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* [Bug middle-end/33349] Redundant zero-extension of registers
[not found] <bug-33349-4@http.gcc.gnu.org/bugzilla/>
@ 2011-06-16 11:28 ` gcc.hall at gmail dot com
0 siblings, 0 replies; 2+ messages in thread
From: gcc.hall at gmail dot com @ 2011-06-16 11:28 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33349
Jeremy <gcc.hall at gmail dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |gcc.hall at gmail dot com
--- Comment #2 from Jeremy <gcc.hall at gmail dot com> 2011-06-16 11:27:24 UTC ---
Another example I came across ...
unsigned short sw;
asm( "fnstsw %0" : "=a" (sw) );
if( sw & FE_DIVBYZERO )
...
if( sw & FE_OVERFLOW )
...
if( sw & FE_UNDERFLOW )
...
generates:
movzx eax, ax # D.14460, sw
test al, 1 # D.14460,
test al, 4 # D.14460,
test al, 8 # D.14460,
^ permalink raw reply [flat|nested] 2+ messages in thread
* [Bug middle-end/33349] Redundant zero-extension of registers
2007-09-08 3:07 [Bug c++/33349] New: " us15 at os dot inf dot tu-dresden dot de
@ 2009-02-06 21:45 ` steven at gcc dot gnu dot org
0 siblings, 0 replies; 2+ messages in thread
From: steven at gcc dot gnu dot org @ 2009-02-06 21:45 UTC (permalink / raw)
To: gcc-bugs
------- Comment #1 from steven at gcc dot gnu dot org 2009-02-06 21:45 -------
This would be fixed if someone would fix the Sign Extension Elimination pass
(yes, it also handles zero extensions). But that pass is probably broken
beyond repair at this point, and likely needs a rewrite instead of just a fix.
--
steven at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Ever Confirmed|0 |1
Last reconfirmed|0000-00-00 00:00:00 |2009-02-06 21:45:16
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33349
^ permalink raw reply [flat|nested] 2+ messages in thread
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[not found] <bug-33349-4@http.gcc.gnu.org/bugzilla/>
2011-06-16 11:28 ` [Bug middle-end/33349] Redundant zero-extension of registers gcc.hall at gmail dot com
2007-09-08 3:07 [Bug c++/33349] New: " us15 at os dot inf dot tu-dresden dot de
2009-02-06 21:45 ` [Bug middle-end/33349] " steven at gcc dot gnu dot org
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