/*

* Copyright (C) 2008 The Android Open Source Project

*

* Licensed under the Apache License, Version 2.0 (the "License");

* you may not use this file except in compliance with the License.

* You may obtain a copy of the License at

*

* http://www.apache.org/licenses/LICENSE-2.0

*

* Unless required by applicable law or agreed to in writing, software

* distributed under the License is distributed on an "AS IS" BASIS,

* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

* See the License for the specific language governing permissions and

* limitations under the License.

*/

#include <machine/cpu-features.h>

.text

.align

.global jpeg_idct_ifast

.func jpeg_idct_ifast

// NOTE: sb=r9, fp=r11 ip=r12, sp=r13, lr=r14, pc=r15

// jpeg_idct_ifast (j_decompress_ptr cinfo,

// jpeg_component_info * compptr,

// short* coef_block,

// unsigned char* output_buf,

// int output_col)

#define local_TMP0123 sp

#define local_TMP0 [sp, #0]

#define local_TMP1 [sp, #4]

#define local_TMP2 [sp, #8]

#define local_TMP3 [sp, #12]

#define local_RANGE_TABLE [sp, #16]

#define local_OUTPUT_COL [sp, #20]

#define local_OUTPUT_BUF [sp, #24]

#define local_UNUSED [sp, #28]

#define off_WORKSPACE 32

#define local_WORKSPACE [sp, #offWORKSPACE]

#define local_SIZE (off_WORKSPACE + 8*8*4)

#define off_DECOMPRESS_range_limit_base 324

#define off_COMPINFO_quanttable 80

#define DCTSIZE 8

#define VY(x) ((x)*DCTSIZE*2)

#define QY(x) ((x)*DCTSIZE*4)

#define VX(x) ((x)*2)

#define QX(x) ((x)*4)

#define FIX_1_414213562 #362

#define FIX_1_082392200 #277

#define FIX_1_847759065 #473

#define FIX_2_613125930 #669

#define RANGE_MASK 1023

jpeg_idct_ifast:

PLD [r2, #0]

stmdb sp!, {r4,r5, r6,r7, r8,r9, r10,r11, r12,lr}

ldr r4, [sp, #4*10]

sub sp, #local_SIZE

ldr r10,[r1, #off_COMPINFO_quanttable] // r10 = quanttable

str r4, local_OUTPUT_COL

str r3, local_OUTPUT_BUF

ldr r5, [r0, #off_DECOMPRESS_range_limit_base]

add r5, r5, #128

str r5, local_RANGE_TABLE

mov fp, r2 // fp = coef_block

add ip, sp, #off_WORKSPACE

VLoopTail:

ldrsh r0, [fp, #VY(0)]

ldrsh r1, [fp, #VY(1)]

ldrsh r2, [fp, #VY(2)]

ldrsh r3, [fp, #VY(3)]

ldrsh r4, [fp, #VY(4)]

ldrsh r5, [fp, #VY(5)]

ldrsh r6, [fp, #VY(6)]

ldrsh r7, [fp, #VY(7)]

cmp r1, #0

orreqs r8, r2, r3

orreqs r8, r4, r5

orreqs r8, r6, r7

beq VLoopHeadZero

VLoopHead:

// tmp0 = DEQUANTIZE(in[DCTSIZE*0], quant[DCTSIZE*0] (r0)

// tmp2 = DEQUANTIZE(in[DCTSIZE*4], quant[DCTSIZE*4] (r4)

// tmp1 = DEQUANTIZE(in[DCTSIZE*2], quant[DCTSIZE*2] (r2)

// tmp3 = DEQUANTIZE(in[DCTSIZE*6], quant[DCTSIZE*6] (r6)

// tmp10 = tmp0 + tmp2 (r0)

// tmp11 = tmp0 - tmp2 (r4)

ldr r9, [r10, #QY(4)]

ldr r8, [r10, #QY(0)]

#if __ARM_HAVE_HALFWORD_MULTIPLY

smulbb r4, r9, r4

smlabb r0, r8, r0, r4

#else

mul r4, r9, r4

mul r0, r8, r0

add r0, r4

#endif

ldr r9, [r10, #QY(6)]

ldr r8, [r10, #QY(2)]

sub r4, r0, r4, lsl #1

#if __ARM_HAVE_HALFWORD_MULTIPLY

smulbb r6, r9, r6

smlabb r2, r8, r2, r6

#else

mul r6, r9, r6

mul r2, r8, r2

add r2, r6

#endif

// tmp13 = tmp1 + tmp3 (r2)

// tmp12 = MULTIPLY(tmp1 - tmp3, FIX_1_414213562) - tmp13 (r6)

// FIX_1_4142... = 362 = 45*8 + 2

sub r6, r2, r6, lsl #1

mov r8, #360

add r8, r8, #2

mul r9, r6, r8

// tmp0 = tmp10 + tmp13; (r0)

// tmp3 = tmp10 - tmp13; (r8)

// tmp1 = tmp11 + tmp12; (r4)

// tmp2 = tmp11 - tmp12; (r6)

add r0, r0, r2

rsb r6, r2, r9, asr #8

sub r8, r0, r2, lsl #1

add r4, r4, r6

sub r6, r4, r6, lsl #1

stmia local_TMP0123, {r0, r4, r6, r8}

// NOTE: be sure to not user r0,r4,r6,r8 soon after stm above

// odd part

// tmp4 = DEQUANTIZE( in[DCTSIZE*1], quant[DCTSIZE*1] ) (r1)

// tmp6 = DEQUANTIZE( in[DCTSIZE*5], quant[DCTSIZE*5] ) (r5)

// tmp5 = DEQUANTIZE( in[DCTSIZE*3], quant[DCTSIZE*3] ) (r3)

// tmp7 = DEQUANTIZE( in[DCTSIZE*7], quant[DCTSIZE*7] ) (r7)

// z13 = tmp6 + tmp5; (r0)

// z10 = tmp6 - tmp5; (r2)

// z11 = tmp4 + tmp7; (r4)

// z12 = tmp4 - tmp7; (r6)

ldr r2, [r10, #QY(1)]

ldr r9, [r10, #QY(5)]

#if __ARM_HAVE_HALFWORD_MULTIPLY

smulbb r1, r2, r1

#else

mul r1, r2, r1

#endif

ldr r2, [r10, #QY(3)]

#if __ARM_HAVE_HALFWORD_MULTIPLY

smulbb r5, r9, r5

#else

mul r5, r9, r5

#endif

ldr r9, [r10, #QY(7)]

#if __ARM_HAVE_HALFWORD_MULTIPLY

smlabb r0, r2, r3, r5

smlabb r4, r9, r7, r1

#else

mul r0, r2, r3

add r0, r5

mul r4, r9, r7

add r4, r1

#endif

rsb r2, r0, r5, lsl #1

rsb r6, r4, r1, lsl #1

// tmp7 = z11 + z13; (r7)

// tmp11 = MULTIPLY(z11 - z13, FIX_1_414213562); (r1)

// FIX_... = 360 + 2

add r7, r4, r0

sub r1, r4, r0

mov r8, #360

add r8, r8, #2

mul r1, r8, r1

// z5 = MULTIPLY(z10 + z12, FIX_1_847759065); (r8)

// tmp10 = MULTIPLY(z12, FIX_1_082392200) - z5; (r0)

// tmp12 = MULTIPLY(z10, - FIX_2_613125930) + z5; (r2)

// FIX_1_8477... = 473 = 472 + 1

// FIX_1_082... = 277 = 276 + 1

// FIX_2_... = 669 = 668 + 1

add r8, r2, r6

mov r9, #472

mla r8, r9, r8, r8

mov r9, #276

mla r0, r6, r9, r6

mov r9, #668

mla r2, r9, r2, r2

sub r0, r0, r8

rsb r2, r2, r8

// tmp6 = tmp12 - tmp7; (r6)

// tmp5 = tmp11 - tmp6; (r5)

// tmp4 = tmp10 + tmp5; (r4)

rsb r6, r7, r2, asr #8

rsb r5, r6, r1, asr #8

add r4, r5, r0, asr #8

ldmia local_TMP0123, {r0, r1, r2, r3}

// wsptr[DCTSIZE*0] = (int) (tmp0 + tmp7);

// wsptr[DCTSIZE*7] = (int) (tmp0 - tmp7);

// wsptr[DCTSIZE*1] = (int) (tmp1 + tmp6);

// wsptr[DCTSIZE*6] = (int) (tmp1 - tmp6);

// wsptr[DCTSIZE*2] = (int) (tmp2 + tmp5);

// wsptr[DCTSIZE*5] = (int) (tmp2 - tmp5);

// wsptr[DCTSIZE*4] = (int) (tmp3 + tmp4);

// wsptr[DCTSIZE*3] = (int) (tmp3 - tmp4);

add r0, r0, r7

sub r7, r0, r7, lsl #1

add r1, r1, r6

sub r6, r1, r6, lsl #1

add r2, r2, r5

sub r5, r2, r5, lsl #1

sub r3, r3, r4

add r4, r3, r4, lsl #1

str r0, [ip, #QY(0)]

str r1, [ip, #QY(1)]

str r2, [ip, #QY(2)]

str r3, [ip, #QY(3)]

str r4, [ip, #QY(4)]

str r5, [ip, #QY(5)]

str r6, [ip, #QY(6)]

str r7, [ip, #QY(7)]

// inptr++; /* advance pointers to next column */

// quantptr++;

// wsptr++;

add fp, fp, #2

add r10, r10, #4

add ip, ip, #4

add r0, sp, #(off_WORKSPACE + 4*8)

cmp ip, r0

bne VLoopTail

HLoopStart:

// reset pointers

PLD [sp, #off_WORKSPACE]

add ip, sp, #off_WORKSPACE

ldr r10, local_RANGE_TABLE

HLoopTail:

// output = *output_buf++ + output_col

ldr r0, local_OUTPUT_BUF

ldr r1, local_OUTPUT_COL

ldr r2, [r0], #4

str r0, local_OUTPUT_BUF

add fp, r2, r1

PLD [ip, #32]

ldmia ip!, {r0-r7}

cmp r1, #0

orreqs r8, r2, r3

orreqs r8, r4, r5

orreqs r8, r6, r7

beq HLoopTailZero

HLoopHead:

// tmp10 = ((DCTELEM) wsptr[0] + (DCTELEM) wsptr[4]); (r0)

// tmp11 = ((DCTELEM) wsptr[0] - (DCTELEM) wsptr[4]); (r4)

add r0, r0, r4

sub r4, r0, r4, lsl #1

// tmp13 = ((DCTELEM) wsptr[2] + (DCTELEM) wsptr[6]); (r2)

// tmp12 = MULTIPLY((DCTELEM) wsptr[2] - (DCTELEM) wsptr[6], FIX_1_414213562) - tmp13; (r6)

// FIX_... = 360 + 2

add r2, r2, r6

sub r6, r2, r6, lsl #1

mov r8, #360

add r8, r8, #2

mul r6, r8, r6

// tmp0 = tmp10 + tmp13; (r0)

// tmp3 = tmp10 - tmp13; (r8)

// tmp1 = tmp11 + tmp12; (r4)

// tmp2 = tmp11 - tmp12; (r6)

add r0, r0, r2

rsb r6, r2, r6, asr #8

sub r8, r0, r2, lsl #1

add r4, r4, r6

sub r6, r4, r6, lsl #1

stmia local_TMP0123, {r0, r4, r6, r8}

// Odd part

// z13 = (DCTELEM) wsptr[5] + (DCTELEM) wsptr[3]; (r0)

// z10 = (DCTELEM) wsptr[5] - (DCTELEM) wsptr[3]; (r2)

// z11 = (DCTELEM) wsptr[1] + (DCTELEM) wsptr[7]; (r4)

// z12 = (DCTELEM) wsptr[1] - (DCTELEM) wsptr[7]; (r6)

add r0, r5, r3

sub r2, r5, r3

add r4, r1, r7

sub r6, r1, r7

// tmp7 = z11 + z13; (r7)

// tmp11 = MULTIPLY(z11 - z13, FIX_1_414213562); (r1)

// FIX_... = 360 + 2

add r7, r4, r0

sub r1, r4, r0

mov r8, #360

add r8, r8, #2

mul r1, r8, r1

// z5 = MULTIPLY(z10 + z12, FIX_1_847759065); (r8)

// tmp10 = MULTIPLY(z12, FIX_1_082392200) - z5; (r0)

// tmp12 = MULTIPLY(z10, - FIX_2_613125930) + z5; (r2)

// FIX_1_8477... = 473 = 472 + 1

// FIX_1_082... = 277 = 276 + 1

// FIX_2_... = 669 = 668 + 1

add r8, r2, r6

mov r9, #472

mla r8, r9, r8, r8

mov r9, #276

mla r0, r6, r9, r6

mov r9, #668

mla r2, r9, r2, r2

sub r0, r0, r8

sub r2, r8, r2

// tmp6 = tmp12 - tmp7; (r6)

// tmp5 = tmp11 - tmp6; (r5)

// tmp4 = tmp10 + tmp5; (r4)

rsb r6, r7, r2, asr #8

rsb r5, r6, r1, asr #8

add r4, r5, r0, asr #8

ldmia local_TMP0123, {r0, r1, r2, r3}

// outptr[0] = range_limit[IDESCALE(tmp0 + tmp7, PASS1_BITS+3) & RANGE_MASK];

// outptr[7] = range_limit[IDESCALE(tmp0 - tmp7, PASS1_BITS+3) & RANGE_MASK];

// outptr[1] = range_limit[IDESCALE(tmp1 + tmp6, PASS1_BITS+3) & RANGE_MASK];

// outptr[6] = range_limit[IDESCALE(tmp1 - tmp6, PASS1_BITS+3) & RANGE_MASK];

// outptr[2] = range_limit[IDESCALE(tmp2 + tmp5, PASS1_BITS+3) & RANGE_MASK];

// outptr[5] = range_limit[IDESCALE(tmp2 - tmp5, PASS1_BITS+3) & RANGE_MASK];

// outptr[4] = range_limit[IDESCALE(tmp3 + tmp4, PASS1_BITS+3) & RANGE_MASK];

// outptr[3] = range_limit[IDESCALE(tmp3 - tmp4, PASS1_BITS+3) & RANGE_MASK];

mov r8, #128

add r0, r0, r7

sub r7, r0, r7, lsl #1

add r0, r8, r0, asr #5

add r7, r8, r7, asr #5

add r1, r1, r6

sub r6, r1, r6, lsl #1

add r1, r8, r1, asr #5

add r6, r8, r6, asr #5

add r2, r2, r5

sub r5, r2, r5, lsl #1

add r2, r8, r2, asr #5

add r5, r8, r5, asr #5

sub r3, r3, r4

add r4, r3, r4, lsl #1

add r3, r8, r3, asr #5

add r4, r8, r4, asr #5

#if __ARM_ARCH__ >= 6

usat r0, #8, r0

usat r1, #8, r1

usat r2, #8, r2

usat r3, #8, r3

usat r4, #8, r4

usat r5, #8, r5

usat r6, #8, r6

usat r7, #8, r7

#else

cmp r0, #255

mvnhi r0, r0, asr #31

andhi r0, #255

cmp r7, #255

mvnhi r7, r7, asr #31

cmp r1, #255

mvnhi r1, r1, asr #31

andhi r1, #255

cmp r6, #255

mvnhi r6, r6, asr #31

andhi r6, #255

cmp r2, #255

mvnhi r2, r2, asr #31

andhi r2, #255

cmp r5, #255

mvnhi r5, r5, asr #31

andhi r5, #255

cmp r3, #255

mvnhi r3, r3, asr #31

cmp r4, #255

mvnhi r4, r4, asr #31

andhi r4, #255

#endif

// r3 r2 r1 r0

orr r0, r0, r1, lsl #8

orr r0, r0, r2, lsl #16

orr r0, r0, r3, lsl #24

// r7 r6 r5 r4

orr r1, r4, r5, lsl #8

orr r1, r1, r6, lsl #16

orr r1, r1, r7, lsl #24

stmia fp, {r0, r1}

add r0, sp, #(off_WORKSPACE + 8*8*4)

cmp ip, r0

bne HLoopTail

Exit:

add sp, sp, #local_SIZE

ldmia sp!, {r4,r5, r6,r7, r8,r9, r10,r11, r12,lr}

bx lr

VLoopHeadZero:

// ok, all AC coefficients are 0

ldr r1, [r10, #QY(0)]

add fp, fp, #2

add r10, r10, #4

mul r0, r1, r0

str r0, [ip, #QY(0)]

str r0, [ip, #QY(1)]

str r0, [ip, #QY(2)]

str r0, [ip, #QY(3)]

str r0, [ip, #QY(4)]

str r0, [ip, #QY(5)]

str r0, [ip, #QY(6)]

str r0, [ip, #QY(7)]

add ip, ip, #4

add r0, sp, #(off_WORKSPACE + 4*8)

cmp ip, r0

beq HLoopStart

b VLoopTail

HLoopTailZero:

mov r0, r0, asr #5

add r0, #128

#if __ARM_ARCH__ >= 6

usat r0, #8, r0

#else

cmp r0, #255

mvnhi r0, r0, asr #31

andhi r0, r0, #255

#endif

orr r0, r0, lsl #8

orr r0, r0, lsl #16

mov r1, r0

stmia fp, {r0, r1}

add r0, sp, #(off_WORKSPACE + 64*4)

cmp ip, r0

beq Exit

b HLoopTail

.endfunc