Message 63063 - Python tracker

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Author	belopolsky
Recipients	belopolsky
Date	2008-02-27.04:42:35
SpamBayes Score	0.14607638
Marked as misclassified	No
Message-id	<[email protected]>
In-reply-to

Content
I am attaching a proof-of-concept patch that changes the bytecode generated from {1:1,2:2,3:3,4:4} from BUILD_MAP 4 LOAD_CONST 2 (1) LOAD_CONST 2 (1) STORE_MAP LOAD_CONST 1 (2) LOAD_CONST 1 (2) STORE_MAP LOAD_CONST 4 (3) LOAD_CONST 4 (3) STORE_MAP LOAD_CONST 3 (4) LOAD_CONST 3 (4) STORE_MAP to LOAD_CONST 1 (4) LOAD_CONST 1 (4) LOAD_CONST 2 (3) LOAD_CONST 2 (3) LOAD_CONST 3 (2) LOAD_CONST 3 (2) LOAD_CONST 4 (1) LOAD_CONST 4 (1) BUILD_MAP 4 and changes BUILD_MAP to behave similarly to BUILD_(SET\|LIST\|TUPLE) and consume 2n items from the stack. The advantage is more compact and faster bytecode and uniform treatment of BUILD_ instructions.

I am attaching a proof-of-concept patch that changes the bytecode 
generated from {1:1,2:2,3:3,4:4} from 

BUILD_MAP                4  
LOAD_CONST               2 (1)  
LOAD_CONST               2 (1)  
STORE_MAP             
LOAD_CONST               1 (2)  
LOAD_CONST               1 (2)  
STORE_MAP             
LOAD_CONST               4 (3)  
LOAD_CONST               4 (3)  
STORE_MAP             
LOAD_CONST               3 (4)  
LOAD_CONST               3 (4)  
STORE_MAP             

to

LOAD_CONST               1 (4)  
LOAD_CONST               1 (4)  
LOAD_CONST               2 (3)   
LOAD_CONST               2 (3)                                                    
LOAD_CONST               3 (2)                                        
LOAD_CONST               3 (2)                                         
LOAD_CONST               4 (1)  
LOAD_CONST               4 (1)  
BUILD_MAP                4  
 
and changes BUILD_MAP to behave similarly to BUILD_(SET|LIST|TUPLE) and 
consume 2*n items from the stack.

The advantage is more compact and faster bytecode and uniform treatment 
of BUILD_* instructions.

History
Date	User	Action	Args
2008-02-27 04:42:38	belopolsky	set	spambayes_score: 0.146076 -> 0.14607638 recipients: + belopolsky
2008-02-27 04:42:38	belopolsky	set	spambayes_score: 0.146076 -> 0.146076 messageid: <[email protected]>
2008-02-27 04:42:37	belopolsky	link	issue2197 messages
2008-02-27 04:42:36	belopolsky	create