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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
.arch armv7-a
.fpu neon
/* Allow to build on targets not supporting neon, and force the object file
* target to avoid bumping the final binary target */
.object_arch armv4t
.text
.align
.balign 64
YCbCr42xToRGB565_DITHER03_CONSTS_NEON:
.short -14240
.short -14240+384
.short 8672
.short 8672+192
.short -17696
.short -17696+384
.byte 102
.byte 25
.byte 52
.byte 129
YCbCr42xToRGB565_DITHER12_CONSTS_NEON:
.short -14240+128
.short -14240+256
.short 8672+64
.short 8672+128
.short -17696+128
.short -17696+256
.byte 102
.byte 25
.byte 52
.byte 129
YCbCr42xToRGB565_DITHER21_CONSTS_NEON:
.short -14240+256
.short -14240+128
.short 8672+128
.short 8672+64
.short -17696+256
.short -17696+128
.byte 102
.byte 25
.byte 52
.byte 129
YCbCr42xToRGB565_DITHER30_CONSTS_NEON:
.short -14240+384
.short -14240
.short 8672+192
.short 8672
.short -17696+384
.short -17696
.byte 102
.byte 25
.byte 52
.byte 129
@ void ScaleYCbCr42xToRGB565_BilinearY_Row_NEON(
@ yuv2rgb565_row_scale_bilinear_ctx *ctx, int dither);
@
@ ctx = {
@ uint16_t *rgb_row; /*r0*/
@ const uint8_t *y_row; /*r1*/
@ const uint8_t *u_row; /*r2*/
@ const uint8_t *v_row; /*r3*/
@ int y_yweight; /*r4*/
@ int y_pitch; /*r5*/
@ int width; /*r6*/
@ int source_x0_q16; /*r7*/
@ int source_dx_q16; /*r8*/
@ int source_uv_xoffs_q16; /*r9*/
@ };
.global ScaleYCbCr42xToRGB565_BilinearY_Row_NEON
.type ScaleYCbCr42xToRGB565_BilinearY_Row_NEON, %function
.balign 64
.fnstart
ScaleYCbCr42xToRGB565_BilinearY_Row_NEON:
STMFD r13!,{r4-r9,r14} @ 8 words.
ADR r14,YCbCr42xToRGB565_DITHER03_CONSTS_NEON
VPUSH {Q4-Q7} @ 16 words.
ADD r14,r14,r1, LSL #4 @ Select the dither table to use
LDMIA r0, {r0-r9}
@ Set up image index registers.
ADD r12,r8, r8
VMOV.I32 D16,#0 @ Q8 = < 2| 2| 0| 0>*source_dx_q16
VDUP.32 D17,r12
ADD r12,r12,r12
VTRN.32 D16,D17 @ Q2 = < 2| 0| 2| 0>*source_dx_q16
VDUP.32 D19,r12 @ Q9 = < 4| 4| ?| ?>*source_dx_q16
ADD r12,r12,r12
VDUP.32 Q0, r7 @ Q0 = < 1| 1| 1| 1>*source_x0_q16
VADD.I32 D17,D17,D19 @ Q8 = < 6| 4| 2| 0>*source_dx_q16
CMP r8, #0 @ If source_dx_q16 is negative...
VDUP.32 Q9, r12 @ Q9 = < 8| 8| 8| 8>*source_dx_q16
ADDLT r7, r7, r8, LSL #4 @ Make r7 point to the end of the block
VADD.I32 Q0, Q0, Q8 @ Q0 = < 6| 4| 2| 0>*source_dx_q16+source_x0_q16
SUBLT r7, r7, r8 @ (i.e., the lowest address we'll use)
VADD.I32 Q1, Q0, Q9 @ Q1 = <14|12|10| 8>*source_dx_q16+source_x0_q16
VDUP.I32 Q9, r8 @ Q8 = < 1| 1| 1| 1>*source_dx_q16
VADD.I32 Q2, Q0, Q9 @ Q2 = < 7| 5| 3| 1>*source_dx_q16+source_x0_q16
VADD.I32 Q3, Q1, Q9 @ Q3 = <15|13|11| 9>*source_dx_q16+source_x0_q16
VLD1.64 {D30,D31},[r14,:128] @ Load some constants
VMOV.I8 D28,#52
VMOV.I8 D29,#129
@ The basic idea here is to do aligned loads of a block of data and then
@ index into it using VTBL to extract the data from the source X
@ coordinate corresponding to each destination pixel.
@ This is significantly less code and significantly fewer cycles than doing
@ a series of single-lane loads, but it means that the X step between
@ pixels must be limited to 2.0 or less, otherwise we couldn't guarantee
@ that we could read 8 pixels from a single aligned 32-byte block of data.
@ Q0...Q3 contain the 16.16 fixed-point X coordinates of each pixel,
@ separated into even pixels and odd pixels to make extracting offsets and
@ weights easier.
@ We then pull out two bytes from the middle of each coordinate: the top
@ byte corresponds to the integer part of the X coordinate, and the bottom
@ byte corresponds to the weight to use for bilinear blending.
@ These are separated out into different registers with VTRN.
@ Then by subtracting the integer X coordinate of the first pixel in the
@ data block we loaded, we produce an index register suitable for use by
@ VTBL.
s42xbily_neon_loop:
@ Load the Y' data.
MOV r12,r7, ASR #16
VRSHRN.S32 D16,Q0, #8
AND r12,r12,#~15 @ Read 16-byte aligned blocks
VDUP.I8 D20,r12
ADD r12,r1, r12 @ r12 = y_row+(source_x&~7)
VRSHRN.S32 D17,Q1, #8
PLD [r12,#64]
VLD1.64 {D8, D9, D10,D11},[r12,:128],r5 @ Load Y' top row
ADD r14,r7, r8, LSL #3
VRSHRN.S32 D18,Q2, #8
MOV r14,r14,ASR #16
VRSHRN.S32 D19,Q3, #8
AND r14,r14,#~15 @ Read 16-byte aligned blocks
VLD1.64 {D12,D13,D14,D15},[r12,:128] @ Load Y' bottom row
PLD [r12,#64]
VDUP.I8 D21,r14
ADD r14,r1, r14 @ r14 = y_row+(source_x&~7)
VMOV.I8 Q13,#1
PLD [r14,#64]
VTRN.8 Q8, Q9 @ Q8 = <wFwEwDwCwBwAw9w8w7w6w5w4w3w2w1w0>
@ Q9 = <xFxExDxCxBxAx9x8x7x6x5x4x3x2x1x0>
VSUB.S8 Q9, Q9, Q10 @ Make offsets relative to the data we loaded.
@ First 8 Y' pixels
VTBL.8 D20,{D8, D9, D10,D11},D18 @ Index top row at source_x
VTBL.8 D24,{D12,D13,D14,D15},D18 @ Index bottom row at source_x
VADD.S8 Q13,Q9, Q13 @ Add 1 to source_x
VTBL.8 D22,{D8, D9, D10,D11},D26 @ Index top row at source_x+1
VTBL.8 D26,{D12,D13,D14,D15},D26 @ Index bottom row at source_x+1
@ Next 8 Y' pixels
VLD1.64 {D8, D9, D10,D11},[r14,:128],r5 @ Load Y' top row
VLD1.64 {D12,D13,D14,D15},[r14,:128] @ Load Y' bottom row
PLD [r14,#64]
VTBL.8 D21,{D8, D9, D10,D11},D19 @ Index top row at source_x
VTBL.8 D25,{D12,D13,D14,D15},D19 @ Index bottom row at source_x
VTBL.8 D23,{D8, D9, D10,D11},D27 @ Index top row at source_x+1
VTBL.8 D27,{D12,D13,D14,D15},D27 @ Index bottom row at source_x+1
@ Blend Y'.
VDUP.I16 Q9, r4 @ Load the y weights.
VSUBL.U8 Q4, D24,D20 @ Q5:Q4 = c-a
VSUBL.U8 Q5, D25,D21
VSUBL.U8 Q6, D26,D22 @ Q7:Q6 = d-b
VSUBL.U8 Q7, D27,D23
VMUL.S16 Q4, Q4, Q9 @ Q5:Q4 = (c-a)*yweight
VMUL.S16 Q5, Q5, Q9
VMUL.S16 Q6, Q6, Q9 @ Q7:Q6 = (d-b)*yweight
VMUL.S16 Q7, Q7, Q9
VMOVL.U8 Q12,D16 @ Promote the x weights to 16 bits.
VMOVL.U8 Q13,D17 @ Sadly, there's no VMULW.
VRSHRN.S16 D8, Q4, #8 @ Q4 = (c-a)*yweight+128>>8
VRSHRN.S16 D9, Q5, #8
VRSHRN.S16 D12,Q6, #8 @ Q6 = (d-b)*yweight+128>>8
VRSHRN.S16 D13,Q7, #8
VADD.I8 Q10,Q10,Q4 @ Q10 = a+((c-a)*yweight+128>>8)
VADD.I8 Q11,Q11,Q6 @ Q11 = b+((d-b)*yweight+128>>8)
VSUBL.U8 Q4, D22,D20 @ Q5:Q4 = b-a
VSUBL.U8 Q5, D23,D21
VMUL.S16 Q4, Q4, Q12 @ Q5:Q4 = (b-a)*xweight
VMUL.S16 Q5, Q5, Q13
VRSHRN.S16 D8, Q4, #8 @ Q4 = (b-a)*xweight+128>>8
ADD r12,r7, r9
VRSHRN.S16 D9, Q5, #8
MOV r12,r12,ASR #17
VADD.I8 Q8, Q10,Q4 @ Q8 = a+((b-a)*xweight+128>>8)
@ Start extracting the chroma x coordinates, and load Cb and Cr.
AND r12,r12,#~15 @ Read 16-byte aligned blocks
VDUP.I32 Q9, r9 @ Q9 = source_uv_xoffs_q16 x 4
ADD r14,r2, r12
VADD.I32 Q10,Q0, Q9
VLD1.64 {D8, D9, D10,D11},[r14,:128] @ Load Cb
PLD [r14,#64]
VADD.I32 Q11,Q1, Q9
ADD r14,r3, r12
VADD.I32 Q12,Q2, Q9
VLD1.64 {D12,D13,D14,D15},[r14,:128] @ Load Cr
PLD [r14,#64]
VADD.I32 Q13,Q3, Q9
VRSHRN.S32 D20,Q10,#9 @ Q10 = <xEwExCwCxAwAx8w8x6w6x4w4x2w2x0w0>
VRSHRN.S32 D21,Q11,#9
VDUP.I8 Q9, r12
VRSHRN.S32 D22,Q12,#9 @ Q11 = <xFwFxDwDxBwBx9w9x7w7x5w5x3w3x1w1>
VRSHRN.S32 D23,Q13,#9
@ We don't actually need the x weights, but we get them for free.
@ Free ALU slot
VTRN.8 Q10,Q11 @ Q10 = <wFwEwDwCwBwAw9w8w7w6w5w4w3w2w1w0>
@ Free ALU slot @ Q11 = <xFxExDxCxBxAx9x8x7x6x5x4x3x2x1x0>
VSUB.S8 Q11,Q11,Q9 @ Make offsets relative to the data we loaded.
VTBL.8 D18,{D8, D9, D10,D11},D22 @ Index Cb at source_x
VMOV.I8 D24,#74
VTBL.8 D19,{D8, D9, D10,D11},D23
VMOV.I8 D26,#102
VTBL.8 D20,{D12,D13,D14,D15},D22 @ Index Cr at source_x
VMOV.I8 D27,#25
VTBL.8 D21,{D12,D13,D14,D15},D23
@ We now have Y' in Q8, Cb in Q9, and Cr in Q10
@ We use VDUP to expand constants, because it's a permute instruction, so
@ it can dual issue on the A8.
SUBS r6, r6, #16 @ width -= 16
VMULL.U8 Q4, D16,D24 @ Q5:Q4 = Y'*74
VDUP.32 Q6, D30[1] @ Q7:Q6 = bias_G
VMULL.U8 Q5, D17,D24
VDUP.32 Q7, D30[1]
VMLSL.U8 Q6, D18,D27 @ Q7:Q6 = -25*Cb+bias_G
VDUP.32 Q11,D30[0] @ Q12:Q11 = bias_R
VMLSL.U8 Q7, D19,D27
VDUP.32 Q12,D30[0]
VMLAL.U8 Q11,D20,D26 @ Q12:Q11 = 102*Cr+bias_R
VDUP.32 Q8, D31[0] @ Q13:Q8 = bias_B
VMLAL.U8 Q12,D21,D26
VDUP.32 Q13,D31[0]
VMLAL.U8 Q8, D18,D29 @ Q13:Q8 = 129*Cb+bias_B
VMLAL.U8 Q13,D19,D29
VMLSL.U8 Q6, D20,D28 @ Q7:Q6 = -25*Cb-52*Cr+bias_G
VMLSL.U8 Q7, D21,D28
VADD.S16 Q11,Q4, Q11 @ Q12:Q11 = 74*Y'+102*Cr+bias_R
VADD.S16 Q12,Q5, Q12
VQADD.S16 Q8, Q4, Q8 @ Q13:Q8 = 74*Y'+129*Cr+bias_B
VQADD.S16 Q13,Q5, Q13
VADD.S16 Q6, Q4, Q6 @ Q7:Q6 = 74*Y'-25*Cb-52*Cr+bias_G
VADD.S16 Q7, Q5, Q7
@ Push each value to the top of its word and saturate it.
VQSHLU.S16 Q11,Q11,#2
VQSHLU.S16 Q12,Q12,#2
VQSHLU.S16 Q6, Q6, #2
VQSHLU.S16 Q7, Q7, #2
VQSHLU.S16 Q8, Q8, #2
VQSHLU.S16 Q13,Q13,#2
@ Merge G and B into R.
VSRI.U16 Q11,Q6, #5
VSRI.U16 Q12,Q7, #5
VSRI.U16 Q11,Q8, #11
MOV r14,r8, LSL #4
VSRI.U16 Q12,Q13,#11
BLT s42xbily_neon_tail
VDUP.I32 Q13,r14
@ Store the result.
VST1.16 {D22,D23,D24,D25},[r0]!
BEQ s42xbily_neon_done
@ Advance the x coordinates.
VADD.I32 Q0, Q0, Q13
VADD.I32 Q1, Q1, Q13
ADD r7, r14
VADD.I32 Q2, Q2, Q13
VADD.I32 Q3, Q3, Q13
B s42xbily_neon_loop
s42xbily_neon_tail:
@ We have between 1 and 15 pixels left to write.
@ -r6 == the number of pixels we need to skip writing.
@ Adjust r0 to point to the last one we need to write, because we're going
@ to write them in reverse order.
ADD r0, r0, r6, LSL #1
MOV r14,#-2
ADD r0, r0, #30
@ Skip past the ones we don't need to write.
SUB PC, PC, r6, LSL #2
ORR r0, r0, r0
VST1.16 {D25[3]},[r0,:16],r14
VST1.16 {D25[2]},[r0,:16],r14
VST1.16 {D25[1]},[r0,:16],r14
VST1.16 {D25[0]},[r0,:16],r14
VST1.16 {D24[3]},[r0,:16],r14
VST1.16 {D24[2]},[r0,:16],r14
VST1.16 {D24[1]},[r0,:16],r14
VST1.16 {D24[0]},[r0,:16],r14
VST1.16 {D23[3]},[r0,:16],r14
VST1.16 {D23[2]},[r0,:16],r14
VST1.16 {D23[1]},[r0,:16],r14
VST1.16 {D23[0]},[r0,:16],r14
VST1.16 {D22[3]},[r0,:16],r14
VST1.16 {D22[2]},[r0,:16],r14
VST1.16 {D22[1]},[r0,:16],r14
VST1.16 {D22[0]},[r0,:16]
s42xbily_neon_done:
VPOP {Q4-Q7} @ 16 words.
LDMFD r13!,{r4-r9,PC} @ 8 words.
.fnend
.size ScaleYCbCr42xToRGB565_BilinearY_Row_NEON, .-ScaleYCbCr42xToRGB565_BilinearY_Row_NEON
#if defined(__ELF__)&&defined(__linux__)
.section .note.GNU-stack,"",%progbits
#endif