Re: GCC no longer synthesizing v2sf operations from v4sf operations?

[Uros Bizjak]

Hello!
typedef float v4sf __attribute__((vector_size(16)));
void foo(v4sf *a, v4sf *b, v4sf *c)
{
       *a = *b + *c;
}
we no longer (since 4.0) synthesize v2sf (aka sse) operations
for f.i. -march=athlon (not that we were too successful at this
in 3.4 - we generated horrible code instead).  Instead for !sse2
architectures we generate standard i387 FP code (with some
unnecessary temporaries, but reasonably well).
 

SSE _is_ v4sf. 'gcc -O2 -msse -S -fomit-frame-pointer' produces:
foo:
       movl    12(%esp), %eax
       movaps  (%eax), %xmm0
       movl    8(%esp), %eax
       addps   (%eax), %xmm0
       movl    4(%esp), %eax
       movaps  %xmm0, (%eax)
       ret
SSE2 is v2df.
Athlon does not handle SSE insns.
Uros.