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[Bug rtl-optimization/21970] [3.4 only] Inline keyword causes computation to erroneously reduce to a constant
- From: "rsandifo at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: 5 Jul 2005 14:51:45 -0000
- Subject: [Bug rtl-optimization/21970] [3.4 only] Inline keyword causes computation to erroneously reduce to a constant
- References: <20050608225942.21970.para@cfl.rr.com>
- Reply-to: gcc-bugzilla at gcc dot gnu dot org
------- Additional Comments From rsandifo at gcc dot gnu dot org 2005-07-05 14:51 -------
> The analysis is slightly flawed. For example:
>
> UINT32 r0045025C = opt_and(ic, r004501D4); // N = and (_, M) :00022108
> UINT32 r00450994 = opt_not(r0045025C); // b = not (N) :fffddef7
>
> Since you are using 1s to represent bits that are known to be 0 and 0s
> to represent bits whose value are completely unknown, b should be
> 00000000. All known 0s flip to 1s, and you can say nothing about the
> other bits because their values are all unknown.
Yup. I guess you didn't read comment #4 ;)
Anyway, thanks for the confirmation. I'll close this as invalid.
--
What |Removed |Added
----------------------------------------------------------------------------
Status|WAITING |RESOLVED
Resolution| |INVALID
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21970