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Merged
merged 11 commits into from
Sep 1, 2022
Merged

gh-93554: Conditional jumps only jump forward #96318

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c9e1106
transform conditional backward branches
iritkatriel Aug 26, 2022
28e8bbd
remove directed conditional branch opcodes
iritkatriel Aug 26, 2022
5c983d8
update dis.rst
iritkatriel Aug 26, 2022
bf1c52f
Merge remote-tracking branch 'upstream/main' into conditional_jump_on…
iritkatriel Aug 26, 2022
8a3d017
use basicblock_last_instr
iritkatriel Aug 26, 2022
97a80aa
add news
iritkatriel Aug 26, 2022
718025d
Merge remote-tracking branch 'upstream/main' into conditional_jump_on…
iritkatriel Aug 30, 2022
22e0b30
fix versionadded in dis.rst
iritkatriel Aug 31, 2022
e31029b
Merge remote-tracking branch 'upstream/main' into conditional_jump_on…
iritkatriel Aug 31, 2022
35a47ee
Merge remote-tracking branch 'upstream/main' into conditional_jump_on…
iritkatriel Sep 1, 2022
e87887c
magic number
iritkatriel Sep 1, 2022
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56 changes: 20 additions & 36 deletions Doc/library/dis.rst
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Original file line number Diff line number Diff line change
Expand Up @@ -999,60 +999,48 @@ iterations of the loop.
.. versionadded:: 3.11


.. opcode:: POP_JUMP_FORWARD_IF_TRUE (delta)
.. opcode:: POP_JUMP_IF_TRUE (delta)

If TOS is true, increments the bytecode counter by *delta*. TOS is popped.

.. versionadded:: 3.11


.. opcode:: POP_JUMP_BACKWARD_IF_TRUE (delta)

If TOS is true, decrements the bytecode counter by *delta*. TOS is popped.

.. versionadded:: 3.11
.. versionchanged:: 3.11
The oparg is now a relative delta rather than an absolute target.
This opcode is a pseudo-instruction, replaced in final bytecode by
the directed versions (forward/backward).

.. versionchanged:: 3.12
This is no longer a pseudo-instruction.

.. opcode:: POP_JUMP_FORWARD_IF_FALSE (delta)
.. opcode:: POP_JUMP_IF_FALSE (delta)

If TOS is false, increments the bytecode counter by *delta*. TOS is popped.

.. versionadded:: 3.11


.. opcode:: POP_JUMP_BACKWARD_IF_FALSE (delta)

If TOS is false, decrements the bytecode counter by *delta*. TOS is popped.

.. versionadded:: 3.11
.. versionchanged:: 3.11
The oparg is now a relative delta rather than an absolute target.
This opcode is a pseudo-instruction, replaced in final bytecode by
the directed versions (forward/backward).

.. versionchanged:: 3.12
This is no longer a pseudo-instruction.

.. opcode:: POP_JUMP_FORWARD_IF_NOT_NONE (delta)
.. opcode:: POP_JUMP_IF_NOT_NONE (delta)

If TOS is not ``None``, increments the bytecode counter by *delta*. TOS is popped.

.. versionadded:: 3.11


.. opcode:: POP_JUMP_BACKWARD_IF_NOT_NONE (delta)

If TOS is not ``None``, decrements the bytecode counter by *delta*. TOS is popped.

.. versionadded:: 3.11
.. versionchanged:: 3.12
This is no longer a pseudo-instruction.


.. opcode:: POP_JUMP_FORWARD_IF_NONE (delta)
.. opcode:: POP_JUMP_IF_NONE (delta)

If TOS is ``None``, increments the bytecode counter by *delta*. TOS is popped.

.. versionadded:: 3.11


.. opcode:: POP_JUMP_BACKWARD_IF_NONE (delta)

If TOS is ``None``, decrements the bytecode counter by *delta*. TOS is popped.

.. versionadded:: 3.11
.. versionchanged:: 3.12
This is no longer a pseudo-instruction.


.. opcode:: JUMP_IF_TRUE_OR_POP (delta)
Expand Down Expand Up @@ -1433,10 +1421,6 @@ but are replaced by real opcodes or removed before bytecode is generated.

.. opcode:: JUMP
.. opcode:: JUMP_NO_INTERRUPT
.. opcode:: POP_JUMP_IF_FALSE
.. opcode:: POP_JUMP_IF_TRUE
.. opcode:: POP_JUMP_IF_NONE
.. opcode:: POP_JUMP_IF_NOT_NONE

Undirected relative jump instructions which are replaced by their
directed (forward/backward) counterparts by the assembler.
Expand Down
46 changes: 21 additions & 25 deletions Include/internal/pycore_opcode.h
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40 changes: 14 additions & 26 deletions Include/opcode.h
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3 changes: 2 additions & 1 deletion Lib/importlib/_bootstrap_external.py
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Expand Up @@ -412,6 +412,7 @@ def _write_atomic(path, data, mode=0o666):
# Python 3.12a1 3506 (Add BINARY_SLICE and STORE_SLICE instructions)
# Python 3.12a1 3507 (Set lineno of module's RESUME to 0)
# Python 3.12a1 3508 (Add CLEANUP_THROW)
# Python 3.12a1 3509 (Conditional jumps only jump forward)

# Python 3.13 will start with 3550

Expand All @@ -424,7 +425,7 @@ def _write_atomic(path, data, mode=0o666):
# Whenever MAGIC_NUMBER is changed, the ranges in the magic_values array
# in PC/launcher.c must also be updated.

MAGIC_NUMBER = (3508).to_bytes(2, 'little') + b'\r\n'
MAGIC_NUMBER = (3509).to_bytes(2, 'little') + b'\r\n'

_RAW_MAGIC_NUMBER = int.from_bytes(MAGIC_NUMBER, 'little') # For import.c

Expand Down
19 changes: 6 additions & 13 deletions Lib/opcode.py
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Expand Up @@ -153,8 +153,8 @@ def pseudo_op(name, op, real_ops):
jrel_op('JUMP_FORWARD', 110) # Number of words to skip
jrel_op('JUMP_IF_FALSE_OR_POP', 111) # Number of words to skip
jrel_op('JUMP_IF_TRUE_OR_POP', 112) # ""
jrel_op('POP_JUMP_FORWARD_IF_FALSE', 114)
jrel_op('POP_JUMP_FORWARD_IF_TRUE', 115)
jrel_op('POP_JUMP_IF_FALSE', 114)
jrel_op('POP_JUMP_IF_TRUE', 115)
name_op('LOAD_GLOBAL', 116) # Index in name list
def_op('IS_OP', 117)
def_op('CONTAINS_OP', 118)
Expand All @@ -170,8 +170,8 @@ def pseudo_op(name, op, real_ops):
haslocal.append(126)
def_op('LOAD_FAST_CHECK', 127) # Local variable number
haslocal.append(127)
jrel_op('POP_JUMP_FORWARD_IF_NOT_NONE', 128)
jrel_op('POP_JUMP_FORWARD_IF_NONE', 129)
jrel_op('POP_JUMP_IF_NOT_NONE', 128)
jrel_op('POP_JUMP_IF_NONE', 129)
def_op('RAISE_VARARGS', 130) # Number of raise arguments (1, 2, or 3)
def_op('GET_AWAITABLE', 131)
def_op('MAKE_FUNCTION', 132) # Flags
Expand Down Expand Up @@ -216,10 +216,6 @@ def pseudo_op(name, op, real_ops):
def_op('KW_NAMES', 172)
hasconst.append(172)

jrel_op('POP_JUMP_BACKWARD_IF_NOT_NONE', 173)
jrel_op('POP_JUMP_BACKWARD_IF_NONE', 174)
jrel_op('POP_JUMP_BACKWARD_IF_FALSE', 175)
jrel_op('POP_JUMP_BACKWARD_IF_TRUE', 176)

hasarg.extend([op for op in opmap.values() if op >= HAVE_ARGUMENT])

Expand All @@ -235,11 +231,8 @@ def pseudo_op(name, op, real_ops):

pseudo_op('JUMP', 260, ['JUMP_FORWARD', 'JUMP_BACKWARD'])
pseudo_op('JUMP_NO_INTERRUPT', 261, ['JUMP_FORWARD', 'JUMP_BACKWARD_NO_INTERRUPT'])
pseudo_op('POP_JUMP_IF_FALSE', 262, ['POP_JUMP_FORWARD_IF_FALSE', 'POP_JUMP_BACKWARD_IF_FALSE'])
pseudo_op('POP_JUMP_IF_TRUE', 263, ['POP_JUMP_FORWARD_IF_TRUE', 'POP_JUMP_BACKWARD_IF_TRUE'])
pseudo_op('POP_JUMP_IF_NONE', 264, ['POP_JUMP_FORWARD_IF_NONE', 'POP_JUMP_BACKWARD_IF_NONE'])
pseudo_op('POP_JUMP_IF_NOT_NONE', 265, ['POP_JUMP_FORWARD_IF_NOT_NONE', 'POP_JUMP_BACKWARD_IF_NOT_NONE'])
pseudo_op('LOAD_METHOD', 266, ['LOAD_ATTR'])

pseudo_op('LOAD_METHOD', 262, ['LOAD_ATTR'])

MAX_PSEUDO_OPCODE = MIN_PSEUDO_OPCODE + len(_pseudo_ops) - 1

Expand Down
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