198 lines
5.9 KiB
NASM
198 lines
5.9 KiB
NASM
;
|
|
; Copyright (c) 2010 The Webm project authors. All Rights Reserved.
|
|
;
|
|
; Use of this source code is governed by a BSD-style license
|
|
; that can be found in the LICENSE file in the root of the source
|
|
; tree. An additional intellectual property rights grant can be found
|
|
; in the file PATENTS. All contributing project authors may
|
|
; be found in the AUTHORS file in the root of the source tree.
|
|
;
|
|
|
|
|
|
EXPORT |idct_dequant_full_2x_neon|
|
|
ARM
|
|
REQUIRE8
|
|
PRESERVE8
|
|
|
|
AREA ||.text||, CODE, READONLY, ALIGN=2
|
|
;void idct_dequant_full_2x_neon(short *q, short *dq, unsigned char *pre,
|
|
; unsigned char *dst, int pitch, int stride);
|
|
; r0 *q,
|
|
; r1 *dq,
|
|
; r2 *pre
|
|
; r3 *dst
|
|
; sp pitch
|
|
; sp+4 stride
|
|
|idct_dequant_full_2x_neon| PROC
|
|
vld1.16 {q0, q1}, [r1] ; dq (same l/r)
|
|
vld1.16 {q2, q3}, [r0] ; l q
|
|
ldr r1, [sp] ; pitch
|
|
add r0, r0, #32
|
|
vld1.16 {q4, q5}, [r0] ; r q
|
|
add r12, r2, #4
|
|
; interleave the predictors
|
|
vld1.32 {d28[0]}, [r2], r1 ; l pre
|
|
vld1.32 {d28[1]}, [r12], r1 ; r pre
|
|
vld1.32 {d29[0]}, [r2], r1
|
|
vld1.32 {d29[1]}, [r12], r1
|
|
vld1.32 {d30[0]}, [r2], r1
|
|
vld1.32 {d30[1]}, [r12], r1
|
|
vld1.32 {d31[0]}, [r2]
|
|
vld1.32 {d31[1]}, [r12]
|
|
|
|
adr r2, cospi8sqrt2minus1 ; pointer to the first constant
|
|
|
|
; dequant: q[i] = q[i] * dq[i]
|
|
vmul.i16 q2, q2, q0
|
|
vmul.i16 q3, q3, q1
|
|
vmul.i16 q4, q4, q0
|
|
vmul.i16 q5, q5, q1
|
|
|
|
vld1.16 {d0}, [r2]
|
|
|
|
; q2: l0r0 q3: l8r8
|
|
; q4: l4r4 q5: l12r12
|
|
vswp d5, d8
|
|
vswp d7, d10
|
|
|
|
; _CONSTANTS_ * 4,12 >> 16
|
|
; q6: 4 * sinpi : c1/temp1
|
|
; q7: 12 * sinpi : d1/temp2
|
|
; q8: 4 * cospi
|
|
; q9: 12 * cospi
|
|
vqdmulh.s16 q6, q4, d0[2] ; sinpi8sqrt2
|
|
vqdmulh.s16 q7, q5, d0[2]
|
|
vqdmulh.s16 q8, q4, d0[0] ; cospi8sqrt2minus1
|
|
vqdmulh.s16 q9, q5, d0[0]
|
|
|
|
vqadd.s16 q10, q2, q3 ; a1 = 0 + 8
|
|
vqsub.s16 q11, q2, q3 ; b1 = 0 - 8
|
|
|
|
; vqdmulh only accepts signed values. this was a problem because
|
|
; our constant had the high bit set, and was treated as a negative value.
|
|
; vqdmulh also doubles the value before it shifts by 16. we need to
|
|
; compensate for this. in the case of sinpi8sqrt2, the lowest bit is 0,
|
|
; so we can shift the constant without losing precision. this avoids
|
|
; shift again afterward, but also avoids the sign issue. win win!
|
|
; for cospi8sqrt2minus1 the lowest bit is 1, so we lose precision if we
|
|
; pre-shift it
|
|
vshr.s16 q8, q8, #1
|
|
vshr.s16 q9, q9, #1
|
|
|
|
; q4: 4 + 4 * cospi : d1/temp1
|
|
; q5: 12 + 12 * cospi : c1/temp2
|
|
vqadd.s16 q4, q4, q8
|
|
vqadd.s16 q5, q5, q9
|
|
|
|
; c1 = temp1 - temp2
|
|
; d1 = temp1 + temp2
|
|
vqsub.s16 q2, q6, q5
|
|
vqadd.s16 q3, q4, q7
|
|
|
|
; [0]: a1+d1
|
|
; [1]: b1+c1
|
|
; [2]: b1-c1
|
|
; [3]: a1-d1
|
|
vqadd.s16 q4, q10, q3
|
|
vqadd.s16 q5, q11, q2
|
|
vqsub.s16 q6, q11, q2
|
|
vqsub.s16 q7, q10, q3
|
|
|
|
; rotate
|
|
vtrn.32 q4, q6
|
|
vtrn.32 q5, q7
|
|
vtrn.16 q4, q5
|
|
vtrn.16 q6, q7
|
|
; idct loop 2
|
|
; q4: l 0, 4, 8,12 r 0, 4, 8,12
|
|
; q5: l 1, 5, 9,13 r 1, 5, 9,13
|
|
; q6: l 2, 6,10,14 r 2, 6,10,14
|
|
; q7: l 3, 7,11,15 r 3, 7,11,15
|
|
|
|
; q8: 1 * sinpi : c1/temp1
|
|
; q9: 3 * sinpi : d1/temp2
|
|
; q10: 1 * cospi
|
|
; q11: 3 * cospi
|
|
vqdmulh.s16 q8, q5, d0[2] ; sinpi8sqrt2
|
|
vqdmulh.s16 q9, q7, d0[2]
|
|
vqdmulh.s16 q10, q5, d0[0] ; cospi8sqrt2minus1
|
|
vqdmulh.s16 q11, q7, d0[0]
|
|
|
|
vqadd.s16 q2, q4, q6 ; a1 = 0 + 2
|
|
vqsub.s16 q3, q4, q6 ; b1 = 0 - 2
|
|
|
|
; see note on shifting above
|
|
vshr.s16 q10, q10, #1
|
|
vshr.s16 q11, q11, #1
|
|
|
|
; q10: 1 + 1 * cospi : d1/temp1
|
|
; q11: 3 + 3 * cospi : c1/temp2
|
|
vqadd.s16 q10, q5, q10
|
|
vqadd.s16 q11, q7, q11
|
|
|
|
; q8: c1 = temp1 - temp2
|
|
; q9: d1 = temp1 + temp2
|
|
vqsub.s16 q8, q8, q11
|
|
vqadd.s16 q9, q10, q9
|
|
|
|
; a1+d1
|
|
; b1+c1
|
|
; b1-c1
|
|
; a1-d1
|
|
vqadd.s16 q4, q2, q9
|
|
vqadd.s16 q5, q3, q8
|
|
vqsub.s16 q6, q3, q8
|
|
vqsub.s16 q7, q2, q9
|
|
|
|
; +4 >> 3 (rounding)
|
|
vrshr.s16 q4, q4, #3 ; lo
|
|
vrshr.s16 q5, q5, #3
|
|
vrshr.s16 q6, q6, #3 ; hi
|
|
vrshr.s16 q7, q7, #3
|
|
|
|
vtrn.32 q4, q6
|
|
vtrn.32 q5, q7
|
|
vtrn.16 q4, q5
|
|
vtrn.16 q6, q7
|
|
|
|
; adding pre
|
|
; input is still packed. pre was read interleaved
|
|
vaddw.u8 q4, q4, d28
|
|
vaddw.u8 q5, q5, d29
|
|
vaddw.u8 q6, q6, d30
|
|
vaddw.u8 q7, q7, d31
|
|
|
|
vmov.i16 q14, #0
|
|
vmov q15, q14
|
|
vst1.16 {q14, q15}, [r0] ; write over high input
|
|
sub r0, r0, #32
|
|
vst1.16 {q14, q15}, [r0] ; write over low input
|
|
|
|
;saturate and narrow
|
|
vqmovun.s16 d0, q4 ; lo
|
|
vqmovun.s16 d1, q5
|
|
vqmovun.s16 d2, q6 ; hi
|
|
vqmovun.s16 d3, q7
|
|
|
|
ldr r1, [sp, #4] ; stride
|
|
add r2, r3, #4 ; hi
|
|
vst1.32 {d0[0]}, [r3], r1 ; lo
|
|
vst1.32 {d0[1]}, [r2], r1 ; hi
|
|
vst1.32 {d1[0]}, [r3], r1
|
|
vst1.32 {d1[1]}, [r2], r1
|
|
vst1.32 {d2[0]}, [r3], r1
|
|
vst1.32 {d2[1]}, [r2], r1
|
|
vst1.32 {d3[0]}, [r3]
|
|
vst1.32 {d3[1]}, [r2]
|
|
|
|
bx lr
|
|
|
|
ENDP ; |idct_dequant_full_2x_neon|
|
|
|
|
; Constant Pool
|
|
cospi8sqrt2minus1 DCD 0x4e7b
|
|
; because the lowest bit in 0x8a8c is 0, we can pre-shift this
|
|
sinpi8sqrt2 DCD 0x4546
|
|
|
|
END
|