ref: d5b8f7860f17ad5c37bd5f6e9e73d548c80817ab
dir: /vp8/common/arm/neon/loopfiltersimplehorizontaledge_neon.asm/
;
; 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 |vp8_loop_filter_simple_horizontal_edge_neon|
ARM
REQUIRE8
PRESERVE8
AREA ||.text||, CODE, READONLY, ALIGN=2
;Note: flimit, limit, and thresh shpuld be positive numbers. All 16 elements in flimit
;are equal. So, in the code, only one load is needed
;for flimit. Same way applies to limit and thresh.
; r0 unsigned char *s,
; r1 int p, //pitch
; r2 const signed char *flimit,
; r3 const signed char *limit,
; stack(r4) const signed char *thresh (unused)
; //stack(r5) int count --unused
|vp8_loop_filter_simple_horizontal_edge_neon| PROC
sub r0, r0, r1, lsl #1 ; move src pointer down by 2 lines
vld1.u8 {q5}, [r0], r1 ; p1
vld1.s8 {d2[], d3[]}, [r2] ; flimit
vld1.s8 {d26[], d27[]}, [r3] ; limit -> q13
vld1.u8 {q6}, [r0], r1 ; p0
vmov.u8 q0, #0x80 ; 0x80
vld1.u8 {q7}, [r0], r1 ; q0
vmov.u8 q10, #0x03 ; 0x03
vld1.u8 {q8}, [r0] ; q1
;vp8_filter_mask() function
vabd.u8 q15, q6, q7 ; abs(p0 - q0)
vabd.u8 q14, q5, q8 ; abs(p1 - q1)
vqadd.u8 q15, q15, q15 ; abs(p0 - q0) * 2
vshr.u8 q14, q14, #1 ; abs(p1 - q1) / 2
vqadd.u8 q15, q15, q14 ; abs(p0 - q0) * 2 + abs(p1 - q1) / 2
;vp8_filter() function
veor q7, q7, q0 ; qs0: q0 offset to convert to a signed value
veor q6, q6, q0 ; ps0: p0 offset to convert to a signed value
veor q5, q5, q0 ; ps1: p1 offset to convert to a signed value
veor q8, q8, q0 ; qs1: q1 offset to convert to a signed value
vadd.u8 q1, q1, q1 ; flimit * 2
vadd.u8 q1, q1, q13 ; flimit * 2 + limit
vcge.u8 q15, q1, q15 ; (abs(p0 - q0)*2 + abs(p1-q1)/2 > flimit*2 + limit)*-1
;;;;;;;;;;
;vqsub.s8 q2, q7, q6 ; ( qs0 - ps0)
vsubl.s8 q2, d14, d12 ; ( qs0 - ps0)
vsubl.s8 q3, d15, d13
vqsub.s8 q4, q5, q8 ; q4: vp8_filter = vp8_signed_char_clamp(ps1-qs1)
;vmul.i8 q2, q2, q10 ; 3 * ( qs0 - ps0)
vadd.s16 q11, q2, q2 ; 3 * ( qs0 - ps0)
vadd.s16 q12, q3, q3
vmov.u8 q9, #0x04 ; 0x04
vadd.s16 q2, q2, q11
vadd.s16 q3, q3, q12
vaddw.s8 q2, q2, d8 ; vp8_filter + 3 * ( qs0 - ps0)
vaddw.s8 q3, q3, d9
;vqadd.s8 q4, q4, q2 ; vp8_filter = vp8_signed_char_clamp(vp8_filter + 3 * ( qs0 - ps0))
vqmovn.s16 d8, q2 ; vp8_filter = vp8_signed_char_clamp(vp8_filter + 3 * ( qs0 - ps0))
vqmovn.s16 d9, q3
;;;;;;;;;;;;;
vand q4, q4, q15 ; vp8_filter &= mask
vqadd.s8 q2, q4, q10 ; Filter2 = vp8_signed_char_clamp(vp8_filter+3)
vqadd.s8 q4, q4, q9 ; Filter1 = vp8_signed_char_clamp(vp8_filter+4)
vshr.s8 q2, q2, #3 ; Filter2 >>= 3
vshr.s8 q4, q4, #3 ; Filter1 >>= 3
sub r0, r0, r1, lsl #1
;calculate output
vqadd.s8 q11, q6, q2 ; u = vp8_signed_char_clamp(ps0 + Filter2)
vqsub.s8 q10, q7, q4 ; u = vp8_signed_char_clamp(qs0 - Filter1)
add r3, r0, r1
veor q6, q11, q0 ; *op0 = u^0x80
veor q7, q10, q0 ; *oq0 = u^0x80
vst1.u8 {q6}, [r0] ; store op0
vst1.u8 {q7}, [r3] ; store oq0
bx lr
ENDP ; |vp8_loop_filter_simple_horizontal_edge_neon|
;-----------------
END