UNSPEC vs. CLOBBER followed by (set (subreg ...))

[Richard Henderson]

On Mon, Jan 24, 2000 at 12:38:39PM -0800, Geoff Keating wrote:
> I don't believe that a CLOBBER followed by (set (subreg ...)) will be
> optimized worse than an UNSPEC...

In fact I believe the opposite to be true.  You should get better
code from the unspec than the subreg.

> (insn 24 22 26 (set (mem:DI (plus:SI (reg:SI 31 r31)
>                 (const_int 8 [0x8])) 0)
>         (reg:DI 84)) 442 {*movdi_32} (insn_list 22 (nil))

I thought you didn't allow DImode values in the FP regs?


r~