Broken bytecode for nested try statements

Issue #242 resolved
Jesper Öqvist created an issue

ExtendJ 8.0.1-240-g3d86145 Java SE 8

Broken bytecode is generated for this test:

// Test try-statement control flow.
public class Test {
  public static void main(String[] args) throws Exception {
    System.out.println(new Test().run());

  public int run() throws Exception {
    int result = -1;
    try {
      try {
        return result;
      } finally {
        result = 0;
    } catch(Exception ex) {
      return result;

Expected result: should print "-1"

Actual result: fails to run:

    [junit] [FAIL] runTest[run/try_06](tests.extendj.TestJava7)
    [junit] Error output files differ expected:<[]> but was:<[Error: A JNI error has occurred, please check your installation and try again
    [junit] Exception in thread "main" java.lang.VerifyError: Expecting a stackmap frame at branch target 15
    [junit] Exception Details:
    [junit]   Location:
    [junit] @2: iload_2
    [junit]   Reason:
    [junit]     Expected stackmap frame at this location.
    [junit]   Bytecode:
    [junit]     0x0000000: 023d 1c3c 033d 1bac 4e03 3d2d bf00 004e
    [junit]     0x0000010: 1cac                                   
    [junit]   Exception Handler Table:
    [junit]     bci [2, 8] => handler: 8
    [junit]     bci [2, 15] => handler: 15
    [junit]   Stackmap Table:
    [junit]     full_frame(@8,{Object[#2],Top,Integer},{Object[#44]})
    [junit]     same_locals_1_stack_item_frame(@13,Object[#37])

Comments (2)

  1. Jesper Öqvist reporter

    This error occurs because an exception entry jumps to a block that will be expanded. The exception handler position should be changed to the new start position for the basic block.

  2. Jesper Öqvist reporter

    Update exception handler after deleting block

    This improves the handling of exception ranges after deleting basic blocks. The handler label is now updated when merging a block with a previous deleted block. Also improved trimming ranges after deleting a block.

    fixes #242 (bitbucket)

    → <<cset 58987e28ef71>>

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