cosmopolitan/dsp/tty/windex-sse4.S

62 lines
2.6 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
Permission to use, copy, modify, and/or distribute this software for
any purpose with or without fee is hereby granted, provided that the
above copyright notice and this permission notice appear in all copies.
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
PERFORMANCE OF THIS SOFTWARE.
*/
#include "libc/macros.h"
.source __FILE__
/ Returns index of minimum positive int16 in array.
/
/ @param rdi points to nonempty array
/ @param esi is 16-byte aligned 8+ / 8 multiple array item count
/ @note needs sse4 (nehalem+)
windex$sse4:
push %rbp
mov %rsp,%rbp
.profilable
mov $8,%eax
sub $32,%rsp
movdqa (%rdi),%xmm2
movdqa .Lidx(%rip),%xmm1
movdqa .Linc(%rip),%xmm6
movdqa %xmm1,%xmm3
0: cmp %eax,%esi
je 1f
add $8,%eax
movdqa -16(%rdi,%rax,2),%xmm4
movdqa %xmm2,%xmm7
movdqa %xmm3,%xmm5
paddw %xmm6,%xmm5
movdqa %xmm5,%xmm3
pcmpgtw %xmm4,%xmm7
pminsw %xmm4,%xmm2
movdqa %xmm7,%xmm0
pblendvb %xmm0,%xmm5,%xmm1
jmp 0b
1: phminposuw %xmm2,%xmm0
movd %xmm0,%eax
movdqa %xmm1,-32(%rbp)
shr $16,%eax
movzwl -32(%rbp,%rax,2),%eax
leave
ret
.endfn windex$sse4,globl
.rodata.cst16
.Lidx: .short 0,1,2,3,4,5,6,7
.Linc: .value 8,8,8,8,8,8,8,8