This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: [tree-ssa] Temporary Expression Replacement in SSA->normal.
- From: kenner at vlsi1 dot ultra dot nyu dot edu (Richard Kenner)
- To: zack at codesourcery dot com
- Cc: gcc-patches at gcc dot gnu dot org
- Date: Fri, 12 Dec 03 21:01:32 EST
- Subject: Re: [tree-ssa] Temporary Expression Replacement in SSA->normal.
> int y = 3;
> return x*y;
there's nothing stopping the transformation to
T.1 = x << 1;
T.2 = T.1 + x;
return T.2;
from happening at the tree level.
Sure there is: it may not be faster on the target. It's not hard to
envision a processor that has a single-cyle multiply instruction.
Code choice decisions like this belong in the code generation part of
the compiler.