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-rw-r--r--src/zstd/lib/common/compiler.h86
1 files changed, 86 insertions, 0 deletions
diff --git a/src/zstd/lib/common/compiler.h b/src/zstd/lib/common/compiler.h
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+/*
+ * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under both the BSD-style license (found in the
+ * LICENSE file in the root directory of this source tree) and the GPLv2 (found
+ * in the COPYING file in the root directory of this source tree).
+ * You may select, at your option, one of the above-listed licenses.
+ */
+
+#ifndef ZSTD_COMPILER_H
+#define ZSTD_COMPILER_H
+
+/*-*******************************************************
+* Compiler specifics
+*********************************************************/
+/* force inlining */
+#if defined (__GNUC__) || defined(__cplusplus) || defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */
+# define INLINE_KEYWORD inline
+#else
+# define INLINE_KEYWORD
+#endif
+
+#if defined(__GNUC__)
+# define FORCE_INLINE_ATTR __attribute__((always_inline))
+#elif defined(_MSC_VER)
+# define FORCE_INLINE_ATTR __forceinline
+#else
+# define FORCE_INLINE_ATTR
+#endif
+
+/**
+ * FORCE_INLINE_TEMPLATE is used to define C "templates", which take constant
+ * parameters. They must be inlined for the compiler to elimininate the constant
+ * branches.
+ */
+#define FORCE_INLINE_TEMPLATE static INLINE_KEYWORD FORCE_INLINE_ATTR
+/**
+ * HINT_INLINE is used to help the compiler generate better code. It is *not*
+ * used for "templates", so it can be tweaked based on the compilers
+ * performance.
+ *
+ * gcc-4.8 and gcc-4.9 have been shown to benefit from leaving off the
+ * always_inline attribute.
+ *
+ * clang up to 5.0.0 (trunk) benefit tremendously from the always_inline
+ * attribute.
+ */
+#if !defined(__clang__) && defined(__GNUC__) && __GNUC__ >= 4 && __GNUC_MINOR__ >= 8 && __GNUC__ < 5
+# define HINT_INLINE static INLINE_KEYWORD
+#else
+# define HINT_INLINE static INLINE_KEYWORD FORCE_INLINE_ATTR
+#endif
+
+/* force no inlining */
+#ifdef _MSC_VER
+# define FORCE_NOINLINE static __declspec(noinline)
+#else
+# ifdef __GNUC__
+# define FORCE_NOINLINE static __attribute__((__noinline__))
+# else
+# define FORCE_NOINLINE static
+# endif
+#endif
+
+/* prefetch */
+#if defined(_MSC_VER) && (defined(_M_X64) || defined(_M_I86)) /* _mm_prefetch() is not defined outside of x86/x64 */
+# include <mmintrin.h> /* https://msdn.microsoft.com/fr-fr/library/84szxsww(v=vs.90).aspx */
+# define PREFETCH(ptr) _mm_prefetch((const char*)ptr, _MM_HINT_T0)
+#elif defined(__GNUC__)
+# define PREFETCH(ptr) __builtin_prefetch(ptr, 0, 0)
+#else
+# define PREFETCH(ptr) /* disabled */
+#endif
+
+/* disable warnings */
+#ifdef _MSC_VER /* Visual Studio */
+# include <intrin.h> /* For Visual 2005 */
+# pragma warning(disable : 4100) /* disable: C4100: unreferenced formal parameter */
+# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */
+# pragma warning(disable : 4204) /* disable: C4204: non-constant aggregate initializer */
+# pragma warning(disable : 4214) /* disable: C4214: non-int bitfields */
+# pragma warning(disable : 4324) /* disable: C4324: padded structure */
+#endif
+
+#endif /* ZSTD_COMPILER_H */