[Python-checkins] python/dist/src/Misc NEWS,1.737,1.738

2003年4月21日 23:49:11 -0700

Update of /cvsroot/python/python/dist/src/Misc
In directory sc8-pr-cvs1:/tmp/cvs-serv4294/Misc
Modified Files:
	NEWS 
Log Message:
Improved the bytecode optimizer.
* 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.
Index: NEWS
===================================================================
RCS file: /cvsroot/python/python/dist/src/Misc/NEWS,v
retrieving revision 1.737
retrieving revision 1.738
diff -C2 -d -r1.737 -r1.738
*** NEWS	19 Apr 2003 20:59:03 -0000	1.737
--- NEWS	22 Apr 2003 06:49:08 -0000	1.738
***************
*** 295,298 ****
--- 295,305 ----
 will be backported to Python 2.2.3 a well. (SF #660455)
 
+ - Added several bytecode optimizations. Provides speed-ups to
+ inverted in/is tests, inverted jumps, while 1 loops, and jumps to
+ unconditional jumps.
+ 
+ - Added a new opcode, NOP, which is used in some of the bytecode
+ transformations.
+ 
 - int(s, base) sometimes sign-folds hex and oct constants; it only
 does this when base is 0 and s.strip() starts with a '0'. When the