libswscale/aarch64: add another hscale specialization

This specialization handles the case where filtersize is 4 mod 8, e.g.
12, 20, etc. Aarch64 was previously using the c function for this case.
This implementation speeds up that case significantly.

hscale_8_to_15__fs_12_dstW_512_c: 6234.1
hscale_8_to_15__fs_12_dstW_512_neon: 1505.6

Signed-off-by: Jonathan Swinney <jswinney@amazon.com>
Signed-off-by: Martin Storsjö <martin@martin.st>
This commit is contained in:
Swinney, Jonathan 2022-08-13 20:48:30 +00:00 committed by Martin Storsjö
parent 1af7797d21
commit 75ffca7eef
2 changed files with 117 additions and 8 deletions

View File

@ -91,6 +91,113 @@ function ff_hscale8to15_X8_neon, export=1
ret
endfunc
function ff_hscale8to15_X4_neon, export=1
// x0 SwsContext *c (not used)
// x1 int16_t *dst
// w2 int dstW
// x3 const uint8_t *src
// x4 const int16_t *filter
// x5 const int32_t *filterPos
// w6 int filterSize
// This function for filter sizes that are 4 mod 8. In other words, anything that's 0 mod 4 but not
// 0 mod 8. It also assumes that dstW is 0 mod 4.
lsl w7, w6, #1 // w7 = filterSize * 2
1:
ldp w8, w9, [x5] // filterPos[idx + 0], [idx + 1]
ldp w10, w11, [x5, #8] // filterPos[idx + 2], [idx + 3]
movi v16.2d, #0 // initialize accumulator for idx + 0
movi v17.2d, #0 // initialize accumulator for idx + 1
movi v18.2d, #0 // initialize accumulator for idx + 2
movi v19.2d, #0 // initialize accumulator for idx + 3
mov x12, x4 // filter pointer for idx + 0
add x13, x4, x7 // filter pointer for idx + 1
add x8, x3, w8, uxtw // srcp + filterPos[idx + 0]
add x9, x3, w9, uxtw // srcp + filterPos[idx + 1]
add x14, x13, x7 // filter pointer for idx + 2
add x10, x3, w10, uxtw // srcp + filterPos[idx + 2]
add x11, x3, w11, uxtw // srcp + filterPos[idx + 3]
mov w0, w6 // copy filterSize to a temp register, w0
add x5, x5, #16 // advance the filterPos pointer
add x15, x14, x7 // filter pointer for idx + 3
mov x16, xzr // temp register for offsetting filter pointers
2:
// This section loops over 8-wide chunks of filter size
ldr d4, [x8], #8 // load 8 bytes from srcp for idx + 0
ldr q0, [x12, x16] // load 8 values, 16 bytes from filter for idx + 0
ldr d5, [x9], #8 // load 8 bytes from srcp for idx + 1
ldr q1, [x13, x16] // load 8 values, 16 bytes from filter for idx + 1
uxtl v4.8h, v4.8b // unsigned extend long for idx + 0
uxtl v5.8h, v5.8b // unsigned extend long for idx + 1
ldr d6, [x10], #8 // load 8 bytes from srcp for idx + 2
ldr q2, [x14, x16] // load 8 values, 16 bytes from filter for idx + 2
smlal v16.4s, v0.4h, v4.4h // val += src[srcPos + j + 0..3] * filter[fs * i + j + 0..3], idx + 0
smlal v17.4s, v1.4h, v5.4h // val += src[srcPos + j + 0..3] * filter[fs * i + j + 0..3], idx + 1
ldr d7, [x11], #8 // load 8 bytes from srcp for idx + 3
ldr q3, [x15, x16] // load 8 values, 16 bytes from filter for idx + 3
sub w0, w0, #8 // decrement the remaining filterSize counter
smlal2 v16.4s, v0.8h, v4.8h // val += src[srcPos + j + 4..7] * filter[fs * i + j + 4..7], idx + 0
smlal2 v17.4s, v1.8h, v5.8h // val += src[srcPos + j + 4..7] * filter[fs * i + j + 4..7], idx + 1
uxtl v6.8h, v6.8b // unsigned extend long for idx + 2
uxtl v7.8h, v7.8b // unsigned extend long for idx + 3
smlal v18.4s, v2.4h, v6.4h // val += src[srcPos + j + 0..3] * filter[fs * i + j + 0..3], idx + 2
smlal v19.4s, v3.4h, v7.4h // val += src[srcPos + j + 0..3] * filter[fs * i + j + 0..3], idx + 3
cmp w0, #8 // are there at least 8 more elements in filter to consume?
add x16, x16, #16 // advance the offsetting register for filter values
smlal2 v18.4s, v2.8h, v6.8h // val += src[srcPos + j + 4..7] * filter[fs * i + j + 4..7], idx + 2
smlal2 v19.4s, v3.8h, v7.8h // val += src[srcPos + j + 4..7] * filter[fs * i + j + 4..7], idx + 3
b.ge 2b // branch back to inner loop
// complete the remaining 4 filter elements
sub x17, x7, #8 // calculate the offset of the filter pointer for the remaining 4 elements
ldr s4, [x8] // load 4 bytes from srcp for idx + 0
ldr d0, [x12, x17] // load 4 values, 8 bytes from filter for idx + 0
ldr s5, [x9] // load 4 bytes from srcp for idx + 1
ldr d1, [x13, x17] // load 4 values, 8 bytes from filter for idx + 1
uxtl v4.8h, v4.8b // unsigned extend long for idx + 0
uxtl v5.8h, v5.8b // unsigned extend long for idx + 1
ldr s6, [x10] // load 4 bytes from srcp for idx + 2
ldr d2, [x14, x17] // load 4 values, 8 bytes from filter for idx + 2
smlal v16.4s, v0.4h, v4.4h // val += src[srcPos + j + 0..3] * filter[fs * i + j + 0..3], idx + 0
smlal v17.4s, v1.4h, v5.4h // val += src[srcPos + j + 0..3] * filter[fs * i + j + 0..3], idx + 1
ldr s7, [x11] // load 4 bytes from srcp for idx + 3
ldr d3, [x15, x17] // load 4 values, 8 bytes from filter for idx + 3
uxtl v6.8h, v6.8b // unsigned extend long for idx + 2
uxtl v7.8h, v7.8b // unsigned extend long for idx + 3
addp v16.4s, v16.4s, v17.4s // horizontal pair adding for idx 0,1
smlal v18.4s, v2.4h, v6.4h // val += src[srcPos + j + 0..3] * filter[fs * i + j + 0..3], idx + 2
smlal v19.4s, v3.4h, v7.4h // val += src[srcPos + j + 0..3] * filter[fs * i + j + 0..3], idx + 3
addp v18.4s, v18.4s, v19.4s // horizontal pair adding for idx 2,3
addp v16.4s, v16.4s, v18.4s // final horizontal pair adding producing one vector with results for idx = 0..3
subs w2, w2, #4 // dstW -= 4
sqshrn v0.4h, v16.4s, #7 // shift and clip the 2x16-bit final values
st1 {v0.4h}, [x1], #8 // write to destination idx 0..3
add x4, x4, x7, lsl #2 // filter += (filterSize*2) * 4
b.gt 1b // loop until end of line
ret
endfunc
function ff_hscale8to15_4_neon, export=1
// x0 SwsContext *c (not used)
// x1 int16_t *dst

View File

@ -32,7 +32,8 @@ void ff_hscale ## from_bpc ## to ## to_bpc ## _ ## filter_n ## _ ## opt( \
SCALE_FUNC(filter_n, 8, 15, opt);
#define ALL_SCALE_FUNCS(opt) \
SCALE_FUNCS(4, opt); \
SCALE_FUNCS(X8, opt)
SCALE_FUNCS(X8, opt); \
SCALE_FUNCS(X4, opt)
ALL_SCALE_FUNCS(neon);
@ -47,13 +48,14 @@ void ff_yuv2planeX_8_neon(const int16_t *filter, int filterSize,
} \
} while (0)
#define ASSIGN_SCALE_FUNC(hscalefn, filtersize, opt) \
switch (filtersize) { \
case 4: ASSIGN_SCALE_FUNC2(hscalefn, 4, opt); break; \
default: if (filtersize % 8 == 0) \
ASSIGN_SCALE_FUNC2(hscalefn, X8, opt); \
break; \
}
#define ASSIGN_SCALE_FUNC(hscalefn, filtersize, opt) do { \
if (filtersize == 4) \
ASSIGN_SCALE_FUNC2(hscalefn, 4, opt); \
else if (filtersize % 8 == 0) \
ASSIGN_SCALE_FUNC2(hscalefn, X8, opt); \
else if (filtersize % 4 == 0 && filtersize % 8 != 0) \
ASSIGN_SCALE_FUNC2(hscalefn, X4, opt); \
} while (0)
av_cold void ff_sws_init_swscale_aarch64(SwsContext *c)
{