mirror of
https://github.com/python/cpython.git
synced 2024-12-11 10:50:11 +08:00
9de7ec7868
This patch by Antoine Pitrou optimizes the bytecode for conditional branches by
merging the following "POP_TOP" instruction into the conditional jump. For
example, the list comprehension "[x for x in l if not x]" produced the
following bytecode:
1 0 BUILD_LIST 0
3 LOAD_FAST 0 (.0)
>> 6 FOR_ITER 23 (to 32)
9 STORE_FAST 1 (x)
12 LOAD_FAST 1 (x)
15 JUMP_IF_TRUE 10 (to 28)
18 POP_TOP
19 LOAD_FAST 1 (x)
22 LIST_APPEND 2
25 JUMP_ABSOLUTE 6
>> 28 POP_TOP
29 JUMP_ABSOLUTE 6
>> 32 RETURN_VALUE
but after the patch it produces the following bytecode:
1 0 BUILD_LIST 0
3 LOAD_FAST 0 (.0)
>> 6 FOR_ITER 18 (to 27)
9 STORE_FAST 1 (x)
12 LOAD_FAST 1 (x)
15 POP_JUMP_IF_TRUE 6
18 LOAD_FAST 1 (x)
21 LIST_APPEND 2
24 JUMP_ABSOLUTE 6
>> 27 RETURN_VALUE
Notice that not only the code is shorter, but the conditional jump
(POP_JUMP_IF_TRUE) jumps right to the start of the loop instead of going through
the JUMP_ABSOLUTE at the end. "continue" statements are helped
similarly.
Furthermore, the old jump opcodes (JUMP_IF_FALSE, JUMP_IF_TRUE) have been
replaced by two new opcodes:
- JUMP_IF_TRUE_OR_POP, which jumps if true and pops otherwise
- JUMP_IF_FALSE_OR_POP, which jumps if false and pops otherwise
178 lines
4.9 KiB
Python
178 lines
4.9 KiB
Python
|
|
"""
|
|
opcode module - potentially shared between dis and other modules which
|
|
operate on bytecodes (e.g. peephole optimizers).
|
|
"""
|
|
|
|
__all__ = ["cmp_op", "hasconst", "hasname", "hasjrel", "hasjabs",
|
|
"haslocal", "hascompare", "hasfree", "opname", "opmap",
|
|
"HAVE_ARGUMENT", "EXTENDED_ARG"]
|
|
|
|
cmp_op = ('<', '<=', '==', '!=', '>', '>=', 'in', 'not in', 'is',
|
|
'is not', 'exception match', 'BAD')
|
|
|
|
hasconst = []
|
|
hasname = []
|
|
hasjrel = []
|
|
hasjabs = []
|
|
haslocal = []
|
|
hascompare = []
|
|
hasfree = []
|
|
|
|
opmap = {}
|
|
opname = [''] * 256
|
|
for op in range(256): opname[op] = '<%r>' % (op,)
|
|
del op
|
|
|
|
def def_op(name, op):
|
|
opname[op] = name
|
|
opmap[name] = op
|
|
|
|
def name_op(name, op):
|
|
def_op(name, op)
|
|
hasname.append(op)
|
|
|
|
def jrel_op(name, op):
|
|
def_op(name, op)
|
|
hasjrel.append(op)
|
|
|
|
def jabs_op(name, op):
|
|
def_op(name, op)
|
|
hasjabs.append(op)
|
|
|
|
# Instruction opcodes for compiled code
|
|
# Blank lines correspond to available opcodes
|
|
|
|
def_op('STOP_CODE', 0)
|
|
def_op('POP_TOP', 1)
|
|
def_op('ROT_TWO', 2)
|
|
def_op('ROT_THREE', 3)
|
|
def_op('DUP_TOP', 4)
|
|
def_op('ROT_FOUR', 5)
|
|
|
|
def_op('NOP', 9)
|
|
def_op('UNARY_POSITIVE', 10)
|
|
def_op('UNARY_NEGATIVE', 11)
|
|
def_op('UNARY_NOT', 12)
|
|
|
|
def_op('UNARY_INVERT', 15)
|
|
|
|
def_op('BINARY_POWER', 19)
|
|
def_op('BINARY_MULTIPLY', 20)
|
|
|
|
def_op('BINARY_MODULO', 22)
|
|
def_op('BINARY_ADD', 23)
|
|
def_op('BINARY_SUBTRACT', 24)
|
|
def_op('BINARY_SUBSCR', 25)
|
|
def_op('BINARY_FLOOR_DIVIDE', 26)
|
|
def_op('BINARY_TRUE_DIVIDE', 27)
|
|
def_op('INPLACE_FLOOR_DIVIDE', 28)
|
|
def_op('INPLACE_TRUE_DIVIDE', 29)
|
|
|
|
def_op('STORE_MAP', 54)
|
|
def_op('INPLACE_ADD', 55)
|
|
def_op('INPLACE_SUBTRACT', 56)
|
|
def_op('INPLACE_MULTIPLY', 57)
|
|
|
|
def_op('INPLACE_MODULO', 59)
|
|
def_op('STORE_SUBSCR', 60)
|
|
def_op('DELETE_SUBSCR', 61)
|
|
def_op('BINARY_LSHIFT', 62)
|
|
def_op('BINARY_RSHIFT', 63)
|
|
def_op('BINARY_AND', 64)
|
|
def_op('BINARY_XOR', 65)
|
|
def_op('BINARY_OR', 66)
|
|
def_op('INPLACE_POWER', 67)
|
|
def_op('GET_ITER', 68)
|
|
def_op('STORE_LOCALS', 69)
|
|
|
|
def_op('PRINT_EXPR', 70)
|
|
def_op('LOAD_BUILD_CLASS', 71)
|
|
|
|
def_op('INPLACE_LSHIFT', 75)
|
|
def_op('INPLACE_RSHIFT', 76)
|
|
def_op('INPLACE_AND', 77)
|
|
def_op('INPLACE_XOR', 78)
|
|
def_op('INPLACE_OR', 79)
|
|
def_op('BREAK_LOOP', 80)
|
|
def_op('WITH_CLEANUP', 81)
|
|
|
|
def_op('RETURN_VALUE', 83)
|
|
def_op('IMPORT_STAR', 84)
|
|
|
|
def_op('YIELD_VALUE', 86)
|
|
def_op('POP_BLOCK', 87)
|
|
def_op('END_FINALLY', 88)
|
|
def_op('POP_EXCEPT', 89)
|
|
|
|
HAVE_ARGUMENT = 90 # Opcodes from here have an argument:
|
|
|
|
name_op('STORE_NAME', 90) # Index in name list
|
|
name_op('DELETE_NAME', 91) # ""
|
|
def_op('UNPACK_SEQUENCE', 92) # Number of tuple items
|
|
jrel_op('FOR_ITER', 93)
|
|
def_op('UNPACK_EX', 94)
|
|
name_op('STORE_ATTR', 95) # Index in name list
|
|
name_op('DELETE_ATTR', 96) # ""
|
|
name_op('STORE_GLOBAL', 97) # ""
|
|
name_op('DELETE_GLOBAL', 98) # ""
|
|
def_op('DUP_TOPX', 99) # number of items to duplicate
|
|
def_op('LOAD_CONST', 100) # Index in const list
|
|
hasconst.append(100)
|
|
name_op('LOAD_NAME', 101) # Index in name list
|
|
def_op('BUILD_TUPLE', 102) # Number of tuple items
|
|
def_op('BUILD_LIST', 103) # Number of list items
|
|
def_op('BUILD_SET', 104) # Number of set items
|
|
def_op('BUILD_MAP', 105) # Number of dict entries (upto 255)
|
|
name_op('LOAD_ATTR', 106) # Index in name list
|
|
def_op('COMPARE_OP', 107) # Comparison operator
|
|
hascompare.append(107)
|
|
name_op('IMPORT_NAME', 108) # Index in name list
|
|
name_op('IMPORT_FROM', 109) # Index in name list
|
|
|
|
jrel_op('JUMP_FORWARD', 110) # Number of bytes 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('JUMP_ABSOLUTE', 113) # ""
|
|
jabs_op('POP_JUMP_IF_FALSE', 114) # ""
|
|
jabs_op('POP_JUMP_IF_TRUE', 115) # ""
|
|
|
|
name_op('LOAD_GLOBAL', 116) # Index in name list
|
|
|
|
jabs_op('CONTINUE_LOOP', 119) # Target address
|
|
jrel_op('SETUP_LOOP', 120) # Distance to target address
|
|
jrel_op('SETUP_EXCEPT', 121) # ""
|
|
jrel_op('SETUP_FINALLY', 122) # ""
|
|
|
|
def_op('LOAD_FAST', 124) # Local variable number
|
|
haslocal.append(124)
|
|
def_op('STORE_FAST', 125) # Local variable number
|
|
haslocal.append(125)
|
|
def_op('DELETE_FAST', 126) # Local variable number
|
|
haslocal.append(126)
|
|
|
|
def_op('RAISE_VARARGS', 130) # Number of raise arguments (1, 2, or 3)
|
|
def_op('CALL_FUNCTION', 131) # #args + (#kwargs << 8)
|
|
def_op('MAKE_FUNCTION', 132) # Number of args with default values
|
|
def_op('BUILD_SLICE', 133) # Number of items
|
|
def_op('MAKE_CLOSURE', 134)
|
|
def_op('LOAD_CLOSURE', 135)
|
|
hasfree.append(135)
|
|
def_op('LOAD_DEREF', 136)
|
|
hasfree.append(136)
|
|
def_op('STORE_DEREF', 137)
|
|
hasfree.append(137)
|
|
|
|
def_op('CALL_FUNCTION_VAR', 140) # #args + (#kwargs << 8)
|
|
def_op('CALL_FUNCTION_KW', 141) # #args + (#kwargs << 8)
|
|
def_op('CALL_FUNCTION_VAR_KW', 142) # #args + (#kwargs << 8)
|
|
def_op('EXTENDED_ARG', 143)
|
|
EXTENDED_ARG = 143
|
|
|
|
def_op('LIST_APPEND', 145)
|
|
def_op('SET_ADD', 146)
|
|
def_op('MAP_ADD', 147)
|
|
|
|
|
|
del def_op, name_op, jrel_op, jabs_op
|