; ; Copyright (c) 2011 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_short_fdct4x4_armv6| ARM REQUIRE8 PRESERVE8 AREA |.text|, CODE, READONLY ; void vp8_short_fdct4x4_c(short *input, short *output, int pitch) |vp8_short_fdct4x4_armv6| PROC stmfd sp!, {r4 - r12, lr} ; PART 1 ; coeffs 0-3 ldrd r4, r5, [r0] ; [i1 | i0] [i3 | i2] ldr r10, c7500 ldr r11, c14500 ldr r12, c0x22a453a0 ; [2217*4 | 5352*4] ldr lr, c0x00080008 ror r5, r5, #16 ; [i2 | i3] qadd16 r6, r4, r5 ; [i1+i2 | i0+i3] = [b1 | a1] without shift qsub16 r7, r4, r5 ; [i1-i2 | i0-i3] = [c1 | d1] without shift add r0, r0, r2 ; update input pointer qadd16 r7, r7, r7 ; 2*[c1|d1] --> we can use smlad and smlsd ; with 2217*4 and 5352*4 without losing the ; sign bit (overflow) smuad r4, r6, lr ; o0 = (i1+i2)*8 + (i0+i3)*8 smusd r5, r6, lr ; o2 = (i1+i2)*8 - (i0+i3)*8 smlad r6, r7, r12, r11 ; o1 = (c1 * 2217 + d1 * 5352 + 14500) smlsdx r7, r7, r12, r10 ; o3 = (d1 * 2217 - c1 * 5352 + 7500) ldrd r8, r9, [r0] ; [i5 | i4] [i7 | i6] pkhbt r3, r4, r6, lsl #4 ; [o1 | o0], keep in register for PART 2 pkhbt r6, r5, r7, lsl #4 ; [o3 | o2] str r6, [r1, #4] ; coeffs 4-7 ror r9, r9, #16 ; [i6 | i7] qadd16 r6, r8, r9 ; [i5+i6 | i4+i7] = [b1 | a1] without shift qsub16 r7, r8, r9 ; [i5-i6 | i4-i7] = [c1 | d1] without shift add r0, r0, r2 ; update input pointer qadd16 r7, r7, r7 ; 2x[c1|d1] --> we can use smlad and smlsd ; with 2217*4 and 5352*4 without losing the ; sign bit (overflow) smuad r9, r6, lr ; o4 = (i5+i6)*8 + (i4+i7)*8 smusd r8, r6, lr ; o6 = (i5+i6)*8 - (i4+i7)*8 smlad r6, r7, r12, r11 ; o5 = (c1 * 2217 + d1 * 5352 + 14500) smlsdx r7, r7, r12, r10 ; o7 = (d1 * 2217 - c1 * 5352 + 7500) ldrd r4, r5, [r0] ; [i9 | i8] [i11 | i10] pkhbt r9, r9, r6, lsl #4 ; [o5 | o4], keep in register for PART 2 pkhbt r6, r8, r7, lsl #4 ; [o7 | o6] str r6, [r1, #12] ; coeffs 8-11 ror r5, r5, #16 ; [i10 | i11] qadd16 r6, r4, r5 ; [i9+i10 | i8+i11]=[b1 | a1] without shift qsub16 r7, r4, r5 ; [i9-i10 | i8-i11]=[c1 | d1] without shift add r0, r0, r2 ; update input pointer qadd16 r7, r7, r7 ; 2x[c1|d1] --> we can use smlad and smlsd ; with 2217*4 and 5352*4 without losing the ; sign bit (overflow) smuad r2, r6, lr ; o8 = (i9+i10)*8 + (i8+i11)*8 smusd r8, r6, lr ; o10 = (i9+i10)*8 - (i8+i11)*8 smlad r6, r7, r12, r11 ; o9 = (c1 * 2217 + d1 * 5352 + 14500) smlsdx r7, r7, r12, r10 ; o11 = (d1 * 2217 - c1 * 5352 + 7500) ldrd r4, r5, [r0] ; [i13 | i12] [i15 | i14] pkhbt r2, r2, r6, lsl #4 ; [o9 | o8], keep in register for PART 2 pkhbt r6, r8, r7, lsl #4 ; [o11 | o10] str r6, [r1, #20] ; coeffs 12-15 ror r5, r5, #16 ; [i14 | i15] qadd16 r6, r4, r5 ; [i13+i14 | i12+i15]=[b1|a1] without shift qsub16 r7, r4, r5 ; [i13-i14 | i12-i15]=[c1|d1] without shift qadd16 r7, r7, r7 ; 2x[c1|d1] --> we can use smlad and smlsd ; with 2217*4 and 5352*4 without losing the ; sign bit (overflow) smuad r4, r6, lr ; o12 = (i13+i14)*8 + (i12+i15)*8 smusd r5, r6, lr ; o14 = (i13+i14)*8 - (i12+i15)*8 smlad r6, r7, r12, r11 ; o13 = (c1 * 2217 + d1 * 5352 + 14500) smlsdx r7, r7, r12, r10 ; o15 = (d1 * 2217 - c1 * 5352 + 7500) pkhbt r0, r4, r6, lsl #4 ; [o13 | o12], keep in register for PART 2 pkhbt r6, r5, r7, lsl #4 ; [o15 | o14] str r6, [r1, #28] ; PART 2 ------------------------------------------------- ldr r11, c12000 ldr r10, c51000 ldr lr, c0x00070007 qadd16 r4, r3, r0 ; a1 = [i1+i13 | i0+i12] qadd16 r5, r9, r2 ; b1 = [i5+i9 | i4+i8] qsub16 r6, r9, r2 ; c1 = [i5-i9 | i4-i8] qsub16 r7, r3, r0 ; d1 = [i1-i13 | i0-i12] qadd16 r4, r4, lr ; a1 + 7 add r0, r11, #0x10000 ; add (d!=0) qadd16 r2, r4, r5 ; a1 + b1 + 7 qsub16 r3, r4, r5 ; a1 - b1 + 7 ldr r12, c0x08a914e8 ; [2217 | 5352] lsl r8, r2, #16 ; prepare bottom halfword for scaling asr r2, r2, #4 ; scale top halfword lsl r9, r3, #16 ; prepare bottom halfword for scaling asr r3, r3, #4 ; scale top halfword pkhtb r4, r2, r8, asr #20 ; pack and scale bottom halfword pkhtb r5, r3, r9, asr #20 ; pack and scale bottom halfword smulbt r2, r6, r12 ; [ ------ | c1*2217] str r4, [r1, #0] ; [ o1 | o0] smultt r3, r6, r12 ; [c1*2217 | ------ ] str r5, [r1, #16] ; [ o9 | o8] smlabb r8, r7, r12, r2 ; [ ------ | d1*5352] smlatb r9, r7, r12, r3 ; [d1*5352 | ------ ] smulbb r2, r6, r12 ; [ ------ | c1*5352] smultb r3, r6, r12 ; [c1*5352 | ------ ] lsls r6, r7, #16 ; d1 != 0 ? addeq r8, r8, r11 ; c1_b*2217+d1_b*5352+12000 + (d==0) addne r8, r8, r0 ; c1_b*2217+d1_b*5352+12000 + (d!=0) asrs r6, r7, #16 addeq r9, r9, r11 ; c1_t*2217+d1_t*5352+12000 + (d==0) addne r9, r9, r0 ; c1_t*2217+d1_t*5352+12000 + (d!=0) smlabt r4, r7, r12, r10 ; [ ------ | d1*2217] + 51000 smlatt r5, r7, r12, r10 ; [d1*2217 | ------ ] + 51000 pkhtb r9, r9, r8, asr #16 sub r4, r4, r2 sub r5, r5, r3 ldr r3, [r1, #4] ; [i3 | i2] pkhtb r5, r5, r4, asr #16 ; [o13|o12] str r9, [r1, #8] ; [o5 | 04] ldr r9, [r1, #12] ; [i7 | i6] ldr r8, [r1, #28] ; [i15|i14] ldr r2, [r1, #20] ; [i11|i10] str r5, [r1, #24] ; [o13|o12] qadd16 r4, r3, r8 ; a1 = [i3+i15 | i2+i14] qadd16 r5, r9, r2 ; b1 = [i7+i11 | i6+i10] qadd16 r4, r4, lr ; a1 + 7 qsub16 r6, r9, r2 ; c1 = [i7-i11 | i6-i10] qadd16 r2, r4, r5 ; a1 + b1 + 7 qsub16 r7, r3, r8 ; d1 = [i3-i15 | i2-i14] qsub16 r3, r4, r5 ; a1 - b1 + 7 lsl r8, r2, #16 ; prepare bottom halfword for scaling asr r2, r2, #4 ; scale top halfword lsl r9, r3, #16 ; prepare bottom halfword for scaling asr r3, r3, #4 ; scale top halfword pkhtb r4, r2, r8, asr #20 ; pack and scale bottom halfword pkhtb r5, r3, r9, asr #20 ; pack and scale bottom halfword smulbt r2, r6, r12 ; [ ------ | c1*2217] str r4, [r1, #4] ; [ o3 | o2] smultt r3, r6, r12 ; [c1*2217 | ------ ] str r5, [r1, #20] ; [ o11 | o10] smlabb r8, r7, r12, r2 ; [ ------ | d1*5352] smlatb r9, r7, r12, r3 ; [d1*5352 | ------ ] smulbb r2, r6, r12 ; [ ------ | c1*5352] smultb r3, r6, r12 ; [c1*5352 | ------ ] lsls r6, r7, #16 ; d1 != 0 ? addeq r8, r8, r11 ; c1_b*2217+d1_b*5352+12000 + (d==0) addne r8, r8, r0 ; c1_b*2217+d1_b*5352+12000 + (d!=0) asrs r6, r7, #16 addeq r9, r9, r11 ; c1_t*2217+d1_t*5352+12000 + (d==0) addne r9, r9, r0 ; c1_t*2217+d1_t*5352+12000 + (d!=0) smlabt r4, r7, r12, r10 ; [ ------ | d1*2217] + 51000 smlatt r5, r7, r12, r10 ; [d1*2217 | ------ ] + 51000 pkhtb r9, r9, r8, asr #16 sub r4, r4, r2 sub r5, r5, r3 str r9, [r1, #12] ; [o7 | o6] pkhtb r5, r5, r4, asr #16 ; [o15|o14] str r5, [r1, #28] ; [o15|o14] ldmfd sp!, {r4 - r12, pc} ENDP ; Used constants c7500 DCD 7500 c14500 DCD 14500 c0x22a453a0 DCD 0x22a453a0 c0x00080008 DCD 0x00080008 c12000 DCD 12000 c51000 DCD 51000 c0x00070007 DCD 0x00070007 c0x08a914e8 DCD 0x08a914e8 END