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Re: patch: convert scalar literals to vector constants (PR/7277)
- From: Aldy Hernandez <aldyh at redhat dot com>
- To: Richard Henderson <rth at redhat dot com>
- Cc: gcc-patches at gcc dot gnu dot org
- Date: Tue, 3 Jun 2003 17:38:54 -0400
- Subject: Re: patch: convert scalar literals to vector constants (PR/7277)
! cst[0] = INTVAL (x);
! cst[1] = 0;
CONST_INT sign-extends.
How about:?
if (INTVAL (x) < 0)
cst[1] = (unsigned HOST_WIDE_INT) -1;
Well, that works for integer vector modes. What about
fp vector modes? And how about
Hadn't thought of that. What do you suggest gets generated for this?:
typedef int v __attribute__((mode(V2SF)));
v null(void)
{
return (v) 0x1234LL;
}
Right now we are generating:
(const_vector:V2SF [
(const_int 0 [0x0])
(const_int 4660 [0x1234])
])
Which I'm not particularly fond of. Perhaps:?
(const_vector:V2SF [
(const_double 0 0)
(const_double 0 0x1234)
])
(v4sf)(v8hi)-1
where this routine should be called twice, the second
time to convert one vector mode to another?
Ok, I'm adding:
if (VECTOR_MODE_P (mode) && CONSTANT_P (x)
>>> && GET_CODE (x) != CONST_VECTOR
return convert_const_to_vector (mode, x);
...the code will drop through and convert_mode() below can handle
vector conversions.
Aldy