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Diffstat (limited to 'include/ruby/atomic.h')
| -rw-r--r-- | include/ruby/atomic.h | 890 |
1 files changed, 890 insertions, 0 deletions
diff --git a/include/ruby/atomic.h b/include/ruby/atomic.h new file mode 100644 index 0000000000..3eb80fbf7d --- /dev/null +++ b/include/ruby/atomic.h @@ -0,0 +1,890 @@ +#ifndef RUBY_ATOMIC_H /*-*-C++-*-vi:se ft=cpp:*/ +#define RUBY_ATOMIC_H +/** + * @file + * @author Ruby developers <ruby-core@ruby-lang.org> + * @copyright This file is a part of the programming language Ruby. + * Permission is hereby granted, to either redistribute and/or + * modify this file, provided that the conditions mentioned in the + * file COPYING are met. Consult the file for details. + * @warning Symbols prefixed with either `RBIMPL` or `rbimpl` are + * implementation details. Don't take them as canon. They could + * rapidly appear then vanish. The name (path) of this header file + * is also an implementation detail. Do not expect it to persist + * at the place it is now. Developers are free to move it anywhere + * anytime at will. + * @note To ruby-core: remember that this header can be possibly + * recursively included from extension libraries written in C++. + * Do not expect for instance `__VA_ARGS__` is always available. + * We assume C99 for ruby itself but we don't assume languages of + * extension libraries. They could be written in C++98. + * @brief Atomic operations + * + * Basically, if we could assume either C11 or C++11, these macros are just + * redundant. Sadly we cannot. We have to do them ourselves. + */ + +#include "ruby/internal/config.h" + +#ifdef STDC_HEADERS +# include <stddef.h> /* size_t */ +#endif + +#ifdef HAVE_SYS_TYPES_H +# include <sys/types.h> /* ssize_t */ +#endif + +#if RBIMPL_COMPILER_SINCE(MSVC, 13, 0, 0) +# pragma intrinsic(_InterlockedOr) +#elif defined(__sun) && defined(HAVE_ATOMIC_H) +# include <atomic.h> +#endif + +#include "ruby/assert.h" +#include "ruby/backward/2/limits.h" +#include "ruby/internal/attr/artificial.h" +#include "ruby/internal/attr/noalias.h" +#include "ruby/internal/attr/nonnull.h" +#include "ruby/internal/compiler_since.h" +#include "ruby/internal/cast.h" +#include "ruby/internal/value.h" +#include "ruby/internal/static_assert.h" +#include "ruby/internal/stdbool.h" + +/* + * Asserts that your environment supports more than one atomic types. These + * days systems tend to have such property (C11 was a standard of decades ago, + * right?) but we still support older ones. + */ +#if defined(__DOXYGEN__) || defined(HAVE_GCC_ATOMIC_BUILTINS) || defined(HAVE_GCC_SYNC_BUILTINS) +# define RUBY_ATOMIC_GENERIC_MACRO 1 +#endif + +/** + * Type that is eligible for atomic operations. Depending on your host + * platform you might have more than one such type, but we choose one of them + * anyways. + */ +#if defined(__DOXYGEN__) +using rb_atomic_t = std::atomic<unsigned>; +#elif defined(HAVE_GCC_ATOMIC_BUILTINS) +typedef unsigned int rb_atomic_t; +#elif defined(HAVE_GCC_SYNC_BUILTINS) +typedef unsigned int rb_atomic_t; +#elif defined(_WIN32) +typedef LONG rb_atomic_t; +#elif defined(__sun) && defined(HAVE_ATOMIC_H) +typedef unsigned int rb_atomic_t; +#else +# error No atomic operation found +#endif + +/** + * Atomically replaces the value pointed by `var` with the result of addition + * of `val` to the old value of `var`. + * + * @param var A variable of ::rb_atomic_t. + * @param val Value to add. + * @return What was stored in `var` before the addition. + * @post `var` holds `var + val`. + */ +#define RUBY_ATOMIC_FETCH_ADD(var, val) rbimpl_atomic_fetch_add(&(var), (val)) + +/** + * Atomically replaces the value pointed by `var` with the result of + * subtraction of `val` to the old value of `var`. + * + * @param var A variable of ::rb_atomic_t. + * @param val Value to subtract. + * @return What was stored in `var` before the subtraction. + * @post `var` holds `var - val`. + */ +#define RUBY_ATOMIC_FETCH_SUB(var, val) rbimpl_atomic_fetch_sub(&(var), (val)) + +/** + * Atomically replaces the value pointed by `var` with the result of + * bitwise OR between `val` and the old value of `var`. + * + * @param var A variable of ::rb_atomic_t. + * @param val Value to mix. + * @return void + * @post `var` holds `var | val`. + * @note For portability, this macro can return void. + */ +#define RUBY_ATOMIC_OR(var, val) rbimpl_atomic_or(&(var), (val)) + +/** + * Atomically replaces the value pointed by `var` with `val`. This is just an + * assignment, but you can additionally know the previous value. + * + * @param var A variable of ::rb_atomic_t. + * @param val Value to set. + * @return What was stored in `var` before the assignment. + * @post `var` holds `val`. + */ +#define RUBY_ATOMIC_EXCHANGE(var, val) rbimpl_atomic_exchange(&(var), (val)) + +/** + * Atomic compare-and-swap. This stores `val` to `var` if and only if the + * assignment changes the value of `var` from `oldval` to `newval`. You can + * detect whether the assignment happened or not using the return value. + * + * @param var A variable of ::rb_atomic_t. + * @param oldval Expected value of `var` before the assignment. + * @param newval What you want to store at `var`. + * @retval oldval Successful assignment (`var` is now `newval`). + * @retval otherwise Something else is at `var`; not updated. + */ +#define RUBY_ATOMIC_CAS(var, oldval, newval) \ + rbimpl_atomic_cas(&(var), (oldval), (newval)) + +/** + * Identical to #RUBY_ATOMIC_EXCHANGE, except for the return type. + * + * @param var A variable of ::rb_atomic_t. + * @param val Value to set. + * @return void + * @post `var` holds `val`. + */ +#define RUBY_ATOMIC_SET(var, val) rbimpl_atomic_set(&(var), (val)) + +/** + * Identical to #RUBY_ATOMIC_FETCH_ADD, except for the return type. + * + * @param var A variable of ::rb_atomic_t. + * @param val Value to add. + * @return void + * @post `var` holds `var + val`. + */ +#define RUBY_ATOMIC_ADD(var, val) rbimpl_atomic_add(&(var), (val)) + +/** + * Identical to #RUBY_ATOMIC_FETCH_SUB, except for the return type. + * + * @param var A variable of ::rb_atomic_t. + * @param val Value to subtract. + * @return void + * @post `var` holds `var - val`. + */ +#define RUBY_ATOMIC_SUB(var, val) rbimpl_atomic_sub(&(var), (val)) + +/** + * Atomically increments the value pointed by `var`. + * + * @param var A variable of ::rb_atomic_t. + * @return void + * @post `var` holds `var + 1`. + */ +#define RUBY_ATOMIC_INC(var) rbimpl_atomic_inc(&(var)) + +/** + * Atomically decrements the value pointed by `var`. + * + * @param var A variable of ::rb_atomic_t. + * @return void + * @post `var` holds `var - 1`. + */ +#define RUBY_ATOMIC_DEC(var) rbimpl_atomic_dec(&(var)) + +/** + * Identical to #RUBY_ATOMIC_INC, except it expects its argument is `size_t`. + * There are cases where ::rb_atomic_t is 32bit while `size_t` is 64bit. This + * should be used for size related operations to support such platforms. + * + * @param var A variable of `size_t`. + * @return void + * @post `var` holds `var + 1`. + */ +#define RUBY_ATOMIC_SIZE_INC(var) rbimpl_atomic_size_inc(&(var)) + +/** + * Identical to #RUBY_ATOMIC_DEC, except it expects its argument is `size_t`. + * There are cases where ::rb_atomic_t is 32bit while `size_t` is 64bit. This + * should be used for size related operations to support such platforms. + * + * @param var A variable of `size_t`. + * @return void + * @post `var` holds `var - 1`. + */ +#define RUBY_ATOMIC_SIZE_DEC(var) rbimpl_atomic_size_dec(&(var)) + +/** + * Identical to #RUBY_ATOMIC_EXCHANGE, except it expects its arguments are + * `size_t`. There are cases where ::rb_atomic_t is 32bit while `size_t` is + * 64bit. This should be used for size related operations to support such + * platforms. + * + * @param var A variable of `size_t`. + * @param val Value to set. + * @return What was stored in `var` before the assignment. + * @post `var` holds `val`. + */ +#define RUBY_ATOMIC_SIZE_EXCHANGE(var, val) \ + rbimpl_atomic_size_exchange(&(var), (val)) + +/** + * Identical to #RUBY_ATOMIC_CAS, except it expects its arguments are `size_t`. + * There are cases where ::rb_atomic_t is 32bit while `size_t` is 64bit. This + * should be used for size related operations to support such platforms. + * + * @param var A variable of `size_t`. + * @param oldval Expected value of `var` before the assignment. + * @param newval What you want to store at `var`. + * @retval oldval Successful assignment (`var` is now `newval`). + * @retval otherwise Something else is at `var`; not updated. + */ +#define RUBY_ATOMIC_SIZE_CAS(var, oldval, newval) \ + rbimpl_atomic_size_cas(&(var), (oldval), (newval)) + +/** + * Identical to #RUBY_ATOMIC_ADD, except it expects its arguments are `size_t`. + * There are cases where ::rb_atomic_t is 32bit while `size_t` is 64bit. This + * should be used for size related operations to support such platforms. + * + * @param var A variable of `size_t`. + * @param val Value to add. + * @return void + * @post `var` holds `var + val`. + */ +#define RUBY_ATOMIC_SIZE_ADD(var, val) rbimpl_atomic_size_add(&(var), (val)) + +/** + * Identical to #RUBY_ATOMIC_SUB, except it expects its arguments are `size_t`. + * There are cases where ::rb_atomic_t is 32bit while `size_t` is 64bit. This + * should be used for size related operations to support such platforms. + * + * @param var A variable of `size_t`. + * @param val Value to subtract. + * @return void + * @post `var` holds `var - val`. + */ +#define RUBY_ATOMIC_SIZE_SUB(var, val) rbimpl_atomic_size_sub(&(var), (val)) + +/** + * Identical to #RUBY_ATOMIC_EXCHANGE, except it expects its arguments are + * `void*`. There are cases where ::rb_atomic_t is 32bit while `void*` is + * 64bit. This should be used for pointer related operations to support such + * platforms. + * + * @param var A variable of `void *`. + * @param val Value to set. + * @return What was stored in `var` before the assignment. + * @post `var` holds `val`. + * + * @internal + * + * :FIXME: this `(void*)` cast is evil! However `void*` is incompatible with + * some pointers, most notably function pointers. + */ +#define RUBY_ATOMIC_PTR_EXCHANGE(var, val) \ + RBIMPL_CAST(rbimpl_atomic_ptr_exchange((void **)&(var), (void *)val)) + +/** + * Identical to #RUBY_ATOMIC_CAS, except it expects its arguments are `void*`. + * There are cases where ::rb_atomic_t is 32bit while `void*` is 64bit. This + * should be used for size related operations to support such platforms. + * + * @param var A variable of `void*`. + * @param oldval Expected value of `var` before the assignment. + * @param newval What you want to store at `var`. + * @retval oldval Successful assignment (`var` is now `newval`). + * @retval otherwise Something else is at `var`; not updated. + */ +#define RUBY_ATOMIC_PTR_CAS(var, oldval, newval) \ + RBIMPL_CAST(rbimpl_atomic_ptr_cas((void **)&(var), (oldval), (newval))) + +/** + * Identical to #RUBY_ATOMIC_EXCHANGE, except it expects its arguments are + * ::VALUE. There are cases where ::rb_atomic_t is 32bit while ::VALUE is + * 64bit. This should be used for pointer related operations to support such + * platforms. + * + * @param var A variable of ::VALUE. + * @param val Value to set. + * @return What was stored in `var` before the assignment. + * @post `var` holds `val`. + */ +#define RUBY_ATOMIC_VALUE_EXCHANGE(var, val) \ + rbimpl_atomic_value_exchange(&(var), (val)) + +/** + * Identical to #RUBY_ATOMIC_CAS, except it expects its arguments are ::VALUE. + * There are cases where ::rb_atomic_t is 32bit while ::VALUE is 64bit. This + * should be used for size related operations to support such platforms. + * + * @param var A variable of `void*`. + * @param oldval Expected value of `var` before the assignment. + * @param newval What you want to store at `var`. + * @retval oldval Successful assignment (`var` is now `newval`). + * @retval otherwise Something else is at `var`; not updated. + */ +#define RUBY_ATOMIC_VALUE_CAS(var, oldval, newval) \ + rbimpl_atomic_value_cas(&(var), (oldval), (newval)) + +/** @cond INTERNAL_MACRO */ +RBIMPL_ATTR_ARTIFICIAL() +RBIMPL_ATTR_NOALIAS() +RBIMPL_ATTR_NONNULL((1)) +static inline rb_atomic_t +rbimpl_atomic_fetch_add(volatile rb_atomic_t *ptr, rb_atomic_t val) +{ +#if 0 + +#elif defined(HAVE_GCC_ATOMIC_BUILTINS) + return __atomic_fetch_add(ptr, val, __ATOMIC_SEQ_CST); + +#elif defined(HAVE_GCC_SYNC_BUILTINS) + return __sync_fetch_and_add(ptr, val); + +#elif defined(_WIN32) + return InterlockedExchangeAdd(ptr, val); + +#elif defined(__sun) && defined(HAVE_ATOMIC_H) + /* + * `atomic_add_int_nv` takes its second argument as `int`! Meanwhile our + * `rb_atomic_t` is unsigned. We cannot pass `val` as-is. We have to + * manually check integer overflow. + */ + RBIMPL_ASSERT_OR_ASSUME(val <= INT_MAX); + return atomic_add_int_nv(ptr, val) - val; + +#else +# error Unsupported platform. +#endif +} + +RBIMPL_ATTR_ARTIFICIAL() +RBIMPL_ATTR_NOALIAS() +RBIMPL_ATTR_NONNULL((1)) +static inline void +rbimpl_atomic_add(volatile rb_atomic_t *ptr, rb_atomic_t val) +{ +#if 0 + +#elif defined(HAVE_GCC_ATOMIC_BUILTINS) + /* + * GCC on amd64 is smart enough to detect this `__atomic_add_fetch`'s + * return value is not used, then compiles it into single `LOCK ADD` + * instruction. + */ + __atomic_add_fetch(ptr, val, __ATOMIC_SEQ_CST); + +#elif defined(HAVE_GCC_SYNC_BUILTINS) + __sync_add_and_fetch(ptr, val); + +#elif defined(_WIN32) + /* + * `InterlockedExchangeAdd` is `LOCK XADD`. It seems there also is + * `_InterlockedAdd` intrinsic in ARM Windows but not for x86? Sticking to + * `InterlockedExchangeAdd` for better portability. + */ + InterlockedExchangeAdd(ptr, val); + +#elif defined(__sun) && defined(HAVE_ATOMIC_H) + /* Ditto for `atomic_add_int_nv`. */ + RBIMPL_ASSERT_OR_ASSUME(val <= INT_MAX); + atomic_add_int(ptr, val); + +#else +# error Unsupported platform. +#endif +} + +RBIMPL_ATTR_ARTIFICIAL() +RBIMPL_ATTR_NOALIAS() +RBIMPL_ATTR_NONNULL((1)) +static inline void +rbimpl_atomic_size_add(volatile size_t *ptr, size_t val) +{ +#if 0 + +#elif defined(HAVE_GCC_ATOMIC_BUILTINS) + __atomic_add_fetch(ptr, val, __ATOMIC_SEQ_CST); + +#elif defined(HAVE_GCC_SYNC_BUILTINS) + __sync_add_and_fetch(ptr, val); + +#elif defined(_WIN32) && defined(_M_AMD64) + /* Ditto for `InterlockeExchangedAdd`. */ + InterlockedExchangeAdd64(ptr, val); + +#elif defined(__sun) && defined(HAVE_ATOMIC_H) && (defined(_LP64) || defined(_I32LPx)) + /* Ditto for `atomic_add_int_nv`. */ + RBIMPL_ASSERT_OR_ASSUME(val <= LONG_MAX); + atomic_add_long(ptr, val); + +#else + RBIMPL_STATIC_ASSERT(size_of_rb_atomic_t, sizeof *ptr == sizeof(rb_atomic_t)); + + volatile rb_atomic_t *const tmp = RBIMPL_CAST((volatile rb_atomic_t *)ptr); + rbimpl_atomic_add(tmp, val); + +#endif +} + +RBIMPL_ATTR_ARTIFICIAL() +RBIMPL_ATTR_NOALIAS() +RBIMPL_ATTR_NONNULL((1)) +static inline void +rbimpl_atomic_inc(volatile rb_atomic_t *ptr) +{ +#if 0 + +#elif defined(HAVE_GCC_ATOMIC_BUILTINS) || defined(HAVE_GCC_SYNC_BUILTINS) + rbimpl_atomic_add(ptr, 1); + +#elif defined(_WIN32) + InterlockedIncrement(ptr); + +#elif defined(__sun) && defined(HAVE_ATOMIC_H) + atomic_inc_uint(ptr); + +#else + rbimpl_atomic_add(ptr, 1); + +#endif +} + +RBIMPL_ATTR_ARTIFICIAL() +RBIMPL_ATTR_NOALIAS() +RBIMPL_ATTR_NONNULL((1)) +static inline void +rbimpl_atomic_size_inc(volatile size_t *ptr) +{ +#if 0 + +#elif defined(HAVE_GCC_ATOMIC_BUILTINS) || defined(HAVE_GCC_SYNC_BUILTINS) + rbimpl_atomic_size_add(ptr, 1); + +#elif defined(_WIN32) && defined(_M_AMD64) + InterlockedIncrement64(ptr); + +#elif defined(__sun) && defined(HAVE_ATOMIC_H) && (defined(_LP64) || defined(_I32LPx)) + atomic_inc_ulong(ptr); + +#else + rbimpl_atomic_size_add(ptr, 1); + +#endif +} + +RBIMPL_ATTR_ARTIFICIAL() +RBIMPL_ATTR_NOALIAS() +RBIMPL_ATTR_NONNULL((1)) +static inline rb_atomic_t +rbimpl_atomic_fetch_sub(volatile rb_atomic_t *ptr, rb_atomic_t val) +{ +#if 0 + +#elif defined(HAVE_GCC_ATOMIC_BUILTINS) + return __atomic_fetch_sub(ptr, val, __ATOMIC_SEQ_CST); + +#elif defined(HAVE_GCC_SYNC_BUILTINS) + return __sync_fetch_and_sub(ptr, val); + +#elif defined(_WIN32) + /* rb_atomic_t is signed here! Safe to do `-val`. */ + return InterlockedExchangeAdd(ptr, -val); + +#elif defined(__sun) && defined(HAVE_ATOMIC_H) + /* Ditto for `rbimpl_atomic_fetch_add`. */ + const signed neg = -1; + RBIMPL_ASSERT_OR_ASSUME(val <= INT_MAX); + return atomic_add_int_nv(ptr, neg * val) + val; + +#else +# error Unsupported platform. +#endif +} + +RBIMPL_ATTR_ARTIFICIAL() +RBIMPL_ATTR_NOALIAS() +RBIMPL_ATTR_NONNULL((1)) +static inline void +rbimpl_atomic_sub(volatile rb_atomic_t *ptr, rb_atomic_t val) +{ +#if 0 + +#elif defined(HAVE_GCC_ATOMIC_BUILTINS) + __atomic_sub_fetch(ptr, val, __ATOMIC_SEQ_CST); + +#elif defined(HAVE_GCC_SYNC_BUILTINS) + __sync_sub_and_fetch(ptr, val); + +#elif defined(_WIN32) + InterlockedExchangeAdd(ptr, -val); + +#elif defined(__sun) && defined(HAVE_ATOMIC_H) + const signed neg = -1; + RBIMPL_ASSERT_OR_ASSUME(val <= INT_MAX); + atomic_add_int(ptr, neg * val); + +#else +# error Unsupported platform. +#endif +} + +RBIMPL_ATTR_ARTIFICIAL() +RBIMPL_ATTR_NOALIAS() +RBIMPL_ATTR_NONNULL((1)) +static inline void +rbimpl_atomic_size_sub(volatile size_t *ptr, size_t val) +{ +#if 0 + +#elif defined(HAVE_GCC_ATOMIC_BUILTINS) + __atomic_sub_fetch(ptr, val, __ATOMIC_SEQ_CST); + +#elif defined(HAVE_GCC_SYNC_BUILTINS) + __sync_sub_and_fetch(ptr, val); + +#elif defined(_WIN32) && defined(_M_AMD64) + const ssize_t neg = -1; + InterlockedExchangeAdd64(ptr, neg * val); + +#elif defined(__sun) && defined(HAVE_ATOMIC_H) && (defined(_LP64) || defined(_I32LPx)) + const signed neg = -1; + RBIMPL_ASSERT_OR_ASSUME(val <= LONG_MAX); + atomic_add_long(ptr, neg * val); + +#else + RBIMPL_STATIC_ASSERT(size_of_rb_atomic_t, sizeof *ptr == sizeof(rb_atomic_t)); + + volatile rb_atomic_t *const tmp = RBIMPL_CAST((volatile rb_atomic_t *)ptr); + rbimpl_atomic_sub(tmp, val); + +#endif +} + +RBIMPL_ATTR_ARTIFICIAL() +RBIMPL_ATTR_NOALIAS() +RBIMPL_ATTR_NONNULL((1)) +static inline void +rbimpl_atomic_dec(volatile rb_atomic_t *ptr) +{ +#if 0 + +#elif defined(HAVE_GCC_ATOMIC_BUILTINS) || defined(HAVE_GCC_SYNC_BUILTINS) + rbimpl_atomic_sub(ptr, 1); + +#elif defined(_WIN32) + InterlockedDecrement(ptr); + +#elif defined(__sun) && defined(HAVE_ATOMIC_H) + atomic_dec_uint(ptr); + +#else + rbimpl_atomic_sub(ptr, 1); + +#endif +} + +RBIMPL_ATTR_ARTIFICIAL() +RBIMPL_ATTR_NOALIAS() +RBIMPL_ATTR_NONNULL((1)) +static inline void +rbimpl_atomic_size_dec(volatile size_t *ptr) +{ +#if 0 + +#elif defined(HAVE_GCC_ATOMIC_BUILTINS) || defined(HAVE_GCC_SYNC_BUILTINS) + rbimpl_atomic_size_sub(ptr, 1); + +#elif defined(_WIN32) && defined(_M_AMD64) + InterlockedDecrement64(ptr); + +#elif defined(__sun) && defined(HAVE_ATOMIC_H) && (defined(_LP64) || defined(_I32LPx)) + atomic_dec_ulong(ptr); + +#else + rbimpl_atomic_size_sub(ptr, 1); + +#endif +} + +RBIMPL_ATTR_ARTIFICIAL() +RBIMPL_ATTR_NOALIAS() +RBIMPL_ATTR_NONNULL((1)) +static inline void +rbimpl_atomic_or(volatile rb_atomic_t *ptr, rb_atomic_t val) +{ +#if 0 + +#elif defined(HAVE_GCC_ATOMIC_BUILTINS) + __atomic_or_fetch(ptr, val, __ATOMIC_SEQ_CST); + +#elif defined(HAVE_GCC_SYNC_BUILTINS) + __sync_or_and_fetch(ptr, val); + +#elif RBIMPL_COMPILER_SINCE(MSVC, 13, 0, 0) + _InterlockedOr(ptr, val); + +#elif defined(_WIN32) && defined(__GNUC__) + /* This was for old MinGW. Maybe not needed any longer? */ + __asm__( + "lock\n\t" + "orl\t%1, %0" + : "=m"(ptr) + : "Ir"(val)); + +#elif defined(_WIN32) && defined(_M_IX86) + __asm mov eax, ptr; + __asm mov ecx, val; + __asm lock or [eax], ecx; + +#elif defined(__sun) && defined(HAVE_ATOMIC_H) + atomic_or_uint(ptr, val); + +#else +# error Unsupported platform. +#endif +} + +/* Nobody uses this but for theoretical backwards compatibility... */ +#if RBIMPL_COMPILER_BEFORE(MSVC, 13, 0, 0) +static inline rb_atomic_t +rb_w32_atomic_or(volatile rb_atomic_t *var, rb_atomic_t val) +{ + return rbimpl_atomic_or(var, val); +} +#endif + +RBIMPL_ATTR_ARTIFICIAL() +RBIMPL_ATTR_NOALIAS() +RBIMPL_ATTR_NONNULL((1)) +static inline rb_atomic_t +rbimpl_atomic_exchange(volatile rb_atomic_t *ptr, rb_atomic_t val) +{ +#if 0 + +#elif defined(HAVE_GCC_ATOMIC_BUILTINS) + return __atomic_exchange_n(ptr, val, __ATOMIC_SEQ_CST); + +#elif defined(HAVE_GCC_SYNC_BUILTINS) + return __sync_lock_test_and_set(ptr, val); + +#elif defined(_WIN32) + return InterlockedExchange(ptr, val); + +#elif defined(__sun) && defined(HAVE_ATOMIC_H) + return atomic_swap_uint(ptr, val); + +#else +# error Unsupported platform. +#endif +} + +RBIMPL_ATTR_ARTIFICIAL() +RBIMPL_ATTR_NOALIAS() +RBIMPL_ATTR_NONNULL((1)) +static inline size_t +rbimpl_atomic_size_exchange(volatile size_t *ptr, size_t val) +{ +#if 0 + +#elif defined(HAVE_GCC_ATOMIC_BUILTINS) + return __atomic_exchange_n(ptr, val, __ATOMIC_SEQ_CST); + +#elif defined(HAVE_GCC_SYNC_BUILTINS) + return __sync_lock_test_and_set(ptr, val); + +#elif defined(_WIN32) && defined(_M_AMD64) + return InterlockedExchange64(ptr, val); + +#elif defined(__sun) && defined(HAVE_ATOMIC_H) && (defined(_LP64) || defined(_I32LPx)) + return atomic_swap_ulong(ptr, val); + +#else + RBIMPL_STATIC_ASSERT(size_of_size_t, sizeof *ptr == sizeof(rb_atomic_t)); + + volatile rb_atomic_t *const tmp = RBIMPL_CAST((volatile rb_atomic_t *)ptr); + const rb_atomic_t ret = rbimpl_atomic_exchange(tmp, val); + return RBIMPL_CAST((size_t)ret); + +#endif +} + +RBIMPL_ATTR_ARTIFICIAL() +RBIMPL_ATTR_NOALIAS() +RBIMPL_ATTR_NONNULL((1)) +static inline void * +rbimpl_atomic_ptr_exchange(void *volatile *ptr, const void *val) +{ +#if 0 + +#elif defined(InterlockedExchangePointer) + /* const_cast */ + PVOID *pptr = RBIMPL_CAST((PVOID *)ptr); + PVOID pval = RBIMPL_CAST((PVOID)val); + return InterlockedExchangePointer(pptr, pval); + +#elif defined(__sun) && defined(HAVE_ATOMIC_H) + return atomic_swap_ptr(ptr, RBIMPL_CAST((void *)val)); + +#else + RBIMPL_STATIC_ASSERT(sizeof_voidp, sizeof *ptr == sizeof(size_t)); + + const size_t sval = RBIMPL_CAST((size_t)val); + volatile size_t *const sptr = RBIMPL_CAST((volatile size_t *)ptr); + const size_t sret = rbimpl_atomic_size_exchange(sptr, sval); + return RBIMPL_CAST((void *)sret); + +#endif +} + +RBIMPL_ATTR_ARTIFICIAL() +RBIMPL_ATTR_NOALIAS() +RBIMPL_ATTR_NONNULL((1)) +static inline VALUE +rbimpl_atomic_value_exchange(volatile VALUE *ptr, VALUE val) +{ + RBIMPL_STATIC_ASSERT(sizeof_value, sizeof *ptr == sizeof(size_t)); + + const size_t sval = RBIMPL_CAST((size_t)val); + volatile size_t *const sptr = RBIMPL_CAST((volatile size_t *)ptr); + const size_t sret = rbimpl_atomic_size_exchange(sptr, sval); + return RBIMPL_CAST((VALUE)sret); +} + +RBIMPL_ATTR_ARTIFICIAL() +RBIMPL_ATTR_NOALIAS() +RBIMPL_ATTR_NONNULL((1)) +static inline void +rbimpl_atomic_set(volatile rb_atomic_t *ptr, rb_atomic_t val) +{ +#if 0 + +#elif defined(HAVE_GCC_ATOMIC_BUILTINS) + __atomic_store_n(ptr, val, __ATOMIC_SEQ_CST); + +#else + /* Maybe std::atomic<rb_atomic_t>::store can be faster? */ + rbimpl_atomic_exchange(ptr, val); + +#endif +} + +RBIMPL_ATTR_ARTIFICIAL() +RBIMPL_ATTR_NOALIAS() +RBIMPL_ATTR_NONNULL((1)) +static inline rb_atomic_t +rbimpl_atomic_cas(volatile rb_atomic_t *ptr, rb_atomic_t oldval, rb_atomic_t newval) +{ +#if 0 + +#elif defined(HAVE_GCC_ATOMIC_BUILTINS) + __atomic_compare_exchange_n( + ptr, &oldval, newval, 0, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST); + return oldval; + +#elif defined(HAVE_GCC_SYNC_BUILTINS) + return __sync_val_compare_and_swap(ptr, oldval, newval); + +#elif RBIMPL_COMPILER_SINCE(MSVC, 13, 0, 0) + return InterlockedCompareExchange(ptr, newval, oldval); + +#elif defined(_WIN32) + PVOID *pptr = RBIMPL_CAST((PVOID *)ptr); + PVOID pold = RBIMPL_CAST((PVOID)oldval); + PVOID pnew = RBIMPL_CAST((PVOID)newval); + PVOID pret = InterlockedCompareExchange(pptr, pnew, pold); + return RBIMPL_CAST((rb_atomic_t)pret); + +#elif defined(__sun) && defined(HAVE_ATOMIC_H) + return atomic_cas_uint(ptr, oldval, newval); + +#else +# error Unsupported platform. +#endif +} + +/* Nobody uses this but for theoretical backwards compatibility... */ +#if RBIMPL_COMPILER_BEFORE(MSVC, 13, 0, 0) +static inline rb_atomic_t +rb_w32_atomic_cas(volatile rb_atomic_t *var, rb_atomic_t oldval, rb_atomic_t newval) +{ + return rbimpl_atomic_cas(var, oldval, newval); +} +#endif + +RBIMPL_ATTR_ARTIFICIAL() +RBIMPL_ATTR_NOALIAS() +RBIMPL_ATTR_NONNULL((1)) +static inline size_t +rbimpl_atomic_size_cas(volatile size_t *ptr, size_t oldval, size_t newval) +{ +#if 0 + +#elif defined(HAVE_GCC_ATOMIC_BUILTINS) + __atomic_compare_exchange_n( + ptr, &oldval, newval, 0, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST); + return oldval; + +#elif defined(HAVE_GCC_SYNC_BUILTINS) + return __sync_val_compare_and_swap(ptr, oldval, newval); + +#elif defined(_WIN32) && defined(_M_AMD64) + return InterlockedCompareExchange64(ptr, newval, oldval); + +#elif defined(__sun) && defined(HAVE_ATOMIC_H) && (defined(_LP64) || defined(_I32LPx)) + return atomic_cas_ulong(ptr, oldval, newval); + +#else + RBIMPL_STATIC_ASSERT(size_of_size_t, sizeof *ptr == sizeof(rb_atomic_t)); + + volatile rb_atomic_t *tmp = RBIMPL_CAST((volatile rb_atomic_t *)ptr); + return rbimpl_atomic_cas(tmp, oldval, newval); + +#endif +} + +RBIMPL_ATTR_ARTIFICIAL() +RBIMPL_ATTR_NOALIAS() +RBIMPL_ATTR_NONNULL((1)) +static inline void * +rbimpl_atomic_ptr_cas(void **ptr, const void *oldval, const void *newval) +{ +#if 0 + +#elif defined(InterlockedExchangePointer) + /* ... Can we say that InterlockedCompareExchangePtr surly exists when + * InterlockedExchangePointer is defined? Seems so but...?*/ + PVOID *pptr = RBIMPL_CAST((PVOID *)ptr); + PVOID pold = RBIMPL_CAST((PVOID)oldval); + PVOID pnew = RBIMPL_CAST((PVOID)newval); + return InterlockedCompareExchangePointer(pptr, pnew, pold); + +#elif defined(__sun) && defined(HAVE_ATOMIC_H) + void *pold = RBIMPL_CAST((void *)oldval); + void *pnew = RBIMPL_CAST((void *)newval); + return atomic_cas_ptr(ptr, pold, pnew); + + +#else + RBIMPL_STATIC_ASSERT(sizeof_voidp, sizeof *ptr == sizeof(size_t)); + + const size_t snew = RBIMPL_CAST((size_t)newval); + const size_t sold = RBIMPL_CAST((size_t)oldval); + volatile size_t *const sptr = RBIMPL_CAST((volatile size_t *)ptr); + const size_t sret = rbimpl_atomic_size_cas(sptr, sold, snew); + return RBIMPL_CAST((void *)sret); + +#endif +} + +RBIMPL_ATTR_ARTIFICIAL() +RBIMPL_ATTR_NOALIAS() +RBIMPL_ATTR_NONNULL((1)) +static inline VALUE +rbimpl_atomic_value_cas(volatile VALUE *ptr, VALUE oldval, VALUE newval) +{ + RBIMPL_STATIC_ASSERT(sizeof_value, sizeof *ptr == sizeof(size_t)); + + const size_t snew = RBIMPL_CAST((size_t)newval); + const size_t sold = RBIMPL_CAST((size_t)oldval); + volatile size_t *const sptr = RBIMPL_CAST((volatile size_t *)ptr); + const size_t sret = rbimpl_atomic_size_cas(sptr, sold, snew); + return RBIMPL_CAST((VALUE)sret); +} +/** @endcond */ +#endif /* RUBY_ATOMIC_H */ |