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Re: RFC: GIMPLE tuples. Design and implementation proposal
- From: "J.C. Pizarro" <jcpiza at gmail dot com>
- To: "Diego Novillo" <dnovillo at redhat dot com>
- Cc: gcc at gcc dot gnu dot org
- Date: Tue, 10 Apr 2007 08:08:03 +0200
- Subject: Re: RFC: GIMPLE tuples. Design and implementation proposal
- References: <461B175A.1050407@redhat.com>
The "conditional jumps" are sometimes bad.
However, they've appeared the "conditional moves" to don't jump
and consecuently to reduce the penalization of the conditional jump.
I've the idea of combining GS_ASSIGN... and GS_COND... to give these
following 6 new GIMPLE instructions:
GS_ASSIGN_COND
GS_ASSIGN_COND_EQ
GS_ASSIGN_COND_NE
GS_ASSIGN_COPY_COND
GS_ASSIGN_COPY_COND_EQ
GS_ASSIGN_COPY_COND_NE
There are many good "cmovXX" from Intel i686.
Please, search the word "cmov" in this url
http://webster.cs.ucr.edu/AoA/Windows/PDFs/AppendixD.pdf
and you will discover new optimized ideas. You will need a good simplifying.
Good bye.
J.C. Pizarro :)