/*
* Copyright 2012 The Android Open Source Project
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkBlitRow_opts_arm.h"
#include "SkBlitMask.h"
#include "SkBlitRow.h"
#include "SkColorPriv.h"
#include "SkDither.h"
#include "SkMathPriv.h"
#include "SkUtils.h"
#include "SkCachePreload_arm.h"
#include <arm_neon.h>
void S32A_D565_Opaque_neon(uint16_t* SK_RESTRICT dst,
const SkPMColor* SK_RESTRICT src, int count,
U8CPU alpha, int /*x*/, int /*y*/) {
SkASSERT(255 == alpha);
if (count >= 8) {
uint16_t* SK_RESTRICT keep_dst;
asm volatile (
"ands ip, %[count], #7 \n\t"
"vmov.u8 d31, #1<<7 \n\t"
"vld1.16 {q12}, [%[dst]] \n\t"
"vld4.8 {d0-d3}, [%[src]] \n\t"
// Thumb does not support the standard ARM conditional
// instructions but instead requires the 'it' instruction
// to signal conditional execution
"it eq \n\t"
"moveq ip, #8 \n\t"
"mov %[keep_dst], %[dst] \n\t"
"add %[src], %[src], ip, LSL#2 \n\t"
"add %[dst], %[dst], ip, LSL#1 \n\t"
"subs %[count], %[count], ip \n\t"
"b 9f \n\t"
// LOOP
"2: \n\t"
"vld1.16 {q12}, [%[dst]]! \n\t"
"vld4.8 {d0-d3}, [%[src]]! \n\t"
"vst1.16 {q10}, [%[keep_dst]] \n\t"
"sub %[keep_dst], %[dst], #8*2 \n\t"
"subs %[count], %[count], #8 \n\t"
"9: \n\t"
"pld [%[dst],#32] \n\t"
// expand 0565 q12 to 8888 {d4-d7}
"vmovn.u16 d4, q12 \n\t"
"vshr.u16 q11, q12, #5 \n\t"
"vshr.u16 q10, q12, #6+5 \n\t"
"vmovn.u16 d5, q11 \n\t"
"vmovn.u16 d6, q10 \n\t"
"vshl.u8 d4, d4, #3 \n\t"
"vshl.u8 d5, d5, #2 \n\t"
"vshl.u8 d6, d6, #3 \n\t"
"vmovl.u8 q14, d31 \n\t"
"vmovl.u8 q13, d31 \n\t"
"vmovl.u8 q12, d31 \n\t"
// duplicate in 4/2/1 & 8pix vsns
"vmvn.8 d30, d3 \n\t"
"vmlal.u8 q14, d30, d6 \n\t"
"vmlal.u8 q13, d30, d5 \n\t"
"vmlal.u8 q12, d30, d4 \n\t"
"vshr.u16 q8, q14, #5 \n\t"
"vshr.u16 q9, q13, #6 \n\t"
"vaddhn.u16 d6, q14, q8 \n\t"
"vshr.u16 q8, q12, #5 \n\t"
"vaddhn.u16 d5, q13, q9 \n\t"
"vqadd.u8 d6, d6, d0 \n\t" // moved up
"vaddhn.u16 d4, q12, q8 \n\t"
// intentionally don't calculate alpha
// result in d4-d6
"vqadd.u8 d5, d5, d1 \n\t"
"vqadd.u8 d4, d4, d2 \n\t"
// pack 8888 {d4-d6} to 0565 q10
"vshll.u8 q10, d6, #8 \n\t"
"vshll.u8 q3, d5, #8 \n\t"
"vshll.u8 q2, d4, #8 \n\t"
"vsri.u16 q10, q3, #5 \n\t"
"vsri.u16 q10, q2, #11 \n\t"
"bne 2b \n\t"
"1: \n\t"
"vst1.16 {q10}, [%[keep_dst]] \n\t"
: [count] "+r" (count)
: [dst] "r" (dst), [keep_dst] "r" (keep_dst), [src] "r" (src)
: "ip", "cc", "memory", "d0","d1","d2","d3","d4","d5","d6","d7",
"d16","d17","d18","d19","d20","d21","d22","d23","d24","d25","d26","d27","d28","d29",
"d30","d31"
);
}
else
{ // handle count < 8
uint16_t* SK_RESTRICT keep_dst;
asm volatile (
"vmov.u8 d31, #1<<7 \n\t"
"mov %[keep_dst], %[dst] \n\t"
"tst %[count], #4 \n\t"
"beq 14f \n\t"
"vld1.16 {d25}, [%[dst]]! \n\t"
"vld1.32 {q1}, [%[src]]! \n\t"
"14: \n\t"
"tst %[count], #2 \n\t"
"beq 12f \n\t"
"vld1.32 {d24[1]}, [%[dst]]! \n\t"
"vld1.32 {d1}, [%[src]]! \n\t"
"12: \n\t"
"tst %[count], #1 \n\t"
"beq 11f \n\t"
"vld1.16 {d24[1]}, [%[dst]]! \n\t"
"vld1.32 {d0[1]}, [%[src]]! \n\t"
"11: \n\t"
// unzips achieve the same as a vld4 operation
"vuzpq.u16 q0, q1 \n\t"
"vuzp.u8 d0, d1 \n\t"
"vuzp.u8 d2, d3 \n\t"
// expand 0565 q12 to 8888 {d4-d7}
"vmovn.u16 d4, q12 \n\t"
"vshr.u16 q11, q12, #5 \n\t"
"vshr.u16 q10, q12, #6+5 \n\t"
"vmovn.u16 d5, q11 \n\t"
"vmovn.u16 d6, q10 \n\t"
"vshl.u8 d4, d4, #3 \n\t"
"vshl.u8 d5, d5, #2 \n\t"
"vshl.u8 d6, d6, #3 \n\t"
"vmovl.u8 q14, d31 \n\t"
"vmovl.u8 q13, d31 \n\t"
"vmovl.u8 q12, d31 \n\t"
// duplicate in 4/2/1 & 8pix vsns
"vmvn.8 d30, d3 \n\t"
"vmlal.u8 q14, d30, d6 \n\t"
"vmlal.u8 q13, d30, d5 \n\t"
"vmlal.u8 q12, d30, d4 \n\t"
"vshr.u16 q8, q14, #5 \n\t"
"vshr.u16 q9, q13, #6 \n\t"
"vaddhn.u16 d6, q14, q8 \n\t"
"vshr.u16 q8, q12, #5 \n\t"
"vaddhn.u16 d5, q13, q9 \n\t"
"vqadd.u8 d6, d6, d0 \n\t" // moved up
"vaddhn.u16 d4, q12, q8 \n\t"
// intentionally don't calculate alpha
// result in d4-d6
"vqadd.u8 d5, d5, d1 \n\t"
"vqadd.u8 d4, d4, d2 \n\t"
// pack 8888 {d4-d6} to 0565 q10
"vshll.u8 q10, d6, #8 \n\t"
"vshll.u8 q3, d5, #8 \n\t"
"vshll.u8 q2, d4, #8 \n\t"
"vsri.u16 q10, q3, #5 \n\t"
"vsri.u16 q10, q2, #11 \n\t"
// store
"tst %[count], #4 \n\t"
"beq 24f \n\t"
"vst1.16 {d21}, [%[keep_dst]]! \n\t"
"24: \n\t"
"tst %[count], #2 \n\t"
"beq 22f \n\t"
"vst1.32 {d20[1]}, [%[keep_dst]]! \n\t"
"22: \n\t"
"tst %[count], #1 \n\t"
"beq 21f \n\t"
"vst1.16 {d20[1]}, [%[keep_dst]]! \n\t"
"21: \n\t"
: [count] "+r" (count)
: [dst] "r" (dst), [keep_dst] "r" (keep_dst), [src] "r" (src)
: "ip", "cc", "memory", "d0","d1","d2","d3","d4","d5","d6","d7",
"d16","d17","d18","d19","d20","d21","d22","d23","d24","d25","d26","d27","d28","d29",
"d30","d31"
);
}
}
void S32A_D565_Blend_neon(uint16_t* SK_RESTRICT dst,
const SkPMColor* SK_RESTRICT src, int count,
U8CPU alpha, int /*x*/, int /*y*/) {
U8CPU alpha_for_asm = alpha;
asm volatile (
/* This code implements a Neon version of S32A_D565_Blend. The output differs from
* the original in two respects:
* 1. The results have a few mismatches compared to the original code. These mismatches
* never exceed 1. It's possible to improve accuracy vs. a floating point
* implementation by introducing rounding right shifts (vrshr) for the final stage.
* Rounding is not present in the code below, because although results would be closer
* to a floating point implementation, the number of mismatches compared to the
* original code would be far greater.
* 2. On certain inputs, the original code can overflow, causing colour channels to
* mix. Although the Neon code can also overflow, it doesn't allow one colour channel
* to affect another.
*/
#if 1
/* reflects SkAlpha255To256()'s change from a+a>>7 to a+1 */
"add %[alpha], %[alpha], #1 \n\t" // adjust range of alpha 0-256
#else
"add %[alpha], %[alpha], %[alpha], lsr #7 \n\t" // adjust range of alpha 0-256
#endif
"vmov.u16 q3, #255 \n\t" // set up constant
"movs r4, %[count], lsr #3 \n\t" // calc. count>>3
"vmov.u16 d2[0], %[alpha] \n\t" // move alpha to Neon
"beq 2f \n\t" // if count8 == 0, exit
"vmov.u16 q15, #0x1f \n\t" // set up blue mask
"1: \n\t"
"vld1.u16 {d0, d1}, [%[dst]] \n\t" // load eight dst RGB565 pixels
"subs r4, r4, #1 \n\t" // decrement loop counter
"vld4.u8 {d24, d25, d26, d27}, [%[src]]! \n\t" // load eight src ABGR32 pixels
// and deinterleave
"vshl.u16 q9, q0, #5 \n\t" // shift green to top of lanes
"vand q10, q0, q15 \n\t" // extract blue
"vshr.u16 q8, q0, #11 \n\t" // extract red
"vshr.u16 q9, q9, #10 \n\t" // extract green
// dstrgb = {q8, q9, q10}
"vshr.u8 d24, d24, #3 \n\t" // shift red to 565 range
"vshr.u8 d25, d25, #2 \n\t" // shift green to 565 range
"vshr.u8 d26, d26, #3 \n\t" // shift blue to 565 range
"vmovl.u8 q11, d24 \n\t" // widen red to 16 bits
"vmovl.u8 q12, d25 \n\t" // widen green to 16 bits
"vmovl.u8 q14, d27 \n\t" // widen alpha to 16 bits
"vmovl.u8 q13, d26 \n\t" // widen blue to 16 bits
// srcrgba = {q11, q12, q13, q14}
"vmul.u16 q2, q14, d2[0] \n\t" // sa * src_scale
"vmul.u16 q11, q11, d2[0] \n\t" // red result = src_red * src_scale
"vmul.u16 q12, q12, d2[0] \n\t" // grn result = src_grn * src_scale
"vmul.u16 q13, q13, d2[0] \n\t" // blu result = src_blu * src_scale
"vshr.u16 q2, q2, #8 \n\t" // sa * src_scale >> 8
"vsub.u16 q2, q3, q2 \n\t" // 255 - (sa * src_scale >> 8)
// dst_scale = q2
"vmla.u16 q11, q8, q2 \n\t" // red result += dst_red * dst_scale
"vmla.u16 q12, q9, q2 \n\t" // grn result += dst_grn * dst_scale
"vmla.u16 q13, q10, q2 \n\t" // blu result += dst_blu * dst_scale
#if 1
// trying for a better match with SkDiv255Round(a)
// C alg is: a+=128; (a+a>>8)>>8
// we'll use just a rounding shift [q2 is available for scratch]
"vrshr.u16 q11, q11, #8 \n\t" // shift down red
"vrshr.u16 q12, q12, #8 \n\t" // shift down green
"vrshr.u16 q13, q13, #8 \n\t" // shift down blue
#else
// arm's original "truncating divide by 256"
"vshr.u16 q11, q11, #8 \n\t" // shift down red
"vshr.u16 q12, q12, #8 \n\t" // shift down green
"vshr.u16 q13, q13, #8 \n\t" // shift down blue
#endif
"vsli.u16 q13, q12, #5 \n\t" // insert green into blue
"vsli.u16 q13, q11, #11 \n\t" // insert red into green/blue
"vst1.16 {d26, d27}, [%[dst]]! \n\t" // write pixel back to dst, update ptr
"bne 1b \n\t" // if counter != 0, loop
"2: \n\t" // exit
: [src] "+r" (src), [dst] "+r" (dst), [count] "+r" (count), [alpha] "+r" (alpha_for_asm)
:
: "cc", "memory", "r4", "d0", "d1", "d2", "d3", "d4", "d5", "d6", "d7", "d16", "d17", "d18", "d19", "d20", "d21", "d22", "d23", "d24", "d25", "d26", "d27", "d28", "d29", "d30", "d31"
);
count &= 7;
if (count > 0) {
do {
SkPMColor sc = *src++;
if (sc) {
uint16_t dc = *dst;
unsigned dst_scale = 255 - SkMulDiv255Round(SkGetPackedA32(sc), alpha);
unsigned dr = SkMulS16(SkPacked32ToR16(sc), alpha) + SkMulS16(SkGetPackedR16(dc), dst_scale);
unsigned dg = SkMulS16(SkPacked32ToG16(sc), alpha) + SkMulS16(SkGetPackedG16(dc), dst_scale);
unsigned db = SkMulS16(SkPacked32ToB16(sc), alpha) + SkMulS16(SkGetPackedB16(dc), dst_scale);
*dst = SkPackRGB16(SkDiv255Round(dr), SkDiv255Round(dg), SkDiv255Round(db));
}
dst += 1;
} while (--count != 0);
}
}
/* dither matrix for Neon, derived from gDitherMatrix_3Bit_16.
* each dither value is spaced out into byte lanes, and repeated
* to allow an 8-byte load from offsets 0, 1, 2 or 3 from the
* start of each row.
*/
static const uint8_t gDitherMatrix_Neon[48] = {
0, 4, 1, 5, 0, 4, 1, 5, 0, 4, 1, 5,
6, 2, 7, 3, 6, 2, 7, 3, 6, 2, 7, 3,
1, 5, 0, 4, 1, 5, 0, 4, 1, 5, 0, 4,
7, 3, 6, 2, 7, 3, 6, 2, 7, 3, 6, 2,
};
void S32_D565_Blend_Dither_neon(uint16_t *dst, const SkPMColor *src,
int count, U8CPU alpha, int x, int y)
{
/* select row and offset for dither array */
const uint8_t *dstart = &gDitherMatrix_Neon[(y&3)*12 + (x&3)];
/* rescale alpha to range 0 - 256 */
int scale = SkAlpha255To256(alpha);
asm volatile (
"vld1.8 {d31}, [%[dstart]] \n\t" // load dither values
"vshr.u8 d30, d31, #1 \n\t" // calc. green dither values
"vdup.16 d6, %[scale] \n\t" // duplicate scale into neon reg
"vmov.i8 d29, #0x3f \n\t" // set up green mask
"vmov.i8 d28, #0x1f \n\t" // set up blue mask
"1: \n\t"
"vld4.8 {d0, d1, d2, d3}, [%[src]]! \n\t" // load 8 pixels and split into argb
"vshr.u8 d22, d0, #5 \n\t" // calc. red >> 5
"vshr.u8 d23, d1, #6 \n\t" // calc. green >> 6
"vshr.u8 d24, d2, #5 \n\t" // calc. blue >> 5
"vaddl.u8 q8, d0, d31 \n\t" // add in dither to red and widen
"vaddl.u8 q9, d1, d30 \n\t" // add in dither to green and widen
"vaddl.u8 q10, d2, d31 \n\t" // add in dither to blue and widen
"vsubw.u8 q8, q8, d22 \n\t" // sub shifted red from result
"vsubw.u8 q9, q9, d23 \n\t" // sub shifted green from result
"vsubw.u8 q10, q10, d24 \n\t" // sub shifted blue from result
"vshrn.i16 d22, q8, #3 \n\t" // shift right and narrow to 5 bits
"vshrn.i16 d23, q9, #2 \n\t" // shift right and narrow to 6 bits
"vshrn.i16 d24, q10, #3 \n\t" // shift right and narrow to 5 bits
// load 8 pixels from dst, extract rgb
"vld1.16 {d0, d1}, [%[dst]] \n\t" // load 8 pixels
"vshrn.i16 d17, q0, #5 \n\t" // shift green down to bottom 6 bits
"vmovn.i16 d18, q0 \n\t" // narrow to get blue as bytes
"vshr.u16 q0, q0, #11 \n\t" // shift down to extract red
"vand d17, d17, d29 \n\t" // and green with green mask
"vand d18, d18, d28 \n\t" // and blue with blue mask
"vmovn.i16 d16, q0 \n\t" // narrow to get red as bytes
// src = {d22 (r), d23 (g), d24 (b)}
// dst = {d16 (r), d17 (g), d18 (b)}
// subtract dst from src and widen
"vsubl.s8 q0, d22, d16 \n\t" // subtract red src from dst
"vsubl.s8 q1, d23, d17 \n\t" // subtract green src from dst
"vsubl.s8 q2, d24, d18 \n\t" // subtract blue src from dst
// multiply diffs by scale and shift
"vmul.i16 q0, q0, d6[0] \n\t" // multiply red by scale
"vmul.i16 q1, q1, d6[0] \n\t" // multiply blue by scale
"vmul.i16 q2, q2, d6[0] \n\t" // multiply green by scale
"subs %[count], %[count], #8 \n\t" // decrement loop counter
"vshrn.i16 d0, q0, #8 \n\t" // shift down red by 8 and narrow
"vshrn.i16 d2, q1, #8 \n\t" // shift down green by 8 and narrow
"vshrn.i16 d4, q2, #8 \n\t" // shift down blue by 8 and narrow
// add dst to result
"vaddl.s8 q0, d0, d16 \n\t" // add dst to red
"vaddl.s8 q1, d2, d17 \n\t" // add dst to green
"vaddl.s8 q2, d4, d18 \n\t" // add dst to blue
// put result into 565 format
"vsli.i16 q2, q1, #5 \n\t" // shift up green and insert into blue
"vsli.i16 q2, q0, #11 \n\t" // shift up red and insert into blue
"vst1.16 {d4, d5}, [%[dst]]! \n\t" // store result
"bgt 1b \n\t" // loop if count > 0
: [src] "+r" (src), [dst] "+r" (dst), [count] "+r" (count)
: [dstart] "r" (dstart), [scale] "r" (scale)
: "cc", "memory", "d0", "d1", "d2", "d3", "d4", "d5", "d6", "d16", "d17", "d18", "d19", "d20", "d21", "d22", "d23", "d24", "d28", "d29", "d30", "d31"
);
DITHER_565_SCAN(y);
while((count & 7) > 0)
{
SkPMColor c = *src++;
int dither = DITHER_VALUE(x);
int sr = SkGetPackedR32(c);
int sg = SkGetPackedG32(c);
int sb = SkGetPackedB32(c);
sr = SkDITHER_R32To565(sr, dither);
sg = SkDITHER_G32To565(sg, dither);
sb = SkDITHER_B32To565(sb, dither);
uint16_t d = *dst;
*dst++ = SkPackRGB16(SkAlphaBlend(sr, SkGetPackedR16(d), scale),
SkAlphaBlend(sg, SkGetPackedG16(d), scale),
SkAlphaBlend(sb, SkGetPackedB16(d), scale));
DITHER_INC_X(x);
count--;
}
}
void S32A_Opaque_BlitRow32_neon(SkPMColor* SK_RESTRICT dst,
const SkPMColor* SK_RESTRICT src,
int count, U8CPU alpha) {
SkASSERT(255 == alpha);
if (count > 0) {
uint8x8_t alpha_mask;
static const uint8_t alpha_mask_setup[] = {3,3,3,3,7,7,7,7};
alpha_mask = vld1_u8(alpha_mask_setup);
/* do the NEON unrolled code */
#define UNROLL 4
while (count >= UNROLL) {
uint8x8_t src_raw, dst_raw, dst_final;
uint8x8_t src_raw_2, dst_raw_2, dst_final_2;
/* get the source */
src_raw = vreinterpret_u8_u32(vld1_u32(src));
#if UNROLL > 2
src_raw_2 = vreinterpret_u8_u32(vld1_u32(src+2));
#endif
/* get and hold the dst too */
dst_raw = vreinterpret_u8_u32(vld1_u32(dst));
#if UNROLL > 2
dst_raw_2 = vreinterpret_u8_u32(vld1_u32(dst+2));
#endif
/* 1st and 2nd bits of the unrolling */
{
uint8x8_t dst_cooked;
uint16x8_t dst_wide;
uint8x8_t alpha_narrow;
uint16x8_t alpha_wide;
/* get the alphas spread out properly */
alpha_narrow = vtbl1_u8(src_raw, alpha_mask);
#if 1
/* reflect SkAlpha255To256() semantics a+1 vs a+a>>7 */
/* we collapsed (255-a)+1 ... */
alpha_wide = vsubw_u8(vdupq_n_u16(256), alpha_narrow);
#else
alpha_wide = vsubw_u8(vdupq_n_u16(255), alpha_narrow);
alpha_wide = vaddq_u16(alpha_wide, vshrq_n_u16(alpha_wide,7));
#endif
/* spread the dest */
dst_wide = vmovl_u8(dst_raw);
/* alpha mul the dest */
dst_wide = vmulq_u16 (dst_wide, alpha_wide);
dst_cooked = vshrn_n_u16(dst_wide, 8);
/* sum -- ignoring any byte lane overflows */
dst_final = vadd_u8(src_raw, dst_cooked);
}
#if UNROLL > 2
/* the 3rd and 4th bits of our unrolling */
{
uint8x8_t dst_cooked;
uint16x8_t dst_wide;
uint8x8_t alpha_narrow;
uint16x8_t alpha_wide;
alpha_narrow = vtbl1_u8(src_raw_2, alpha_mask);
#if 1
/* reflect SkAlpha255To256() semantics a+1 vs a+a>>7 */
/* we collapsed (255-a)+1 ... */
alpha_wide = vsubw_u8(vdupq_n_u16(256), alpha_narrow);
#else
alpha_wide = vsubw_u8(vdupq_n_u16(255), alpha_narrow);
alpha_wide = vaddq_u16(alpha_wide, vshrq_n_u16(alpha_wide,7));
#endif
/* spread the dest */
dst_wide = vmovl_u8(dst_raw_2);
/* alpha mul the dest */
dst_wide = vmulq_u16 (dst_wide, alpha_wide);
dst_cooked = vshrn_n_u16(dst_wide, 8);
/* sum -- ignoring any byte lane overflows */
dst_final_2 = vadd_u8(src_raw_2, dst_cooked);
}
#endif
vst1_u32(dst, vreinterpret_u32_u8(dst_final));
#if UNROLL > 2
vst1_u32(dst+2, vreinterpret_u32_u8(dst_final_2));
#endif
src += UNROLL;
dst += UNROLL;
count -= UNROLL;
}
#undef UNROLL
/* do any residual iterations */
while (--count >= 0) {
*dst = SkPMSrcOver(*src, *dst);
src += 1;
dst += 1;
}
}
}
/* Neon version of S32_Blend_BlitRow32()
* portable version is in src/core/SkBlitRow_D32.cpp
*/
void S32_Blend_BlitRow32_neon(SkPMColor* SK_RESTRICT dst,
const SkPMColor* SK_RESTRICT src,
int count, U8CPU alpha) {
SkASSERT(alpha <= 255);
if (count > 0) {
uint16_t src_scale = SkAlpha255To256(alpha);
uint16_t dst_scale = 256 - src_scale;
/* run them N at a time through the NEON unit */
/* note that each 1 is 4 bytes, each treated exactly the same,
* so we can work under that guise. We *do* know that the src&dst
* will be 32-bit aligned quantities, so we can specify that on
* the load/store ops and do a neon 'reinterpret' to get us to
* byte-sized (pun intended) pieces that we widen/multiply/shift
* we're limited at 128 bits in the wide ops, which is 8x16bits
* or a pair of 32 bit src/dsts.
*/
/* we *could* manually unroll this loop so that we load 128 bits
* (as a pair of 64s) from each of src and dst, processing them
* in pieces. This might give us a little better management of
* the memory latency, but my initial attempts here did not
* produce an instruction stream that looked all that nice.
*/
#define UNROLL 2
while (count >= UNROLL) {
uint8x8_t src_raw, dst_raw, dst_final;
uint16x8_t src_wide, dst_wide;
/* get 64 bits of src, widen it, multiply by src_scale */
src_raw = vreinterpret_u8_u32(vld1_u32(src));
src_wide = vmovl_u8(src_raw);
/* gcc hoists vdupq_n_u16(), better than using vmulq_n_u16() */
src_wide = vmulq_u16 (src_wide, vdupq_n_u16(src_scale));
/* ditto with dst */
dst_raw = vreinterpret_u8_u32(vld1_u32(dst));
dst_wide = vmovl_u8(dst_raw);
/* combine add with dst multiply into mul-accumulate */
dst_wide = vmlaq_u16(src_wide, dst_wide, vdupq_n_u16(dst_scale));
dst_final = vshrn_n_u16(dst_wide, 8);
vst1_u32(dst, vreinterpret_u32_u8(dst_final));
src += UNROLL;
dst += UNROLL;
count -= UNROLL;
}
/* RBE: well, i don't like how gcc manages src/dst across the above
* loop it's constantly calculating src+bias, dst+bias and it only
* adjusts the real ones when we leave the loop. Not sure why
* it's "hoisting down" (hoisting implies above in my lexicon ;))
* the adjustments to src/dst/count, but it does...
* (might be SSA-style internal logic...
*/
#if UNROLL == 2
if (count == 1) {
*dst = SkAlphaMulQ(*src, src_scale) + SkAlphaMulQ(*dst, dst_scale);
}
#else
if (count > 0) {
do {
*dst = SkAlphaMulQ(*src, src_scale) + SkAlphaMulQ(*dst, dst_scale);
src += 1;
dst += 1;
} while (--count > 0);
}
#endif
#undef UNROLL
}
}
///////////////////////////////////////////////////////////////////////////////
#undef DEBUG_OPAQUE_DITHER
#if defined(DEBUG_OPAQUE_DITHER)
static void showme8(char *str, void *p, int len)
{
static char buf[256];
char tbuf[32];
int i;
char *pc = (char*) p;
sprintf(buf,"%8s:", str);
for(i=0;i<len;i++) {
sprintf(tbuf, " %02x", pc[i]);
strcat(buf, tbuf);
}
SkDebugf("%s\n", buf);
}
static void showme16(char *str, void *p, int len)
{
static char buf[256];
char tbuf[32];
int i;
uint16_t *pc = (uint16_t*) p;
sprintf(buf,"%8s:", str);
len = (len / sizeof(uint16_t)); /* passed as bytes */
for(i=0;i<len;i++) {
sprintf(tbuf, " %04x", pc[i]);
strcat(buf, tbuf);
}
SkDebugf("%s\n", buf);
}
#endif
void S32A_D565_Opaque_Dither_neon (uint16_t * SK_RESTRICT dst,
const SkPMColor* SK_RESTRICT src,
int count, U8CPU alpha, int x, int y) {
SkASSERT(255 == alpha);
#define UNROLL 8
if (count >= UNROLL) {
uint8x8_t dbase;
#if defined(DEBUG_OPAQUE_DITHER)
uint16_t tmpbuf[UNROLL];
int td[UNROLL];
int tdv[UNROLL];
int ta[UNROLL];
int tap[UNROLL];
uint16_t in_dst[UNROLL];
int offset = 0;
int noisy = 0;
#endif
const uint8_t *dstart = &gDitherMatrix_Neon[(y&3)*12 + (x&3)];
dbase = vld1_u8(dstart);
do {
uint8x8_t sr, sg, sb, sa, d;
uint16x8_t dst8, scale8, alpha8;
uint16x8_t dst_r, dst_g, dst_b;
#if defined(DEBUG_OPAQUE_DITHER)
/* calculate 8 elements worth into a temp buffer */
{
int my_y = y;
int my_x = x;
SkPMColor* my_src = (SkPMColor*)src;
uint16_t* my_dst = dst;
int i;
DITHER_565_SCAN(my_y);
for(i=0;i<UNROLL;i++) {
SkPMColor c = *my_src++;
SkPMColorAssert(c);
if (c) {
unsigned a = SkGetPackedA32(c);
int d = SkAlphaMul(DITHER_VALUE(my_x), SkAlpha255To256(a));
tdv[i] = DITHER_VALUE(my_x);
ta[i] = a;
tap[i] = SkAlpha255To256(a);
td[i] = d;
unsigned sr = SkGetPackedR32(c);
unsigned sg = SkGetPackedG32(c);
unsigned sb = SkGetPackedB32(c);
sr = SkDITHER_R32_FOR_565(sr, d);
sg = SkDITHER_G32_FOR_565(sg, d);
sb = SkDITHER_B32_FOR_565(sb, d);
uint32_t src_expanded = (sg << 24) | (sr << 13) | (sb << 2);
uint32_t dst_expanded = SkExpand_rgb_16(*my_dst);
dst_expanded = dst_expanded * (SkAlpha255To256(255 - a) >> 3);
// now src and dst expanded are in g:11 r:10 x:1 b:10
tmpbuf[i] = SkCompact_rgb_16((src_expanded + dst_expanded) >> 5);
td[i] = d;
} else {
tmpbuf[i] = *my_dst;
ta[i] = tdv[i] = td[i] = 0xbeef;
}
in_dst[i] = *my_dst;
my_dst += 1;
DITHER_INC_X(my_x);
}
}
#endif
/* source is in ABGR */
{
register uint8x8_t d0 asm("d0");
register uint8x8_t d1 asm("d1");
register uint8x8_t d2 asm("d2");
register uint8x8_t d3 asm("d3");
asm ("vld4.8 {d0-d3},[%4] /* r=%P0 g=%P1 b=%P2 a=%P3 */"
: "=w" (d0), "=w" (d1), "=w" (d2), "=w" (d3)
: "r" (src)
);
sr = d0; sg = d1; sb = d2; sa = d3;
}
/* calculate 'd', which will be 0..7 */
/* dbase[] is 0..7; alpha is 0..256; 16 bits suffice */
#if defined(SK_BUILD_FOR_ANDROID)
/* SkAlpha255To256() semantic a+1 vs a+a>>7 */
alpha8 = vaddw_u8(vmovl_u8(sa), vdup_n_u8(1));
#else
alpha8 = vaddw_u8(vmovl_u8(sa), vshr_n_u8(sa, 7));
#endif
alpha8 = vmulq_u16(alpha8, vmovl_u8(dbase));
d = vshrn_n_u16(alpha8, 8); /* narrowing too */
/* sr = sr - (sr>>5) + d */
/* watching for 8-bit overflow. d is 0..7; risky range of
* sr is >248; and then (sr>>5) is 7 so it offsets 'd';
* safe as long as we do ((sr-sr>>5) + d) */
sr = vsub_u8(sr, vshr_n_u8(sr, 5));
sr = vadd_u8(sr, d);
/* sb = sb - (sb>>5) + d */
sb = vsub_u8(sb, vshr_n_u8(sb, 5));
sb = vadd_u8(sb, d);
/* sg = sg - (sg>>6) + d>>1; similar logic for overflows */
sg = vsub_u8(sg, vshr_n_u8(sg, 6));
sg = vadd_u8(sg, vshr_n_u8(d,1));
/* need to pick up 8 dst's -- at 16 bits each, 128 bits */
dst8 = vld1q_u16(dst);
dst_b = vandq_u16(dst8, vdupq_n_u16(0x001F));
dst_g = vandq_u16(vshrq_n_u16(dst8,5), vdupq_n_u16(0x003F));
dst_r = vshrq_n_u16(dst8,11); /* clearing hi bits */
/* blend */
#if 1
/* SkAlpha255To256() semantic a+1 vs a+a>>7 */
/* originally 255-sa + 1 */
scale8 = vsubw_u8(vdupq_n_u16(256), sa);
#else
scale8 = vsubw_u8(vdupq_n_u16(255), sa);
scale8 = vaddq_u16(scale8, vshrq_n_u16(scale8, 7));
#endif
#if 1
/* combine the addq and mul, save 3 insns */
scale8 = vshrq_n_u16(scale8, 3);
dst_b = vmlaq_u16(vshll_n_u8(sb,2), dst_b, scale8);
dst_g = vmlaq_u16(vshll_n_u8(sg,3), dst_g, scale8);
dst_r = vmlaq_u16(vshll_n_u8(sr,2), dst_r, scale8);
#else
/* known correct, but +3 insns over above */
scale8 = vshrq_n_u16(scale8, 3);
dst_b = vmulq_u16(dst_b, scale8);
dst_g = vmulq_u16(dst_g, scale8);
dst_r = vmulq_u16(dst_r, scale8);
/* combine */
/* NB: vshll widens, need to preserve those bits */
dst_b = vaddq_u16(dst_b, vshll_n_u8(sb,2));
dst_g = vaddq_u16(dst_g, vshll_n_u8(sg,3));
dst_r = vaddq_u16(dst_r, vshll_n_u8(sr,2));
#endif
/* repack to store */
dst8 = vandq_u16(vshrq_n_u16(dst_b, 5), vdupq_n_u16(0x001F));
dst8 = vsliq_n_u16(dst8, vshrq_n_u16(dst_g, 5), 5);
dst8 = vsliq_n_u16(dst8, vshrq_n_u16(dst_r,5), 11);
vst1q_u16(dst, dst8);
#if defined(DEBUG_OPAQUE_DITHER)
/* verify my 8 elements match the temp buffer */
{
int i, bad=0;
static int invocation;
for (i=0;i<UNROLL;i++)
if (tmpbuf[i] != dst[i]) bad=1;
if (bad) {
SkDebugf("BAD S32A_D565_Opaque_Dither_neon(); invocation %d offset %d\n",
invocation, offset);
SkDebugf(" alpha 0x%x\n", alpha);
for (i=0;i<UNROLL;i++)
SkDebugf("%2d: %s %04x w %04x id %04x s %08x d %04x %04x %04x %04x\n",
i, ((tmpbuf[i] != dst[i])?"BAD":"got"),
dst[i], tmpbuf[i], in_dst[i], src[i], td[i], tdv[i], tap[i], ta[i]);
showme16("alpha8", &alpha8, sizeof(alpha8));
showme16("scale8", &scale8, sizeof(scale8));
showme8("d", &d, sizeof(d));
showme16("dst8", &dst8, sizeof(dst8));
showme16("dst_b", &dst_b, sizeof(dst_b));
showme16("dst_g", &dst_g, sizeof(dst_g));
showme16("dst_r", &dst_r, sizeof(dst_r));
showme8("sb", &sb, sizeof(sb));
showme8("sg", &sg, sizeof(sg));
showme8("sr", &sr, sizeof(sr));
/* cop out */
return;
}
offset += UNROLL;
invocation++;
}
#endif
dst += UNROLL;
src += UNROLL;
count -= UNROLL;
/* skip x += UNROLL, since it's unchanged mod-4 */
} while (count >= UNROLL);
}
#undef UNROLL
/* residuals */
if (count > 0) {
DITHER_565_SCAN(y);
do {
SkPMColor c = *src++;
SkPMColorAssert(c);
if (c) {
unsigned a = SkGetPackedA32(c);
// dither and alpha are just temporary variables to work-around
// an ICE in debug.
unsigned dither = DITHER_VALUE(x);
unsigned alpha = SkAlpha255To256(a);
int d = SkAlphaMul(dither, alpha);
unsigned sr = SkGetPackedR32(c);
unsigned sg = SkGetPackedG32(c);
unsigned sb = SkGetPackedB32(c);
sr = SkDITHER_R32_FOR_565(sr, d);
sg = SkDITHER_G32_FOR_565(sg, d);
sb = SkDITHER_B32_FOR_565(sb, d);
uint32_t src_expanded = (sg << 24) | (sr << 13) | (sb << 2);
uint32_t dst_expanded = SkExpand_rgb_16(*dst);
dst_expanded = dst_expanded * (SkAlpha255To256(255 - a) >> 3);
// now src and dst expanded are in g:11 r:10 x:1 b:10
*dst = SkCompact_rgb_16((src_expanded + dst_expanded) >> 5);
}
dst += 1;
DITHER_INC_X(x);
} while (--count != 0);
}
}
///////////////////////////////////////////////////////////////////////////////
/* 2009/10/27: RBE says "a work in progress"; debugging says ok;
* speedup untested, but ARM version is 26 insns/iteration and
* this NEON version is 21 insns/iteration-of-8 (2.62insns/element)
* which is 10x the native version; that's pure instruction counts,
* not accounting for any instruction or memory latencies.
*/
#undef DEBUG_S32_OPAQUE_DITHER
void S32_D565_Opaque_Dither_neon(uint16_t* SK_RESTRICT dst,
const SkPMColor* SK_RESTRICT src,
int count, U8CPU alpha, int x, int y) {
SkASSERT(255 == alpha);
#define UNROLL 8
if (count >= UNROLL) {
uint8x8_t d;
const uint8_t *dstart = &gDitherMatrix_Neon[(y&3)*12 + (x&3)];
d = vld1_u8(dstart);
while (count >= UNROLL) {
uint8x8_t sr, sg, sb, sa;
uint16x8_t dr, dg, db, da;
uint16x8_t dst8;
/* source is in ABGR ordering (R == lsb) */
{
register uint8x8_t d0 asm("d0");
register uint8x8_t d1 asm("d1");
register uint8x8_t d2 asm("d2");
register uint8x8_t d3 asm("d3");
asm ("vld4.8 {d0-d3},[%4] /* r=%P0 g=%P1 b=%P2 a=%P3 */"
: "=w" (d0), "=w" (d1), "=w" (d2), "=w" (d3)
: "r" (src)
);
sr = d0; sg = d1; sb = d2; sa = d3;
}
/* XXX: if we want to prefetch, hide it in the above asm()
* using the gcc __builtin_prefetch(), the prefetch will
* fall to the bottom of the loop -- it won't stick up
* at the top of the loop, just after the vld4.
*/
/* sr = sr - (sr>>5) + d */
sr = vsub_u8(sr, vshr_n_u8(sr, 5));
dr = vaddl_u8(sr, d);
/* sb = sb - (sb>>5) + d */
sb = vsub_u8(sb, vshr_n_u8(sb, 5));
db = vaddl_u8(sb, d);
/* sg = sg - (sg>>6) + d>>1; similar logic for overflows */
sg = vsub_u8(sg, vshr_n_u8(sg, 6));
dg = vaddl_u8(sg, vshr_n_u8(d,1));
/* XXX: check that the "d>>1" here is hoisted */
/* pack high bits of each into 565 format (rgb, b is lsb) */
dst8 = vshrq_n_u16(db, 3);
dst8 = vsliq_n_u16(dst8, vshrq_n_u16(dg, 2), 5);
dst8 = vsliq_n_u16(dst8, vshrq_n_u16(dr,3), 11);
/* store it */
vst1q_u16(dst, dst8);
#if defined(DEBUG_S32_OPAQUE_DITHER)
/* always good to know if we generated good results */
{
int i, myx = x, myy = y;
DITHER_565_SCAN(myy);
for (i=0;i<UNROLL;i++) {
SkPMColor c = src[i];
unsigned dither = DITHER_VALUE(myx);
uint16_t val = SkDitherRGB32To565(c, dither);
if (val != dst[i]) {
SkDebugf("RBE: src %08x dither %02x, want %04x got %04x dbas[i] %02x\n",
c, dither, val, dst[i], dstart[i]);
}
DITHER_INC_X(myx);
}
}
#endif
dst += UNROLL;
src += UNROLL;
count -= UNROLL;
x += UNROLL; /* probably superfluous */
}
}
#undef UNROLL
/* residuals */
if (count > 0) {
DITHER_565_SCAN(y);
do {
SkPMColor c = *src++;
SkPMColorAssert(c);
SkASSERT(SkGetPackedA32(c) == 255);
unsigned dither = DITHER_VALUE(x);
*dst++ = SkDitherRGB32To565(c, dither);
DITHER_INC_X(x);
} while (--count != 0);
}
}
void Color32_arm_neon(SkPMColor* dst, const SkPMColor* src, int count,
SkPMColor color) {
if (count <= 0) {
return;
}
if (0 == color) {
if (src != dst) {
memcpy(dst, src, count * sizeof(SkPMColor));
}
return;
}
unsigned colorA = SkGetPackedA32(color);
if (255 == colorA) {
sk_memset32(dst, color, count);
} else {
unsigned scale = 256 - SkAlpha255To256(colorA);
if (count >= 8) {
// at the end of this assembly, count will have been decremented
// to a negative value. That is, if count mod 8 = x, it will be
// -8 +x coming out.
asm volatile (
PLD128(src, 0)
"vdup.32 q0, %[color] \n\t"
PLD128(src, 128)
// scale numerical interval [0-255], so load as 8 bits
"vdup.8 d2, %[scale] \n\t"
PLD128(src, 256)
"subs %[count], %[count], #8 \n\t"
PLD128(src, 384)
"Loop_Color32: \n\t"
// load src color, 8 pixels, 4 64 bit registers
// (and increment src).
"vld1.32 {d4-d7}, [%[src]]! \n\t"
PLD128(src, 384)
// multiply long by scale, 64 bits at a time,
// destination into a 128 bit register.
"vmull.u8 q4, d4, d2 \n\t"
"vmull.u8 q5, d5, d2 \n\t"
"vmull.u8 q6, d6, d2 \n\t"
"vmull.u8 q7, d7, d2 \n\t"
// shift the 128 bit registers, containing the 16
// bit scaled values back to 8 bits, narrowing the
// results to 64 bit registers.
"vshrn.i16 d8, q4, #8 \n\t"
"vshrn.i16 d9, q5, #8 \n\t"
"vshrn.i16 d10, q6, #8 \n\t"
"vshrn.i16 d11, q7, #8 \n\t"
// adding back the color, using 128 bit registers.
"vadd.i8 q6, q4, q0 \n\t"
"vadd.i8 q7, q5, q0 \n\t"
// store back the 8 calculated pixels (2 128 bit
// registers), and increment dst.
"vst1.32 {d12-d15}, [%[dst]]! \n\t"
"subs %[count], %[count], #8 \n\t"
"bge Loop_Color32 \n\t"
: [src] "+r" (src), [dst] "+r" (dst), [count] "+r" (count)
: [color] "r" (color), [scale] "r" (scale)
: "cc", "memory",
"d0", "d1", "d2", "d3", "d4", "d5", "d6", "d7",
"d8", "d9", "d10", "d11", "d12", "d13", "d14", "d15"
);
// At this point, if we went through the inline assembly, count is
// a negative value:
// if the value is -8, there is no pixel left to process.
// if the value is -7, there is one pixel left to process
// ...
// And'ing it with 7 will give us the number of pixels
// left to process.
count = count & 0x7;
}
while (count > 0) {
*dst = color + SkAlphaMulQ(*src, scale);
src += 1;
dst += 1;
count--;
}
}
}
///////////////////////////////////////////////////////////////////////////////
const SkBlitRow::Proc sk_blitrow_platform_565_procs_arm_neon[] = {
// no dither
// NOTE: For the two functions below, we don't have a special version
// that assumes that each source pixel is opaque. But our S32A is
// still faster than the default, so use it.
S32A_D565_Opaque_neon, // really S32_D565_Opaque
S32A_D565_Blend_neon, // really S32_D565_Blend
S32A_D565_Opaque_neon,
S32A_D565_Blend_neon,
// dither
S32_D565_Opaque_Dither_neon,
S32_D565_Blend_Dither_neon,
S32A_D565_Opaque_Dither_neon,
NULL, // S32A_D565_Blend_Dither
};
const SkBlitRow::Proc sk_blitrow_platform_4444_procs_arm_neon[] = {
// no dither
NULL, // S32_D4444_Opaque,
NULL, // S32_D4444_Blend,
NULL, // S32A_D4444_Opaque,
NULL, // S32A_D4444_Blend,
// dither
NULL, // S32_D4444_Opaque_Dither,
NULL, // S32_D4444_Blend_Dither,
NULL, // S32A_D4444_Opaque_Dither,
NULL, // S32A_D4444_Blend_Dither
};
const SkBlitRow::Proc32 sk_blitrow_platform_32_procs_arm_neon[] = {
NULL, // S32_Opaque,
S32_Blend_BlitRow32_neon, // S32_Blend,
S32A_Opaque_BlitRow32_neon, // S32A_Opaque,
S32A_Blend_BlitRow32_arm // S32A_Blend
};