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_h_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_h_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 ; 1st 4 pixels 39 ldr r4, [r0, #0] ; load 4 src pixels 40 ldr r6, [r0, #1] ; load 4 src pixels with 1 byte offset 41 ldr r5, [r2, #0] ; load 4 ref pixels 42 43 ; bilinear interpolation 44 mvn r6, r6 45 uhsub8 r4, r4, r6 46 eor r4, r4, r10 47 48 usub8 r6, r4, r5 ; calculate difference 49 pld [r0, r1, lsl #1] 50 sel r7, r6, lr ; select bytes with positive difference 51 usub8 r6, r5, r4 ; calculate difference with reversed operands 52 pld [r2, r3, lsl #1] 53 sel r6, r6, lr ; select bytes with negative difference 54 55 ; calculate partial sums 56 usad8 r4, r7, lr ; calculate sum of positive differences 57 usad8 r5, r6, lr ; calculate sum of negative differences 58 orr r6, r6, r7 ; differences of all 4 pixels 59 ; calculate total sum 60 adds r8, r8, r4 ; add positive differences to sum 61 subs r8, r8, r5 ; subtract negative differences from sum 62 63 ; calculate sse 64 uxtb16 r5, r6 ; byte (two pixels) to halfwords 65 uxtb16 r7, r6, ror #8 ; another two pixels to halfwords 66 smlad r11, r5, r5, r11 ; dual signed multiply, add and accumulate (1) 67 68 ; 2nd 4 pixels 69 ldr r4, [r0, #4] ; load 4 src pixels 70 ldr r6, [r0, #5] ; load 4 src pixels with 1 byte offset 71 ldr r5, [r2, #4] ; load 4 ref pixels 72 73 ; bilinear interpolation 74 mvn r6, r6 75 uhsub8 r4, r4, r6 76 eor r4, r4, r10 77 78 smlad r11, r7, r7, r11 ; dual signed multiply, add and accumulate (2) 79 80 usub8 r6, r4, r5 ; calculate difference 81 sel r7, r6, lr ; select bytes with positive difference 82 usub8 r6, r5, r4 ; calculate difference with reversed operands 83 sel r6, r6, lr ; select bytes with negative difference 84 85 ; calculate partial sums 86 usad8 r4, r7, lr ; calculate sum of positive differences 87 usad8 r5, r6, lr ; calculate sum of negative differences 88 orr r6, r6, r7 ; differences of all 4 pixels 89 90 ; calculate total sum 91 add r8, r8, r4 ; add positive differences to sum 92 sub r8, r8, r5 ; subtract negative differences from sum 93 94 ; calculate sse 95 uxtb16 r5, r6 ; byte (two pixels) to halfwords 96 uxtb16 r7, r6, ror #8 ; another two pixels to halfwords 97 smlad r11, r5, r5, r11 ; dual signed multiply, add and accumulate (1) 98 99 ; 3rd 4 pixels 100 ldr r4, [r0, #8] ; load 4 src pixels 101 ldr r6, [r0, #9] ; load 4 src pixels with 1 byte offset 102 ldr r5, [r2, #8] ; load 4 ref pixels 103 104 ; bilinear interpolation 105 mvn r6, r6 106 uhsub8 r4, r4, r6 107 eor r4, r4, r10 108 109 smlad r11, r7, r7, r11 ; dual signed multiply, add and accumulate (2) 110 111 usub8 r6, r4, r5 ; calculate difference 112 sel r7, r6, lr ; select bytes with positive difference 113 usub8 r6, r5, r4 ; calculate difference with reversed operands 114 sel r6, r6, lr ; select bytes with negative difference 115 116 ; calculate partial sums 117 usad8 r4, r7, lr ; calculate sum of positive differences 118 usad8 r5, r6, lr ; calculate sum of negative differences 119 orr r6, r6, r7 ; differences of all 4 pixels 120 121 ; calculate total sum 122 add r8, r8, r4 ; add positive differences to sum 123 sub r8, r8, r5 ; subtract negative differences from sum 124 125 ; calculate sse 126 uxtb16 r5, r6 ; byte (two pixels) to halfwords 127 uxtb16 r7, r6, ror #8 ; another two pixels to halfwords 128 smlad r11, r5, r5, r11 ; dual signed multiply, add and accumulate (1) 129 130 ; 4th 4 pixels 131 ldr r4, [r0, #12] ; load 4 src pixels 132 ldr r6, [r0, #13] ; load 4 src pixels with 1 byte offset 133 ldr r5, [r2, #12] ; load 4 ref pixels 134 135 ; bilinear interpolation 136 mvn r6, r6 137 uhsub8 r4, r4, r6 138 eor r4, r4, r10 139 140 smlad r11, r7, r7, r11 ; dual signed multiply, add and accumulate (2) 141 142 usub8 r6, r4, r5 ; calculate difference 143 add r0, r0, r1 ; set src_ptr to next row 144 sel r7, r6, lr ; select bytes with positive difference 145 usub8 r6, r5, r4 ; calculate difference with reversed operands 146 add r2, r2, r3 ; set dst_ptr to next row 147 sel r6, r6, lr ; select bytes with negative difference 148 149 ; calculate partial sums 150 usad8 r4, r7, lr ; calculate sum of positive differences 151 usad8 r5, r6, lr ; calculate sum of negative differences 152 orr r6, r6, r7 ; differences of all 4 pixels 153 154 ; calculate total sum 155 add r8, r8, r4 ; add positive differences to sum 156 sub r8, r8, r5 ; subtract negative differences from sum 157 158 ; calculate sse 159 uxtb16 r5, r6 ; byte (two pixels) to halfwords 160 uxtb16 r7, r6, ror #8 ; another two pixels to halfwords 161 smlad r11, r5, r5, r11 ; dual signed multiply, add and accumulate (1) 162 smlad r11, r7, r7, r11 ; dual signed multiply, add and accumulate (2) 163 164 subs r12, r12, #1 165 166 bne loop 167 168 ; return stuff 169 ldr r6, [sp, #40] ; get address of sse 170 mul r0, r8, r8 ; sum * sum 171 str r11, [r6] ; store sse 172 sub r0, r11, r0, lsr #8 ; return (sse - ((sum * sum) >> 8)) 173 174 ldmfd sp!, {r4-r12, pc} 175 176 ENDP 177 178 c80808080 179 DCD 0x80808080 180 181 END 182 183
