In Python 2.x, exceptions in finally blocks are not normalized. Since with
statements are implemented using finally blocks, ceval.c had to be tweaked to
distinguish between with finally blocks and normal ones.
A test for the finalization of generators containing with statements was also
added.
from a gcc inline assembler peculiarity. (gcc's "A" constraint
apparently means 'rax or rdx' in 64-bit mode, not edx:eax
or rdx:rax as one might expect.)
lnotab-based tracing is very complicated and isn't documented very well. There
were at least 3 comment blocks purporting to document co_lnotab, and none did a
very good job. This patch unifies them into Objects/lnotab_notes.txt which
tries to completely capture the current state of affairs.
I also discovered that we've attached 2 layers of patches to the basic tracing
scheme. The first layer avoids jumping to instructions that don't start a line,
to avoid problems in if statements and while loops. The second layer
discovered that jumps backward do need to trace at instructions that don't
start a line, so it added extra lnotab entries for 'while' and 'for' loops, and
added a special case for backward jumps within the same line. I replaced these
patches by just treating forward and backward jumps differently.
Most uses of PyCode_Addr2Line
(http://www.google.com/codesearch?q=PyCode_Addr2Line) are just trying to get
the line number of a specified frame, but there's no way to do that directly.
Forcing people to go through the code object makes them know more about the
guts of the interpreter than they should need.
The remaining uses of PyCode_Addr2Line seem to be getting the line from a
traceback (for example,
http://www.google.com/codesearch/p?hl=en#u_9_nDrchrw/pygame-1.7.1release/src/base.c&q=PyCode_Addr2Line),
which is replaced by the tb_lineno field. So we may be able to deprecate
PyCode_Addr2Line entirely for external use.
POP_JUMP_IF_{TRUE,FALSE} and JUMP_IF_{TRUE,FALSE}_OR_POP. This avoids executing
a POP_TOP on each conditional and sometimes allows the peephole optimizer to
skip a JUMP_ABSOLUTE entirely. It speeds up list comprehensions significantly.
Allows dictionaries to be pre-sized (upto 255 elements) saving time lost
to re-sizes with their attendant mallocs and re-insertions.
Has zero effect on small dictionaries (5 elements or fewer), a slight
benefit for dicts upto 22 elements (because they had to resize once
anyway), and more benefit for dicts upto 255 elements (saving multiple
resizes during the build-up and reducing the number of collisions on
the first insertions). Beyond 255 elements, there is no addional benefit.
Benjamin Peterson
Alexandre Vassalotti
Mark Dickinson
Antoine Pitrou
Jeffrey Yasskin
Collin Winter
Kristján Valur Jónsson
Amaury Forgeot d'Arc
Jesse Noller
Raymond Hettinger
Georg Brandl
Gregory P. Smith
Christian Heimes
Guido van Rossum
Nick Coghlan
Neal Norwitz