* Can now test for basic blocks.
* Optimize inverted comparisions.
* Optimize unary_not followed by a conditional jump.
* Added a new opcode, NOP, to keep code size constant.
* Applied NOP to previous transformations where appropriate.
Note, the NOP would not be necessary if other functions were
added to re-target jump addresses and update the co_lnotab mapping.
That would yield slightly faster and cleaner bytecode at the
expense of optimizer simplicity and of keeping it decoupled
from the line-numbering structure.
particular leaving the traceback object (and everything reachable
from it) alive throughout shutdown. The patch is mostly from Guido.
Bugfix candidate.
new line.
New pvt API function _Py_PrintReferenceAddresses(): Prints only the
addresses and refcnts of the live objects. This is always safe to call,
because it has no dependence on Python's C API.
Py_Finalize(): If envar PYTHONDUMPREFS is set, call (the new)
_Py_PrintReferenceAddresses() right before dumping final pymalloc stats.
We can't print the reprs of the objects here because too much of the
interpreter has been shut down. You need to correlate the addresses
displayed here with the object reprs printed by the earlier
PYTHONDUMPREFS call to _Py_PrintReferences().
New functions:
unsigned long PyInt_AsUnsignedLongMask(PyObject *);
unsigned PY_LONG_LONG) PyInt_AsUnsignedLongLongMask(PyObject *);
unsigned long PyLong_AsUnsignedLongMask(PyObject *);
unsigned PY_LONG_LONG) PyLong_AsUnsignedLongLongMask(PyObject *);
New and changed format codes:
b unsigned char 0..UCHAR_MAX
B unsigned char none **
h unsigned short 0..USHRT_MAX
H unsigned short none **
i int INT_MIN..INT_MAX
I * unsigned int 0..UINT_MAX
l long LONG_MIN..LONG_MAX
k * unsigned long none
L long long LLONG_MIN..LLONG_MAX
K * unsigned long long none
Notes:
* New format codes.
** Changed from previous "range-and-a-half" to "none"; the
range-and-a-half checking wasn't particularly useful.
New test test_getargs2.py, to verify all this.
PYTHONDUMPREFS output after most teardown. Attempts to use
PYTHONDUMPREFS with the Zope3 test suite died with Py_FatalError(),
since _Py_PrintReferences() can end up executing arbitrary Python code
(for objects that override __repr__), and that requires an intact
interpreter.
even farther down, to just before the call to
_PyObject_DebugMallocStats(). This required the following changes:
- pystate.c, PyThreadState_GetDict(): changed not to raise an
exception or issue a fatal error when no current thread state is
available, but simply return NULL without raising an exception
(ever).
- object.c, Py_ReprEnter(): when PyThreadState_GetDict() returns NULL,
don't raise an exception but return 0. This means that when
printing a container that's recursive, printing will go on and on
and on. But that shouldn't happen in the case we care about (see
first bullet).
- Updated Misc/NEWS and Doc/api/init.tex to reflect changes to
PyThreadState_GetDict() definition.
the code erroneously decrefed the istep argument in an error case. This
caused a co_consts tuple to lose a float constant prematurely, which
eventually caused gc to try executing static data in floatobject.c (don't
ask <wink>). So reworked this extensively to ensure refcount correctness.
- range() now works even if the arguments are longs with magnitude
larger than sys.maxint, as long as the total length of the sequence
fits. E.g., range(2**100, 2**101, 2**100) is the following list:
[1267650600228229401496703205376L]. (SF patch #707427.)
return. Setting an exception can mess with the exception state, and
continuing is definitely wrong (since type is dereferenced later on).
Some code that calls this seems to be prepared for a NULL exception
type, so let's be safe rather than sorry and simply assume there's
nothing to normalize in this case.
Adds a single function to improve generated bytecode. Has a single line
attachment point, so it is completely de-coupled from both the compiler
and ceval.c.
Makes three simple transforms that do not require a basic block analysis
or re-ordering of code. Gives improved timings on pystone, pybench,
and any code using either "while 1" or "x,y=y,x".
Arranged that all the objects exposed by __builtin__ appear in the list
of all objects. I basically peed away two days tracking down a mystery
leak in sys.gettotalrefcount() in a ZODB app (== tons of code), because
the object leaking the references didn't appear in the sys.getobjects(0)
list. The object happened to be False. Now False is in the list, along
with other popular & previously missing leak candidates (like None).
Alas, we still don't have a choke point covering *all* Python objects,
so the list of all objects may still be incomplete.
variables to store internal data. As a result, any atempts to use the
unicode system with multiple active interpreters, or successive
interpreter executions, would fail.
Now that information is stored into members of the PyInterpreterState
structure.
Added two predictions:
GET_ITER --> FOR_ITER
FOR_ITER --> STORE_FAST or UNPACK_SEQUENCE
Improves timings on pybench and timeit.py. Pystone results are neutral.
Applied to common cases:
COMPARE_OP is often followed by a JUMP_IF.
JUMP_IF is usually followed by POP_TOP.
Shows improved timings on PyStone, PyBench, and specific tests
using timeit.py:
python timeit.py -s "x=1" "if x==1: pass"
python timeit.py -s "x=1" "if x==2: pass"
python timeit.py -s "x=1" "if x: pass"
python timeit.py -s "x=100" "while x!=1: x-=1"
Potential future candidates:
GET_ITER predicts FOR_ITER
FOR_ITER predicts STORE_FAST or UNPACK_SEQUENCE
Also, applied missing goto fast_next_opcode to DUP_TOPX.
My previous patches should have used fast_next_opcode
in a few places instead of continue.
Also, applied one PyInt_AS_LONG macro in a place where
the type had already been checked.
rarely needed, but can sometimes be useful to release objects
referenced by the traceback held in sys.exc_info()[2]. (SF patch
#693195.) Thanks to Kevin Jacobs!
import warnings.py _after_ site.py has run. This ensures that site.py
is again the first .py to be imported, giving it back full control over
sys.path.
with an indented code block but no newline would raise SyntaxError.
This would have been a four-line change in parsetok.c... Except
codeop.py depends on this behavior, so a compilation flag had to be
invented that causes the tokenizer to revert to the old behavior;
this required extra changes to 2 .h files, 2 .c files, and 2 .py
files. (Fixes SF bug #501622.)
mostly from SF patch #683257, but I had to change unlock_import() to
return an error value to avoid fatal error.
Should this be backported? The patch requested this, but it's a new
feature.
"Unsigned" (i.e., positive-looking, but really negative) hex/oct
constants with a leading minus sign are once again properly negated.
The micro-optimization for negated numeric constants did the wrong
thing for such hex/oct constants. The patch avoids the optimization
for all hex/oct constants.
This needs to be backported to Python 2.2!
object is not a real str or unicode but an instance
of a subclass, construct the output via looping
over __getitem__. This guarantees that the result
is the same for function==None and function==lambda x:x
This doesn't happen for tuples, because filtertuple()
uses PyTuple_GetItem().
(This was discussed on SF bug #665835).
-DCALL_PROFILE: Count the number of function calls executed.
When this symbol is defined, the ceval mainloop and helper functions
count the number of function calls made. It keeps detailed statistics
about what kind of object was called and whether the call hit any of
the special fast paths in the code.
Optimization:
When we take the fast_function() path, which seems to be taken for
most function calls, and there is minimal frame setup to do, avoid
call PyEval_EvalCodeEx(). The eval code ex function does a lot of
work to handle keywords args and star args, free variables,
generators, etc. The inlined version simply allocates the frame and
copies the arguments values into the frame.
The optimization gets a little help from compile.c which adds a
CO_NOFREE flag to code objects that don't have free variables or cell
variables. This change allows fast_function() to get into the fast
path with fewer tests.
I measure a couple of percent speedup in pystone with this change, but
there's surely more that can be done.
blindly assumed that tp_as_sequence->sq_item always returns
a str or unicode object. This might fail with str or unicode
subclasses.
This patch checks whether the object returned from __getitem__
is a str/unicode object and raises a TypeError if not (and
the filter function returned true).
Furthermore the result for __getitem__ can be more than one
character long, so checks for enough memory have to be done.
__module__ is the string name of the module the function was defined
in, just like __module__ of classes. In some cases, particularly for
C functions, the __module__ may be None.
Change PyCFunction_New() from a function to a macro, but keep an
unused copy of the function around so that we don't change the binary
API.
Change pickle's save_global() to use whichmodule() if __module__ is
None, but add the __module__ logic to whichmodule() since it might be
used outside of pickle.
Make the code slightly shorter, faster, and easier to
read.
* Eliminate unused DUP_TOPX code for x==1.
compile.c always generates DUP_TOP instead.
* Since only two cases remain for DUP_TOPX, replace
the switch-case with if-elseif.
* The in-lined integer compare does a CheckExact on
both arguments. Since the second is a little more
likely to fail, test it first.
* The switch-case for IS/IS_NOT and IN/NOT_IN can
separate the regular and inverted cases with no
additional work. For all four paths, saves a test and
jump.
the AEDesc data shouldn't be disposed when the Python object is.
Added a C call AEDesc_NewBorrowed() to create these objects and a Python
method old=AEDesc.AutoDispose(onoff) to change auto-dispose state.
The two are semantically equivalent, but the first triggered a compiler
warning about an unused variable. Note, the preceding steps had already
accessed and decreffed the variable so the reference counts were fine.
parameter being either four or five. Currently, compile.c does not
generate calls with a parameter higher than three.
May have to be reverted if the second alpha or beta shakes out some
other tool generating this op code with a parameter of four or five.
Replaced groups of pushes and pops with indexed access to the stack and
a single adjustment (if needed) to the stacklevel.
Avoids scores of unnecessary increments and decrements to the stackpointer.
Removes unnecessary sequential dependencies so that the compiler has more
freedom for optimizations. Frees the processor for more parallel and
pipelined execution by using mostly read-only access and having few pointer
adjustments just prior to a read or write.
This fixes the problem on Windows - that's the only system where I can
test it.
It leaves sys.argv alone and only changes sys.path[0] to an absolute
pathname.
A variety of changes from Michael Hudson to get the compiler working
with 2.3. The primary change is the handling of SET_LINENO:
# The set_lineno() function and the explicit emit() calls for
# SET_LINENO below are only used to generate the line number table.
# As of Python 2.3, the interpreter does not have a SET_LINENO
# instruction. pyassem treats SET_LINENO opcodes as a special case.
A few other small changes:
- Remove unused code from pycodegen and pyassem.
- Fix error handling in parsermodule. When PyParser_SimplerParseString()
fails, it sets an exception with detailed info. The parsermodule
was clobbering that exception and replacing it was a generic
"could not parse string" exception. Keep the original exception.
I can't test this on the snake farm (no aix box is working).
This change works for the submitter seems correct.
Can anybody test this on 32- and 64- bit AIX?
Initialize the small integers and __builtins__ in startup.
This removes some if conditions.
Change XDECREF to DECREF for values which shouldn't be NULL.
- new import hooks in import.c, exposed in the sys module
- new module called 'zipimport'
- various changes to allow bootstrapping from zip files
I hope I didn't break the Windows build (or anything else for that
matter), but then again, it's been sitting on sf long enough...
Regarding the latest discussions on python-dev: zipimport sets
pkg.__path__ as specified in PEP 273, and likewise, sys.path item such as
/path/to/Archive.zip/subdir/ are supported again.
Obtain cleaner coding and a system wide
performance boost by using the fast, pre-parsed
PyArg_Unpack function instead of PyArg_ParseTuple
function which is driven by a format string.
Alex Martelli
Raymond Hettinger
Tim Peters
Mark Hammond
Martin v. Löwis
Guido van Rossum
Jack Jansen
Thomas Heller
Neal Norwitz
Gustavo Niemeyer
Fred Drake
Michael W. Hudson
Just van Rossum
Walter Dörwald
Marc-André Lemburg
Jeremy Hylton
Neil Schemenauer