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* [Bug target/29775] redundant movzbl
[not found] <bug-29775-4@http.gcc.gnu.org/bugzilla/>
@ 2012-01-28 2:53 ` pinskia at gcc dot gnu.org
0 siblings, 0 replies; 2+ messages in thread
From: pinskia at gcc dot gnu.org @ 2012-01-28 2:53 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29775
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> 2012-01-28 02:20:32 UTC ---
I think this is a dup of bug 29776.
^ permalink raw reply [flat|nested] 2+ messages in thread
* [Bug target/29775] redundant movzbl
2006-11-09 7:03 [Bug target/29775] New: " dean at arctic dot org
@ 2007-02-03 4:49 ` michael dot meissner at amd dot com
0 siblings, 0 replies; 2+ messages in thread
From: michael dot meissner at amd dot com @ 2007-02-03 4:49 UTC (permalink / raw)
To: gcc-bugs
------- Comment #1 from michael dot meissner at amd dot com 2007-02-03 04:49 -------
If you look at the RTL, in the if statement, the RTL loads the QI value into
the register and does the test against the QI value, and the movzbl is how the
load is done. The second movzbl is to zero extend the value into a SI value
that can be used in the __builtin_ctz function.
In addition, there is a spurious move at the end to move the value from %edx
into %eax for the return.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29775
^ permalink raw reply [flat|nested] 2+ messages in thread
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[not found] <bug-29775-4@http.gcc.gnu.org/bugzilla/>
2012-01-28 2:53 ` [Bug target/29775] redundant movzbl pinskia at gcc dot gnu.org
2006-11-09 7:03 [Bug target/29775] New: " dean at arctic dot org
2007-02-03 4:49 ` [Bug target/29775] " michael dot meissner at amd dot com
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