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how to map bytecodes to methods?

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Mariano Martinez Peck

how to map bytecodes to methods?

Hi. I am new with all these stuff. My problem is how to map bytecodes numbers to methods.

For example, if in a method I send #class and see the bytecodes I can see it has a "C7", which in decimal is 199.
If I see Interpreter class >> initializeBytecodeTable then in 199 I see #bytecodePrimClass which is correct.

Now....I want to go in the OTHER direction. For example, I have changed something in #bytecodePrimValueWithArg and I would like to know WHICH method from the image side, generates that bytecode.
Ok, sometimes it is intuitive, but sometimes more or less...

Thanks

Mariano

Eliot Miranda-2

Re: how to map bytecodes to methods?

On Tue, Oct 5, 2010 at 10:44 AM, Mariano Martinez Peck <[hidden email]> wrote:

Hi. I am new with all these stuff. My problem is how to map bytecodes numbers to methods.

For example, if in a method I send #class and see the bytecodes I can see it has a "C7", which in decimal is 199.
If I see Interpreter class >> initializeBytecodeTable then in 199 I see #bytecodePrimClass which is correct.

Now....I want to go in the OTHER direction. For example, I have changed something in #bytecodePrimValueWithArg and I would like to know WHICH method from the image side, generates that bytecode.

See VariableNode class>>initialize:

StdSelectors := Dictionary new: 64.

encoder

fillDict: StdSelectors

with: SelectorNode

mapping: ((1 to: Smalltalk specialSelectorSize) collect:

[:i | Smalltalk specialSelectorAt: i])

to: (SendPlus to: SendPlus + 31).

Ok, sometimes it is intuitive, but sometimes more or less...

Thanks

Mariano