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jvmjasmin

Useless store causing crash

I have this jasmin assembly, which is the equivalent of the simplification of JVM assembly produced by a bytecode rewriter I am writing. It crashes when run, but works if I remove the sipush and the first store.

.method public simple()V
    .limit stack 4
    sipush        12345
    istore_1
    getstatic java/lang/System/out Ljava/io/PrintStream;
    sipush        12345
    ldc 12345
    iadd
    invokevirtual java/io/PrintStream/println(I)V
    return
.end method

Does the JVM require every store to be used by a load?

Solution

  • istore_1 stores a value to the local variable #1, but your methods has no locals.

    The method will become valid if you add the following line:

        .limit locals 2