Implement a NEON version of morphology. This is good for ~2.2X speedup on Tegra3.

src/opts/opts_check_arm.cpp

 /***************************************************************************
  * Copyright (c) 2010, Code Aurora Forum. All rights reserved.
  * Copyright 2006-2010, 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.
  ***************************************************************************/
 
 /* Changes:
  * 2011-04-01 ARM
  *    Merged the functions from src/opts/opts_check_arm_neon.cpp
  *    Modified to return ARM version of memset16 and memset32 if no neon
  *    available in the core
  */
 
 #include "SkBlitRow.h"
 #include "SkUtils.h"
 
 #include "SkUtilsArm.h"
+#include "SkMorphology_opts.h"
+#include "SkMorphology_opts_neon.h"
 
 #if defined(SK_CPU_LENDIAN) && !SK_ARM_NEON_IS_NONE
 extern "C" void memset16_neon(uint16_t dst[], uint16_t value, int count);
 extern "C" void memset32_neon(uint32_t dst[], uint32_t value, int count);
 #endif
 
 #if defined(SK_CPU_LENDIAN)
 extern "C" void arm_memset16(uint16_t* dst, uint16_t value, int count);
 extern "C" void arm_memset32(uint32_t* dst, uint32_t value, int count);
 #endif
@@ skipping 28 matching lines @@
 #elif SK_ARM_NEON_IS_ALWAYS
     return memset32_neon;
 #else
     return arm_memset32;
 #endif
 }
 
 SkBlitRow::ColorRectProc PlatformColorRectProcFactory() {
     return NULL;
 }
+
+SkMorphologyProc SkMorphologyGetPlatformProc(SkMorphologyProcType type) {

[mtklein, 2013/11/11 16:05:55]

I think for completeness' sake, this wants to be:
#if SK_ARM_NEON_IS_NONE
    return NULL;
#elif SK_ARM_NEON_IS_DYNAMIC
    ...
#endif

(Though maybe we should consider dropping SK_ARM_NEON_IS_NONE.  I like thinking
about your code better.)

+#if SK_ARM_NEON_IS_DYNAMIC
+    if (!sk_cpu_arm_has_neon()) {
+        return NULL;
+    }
+#endif
+    switch (type) {
+        case kDilateX_SkMorphologyProcType:
+            return SkDilateX_neon;
+        case kDilateY_SkMorphologyProcType:
+            return SkDilateY_neon;
+        case kErodeX_SkMorphologyProcType:
+            return SkErodeX_neon;
+        case kErodeY_SkMorphologyProcType:
+            return SkErodeY_neon;
+        default:
+            return NULL;
+    }
+}