This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: Suboptimal code generation if if - conversion
- From: Richard Henderson <rth at redhat dot com>
- To: Hartmut Penner <HPENNER at de dot ibm dot com>
- Cc: gcc-patches at gcc dot gnu dot org
- Date: Fri, 25 Oct 2002 13:54:00 -0700
- Subject: Re: Suboptimal code generation if if - conversion
- References: <OF877EE999.69F0E3F4-ONC1256C4E.00252978@de.ibm.com>
On Thu, Oct 10, 2002 at 09:00:18AM +0200, Hartmut Penner wrote:
> But a short remark to ifcvt, if the cfg cleanup routines does not
> convert the jump, ifcvt will do it, if and only if the test is
> done against a register, that the problem I saw.
> But since with a right way of writing code, cfg will do the
> optimization, I guess it is not worth thinking about a fix.
You're right.
It probably is worthwhile to make modified_in_p not automatically
return true for memories. At minimum it should check to see that
_some_ memory is modified in the insn; at best it could note when
init_alias_analysis is active and test vs that.
r~