[pcsx_rearmed.git] / deps / libchdr / deps / zstd-1.5.6 / lib / common / compiler.h

/*
 * Copyright (c) Meta Platforms, Inc. and affiliates.
 * 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

#include <stddef.h>

#include "portability_macros.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

/**
  On MSVC qsort requires that functions passed into it use the __cdecl calling conversion(CC).
  This explicitly marks such functions as __cdecl so that the code will still compile
  if a CC other than __cdecl has been made the default.
*/
#if  defined(_MSC_VER)
#  define WIN_CDECL __cdecl
#else
#  define WIN_CDECL
#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_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 UNUSED_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 FORCE_INLINE_TEMPLATE
#endif

/* "soft" inline :
 * The compiler is free to select if it's a good idea to inline or not.
 * The main objective is to silence compiler warnings
 * when a defined function in included but not used.
 *
 * Note : this macro is prefixed `MEM_` because it used to be provided by `mem.h` unit.
 * Updating the prefix is probably preferable, but requires a fairly large codemod,
 * since this name is used everywhere.
 */
#ifndef MEM_STATIC  /* already defined in Linux Kernel mem.h */
#if defined(__GNUC__)
#  define MEM_STATIC static __inline UNUSED_ATTR
#elif defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
#  define MEM_STATIC static inline
#elif defined(_MSC_VER)
#  define MEM_STATIC static __inline
#else
#  define MEM_STATIC static  /* this version may generate warnings for unused static functions; disable the relevant warning */
#endif
#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 */
#if defined(__GNUC__) || defined(__ICCARM__)
#  define TARGET_ATTRIBUTE(target) __attribute__((__target__(target)))
#else
#  define TARGET_ATTRIBUTE(target)
#endif

/* Target attribute for BMI2 dynamic dispatch.
 * Enable lzcnt, bmi, and bmi2.
 * We test for bmi1 & bmi2. lzcnt is included in bmi1.
 */
#define BMI2_TARGET_ATTRIBUTE TARGET_ATTRIBUTE("lzcnt,bmi,bmi2")

/* prefetch
 * can be disabled, by declaring NO_PREFETCH build macro */
#if defined(NO_PREFETCH)
#  define PREFETCH_L1(ptr)  do { (void)(ptr); } while (0)  /* disabled */
#  define PREFETCH_L2(ptr)  do { (void)(ptr); } while (0)  /* disabled */
#else
#  if defined(_MSC_VER) && (defined(_M_X64) || defined(_M_I86)) && !defined(_M_ARM64EC)  /* _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(__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 */)
#  elif defined(__aarch64__)
#    define PREFETCH_L1(ptr)  do { __asm__ __volatile__("prfm pldl1keep, %0" ::"Q"(*(ptr))); } while (0)
#    define PREFETCH_L2(ptr)  do { __asm__ __volatile__("prfm pldl2keep, %0" ::"Q"(*(ptr))); } while (0)
#  else
#    define PREFETCH_L1(ptr) do { (void)(ptr); } while (0)  /* disabled */
#    define PREFETCH_L2(ptr) do { (void)(ptr); } while (0)  /* disabled */
#  endif
#endif  /* NO_PREFETCH */

#define CACHELINE_SIZE 64

#define PREFETCH_AREA(p, s)                              \
    do {                                                 \
        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);                    \
        }                                                \
    } while (0)

/* vectorization
 * older GCC (pre gcc-4.3 picked as the cutoff) uses a different syntax,
 * and some compilers, like Intel ICC and MCST LCC, do not support it at all. */
#if !defined(__INTEL_COMPILER) && !defined(__clang__) && defined(__GNUC__) && !defined(__LCC__)
#  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

#if __has_builtin(__builtin_unreachable) || (defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)))
#  define ZSTD_UNREACHABLE do { assert(0), __builtin_unreachable(); } while (0)
#else
#  define ZSTD_UNREACHABLE do { assert(0); } while (0)
#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

/*Like DYNAMIC_BMI2 but for compile time determination of BMI2 support*/
#ifndef STATIC_BMI2
#  if defined(_MSC_VER) && (defined(_M_X64) || defined(_M_I86))
#    ifdef __AVX2__  //MSVC does not have a BMI2 specific flag, but every CPU that supports AVX2 also supports BMI2
#       define STATIC_BMI2 1
#    endif
#  elif defined(__BMI2__) && defined(__x86_64__) && defined(__GNUC__)
#    define STATIC_BMI2 1
#  endif
#endif

#ifndef STATIC_BMI2
    #define STATIC_BMI2 0
#endif

/* compile time determination of SIMD support */
#if !defined(ZSTD_NO_INTRINSICS)
#  if defined(__SSE2__) || defined(_M_AMD64) || (defined (_M_IX86) && defined(_M_IX86_FP) && (_M_IX86_FP >= 2))
#    define ZSTD_ARCH_X86_SSE2
#  endif
#  if defined(__ARM_NEON) || defined(_M_ARM64)
#    define ZSTD_ARCH_ARM_NEON
#  endif
#
#  if defined(ZSTD_ARCH_X86_SSE2)
#    include <emmintrin.h>
#  elif defined(ZSTD_ARCH_ARM_NEON)
#    include <arm_neon.h>
#  endif
#endif

/* C-language Attributes are added in C23. */
#if defined(__STDC_VERSION__) && (__STDC_VERSION__ > 201710L) && defined(__has_c_attribute)
# define ZSTD_HAS_C_ATTRIBUTE(x) __has_c_attribute(x)
#else
# define ZSTD_HAS_C_ATTRIBUTE(x) 0
#endif

/* Only use C++ attributes in C++. Some compilers report support for C++
 * attributes when compiling with C.
 */
#if defined(__cplusplus) && defined(__has_cpp_attribute)
# define ZSTD_HAS_CPP_ATTRIBUTE(x) __has_cpp_attribute(x)
#else
# define ZSTD_HAS_CPP_ATTRIBUTE(x) 0
#endif

/* Define ZSTD_FALLTHROUGH macro for annotating switch case with the 'fallthrough' attribute.
 * - C23: https://en.cppreference.com/w/c/language/attributes/fallthrough
 * - CPP17: https://en.cppreference.com/w/cpp/language/attributes/fallthrough
 * - Else: __attribute__((__fallthrough__))
 */
#ifndef ZSTD_FALLTHROUGH
# if ZSTD_HAS_C_ATTRIBUTE(fallthrough)
#  define ZSTD_FALLTHROUGH [[fallthrough]]
# elif ZSTD_HAS_CPP_ATTRIBUTE(fallthrough)
#  define ZSTD_FALLTHROUGH [[fallthrough]]
# elif __has_attribute(__fallthrough__)
/* Leading semicolon is to satisfy gcc-11 with -pedantic. Without the semicolon
 * gcc complains about: a label can only be part of a statement and a declaration is not a statement.
 */
#  define ZSTD_FALLTHROUGH ; __attribute__((__fallthrough__))
# else
#  define ZSTD_FALLTHROUGH
# endif
#endif

/*-**************************************************************
*  Alignment check
*****************************************************************/

/* this test was initially positioned in mem.h,
 * but this file is removed (or replaced) for linux kernel
 * so it's now hosted in compiler.h,
 * which remains valid for both user & kernel spaces.
 */

#ifndef ZSTD_ALIGNOF
# if defined(__GNUC__) || defined(_MSC_VER)
/* covers gcc, clang & MSVC */
/* note : this section must come first, before C11,
 * due to a limitation in the kernel source generator */
#  define ZSTD_ALIGNOF(T) __alignof(T)

# elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 201112L)
/* C11 support */
#  include <stdalign.h>
#  define ZSTD_ALIGNOF(T) alignof(T)

# else
/* No known support for alignof() - imperfect backup */
#  define ZSTD_ALIGNOF(T) (sizeof(void*) < sizeof(T) ? sizeof(void*) : sizeof(T))

# endif
#endif /* ZSTD_ALIGNOF */

/*-**************************************************************
*  Sanitizer
*****************************************************************/

/**
 * Zstd relies on pointer overflow in its decompressor.
 * We add this attribute to functions that rely on pointer overflow.
 */
#ifndef ZSTD_ALLOW_POINTER_OVERFLOW_ATTR
#  if __has_attribute(no_sanitize)
#    if !defined(__clang__) && defined(__GNUC__) && __GNUC__ < 8
       /* gcc < 8 only has signed-integer-overlow which triggers on pointer overflow */
#      define ZSTD_ALLOW_POINTER_OVERFLOW_ATTR __attribute__((no_sanitize("signed-integer-overflow")))
#    else
       /* older versions of clang [3.7, 5.0) will warn that pointer-overflow is ignored. */
#      define ZSTD_ALLOW_POINTER_OVERFLOW_ATTR __attribute__((no_sanitize("pointer-overflow")))
#    endif
#  else
#    define ZSTD_ALLOW_POINTER_OVERFLOW_ATTR
#  endif
#endif

/**
 * Helper function to perform a wrapped pointer difference without trigging
 * UBSAN.
 *
 * @returns lhs - rhs with wrapping
 */
MEM_STATIC
ZSTD_ALLOW_POINTER_OVERFLOW_ATTR
ptrdiff_t ZSTD_wrappedPtrDiff(unsigned char const* lhs, unsigned char const* rhs)
{
    return lhs - rhs;
}

/**
 * Helper function to perform a wrapped pointer add without triggering UBSAN.
 *
 * @return ptr + add with wrapping
 */
MEM_STATIC
ZSTD_ALLOW_POINTER_OVERFLOW_ATTR
unsigned char const* ZSTD_wrappedPtrAdd(unsigned char const* ptr, ptrdiff_t add)
{
    return ptr + add;
}

/**
 * Helper function to perform a wrapped pointer subtraction without triggering
 * UBSAN.
 *
 * @return ptr - sub with wrapping
 */
MEM_STATIC
ZSTD_ALLOW_POINTER_OVERFLOW_ATTR
unsigned char const* ZSTD_wrappedPtrSub(unsigned char const* ptr, ptrdiff_t sub)
{
    return ptr - sub;
}

/**
 * Helper function to add to a pointer that works around C's undefined behavior
 * of adding 0 to NULL.
 *
 * @returns `ptr + add` except it defines `NULL + 0 == NULL`.
 */
MEM_STATIC
unsigned char* ZSTD_maybeNullPtrAdd(unsigned char* ptr, ptrdiff_t add)
{
    return add > 0 ? ptr + add : ptr;
}

/* Issue #3240 reports an ASAN failure on an llvm-mingw build. Out of an
 * abundance of caution, disable our custom poisoning on mingw. */
#ifdef __MINGW32__
#ifndef ZSTD_ASAN_DONT_POISON_WORKSPACE
#define ZSTD_ASAN_DONT_POISON_WORKSPACE 1
#endif
#ifndef ZSTD_MSAN_DONT_POISON_WORKSPACE
#define ZSTD_MSAN_DONT_POISON_WORKSPACE 1
#endif
#endif

#if ZSTD_MEMORY_SANITIZER && !defined(ZSTD_MSAN_DONT_POISON_WORKSPACE)
/* Not all platforms that support msan provide sanitizers/msan_interface.h.
 * We therefore declare the functions we need ourselves, rather than trying to
 * include the header file... */
#include <stddef.h>  /* size_t */
#define ZSTD_DEPS_NEED_STDINT
#include "zstd_deps.h"  /* intptr_t */

/* Make memory region fully initialized (without changing its contents). */
void __msan_unpoison(const volatile void *a, size_t size);

/* Make memory region fully uninitialized (without changing its contents).
   This is a legacy interface that does not update origin information. Use
   __msan_allocated_memory() instead. */
void __msan_poison(const volatile void *a, size_t size);

/* Returns the offset of the first (at least partially) poisoned byte in the
   memory range, or -1 if the whole range is good. */
intptr_t __msan_test_shadow(const volatile void *x, size_t size);

/* Print shadow and origin for the memory range to stderr in a human-readable
   format. */
void __msan_print_shadow(const volatile void *x, size_t size);
#endif

#if ZSTD_ADDRESS_SANITIZER && !defined(ZSTD_ASAN_DONT_POISON_WORKSPACE)
/* Not all platforms that support asan provide sanitizers/asan_interface.h.
 * We therefore declare the functions we need ourselves, rather than trying to
 * include the header file... */
#include <stddef.h>  /* size_t */

/**
 * Marks a memory region (<c>[addr, addr+size)</c>) as unaddressable.
 *
 * This memory must be previously allocated by your program. Instrumented
 * code is forbidden from accessing addresses in this region until it is
 * unpoisoned. This function is not guaranteed to poison the entire region -
 * it could poison only a subregion of <c>[addr, addr+size)</c> due to ASan
 * alignment restrictions.
 *
 * \note This function is not thread-safe because no two threads can poison or
 * unpoison memory in the same memory region simultaneously.
 *
 * \param addr Start of memory region.
 * \param size Size of memory region. */
void __asan_poison_memory_region(void const volatile *addr, size_t size);

/**
 * Marks a memory region (<c>[addr, addr+size)</c>) as addressable.
 *
 * This memory must be previously allocated by your program. Accessing
 * addresses in this region is allowed until this region is poisoned again.
 * This function could unpoison a super-region of <c>[addr, addr+size)</c> due
 * to ASan alignment restrictions.
 *
 * \note This function is not thread-safe because no two threads can
 * poison or unpoison memory in the same memory region simultaneously.
 *
 * \param addr Start of memory region.
 * \param size Size of memory region. */
void __asan_unpoison_memory_region(void const volatile *addr, size_t size);
#endif

#endif /* ZSTD_COMPILER_H */
Commit	Line	Data
648db22b	1	/*
	2	* Copyright (c) Meta Platforms, Inc. and affiliates.
	3	* All rights reserved.
	4	*
	5	* This source code is licensed under both the BSD-style license (found in the
	6	* LICENSE file in the root directory of this source tree) and the GPLv2 (found
	7	* in the COPYING file in the root directory of this source tree).
	8	* You may select, at your option, one of the above-listed licenses.
	9	*/
	10
	11	#ifndef ZSTD_COMPILER_H
	12	#define ZSTD_COMPILER_H
	13
f535537f	14	#include <stddef.h>
f535537f	15
648db22b	16	#include "portability_macros.h"
	17
	18	/-******************************************************
	19	* Compiler specifics
	20	*********************************************************/
	21	/* force inlining */
	22
	23	#if !defined(ZSTD_NO_INLINE)
	24	#if (defined(__GNUC__) && !defined(__STRICT_ANSI__)) \|\| defined(__cplusplus) \|\| defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */
	25	# define INLINE_KEYWORD inline
	26	#else
	27	# define INLINE_KEYWORD
	28	#endif
	29
	30	#if defined(__GNUC__) \|\| defined(__ICCARM__)
	31	# define FORCE_INLINE_ATTR __attribute__((always_inline))
	32	#elif defined(_MSC_VER)
	33	# define FORCE_INLINE_ATTR __forceinline
	34	#else
	35	# define FORCE_INLINE_ATTR
	36	#endif
	37
	38	#else
	39
	40	#define INLINE_KEYWORD
	41	#define FORCE_INLINE_ATTR
	42
	43	#endif
	44
	45	/**
	46	On MSVC qsort requires that functions passed into it use the __cdecl calling conversion(CC).
	47	This explicitly marks such functions as __cdecl so that the code will still compile
	48	if a CC other than __cdecl has been made the default.
	49	*/
	50	#if defined(_MSC_VER)
	51	# define WIN_CDECL __cdecl
	52	#else
	53	# define WIN_CDECL
	54	#endif
	55
f535537f	56	/* UNUSED_ATTR tells the compiler it is okay if the function is unused. */
	57	#if defined(__GNUC__)
	58	# define UNUSED_ATTR __attribute__((unused))
	59	#else
	60	# define UNUSED_ATTR
	61	#endif
	62
648db22b	63	/**
	64	* FORCE_INLINE_TEMPLATE is used to define C "templates", which take constant
	65	* parameters. They must be inlined for the compiler to eliminate the constant
	66	* branches.
	67	*/
f535537f	68	#define FORCE_INLINE_TEMPLATE static INLINE_KEYWORD FORCE_INLINE_ATTR UNUSED_ATTR
648db22b	69	/**
	70	* HINT_INLINE is used to help the compiler generate better code. It is not
	71	* used for "templates", so it can be tweaked based on the compilers
	72	* performance.
	73	*
	74	* gcc-4.8 and gcc-4.9 have been shown to benefit from leaving off the
	75	* always_inline attribute.
	76	*
	77	* clang up to 5.0.0 (trunk) benefit tremendously from the always_inline
	78	* attribute.
	79	*/
	80	#if !defined(__clang__) && defined(__GNUC__) && __GNUC__ >= 4 && __GNUC_MINOR__ >= 8 && __GNUC__ < 5
	81	# define HINT_INLINE static INLINE_KEYWORD
	82	#else
f535537f	83	# define HINT_INLINE FORCE_INLINE_TEMPLATE
648db22b	84	#endif
648db22b	85
f535537f	86	/* "soft" inline :
	87	* The compiler is free to select if it's a good idea to inline or not.
	88	* The main objective is to silence compiler warnings
	89	* when a defined function in included but not used.
	90	*
	91	* Note : this macro is prefixed `MEM_` because it used to be provided by `mem.h` unit.
	92	* Updating the prefix is probably preferable, but requires a fairly large codemod,
	93	* since this name is used everywhere.
	94	*/
	95	#ifndef MEM_STATIC /* already defined in Linux Kernel mem.h */
648db22b	96	#if defined(__GNUC__)
f535537f	97	# define MEM_STATIC static __inline UNUSED_ATTR
	98	#elif defined (__cplusplus) \|\| (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
	99	# define MEM_STATIC static inline
	100	#elif defined(_MSC_VER)
	101	# define MEM_STATIC static __inline
648db22b	102	#else
f535537f	103	# define MEM_STATIC static /* this version may generate warnings for unused static functions; disable the relevant warning */
f535537f	104	#endif
648db22b	105	#endif
	106
	107	/* force no inlining */
	108	#ifdef _MSC_VER
	109	# define FORCE_NOINLINE static __declspec(noinline)
	110	#else
	111	# if defined(__GNUC__) \|\| defined(__ICCARM__)
	112	# define FORCE_NOINLINE static __attribute__((__noinline__))
	113	# else
	114	# define FORCE_NOINLINE static
	115	# endif
	116	#endif
	117
	118
	119	/* target attribute */
	120	#if defined(__GNUC__) \|\| defined(__ICCARM__)
	121	# define TARGET_ATTRIBUTE(target) __attribute__((__target__(target)))
	122	#else
	123	# define TARGET_ATTRIBUTE(target)
	124	#endif
	125
	126	/* Target attribute for BMI2 dynamic dispatch.
	127	* Enable lzcnt, bmi, and bmi2.
	128	* We test for bmi1 & bmi2. lzcnt is included in bmi1.
	129	*/
	130	#define BMI2_TARGET_ATTRIBUTE TARGET_ATTRIBUTE("lzcnt,bmi,bmi2")
	131
	132	/* prefetch
	133	* can be disabled, by declaring NO_PREFETCH build macro */
	134	#if defined(NO_PREFETCH)
f535537f	135	# define PREFETCH_L1(ptr) do { (void)(ptr); } while (0) /* disabled */
f535537f	136	# define PREFETCH_L2(ptr) do { (void)(ptr); } while (0) /* disabled */
648db22b	137	#else
f535537f	138	# if defined(_MSC_VER) && (defined(_M_X64) \|\| defined(_M_I86)) && !defined(_M_ARM64EC) /* _mm_prefetch() is not defined outside of x86/x64 */
648db22b	139	# include <mmintrin.h> /* https://msdn.microsoft.com/fr-fr/library/84szxsww(v=vs.90).aspx */
	140	# define PREFETCH_L1(ptr) _mm_prefetch((const char*)(ptr), _MM_HINT_T0)
	141	# define PREFETCH_L2(ptr) _mm_prefetch((const char*)(ptr), _MM_HINT_T1)
	142	# elif defined(__GNUC__) && ( (__GNUC__ >= 4) \|\| ( (__GNUC__ == 3) && (__GNUC_MINOR__ >= 1) ) )
	143	# define PREFETCH_L1(ptr) __builtin_prefetch((ptr), 0 /* rw==read /, 3 / locality */)
	144	# define PREFETCH_L2(ptr) __builtin_prefetch((ptr), 0 /* rw==read /, 2 / locality */)
	145	# elif defined(__aarch64__)
f535537f	146	# define PREFETCH_L1(ptr) do { __asm__ __volatile__("prfm pldl1keep, %0" ::"Q"(*(ptr))); } while (0)
f535537f	147	# define PREFETCH_L2(ptr) do { __asm__ __volatile__("prfm pldl2keep, %0" ::"Q"(*(ptr))); } while (0)
648db22b	148	# else
f535537f	149	# define PREFETCH_L1(ptr) do { (void)(ptr); } while (0) /* disabled */
f535537f	150	# define PREFETCH_L2(ptr) do { (void)(ptr); } while (0) /* disabled */
648db22b	151	# endif
	152	#endif /* NO_PREFETCH */
	153
	154	#define CACHELINE_SIZE 64
	155
f535537f	156	#define PREFETCH_AREA(p, s) \
	157	do { \
	158	const char* const _ptr = (const char*)(p); \
	159	size_t const _size = (size_t)(s); \
	160	size_t _pos; \
	161	for (_pos=0; _pos<_size; _pos+=CACHELINE_SIZE) { \
	162	PREFETCH_L2(_ptr + _pos); \
	163	} \
	164	} while (0)
648db22b	165
	166	/* vectorization
	167	* older GCC (pre gcc-4.3 picked as the cutoff) uses a different syntax,
	168	* and some compilers, like Intel ICC and MCST LCC, do not support it at all. */
	169	#if !defined(__INTEL_COMPILER) && !defined(__clang__) && defined(__GNUC__) && !defined(__LCC__)
	170	# if (__GNUC__ == 4 && __GNUC_MINOR__ > 3) \|\| (__GNUC__ >= 5)
	171	# define DONT_VECTORIZE __attribute__((optimize("no-tree-vectorize")))
	172	# else
	173	# define DONT_VECTORIZE _Pragma("GCC optimize(\"no-tree-vectorize\")")
	174	# endif
	175	#else
	176	# define DONT_VECTORIZE
	177	#endif
	178
	179	/* Tell the compiler that a branch is likely or unlikely.
	180	* Only use these macros if it causes the compiler to generate better code.
	181	* If you can remove a LIKELY/UNLIKELY annotation without speed changes in gcc
	182	* and clang, please do.
	183	*/
	184	#if defined(__GNUC__)
	185	#define LIKELY(x) (__builtin_expect((x), 1))
	186	#define UNLIKELY(x) (__builtin_expect((x), 0))
	187	#else
	188	#define LIKELY(x) (x)
	189	#define UNLIKELY(x) (x)
	190	#endif
	191
	192	#if __has_builtin(__builtin_unreachable) \|\| (defined(__GNUC__) && (__GNUC__ > 4 \|\| (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)))
f535537f	193	# define ZSTD_UNREACHABLE do { assert(0), __builtin_unreachable(); } while (0)
648db22b	194	#else
f535537f	195	# define ZSTD_UNREACHABLE do { assert(0); } while (0)
648db22b	196	#endif
	197
	198	/* disable warnings */
	199	#ifdef _MSC_VER /* Visual Studio */
	200	# include <intrin.h> /* For Visual 2005 */
	201	# pragma warning(disable : 4100) /* disable: C4100: unreferenced formal parameter */
	202	# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */
	203	# pragma warning(disable : 4204) /* disable: C4204: non-constant aggregate initializer */
	204	# pragma warning(disable : 4214) /* disable: C4214: non-int bitfields */
	205	# pragma warning(disable : 4324) /* disable: C4324: padded structure */
	206	#endif
	207
	208	/Like DYNAMIC_BMI2 but for compile time determination of BMI2 support/
	209	#ifndef STATIC_BMI2
	210	# if defined(_MSC_VER) && (defined(_M_X64) \|\| defined(_M_I86))
	211	# ifdef __AVX2__ //MSVC does not have a BMI2 specific flag, but every CPU that supports AVX2 also supports BMI2
	212	# define STATIC_BMI2 1
	213	# endif
	214	# elif defined(__BMI2__) && defined(__x86_64__) && defined(__GNUC__)
	215	# define STATIC_BMI2 1
	216	# endif
	217	#endif
	218
	219	#ifndef STATIC_BMI2
	220	#define STATIC_BMI2 0
	221	#endif
	222
	223	/* compile time determination of SIMD support */
	224	#if !defined(ZSTD_NO_INTRINSICS)
	225	# if defined(__SSE2__) \|\| defined(_M_AMD64) \|\| (defined (_M_IX86) && defined(_M_IX86_FP) && (_M_IX86_FP >= 2))
	226	# define ZSTD_ARCH_X86_SSE2
	227	# endif
	228	# if defined(__ARM_NEON) \|\| defined(_M_ARM64)
	229	# define ZSTD_ARCH_ARM_NEON
	230	# endif
	231	#
	232	# if defined(ZSTD_ARCH_X86_SSE2)
	233	# include <emmintrin.h>
	234	# elif defined(ZSTD_ARCH_ARM_NEON)
	235	# include <arm_neon.h>
	236	# endif
	237	#endif
	238
	239	/* C-language Attributes are added in C23. */
	240	#if defined(__STDC_VERSION__) && (__STDC_VERSION__ > 201710L) && defined(__has_c_attribute)
	241	# define ZSTD_HAS_C_ATTRIBUTE(x) __has_c_attribute(x)
	242	#else
	243	# define ZSTD_HAS_C_ATTRIBUTE(x) 0
	244	#endif
	245
	246	/* Only use C++ attributes in C++. Some compilers report support for C++
	247	* attributes when compiling with C.
	248	*/
	249	#if defined(__cplusplus) && defined(__has_cpp_attribute)
	250	# define ZSTD_HAS_CPP_ATTRIBUTE(x) __has_cpp_attribute(x)
	251	#else
	252	# define ZSTD_HAS_CPP_ATTRIBUTE(x) 0
	253	#endif
	254
	255	/* Define ZSTD_FALLTHROUGH macro for annotating switch case with the 'fallthrough' attribute.
	256	* - C23: https://en.cppreference.com/w/c/language/attributes/fallthrough
	257	* - CPP17: https://en.cppreference.com/w/cpp/language/attributes/fallthrough
	258	* - Else: __attribute__((__fallthrough__))
	259	*/
260	#ifndef ZSTD_FALLTHROUGH
261	# if ZSTD_HAS_C_ATTRIBUTE(fallthrough)
262	# define ZSTD_FALLTHROUGH [[fallthrough]]
263	# elif ZSTD_HAS_CPP_ATTRIBUTE(fallthrough)
264	# define ZSTD_FALLTHROUGH [[fallthrough]]
265	# elif __has_attribute(__fallthrough__)
266	/* Leading semicolon is to satisfy gcc-11 with -pedantic. Without the semicolon
267	* gcc complains about: a label can only be part of a statement and a declaration is not a statement.
268	*/
269	# define ZSTD_FALLTHROUGH ; __attribute__((__fallthrough__))
270	# else
271	# define ZSTD_FALLTHROUGH
272	# endif
273	#endif
274
275	/-*************************************************************
276	* Alignment check
277	*****************************************************************/
278
279	/* this test was initially positioned in mem.h,
280	* but this file is removed (or replaced) for linux kernel
281	* so it's now hosted in compiler.h,
282	* which remains valid for both user & kernel spaces.
283	*/
284
285	#ifndef ZSTD_ALIGNOF
286	# if defined(__GNUC__) \|\| defined(_MSC_VER)
287	/* covers gcc, clang & MSVC */
288	/* note : this section must come first, before C11,
289	* due to a limitation in the kernel source generator */
290	# define ZSTD_ALIGNOF(T) __alignof(T)
291
292	# elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 201112L)
293	/* C11 support */
294	# include <stdalign.h>
295	# define ZSTD_ALIGNOF(T) alignof(T)
296
297	# else
298	/* No known support for alignof() - imperfect backup */
299	# define ZSTD_ALIGNOF(T) (sizeof(void) < sizeof(T) ? sizeof(void) : sizeof(T))
300
301	# endif
302	#endif /* ZSTD_ALIGNOF */
303
304	/-*************************************************************
305	* Sanitizer
306	*****************************************************************/
307
f535537f	308	/**
	309	* Zstd relies on pointer overflow in its decompressor.
	310	* We add this attribute to functions that rely on pointer overflow.
	311	*/
	312	#ifndef ZSTD_ALLOW_POINTER_OVERFLOW_ATTR
	313	# if __has_attribute(no_sanitize)
	314	# if !defined(__clang__) && defined(__GNUC__) && __GNUC__ < 8
	315	/* gcc < 8 only has signed-integer-overlow which triggers on pointer overflow */
	316	# define ZSTD_ALLOW_POINTER_OVERFLOW_ATTR __attribute__((no_sanitize("signed-integer-overflow")))
	317	# else
	318	/* older versions of clang [3.7, 5.0) will warn that pointer-overflow is ignored. */
	319	# define ZSTD_ALLOW_POINTER_OVERFLOW_ATTR __attribute__((no_sanitize("pointer-overflow")))
	320	# endif
	321	# else
	322	# define ZSTD_ALLOW_POINTER_OVERFLOW_ATTR
	323	# endif
	324	#endif
	325
	326	/**
	327	* Helper function to perform a wrapped pointer difference without trigging
	328	* UBSAN.
	329	*
	330	* @returns lhs - rhs with wrapping
	331	*/
	332	MEM_STATIC
	333	ZSTD_ALLOW_POINTER_OVERFLOW_ATTR
	334	ptrdiff_t ZSTD_wrappedPtrDiff(unsigned char const* lhs, unsigned char const* rhs)
	335	{
	336	return lhs - rhs;
	337	}
	338
	339	/**
	340	* Helper function to perform a wrapped pointer add without triggering UBSAN.
	341	*
	342	* @return ptr + add with wrapping
	343	*/
	344	MEM_STATIC
	345	ZSTD_ALLOW_POINTER_OVERFLOW_ATTR
	346	unsigned char const* ZSTD_wrappedPtrAdd(unsigned char const* ptr, ptrdiff_t add)
	347	{
	348	return ptr + add;
	349	}
	350
	351	/**
	352	* Helper function to perform a wrapped pointer subtraction without triggering
	353	* UBSAN.
	354	*
	355	* @return ptr - sub with wrapping
	356	*/
	357	MEM_STATIC
	358	ZSTD_ALLOW_POINTER_OVERFLOW_ATTR
	359	unsigned char const* ZSTD_wrappedPtrSub(unsigned char const* ptr, ptrdiff_t sub)
	360	{
	361	return ptr - sub;
	362	}
	363
	364	/**
	365	* Helper function to add to a pointer that works around C's undefined behavior
	366	* of adding 0 to NULL.
	367	*
	368	* @returns `ptr + add` except it defines `NULL + 0 == NULL`.
	369	*/
	370	MEM_STATIC
	371	unsigned char* ZSTD_maybeNullPtrAdd(unsigned char* ptr, ptrdiff_t add)
372	{
373	return add > 0 ? ptr + add : ptr;
374	}
375
648db22b	376	/* Issue #3240 reports an ASAN failure on an llvm-mingw build. Out of an
	377	* abundance of caution, disable our custom poisoning on mingw. */
	378	#ifdef __MINGW32__
	379	#ifndef ZSTD_ASAN_DONT_POISON_WORKSPACE
	380	#define ZSTD_ASAN_DONT_POISON_WORKSPACE 1
	381	#endif
	382	#ifndef ZSTD_MSAN_DONT_POISON_WORKSPACE
	383	#define ZSTD_MSAN_DONT_POISON_WORKSPACE 1
	384	#endif
	385	#endif
	386
	387	#if ZSTD_MEMORY_SANITIZER && !defined(ZSTD_MSAN_DONT_POISON_WORKSPACE)
	388	/* Not all platforms that support msan provide sanitizers/msan_interface.h.
	389	* We therefore declare the functions we need ourselves, rather than trying to
	390	* include the header file... */
	391	#include <stddef.h> /* size_t */
	392	#define ZSTD_DEPS_NEED_STDINT
	393	#include "zstd_deps.h" /* intptr_t */
	394
	395	/* Make memory region fully initialized (without changing its contents). */
	396	void __msan_unpoison(const volatile void *a, size_t size);
	397
	398	/* Make memory region fully uninitialized (without changing its contents).
	399	This is a legacy interface that does not update origin information. Use
	400	__msan_allocated_memory() instead. */
	401	void __msan_poison(const volatile void *a, size_t size);
	402
	403	/* Returns the offset of the first (at least partially) poisoned byte in the
	404	memory range, or -1 if the whole range is good. */
	405	intptr_t __msan_test_shadow(const volatile void *x, size_t size);
	406
	407	/* Print shadow and origin for the memory range to stderr in a human-readable
	408	format. */
	409	void __msan_print_shadow(const volatile void *x, size_t size);
	410	#endif
	411
	412	#if ZSTD_ADDRESS_SANITIZER && !defined(ZSTD_ASAN_DONT_POISON_WORKSPACE)
	413	/* Not all platforms that support asan provide sanitizers/asan_interface.h.
	414	* We therefore declare the functions we need ourselves, rather than trying to
	415	* include the header file... */
	416	#include <stddef.h> /* size_t */
	417
	418	/**
	419	* Marks a memory region (<c>[addr, addr+size)</c>) as unaddressable.
	420	*
	421	* This memory must be previously allocated by your program. Instrumented
	422	* code is forbidden from accessing addresses in this region until it is
	423	* unpoisoned. This function is not guaranteed to poison the entire region -
	424	* it could poison only a subregion of <c>[addr, addr+size)</c> due to ASan
	425	* alignment restrictions.
	426	*
	427	* \note This function is not thread-safe because no two threads can poison or
	428	* unpoison memory in the same memory region simultaneously.
	429	*
	430	* \param addr Start of memory region.
	431	* \param size Size of memory region. */
	432	void __asan_poison_memory_region(void const volatile *addr, size_t size);
	433
	434	/**
	435	* Marks a memory region (<c>[addr, addr+size)</c>) as addressable.
	436	*
	437	* This memory must be previously allocated by your program. Accessing
	438	* addresses in this region is allowed until this region is poisoned again.
	439	* This function could unpoison a super-region of <c>[addr, addr+size)</c> due
440	* to ASan alignment restrictions.
441	*
442	* \note This function is not thread-safe because no two threads can
443	* poison or unpoison memory in the same memory region simultaneously.
444	*
445	* \param addr Start of memory region.
446	* \param size Size of memory region. */
447	void __asan_unpoison_memory_region(void const volatile *addr, size_t size);
448	#endif
449
450	#endif /* ZSTD_COMPILER_H */