Optimize RGB16 blitH functions with NEON for ARM platform.
Here are some performance resultsi on Nexus 9:
SkRGB16BlitterBlitH_neon:
+--------+-----------+
|height | C/NEON |
+--------+-----------+
|1 | 0.888531 |
+--------+-----------+
|8 | 1.231800 |
+--------+-----------+
|18 | 1.073327 |
+--------+-----------+
|32 | 1.136991 |
+--------+-----------+
|76 | 1.174638 |
+--------+-----------+
|85 | 1.188551 |
+--------+-----------+
|120 | 1.180261 |
+--------+-----------+
|128 | 1.183726 |
+--------+-----------+
|512 | 1.220806 |
+--------+-----------+
BUG=skia:
Review URL: https://codereview.chromium.org/1229673008
diff --git a/src/core/SkBlitter_RGB16.cpp b/src/core/SkBlitter_RGB16.cpp
index 8caf908..b481b27 100644
--- a/src/core/SkBlitter_RGB16.cpp
+++ b/src/core/SkBlitter_RGB16.cpp
@@ -27,6 +27,10 @@
size_t deviceRB,
unsigned scale,
uint32_t src32);
+extern void SkRGB16BlitterBlitH_neon(uint16_t* device,
+ int width,
+ unsigned scale,
+ uint32_t src32);
#else
// if we don't have neon, then our black blitter is worth the extra code
#define USE_BLACK_BLITTER
@@ -338,10 +342,14 @@
uint32_t src32 = srcExpanded * scale5;
scale5 = 32 - scale5; // now we can use it on the device
int n = count;
+#if SK_ARM_NEON_IS_ALWAYS && defined(SK_CPU_LENDIAN)
+ SkRGB16BlitterBlitH_neon(device, n, scale5, src32);
+#else
do {
uint32_t dst32 = SkExpand_rgb_16(*device) * scale5;
*device++ = SkCompact_rgb_16((src32 + dst32) >> 5);
} while (--n != 0);
+#endif
goto DONE;
}
}
@@ -601,10 +609,14 @@
unsigned scale5 = SkAlpha255To256(aa) * scale >> (8 + 3);
uint32_t src32 = srcExpanded * scale5;
scale5 = 32 - scale5;
+#if SK_ARM_NEON_IS_ALWAYS && defined(SK_CPU_LENDIAN)
+ SkRGB16BlitterBlitH_neon(device, count, scale5, src32);
+#else
do {
uint32_t dst32 = SkExpand_rgb_16(*device) * scale5;
*device++ = SkCompact_rgb_16((src32 + dst32) >> 5);
} while (--count != 0);
+#endif
continue;
}
device += count;
diff --git a/src/opts/SkBlitMask_opts_arm_neon.cpp b/src/opts/SkBlitMask_opts_arm_neon.cpp
index 3361a5d..370780c 100644
--- a/src/opts/SkBlitMask_opts_arm_neon.cpp
+++ b/src/opts/SkBlitMask_opts_arm_neon.cpp
@@ -332,3 +332,48 @@
#undef LOAD_LANE_16
#undef STORE_LANE_16
+
+void SkRGB16BlitterBlitH_neon(uint16_t* device,
+ int width,
+ unsigned scale,
+ uint32_t src32) {
+ if (width >= 8) {
+ // prepare constants
+ uint16x8_t vdev = vdupq_n_u16(0);
+ uint16x8_t vmaskq_g16 = vdupq_n_u16(SK_G16_MASK_IN_PLACE);
+ uint16x8_t vmaskq_ng16 = vdupq_n_u16(~SK_G16_MASK_IN_PLACE);
+ uint32x4_t vsrc32 = vdupq_n_u32(src32);
+ uint32x4_t vscale5 = vdupq_n_u32((uint32_t)scale);
+
+ while (width >= 8) {
+ vdev = vld1q_u16(device);
+
+ // Expand_rgb_16
+ uint16x8x2_t vdst = vzipq_u16((vdev & vmaskq_ng16), (vdev & vmaskq_g16));
+ uint32x4_t vdst32_lo = vmulq_u32(vreinterpretq_u32_u16(vdst.val[0]), vscale5);
+ uint32x4_t vdst32_hi = vmulq_u32(vreinterpretq_u32_u16(vdst.val[1]), vscale5);
+
+ // Compact_rgb_16
+ vdst32_lo = vaddq_u32(vdst32_lo, vsrc32);
+ vdst32_hi = vaddq_u32(vdst32_hi, vsrc32);
+ vdst32_lo = vshrq_n_u32(vdst32_lo, 5);
+ vdst32_hi = vshrq_n_u32(vdst32_hi, 5);
+
+ uint16x4_t vtmp_lo = vmovn_u32(vdst32_lo) & vget_low_u16(vmaskq_ng16);
+ uint16x4_t vtmp_hi = vshrn_n_u32(vdst32_lo, 16) & vget_low_u16(vmaskq_g16);
+ uint16x4_t vdst16_lo = vorr_u16(vtmp_lo, vtmp_hi);
+ vtmp_lo = vmovn_u32(vdst32_hi) & vget_low_u16(vmaskq_ng16);
+ vtmp_hi = vshrn_n_u32(vdst32_hi, 16) & vget_low_u16(vmaskq_g16);
+ uint16x4_t vdst16_hi = vorr_u16(vtmp_lo, vtmp_hi);
+
+ vst1q_u16(device, vcombine_u16(vdst16_lo, vdst16_hi));
+ device += 8;
+ width -= 8;
+ }
+ }
+ while (width != 0) {
+ uint32_t dst32 = SkExpand_rgb_16(*device) * scale;
+ *device++ = SkCompact_rgb_16((src32 + dst32) >> 5);
+ width--;
+ }
+}
