bpo-47120: make POP_JUMP_IF_TRUE/FALSE/NONE/NOT_NONE relative (GH-32400)

Author: iritkatriel

Doc/library/dis.rst

@@ -937,30 +937,58 @@ iterations of the loop.
    .. versionadded:: 3.11
 
 
-.. opcode:: POP_JUMP_IF_TRUE (target)
+.. opcode:: POP_JUMP_FORWARD_IF_TRUE (delta)
 
-   If TOS is true, sets the bytecode counter to *target*.  TOS is popped.
+   If TOS is true, increments the bytecode counter by *delta*.  TOS is popped.
 
-   .. versionadded:: 3.1
+   .. versionadded:: 3.11
 
 
-.. opcode:: POP_JUMP_IF_FALSE (target)
+.. opcode:: POP_JUMP_BACKWARD_IF_TRUE (delta)
 
-   If TOS is false, sets the bytecode counter to *target*.  TOS is popped.
+   If TOS is true, decrements the bytecode counter by *delta*.  TOS is popped.
 
-   .. versionadded:: 3.1
+   .. versionadded:: 3.11
+
+
+.. opcode:: POP_JUMP_FORWARD_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
+
+
+.. opcode:: POP_JUMP_FORWARD_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
 
 
-.. opcode:: POP_JUMP_IF_NOT_NONE (target)
+.. opcode:: POP_JUMP_FORWARD_IF_NONE (delta)
 
-   If TOS is not none, sets the bytecode counter to *target*.  TOS is popped.
+   If TOS is ``None``, increments the bytecode counter by *delta*.  TOS is popped.
 
    .. versionadded:: 3.11
 
 
-.. opcode:: POP_JUMP_IF_NONE (target)
+.. opcode:: POP_JUMP_BACKWARD_IF_NONE (delta)
 
-   If TOS is none, sets the bytecode counter to *target*.  TOS is popped.
+   If TOS is ``None``, decrements the bytecode counter by *delta*.  TOS is popped.
 
    .. versionadded:: 3.11
 

Doc/whatsnew/3.11.rst

@@ -750,9 +750,6 @@ CPython bytecode changes
   ``ROT_TWO``, ``ROT_THREE``, ``ROT_FOUR``, and ``ROT_N``) with new
   :opcode:`COPY` and :opcode:`SWAP` instructions.
 
-* Add :opcode:`POP_JUMP_IF_NOT_NONE` and :opcode:`POP_JUMP_IF_NONE` opcodes to
-  speed up conditional jumps.
-
 * Replaced :opcode:`JUMP_IF_NOT_EXC_MATCH` by :opcode:`CHECK_EXC_MATCH` which
   performs the check but does not jump.
 
@@ -761,7 +758,17 @@ CPython bytecode changes
 
 * Replaced :opcode:`JUMP_ABSOLUTE` by the relative :opcode:`JUMP_BACKWARD`.
 
-* Added :opcode:`JUMP_BACKWARD_NO_INTERRUPT`, which is used in certain loops where it is undesirable to handle interrupts.
+* Added :opcode:`JUMP_BACKWARD_NO_INTERRUPT`, which is used in certain loops where it
+  is undesirable to handle interrupts.
+
+* Replaced :opcode:`POP_JUMP_IF_TRUE` and :opcode:`POP_JUMP_IF_FALSE` by
+  the relative :opcode:`POP_JUMP_FORWARD_IF_TRUE`, :opcode:`POP_JUMP_BACKWARD_IF_TRUE`,
+  :opcode:`POP_JUMP_FORWARD_IF_FALSE` and :opcode:`POP_JUMP_BACKWARD_IF_FALSE`.
+
+* Added :opcode:`POP_JUMP_FORWARD_IF_NOT_NONE`, :opcode:`POP_JUMP_BACKWARD_IF_NOT_NONE`,
+  :opcode:`POP_JUMP_FORWARD_IF_NONE` and :opcode:`POP_JUMP_BACKWARD_IF_NONE`
+  opcodes to speed up conditional jumps.
+
 
 Deprecated
 ==========

Include/opcode.h

@@ -392,6 +392,9 @@ def parse_exception_table(code):
     except StopIteration:
         return entries
 
+def _is_backward_jump(op):
+    return 'JUMP_BACKWARD' in opname[op]
+
 def _get_instructions_bytes(code, varname_from_oparg=None,
                             names=None, co_consts=None,
                             linestarts=None, line_offset=0,
@@ -442,7 +445,7 @@ def _get_instructions_bytes(code, varname_from_oparg=None,
                 argval = arg*2
                 argrepr = "to " + repr(argval)
             elif op in hasjrel:
-                signed_arg = -arg if op == JUMP_BACKWARD else arg
+                signed_arg = -arg if _is_backward_jump(op) else arg
                 argval = offset + 2 + signed_arg*2
                 argrepr = "to " + repr(argval)
             elif op in haslocal or op in hasfree:
@@ -568,7 +571,7 @@ def findlabels(code):
     for offset, op, arg in _unpack_opargs(code):
         if arg is not None:
             if op in hasjrel:
-                if op == JUMP_BACKWARD:
+                if _is_backward_jump(op):
                     arg = -arg
                 label = offset + 2 + arg*2
             elif op in hasjabs:

Lib/dis.py

@@ -400,6 +400,7 @@ def _write_atomic(path, data, mode=0o666):
 #     Python 3.11a6 3490 (remove JUMP_IF_NOT_EXC_MATCH, add CHECK_EXC_MATCH)
 #     Python 3.11a6 3491 (remove JUMP_IF_NOT_EG_MATCH, add CHECK_EG_MATCH,
 #                         add JUMP_BACKWARD_NO_INTERRUPT, make JUMP_NO_INTERRUPT virtual)
+#     Python 3.11a7 3492 (make POP_JUMP_IF_NONE/NOT_NONE/TRUE/FALSE relative)
 
 #     Python 3.12 will start with magic number 3500
 
@@ -414,7 +415,7 @@ 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 = (3491).to_bytes(2, 'little') + b'\r\n'
+MAGIC_NUMBER = (3492).to_bytes(2, 'little') + b'\r\n'
 _RAW_MAGIC_NUMBER = int.from_bytes(MAGIC_NUMBER, 'little')  # For import.c
 
 _PYCACHE = '__pycache__'

Lib/importlib/_bootstrap_external.py

@@ -133,8 +133,8 @@ def jabs_op(name, op, entries=0):
 jrel_op('JUMP_FORWARD', 110)    # Number of words to skip
 jabs_op('JUMP_IF_FALSE_OR_POP', 111) # Target byte offset from beginning of code
 jabs_op('JUMP_IF_TRUE_OR_POP', 112)  # ""
-jabs_op('POP_JUMP_IF_FALSE', 114)    # ""
-jabs_op('POP_JUMP_IF_TRUE', 115)     # ""
+jrel_op('POP_JUMP_FORWARD_IF_FALSE', 114)
+jrel_op('POP_JUMP_FORWARD_IF_TRUE', 115)
 name_op('LOAD_GLOBAL', 116, 5)     # Index in name list
 def_op('IS_OP', 117)
 def_op('CONTAINS_OP', 118)
@@ -148,8 +148,8 @@ def jabs_op(name, op, entries=0):
 haslocal.append(125)
 def_op('DELETE_FAST', 126)      # Local variable number
 haslocal.append(126)
-jabs_op('POP_JUMP_IF_NOT_NONE', 128)
-jabs_op('POP_JUMP_IF_NONE', 129)
+jrel_op('POP_JUMP_FORWARD_IF_NOT_NONE', 128)
+jrel_op('POP_JUMP_FORWARD_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
@@ -197,6 +197,11 @@ def jabs_op(name, op, entries=0):
 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)
+
 
 del def_op, name_op, jrel_op, jabs_op
 

Lib/opcode.py

@@ -373,7 +373,7 @@ def bug42562():
 
 %3d        LOAD_GLOBAL              0 (Exception)
            CHECK_EXC_MATCH
-           POP_JUMP_IF_FALSE       36 (to 72)
+           POP_JUMP_FORWARD_IF_FALSE    18 (to 72)
            STORE_FAST               0 (e)
 
 %3d        LOAD_FAST                0 (e)
@@ -685,7 +685,15 @@ def test_widths(self):
         for opcode, opname in enumerate(dis.opname):
             if opname in ('BUILD_MAP_UNPACK_WITH_CALL',
                           'BUILD_TUPLE_UNPACK_WITH_CALL',
-                          'JUMP_BACKWARD_NO_INTERRUPT'):
+                          'JUMP_BACKWARD_NO_INTERRUPT',
+                          'POP_JUMP_FORWARD_IF_NONE',
+                          'POP_JUMP_BACKWARD_IF_NONE',
+                          'POP_JUMP_FORWARD_IF_NOT_NONE',
+                          'POP_JUMP_BACKWARD_IF_NOT_NONE',
+                          'POP_JUMP_FORWARD_IF_TRUE',
+                          'POP_JUMP_BACKWARD_IF_TRUE',
+                          'POP_JUMP_FORWARD_IF_FALSE',
+                          'POP_JUMP_BACKWARD_IF_FALSE'):
                 continue
             with self.subTest(opname=opname):
                 width = dis._OPNAME_WIDTH
@@ -1227,12 +1235,12 @@ def _prepare_test_cases():
   Instruction(opname='LOAD_FAST', opcode=124, arg=0, argval='i', argrepr='i', offset=66, starts_line=5, is_jump_target=False, positions=None),
   Instruction(opname='LOAD_CONST', opcode=100, arg=2, argval=4, argrepr='4', offset=68, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='COMPARE_OP', opcode=107, arg=0, argval='<', argrepr='<', offset=70, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_JUMP_IF_FALSE', opcode=114, arg=40, argval=80, argrepr='to 80', offset=76, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_JUMP_FORWARD_IF_FALSE', opcode=114, arg=1, argval=80, argrepr='to 80', offset=76, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='JUMP_BACKWARD', opcode=140, arg=24, argval=32, argrepr='to 32', offset=78, starts_line=6, is_jump_target=False, positions=None),
   Instruction(opname='LOAD_FAST', opcode=124, arg=0, argval='i', argrepr='i', offset=80, starts_line=7, is_jump_target=True, positions=None),
   Instruction(opname='LOAD_CONST', opcode=100, arg=3, argval=6, argrepr='6', offset=82, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='COMPARE_OP', opcode=107, arg=4, argval='>', argrepr='>', offset=84, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_JUMP_IF_FALSE', opcode=114, arg=48, argval=96, argrepr='to 96', offset=90, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_JUMP_FORWARD_IF_FALSE', opcode=114, arg=2, argval=96, argrepr='to 96', offset=90, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=92, starts_line=8, is_jump_target=False, positions=None),
   Instruction(opname='JUMP_FORWARD', opcode=110, arg=16, argval=128, argrepr='to 128', offset=94, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='JUMP_BACKWARD', opcode=140, arg=33, argval=32, argrepr='to 32', offset=96, starts_line=7, is_jump_target=True, positions=None),
@@ -1242,7 +1250,7 @@ def _prepare_test_cases():
   Instruction(opname='CALL', opcode=171, arg=1, argval=1, argrepr='', offset=116, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=126, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='LOAD_FAST', opcode=124, arg=0, argval='i', argrepr='i', offset=128, starts_line=11, is_jump_target=True, positions=None),
-  Instruction(opname='POP_JUMP_IF_FALSE', opcode=114, arg=102, argval=204, argrepr='to 204', offset=130, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_JUMP_FORWARD_IF_FALSE', opcode=114, arg=36, argval=204, argrepr='to 204', offset=130, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='LOAD_GLOBAL', opcode=116, arg=3, argval='print', argrepr='NULL + print', offset=132, starts_line=12, is_jump_target=True, positions=None),
   Instruction(opname='LOAD_FAST', opcode=124, arg=0, argval='i', argrepr='i', offset=144, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='PRECALL', opcode=166, arg=1, argval=1, argrepr='', offset=146, starts_line=None, is_jump_target=False, positions=None),
@@ -1255,15 +1263,15 @@ def _prepare_test_cases():
   Instruction(opname='LOAD_FAST', opcode=124, arg=0, argval='i', argrepr='i', offset=172, starts_line=14, is_jump_target=False, positions=None),
   Instruction(opname='LOAD_CONST', opcode=100, arg=3, argval=6, argrepr='6', offset=174, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='COMPARE_OP', opcode=107, arg=4, argval='>', argrepr='>', offset=176, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_JUMP_IF_FALSE', opcode=114, arg=93, argval=186, argrepr='to 186', offset=182, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_JUMP_FORWARD_IF_FALSE', opcode=114, arg=1, argval=186, argrepr='to 186', offset=182, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='JUMP_BACKWARD', opcode=140, arg=29, argval=128, argrepr='to 128', offset=184, starts_line=15, is_jump_target=False, positions=None),
   Instruction(opname='LOAD_FAST', opcode=124, arg=0, argval='i', argrepr='i', offset=186, starts_line=16, is_jump_target=True, positions=None),
   Instruction(opname='LOAD_CONST', opcode=100, arg=2, argval=4, argrepr='4', offset=188, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='COMPARE_OP', opcode=107, arg=0, argval='<', argrepr='<', offset=190, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_JUMP_IF_FALSE', opcode=114, arg=100, argval=200, argrepr='to 200', offset=196, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_JUMP_FORWARD_IF_FALSE', opcode=114, arg=1, argval=200, argrepr='to 200', offset=196, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='JUMP_FORWARD', opcode=110, arg=17, argval=234, argrepr='to 234', offset=198, starts_line=17, is_jump_target=False, positions=None),
   Instruction(opname='LOAD_FAST', opcode=124, arg=0, argval='i', argrepr='i', offset=200, starts_line=11, is_jump_target=True, positions=None),
-  Instruction(opname='POP_JUMP_IF_TRUE', opcode=115, arg=66, argval=132, argrepr='to 132', offset=202, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_JUMP_BACKWARD_IF_TRUE', opcode=176, arg=36, argval=132, argrepr='to 132', offset=202, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='LOAD_GLOBAL', opcode=116, arg=3, argval='print', argrepr='NULL + print', offset=204, starts_line=19, is_jump_target=True, positions=None),
   Instruction(opname='LOAD_CONST', opcode=100, arg=6, argval='Who let lolcatz into this test suite?', argrepr="'Who let lolcatz into this test suite?'", offset=216, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='PRECALL', opcode=166, arg=1, argval=1, argrepr='', offset=218, starts_line=None, is_jump_target=False, positions=None),
@@ -1291,7 +1299,7 @@ def _prepare_test_cases():
   Instruction(opname='JUMP_FORWARD', opcode=110, arg=11, argval=328, argrepr='to 328', offset=304, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='PUSH_EXC_INFO', opcode=35, arg=None, argval=None, argrepr='', offset=306, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='WITH_EXCEPT_START', opcode=49, arg=None, argval=None, argrepr='', offset=308, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_JUMP_IF_TRUE', opcode=115, arg=160, argval=320, argrepr='to 320', offset=310, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_JUMP_FORWARD_IF_TRUE', opcode=115, arg=4, argval=320, argrepr='to 320', offset=310, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='RERAISE', opcode=119, arg=2, argval=2, argrepr='', offset=312, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='COPY', opcode=120, arg=3, argval=3, argrepr='', offset=314, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='POP_EXCEPT', opcode=89, arg=None, argval=None, argrepr='', offset=316, starts_line=None, is_jump_target=False, positions=None),
@@ -1304,7 +1312,7 @@ def _prepare_test_cases():
   Instruction(opname='PUSH_EXC_INFO', opcode=35, arg=None, argval=None, argrepr='', offset=330, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='LOAD_GLOBAL', opcode=116, arg=4, argval='ZeroDivisionError', argrepr='ZeroDivisionError', offset=332, starts_line=22, is_jump_target=False, positions=None),
   Instruction(opname='CHECK_EXC_MATCH', opcode=36, arg=None, argval=None, argrepr='', offset=344, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_JUMP_IF_FALSE', opcode=114, arg=192, argval=384, argrepr='to 384', offset=346, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_JUMP_FORWARD_IF_FALSE', opcode=114, arg=18, argval=384, argrepr='to 384', offset=346, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=348, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='LOAD_GLOBAL', opcode=116, arg=3, argval='print', argrepr='NULL + print', offset=350, starts_line=23, is_jump_target=False, positions=None),
   Instruction(opname='LOAD_CONST', opcode=100, arg=9, argval='Here we go, here we go, here we go...', argrepr="'Here we go, here we go, here we go...'", offset=362, starts_line=None, is_jump_target=False, positions=None),