1 ; 2 ; Copyright (c) 2011 The WebM project authors. All Rights Reserved. 3 ; 4 ; Use of this source code is governed by a BSD-style license 5 ; that can be found in the LICENSE file in the root of the source 6 ; tree. An additional intellectual property rights grant can be found 7 ; in the file PATENTS. All contributing project authors may 8 ; be found in the AUTHORS file in the root of the source tree. 9 ; 10 11 12 EXPORT |vp8_variance_halfpixvar16x16_v_armv6| 13 14 ARM 15 REQUIRE8 16 PRESERVE8 17 18 AREA ||.text||, CODE, READONLY, ALIGN=2 19 20 ; r0 unsigned char *src_ptr 21 ; r1 int source_stride 22 ; r2 unsigned char *ref_ptr 23 ; r3 int recon_stride 24 ; stack unsigned int *sse 25 |vp8_variance_halfpixvar16x16_v_armv6| PROC 26 27 stmfd sp!, {r4-r12, lr} 28 29 pld [r0, r1, lsl #0] 30 pld [r2, r3, lsl #0] 31 32 mov r8, #0 ; initialize sum = 0 33 ldr r10, c80808080 34 mov r11, #0 ; initialize sse = 0 35 mov r12, #16 ; set loop counter to 16 (=block height) 36 mov lr, #0 ; constant zero 37 loop 38 add r9, r0, r1 ; set src pointer to next row 39 ; 1st 4 pixels 40 ldr r4, [r0, #0] ; load 4 src pixels 41 ldr r6, [r9, #0] ; load 4 src pixels from next row 42 ldr r5, [r2, #0] ; load 4 ref pixels 43 44 ; bilinear interpolation 45 mvn r6, r6 46 uhsub8 r4, r4, r6 47 eor r4, r4, r10 48 49 usub8 r6, r4, r5 ; calculate difference 50 pld [r0, r1, lsl #1] 51 sel r7, r6, lr ; select bytes with positive difference 52 usub8 r6, r5, r4 ; calculate difference with reversed operands 53 pld [r2, r3, lsl #1] 54 sel r6, r6, lr ; select bytes with negative difference 55 56 ; calculate partial sums 57 usad8 r4, r7, lr ; calculate sum of positive differences 58 usad8 r5, r6, lr ; calculate sum of negative differences 59 orr r6, r6, r7 ; differences of all 4 pixels 60 ; calculate total sum 61 adds r8, r8, r4 ; add positive differences to sum 62 subs r8, r8, r5 ; subtract negative differences from sum 63 64 ; calculate sse 65 uxtb16 r5, r6 ; byte (two pixels) to halfwords 66 uxtb16 r7, r6, ror #8 ; another two pixels to halfwords 67 smlad r11, r5, r5, r11 ; dual signed multiply, add and accumulate (1) 68 69 ; 2nd 4 pixels 70 ldr r4, [r0, #4] ; load 4 src pixels 71 ldr r6, [r9, #4] ; load 4 src pixels from next row 72 ldr r5, [r2, #4] ; load 4 ref pixels 73 74 ; bilinear interpolation 75 mvn r6, r6 76 uhsub8 r4, r4, r6 77 eor r4, r4, r10 78 79 smlad r11, r7, r7, r11 ; dual signed multiply, add and accumulate (2) 80 81 usub8 r6, r4, r5 ; calculate difference 82 sel r7, r6, lr ; select bytes with positive difference 83 usub8 r6, r5, r4 ; calculate difference with reversed operands 84 sel r6, r6, lr ; select bytes with negative difference 85 86 ; calculate partial sums 87 usad8 r4, r7, lr ; calculate sum of positive differences 88 usad8 r5, r6, lr ; calculate sum of negative differences 89 orr r6, r6, r7 ; differences of all 4 pixels 90 91 ; calculate total sum 92 add r8, r8, r4 ; add positive differences to sum 93 sub r8, r8, r5 ; subtract negative differences from sum 94 95 ; calculate sse 96 uxtb16 r5, r6 ; byte (two pixels) to halfwords 97 uxtb16 r7, r6, ror #8 ; another two pixels to halfwords 98 smlad r11, r5, r5, r11 ; dual signed multiply, add and accumulate (1) 99 100 ; 3rd 4 pixels 101 ldr r4, [r0, #8] ; load 4 src pixels 102 ldr r6, [r9, #8] ; load 4 src pixels from next row 103 ldr r5, [r2, #8] ; load 4 ref pixels 104 105 ; bilinear interpolation 106 mvn r6, r6 107 uhsub8 r4, r4, r6 108 eor r4, r4, r10 109 110 smlad r11, r7, r7, r11 ; dual signed multiply, add and accumulate (2) 111 112 usub8 r6, r4, r5 ; calculate difference 113 sel r7, r6, lr ; select bytes with positive difference 114 usub8 r6, r5, r4 ; calculate difference with reversed operands 115 sel r6, r6, lr ; select bytes with negative difference 116 117 ; calculate partial sums 118 usad8 r4, r7, lr ; calculate sum of positive differences 119 usad8 r5, r6, lr ; calculate sum of negative differences 120 orr r6, r6, r7 ; differences of all 4 pixels 121 122 ; calculate total sum 123 add r8, r8, r4 ; add positive differences to sum 124 sub r8, r8, r5 ; subtract negative differences from sum 125 126 ; calculate sse 127 uxtb16 r5, r6 ; byte (two pixels) to halfwords 128 uxtb16 r7, r6, ror #8 ; another two pixels to halfwords 129 smlad r11, r5, r5, r11 ; dual signed multiply, add and accumulate (1) 130 131 ; 4th 4 pixels 132 ldr r4, [r0, #12] ; load 4 src pixels 133 ldr r6, [r9, #12] ; load 4 src pixels from next row 134 ldr r5, [r2, #12] ; load 4 ref pixels 135 136 ; bilinear interpolation 137 mvn r6, r6 138 uhsub8 r4, r4, r6 139 eor r4, r4, r10 140 141 smlad r11, r7, r7, r11 ; dual signed multiply, add and accumulate (2) 142 143 usub8 r6, r4, r5 ; calculate difference 144 add r0, r0, r1 ; set src_ptr to next row 145 sel r7, r6, lr ; select bytes with positive difference 146 usub8 r6, r5, r4 ; calculate difference with reversed operands 147 add r2, r2, r3 ; set dst_ptr to next row 148 sel r6, r6, lr ; select bytes with negative difference 149 150 ; calculate partial sums 151 usad8 r4, r7, lr ; calculate sum of positive differences 152 usad8 r5, r6, lr ; calculate sum of negative differences 153 orr r6, r6, r7 ; differences of all 4 pixels 154 155 ; calculate total sum 156 add r8, r8, r4 ; add positive differences to sum 157 sub r8, r8, r5 ; subtract negative differences from sum 158 159 ; calculate sse 160 uxtb16 r5, r6 ; byte (two pixels) to halfwords 161 uxtb16 r7, r6, ror #8 ; another two pixels to halfwords 162 smlad r11, r5, r5, r11 ; dual signed multiply, add and accumulate (1) 163 smlad r11, r7, r7, r11 ; dual signed multiply, add and accumulate (2) 164 165 166 subs r12, r12, #1 167 168 bne loop 169 170 ; return stuff 171 ldr r6, [sp, #40] ; get address of sse 172 mul r0, r8, r8 ; sum * sum 173 str r11, [r6] ; store sse 174 sub r0, r11, r0, lsr #8 ; return (sse - ((sum * sum) >> 8)) 175 176 ldmfd sp!, {r4-r12, pc} 177 178 ENDP 179 180 c80808080 181 DCD 0x80808080 182 183 END 184 185
