ref: b20a2d63f21ed0c26d0527fed3eba9b6035842d7
dir: /src/x86/msac.asm/
; Copyright © 2019, VideoLAN and dav1d authors
; Copyright © 2019, Two Orioles, LLC
; All rights reserved.
;
; Redistribution and use in source and binary forms, with or without
; modification, are permitted provided that the following conditions are met:
;
; 1. Redistributions of source code must retain the above copyright notice, this
; list of conditions and the following disclaimer.
;
; 2. Redistributions in binary form must reproduce the above copyright notice,
; this list of conditions and the following disclaimer in the documentation
; and/or other materials provided with the distribution.
;
; THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
; ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
; WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
; DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
; ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
; (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
; ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
; (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
; SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
%include "config.asm"
%include "ext/x86/x86inc.asm"
%if ARCH_X86_64
SECTION_RODATA 64 ; avoids cacheline splits
dw 60, 56, 52, 48, 44, 40, 36, 32, 28, 24, 20, 16, 12, 8, 4, 0
pw_0xff00: times 8 dw 0xff00
pw_32: times 8 dw 32
struc msac
.buf: resq 1
.end: resq 1
.dif: resq 1
.rng: resd 1
.cnt: resd 1
.update_cdf: resd 1
endstruc
%define m(x) mangle(private_prefix %+ _ %+ x %+ SUFFIX)
SECTION .text
%if WIN64
DECLARE_REG_TMP 3
%define buf rsp+8 ; shadow space
%else
DECLARE_REG_TMP 0
%define buf rsp-40 ; red zone
%endif
INIT_XMM sse2
cglobal msac_decode_symbol_adapt4, 3, 7, 6, s, cdf, ns
movd m2, [sq+msac.rng]
movq m1, [cdfq]
lea rax, [pw_0xff00]
movq m3, [sq+msac.dif]
mov r3d, [sq+msac.update_cdf]
mov r4d, nsd
neg nsq
pshuflw m2, m2, q0000
movd [buf+12], m2
pand m2, [rax]
mova m0, m1
psrlw m1, 6
psllw m1, 7
pmulhuw m1, m2
movq m2, [rax+nsq*2]
pshuflw m3, m3, q3333
paddw m1, m2
mova [buf+16], m1
psubusw m1, m3
pxor m2, m2
pcmpeqw m1, m2 ; c >= v
pmovmskb eax, m1
test r3d, r3d
jz .renorm ; !allow_update_cdf
; update_cdf:
movzx r3d, word [cdfq+r4*2] ; count
pcmpeqw m2, m2
mov r2d, r3d
shr r3d, 4
cmp r4d, 4
sbb r3d, -5 ; (count >> 4) + (n_symbols > 3) + 4
cmp r2d, 32
adc r2d, 0 ; count + (count < 32)
movd m3, r3d
pavgw m2, m1 ; i >= val ? -1 : 32768
psubw m2, m0 ; for (i = 0; i < val; i++)
psubw m0, m1 ; cdf[i] += (32768 - cdf[i]) >> rate;
psraw m2, m3 ; for (; i < n_symbols - 1; i++)
paddw m0, m2 ; cdf[i] += (( -1 - cdf[i]) >> rate) + 1;
movq [cdfq], m0
mov [cdfq+r4*2], r2w
.renorm:
tzcnt eax, eax
mov r4, [sq+msac.dif]
movzx r1d, word [buf+rax+16] ; v
movzx r2d, word [buf+rax+14] ; u
shr eax, 1
.renorm2:
not r4
sub r2d, r1d ; rng
shl r1, 48
add r4, r1 ; ~dif
.renorm3:
mov r1d, [sq+msac.cnt]
movifnidn t0, sq
bsr ecx, r2d
xor ecx, 15 ; d
shl r2d, cl
shl r4, cl
mov [t0+msac.rng], r2d
not r4
sub r1d, ecx
jge .end ; no refill required
; refill:
mov r2, [t0+msac.buf]
mov rcx, [t0+msac.end]
lea r5, [r2+8]
cmp r5, rcx
jg .refill_eob
mov r2, [r2]
lea ecx, [r1+23]
add r1d, 16
shr ecx, 3 ; shift_bytes
bswap r2
sub r5, rcx
shl ecx, 3 ; shift_bits
shr r2, cl
sub ecx, r1d ; shift_bits - 16 - cnt
mov r1d, 48
shl r2, cl
mov [t0+msac.buf], r5
sub r1d, ecx ; cnt + 64 - shift_bits
xor r4, r2
.end:
mov [t0+msac.cnt], r1d
mov [t0+msac.dif], r4
RET
.refill_eob: ; avoid overreading the input buffer
mov r5, rcx
mov ecx, 40
sub ecx, r1d ; c
.refill_eob_loop:
cmp r2, r5
jge .refill_eob_end ; eob reached
movzx r1d, byte [r2]
inc r2
shl r1, cl
xor r4, r1
sub ecx, 8
jge .refill_eob_loop
.refill_eob_end:
mov r1d, 40
sub r1d, ecx
mov [t0+msac.buf], r2
mov [t0+msac.dif], r4
mov [t0+msac.cnt], r1d
RET
cglobal msac_decode_symbol_adapt8, 3, 7, 6, s, cdf, ns
movd m2, [sq+msac.rng]
movu m1, [cdfq]
lea rax, [pw_0xff00]
movq m3, [sq+msac.dif]
mov r3d, [sq+msac.update_cdf]
mov r4d, nsd
neg nsq
pshuflw m2, m2, q0000
movd [buf+12], m2
punpcklqdq m2, m2
mova m0, m1
psrlw m1, 6
pand m2, [rax]
psllw m1, 7
pmulhuw m1, m2
movu m2, [rax+nsq*2]
pshuflw m3, m3, q3333
paddw m1, m2
punpcklqdq m3, m3
mova [buf+16], m1
psubusw m1, m3
pxor m2, m2
pcmpeqw m1, m2
pmovmskb eax, m1
test r3d, r3d
jz m(msac_decode_symbol_adapt4).renorm
movzx r3d, word [cdfq+r4*2]
pcmpeqw m2, m2
mov r2d, r3d
shr r3d, 4
cmp r4d, 4 ; may be called with n_symbols < 4
sbb r3d, -5
cmp r2d, 32
adc r2d, 0
movd m3, r3d
pavgw m2, m1
psubw m2, m0
psubw m0, m1
psraw m2, m3
paddw m0, m2
movu [cdfq], m0
mov [cdfq+r4*2], r2w
jmp m(msac_decode_symbol_adapt4).renorm
cglobal msac_decode_symbol_adapt16, 3, 7, 6, s, cdf, ns
movd m4, [sq+msac.rng]
movu m2, [cdfq]
lea rax, [pw_0xff00]
movu m3, [cdfq+16]
movq m5, [sq+msac.dif]
mov r3d, [sq+msac.update_cdf]
mov r4d, nsd
neg nsq
%if WIN64
sub rsp, 48 ; need 36 bytes, shadow space is only 32
%endif
pshuflw m4, m4, q0000
movd [buf-4], m4
punpcklqdq m4, m4
mova m0, m2
psrlw m2, 6
mova m1, m3
psrlw m3, 6
pand m4, [rax]
psllw m2, 7
psllw m3, 7
pmulhuw m2, m4
pmulhuw m3, m4
movu m4, [rax+nsq*2]
pshuflw m5, m5, q3333
paddw m2, m4
psubw m4, [rax-pw_0xff00+pw_32]
punpcklqdq m5, m5
paddw m3, m4
mova [buf], m2
mova [buf+16], m3
psubusw m2, m5
psubusw m3, m5
pxor m4, m4
pcmpeqw m2, m4
pcmpeqw m3, m4
packsswb m5, m2, m3
pmovmskb eax, m5
test r3d, r3d
jz .renorm
movzx r3d, word [cdfq+r4*2]
pcmpeqw m4, m4
mova m5, m4
lea r2d, [r3+80] ; only support n_symbols >= 4
shr r2d, 4
cmp r3d, 32
adc r3d, 0
pavgw m4, m2
pavgw m5, m3
psubw m4, m0
psubw m0, m2
movd m2, r2d
psubw m5, m1
psubw m1, m3
psraw m4, m2
psraw m5, m2
paddw m0, m4
paddw m1, m5
movu [cdfq], m0
movu [cdfq+16], m1
mov [cdfq+r4*2], r3w
.renorm:
tzcnt eax, eax
mov r4, [sq+msac.dif]
movzx r1d, word [buf+rax*2]
movzx r2d, word [buf+rax*2-2]
%if WIN64
add rsp, 48
%endif
jmp m(msac_decode_symbol_adapt4).renorm2
cglobal msac_decode_bool_equi, 1, 7, 0, s
mov r1d, [sq+msac.rng]
mov r4, [sq+msac.dif]
mov r2d, r1d
mov r1b, 8
mov r3, r4
mov eax, r1d
shr r1d, 1 ; v
shl rax, 47 ; vw
sub r2d, r1d ; r - v
sub r4, rax ; dif - vw
cmovb r2d, r1d
cmovb r4, r3
setb al ; the upper 32 bits contains garbage but that's OK
not r4
jmp m(msac_decode_symbol_adapt4).renorm3
%endif