1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/gfx/skia/trunk/src/core/SkUtilsArm.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,87 @@
1.4 +
1.5 +/*
1.6 + * Copyright 2012 The Android Open Source Project
1.7 + *
1.8 + * Use of this source code is governed by a BSD-style license that can be
1.9 + * found in the LICENSE file.
1.10 + */
1.11 +
1.12 +#ifndef SkUtilsArm_DEFINED
1.13 +#define SkUtilsArm_DEFINED
1.14 +
1.15 +#include "SkUtils.h"
1.16 +
1.17 +// Define SK_ARM_NEON_MODE to one of the following values
1.18 +// corresponding respectively to:
1.19 +// - No ARM Neon support at all (not targetting ARMv7-A, or don't have NEON)
1.20 +// - Full ARM Neon support (i.e. assume the CPU always supports it)
1.21 +// - Optional ARM Neon support (i.e. probe CPU at runtime)
1.22 +//
1.23 +#define SK_ARM_NEON_MODE_NONE 0
1.24 +#define SK_ARM_NEON_MODE_ALWAYS 1
1.25 +#define SK_ARM_NEON_MODE_DYNAMIC 2
1.26 +
1.27 +#if defined(SK_CPU_ARM) && defined(__ARM_HAVE_OPTIONAL_NEON_SUPPORT)
1.28 +# define SK_ARM_NEON_MODE SK_ARM_NEON_MODE_DYNAMIC
1.29 +#elif defined(SK_CPU_ARM) && defined(__ARM_HAVE_NEON)
1.30 +# define SK_ARM_NEON_MODE SK_ARM_NEON_MODE_ALWAYS
1.31 +#else
1.32 +# define SK_ARM_NEON_MODE SK_ARM_NEON_MODE_NONE
1.33 +#endif
1.34 +
1.35 +// Convenience test macros, always defined as 0 or 1
1.36 +#define SK_ARM_NEON_IS_NONE (SK_ARM_NEON_MODE == SK_ARM_NEON_MODE_NONE)
1.37 +#define SK_ARM_NEON_IS_ALWAYS (SK_ARM_NEON_MODE == SK_ARM_NEON_MODE_ALWAYS)
1.38 +#define SK_ARM_NEON_IS_DYNAMIC (SK_ARM_NEON_MODE == SK_ARM_NEON_MODE_DYNAMIC)
1.39 +
1.40 +// The sk_cpu_arm_has_neon() function returns true iff the target device
1.41 +// is ARMv7-A and supports Neon instructions. In DYNAMIC mode, this actually
1.42 +// probes the CPU at runtime (and caches the result).
1.43 +
1.44 +#if SK_ARM_NEON_IS_NONE
1.45 +static inline bool sk_cpu_arm_has_neon(void) {
1.46 + return false;
1.47 +}
1.48 +#elif SK_ARM_NEON_IS_ALWAYS
1.49 +static inline bool sk_cpu_arm_has_neon(void) {
1.50 + return true;
1.51 +}
1.52 +#else // SK_ARM_NEON_IS_DYNAMIC
1.53 +
1.54 +extern bool sk_cpu_arm_has_neon(void) SK_PURE_FUNC;
1.55 +#endif
1.56 +
1.57 +// Use SK_ARM_NEON_WRAP(symbol) to map 'symbol' to a NEON-specific symbol
1.58 +// when applicable. This will transform 'symbol' differently depending on
1.59 +// the current NEON configuration, i.e.:
1.60 +//
1.61 +// NONE -> 'symbol'
1.62 +// ALWAYS -> 'symbol_neon'
1.63 +// DYNAMIC -> 'symbol' or 'symbol_neon' depending on runtime check.
1.64 +//
1.65 +// The goal is to simplify user code, for example:
1.66 +//
1.67 +// return SK_ARM_NEON_WRAP(do_something)(params);
1.68 +//
1.69 +// Replaces the equivalent:
1.70 +//
1.71 +// #if SK_ARM_NEON_IS_NONE
1.72 +// return do_something(params);
1.73 +// #elif SK_ARM_NEON_IS_ALWAYS
1.74 +// return do_something_neon(params);
1.75 +// #elif SK_ARM_NEON_IS_DYNAMIC
1.76 +// if (sk_cpu_arm_has_neon())
1.77 +// return do_something_neon(params);
1.78 +// else
1.79 +// return do_something(params);
1.80 +// #endif
1.81 +//
1.82 +#if SK_ARM_NEON_IS_NONE
1.83 +# define SK_ARM_NEON_WRAP(x) (x)
1.84 +#elif SK_ARM_NEON_IS_ALWAYS
1.85 +# define SK_ARM_NEON_WRAP(x) (x ## _neon)
1.86 +#elif SK_ARM_NEON_IS_DYNAMIC
1.87 +# define SK_ARM_NEON_WRAP(x) (sk_cpu_arm_has_neon() ? x ## _neon : x)
1.88 +#endif
1.89 +
1.90 +#endif // SkUtilsArm_DEFINED
