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Diffstat (limited to 'src/libffmpeg/libavcodec/armv4l/simple_idct_arm.S')
-rw-r--r--src/libffmpeg/libavcodec/armv4l/simple_idct_arm.S487
1 files changed, 0 insertions, 487 deletions
diff --git a/src/libffmpeg/libavcodec/armv4l/simple_idct_arm.S b/src/libffmpeg/libavcodec/armv4l/simple_idct_arm.S
deleted file mode 100644
index b5a20f6da..000000000
--- a/src/libffmpeg/libavcodec/armv4l/simple_idct_arm.S
+++ /dev/null
@@ -1,487 +0,0 @@
-/*
- * simple_idct_arm.S
- * Copyright (C) 2002 Frederic 'dilb' Boulay.
- * All Rights Reserved.
- *
- * Author: Frederic Boulay <dilb@handhelds.org>
- *
- * This file is part of FFmpeg.
- *
- * FFmpeg is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * FFmpeg is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- *
- * The function defined in this file, is derived from the simple_idct function
- * from the libavcodec library part of the ffmpeg project.
- */
-
-/* useful constants for the algorithm, they are save in __constant_ptr__ at */
-/* the end of the source code.*/
-#define W1 22725
-#define W2 21407
-#define W3 19266
-#define W4 16383
-#define W5 12873
-#define W6 8867
-#define W7 4520
-#define MASK_MSHW 0xFFFF0000
-
-/* offsets of the constants in the vector */
-#define offW1 0
-#define offW2 4
-#define offW3 8
-#define offW4 12
-#define offW5 16
-#define offW6 20
-#define offW7 24
-#define offMASK_MSHW 28
-
-#define ROW_SHIFT 11
-#define ROW_SHIFT2MSHW (16-11)
-#define COL_SHIFT 20
-#define ROW_SHIFTED_1 1024 /* 1<< (ROW_SHIFT-1) */
-#define COL_SHIFTED_1 524288 /* 1<< (COL_SHIFT-1) */
-
-
- .text
- .align
- .global simple_idct_ARM
-
-simple_idct_ARM:
- @@ void simple_idct_ARM(int16_t *block)
- @@ save stack for reg needed (take all of them),
- @@ R0-R3 are scratch regs, so no need to save them, but R0 contains the pointer to block
- @@ so it must not be overwritten, if it is not saved!!
- @@ R12 is another scratch register, so it should not be saved too
- @@ save all registers
- stmfd sp!, {r4-r11, r14} @ R14 is also called LR
- @@ at this point, R0=block, other registers are free.
- add r14, r0, #112 @ R14=&block[8*7], better start from the last row, and decrease the value until row=0, i.e. R12=block.
- add r12, pc, #(__constant_ptr__-.-8) @ R12=__constant_ptr__, the vector containing the constants, probably not necessary to reserve a register for it
- @@ add 2 temporary variables in the stack: R0 and R14
- sub sp, sp, #8 @ allow 2 local variables
- str r0, [sp, #0] @ save block in sp[0]
- @@ stack status
- @@ sp+4 free
- @@ sp+0 R0 (block)
-
-
- @@ at this point, R0=block, R14=&block[56], R12=__const_ptr_, R1-R11 free
-
-
-__row_loop:
- @@ read the row and check if it is null, almost null, or not, according to strongarm specs, it is not necessary to optimise ldr accesses (i.e. split 32bits in 2 16bits words), at least it gives more usable registers :)
- ldr r1, [r14, #0] @ R1=(int32)(R12)[0]=ROWr32[0] (relative row cast to a 32b pointer)
- ldr r2, [r14, #4] @ R2=(int32)(R12)[1]=ROWr32[1]
- ldr r3, [r14, #8] @ R3=ROWr32[2]
- ldr r4, [r14, #12] @ R4=ROWr32[3]
- @@ check if the words are null, if all of them are null, then proceed with next row (branch __end_row_loop),
- @@ if ROWr16[0] is the only one not null, then proceed with this special case (branch __almost_empty_row)
- @@ else follow the complete algorithm.
- @@ at this point, R0=block, R14=&block[n], R12=__const_ptr_, R1=ROWr32[0], R2=ROWr32[1],
- @@ R3=ROWr32[2], R4=ROWr32[3], R5-R11 free
- orr r5, r4, r3 @ R5=R4 | R3
- orr r5, r5, r2 @ R5=R4 | R3 | R2
- orrs r6, r5, r1 @ Test R5 | R1 (the aim is to check if everything is null)
- beq __end_row_loop
- mov r7, r1, asr #16 @ R7=R1>>16=ROWr16[1] (evaluate it now, as it could be useful later)
- ldrsh r6, [r14, #0] @ R6=ROWr16[0]
- orrs r5, r5, r7 @ R5=R4 | R3 | R2 | R7
- beq __almost_empty_row
-
-__b_evaluation:
- @@ at this point, R0=block (temp), R1(free), R2=ROWr32[1], R3=ROWr32[2], R4=ROWr32[3],
- @@ R5=(temp), R6=ROWr16[0], R7=ROWr16[1], R8-R11 free,
- @@ R12=__const_ptr_, R14=&block[n]
- @@ to save some registers/calls, proceed with b0-b3 first, followed by a0-a3
-
- @@ MUL16(b0, W1, row[1]);
- @@ MUL16(b1, W3, row[1]);
- @@ MUL16(b2, W5, row[1]);
- @@ MUL16(b3, W7, row[1]);
- @@ MAC16(b0, W3, row[3]);
- @@ MAC16(b1, -W7, row[3]);
- @@ MAC16(b2, -W1, row[3]);
- @@ MAC16(b3, -W5, row[3]);
- ldr r8, [r12, #offW1] @ R8=W1
- mov r2, r2, asr #16 @ R2=ROWr16[3]
- mul r0, r8, r7 @ R0=W1*ROWr16[1]=b0 (ROWr16[1] must be the second arg, to have the possibility to save 1 cycle)
- ldr r9, [r12, #offW3] @ R9=W3
- ldr r10, [r12, #offW5] @ R10=W5
- mul r1, r9, r7 @ R1=W3*ROWr16[1]=b1 (ROWr16[1] must be the second arg, to have the possibility to save 1 cycle)
- ldr r11, [r12, #offW7] @ R11=W7
- mul r5, r10, r7 @ R5=W5*ROWr16[1]=b2 (ROWr16[1] must be the second arg, to have the possibility to save 1 cycle)
- mul r7, r11, r7 @ R7=W7*ROWr16[1]=b3 (ROWr16[1] must be the second arg, to have the possibility to save 1 cycle)
- teq r2, #0 @ if null avoid muls
- mlane r0, r9, r2, r0 @ R0+=W3*ROWr16[3]=b0 (ROWr16[3] must be the second arg, to have the possibility to save 1 cycle)
- rsbne r2, r2, #0 @ R2=-ROWr16[3]
- mlane r1, r11, r2, r1 @ R1-=W7*ROWr16[3]=b1 (ROWr16[3] must be the second arg, to have the possibility to save 1 cycle)
- mlane r5, r8, r2, r5 @ R5-=W1*ROWr16[3]=b2 (ROWr16[3] must be the second arg, to have the possibility to save 1 cycle)
- mlane r7, r10, r2, r7 @ R7-=W5*ROWr16[3]=b3 (ROWr16[3] must be the second arg, to have the possibility to save 1 cycle)
-
- @@ at this point, R0=b0, R1=b1, R2 (free), R3=ROWr32[2], R4=ROWr32[3],
- @@ R5=b2, R6=ROWr16[0], R7=b3, R8=W1, R9=W3, R10=W5, R11=W7,
- @@ R12=__const_ptr_, R14=&block[n]
- @@ temp = ((uint32_t*)row)[2] | ((uint32_t*)row)[3];
- @@ if (temp != 0) {}
- orrs r2, r3, r4 @ R2=ROWr32[2] | ROWr32[3]
- beq __end_b_evaluation
-
- @@ at this point, R0=b0, R1=b1, R2 (free), R3=ROWr32[2], R4=ROWr32[3],
- @@ R5=b2, R6=ROWr16[0], R7=b3, R8=W1, R9=W3, R10=W5, R11=W7,
- @@ R12=__const_ptr_, R14=&block[n]
- @@ MAC16(b0, W5, row[5]);
- @@ MAC16(b2, W7, row[5]);
- @@ MAC16(b3, W3, row[5]);
- @@ MAC16(b1, -W1, row[5]);
- @@ MAC16(b0, W7, row[7]);
- @@ MAC16(b2, W3, row[7]);
- @@ MAC16(b3, -W1, row[7]);
- @@ MAC16(b1, -W5, row[7]);
- mov r3, r3, asr #16 @ R3=ROWr16[5]
- teq r3, #0 @ if null avoid muls
- mlane r0, r10, r3, r0 @ R0+=W5*ROWr16[5]=b0
- mov r4, r4, asr #16 @ R4=ROWr16[7]
- mlane r5, r11, r3, r5 @ R5+=W7*ROWr16[5]=b2
- mlane r7, r9, r3, r7 @ R7+=W3*ROWr16[5]=b3
- rsbne r3, r3, #0 @ R3=-ROWr16[5]
- mlane r1, r8, r3, r1 @ R7-=W1*ROWr16[5]=b1
- @@ R3 is free now
- teq r4, #0 @ if null avoid muls
- mlane r0, r11, r4, r0 @ R0+=W7*ROWr16[7]=b0
- mlane r5, r9, r4, r5 @ R5+=W3*ROWr16[7]=b2
- rsbne r4, r4, #0 @ R4=-ROWr16[7]
- mlane r7, r8, r4, r7 @ R7-=W1*ROWr16[7]=b3
- mlane r1, r10, r4, r1 @ R1-=W5*ROWr16[7]=b1
- @@ R4 is free now
-__end_b_evaluation:
- @@ at this point, R0=b0, R1=b1, R2=ROWr32[2] | ROWr32[3] (tmp), R3 (free), R4 (free),
- @@ R5=b2, R6=ROWr16[0], R7=b3, R8 (free), R9 (free), R10 (free), R11 (free),
- @@ R12=__const_ptr_, R14=&block[n]
-
-__a_evaluation:
- @@ a0 = (W4 * row[0]) + (1 << (ROW_SHIFT - 1));
- @@ a1 = a0 + W6 * row[2];
- @@ a2 = a0 - W6 * row[2];
- @@ a3 = a0 - W2 * row[2];
- @@ a0 = a0 + W2 * row[2];
- ldr r9, [r12, #offW4] @ R9=W4
- mul r6, r9, r6 @ R6=W4*ROWr16[0]
- ldr r10, [r12, #offW6] @ R10=W6
- ldrsh r4, [r14, #4] @ R4=ROWr16[2] (a3 not defined yet)
- add r6, r6, #ROW_SHIFTED_1 @ R6=W4*ROWr16[0] + 1<<(ROW_SHIFT-1) (a0)
-
- mul r11, r10, r4 @ R11=W6*ROWr16[2]
- ldr r8, [r12, #offW2] @ R8=W2
- sub r3, r6, r11 @ R3=a0-W6*ROWr16[2] (a2)
- @@ temp = ((uint32_t*)row)[2] | ((uint32_t*)row)[3];
- @@ if (temp != 0) {}
- teq r2, #0
- beq __end_bef_a_evaluation
-
- add r2, r6, r11 @ R2=a0+W6*ROWr16[2] (a1)
- mul r11, r8, r4 @ R11=W2*ROWr16[2]
- sub r4, r6, r11 @ R4=a0-W2*ROWr16[2] (a3)
- add r6, r6, r11 @ R6=a0+W2*ROWr16[2] (a0)
-
-
- @@ at this point, R0=b0, R1=b1, R2=a1, R3=a2, R4=a3,
- @@ R5=b2, R6=a0, R7=b3, R8=W2, R9=W4, R10=W6, R11 (free),
- @@ R12=__const_ptr_, R14=&block[n]
-
-
- @@ a0 += W4*row[4]
- @@ a1 -= W4*row[4]
- @@ a2 -= W4*row[4]
- @@ a3 += W4*row[4]
- ldrsh r11, [r14, #8] @ R11=ROWr16[4]
- teq r11, #0 @ if null avoid muls
- mulne r11, r9, r11 @ R11=W4*ROWr16[4]
- @@ R9 is free now
- ldrsh r9, [r14, #12] @ R9=ROWr16[6]
- addne r6, r6, r11 @ R6+=W4*ROWr16[4] (a0)
- subne r2, r2, r11 @ R2-=W4*ROWr16[4] (a1)
- subne r3, r3, r11 @ R3-=W4*ROWr16[4] (a2)
- addne r4, r4, r11 @ R4+=W4*ROWr16[4] (a3)
- @@ W6 alone is no more useful, save W2*ROWr16[6] in it instead
- teq r9, #0 @ if null avoid muls
- mulne r11, r10, r9 @ R11=W6*ROWr16[6]
- addne r6, r6, r11 @ R6+=W6*ROWr16[6] (a0)
- mulne r10, r8, r9 @ R10=W2*ROWr16[6]
- @@ a0 += W6*row[6];
- @@ a3 -= W6*row[6];
- @@ a1 -= W2*row[6];
- @@ a2 += W2*row[6];
- subne r4, r4, r11 @ R4-=W6*ROWr16[6] (a3)
- subne r2, r2, r10 @ R2-=W2*ROWr16[6] (a1)
- addne r3, r3, r10 @ R3+=W2*ROWr16[6] (a2)
-
-__end_a_evaluation:
- @@ at this point, R0=b0, R1=b1, R2=a1, R3=a2, R4=a3,
- @@ R5=b2, R6=a0, R7=b3, R8 (free), R9 (free), R10 (free), R11 (free),
- @@ R12=__const_ptr_, R14=&block[n]
- @@ row[0] = (a0 + b0) >> ROW_SHIFT;
- @@ row[1] = (a1 + b1) >> ROW_SHIFT;
- @@ row[2] = (a2 + b2) >> ROW_SHIFT;
- @@ row[3] = (a3 + b3) >> ROW_SHIFT;
- @@ row[4] = (a3 - b3) >> ROW_SHIFT;
- @@ row[5] = (a2 - b2) >> ROW_SHIFT;
- @@ row[6] = (a1 - b1) >> ROW_SHIFT;
- @@ row[7] = (a0 - b0) >> ROW_SHIFT;
- add r8, r6, r0 @ R8=a0+b0
- add r9, r2, r1 @ R9=a1+b1
- @@ put 2 16 bits half-words in a 32bits word
- @@ ROWr32[0]=ROWr16[0] | (ROWr16[1]<<16) (only Little Endian compliant then!!!)
- ldr r10, [r12, #offMASK_MSHW] @ R10=0xFFFF0000
- and r9, r10, r9, lsl #ROW_SHIFT2MSHW @ R9=0xFFFF0000 & ((a1+b1)<<5)
- mvn r11, r10 @ R11= NOT R10= 0x0000FFFF
- and r8, r11, r8, asr #ROW_SHIFT @ R8=0x0000FFFF & ((a0+b0)>>11)
- orr r8, r8, r9
- str r8, [r14, #0]
-
- add r8, r3, r5 @ R8=a2+b2
- add r9, r4, r7 @ R9=a3+b3
- and r9, r10, r9, lsl #ROW_SHIFT2MSHW @ R9=0xFFFF0000 & ((a3+b3)<<5)
- and r8, r11, r8, asr #ROW_SHIFT @ R8=0x0000FFFF & ((a2+b2)>>11)
- orr r8, r8, r9
- str r8, [r14, #4]
-
- sub r8, r4, r7 @ R8=a3-b3
- sub r9, r3, r5 @ R9=a2-b2
- and r9, r10, r9, lsl #ROW_SHIFT2MSHW @ R9=0xFFFF0000 & ((a2-b2)<<5)
- and r8, r11, r8, asr #ROW_SHIFT @ R8=0x0000FFFF & ((a3-b3)>>11)
- orr r8, r8, r9
- str r8, [r14, #8]
-
- sub r8, r2, r1 @ R8=a1-b1
- sub r9, r6, r0 @ R9=a0-b0
- and r9, r10, r9, lsl #ROW_SHIFT2MSHW @ R9=0xFFFF0000 & ((a0-b0)<<5)
- and r8, r11, r8, asr #ROW_SHIFT @ R8=0x0000FFFF & ((a1-b1)>>11)
- orr r8, r8, r9
- str r8, [r14, #12]
-
- bal __end_row_loop
-
-__almost_empty_row:
- @@ the row was empty, except ROWr16[0], now, management of this special case
- @@ at this point, R0=block, R14=&block[n], R12=__const_ptr_, R1=ROWr32[0], R2=ROWr32[1],
- @@ R3=ROWr32[2], R4=ROWr32[3], R5=(temp), R6=ROWr16[0], R7=ROWr16[1],
- @@ R8=0xFFFF (temp), R9-R11 free
- mov r8, #0x10000 @ R8=0xFFFF (2 steps needed!) it saves a ldr call (because of delay run).
- sub r8, r8, #1 @ R8 is now ready.
- and r5, r8, r6, lsl #3 @ R5=R8 & (R6<<3)= (ROWr16[0]<<3) & 0xFFFF
- orr r5, r5, r5, lsl #16 @ R5=R5 | (R5<<16)
- str r5, [r14, #0] @ R14[0]=ROWr32[0]=R5
- str r5, [r14, #4] @ R14[4]=ROWr32[1]=R5
- str r5, [r14, #8] @ R14[8]=ROWr32[2]=R5
- str r5, [r14, #12] @ R14[12]=ROWr32[3]=R5
-
-__end_row_loop:
- @@ at this point, R0-R11 (free)
- @@ R12=__const_ptr_, R14=&block[n]
- ldr r0, [sp, #0] @ R0=block
- teq r0, r14 @ compare current &block[8*n] to block, when block is reached, the loop is finished.
- sub r14, r14, #16
- bne __row_loop
-
-
-
- @@ at this point, R0=block, R1-R11 (free)
- @@ R12=__const_ptr_, R14=&block[n]
- add r14, r0, #14 @ R14=&block[7], better start from the last col, and decrease the value until col=0, i.e. R14=block.
-__col_loop:
-
-__b_evaluation2:
- @@ at this point, R0=block (temp), R1-R11 (free)
- @@ R12=__const_ptr_, R14=&block[n]
- @@ proceed with b0-b3 first, followed by a0-a3
- @@ MUL16(b0, W1, col[8x1]);
- @@ MUL16(b1, W3, col[8x1]);
- @@ MUL16(b2, W5, col[8x1]);
- @@ MUL16(b3, W7, col[8x1]);
- @@ MAC16(b0, W3, col[8x3]);
- @@ MAC16(b1, -W7, col[8x3]);
- @@ MAC16(b2, -W1, col[8x3]);
- @@ MAC16(b3, -W5, col[8x3]);
- ldr r8, [r12, #offW1] @ R8=W1
- ldrsh r7, [r14, #16]
- mul r0, r8, r7 @ R0=W1*ROWr16[1]=b0 (ROWr16[1] must be the second arg, to have the possibility to save 1 cycle)
- ldr r9, [r12, #offW3] @ R9=W3
- ldr r10, [r12, #offW5] @ R10=W5
- mul r1, r9, r7 @ R1=W3*ROWr16[1]=b1 (ROWr16[1] must be the second arg, to have the possibility to save 1 cycle)
- ldr r11, [r12, #offW7] @ R11=W7
- mul r5, r10, r7 @ R5=W5*ROWr16[1]=b2 (ROWr16[1] must be the second arg, to have the possibility to save 1 cycle)
- ldrsh r2, [r14, #48]
- mul r7, r11, r7 @ R7=W7*ROWr16[1]=b3 (ROWr16[1] must be the second arg, to have the possibility to save 1 cycle)
- teq r2, #0 @ if 0, then avoid muls
- mlane r0, r9, r2, r0 @ R0+=W3*ROWr16[3]=b0 (ROWr16[3] must be the second arg, to have the possibility to save 1 cycle)
- rsbne r2, r2, #0 @ R2=-ROWr16[3]
- mlane r1, r11, r2, r1 @ R1-=W7*ROWr16[3]=b1 (ROWr16[3] must be the second arg, to have the possibility to save 1 cycle)
- mlane r5, r8, r2, r5 @ R5-=W1*ROWr16[3]=b2 (ROWr16[3] must be the second arg, to have the possibility to save 1 cycle)
- mlane r7, r10, r2, r7 @ R7-=W5*ROWr16[3]=b3 (ROWr16[3] must be the second arg, to have the possibility to save 1 cycle)
-
- @@ at this point, R0=b0, R1=b1, R2 (free), R3 (free), R4 (free),
- @@ R5=b2, R6 (free), R7=b3, R8=W1, R9=W3, R10=W5, R11=W7,
- @@ R12=__const_ptr_, R14=&block[n]
- @@ MAC16(b0, W5, col[5x8]);
- @@ MAC16(b2, W7, col[5x8]);
- @@ MAC16(b3, W3, col[5x8]);
- @@ MAC16(b1, -W1, col[5x8]);
- @@ MAC16(b0, W7, col[7x8]);
- @@ MAC16(b2, W3, col[7x8]);
- @@ MAC16(b3, -W1, col[7x8]);
- @@ MAC16(b1, -W5, col[7x8]);
- ldrsh r3, [r14, #80] @ R3=COLr16[5x8]
- teq r3, #0 @ if 0 then avoid muls
- mlane r0, r10, r3, r0 @ R0+=W5*ROWr16[5x8]=b0
- mlane r5, r11, r3, r5 @ R5+=W7*ROWr16[5x8]=b2
- mlane r7, r9, r3, r7 @ R7+=W3*ROWr16[5x8]=b3
- rsbne r3, r3, #0 @ R3=-ROWr16[5x8]
- ldrsh r4, [r14, #112] @ R4=COLr16[7x8]
- mlane r1, r8, r3, r1 @ R7-=W1*ROWr16[5x8]=b1
- @@ R3 is free now
- teq r4, #0 @ if 0 then avoid muls
- mlane r0, r11, r4, r0 @ R0+=W7*ROWr16[7x8]=b0
- mlane r5, r9, r4, r5 @ R5+=W3*ROWr16[7x8]=b2
- rsbne r4, r4, #0 @ R4=-ROWr16[7x8]
- mlane r7, r8, r4, r7 @ R7-=W1*ROWr16[7x8]=b3
- mlane r1, r10, r4, r1 @ R1-=W5*ROWr16[7x8]=b1
- @@ R4 is free now
-__end_b_evaluation2:
- @@ at this point, R0=b0, R1=b1, R2 (free), R3 (free), R4 (free),
- @@ R5=b2, R6 (free), R7=b3, R8 (free), R9 (free), R10 (free), R11 (free),
- @@ R12=__const_ptr_, R14=&block[n]
-
-__a_evaluation2:
- @@ a0 = (W4 * col[8x0]) + (1 << (COL_SHIFT - 1));
- @@ a1 = a0 + W6 * row[2];
- @@ a2 = a0 - W6 * row[2];
- @@ a3 = a0 - W2 * row[2];
- @@ a0 = a0 + W2 * row[2];
- ldrsh r6, [r14, #0]
- ldr r9, [r12, #offW4] @ R9=W4
- mul r6, r9, r6 @ R6=W4*ROWr16[0]
- ldr r10, [r12, #offW6] @ R10=W6
- ldrsh r4, [r14, #32] @ R4=ROWr16[2] (a3 not defined yet)
- add r6, r6, #COL_SHIFTED_1 @ R6=W4*ROWr16[0] + 1<<(COL_SHIFT-1) (a0)
- mul r11, r10, r4 @ R11=W6*ROWr16[2]
- ldr r8, [r12, #offW2] @ R8=W2
- add r2, r6, r11 @ R2=a0+W6*ROWr16[2] (a1)
- sub r3, r6, r11 @ R3=a0-W6*ROWr16[2] (a2)
- mul r11, r8, r4 @ R11=W2*ROWr16[2]
- sub r4, r6, r11 @ R4=a0-W2*ROWr16[2] (a3)
- add r6, r6, r11 @ R6=a0+W2*ROWr16[2] (a0)
-
- @@ at this point, R0=b0, R1=b1, R2=a1, R3=a2, R4=a3,
- @@ R5=b2, R6=a0, R7=b3, R8=W2, R9=W4, R10=W6, R11 (free),
- @@ R12=__const_ptr_, R14=&block[n]
- @@ a0 += W4*row[4]
- @@ a1 -= W4*row[4]
- @@ a2 -= W4*row[4]
- @@ a3 += W4*row[4]
- ldrsh r11, [r14, #64] @ R11=ROWr16[4]
- teq r11, #0 @ if null avoid muls
- mulne r11, r9, r11 @ R11=W4*ROWr16[4]
- @@ R9 is free now
- addne r6, r6, r11 @ R6+=W4*ROWr16[4] (a0)
- subne r2, r2, r11 @ R2-=W4*ROWr16[4] (a1)
- subne r3, r3, r11 @ R3-=W4*ROWr16[4] (a2)
- ldrsh r9, [r14, #96] @ R9=ROWr16[6]
- addne r4, r4, r11 @ R4+=W4*ROWr16[4] (a3)
- @@ W6 alone is no more useful, save W2*ROWr16[6] in it instead
- teq r9, #0 @ if null avoid muls
- mulne r11, r10, r9 @ R11=W6*ROWr16[6]
- addne r6, r6, r11 @ R6+=W6*ROWr16[6] (a0)
- mulne r10, r8, r9 @ R10=W2*ROWr16[6]
- @@ a0 += W6*row[6];
- @@ a3 -= W6*row[6];
- @@ a1 -= W2*row[6];
- @@ a2 += W2*row[6];
- subne r4, r4, r11 @ R4-=W6*ROWr16[6] (a3)
- subne r2, r2, r10 @ R2-=W2*ROWr16[6] (a1)
- addne r3, r3, r10 @ R3+=W2*ROWr16[6] (a2)
-__end_a_evaluation2:
- @@ at this point, R0=b0, R1=b1, R2=a1, R3=a2, R4=a3,
- @@ R5=b2, R6=a0, R7=b3, R8 (free), R9 (free), R10 (free), R11 (free),
- @@ R12=__const_ptr_, R14=&block[n]
- @@ col[0 ] = ((a0 + b0) >> COL_SHIFT);
- @@ col[8 ] = ((a1 + b1) >> COL_SHIFT);
- @@ col[16] = ((a2 + b2) >> COL_SHIFT);
- @@ col[24] = ((a3 + b3) >> COL_SHIFT);
- @@ col[32] = ((a3 - b3) >> COL_SHIFT);
- @@ col[40] = ((a2 - b2) >> COL_SHIFT);
- @@ col[48] = ((a1 - b1) >> COL_SHIFT);
- @@ col[56] = ((a0 - b0) >> COL_SHIFT);
- @@@@@ no optimisation here @@@@@
- add r8, r6, r0 @ R8=a0+b0
- add r9, r2, r1 @ R9=a1+b1
- mov r8, r8, asr #COL_SHIFT
- mov r9, r9, asr #COL_SHIFT
- strh r8, [r14, #0]
- strh r9, [r14, #16]
- add r8, r3, r5 @ R8=a2+b2
- add r9, r4, r7 @ R9=a3+b3
- mov r8, r8, asr #COL_SHIFT
- mov r9, r9, asr #COL_SHIFT
- strh r8, [r14, #32]
- strh r9, [r14, #48]
- sub r8, r4, r7 @ R8=a3-b3
- sub r9, r3, r5 @ R9=a2-b2
- mov r8, r8, asr #COL_SHIFT
- mov r9, r9, asr #COL_SHIFT
- strh r8, [r14, #64]
- strh r9, [r14, #80]
- sub r8, r2, r1 @ R8=a1-b1
- sub r9, r6, r0 @ R9=a0-b0
- mov r8, r8, asr #COL_SHIFT
- mov r9, r9, asr #COL_SHIFT
- strh r8, [r14, #96]
- strh r9, [r14, #112]
-
-__end_col_loop:
- @@ at this point, R0-R11 (free)
- @@ R12=__const_ptr_, R14=&block[n]
- ldr r0, [sp, #0] @ R0=block
- teq r0, r14 @ compare current &block[n] to block, when block is reached, the loop is finished.
- sub r14, r14, #2
- bne __col_loop
-
-
-
-
-__end_simple_idct_ARM:
- @@ restore registers to previous status!
- add sp, sp, #8 @@ the local variables!
- ldmfd sp!, {r4-r11, r15} @@ update PC with LR content.
-
-
-
-@@ kind of sub-function, here not to overload the common case.
-__end_bef_a_evaluation:
- add r2, r6, r11 @ R2=a0+W6*ROWr16[2] (a1)
- mul r11, r8, r4 @ R11=W2*ROWr16[2]
- sub r4, r6, r11 @ R4=a0-W2*ROWr16[2] (a3)
- add r6, r6, r11 @ R6=a0+W2*ROWr16[2] (a0)
- bal __end_a_evaluation
-
-
-__constant_ptr__: @@ see #defines at the beginning of the source code for values.
- .align
- .word W1
- .word W2
- .word W3
- .word W4
- .word W5
- .word W6
- .word W7
- .word MASK_MSHW
generated by cgit v1.2.3 (git 2.25.1) at 2025-04-25 18:18:31 +0000