VerifyError appears with boolean method and long or larger primitive type in conditional operand of ternary statement

A very small addition. The method does not have to be boolean returning. Even the following fails with the same error:

class Foo {
    long id
    def bar() {
        return (id ? "a" : "b")
    }
}   
println Foo.class

All the following cases fail too:

class Foo {
    long id = 0
    def bar() {
    	assert id, "Done"
    }
}   
println new Foo().bar()

class Foo {
    long id = 0
    def bar() {
        while(id){
            print "here"
            break
        }
    }
}   
println new Foo().bar()

class Foo {
    long id = 0
    def bar() {
        if(id) {
        	true
        } else {
        	false
        }
    }
}   
println new Foo().bar()

So, basically most of the places where boolean expressions are being evaluated. I am not 100% sure yet, but I think it is happening because jump instruction in all such cases is written as "mv.visitJumpInsn(IFEQ, l0);", meaning read the value of the boolean expression off the stack as an int. If the value that is put on the stack is bigger than int, then all these cases run into issues.

I am not much familiar with ASM and right now, I don't know if instead of IFEQ, we can use some other OpCode for larger-than-int types. If I come to know anything on that, I will write again. (I may be wrong on the above analysis - not much familiar with ASM !)

Fixed.

The bytecode instructions to do box/booleanUnbox were not getting written in the class in the scenarios identified in this JIRA.

Before the change, for the boolean expression condition check, the bytecode instructions looked like:

4:   aload_0
5:   getfield    #50; //Field id:J
8:   ifeq    17

In the above case, the class verification is failing because what is being stored on the stack is of type long but then it is read as in int in ifeq operation.

After the fix, the bytecode instructions look like:

4:   aload_0
5:   getfield    #50; //Field id:J
8:   invokestatic    #56; //Method org/codehaus/groovy/runtime/typehandling/DefaultTypeTransformation.box:(J)Ljava/lang/Object;
11:  invokestatic    #60; //Method org/codehaus/groovy/runtime/typehandling/DefaultTypeTransformation.booleanUnbox:(Ljava/lang/Object;)Z
14:  ifeq    23

With the box/booleanUnbox, what ifeq sees is unboxed boolean value and it works fine.