[Bug middle-end/84067] [8 regression] gcc.dg/wmul-1.c regression on aarch64 after r257077

[ktkachov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84067

--- Comment #4 from ktkachov at gcc dot gnu.org ---
(In reply to ktkachov from comment #3)
> (In reply to Richard Biener from comment #2)
> > So any hint on whether the code after r257077 is better or worse than before?
> 
> Looks worse unfortunately:
> For aarch64 at -O2 it generates:
> foo:
> 	mov	w3, 44
> 	mov	w2, 40
> 	mov	w5, 1
> 	mov	w4, 2
> 	smull	x3, w1, w3
> 	smull	x2, w1, w2
> 	str	w5, [x0, x3]
> 	add	x2, x2, 400
> 	add	x1, x2, x1, sxtw 2
> 	str	w4, [x0, x1]
> 	ret
> 
> whereas with r257077 it generates the shorter:

Sorry, I meant to write "with r257077 reverted..."

> foo:
> 	mov	w3, 40
> 	sxtw	x2, w1
> 	mov	w4, 1
> 	smaddl	x0, w1, w3, x0
> 	mov	w3, 2
> 	add	x1, x0, x2, lsl 2
> 	str	w4, [x0, x2, lsl 2]
> 	str	w3, [x1, 400]
> 	ret