see code emitted by bytecode, native, viper decorators?

[pbljung]

How do I see the code emitted by decorators bytecode, native or viper?

In "normal" python I can see the bytecode with foo.func_code.co_code, or import dis and use dis.dis(foo).
I would like to see the dis-like output that D. George shows on https://gotocon.com/dl/goto-amsterdam-2 ... Things.pdf
How do I do that?

[dhylands]

If you add this line to ports/stm32/mpconfigport.h:

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#define MICROPY_DEBUG_PRINTERS (1)

and then edit py/emitglue.c and change the initial value of mp_verbose_flag to 2: https://github.com/micropython/micropyt ... glue.c#L49

Then when code is compiled it will show the bytecode:

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>>> def foo():
...     print('test')
... 
File <stdin>, code block '<module>' (descriptor: 20003080, bytecode @20003260 21 bytes)
Raw bytecode (code_info_size=7, bytecode_size=14):
 01 00 00 00 00 00 07 46 00 4d 00 00 00 ff 60 00
 24 8d 05 11 5b
arg names:
(N_STATE 1)
(N_EXC_STACK 0)
  bc=-1 line=1
00 MAKE_FUNCTION 20003090
02 STORE_NAME foo
05 LOAD_CONST_NONE
06 RETURN_VALUE
File <stdin>, code block 'foo' (descriptor: 20003090, bytecode @20003280 26 bytes)
Raw bytecode (code_info_size=8, bytecode_size=18):
 02 00 00 00 00 00 08 8d 05 4d 00 21 00 00 ff 1c
 04 04 16 8e 05 64 01 32 11 5b
arg names:
(N_STATE 2)
(N_EXC_STACK 0)
  bc=-1 line=1
  bc=0 line=2
00 LOAD_GLOBAL print
03 LOAD_CONST_STRING 'test'
06 CALL_FUNCTION n=1 nkw=0
08 POP_TOP
09 LOAD_CONST_NONE
10 RETURN_VALUE
>>> 

The first bit of bytecode is the REPL storing the function foo and the second bit is the foo function itself.

[dhylands]

I'm not sure how you see native or viper code.

[Jongy]

I found this topic after I watched https://www.youtube.com/watch?v=hHec4qL00x0, played around with "dis" in cpython and thought "hey that's quite cool"

Any plans on adding a real "dis"-like module? I don't think it's a long way from the current "mp_bytecode_print" function.

[jimmo]

Not what you're looking for but a very cool feature that was added recently is sys.settrace. You can use it to extract the bytecode from a function. Disassembly still left as an exercise for the reader, but could potentially be done in a separate tool. Unfortunately doesn't work for native/viper/asm though.

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import sys

def foo(a, b):
    x = a + b
    return x

def trace(frame, event, arg):
    print(event, frame.f_code.co_name, frame.f_code.co_code)

sys.settrace(trace)
foo(1, 2)
sys.settrace(None)

prints

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call foo b'\xb0\xb1\xf2\xc2\xb2c'