classification
Title: Better dead code elimination for the AST compiler
Type: Stage:
Components: Interpreter Core Versions: Python 2.5
process
Status: closed Resolution: accepted
Dependencies: Superseder:
Assigned To: georg.brandl Nosy List: brett.cannon, georg.brandl, nnorwitz, sdahlbac, titanstar (5)
Priority: normal Keywords: patch

Created on 2005-11-02 18:21 by titanstar, last changed 2006-06-04 21:57 by georg.brandl.

Files
File name Uploaded Description Edit Remove
if0.diff georg.brandl, 2006-05-26 11:34 new patch
Messages (7)
msg48946 - (view) Author: Rune Holm (titanstar) Date: 2005-11-02 18:21 
Here's a patch that adds dead code elimination for if
0: style statements, and improves the current dead code
elimination for while statements by not performing
elimination if the function is a generator.  If the
last yield statement from a generator is removed, the
generator is turned into a regular function, which
changes the semantics of the function.
msg48947 - (view) Author: Simon Dahlbacka (sdahlbac) Date: 2005-11-06 19:08 
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the actual patch is missing..
msg48948 - (view) Author: Rune Holm (titanstar) Date: 2005-11-06 20:41 
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Sorry, I'm new to the sourceforge patch tracker. The patch should be 
attached now.
msg48949 - (view) Author: Georg Brandl (georg.brandl) Date: 2006-05-26 11:34 
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Attaching new patch which does elimination for if 0, if 1
and if __debug__ correctly (visiting else clauses!) and
correctly recognizes functions mixing "return x" and "yield".
msg48950 - (view) Author: Brett Cannon (brett.cannon) Date: 2006-06-03 23:51 
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Replied on python-dev, but for thoroughness, the patch looks
fine from looking at the patch file itself.  Apply the
'return' detection on its own, though, for better tracking
of changes and easier rollback if something does go bad.
msg48951 - (view) Author: Neal Norwitz (nnorwitz) Date: 2006-06-04 06:07 
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It would be nice to make a #define for the error message so
they don't get out of sync.  I wouldn't mind seeing the
variable name spelled out, ste_returns_value or something
like that.

I didn't look closely at the line numbers and verify the
changes were correct.
msg48952 - (view) Author: Georg Brandl (georg.brandl) Date: 2006-06-04 21:57 
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Added your suggestions and committed as rev. 46650.
History
Date User Action Args
2005-11-02 18:21:32titanstarcreate