diff options
Diffstat (limited to 'disas/libvixl/vixl/compiler-intrinsics.h')
| -rw-r--r-- | disas/libvixl/vixl/compiler-intrinsics.h | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/disas/libvixl/vixl/compiler-intrinsics.h b/disas/libvixl/vixl/compiler-intrinsics.h new file mode 100644 index 0000000000..9431beddb9 --- /dev/null +++ b/disas/libvixl/vixl/compiler-intrinsics.h @@ -0,0 +1,155 @@ +// Copyright 2015, ARM Limited +// All rights reserved. +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are met: +// +// * Redistributions of source code must retain the above copyright notice, +// this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above copyright notice, +// this list of conditions and the following disclaimer in the documentation +// and/or other materials provided with the distribution. +// * Neither the name of ARM Limited nor the names of its contributors may be +// used to endorse or promote products derived from this software without +// specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS CONTRIBUTORS "AS IS" AND +// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED +// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE +// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE +// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR +// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER +// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, +// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + + +#ifndef VIXL_COMPILER_INTRINSICS_H +#define VIXL_COMPILER_INTRINSICS_H + +#include "globals.h" + +namespace vixl { + +// Helper to check whether the version of GCC used is greater than the specified +// requirement. +#define MAJOR 1000000 +#define MINOR 1000 +#if defined(__GNUC__) && defined(__GNUC_MINOR__) && defined(__GNUC_PATCHLEVEL__) +#define GCC_VERSION_OR_NEWER(major, minor, patchlevel) \ + ((__GNUC__ * MAJOR + __GNUC_MINOR__ * MINOR + __GNUC_PATCHLEVEL__) >= \ + ((major) * MAJOR + (minor) * MINOR + (patchlevel))) +#elif defined(__GNUC__) && defined(__GNUC_MINOR__) +#define GCC_VERSION_OR_NEWER(major, minor, patchlevel) \ + ((__GNUC__ * MAJOR + __GNUC_MINOR__ * MINOR) >= \ + ((major) * MAJOR + (minor) * MINOR + (patchlevel))) +#else +#define GCC_VERSION_OR_NEWER(major, minor, patchlevel) 0 +#endif + + +#if defined(__clang__) && !defined(VIXL_NO_COMPILER_BUILTINS) + +#define COMPILER_HAS_BUILTIN_CLRSB (__has_builtin(__builtin_clrsb)) +#define COMPILER_HAS_BUILTIN_CLZ (__has_builtin(__builtin_clz)) +#define COMPILER_HAS_BUILTIN_CTZ (__has_builtin(__builtin_ctz)) +#define COMPILER_HAS_BUILTIN_FFS (__has_builtin(__builtin_ffs)) +#define COMPILER_HAS_BUILTIN_POPCOUNT (__has_builtin(__builtin_popcount)) + +#elif defined(__GNUC__) && !defined(VIXL_NO_COMPILER_BUILTINS) +// The documentation for these builtins is available at: +// https://gcc.gnu.org/onlinedocs/gcc-$MAJOR.$MINOR.$PATCHLEVEL/gcc//Other-Builtins.html + +# define COMPILER_HAS_BUILTIN_CLRSB (GCC_VERSION_OR_NEWER(4, 7, 0)) +# define COMPILER_HAS_BUILTIN_CLZ (GCC_VERSION_OR_NEWER(3, 4, 0)) +# define COMPILER_HAS_BUILTIN_CTZ (GCC_VERSION_OR_NEWER(3, 4, 0)) +# define COMPILER_HAS_BUILTIN_FFS (GCC_VERSION_OR_NEWER(3, 4, 0)) +# define COMPILER_HAS_BUILTIN_POPCOUNT (GCC_VERSION_OR_NEWER(3, 4, 0)) + +#else +// One can define VIXL_NO_COMPILER_BUILTINS to force using the manually +// implemented C++ methods. + +#define COMPILER_HAS_BUILTIN_BSWAP false +#define COMPILER_HAS_BUILTIN_CLRSB false +#define COMPILER_HAS_BUILTIN_CLZ false +#define COMPILER_HAS_BUILTIN_CTZ false +#define COMPILER_HAS_BUILTIN_FFS false +#define COMPILER_HAS_BUILTIN_POPCOUNT false + +#endif + + +template<typename V> +inline bool IsPowerOf2(V value) { + return (value != 0) && ((value & (value - 1)) == 0); +} + + +// Declaration of fallback functions. +int CountLeadingSignBitsFallBack(int64_t value, int width); +int CountLeadingZerosFallBack(uint64_t value, int width); +int CountSetBitsFallBack(uint64_t value, int width); +int CountTrailingZerosFallBack(uint64_t value, int width); + + +// Implementation of intrinsics functions. +// TODO: The implementations could be improved for sizes different from 32bit +// and 64bit: we could mask the values and call the appropriate builtin. + +template<typename V> +inline int CountLeadingSignBits(V value, int width = (sizeof(V) * 8)) { +#if COMPILER_HAS_BUILTIN_CLRSB + if (width == 32) { + return __builtin_clrsb(value); + } else if (width == 64) { + return __builtin_clrsbll(value); + } +#endif + return CountLeadingSignBitsFallBack(value, width); +} + + +template<typename V> +inline int CountLeadingZeros(V value, int width = (sizeof(V) * 8)) { +#if COMPILER_HAS_BUILTIN_CLZ + if (width == 32) { + return (value == 0) ? 32 : __builtin_clz(static_cast<unsigned>(value)); + } else if (width == 64) { + return (value == 0) ? 64 : __builtin_clzll(value); + } +#endif + return CountLeadingZerosFallBack(value, width); +} + + +template<typename V> +inline int CountSetBits(V value, int width = (sizeof(V) * 8)) { +#if COMPILER_HAS_BUILTIN_POPCOUNT + if (width == 32) { + return __builtin_popcount(static_cast<unsigned>(value)); + } else if (width == 64) { + return __builtin_popcountll(value); + } +#endif + return CountSetBitsFallBack(value, width); +} + + +template<typename V> +inline int CountTrailingZeros(V value, int width = (sizeof(V) * 8)) { +#if COMPILER_HAS_BUILTIN_CTZ + if (width == 32) { + return (value == 0) ? 32 : __builtin_ctz(static_cast<unsigned>(value)); + } else if (width == 64) { + return (value == 0) ? 64 : __builtin_ctzll(value); + } +#endif + return CountTrailingZerosFallBack(value, width); +} + +} // namespace vixl + +#endif // VIXL_COMPILER_INTRINSICS_H + |