ref: c7cfe7a9eebd7d0940edacd1b8649343ed477e47
dir: /vp9/common/arm/neon/vp9_dc_only_idct_add_neon.asm/
;
; Copyright (c) 2013 The WebM project authors. All Rights Reserved.
;
; Use of this source code is governed by a BSD-style license and patent
; grant that can be found in the LICENSE file in the root of the source
; tree. All contributing project authors may be found in the AUTHORS
; file in the root of the source tree.
;
EXPORT |vp9_dc_only_idct_add_neon|
ARM
REQUIRE8
PRESERVE8
AREA ||.text||, CODE, READONLY, ALIGN=2
;void vp9_dc_only_idct_add_neon(int input_dc, uint8_t *pred_ptr,
; uint8_t *dst_ptr, int pitch, int stride)
;
; r0 int input_dc
; r1 uint8_t *pred_ptr
; r2 uint8_t *dst_ptr
; r3 int pitch
; sp int stride
|vp9_dc_only_idct_add_neon| PROC
; generate cospi_16_64 = 11585
mov r12, #0x2d00
add r12, #0x41
; dct_const_round_shift(input_dc * cospi_16_64)
mul r0, r0, r12 ; input_dc * cospi_16_64
add r0, r0, #0x2000 ; +(1 << ((DCT_CONST_BITS) - 1))
asr r0, r0, #14 ; >> DCT_CONST_BITS
; dct_const_round_shift(out * cospi_16_64)
mul r0, r0, r12 ; out * cospi_16_64
add r0, r0, #0x2000 ; +(1 << ((DCT_CONST_BITS) - 1))
asr r0, r0, #14 ; >> DCT_CONST_BITS
; ROUND_POWER_OF_TWO(out, 4)
add r0, r0, #8 ; + (1 <<((4) - 1))
asr r0, r0, #4 ; >> 4
vdup.16 q0, r0; ; duplicate a1
ldr r12, [sp] ; load stride
vld1.32 {d2[0]}, [r1], r3
vld1.32 {d2[1]}, [r1], r3
vld1.32 {d4[0]}, [r1], r3
vld1.32 {d4[1]}, [r1]
vaddw.u8 q1, q0, d2 ; a1 + pred_ptr[c]
vaddw.u8 q2, q0, d4
vqmovun.s16 d2, q1 ; clip_pixel
vqmovun.s16 d4, q2
vst1.32 {d2[0]}, [r2], r12
vst1.32 {d2[1]}, [r2], r12
vst1.32 {d4[0]}, [r2], r12
vst1.32 {d4[1]}, [r2]
bx lr
ENDP ; |vp9_dc_only_idct_add_neon|
END