[Bug tree-optimization/15089] [3.4/3.5 Regression] [tree-ssa] local register variable with a specified register is bad

["mark at codesourcery dot com" <gcc-bugzilla at gcc dot gnu dot org>]

------- Additional Comments From mark at codesourcery dot com  2004-06-23 22:08 -------
Subject: Re:  [3.4/3.5 Regression] [tree-ssa]
 local register variable with a specified register is bad

Ian Lance Taylor wrote:

> "mmitchel at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org> writes:
> 
> 
>>When __l is used in the asm, the writer of the bugzilla report expects
>>to see register "r0".  However, the value happens to be hanging around
>>in a different register so GCC uses that other register instead of
>>"r0".  Similarly for uses of __i.   The behavior of the compiler is
>>precisely what I would expect."
> 
> 
> But what about this comment from RTH?
>     http://gcc.gnu.org/ml/gcc/2004-05/msg00657.html
> 
> He is describing what appears to me to be an undocumented feature, but
> one which he says is important.

I don't know; I don't have enough experience with these kinds of tricks. 
  (When I need to do these kinds of things, I just write assembly code.)

If Richard and Jeff agree to reopen the bug, that's fine with me.



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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15089