- confusing line_offset parameter -> first_line parameter
- systematically test and fix new file parameter
- remove redundant Bytecode.show_info() API
- rename Bytecode.display_code() to Bytecode.dis() and have it
return the multi-line string rather than printing it directly
- eliminated some not-so-helpful helpers from the bytecode_helper
test support module
Also fixed a longstanding defect (worked around in the test suite)
where lines emitted by the dis module could include trailing white
space. That no longer happens, allowing the formatting tests to be
simplified to use plain string comparisons.
* get_instructions generator
* ability to redirect output to a file
* Bytecode and Instruction abstractions
Patch by Nick Coghlan, Ryan Kelly and Thomas Kluyver.
namespace if it occurs as a free variable in a nested block. This limitation
of the compiler has been lifted, and a new opcode introduced (DELETE_DEREF).
This sample was valid in 2.6, but fails to compile in 3.x without this change::
>>> def f():
... def print_error():
... print(e)
... try:
... something
... except Exception as e:
... print_error()
... # implicit "del e" here
This sample has always been invalid in Python, and now works::
>>> def outer(x):
... def inner():
... return x
... inner()
... del x
There is no need to bump the PYC magic number: the new opcode is used
for code that did not compile before.
reality it's simply an implementation detail for CPython. This point is now
clearly documented in both the docs for dis and the glossary.
Closes issue #7829. Thanks to Terry Reedy for some initial suggestions on
wording.
svn+ssh://pythondev@svn.python.org/python/trunk
........
r72912 | benjamin.peterson | 2009-05-25 08:13:44 -0500 (Mon, 25 May 2009) | 5 lines
add a SETUP_WITH opcode
It speeds up the with statement and correctly looks up the special
methods involved.
........
r72920 | benjamin.peterson | 2009-05-25 15:12:57 -0500 (Mon, 25 May 2009) | 1 line
take into account the fact that SETUP_WITH pushes a finally block
........
r72940 | benjamin.peterson | 2009-05-26 07:49:59 -0500 (Tue, 26 May 2009) | 1 line
teach the peepholer about SETUP_WITH
........
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
Berker Peksag
Benjamin Peterson
Serhiy Storchaka
Nick Coghlan
R David Murray
Larry Hastings
Georg Brandl
Ezio Melotti
Andrew Svetlov
Eli Bendersky
Raymond Hettinger
Antoine Pitrou
Éric Araujo
Amaury Forgeot d'Arc
Brett Cannon
Jeffrey Yasskin