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diff --git a/src/zstd/lib/common/compiler.h b/src/zstd/lib/common/compiler.h
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+/*
+ * Copyright (c) 2016-2020, 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(ZSTD_NO_INLINE)
+#if (defined(__GNUC__) && !defined(__STRICT_ANSI__)) || defined(__cplusplus) || defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */
+# define INLINE_KEYWORD inline
+#else
+# define INLINE_KEYWORD
+#endif
+
+#if defined(__GNUC__) || defined(__ICCARM__)
+# define FORCE_INLINE_ATTR __attribute__((always_inline))
+#elif defined(_MSC_VER)
+# define FORCE_INLINE_ATTR __forceinline
+#else
+# define FORCE_INLINE_ATTR
+#endif
+
+#else
+
+#define INLINE_KEYWORD
+#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 eliminate 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
+
+/* UNUSED_ATTR tells the compiler it is okay if the function is unused. */
+#if defined(__GNUC__)
+# define UNUSED_ATTR __attribute__((unused))
+#else
+# define UNUSED_ATTR
+#endif
+
+/* force no inlining */
+#ifdef _MSC_VER
+# define FORCE_NOINLINE static __declspec(noinline)
+#else
+# if defined(__GNUC__) || defined(__ICCARM__)
+# define FORCE_NOINLINE static __attribute__((__noinline__))
+# else
+# define FORCE_NOINLINE static
+# endif
+#endif
+
+/* target attribute */
+#ifndef __has_attribute
+ #define __has_attribute(x) 0 /* Compatibility with non-clang compilers. */
+#endif
+#if defined(__GNUC__) || defined(__ICCARM__)
+# define TARGET_ATTRIBUTE(target) __attribute__((__target__(target)))
+#else
+# define TARGET_ATTRIBUTE(target)
+#endif
+
+/* Enable runtime BMI2 dispatch based on the CPU.
+ * Enabled for clang & gcc >=4.8 on x86 when BMI2 isn't enabled by default.
+ */
+#ifndef DYNAMIC_BMI2
+ #if ((defined(__clang__) && __has_attribute(__target__)) \
+ || (defined(__GNUC__) \
+ && (__GNUC__ >= 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8)))) \
+ && (defined(__x86_64__) || defined(_M_X86)) \
+ && !defined(__BMI2__)
+ # define DYNAMIC_BMI2 1
+ #else
+ # define DYNAMIC_BMI2 0
+ #endif
+#endif
+
+/* prefetch
+ * can be disabled, by declaring NO_PREFETCH build macro */
+#if defined(NO_PREFETCH)
+# define PREFETCH_L1(ptr) (void)(ptr) /* disabled */
+# define PREFETCH_L2(ptr) (void)(ptr) /* disabled */
+#else
+# 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_L1(ptr) _mm_prefetch((const char*)(ptr), _MM_HINT_T0)
+# define PREFETCH_L2(ptr) _mm_prefetch((const char*)(ptr), _MM_HINT_T1)
+# elif defined(__aarch64__)
+# define PREFETCH_L1(ptr) __asm__ __volatile__("prfm pldl1keep, %0" ::"Q"(*(ptr)))
+# define PREFETCH_L2(ptr) __asm__ __volatile__("prfm pldl2keep, %0" ::"Q"(*(ptr)))
+# elif defined(__GNUC__) && ( (__GNUC__ >= 4) || ( (__GNUC__ == 3) && (__GNUC_MINOR__ >= 1) ) )
+# define PREFETCH_L1(ptr) __builtin_prefetch((ptr), 0 /* rw==read */, 3 /* locality */)
+# define PREFETCH_L2(ptr) __builtin_prefetch((ptr), 0 /* rw==read */, 2 /* locality */)
+# else
+# define PREFETCH_L1(ptr) (void)(ptr) /* disabled */
+# define PREFETCH_L2(ptr) (void)(ptr) /* disabled */
+# endif
+#endif /* NO_PREFETCH */
+
+#define CACHELINE_SIZE 64
+
+#define PREFETCH_AREA(p, s) { \
+ const char* const _ptr = (const char*)(p); \
+ size_t const _size = (size_t)(s); \
+ size_t _pos; \
+ for (_pos=0; _pos<_size; _pos+=CACHELINE_SIZE) { \
+ PREFETCH_L2(_ptr + _pos); \
+ } \
+}
+
+/* vectorization
+ * older GCC (pre gcc-4.3 picked as the cutoff) uses a different syntax */
+#if !defined(__INTEL_COMPILER) && !defined(__clang__) && defined(__GNUC__)
+# if (__GNUC__ == 4 && __GNUC_MINOR__ > 3) || (__GNUC__ >= 5)
+# define DONT_VECTORIZE __attribute__((optimize("no-tree-vectorize")))
+# else
+# define DONT_VECTORIZE _Pragma("GCC optimize(\"no-tree-vectorize\")")
+# endif
+#else
+# define DONT_VECTORIZE
+#endif
+
+/* Tell the compiler that a branch is likely or unlikely.
+ * Only use these macros if it causes the compiler to generate better code.
+ * If you can remove a LIKELY/UNLIKELY annotation without speed changes in gcc
+ * and clang, please do.
+ */
+#if defined(__GNUC__)
+#define LIKELY(x) (__builtin_expect((x), 1))
+#define UNLIKELY(x) (__builtin_expect((x), 0))
+#else
+#define LIKELY(x) (x)
+#define UNLIKELY(x) (x)
+#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 */