cosmopolitan/dsp/tty/windex-avx2.S

73 lines
2.9 KiB
ArmAsm

/*-*- mode:unix-assembly; indent-tabs-mode:t; tab-width:8; coding:utf-8 -*-│
vi: set et ft=asm ts=8 tw=8 fenc=utf-8 :vi
Copyright 2020 Justine Alexandra Roberts Tunney
This program is free software; you can redistribute it and/or modify │
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License. │
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of │
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software │
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA
*/
#include "libc/macros.h"
.source __FILE__
/ Returns index of minimum uint16 in array.
/
/ @param rdi points to nonempty array
/ @param rsi is item count divisible by 16
/ @note needs avx2 (haswell+)
windex$avx2:
push %rbp
mov %rsp,%rbp
.profilable
and $-32,%rsp
sub $32,%rsp
vmovdqa (%rdi),%ymm1
vmovdqa .Lidx(%rip),%ymm3
vmovdqa .Linc(%rip),%ymm5
cmp $16,%esi
jbe 2f
vmovdqa %ymm3,%ymm0
mov $16,%eax
3: vpaddw %ymm0,%ymm5,%ymm0
mov %eax,%edx
vmovdqa (%rdi,%rdx,2),%ymm2
vpcmpgtw %ymm2,%ymm1,%ymm4
vpblendvb %ymm4,%ymm0,%ymm3,%ymm3
vpminsw %ymm1,%ymm2,%ymm1
add $16,%eax
cmp %eax,%esi
ja 3b
2: vphminposuw %xmm1,%xmm0
vextracti128 $0x1,%ymm1,%xmm1
vphminposuw %xmm1,%xmm1
vmovdqa %ymm3,(%rsp)
vmovq %xmm0,%rdx
vmovq %xmm1,%rax
cmp %dx,%ax
jbe 4f
sar $16,%rdx
movzwl %dx,%edx
movzwl (%rsp,%rdx,2),%eax
jmp 5f
4: sar $16,%rax
movzwl %ax,%eax
movzwl 16(%rsp,%rax,2),%eax
5: vzeroupper
leave
ret
.endfn windex$avx2,globl
.rodata.cst32
.Lidx: .short 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15
.Linc: .value 16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16