ref: 58a4ba072214e2b4a39d1d54821a426c2269e233
dir: /src/arm/64/looprestoration16.S/
/*
* Copyright © 2018, VideoLAN and dav1d authors
* Copyright © 2020, Martin Storsjo
* 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 "src/arm/asm.S"
#include "util.S"
// void dav1d_wiener_filter_h_16bpc_neon(int16_t *dst, const pixel (*left)[4],
// const pixel *src, ptrdiff_t stride,
// const int16_t fh[7], const intptr_t w,
// int h, enum LrEdgeFlags edges,
// const int bitdepth_max);
function wiener_filter_h_16bpc_neon, export=1
ldr w8, [sp] // bitdepth_max
ld1 {v0.8h}, [x4]
clz w8, w8
movi v30.4s, #1
sub w9, w8, #38 // -(bitdepth + 6)
sub w8, w8, #25 // -round_bits_h
neg w9, w9 // bitdepth + 6
dup v1.4s, w9
dup v29.4s, w8 // -round_bits_h
movi v31.8h, #0x20, lsl #8 // 1 << 13 = 8192
ushl v30.4s, v30.4s, v1.4s // 1 << (bitdepth + 6)
mov w8, w5
// Calculate mid_stride
add w10, w5, #7
bic w10, w10, #7
lsl w10, w10, #1
// Clear the last unused element of v0, to allow filtering a single
// pixel with one plain mul+addv.
ins v0.h[7], wzr
// Set up pointers for reading/writing alternate rows
add x12, x0, x10
lsl w10, w10, #1
add x13, x2, x3
lsl x3, x3, #1
// Subtract the width from mid_stride
sub x10, x10, w5, uxtw #1
// For w >= 8, we read (w+5)&~7+8 pixels, for w < 8 we read 16 pixels.
cmp w5, #8
add w11, w5, #13
bic w11, w11, #7
b.ge 1f
mov w11, #16
1:
sub x3, x3, w11, uxtw #1
// Set up the src pointers to include the left edge, for LR_HAVE_LEFT, left == NULL
tst w7, #1 // LR_HAVE_LEFT
b.eq 2f
// LR_HAVE_LEFT
cbnz x1, 0f
// left == NULL
sub x2, x2, #6
sub x13, x13, #6
b 1f
0: // LR_HAVE_LEFT, left != NULL
2: // !LR_HAVE_LEFT, increase the stride.
// For this case we don't read the left 3 pixels from the src pointer,
// but shift it as if we had done that.
add x3, x3, #6
1: // Loop vertically
ld1 {v2.8h, v3.8h}, [x2], #32
ld1 {v4.8h, v5.8h}, [x13], #32
tst w7, #1 // LR_HAVE_LEFT
b.eq 0f
cbz x1, 2f
// LR_HAVE_LEFT, left != NULL
ld1 {v1.d}[1], [x1], #8
// Move x2/x13 back to account for the last 3 pixels we loaded earlier,
// which we'll shift out.
sub x2, x2, #6
sub x13, x13, #6
ld1 {v6.d}[1], [x1], #8
ext v3.16b, v2.16b, v3.16b, #10
ext v2.16b, v1.16b, v2.16b, #10
ext v5.16b, v4.16b, v5.16b, #10
ext v4.16b, v6.16b, v4.16b, #10
b 2f
0:
// !LR_HAVE_LEFT, fill v1 with the leftmost pixel
// and shift v2/v3 to have 3x the first pixel at the front.
dup v1.8h, v2.h[0]
dup v6.8h, v4.h[0]
// Move x2 back to account for the last 3 pixels we loaded before,
// which we shifted out.
sub x2, x2, #6
sub x13, x13, #6
ext v3.16b, v2.16b, v3.16b, #10
ext v2.16b, v1.16b, v2.16b, #10
ext v5.16b, v4.16b, v5.16b, #10
ext v4.16b, v6.16b, v4.16b, #10
2:
tst w7, #2 // LR_HAVE_RIGHT
b.ne 4f
// If we'll need to pad the right edge, load that byte to pad with
// here since we can find it pretty easily from here.
sub w9, w5, #14
ldr h27, [x2, w9, sxtw #1]
ldr h28, [x13, w9, sxtw #1]
// Fill v27/v28 with the right padding pixel
dup v27.8h, v27.h[0]
dup v28.8h, v28.h[0]
3: // !LR_HAVE_RIGHT
// If we'll have to pad the right edge we need to quit early here.
cmp w5, #11
b.ge 4f // If w >= 11, all used input pixels are valid
cmp w5, #7
b.ge 5f // If w >= 7, we can filter 4 pixels
b 6f
4: // Loop horizontally
.macro ushll_sz d0, d1, src, shift, wd
ushll \d0\().4s, \src\().4h, \shift
.ifc \wd, .8h
ushll2 \d1\().4s, \src\().8h, \shift
.endif
.endm
.macro add_sz d0, d1, s0, s1, c, wd
add \d0\().4s, \s0\().4s, \c\().4s
.ifc \wd, .8h
add \d1\().4s, \s1\().4s, \c\().4s
.endif
.endm
.macro srshl_sz d0, d1, s0, s1, c, wd
srshl \d0\().4s, \s0\().4s, \c\().4s
.ifc \wd, .8h
srshl \d1\().4s, \s1\().4s, \c\().4s
.endif
.endm
.macro sqxtun_sz dst, s0, s1, wd
sqxtun \dst\().4h, \s0\().4s
.ifc \wd, .8h
sqxtun2 \dst\().8h, \s1\().4s
.endif
.endm
.macro filter wd
// Interleaving the mul/mla chains actually hurts performance
// significantly on Cortex A53, thus keeping mul/mla tightly
// chained like this.
ext v16.16b, v2.16b, v3.16b, #2
ext v17.16b, v2.16b, v3.16b, #4
ext v18.16b, v2.16b, v3.16b, #6
ext v19.16b, v2.16b, v3.16b, #8
ext v20.16b, v2.16b, v3.16b, #10
ext v21.16b, v2.16b, v3.16b, #12
ushll_sz v6, v7, v18, #7, \wd
smlal v6.4s, v2.4h, v0.h[0]
smlal v6.4s, v16.4h, v0.h[1]
smlal v6.4s, v17.4h, v0.h[2]
smlal v6.4s, v18.4h, v0.h[3]
smlal v6.4s, v19.4h, v0.h[4]
smlal v6.4s, v20.4h, v0.h[5]
smlal v6.4s, v21.4h, v0.h[6]
.ifc \wd, .8h
smlal2 v7.4s, v2.8h, v0.h[0]
smlal2 v7.4s, v16.8h, v0.h[1]
smlal2 v7.4s, v17.8h, v0.h[2]
smlal2 v7.4s, v18.8h, v0.h[3]
smlal2 v7.4s, v19.8h, v0.h[4]
smlal2 v7.4s, v20.8h, v0.h[5]
smlal2 v7.4s, v21.8h, v0.h[6]
.endif
ext v19.16b, v4.16b, v5.16b, #2
ext v20.16b, v4.16b, v5.16b, #4
ext v21.16b, v4.16b, v5.16b, #6
ext v22.16b, v4.16b, v5.16b, #8
ext v23.16b, v4.16b, v5.16b, #10
ext v24.16b, v4.16b, v5.16b, #12
ushll_sz v16, v17, v21, #7, \wd
smlal v16.4s, v4.4h, v0.h[0]
smlal v16.4s, v19.4h, v0.h[1]
smlal v16.4s, v20.4h, v0.h[2]
smlal v16.4s, v21.4h, v0.h[3]
smlal v16.4s, v22.4h, v0.h[4]
smlal v16.4s, v23.4h, v0.h[5]
smlal v16.4s, v24.4h, v0.h[6]
.ifc \wd, .8h
smlal2 v17.4s, v4.8h, v0.h[0]
smlal2 v17.4s, v19.8h, v0.h[1]
smlal2 v17.4s, v20.8h, v0.h[2]
smlal2 v17.4s, v21.8h, v0.h[3]
smlal2 v17.4s, v22.8h, v0.h[4]
smlal2 v17.4s, v23.8h, v0.h[5]
smlal2 v17.4s, v24.8h, v0.h[6]
.endif
mvni v24\wd, #0x80, lsl #8 // 0x7fff = (1 << 15) - 1
add_sz v6, v7, v6, v7, v30, \wd
add_sz v16, v17, v16, v17, v30, \wd
srshl_sz v6, v7, v6, v7, v29, \wd
srshl_sz v16, v17, v16, v17, v29, \wd
sqxtun_sz v6, v6, v7, \wd
sqxtun_sz v7, v16, v17, \wd
umin v6\wd, v6\wd, v24\wd
umin v7\wd, v7\wd, v24\wd
sub v6\wd, v6\wd, v31\wd
sub v7\wd, v7\wd, v31\wd
.endm
filter .8h
st1 {v6.8h}, [x0], #16
st1 {v7.8h}, [x12], #16
subs w5, w5, #8
b.le 9f
tst w7, #2 // LR_HAVE_RIGHT
mov v2.16b, v3.16b
mov v4.16b, v5.16b
ld1 {v3.8h}, [x2], #16
ld1 {v5.8h}, [x13], #16
b.ne 4b // If we don't need to pad, just keep filtering.
b 3b // If we need to pad, check how many pixels we have left.
5: // Filter 4 pixels, 7 <= w < 11
filter .4h
st1 {v6.4h}, [x0], #8
st1 {v7.4h}, [x12], #8
subs w5, w5, #4 // 3 <= w < 7
ext v2.16b, v2.16b, v3.16b, #8
ext v3.16b, v3.16b, v3.16b, #8
ext v4.16b, v4.16b, v5.16b, #8
ext v5.16b, v5.16b, v5.16b, #8
6: // Pad the right edge and filter the last few pixels.
// w < 7, w+3 pixels valid in v2-v3
cmp w5, #5
b.lt 7f
b.gt 8f
// w == 5, 8 pixels valid in v2, v3 invalid
mov v3.16b, v27.16b
mov v5.16b, v28.16b
b 88f
7: // 1 <= w < 5, 4-7 pixels valid in v2
sub w9, w5, #1
// w9 = (pixels valid - 4)
adr x11, L(variable_shift_tbl)
ldrh w9, [x11, w9, uxtw #1]
sub x11, x11, w9, uxth
mov v3.16b, v27.16b
mov v5.16b, v28.16b
br x11
44: // 4 pixels valid in v2/v4, fill the high half with padding.
ins v2.d[1], v3.d[0]
ins v4.d[1], v5.d[0]
b 88f
// Shift v2 right, shifting out invalid pixels,
// shift v2 left to the original offset, shifting in padding pixels.
55: // 5 pixels valid
ext v2.16b, v2.16b, v2.16b, #10
ext v2.16b, v2.16b, v3.16b, #6
ext v4.16b, v4.16b, v4.16b, #10
ext v4.16b, v4.16b, v5.16b, #6
b 88f
66: // 6 pixels valid, fill the upper 2 pixels with padding.
ins v2.s[3], v3.s[0]
ins v4.s[3], v5.s[0]
b 88f
77: // 7 pixels valid, fill the last pixel with padding.
ins v2.h[7], v3.h[0]
ins v4.h[7], v5.h[0]
b 88f
L(variable_shift_tbl):
.hword L(variable_shift_tbl) - 44b
.hword L(variable_shift_tbl) - 55b
.hword L(variable_shift_tbl) - 66b
.hword L(variable_shift_tbl) - 77b
8: // w > 5, w == 6, 9 pixels valid in v2-v3, 1 pixel valid in v3
ins v27.h[0], v3.h[0]
ins v28.h[0], v5.h[0]
mov v3.16b, v27.16b
mov v5.16b, v28.16b
88:
// w < 7, v2-v3 padded properly
cmp w5, #4
b.lt 888f
// w >= 4, filter 4 pixels
filter .4h
st1 {v6.4h}, [x0], #8
st1 {v7.4h}, [x12], #8
subs w5, w5, #4 // 0 <= w < 4
ext v2.16b, v2.16b, v3.16b, #8
ext v4.16b, v4.16b, v5.16b, #8
b.eq 9f
888: // 1 <= w < 4, filter 1 pixel at a time
smull v6.4s, v2.4h, v0.4h
smull2 v7.4s, v2.8h, v0.8h
smull v16.4s, v4.4h, v0.4h
smull2 v17.4s, v4.8h, v0.8h
add v6.4s, v6.4s, v7.4s
add v16.4s, v16.4s, v17.4s
addv s6, v6.4s
addv s7, v16.4s
dup v16.4h, v2.h[3]
ins v16.h[1], v4.h[3]
ins v6.s[1], v7.s[0]
mvni v24.4h, #0x80, lsl #8 // 0x7fff = (1 << 15) - 1
ushll v16.4s, v16.4h, #7
add v6.4s, v6.4s, v30.4s
add v6.4s, v6.4s, v16.4s
srshl v6.4s, v6.4s, v29.4s
sqxtun v6.4h, v6.4s
umin v6.4h, v6.4h, v24.4h
sub v6.4h, v6.4h, v31.4h
st1 {v6.h}[0], [x0], #2
st1 {v6.h}[1], [x12], #2
subs w5, w5, #1
ext v2.16b, v2.16b, v3.16b, #2
ext v4.16b, v4.16b, v5.16b, #2
b.gt 888b
9:
subs w6, w6, #2
b.le 0f
// Jump to the next row and loop horizontally
add x0, x0, x10
add x12, x12, x10
add x2, x2, x3
add x13, x13, x3
mov w5, w8
b 1b
0:
ret
.purgem filter
endfunc
// void dav1d_wiener_filter_v_16bpc_neon(pixel *dst, ptrdiff_t stride,
// const int16_t *mid, int w, int h,
// const int16_t fv[7], enum LrEdgeFlags edges,
// ptrdiff_t mid_stride, const int bitdepth_max);
function wiener_filter_v_16bpc_neon, export=1
ldr w8, [sp] // bitdepth_max
ld1 {v0.8h}, [x5]
dup v31.8h, w8
clz w8, w8
movi v1.8h, #128
sub w8, w8, #11 // round_bits_v
add v1.8h, v1.8h, v0.8h
dup v30.4s, w8
mov w8, w4
neg v30.4s, v30.4s // -round_bits_v
// Calculate the number of rows to move back when looping vertically
mov w11, w4
tst w6, #4 // LR_HAVE_TOP
b.eq 0f
sub x2, x2, x7, lsl #1
add w11, w11, #2
0:
tst w6, #8 // LR_HAVE_BOTTOM
b.eq 1f
add w11, w11, #2
1: // Start of horizontal loop; start one vertical filter slice.
// Load rows into v16-v19 and pad properly.
tst w6, #4 // LR_HAVE_TOP
ld1 {v16.8h}, [x2], x7
b.eq 2f
// LR_HAVE_TOP
ld1 {v18.8h}, [x2], x7
mov v17.16b, v16.16b
ld1 {v19.8h}, [x2], x7
b 3f
2: // !LR_HAVE_TOP
mov v17.16b, v16.16b
mov v18.16b, v16.16b
mov v19.16b, v16.16b
3:
cmp w4, #4
b.lt 5f
// Start filtering normally; fill in v20-v22 with unique rows.
ld1 {v20.8h}, [x2], x7
ld1 {v21.8h}, [x2], x7
ld1 {v22.8h}, [x2], x7
4:
.macro filter compare
subs w4, w4, #1
// Interleaving the mul/mla chains actually hurts performance
// significantly on Cortex A53, thus keeping mul/mla tightly
// chained like this.
smull v2.4s, v16.4h, v0.h[0]
smlal v2.4s, v17.4h, v0.h[1]
smlal v2.4s, v18.4h, v0.h[2]
smlal v2.4s, v19.4h, v1.h[3]
smlal v2.4s, v20.4h, v0.h[4]
smlal v2.4s, v21.4h, v0.h[5]
smlal v2.4s, v22.4h, v0.h[6]
smull2 v3.4s, v16.8h, v0.h[0]
smlal2 v3.4s, v17.8h, v0.h[1]
smlal2 v3.4s, v18.8h, v0.h[2]
smlal2 v3.4s, v19.8h, v1.h[3]
smlal2 v3.4s, v20.8h, v0.h[4]
smlal2 v3.4s, v21.8h, v0.h[5]
smlal2 v3.4s, v22.8h, v0.h[6]
srshl v2.4s, v2.4s, v30.4s // round_bits_v
srshl v3.4s, v3.4s, v30.4s
sqxtun v2.4h, v2.4s
sqxtun2 v2.8h, v3.4s
umin v2.8h, v2.8h, v31.8h // bitdepth_max
st1 {v2.8h}, [x0], x1
.if \compare
cmp w4, #4
.else
b.le 9f
.endif
mov v16.16b, v17.16b
mov v17.16b, v18.16b
mov v18.16b, v19.16b
mov v19.16b, v20.16b
mov v20.16b, v21.16b
mov v21.16b, v22.16b
.endm
filter 1
b.lt 7f
ld1 {v22.8h}, [x2], x7
b 4b
5: // Less than 4 rows in total; not all of v20-v21 are filled yet.
tst w6, #8 // LR_HAVE_BOTTOM
b.eq 6f
// LR_HAVE_BOTTOM
cmp w4, #2
// We load at least 2 rows in all cases.
ld1 {v20.8h}, [x2], x7
ld1 {v21.8h}, [x2], x7
b.gt 53f // 3 rows in total
b.eq 52f // 2 rows in total
51: // 1 row in total, v19 already loaded, load edge into v20-v22.
mov v22.16b, v21.16b
b 8f
52: // 2 rows in total, v19 already loaded, load v20 with content data
// and 2 rows of edge.
ld1 {v22.8h}, [x2], x7
mov v23.16b, v22.16b
b 8f
53:
// 3 rows in total, v19 already loaded, load v20 and v21 with content
// and 2 rows of edge.
ld1 {v22.8h}, [x2], x7
ld1 {v23.8h}, [x2], x7
mov v24.16b, v23.16b
b 8f
6:
// !LR_HAVE_BOTTOM
cmp w4, #2
b.gt 63f // 3 rows in total
b.eq 62f // 2 rows in total
61: // 1 row in total, v19 already loaded, pad that into v20-v22.
mov v20.16b, v19.16b
mov v21.16b, v19.16b
mov v22.16b, v19.16b
b 8f
62: // 2 rows in total, v19 already loaded, load v20 and pad that into v21-v23.
ld1 {v20.8h}, [x2], x7
mov v21.16b, v20.16b
mov v22.16b, v20.16b
mov v23.16b, v20.16b
b 8f
63:
// 3 rows in total, v19 already loaded, load v20 and v21 and pad v21 into v22-v24.
ld1 {v20.8h}, [x2], x7
ld1 {v21.8h}, [x2], x7
mov v22.16b, v21.16b
mov v23.16b, v21.16b
mov v24.16b, v21.16b
b 8f
7:
// All registers up to v21 are filled already, 3 valid rows left.
// < 4 valid rows left; fill in padding and filter the last
// few rows.
tst w6, #8 // LR_HAVE_BOTTOM
b.eq 71f
// LR_HAVE_BOTTOM; load 2 rows of edge.
ld1 {v22.8h}, [x2], x7
ld1 {v23.8h}, [x2], x7
mov v24.16b, v23.16b
b 8f
71:
// !LR_HAVE_BOTTOM, pad 3 rows
mov v22.16b, v21.16b
mov v23.16b, v21.16b
mov v24.16b, v21.16b
8: // At this point, all registers up to v22-v24 are loaded with
// edge/padding (depending on how many rows are left).
filter 0 // This branches to 9f when done
mov v22.16b, v23.16b
mov v23.16b, v24.16b
b 8b
9: // End of one vertical slice.
subs w3, w3, #8
b.le 0f
// Move pointers back up to the top and loop horizontally.
msub x0, x1, x8, x0
msub x2, x7, x11, x2
add x0, x0, #16
add x2, x2, #16
mov w4, w8
b 1b
0:
ret
.purgem filter
endfunc
// void dav1d_copy_narrow_16bpc_neon(pixel *dst, ptrdiff_t stride,
// const pixel *src, int w, int h);
function copy_narrow_16bpc_neon, export=1
adr x5, L(copy_narrow_tbl)
ldrh w6, [x5, w3, uxtw #1]
sub x5, x5, w6, uxth
br x5
10:
add x7, x0, x1
lsl x1, x1, #1
18:
subs w4, w4, #8
b.lt 110f
ld1 {v0.8h}, [x2], #16
st1 {v0.h}[0], [x0], x1
st1 {v0.h}[1], [x7], x1
st1 {v0.h}[2], [x0], x1
st1 {v0.h}[3], [x7], x1
st1 {v0.h}[4], [x0], x1
st1 {v0.h}[5], [x7], x1
st1 {v0.h}[6], [x0], x1
st1 {v0.h}[7], [x7], x1
b.le 0f
b 18b
110:
add w4, w4, #8
asr x1, x1, #1
11:
subs w4, w4, #1
ld1 {v0.h}[0], [x2], #2
st1 {v0.h}[0], [x0], x1
b.gt 11b
0:
ret
20:
add x7, x0, x1
lsl x1, x1, #1
24:
subs w4, w4, #4
b.lt 210f
ld1 {v0.4s}, [x2], #16
st1 {v0.s}[0], [x0], x1
st1 {v0.s}[1], [x7], x1
st1 {v0.s}[2], [x0], x1
st1 {v0.s}[3], [x7], x1
b.le 0f
b 24b
210:
add w4, w4, #4
asr x1, x1, #1
22:
subs w4, w4, #1
ld1 {v0.s}[0], [x2], #4
st1 {v0.s}[0], [x0], x1
b.gt 22b
0:
ret
30:
ldr w5, [x2]
ldrh w6, [x2, #4]
add x2, x2, #6
subs w4, w4, #1
str w5, [x0]
strh w6, [x0, #4]
add x0, x0, x1
b.gt 30b
ret
40:
add x7, x0, x1
lsl x1, x1, #1
42:
subs w4, w4, #2
b.lt 41f
ld1 {v0.2d}, [x2], #16
st1 {v0.d}[0], [x0], x1
st1 {v0.d}[1], [x7], x1
b.le 0f
b 42b
41:
ld1 {v0.4h}, [x2]
st1 {v0.4h}, [x0]
0:
ret
50:
ldr x5, [x2]
ldrh w6, [x2, #8]
add x2, x2, #10
subs w4, w4, #1
str x5, [x0]
strh w6, [x0, #8]
add x0, x0, x1
b.gt 50b
ret
60:
ldr x5, [x2]
ldr w6, [x2, #8]
add x2, x2, #12
subs w4, w4, #1
str x5, [x0]
str w6, [x0, #8]
add x0, x0, x1
b.gt 60b
ret
70:
ldr x5, [x2]
ldr w6, [x2, #8]
ldrh w7, [x2, #12]
add x2, x2, #14
subs w4, w4, #1
str x5, [x0]
str w6, [x0, #8]
strh w7, [x0, #12]
add x0, x0, x1
b.gt 70b
ret
L(copy_narrow_tbl):
.hword 0
.hword L(copy_narrow_tbl) - 10b
.hword L(copy_narrow_tbl) - 20b
.hword L(copy_narrow_tbl) - 30b
.hword L(copy_narrow_tbl) - 40b
.hword L(copy_narrow_tbl) - 50b
.hword L(copy_narrow_tbl) - 60b
.hword L(copy_narrow_tbl) - 70b
endfunc