FFmpeg4/libavcodec/x86/celt_pvq_search.asm

386 lines
12 KiB
NASM

;******************************************************************************
;* SIMD optimized Opus encoder DSP function
;*
;* Copyright (C) 2017 Ivan Kalvachev <ikalvachev@gmail.com>
;*
;* This file is part of FFmpeg.
;*
;* FFmpeg is free software; you can redistribute it and/or
;* modify it under the terms of the GNU Lesser General Public
;* License as published by the Free Software Foundation; either
;* version 2.1 of the License, or (at your option) any later version.
;*
;* FFmpeg 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
;* Lesser General Public License for more details.
;*
;* You should have received a copy of the GNU Lesser General Public
;* License along with FFmpeg; if not, write to the Free Software
;* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
;******************************************************************************
%include "config.asm"
%include "libavutil/x86/x86util.asm"
%ifdef __NASM_VER__
%use "smartalign"
ALIGNMODE p6
%endif
SECTION_RODATA 64
const_float_abs_mask: times 8 dd 0x7fffffff
const_align_abs_edge: times 8 dd 0
const_float_0_5: times 8 dd 0.5
const_float_1: times 8 dd 1.0
const_float_sign_mask: times 8 dd 0x80000000
const_int32_offsets:
%rep 8
dd $-const_int32_offsets
%endrep
SECTION .text
;
; Setup High Register to be used
; for holding memory constants
;
; %1 - the register to be used, assmues it is >= mm8
; %2 - name of the constant.
;
; Subsequent opcodes are going to use the constant in the form
; "addps m0, mm_const_name" and it would be turned into:
; "addps m0, [const_name]" on 32 bit arch or
; "addps m0, m8" on 64 bit arch
%macro SET_HI_REG_MM_CONSTANT 3 ; movop, reg, const_name
%if num_mmregs > 8
%define mm_%3 %2
%{1} %2, [%3] ; movaps m8, [const_name]
%else
%define mm_%3 [%3]
%endif
%endmacro
;
; Set Position Independent Code
; Base address of a constant
; %1 - the register to be used, if PIC is set
; %2 - name of the constant.
;
; Subsequent opcode are going to use the base address in the form
; "movaps m0, [pic_base_constant_name+r4]" and it would be turned into
; "movaps m0, [r5 + r4]" if PIC is enabled
; "movaps m0, [constant_name + r4]" if texrel are used
%macro SET_PIC_BASE 3; reg, const_label
%ifdef PIC
%{1} %2, [%3] ; lea r5, [rip+const]
%define pic_base_%3 %2
%else
%define pic_base_%3 %3
%endif
%endmacro
%macro PULSES_SEARCH 1
; m6 Syy_norm
; m7 Sxy_norm
addps m6, mm_const_float_0_5 ; Syy_norm += 1.0/2
pxor m1, m1 ; max_idx
xorps m3, m3 ; p_max
xor r4d, r4d
align 16
%%distortion_search:
movd xm2, dword r4d ; movd zero extends
%ifidn %1,add
movaps m4, [tmpY + r4] ; y[i]
movaps m5, [tmpX + r4] ; X[i]
%if USE_APPROXIMATION == 1
xorps m0, m0
cmpps m0, m0, m5, 4 ; m0 = (X[i] != 0.0)
%endif
addps m4, m6 ; m4 = Syy_new = y[i] + Syy_norm
addps m5, m7 ; m5 = Sxy_new = X[i] + Sxy_norm
%if USE_APPROXIMATION == 1
andps m5, m0 ; if(X[i] == 0) Sxy_new = 0; Prevent aproximation error from setting pulses in array padding.
%endif
%else
movaps m5, [tmpY + r4] ; m5 = y[i]
xorps m0, m0 ; m0 = 0;
cmpps m0, m0, m5, 1 ; m0 = (0<y)
subps m4, m6, m5 ; m4 = Syy_new = Syy_norm - y[i]
subps m5, m7, [tmpX + r4] ; m5 = Sxy_new = Sxy_norm - X[i]
andps m5, m0 ; (0<y)?m5:0
%endif
%if USE_APPROXIMATION == 1
rsqrtps m4, m4
mulps m5, m4 ; m5 = p = Sxy_new*approx(1/sqrt(Syy) )
%else
mulps m5, m5
divps m5, m4 ; m5 = p = Sxy_new*Sxy_new/Syy
%endif
VPBROADCASTD m2, xm2 ; m2=i (all lanes get same values, we add the offset-per-lane, later)
cmpps m0, m3, m5, 1 ; m0 = (m3 < m5) ; (p_max < p) ; (p > p_max)
maxps m3, m5 ; m3=max(p_max,p)
; maxps here is faster than blendvps, despite blend having lower latency.
pand m2, m0 ; This version seems faster than sse41 pblendvb
pmaxsw m1, m2 ; SSE2 signed word, so it would work for N < 32768/4
add r4d, mmsize
cmp r4d, Nd
jb %%distortion_search
por m1, mm_const_int32_offsets ; max_idx offsets per individual lane (skipped in the inner loop)
movdqa m4, m1 ; needed for the aligned y[max_idx]+=1; processing
%if mmsize >= 32
; Merge parallel maximums round 8 (4 vs 4)
vextractf128 xm5, ym3, 1 ; xmm5 = ymm3[1x128] = ymm3[255..128b]
cmpps xm0, xm3, xm5, 1 ; m0 = (m3 < m5) = ( p[0x128] < p[1x128] )
vextracti128 xm2, ym1, 1 ; xmm2 = ymm1[1x128] = ymm1[255..128b]
BLENDVPS xm3, xm5, xm0 ; max_idx = m0 ? max_idx[1x128] : max_idx[0x128]
PBLENDVB xm1, xm2, xm0 ; p = m0 ? p[1x128] : p[0x128]
%endif
; Merge parallel maximums round 4 (2 vs 2)
; m3=p[3210]
movhlps xm5, xm3 ; m5=p[xx32]
cmpps xm0, xm3, xm5, 1 ; m0 = (m3 < m5) = ( p[1,0] < p[3,2] )
pshufd xm2, xm1, q3232
BLENDVPS xm3, xm5, xm0 ; max_idx = m0 ? max_idx[3,2] : max_idx[1,0]
PBLENDVB xm1, xm2, xm0 ; p = m0 ? p[3,2] : p[1,0]
; Merge parallel maximums final round (1 vs 1)
shufps xm0, xm3, xm3, q1111 ; m0 = m3[1] = p[1]
cmpss xm0, xm3, 5 ; m0 = !(m0 >= m3) = !( p[1] >= p[0] )
pshufd xm2, xm1, q1111
PBLENDVB xm1, xm2, xm0
movd dword r4d, xm1 ; zero extends to the rest of r4q
VBROADCASTSS m3, [tmpX + r4]
%{1}ps m7, m3 ; Sxy += X[max_idx]
VBROADCASTSS m5, [tmpY + r4]
%{1}ps m6, m5 ; Syy += Y[max_idx]
; We have to update a single element in Y[i]
; However writing 4 bytes and then doing 16 byte load in the inner loop
; could cause a stall due to breaking write forwarding.
VPBROADCASTD m1, xm1
pcmpeqd m1, m1, m4 ; exactly 1 element matches max_idx and this finds it
and r4d, ~(mmsize-1) ; align address down, so the value pointed by max_idx is inside a mmsize load
movaps m5, [tmpY + r4] ; m5 = Y[y3...ym...y0]
andps m1, mm_const_float_1 ; m1 = [ 0...1.0...0]
%{1}ps m5, m1 ; m5 = Y[y3...ym...y0] +/- [0...1.0...0]
movaps [tmpY + r4], m5 ; Y[max_idx] +-= 1.0;
%endmacro
;
; We need one more register for
; PIC relative addressing. Use this
; to count it in cglobal
;
%ifdef PIC
%define num_pic_regs 1
%else
%define num_pic_regs 0
%endif
;
; Pyramid Vector Quantization Search implementation
;
; float * inX - Unaligned (SIMD) access, it will be overread,
; but extra data is masked away.
; int32 * outY - Should be aligned and padded buffer.
; It is used as temp buffer.
; uint32 K - Number of pulses to have after quantizations.
; uint32 N - Number of vector elements. Must be 0 < N < 256
;
%macro PVQ_FAST_SEARCH 1
cglobal pvq_search%1, 4, 5+num_pic_regs, 11, 256*4, inX, outY, K, N
%define tmpX rsp
%define tmpY outYq
movaps m0, [const_float_abs_mask]
shl Nd, 2 ; N *= sizeof(float); also 32 bit operation zeroes the high 32 bits in 64 bit mode.
mov r4d, Nd
neg r4d
and r4d, mmsize-1
SET_PIC_BASE lea, r5, const_align_abs_edge ; rip+const
movups m2, [pic_base_const_align_abs_edge + r4 - mmsize]
add Nd, r4d ; N = align(N, mmsize)
lea r4d, [Nd - mmsize] ; N is rounded up (aligned up) to mmsize, so r4 can't become negative here, unless N=0.
movups m1, [inXq + r4]
andps m1, m2
movaps [tmpX + r4], m1 ; Sx = abs( X[N-1] )
align 16
%%loop_abs_sum:
sub r4d, mmsize
jc %%end_loop_abs_sum
movups m2, [inXq + r4]
andps m2, m0
movaps [tmpX + r4], m2 ; tmpX[i]=abs(X[i])
addps m1, m2 ; Sx += abs(X[i])
jmp %%loop_abs_sum
align 16
%%end_loop_abs_sum:
HSUMPS m1, m2 ; m1 = Sx
xorps m0, m0
comiss xm0, xm1 ;
jz %%zero_input ; if (Sx==0) goto zero_input
cvtsi2ss xm0, dword Kd ; m0 = K
%if USE_APPROXIMATION == 1
rcpss xm1, xm1 ; m1 = approx(1/Sx)
mulss xm0, xm1 ; m0 = K*(1/Sx)
%else
divss xm0, xm1 ; b = K/Sx
; b = K/max_x
%endif
VBROADCASTSS m0, xm0
lea r4d, [Nd - mmsize]
pxor m5, m5 ; Sy ( Sum of abs( y[i]) )
xorps m6, m6 ; Syy ( Sum of y[i]*y[i] )
xorps m7, m7 ; Sxy ( Sum of X[i]*y[i] )
align 16
%%loop_guess:
movaps m1, [tmpX + r4] ; m1 = X[i]
mulps m2, m0, m1 ; m2 = res*X[i]
cvtps2dq m2, m2 ; yt = (int)lrintf( res*X[i] )
paddd m5, m2 ; Sy += yt
cvtdq2ps m2, m2 ; yt = (float)yt
mulps m1, m2 ; m1 = X[i]*yt
movaps [tmpY + r4], m2 ; y[i] = m2
addps m7, m1 ; Sxy += m1;
mulps m2, m2 ; m2 = yt*yt
addps m6, m2 ; Syy += m2
sub r4d, mmsize
jnc %%loop_guess
HSUMPS m6, m1 ; Syy_norm
HADDD m5, m4 ; pulses
movd dword r4d, xm5 ; zero extends to the rest of r4q
sub Kd, r4d ; K -= pulses , also 32 bit operation zeroes high 32 bit in 64 bit mode.
jz %%finish ; K - pulses == 0
SET_HI_REG_MM_CONSTANT movaps, m8, const_float_0_5
SET_HI_REG_MM_CONSTANT movaps, m9, const_float_1
SET_HI_REG_MM_CONSTANT movdqa, m10, const_int32_offsets
; Use Syy/2 in distortion parameter calculations.
; Saves pre and post-caclulation to correct Y[] values.
; Same precision, since float mantisa is normalized.
; The SQRT approximation does differ.
HSUMPS m7, m0 ; Sxy_norm
mulps m6, mm_const_float_0_5
jc %%remove_pulses_loop ; K - pulses < 0
align 16 ; K - pulses > 0
%%add_pulses_loop:
PULSES_SEARCH add ; m6 Syy_norm ; m7 Sxy_norm
sub Kd, 1
jnz %%add_pulses_loop
addps m6, m6 ; Syy*=2
jmp %%finish
align 16
%%remove_pulses_loop:
PULSES_SEARCH sub ; m6 Syy_norm ; m7 Sxy_norm
add Kd, 1
jnz %%remove_pulses_loop
addps m6, m6 ; Syy*=2
align 16
%%finish:
lea r4d, [Nd - mmsize]
movaps m2, [const_float_sign_mask]
align 16
%%restore_sign_loop:
movaps m0, [tmpY + r4] ; m0 = Y[i]
movups m1, [inXq + r4] ; m1 = X[i]
andps m1, m2 ; m1 = sign(X[i])
orps m0, m1 ; m0 = Y[i]*sign
cvtps2dq m3, m0 ; m3 = (int)m0
movaps [outYq + r4], m3
sub r4d, mmsize
jnc %%restore_sign_loop
%%return:
%if ARCH_X86_64 == 0 ; sbrdsp
movss r0m, xm6 ; return (float)Syy_norm
fld dword r0m
%else
movaps m0, m6 ; return (float)Syy_norm
%endif
RET
align 16
%%zero_input:
lea r4d, [Nd - mmsize]
xorps m0, m0
%%zero_loop:
movaps [outYq + r4], m0
sub r4d, mmsize
jnc %%zero_loop
movaps m6, [const_float_1]
jmp %%return
%endmacro
; if 1, use a float op that give half precision but execute for around 3 cycles.
; On Skylake & Ryzen the division is much faster (around 11c/3),
; that makes the full precision code about 2% slower.
; Opus also does use rsqrt approximation in their intrinsics code.
%define USE_APPROXIMATION 1
INIT_XMM sse2
PVQ_FAST_SEARCH _approx
INIT_XMM sse4
PVQ_FAST_SEARCH _approx
%define USE_APPROXIMATION 0
INIT_XMM avx
PVQ_FAST_SEARCH _exact