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* [Bug target/31028]  New: Microoptimization of the i386 and x86_64 compilers
@ 2007-03-02 16:53 michael dot meissner at amd dot com
  2007-03-02 17:45 ` [Bug target/31028] " ubizjak at gmail dot com
  0 siblings, 1 reply; 2+ messages in thread
From: michael dot meissner at amd dot com @ 2007-03-02 16:53 UTC (permalink / raw)
  To: gcc-bugs

There are a lot of feature test macros in the i386/x86_64 compiler of the form:
(x86_some_var & (1 << ix86_arch))

These tests could be micro-optimized, either by storing 1 << ix86_arch into a
global variable, or by having a global variable that is the result of the and
and the shift, so that a simple != 0 can be done.


-- 
           Summary: Microoptimization of the i386 and x86_64 compilers
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P3
         Component: target
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: michael dot meissner at amd dot com
 GCC build triplet: x86_64-pc-gnu-linux
  GCC host triplet: x86_64-pc-gnu-linux
GCC target triplet: x86_64-pc-gnu-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31028


^ permalink raw reply	[flat|nested] 2+ messages in thread
* [Bug target/31028] Microoptimization of the i386 and x86_64 compilers
  2007-03-02 16:53 [Bug target/31028] New: Microoptimization of the i386 and x86_64 compilers michael dot meissner at amd dot com
@ 2007-03-02 17:45 ` ubizjak at gmail dot com
  0 siblings, 0 replies; 2+ messages in thread
From: ubizjak at gmail dot com @ 2007-03-02 17:45 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #1 from ubizjak at gmail dot com  2007-03-02 17:45 -------


*** This bug has been marked as a duplicate of 31019 ***


-- 

ubizjak at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |DUPLICATE


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31028


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2007-03-02 16:53 [Bug target/31028] New: Microoptimization of the i386 and x86_64 compilers michael dot meissner at amd dot com
2007-03-02 17:45 ` [Bug target/31028] " ubizjak at gmail dot com

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