https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82426
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Ever confirmed|0 |1
Status|UNCONFIRMED |NEW
Severity|normal |enhancement
Last reconfirmed| |2021-08-25
--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Hmm, on aarch64 we do a decent job at vectorizing this (since GCC 11):
ldp d4, d0, [x1]
ldr d7, [x0, 16]
ldp d6, d5, [x0]
fmul v3.2s, v0.2s, v7.s[1]
ldr d1, [x1, 16]
fmul v2.2s, v0.2s, v6.s[1]
fmul v0.2s, v0.2s, v5.s[1]
fmla v3.2s, v4.2s, v7.s[0]
fmla v2.2s, v4.2s, v6.s[0]
fmla v0.2s, v4.2s, v5.s[0]
fadd v1.2s, v1.2s, v3.2s
stp d2, d0, [x8]
str d1, [x8, 16]
I suspect this is because V2SF does not exist on x86_64.
Using -Dfloat=double seems to get better for x86_64 (with -mavx2):
vmovupd (%rdx), %ymm0
vpermilpd $0, (%rsi), %ymm1
movq %rdi, %rax
vmovsd 32(%rsi), %xmm5
vmovsd 40(%rsi), %xmm4
vpermpd $68, %ymm0, %ymm2
vpermpd $238, %ymm0, %ymm3
vmulpd %ymm2, %ymm1, %ymm2
vpermilpd $15, (%rsi), %ymm1
vmulpd %ymm3, %ymm1, %ymm1
vaddpd %ymm1, %ymm2, %ymm1
vmulsd %xmm5, %xmm0, %xmm2
vmovupd %ymm1, (%rdi)
vmovapd %xmm0, %xmm1
vextractf128 $0x1, %ymm0, %xmm0
vmulsd %xmm4, %xmm0, %xmm3
vunpckhpd %xmm1, %xmm1, %xmm1
vunpckhpd %xmm0, %xmm0, %xmm0
vmulsd %xmm5, %xmm1, %xmm1
vmulsd %xmm4, %xmm0, %xmm0
vaddsd %xmm3, %xmm2, %xmm2
vaddsd 32(%rdx), %xmm2, %xmm2
vaddsd %xmm0, %xmm1, %xmm1
vaddsd 40(%rdx), %xmm1, %xmm1
vmovsd %xmm2, 32(%rdi)
vmovsd %xmm1, 40(%rdi)
