel27 = new Label(); private final Label expectedLabel28 = new Label(); @Test void testConstructor() { new JSRInlinerAdapter(null, Opcodes.ACC_PUBLIC, "name", "()V", null, null); assertThrows( IllegalStateException.class, () -> new JSRInlinerAdapter(null, Opcodes.ACC_PUBLIC, "name", "()V", null, null) {}); } /** * Tests a method which has the most basic try{}finally form imaginable. More * specifically: * * 
   * public void a() {
   *   int a = 0;
   *   try {
   *     a++;
   *   } finally {
   *     a--;
   *   }
   * }
   *
*/ @Test void testInlineJsr_basicTryFinally() { MethodNode inputMethod = new MethodNodeBuilder(1, 4) .iconst_0() .istore(1) .label(label0) // Body of try block. .iinc(1, 1) .go(label3) .label(label1) // Exception handler. .astore(3) .jsr(label2) .aload(3) .athrow() .label(label2) // Subroutine. .astore(2) .iinc(1, -1) .ret(2) .label(label3) // Non-exceptional exit from try block. .jsr(label2) .label(label4) .vreturn() .trycatch(label0, label1, label1) .trycatch(label3, label4, label1) .build(); MethodNode inlinedMethod = new MethodNode(Opcodes.ACC_PUBLIC, "m", "()V", null, null); inputMethod.accept( new JSRInlinerAdapter(inlinedMethod, Opcodes.ACC_PUBLIC, "m", "()V", null, null)); MethodNode expectedMethod = new MethodNodeBuilder(1, 4) .iconst_0() .istore(1) .label(expectedLabel0) // Try/catch block. .iinc(1, 1) .go(expectedLabel3) .label(expectedLabel1) // Exception handler. .astore(3) .aconst_null() .go(expectedLabel6) .label(expectedLabel2) .aload(3) .athrow() .label(expectedLabel3) // On non-exceptional exit, try block leads here. .aconst_null() .go(expectedLabel7) .label(expectedLabel4) .label(expectedLabel5) .vreturn() .label(expectedLabel6) // First instantiation of subroutine. .astore(2) .iinc(1, -1) .go(expectedLabel2) .label() .label(expectedLabel7) // Second instantiation of subroutine. .astore(2) .iinc(1, -1) .go(expectedLabel4) .label() .trycatch(expectedLabel0, expectedLabel1, expectedLabel1) .trycatch(expectedLabel3, expectedLabel5, expectedLabel1) .build(); assertEquals(toText(expectedMethod), toText(inlinedMethod)); assertDoesNotThrow(() -> MethodNodeBuilder.buildClassWithMethod(inlinedMethod).newInstance()); } /** * Tests a method which has an if/else in the finally clause. More specifically: * * 
   * public void a() {
   *   int a = 0;
   *   try {
   *     a++;
   *   } finally {
   *     if (a == 0) {
   *       a += 2;
   *     } else {
   *       a += 3;
   *     }
   *   }
   * }
   *
*/ @Test void testInlineJsr_ifElseInFinally() { MethodNode inputMethod = new MethodNodeBuilder(1, 4) .iconst_0() .istore(1) .label(label0) // Body of try block. .iinc(1, 1) .go(label5) .label(label1) // Exception handler. .astore(3) .jsr(label2) .aload(3) .athrow() .label(label2) // Subroutine. .astore(2) .iload(1) .ifne(label3) .iinc(1, 2) .go(label4) .label(label3) // Test "a != 0". .iinc(1, 3) .label(label4) // Common exit. .ret(2) .label(label5) // Non-exceptional exit from try block. .jsr(label2) .label(label6) // Used in the TRYCATCH below. .vreturn() .trycatch(label0, label1, label1) .trycatch(label5, label6, label1) .build(); MethodNode inlinedMethod = new MethodNode(Opcodes.ACC_PUBLIC, "m", "()V", null, null); inputMethod.accept( new JSRInlinerAdapter(inlinedMethod, Opcodes.ACC_PUBLIC, "m", "()V", null, null)); MethodNode expectedMethod = new MethodNodeBuilder(1, 4) .iconst_0() .istore(1) .label(expectedLabel0) // Try/catch block. .iinc(1, 1) .go(expectedLabel3) .label(expectedLabel1) // Exception handler. .astore(3) .aconst_null() .go(expectedLabel6) .label(expectedLabel2) .aload(3) .athrow() .label(expectedLabel3) // On non-exceptional exit, try block leads here. .aconst_null() .go(expectedLabel9) .label(expectedLabel4) .label(expectedLabel5) .vreturn() .label(expectedLabel6) // First instantiation of subroutine. .astore(2) .iload(1) .ifne(expectedLabel7) .iinc(1, 2) .go(expectedLabel8) .label(expectedLabel7) // Test "a != 0". .iinc(1, 3) .label(expectedLabel8) // Common exit. .go(expectedLabel2) .label() .label(expectedLabel9) // Second instantiation of subroutine. .astore(2) .iload(1) .ifne(expectedLabel10) .iinc(1, 2) .go(expectedLabel11) .label(expectedLabel10) // Test "a != 0". .iinc(1, 3) .label(expectedLabel11) // Common exit. .go(expectedLabel4) .label() .trycatch(expectedLabel0, expectedLabel1, expectedLabel1) .trycatch(expectedLabel3, expectedLabel5, expectedLabel1) .build(); assertEquals(toText(expectedMethod), toText(inlinedMethod)); assertDoesNotThrow(() -> buildClassWithMethod(inlinedMethod).newInstance()); } /** * Tests a method which has a lookupswitch or tableswitch w/in the finally clause. More * specifically: * * 
   * public void a() {
   *   int a = 0;
   *   try {
   *     a++;
   *   } finally {
   *     switch (a) {
   *       case 0:
   *         a += 2;
   *         break;
   *       default:
   *         a += 3;
   *     }
   *   }
   * }
   *
*/ @ParameterizedTest @ValueSource(strings = {"true", "false"}) void testInlineJsr_lookupOrTableSwitchInFinally(final boolean useTableSwitch) { MethodNode inputMethod = new MethodNodeBuilder(1, 4) .iconst_0() .istore(1) .label(label0) // Body of try block. .iinc(1, 1) .go(label6) .label(label1) // Exception handler. .astore(3) .jsr(label2) .aload(3) .athrow() .label(label2) // Subroutine. .astore(2) .iload(1) .switchto(label4, 0, label3, useTableSwitch) .label(label3) // First switch case. .iinc(1, 2) .go(label5) .label(label4) // Default switch case. .iinc(1, 3) .label(label5) // Common exit. .ret(2) .label(label6) // Non-exceptional exit from try block. .jsr(label2) .label(label7) .vreturn() .trycatch(label0, label1, label1) .trycatch(label6, label7, label1) .build(); MethodNode inlinedMethod = new MethodNode(Opcodes.ACC_PUBLIC, "m", "()V", null, null); inputMethod.accept( new JSRInlinerAdapter(inlinedMethod, Opcodes.ACC_PUBLIC, "m", "()V", null, null)); MethodNode expectedMethod = new MethodNodeBuilder(1, 4) .iconst_0() .istore(1) .label(expectedLabel0) // Try/catch block. .iinc(1, 1) .go(expectedLabel3) .label(expectedLabel1) // Exception handler. .astore(3) .aconst_null() .go(expectedLabel6) .label(expectedLabel2) .aload(3) .athrow() .label(expectedLabel3) // On non-exceptional exit, try block leads here. .aconst_null() .go(expectedLabel10) .label(expectedLabel4) .label(expectedLabel5) .vreturn() .label(expectedLabel6) // First instantiation of subroutine. .astore(2) .iload(1) .switchto(expectedLabel8, 0, expectedLabel7, useTableSwitch) .label(expectedLabel7) // First switch case. .iinc(1, 2) .go(expectedLabel9) .label(expectedLabel8) // Default switch case. .iinc(1, 3) .label(expectedLabel9) // Common exit. .go(expectedLabel2) .label() .label(expectedLabel10) // Second instantiation of subroutine. .astore(2) .iload(1) .switchto(expectedLabel12, 0, expectedLabel11, useTableSwitch) .label(expectedLabel11) // First switch case. .iinc(1, 2) .go(expectedLabel13) .label(expectedLabel12) // Default switch case. .iinc(1, 3) .label(expectedLabel13) // Common exit. .go(expectedLabel4) .label() .trycatch(expectedLabel0, expectedLabel1, expectedLabel1) .trycatch(expectedLabel3, expectedLabel5, expectedLabel1) .build(); assertEquals(toText(expectedMethod), toText(inlinedMethod)); assertDoesNotThrow(() -> buildClassWithMethod(inlinedMethod).newInstance()); } /** * Tests a simple nested finally. More specifically: * * 
   * public void a1() {
   *   int a = 0;
   *   try {
   *     a += 1;
   *   } finally {
   *     try {
   *       a += 2;
   *     } finally {
   *       a += 3;
   *     }
   *   }
   * }
   *
*/ @Test void testInlineJsr_simpleNestedFinally() { MethodNode inputMethod = new MethodNodeBuilder(2, 6) .iconst_0() .istore(1) .label(label0) // Body of try block. .iinc(1, 1) .jsr(label2) .go(label5) .label(label1) // First exception handler. .jsr(label2) .athrow() .label(label2) // First subroutine. .astore(2) .iinc(1, 2) .jsr(label4) .ret(2) .label(label3) // Second exception handler. .jsr(label4) .athrow() .label(label4) // Second subroutine. .astore(3) .iinc(1, 3) .ret(3) .label(label5) // On normal exit, try block jumps here. .vreturn() .trycatch(label0, label1, label1) .trycatch(label2, label3, label3) .build(); MethodNode inlinedMethod = new MethodNode(Opcodes.ACC_PUBLIC, "m", "()V", null, null); inputMethod.accept( new JSRInlinerAdapter(inlinedMethod, Opcodes.ACC_PUBLIC, "m", "()V", null, null)); MethodNode expectedMethod = new MethodNodeBuilder(2, 6) .iconst_0() .istore(1) .label(expectedLabel0) // Body of try block. .iinc(1, 1) .aconst_null() .go(expectedLabel5) .label(expectedLabel1) .go(expectedLabel4) .label(expectedLabel2) // First exception handler. .aconst_null() .go(expectedLabel9) .label(expectedLabel3) .athrow() .label(expectedLabel4) // On normal exit, try block jumps here. .vreturn() .label(expectedLabel5) // First instantiation of first subroutine. .astore(2) .iinc(1, 2) .aconst_null() .go(expectedLabel13) .label(expectedLabel6) .go(expectedLabel1) .label(expectedLabel7) .aconst_null() .go(expectedLabel14) .label(expectedLabel8) .athrow() .label() .label(expectedLabel9) // Second instantiation of first subroutine. .astore(2) .iinc(1, 2) .aconst_null() .go(expectedLabel15) .label(expectedLabel10) .go(expectedLabel3) .label(expectedLabel11) .aconst_null() .go(expectedLabel16) .label(expectedLabel12) .athrow() .label() .label(expectedLabel13) // First instantiation of second subroutine. .astore(3) .iinc(1, 3) .go(expectedLabel6) .label() .label(expectedLabel14) // Second instantiation of second subroutine. .astore(3) .iinc(1, 3) .go(expectedLabel8) .label() .label(expectedLabel15) // Third instantiation of second subroutine. .astore(3) .iinc(1, 3) .go(expectedLabel10) .label() .label(expectedLabel16) // Fourth instantiation of second subroutine. .astore(3) .iinc(1, 3) .go(expectedLabel12) .label() .trycatch(expectedLabel0, expectedLabel2, expectedLabel2) .trycatch(expectedLabel5, expectedLabel7, expectedLabel7) .trycatch(expectedLabel9, expectedLabel11, expectedLabel11) .build(); assertEquals(toText(expectedMethod), toText(inlinedMethod)); assertDoesNotThrow(() -> buildClassWithMethod(inlinedMethod).newInstance()); } /** * This tests a subroutine which has no ret statement, but ends in a "return" instead. * *

We structure this as a try/finally with a break in the finally. Because the while loop is * infinite, it's clear from the byte code that the only path which reaches the RETURN instruction * is through the subroutine. * * 

   * public void a1() {
   *   int a = 0;
   *   while (true) {
   *     try {
   *       a += 1;
   *     } finally {
   *       a += 2;
   *       break;
   *     }
   *   }
   * }
   *
*/ @Test void testInlineJsr_subroutineWithNoRet() { MethodNode inputMethod = new MethodNodeBuilder(1, 4) .iconst_0() .istore(1) .label(label0) // While loop header/try block. .iinc(1, 1) .jsr(label2) .go(label3) .label(label1) // Implicit catch block. .astore(2) .jsr(label2) .aload(2) .athrow() .label(label2) // Subroutine ... .astore(3) .iinc(1, 2) .go(label4) // ... note that it does not return! .label(label3) // End of the loop... goes back to the top! .go(label0) .label(label4) .vreturn() .trycatch(label0, label1, label1) .build(); MethodNode inlinedMethod = new MethodNode(Opcodes.ACC_PUBLIC, "m", "()V", null, null); inputMethod.accept( new JSRInlinerAdapter(inlinedMethod, Opcodes.ACC_PUBLIC, "m", "()V", null, null)); MethodNode expectedMethod = new MethodNodeBuilder(1, 4) .iconst_0() .istore(1) .label(expectedLabel0) // While loop header/try block. .iinc(1, 1) .aconst_null() .go(expectedLabel5) .label(expectedLabel1) .go(expectedLabel4) .label(expectedLabel2) // Implicit catch block. .astore(2) .aconst_null() .go(expectedLabel7) .label(expectedLabel3) .aload(2) .athrow() .label(expectedLabel4) // End of the loop... goes back to the top! .go(expectedLabel0) .label() .label(expectedLabel5) // First instantiation of subroutine ... .astore(3) .iinc(1, 2) .go(expectedLabel6) // ... note that it does not return! .label(expectedLabel6) .vreturn() .label(expectedLabel7) // Second instantiation of subroutine ... .astore(3) .iinc(1, 2) .go(expectedLabel8) // ... note that it does not return! .label(expectedLabel8) .vreturn() .trycatch(expectedLabel0, expectedLabel2, expectedLabel2) .build(); assertEquals(toText(expectedMethod), toText(inlinedMethod)); assertDoesNotThrow(() -> buildClassWithMethod(inlinedMethod).newInstance()); } /** * This tests a subroutine which has no ret statement, but ends in a "return" instead. The code * after the JSR appears to fall through the end of the method, but is in fact unreachable and * therefore valid. * * 
   *   JSR L0
   *   GOTO L1
   * L0:
   *   ASTORE 0
   *   RETURN
   * L1:
   *   ACONST_NULL
   *
*/ @Test void testInlineJsr_subroutineWithNoRet2() { MethodNode inputMethod = new MethodNodeBuilder(1, 1) .jsr(label0) .go(label1) .label(label0) .astore(0) .vreturn() .label(label1) .aconst_null() .build(); MethodNode inlinedMethod = new MethodNode(Opcodes.ACC_PUBLIC, "m", "()V", null, null); inputMethod.accept( new JSRInlinerAdapter(inlinedMethod, Opcodes.ACC_PUBLIC, "m", "()V", null, null)); MethodNode expectedMethod = new MethodNodeBuilder(1, 1) .aconst_null() .go(expectedLabel2) .label(expectedLabel0) .go(expectedLabel1) .label(expectedLabel1) .aconst_null() .label(expectedLabel2) // First instantiation of subroutine. .astore(0) .vreturn() .label() .build(); assertEquals(toText(expectedMethod), toText(inlinedMethod)); assertDoesNotThrow(() -> buildClassWithMethod(inlinedMethod).newInstance()); } /** * This tests a subroutine which has no ret statement, but instead exits implicitly by branching * to code which is not part of the subroutine. (Sadly, this is legal) * *

We structure this as a try/finally in a loop with a break in the finally. The loop is not * trivially infinite, so the RETURN statement is reachable both from the JSR subroutine and from * the main entry point. * * 

   * public void a1() {
   *   int a = 0;
   *   while (null == null) {
   *     try {
   *       a += 1;
   *     } finally {
   *       a += 2;
   *       break;
   *     }
   *   }
   * }
   *
*/ @Test void testInlineJsr_implicitExit() { MethodNode inputMethod = new MethodNodeBuilder(1, 4) .iconst_0() .istore(1) .label(label0) // While loop header. .aconst_null() .ifnonnull(label5) .label(label1) // Try block. .iinc(1, 1) .jsr(label3) .go(label4) .label(label2) // Implicit catch block. .astore(2) .jsr(label3) .aload(2) .athrow() .label(label3) // Subroutine ... .astore(3) .iinc(1, 2) .go(label5) // ... note that it does not return! .label(label4) // End of the loop... goes back to the top! .go(label1) .label(label5) .vreturn() .trycatch(label1, label2, label2) .build(); MethodNode inlinedMethod = new MethodNode(Opcodes.ACC_PUBLIC, "m", "()V", null, null); inputMethod.accept( new JSRInlinerAdapter(inlinedMethod, Opcodes.ACC_PUBLIC, "m", "()V", null, null)); MethodNode expectedMethod = new MethodNodeBuilder(1, 4) .iconst_0() .istore(1) .label(expectedLabel0) // While loop header. .aconst_null() .ifnonnull(expectedLabel6) .label(expectedLabel1) // While loop header/try block. .iinc(1, 1) .aconst_null() .go(expectedLabel7) .label(expectedLabel2) .go(expectedLabel5) .label(expectedLabel3) // Implicit catch block. .astore(2) .aconst_null() .go(expectedLabel8) .label(expectedLabel4) .aload(2) .athrow() .label(expectedLabel5) // End of the loop... goes back to the top! .go(expectedLabel1) .label(expectedLabel6) // Exit, not part of subroutine. // Note that the two subroutine instantiations branch here. .vreturn() .label(expectedLabel7) // First instantiation of subroutine ... .astore(3) .iinc(1, 2) .go(expectedLabel6) // ... note that it does not return! .label() .label(expectedLabel8) // Second instantiation of subroutine ... .astore(3) .iinc(1, 2) .go(expectedLabel6) // ... note that it does not return! .label() .trycatch(expectedLabel1, expectedLabel3, expectedLabel3) .build(); assertEquals(toText(expectedMethod), toText(inlinedMethod)); assertDoesNotThrow(() -> buildClassWithMethod(inlinedMethod).newInstance()); } /** * Tests a nested try/finally with implicit exit from one subroutine to the other subroutine. * Equivalent to the following java code: * * 
   * void m(boolean b) {
   *   try {
   *     return;
   *   } finally {
   *     while (b) {
   *       try {
   *         return;
   *       } finally {
   *         // NOTE --- this break avoids the second return above (weird)
   *         if (b) {
   *           break;
   *         }
   *       }
   *     }
   *   }
   * }
   *
* *

This example is from the paper, "Subroutine Inlining and Bytecode Abstraction to Simplify * Static and Dynamic Analysis" by Cyrille Artho and Armin Biere. */ @Test void testInlineJsr_implicitExitToAnotherSubroutine() { MethodNode inputMethod = new MethodNodeBuilder(1, 6) .iconst_0() .istore(1) .label(label0) // First try. .jsr(label2) .vreturn() .label(label1) // Exception handler for first try. .astore(LOCAL2) .jsr(label2) .aload(LOCAL2) .athrow() .label(label2) // First finally handler. .astore(LOCAL4) .go(label6) .label(label3) // Body of while loop, also second try. .jsr(label5) .vreturn() .label(label4) // Exception handler for second try. .astore(LOCAL3) .jsr(label5) .aload(LOCAL3) .athrow() .label(label5) // Second finally handler. .astore(LOCAL5) .iload(LOCAL1) .ifne(label7) .ret(LOCAL5) .label(label6) // Test for the while loop. .iload(LOCAL1) .ifne(label3) // Falls through. .label(label7) // Exit from finally block. .ret(LOCAL4) .trycatch(label0, label1, label1) .trycatch(label3, label4, label4) .build(); MethodNode inlinedMethod = new MethodNode(Opcodes.ACC_PUBLIC, "m", "()V", null, null); inputMethod.accept( new JSRInlinerAdapter(inlinedMethod, Opcodes.ACC_PUBLIC, "m", "()V", null, null)); MethodNode expectedMethod = new MethodNodeBuilder(1, 6) // --- Main Subroutine --- .iconst_0() .istore(1) .label(expectedLabel0) // First try. .aconst_null() .go(expectedLabel4) .label(expectedLabel1) .vreturn() .label(expectedLabel2) // Exception handler for first try. .astore(LOCAL2) .aconst_null() .go(expectedLabel11) .label(expectedLabel3) .aload(LOCAL2) .athrow() .label() // --- First instantiation of first subroutine --- .label(expectedLabel4) // First finally handler. .astore(LOCAL4) .go(expectedLabel9) .label(expectedLabel5) // Body of while loop, also second try. .aconst_null() .go(expectedLabel18) .label(expectedLabel6) .vreturn() .label(expectedLabel7) // Exception handler for second try. .astore(LOCAL3) .aconst_null() .go(expectedLabel19) .label(expectedLabel8) .aload(LOCAL3) .athrow() .label(expectedLabel9) // Test for the while loop. .iload(LOCAL1) .ifne(expectedLabel5) // Falls through. .label(expectedLabel10) // Exit from finally block. .go(expectedLabel1) // --- Second instantiation of first subroutine --- .label(expectedLabel11) // First finally handler. .astore(LOCAL4) .go(expectedLabel16) .label(expectedLabel12) // Body of while loop, also second try. .aconst_null() .go(expectedLabel20) .label(expectedLabel13) .vreturn() .label(expectedLabel14) // Exception handler for second try. .astore(LOCAL3) .aconst_null() .go(expectedLabel21) .label(expectedLabel15) .aload(LOCAL3) .athrow() .label(expectedLabel16) // Test for the while loop. .iload(LOCAL1) .ifne(expectedLabel12) // Falls through. .label(expectedLabel17) // Exit from finally block. .go(expectedLabel3) // --- Second subroutine's 4 instantiations --- .label(expectedLabel18) // First instantiation. .astore(LOCAL5) .iload(LOCAL1) .ifne(expectedLabel10) .go(expectedLabel6) .label() .label(expectedLabel19) // Second instantiation. .astore(LOCAL5) .iload(LOCAL1) .ifne(expectedLabel10) .go(expectedLabel8) .label() .label(expectedLabel20) // Third instantiation. .astore(LOCAL5) .iload(LOCAL1) .ifne(expectedLabel17) .go(expectedLabel13) .label() .label(expectedLabel21) // Fourth instantiation. .astore(LOCAL5) .iload(LOCAL1) .ifne(expectedLabel17) .go(expectedLabel15) .label() .trycatch(expectedLabel0, expectedLabel2, expectedLabel2) .trycatch(expectedLabel5, expectedLabel7, expectedLabel7) .trycatch(expectedLabel12, expectedLabel14, expectedLabel14) .build(); assertEquals(toText(expectedMethod), toText(inlinedMethod)); assertDoesNotThrow(() -> buildClassWithMethod(inlinedMethod).newInstance()); } /** * This tests two subroutines, neither of which exit. Instead, they both branch to a common set of * code which returns from the method. This code is not reachable except through these * subroutines, and since they do not invoke each other, it must be copied into both of them. * *

I don't believe this can be represented in Java. */ @Test void testInlineJsr_commonCodeWhichMustBeDuplicated() { MethodNode inputMethod = new MethodNodeBuilder(1, 2) .iconst_0() .istore(1) // Invoke the two subroutines, each twice. .jsr(label0) .jsr(label0) .jsr(label1) .jsr(label1) .vreturn() .label(label0) // Subroutine 1. .iinc(1, 1) .go(label2) // ... note that it does not return! .label(label1) // Subroutine 2. .iinc(1, 2) .go(label2) // ... note that it does not return! .label(label2) // Common code to both subroutines: exit method. .vreturn() .build(); MethodNode inlinedMethod = new MethodNode(Opcodes.ACC_PUBLIC, "m", "()V", null, null); inputMethod.accept( new JSRInlinerAdapter(inlinedMethod, Opcodes.ACC_PUBLIC, "m", "()V", null, null)); MethodNode expectedMethod = new MethodNodeBuilder(1, 2) .iconst_0() .istore(1) // Invoke the two subroutines, each twice. .aconst_null() .go(expectedLabel4) .label(expectedLabel0) .aconst_null() .go(expectedLabel6) .label(expectedLabel1) .aconst_null() .go(expectedLabel8) .label(expectedLabel2) .aconst_null() .go(expectedLabel10) .label(expectedLabel3) .vreturn() .label() .label(expectedLabel4) // Instantiation 1 of subroutine 1. .iinc(1, 1) .go(expectedLabel5) // ... note that it does not return! .label(expectedLabel5) .vreturn() .label(expectedLabel6) // Instantiation 2 of subroutine 1. .iinc(1, 1) .go(expectedLabel7) // ... note that it does not return! .label(expectedLabel7) .vreturn() .label(expectedLabel8) // Instantiation 1 of subroutine 2. .iinc(1, 2) .go(expectedLabel9) // ...note that it does not return! .label(expectedLabel9) .vreturn() .label(expectedLabel10) // Instantiation 2 of subroutine 2. .iinc(1, 2) .go(expectedLabel11) // ... note that it does not return! .label(expectedLabel11) .vreturn() .build(); assertEquals(toText(expectedMethod), toText(inlinedMethod)); assertDoesNotThrow(() -> buildClassWithMethod(inlinedMethod).newInstance()); } /** * This tests a simple subroutine where the control flow jumps back and forth between the * subroutine and the caller. * *

This would not normally be produced by a java compiler. */ @Test void testInlineJsr_interleavedCode() { MethodNode inputMethod = new MethodNodeBuilder(1, 3) .iconst_0() .istore(1) // Invoke the subroutine, each twice. .jsr(label0) .go(label1) .label(label0) // Subroutine 1. .astore(2) .iinc(1, 1) .go(label2) .label(label1) // Second part of main subroutine. .iinc(1, 2) .go(label3) .label(label2) // Second part of subroutine 1. .iinc(1, 4) .ret(2) .label(label3) // Third part of main subroutine. .jsr(label0) .vreturn() .build(); MethodNode inlinedMethod = new MethodNode(Opcodes.ACC_PUBLIC, "m", "()V", null, null); inputMethod.accept( new JSRInlinerAdapter(inlinedMethod, Opcodes.ACC_PUBLIC, "m", "()V", null, null)); MethodNode expectedMethod = new MethodNodeBuilder(1, 3) // Main routine. .iconst_0() .istore(1) .aconst_null() .go(expectedLabel4) .label(expectedLabel0) .go(expectedLabel1) .label(expectedLabel1) .iinc(1, 2) .go(expectedLabel2) .label(expectedLabel2) .aconst_null() .go(expectedLabel6) .label(expectedLabel3) .vreturn() .label(expectedLabel4) // Instantiation #1. .astore(2) .iinc(1, 1) .go(expectedLabel5) .label(expectedLabel5) .iinc(1, 4) .go(expectedLabel0) .label() .label(expectedLabel6) // Instantiation #2. .astore(2) .iinc(1, 1) .go(expectedLabel7) .label(expectedLabel7) .iinc(1, 4) .go(expectedLabel3) .label() .build(); assertEquals(toText(expectedMethod), toText(inlinedMethod)); assertDoesNotThrow(() -> buildClassWithMethod(inlinedMethod).newInstance()); } /** * Tests a nested try/finally with implicit exit from one subroutine to the other subroutine, and * with a surrounding try/catch thrown in the mix. Equivalent to the following java code: * * 

   * void m(int b) {
   *   try {
   *     try {
   *       return;
   *     } finally {
   *       while (b) {
   *         try {
   *           return;
   *         } finally {
   *           // NOTE --- this break avoids the second return above (weird)
   *           if (b) {
   *             break;
   *           }
   *         }
   *       }
   *     }
   *   } catch (Exception e) {
   *     b += 3;
   *     return;
   *   }
   * }
   *
*/ @Test void testInlineJsr_implicitExitInTryCatch() { MethodNode inputMethod = new MethodNodeBuilder(1, 6) .iconst_0() .istore(1) .label(label0) // Outermost try. .label(label1) // First try. .jsr(label3) .vreturn() .label(label2) // Exception handler for first try. .astore(LOCAL2) .jsr(label3) .aload(LOCAL2) .athrow() .label(label3) // First finally handler. .astore(LOCAL4) .go(label7) .label(label4) // Body of while loop, also second try. .jsr(label6) .vreturn() .label(label5) // Exception handler for second try. .astore(LOCAL3) .jsr(label6) .aload(LOCAL3) .athrow() .label(label6) // Second finally handler. .astore(LOCAL5) .iload(LOCAL1) .ifne(label8) .ret(LOCAL5) .label(label7) // Test for the while loop. .iload(LOCAL1) .ifne(label4) // Falls through. .label(label8) // Exit from finally block. .ret(LOCAL4) .label(label9) // Outermost catch. .iinc(LOCAL1, 3) .vreturn() .trycatch(label1, label2, label2) .trycatch(label4, label5, label5) .trycatch(label0, label9, label9) .build(); MethodNode inlinedMethod = new MethodNode(Opcodes.ACC_PUBLIC, "m", "()V", null, null); inputMethod.accept( new JSRInlinerAdapter(inlinedMethod, Opcodes.ACC_PUBLIC, "m", "()V", null, null)); MethodNode expectedMethod = new MethodNodeBuilder(1, 6) // --- Main Subroutine --- .iconst_0() .istore(1) .label(expectedLabel0) // Outermost try / first try. .aconst_null() .go(expectedLabel5) .label(expectedLabel1) .vreturn() .label(expectedLabel2) // Exception handler for first try. .astore(LOCAL2) .aconst_null() .go(expectedLabel13) .label(expectedLabel3) .aload(LOCAL2) .athrow() .label(expectedLabel4) // Outermost catch. .iinc(LOCAL1, 3) .vreturn() // --- First instantiation of first subroutine --- .label(expectedLabel5) // First finally handler. .astore(LOCAL4) .go(expectedLabel10) .label(expectedLabel6) // Body of while loop, also second try. .aconst_null() .go(expectedLabel21) .label(expectedLabel7) .vreturn() .label(expectedLabel8) // Exception handler for second try. .astore(LOCAL3) .aconst_null() .go(expectedLabel23) .label(expectedLabel9) .aload(LOCAL3) .athrow() .label(expectedLabel10) // Test for the while loop. .iload(LOCAL1) .ifne(expectedLabel6) // Falls through. .label(expectedLabel11) // Exit from finally block. .go(expectedLabel1) .label(expectedLabel12) // --- Second instantiation of first subroutine --- .label(expectedLabel13) // First finally handler. .astore(LOCAL4) .go(expectedLabel18) .label(expectedLabel14) // Body of while loop, also second try. .aconst_null() .go(expectedLabel25) .label(expectedLabel15) .vreturn() .label(expectedLabel16) // Exception handler for second try. .astore(LOCAL3) .aconst_null() .go(expectedLabel27) .label(expectedLabel17) .aload(LOCAL3) .athrow() .label(expectedLabel18) // Test for the while loop. .iload(LOCAL1) .ifne(expectedLabel14) // Falls through. .label(expectedLabel19) // Exit from finally block. .go(expectedLabel3) .label(expectedLabel20) // --- Second subroutine's 4 instantiations --- .label(expectedLabel21) .astore(LOCAL5) .iload(LOCAL1) .ifne(expectedLabel11) .go(expectedLabel7) .label(expectedLabel22) .label(expectedLabel23) .astore(LOCAL5) .iload(LOCAL1) .ifne(expectedLabel11) .go(expectedLabel9) .label(expectedLabel24) .label(expectedLabel25) .astore(LOCAL5) .iload(LOCAL1) .ifne(expectedLabel19) .go(expectedLabel15) .label(expectedLabel26) .label(expectedLabel27) .astore(LOCAL5) .iload(LOCAL1) .ifne(expectedLabel19) .go(expectedLabel17) .label(expectedLabel28) // Main subroutine handlers. .trycatch(expectedLabel0, expectedLabel2, expectedLabel2) .trycatch(expectedLabel0, expectedLabel4, expectedLabel4) // First instance of first subroutine try/catch handlers. // Note: reuses handler code from main subroutine. .trycatch(expectedLabel6, expectedLabel8, expectedLabel8) .trycatch(expectedLabel5, expectedLabel12, expectedLabel4) // Second instance of first sub try/catch handlers. .trycatch(expectedLabel14, expectedLabel16, expectedLabel16) .trycatch(expectedLabel13, expectedLabel20, expectedLabel4) // All 4 instances of second subroutine. .trycatch(expectedLabel21, expectedLabel22, expectedLabel4) .trycatch(expectedLabel23, expectedLabel24, expectedLabel4) .trycatch(expectedLabel25, expectedLabel26, expectedLabel4) .trycatch(expectedLabel27, expectedLabel28, expectedLabel4) .build(); assertEquals(toText(expectedMethod), toText(inlinedMethod)); assertDoesNotThrow(() -> buildClassWithMethod(inlinedMethod).newInstance()); } /** * Tests an example coming from distilled down version of * com/sun/corba/ee/impl/protocol/CorbaClientDelegateImpl from GlassFish 2. See issue #317823. */ @Test void testInlineJsr_glassFish2CorbaClientDelegateImplExample() { MethodNode inputMethod = new MethodNodeBuilder(3, 3) .label(label0) .jsr(label4) .label(label1) .go(label5) .label(label2) .pop() .jsr(label4) .label(label3) .aconst_null() .athrow() .label(label4) .astore(1) .ret(1) .label(label5) .aconst_null() .aconst_null() .aconst_null() .pop() .pop() .pop() .label(label6) .go(label8) .label(label7) .pop() .go(label8) .aconst_null() .athrow() .label(label8) .iconst_0() .ifne(label0) .jsr(label12) .label(label9) .vreturn() .label(label10) .pop() .jsr(label12) .label(label11) .aconst_null() .athrow() .label(label12) .astore(2) .ret(2) .trycatch(label0, label1, label2) .trycatch(label2, label3, label2) .trycatch(label0, label6, label7) .trycatch(label0, label9, label10) .trycatch(label10, label11, label10) .build(); MethodNode inlinedMethod = new MethodNode(Opcodes.ACC_PUBLIC, "m", "()V", null, null); inputMethod.accept( new JSRInlinerAdapter(inlinedMethod, Opcodes.ACC_PUBLIC, "m", "()V", null, null)); MethodNode expectedMethod = new MethodNodeBuilder(3, 3) // --- Main Subroutine --- .label(expectedLabel0) .aconst_null() .go(expectedLabel15) .label(expectedLabel1) .label(expectedLabel2) .go(expectedLabel6) .label(expectedLabel3) .pop() .aconst_null() .go(expectedLabel17) .label(expectedLabel4) .label(expectedLabel5) .aconst_null() .athrow() .label(expectedLabel6) .aconst_null() .aconst_null() .aconst_null() .pop() .pop() .pop() .label(expectedLabel7) .go(expectedLabel9) .label(expectedLabel8) .pop() .go(expectedLabel9) // [some dead code skipped here] .label(expectedLabel9) .iconst_0() .ifne(expectedLabel0) .aconst_null() .go(expectedLabel19) .label(expectedLabel10) .label(expectedLabel11) .vreturn() .label(expectedLabel12) .pop() .aconst_null() .go(expectedLabel20) .label(expectedLabel13) .label(expectedLabel14) .aconst_null() .athrow() // --- First instantiation of first subroutine --- .label() .label(expectedLabel15) .astore(1) .go(expectedLabel1) .label(expectedLabel16) // --- Second instantiation of first subroutine --- .label(expectedLabel17) .astore(1) .go(expectedLabel4) .label(expectedLabel18) // --- First instantiation of second subroutine --- .label(expectedLabel19) .astore(2) .go(expectedLabel10) // --- Second instantiation of second subroutine --- .label(expectedLabel20) .astore(2) .go(expectedLabel13) .trycatch(expectedLabel0, expectedLabel2, expectedLabel3) .trycatch(expectedLabel3, expectedLabel5, expectedLabel3) .trycatch(expectedLabel0, expectedLabel7, expectedLabel8) .trycatch(expectedLabel0, expectedLabel11, expectedLabel12) .trycatch(expectedLabel12, expectedLabel14, expectedLabel12) .trycatch(expectedLabel15, expectedLabel16, expectedLabel8) .trycatch(expectedLabel15, expectedLabel16, expectedLabel12) .trycatch(expectedLabel17, expectedLabel18, expectedLabel8) .trycatch(expectedLabel17, expectedLabel18, expectedLabel12) .build(); assertEquals(toText(expectedMethod), toText(inlinedMethod)); assertDoesNotThrow(() -> buildClassWithMethod(inlinedMethod).newInstance()); } /** * Tests a method which has line numbers and local variable declarations. More specifically: * * 
   *   public void a() {
   * 1   int a = 0;
   * 2   try {
   * 3     a++;
   * 4   } finally {
   * 5     a--;
   * 6   }
   *   }
   *   LV "a" from 1 to 6
   *
*/ @Test void testInlineJsr_basicLineNumberAndLocalVars() { MethodNode inputMethod = new MethodNodeBuilder(1, 4) .label(label0) .line(1, label0) .iconst_0() .istore(1) .label(label1) // Body of try block. .line(3, label1) .iinc(1, 1) .go(label4) .label(label2) // Exception handler. .astore(3) .jsr(label3) .aload(3) .athrow() .label(label3) // Subroutine. .line(5, label3) .astore(2) .iinc(1, -1) .ret(2) .label(label4) // Non-exceptional exit from try block. .jsr(label3) .label(label5) .vreturn() .trycatch(label1, label2, label2) .trycatch(label4, label5, label2) .localvar("a", "I", 1, label0, label5) .build(); MethodNode inlinedMethod = new MethodNode(Opcodes.ACC_PUBLIC, "m", "()V", null, null); inputMethod.accept( new JSRInlinerAdapter(inlinedMethod, Opcodes.ACC_PUBLIC, "m", "()V", null, null)); MethodNode expectedMethod = new MethodNodeBuilder(1, 4) .label(expectedLabel0) .line(1, expectedLabel0) .iconst_0() .istore(1) .label(expectedLabel1) // Try/catch block. .line(3, expectedLabel1) .iinc(1, 1) .go(expectedLabel4) .label(expectedLabel2) // Exception handler. .astore(3) .aconst_null() .go(expectedLabel7) .label(expectedLabel3) .aload(3) .athrow() .label(expectedLabel4) // On non-exceptional exit, try block leads here. .aconst_null() .go(expectedLabel9) .label(expectedLabel5) .label(expectedLabel6) .vreturn() .label(expectedLabel7) // First instantiation of subroutine. .line(5, expectedLabel7) .astore(2) .iinc(1, -1) .go(expectedLabel3) .label(expectedLabel8) .label(expectedLabel9) // Second instantiation of subroutine. .line(5, expectedLabel9) .astore(2) .iinc(1, -1) .go(expectedLabel5) .label(expectedLabel10) .trycatch(expectedLabel1, expectedLabel2, expectedLabel2) .trycatch(expectedLabel4, expectedLabel6, expectedLabel2) .localvar("a", "I", 1, expectedLabel0, expectedLabel6) .localvar("a", "I", 1, expectedLabel7, expectedLabel8) .localvar("a", "I", 1, expectedLabel9, expectedLabel10) .build(); assertEquals(toText(expectedMethod), toText(inlinedMethod)); assertDoesNotThrow(() -> buildClassWithMethod(inlinedMethod).newInstance()); } /** Tests that classes transformed with JSRInlinerAdapter can be loaded and instantiated. */ @ParameterizedTest @MethodSource(ALL_CLASSES_AND_LATEST_API) void testInlineJsr_precompiledClass( final PrecompiledClass classParameter, final Api apiParameter) { ClassReader classReader = new ClassReader(classParameter.getBytes()); ClassWriter classWriter = new ClassWriter(0); classReader.accept(new JsrInlinerClassAdapter(apiParameter.value(), classWriter), 0); ClassFile classFile = new ClassFile(classWriter.toByteArray()); if (classParameter.isNotCompatibleWithCurrentJdk()) { assertThrows(UnsupportedClassVersionError.class, () -> classFile.newInstance()); } else { assertDoesNotThrow(() -> classFile.newInstance()); } } static class JsrInlinerClassAdapter extends ClassVisitor { JsrInlinerClassAdapter(final int api, final ClassVisitor classVisitor) { super(api, classVisitor); } @Override public MethodVisitor visitMethod( final int access, final String name, final String descriptor, final String signature, final String[] exceptions) { MethodVisitor methodVisitor = super.visitMethod(access, name, descriptor, signature, exceptions); return new JSRInlinerAdapter( api, methodVisitor, access, name, descriptor, signature, exceptions) {}; } } }