ffmpeg/libavutil/riscv/float_dsp_rvv.S
Rémi Denis-Courmont 96a83ceea4 riscv: fix scalar product initialisation
VSETVLI xd, x0, ...' has rather nonobvious semantics:
- If xd is x0, then it preserves the current vector length.
- If xd is not x0, it sets the vector length to the supported maximum.

Also somewhat confusingly, while VMV.X.S always does its thing
regardless of the selected vector length, VMV.S.X does _nothing_ if the
selected vector length is zero.

So the current code breaks fails to initialise the accumulator if we
are unlucky to have a selected vector length of zero on entry. Fix it
by forcing the vector length to one.
2022-10-13 10:17:38 +02:00

238 lines
5.9 KiB
ArmAsm

/*
* Copyright © 2022 Rémi Denis-Courmont.
*
* 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 "asm.S"
// (a0) = (a1) * (a2) [0..a3-1]
func ff_vector_fmul_rvv, zve32f
1:
vsetvli t0, a3, e32, m1, ta, ma
vle32.v v16, (a1)
sub a3, a3, t0
vle32.v v24, (a2)
sh2add a1, t0, a1
vfmul.vv v16, v16, v24
sh2add a2, t0, a2
vse32.v v16, (a0)
sh2add a0, t0, a0
bnez a3, 1b
ret
endfunc
// (a0) += (a1) * fa0 [0..a2-1]
func ff_vector_fmac_scalar_rvv, zve32f
NOHWF fmv.w.x fa0, a2
NOHWF mv a2, a3
1:
vsetvli t0, a2, e32, m1, ta, ma
slli t1, t0, 2
vle32.v v24, (a1)
sub a2, a2, t0
vle32.v v16, (a0)
sh2add a1, t0, a1
vfmacc.vf v16, fa0, v24
vse32.v v16, (a0)
sh2add a0, t0, a0
bnez a2, 1b
ret
endfunc
// (a0) = (a1) * fa0 [0..a2-1]
func ff_vector_fmul_scalar_rvv, zve32f
NOHWF fmv.w.x fa0, a2
NOHWF mv a2, a3
1:
vsetvli t0, a2, e32, m1, ta, ma
vle32.v v16, (a1)
sub a2, a2, t0
vfmul.vf v16, v16, fa0
sh2add a1, t0, a1
vse32.v v16, (a0)
sh2add a0, t0, a0
bnez a2, 1b
ret
endfunc
func ff_vector_fmul_window_rvv, zve32f
// a0: dst, a1: src0, a2: src1, a3: window, a4: length
addi t0, a4, -1
add t1, t0, a4
sh2add a2, t0, a2
sh2add t0, t1, a0
sh2add t3, t1, a3
li t1, -4 // byte stride
1:
vsetvli t2, a4, e32, m1, ta, ma
vle32.v v16, (a1)
slli t4, t2, 2
vlse32.v v20, (a2), t1
sub a4, a4, t2
vle32.v v24, (a3)
add a1, a1, t4
vlse32.v v28, (t3), t1
sub a2, a2, t4
vfmul.vv v0, v16, v28
add a3, a3, t4
vfmul.vv v8, v16, v24
sub t3, t3, t4
vfnmsac.vv v0, v20, v24
vfmacc.vv v8, v20, v28
vse32.v v0, (a0)
add a0, a0, t4
vsse32.v v8, (t0), t1
sub t0, t0, t4
bnez a4, 1b
ret
endfunc
// (a0) = (a1) * (a2) + (a3) [0..a4-1]
func ff_vector_fmul_add_rvv, zve32f
1:
vsetvli t0, a4, e32, m1, ta, ma
vle32.v v8, (a1)
sub a4, a4, t0
vle32.v v16, (a2)
sh2add a1, t0, a1
vle32.v v24, (a3)
sh2add a2, t0, a2
vfmadd.vv v8, v16, v24
sh2add a3, t0, a3
vse32.v v8, (a0)
sh2add a0, t0, a0
bnez a4, 1b
ret
endfunc
// (a0) = (a1) * reverse(a2) [0..a3-1]
func ff_vector_fmul_reverse_rvv, zve32f
sh2add a2, a3, a2
li t2, -4 // byte stride
addi a2, a2, -4
1:
vsetvli t0, a3, e32, m1, ta, ma
slli t1, t0, 2
vle32.v v16, (a1)
sub a3, a3, t0
vlse32.v v24, (a2), t2
add a1, a1, t1
vfmul.vv v16, v16, v24
sub a2, a2, t1
vse32.v v16, (a0)
add a0, a0, t1
bnez a3, 1b
ret
endfunc
// (a0) = (a0) + (a1), (a1) = (a0) - (a1) [0..a2-1]
func ff_butterflies_float_rvv, zve32f
1:
vsetvli t0, a2, e32, m1, ta, ma
vle32.v v16, (a0)
sub a2, a2, t0
vle32.v v24, (a1)
vfadd.vv v0, v16, v24
vfsub.vv v8, v16, v24
vse32.v v0, (a0)
sh2add a0, t0, a0
vse32.v v8, (a1)
sh2add a1, t0, a1
bnez a2, 1b
ret
endfunc
// a0 = (a0).(a1) [0..a2-1]
func ff_scalarproduct_float_rvv, zve32f
vsetivli zero, 1, e32, m1, ta, ma
vmv.s.x v8, zero
1:
vsetvli t0, a2, e32, m1, ta, ma
vle32.v v16, (a0)
sub a2, a2, t0
vle32.v v24, (a1)
sh2add a0, t0, a0
vfmul.vv v16, v16, v24
sh2add a1, t0, a1
vfredusum.vs v8, v16, v8
bnez a2, 1b
vfmv.f.s fa0, v8
NOHWF fmv.x.w a0, fa0
ret
endfunc
// (a0) = (a1) * (a2) [0..a3-1]
func ff_vector_dmul_rvv, zve64d
1:
vsetvli t0, a3, e64, m1, ta, ma
vle64.v v16, (a1)
sub a3, a3, t0
vle64.v v24, (a2)
sh3add a1, t0, a1
vfmul.vv v16, v16, v24
sh3add a2, t0, a2
vse64.v v16, (a0)
sh3add a0, t0, a0
bnez a3, 1b
ret
endfunc
// (a0) += (a1) * fa0 [0..a2-1]
func ff_vector_dmac_scalar_rvv, zve64d
NOHWD fmv.d.x fa0, a2
NOHWD mv a2, a3
1:
vsetvli t0, a2, e64, m1, ta, ma
vle64.v v24, (a1)
sub a2, a2, t0
vle64.v v16, (a0)
sh3add a1, t0, a1
vfmacc.vf v16, fa0, v24
vse64.v v16, (a0)
sh3add a0, t0, a0
bnez a2, 1b
ret
endfunc
// (a0) = (a1) * fa0 [0..a2-1]
func ff_vector_dmul_scalar_rvv, zve64d
NOHWD fmv.d.x fa0, a2
NOHWD mv a2, a3
1:
vsetvli t0, a2, e64, m1, ta, ma
vle64.v v16, (a1)
sub a2, a2, t0
vfmul.vf v16, v16, fa0
sh3add a1, t0, a1
vse64.v v16, (a0)
sh3add a0, t0, a0
bnez a2, 1b
ret
endfunc