x86 SSE constants

[Jan Hubicka]

> On Fri, Sep 30, 2005 at 04:31:59PM -0700, Dale Johannesen wrote:
> > No, there isn't, but it might be a smaller change to add a new 
> > constraint....
> > having constraints tied to specific constants is pretty ugly, and so is
> > having (if (constant value==0)) in a lot of patterns..,,
> 
> That's why you'd centralize this into a few functions.  There
> are several things that need changing:
> 
>   * Match different forms of constant for C.
> 
>   * Update vector_move_operand to use that same routine.
> 
>   * A routine to determine which of several instructions
>     we want to emit.  E.g. xorps instead of pxor for -Os.
>     It should return a ATTR_MODE result so that we can 
>     call it from the mode attribute of various instructions.
> 
>   * A routine that uses the previous to return a const char*
>     template to return from the insn output patterns.
> 
> For bonus points, handle MMX too.

Yep. It seems to me that current way
standard_80387_constant_p/standard_80387_constant_opcode and 'G'
constraint is handled is pretty much symetrical problem (and it is dealt
with quite resonably), so we should have same approaches in both cases.

Honza
> 
> 
> r~