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I can print an integer in jasmin like so:

getstatic java/lang/System/out Ljava/io/PrintStream;
bipush 7
invokevirtual java/io/PrintStream/println(I)V

What would the argument to println be to print a long (64-bit integer)?

I have tried invokevirtual java/io/PrintStream/println(L)V but the assembler tells me that (L)V is an illegal signature. (Note: System.out and a long are both on the stack when I try to call this method.)

Tyler Gaona
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2 Answers2

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I was previously having trouble with this as well. L is reserved for literal object names and can not be used to print longs. However, J can be used to print long (64 bit) values.

So, your code would just be:

getstatic java/lang/System/out Ljava/io/PrintStream; ldc2_w 7 invokevirtual java/io/PrintStream/println(J)V

Brady Sheehan
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You could use l2i to print small long (64 bit) values, but this could cause you to lose the sign bit and additional information. You should use

invokevirtual java/io/PrintStream/println(J)V

Brady Sheehan
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Clint
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