ref: bf43b4c4b47eff60e52e9d036de8618b4a1fece1
dir: /vpx_dsp/arm/idct4x4_1_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 |vpx_idct4x4_1_add_neon|
ARM
REQUIRE8
PRESERVE8
AREA ||.text||, CODE, READONLY, ALIGN=2
;void vpx_idct4x4_1_add_neon(int16_t *input, uint8_t *dest, int stride)
;
; r0 int16_t input
; r1 uint8_t *dest
; r2 int stride)
|vpx_idct4x4_1_add_neon| PROC
ldrsh r0, [r0]
; cospi_16_64 = 11585
movw r12, #0x2d41
; out = dct_const_round_shift(input[0] * cospi_16_64)
mul r0, r0, r12 ; input[0] * cospi_16_64
add r0, r0, #0x2000 ; +(1 << ((DCT_CONST_BITS) - 1))
asr r0, r0, #14 ; >> DCT_CONST_BITS
; out = dct_const_round_shift(out * cospi_16_64)
mul r0, r0, r12 ; out * cospi_16_64
mov r12, r1 ; save dest
add r0, r0, #0x2000 ; +(1 << ((DCT_CONST_BITS) - 1))
asr r0, r0, #14 ; >> DCT_CONST_BITS
; a1 = ROUND_POWER_OF_TWO(out, 4)
add r0, r0, #8 ; + (1 <<((4) - 1))
asr r0, r0, #4 ; >> 4
vdup.s16 q0, r0 ; duplicate a1
vld1.32 {d2[0]}, [r1], r2
vld1.32 {d2[1]}, [r1], r2
vld1.32 {d4[0]}, [r1], r2
vld1.32 {d4[1]}, [r1]
vaddw.u8 q8, q0, d2 ; dest[x] + a1
vaddw.u8 q9, q0, d4
vqmovun.s16 d6, q8 ; clip_pixel
vqmovun.s16 d7, q9
vst1.32 {d6[0]}, [r12], r2
vst1.32 {d6[1]}, [r12], r2
vst1.32 {d7[0]}, [r12], r2
vst1.32 {d7[1]}, [r12]
bx lr
ENDP ; |vpx_idct4x4_1_add_neon|
END