Move CPU feature detection to its own file.

src/core/SkUtilsArm.h

 /*
  * 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.
  */
 
 #ifndef SkUtilsArm_DEFINED
 #define SkUtilsArm_DEFINED
 
+#include "SkCpu.h"
 #include "SkUtils.h"
 
 // Define SK_ARM_NEON_MODE to one of the following values
 // corresponding respectively to:
 // - No ARM Neon support at all  (not targetting ARMv7-A, or don't have NEON)
 // - Full ARM Neon support (i.e. assume the CPU always supports it)
 // - Optional ARM Neon support (i.e. probe CPU at runtime)
 //
 #define SK_ARM_NEON_MODE_NONE     0
 #define SK_ARM_NEON_MODE_ALWAYS   1
 #define SK_ARM_NEON_MODE_DYNAMIC  2
 
 #if defined(SK_ARM_HAS_OPTIONAL_NEON)
 #  define SK_ARM_NEON_MODE  SK_ARM_NEON_MODE_DYNAMIC
 #elif defined(SK_ARM_HAS_NEON)
 #  define SK_ARM_NEON_MODE  SK_ARM_NEON_MODE_ALWAYS
 #else
 #  define SK_ARM_NEON_MODE  SK_ARM_NEON_MODE_NONE
 #endif
 
 // Convenience test macros, always defined as 0 or 1
 #define SK_ARM_NEON_IS_NONE    (SK_ARM_NEON_MODE == SK_ARM_NEON_MODE_NONE)
 #define SK_ARM_NEON_IS_ALWAYS  (SK_ARM_NEON_MODE == SK_ARM_NEON_MODE_ALWAYS)
 #define SK_ARM_NEON_IS_DYNAMIC (SK_ARM_NEON_MODE == SK_ARM_NEON_MODE_DYNAMIC)
 
 // The sk_cpu_arm_has_neon() function returns true iff the target device
 // is ARMv7-A and supports Neon instructions. In DYNAMIC mode, this actually
 // probes the CPU at runtime (and caches the result).
 
+static inline bool sk_cpu_arm_has_neon(void) {
 #if SK_ARM_NEON_IS_NONE
-static inline bool sk_cpu_arm_has_neon(void) {
     return false;
+#else
+    return SkCpu::Supports(SkCpu::NEON);
+#endif
 }
-#elif SK_ARM_NEON_IS_ALWAYS
-static inline bool sk_cpu_arm_has_neon(void) {
-    return true;
-}
-#else // SK_ARM_NEON_IS_DYNAMIC
-
-extern bool sk_cpu_arm_has_neon(void) SK_PURE_FUNC;
-#endif
 
 // Use SK_ARM_NEON_WRAP(symbol) to map 'symbol' to a NEON-specific symbol
 // when applicable. This will transform 'symbol' differently depending on
 // the current NEON configuration, i.e.:
 //
 //    NONE           -> 'symbol'
 //    ALWAYS         -> 'symbol_neon'
 //    DYNAMIC        -> 'symbol' or 'symbol_neon' depending on runtime check.
 //
 // The goal is to simplify user code, for example:
@@ skipping 15 matching lines @@
 //
 #if SK_ARM_NEON_IS_NONE
 #  define SK_ARM_NEON_WRAP(x)   (x)
 #elif SK_ARM_NEON_IS_ALWAYS
 #  define SK_ARM_NEON_WRAP(x)   (x ## _neon)
 #elif SK_ARM_NEON_IS_DYNAMIC
 #  define SK_ARM_NEON_WRAP(x)   (sk_cpu_arm_has_neon() ? x ## _neon : x)
 #endif
 
 #endif // SkUtilsArm_DEFINED