| // -*- C++ -*- |
| |
| // Copyright (C) 2007, 2008, 2009 Free Software Foundation, Inc. |
| // |
| // This file is part of the GNU ISO C++ Library. This library is free |
| // software; you can redistribute it and/or modify it under the terms |
| // of the GNU General Public License as published by the Free Software |
| // Foundation; either version 3, or (at your option) any later |
| // version. |
| |
| // This library is distributed in the hope that it will be useful, but |
| // WITHOUT ANY WARRANTY; without even the implied warranty of |
| // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| // General Public License for more details. |
| |
| // Under Section 7 of GPL version 3, you are granted additional |
| // permissions described in the GCC Runtime Library Exception, version |
| // 3.1, as published by the Free Software Foundation. |
| |
| // You should have received a copy of the GNU General Public License and |
| // a copy of the GCC Runtime Library Exception along with this program; |
| // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
| // <http://www.gnu.org/licenses/>. |
| |
| /** @file parallel/compatibility.h |
| * @brief Compatibility layer, mostly concerned with atomic operations. |
| * This file is a GNU parallel extension to the Standard C++ Library. |
| */ |
| |
| // Written by Felix Putze. |
| |
| #ifndef _GLIBCXX_PARALLEL_COMPATIBILITY_H |
| #define _GLIBCXX_PARALLEL_COMPATIBILITY_H 1 |
| |
| #include <parallel/types.h> |
| #include <parallel/base.h> |
| |
| #if defined(__SUNPRO_CC) && defined(__sparc) |
| #include <sys/atomic.h> |
| #endif |
| |
| #if !defined(_WIN32) || defined (__CYGWIN__) |
| #include <sched.h> |
| #endif |
| |
| #if defined(_MSC_VER) |
| #include <Windows.h> |
| #include <intrin.h> |
| #undef max |
| #undef min |
| #endif |
| |
| #ifdef __MINGW32__ |
| // Including <windows.h> will drag in all the windows32 names. Since |
| // that can cause user code portability problems, we just declare the |
| // one needed function here. |
| extern "C" |
| __attribute((dllimport)) void __attribute__((stdcall)) Sleep (unsigned long); |
| #endif |
| |
| namespace __gnu_parallel |
| { |
| #if defined(__ICC) |
| template<typename must_be_int = int> |
| int32 faa32(int32* x, int32 inc) |
| { |
| asm volatile("lock xadd %0,%1" |
| : "=r" (inc), "=m" (*x) |
| : "0" (inc) |
| : "memory"); |
| return inc; |
| } |
| #if defined(__x86_64) |
| template<typename must_be_int = int> |
| int64 faa64(int64* x, int64 inc) |
| { |
| asm volatile("lock xadd %0,%1" |
| : "=r" (inc), "=m" (*x) |
| : "0" (inc) |
| : "memory"); |
| return inc; |
| } |
| #endif |
| #endif |
| |
| // atomic functions only work on integers |
| |
| /** @brief Add a value to a variable, atomically. |
| * |
| * Implementation is heavily platform-dependent. |
| * @param ptr Pointer to a 32-bit signed integer. |
| * @param addend Value to add. |
| */ |
| inline int32 |
| fetch_and_add_32(volatile int32* ptr, int32 addend) |
| { |
| #if defined(__ICC) //x86 version |
| return _InterlockedExchangeAdd((void*)ptr, addend); |
| #elif defined(__ECC) //IA-64 version |
| return _InterlockedExchangeAdd((void*)ptr, addend); |
| #elif defined(__ICL) || defined(_MSC_VER) |
| return _InterlockedExchangeAdd(reinterpret_cast<volatile long*>(ptr), |
| addend); |
| #elif defined(__GNUC__) |
| return __sync_fetch_and_add(ptr, addend); |
| #elif defined(__SUNPRO_CC) && defined(__sparc) |
| volatile int32 before, after; |
| do |
| { |
| before = *ptr; |
| after = before + addend; |
| } while (atomic_cas_32((volatile unsigned int*)ptr, before, |
| after) != before); |
| return before; |
| #else //fallback, slow |
| #pragma message("slow fetch_and_add_32") |
| int32 res; |
| #pragma omp critical |
| { |
| res = *ptr; |
| *(ptr) += addend; |
| } |
| return res; |
| #endif |
| } |
| |
| /** @brief Add a value to a variable, atomically. |
| * |
| * Implementation is heavily platform-dependent. |
| * @param ptr Pointer to a 64-bit signed integer. |
| * @param addend Value to add. |
| */ |
| inline int64 |
| fetch_and_add_64(volatile int64* ptr, int64 addend) |
| { |
| #if defined(__ICC) && defined(__x86_64) //x86 version |
| return faa64<int>((int64*)ptr, addend); |
| #elif defined(__ECC) //IA-64 version |
| return _InterlockedExchangeAdd64((void*)ptr, addend); |
| #elif defined(__ICL) || defined(_MSC_VER) |
| #ifndef _WIN64 |
| _GLIBCXX_PARALLEL_ASSERT(false); //not available in this case |
| return 0; |
| #else |
| return _InterlockedExchangeAdd64(ptr, addend); |
| #endif |
| #elif defined(__GNUC__) && defined(__x86_64) |
| return __sync_fetch_and_add(ptr, addend); |
| #elif defined(__GNUC__) && defined(__i386) && \ |
| (defined(__i686) || defined(__pentium4) || defined(__athlon)) |
| return __sync_fetch_and_add(ptr, addend); |
| #elif defined(__SUNPRO_CC) && defined(__sparc) |
| volatile int64 before, after; |
| do |
| { |
| before = *ptr; |
| after = before + addend; |
| } while (atomic_cas_64((volatile unsigned long long*)ptr, before, |
| after) != before); |
| return before; |
| #else //fallback, slow |
| #if defined(__GNUC__) && defined(__i386) |
| // XXX doesn't work with -march=native |
| //#warning "please compile with -march=i686 or better" |
| #endif |
| #pragma message("slow fetch_and_add_64") |
| int64 res; |
| #pragma omp critical |
| { |
| res = *ptr; |
| *(ptr) += addend; |
| } |
| return res; |
| #endif |
| } |
| |
| /** @brief Add a value to a variable, atomically. |
| * |
| * Implementation is heavily platform-dependent. |
| * @param ptr Pointer to a signed integer. |
| * @param addend Value to add. |
| */ |
| template<typename T> |
| inline T |
| fetch_and_add(volatile T* ptr, T addend) |
| { |
| if (sizeof(T) == sizeof(int32)) |
| return (T)fetch_and_add_32((volatile int32*) ptr, (int32)addend); |
| else if (sizeof(T) == sizeof(int64)) |
| return (T)fetch_and_add_64((volatile int64*) ptr, (int64)addend); |
| else |
| _GLIBCXX_PARALLEL_ASSERT(false); |
| } |
| |
| |
| #if defined(__ICC) |
| |
| template<typename must_be_int = int> |
| inline int32 |
| cas32(volatile int32* ptr, int32 old, int32 nw) |
| { |
| int32 before; |
| __asm__ __volatile__("lock; cmpxchgl %1,%2" |
| : "=a"(before) |
| : "q"(nw), "m"(*(volatile long long*)(ptr)), "0"(old) |
| : "memory"); |
| return before; |
| } |
| |
| #if defined(__x86_64) |
| template<typename must_be_int = int> |
| inline int64 |
| cas64(volatile int64 *ptr, int64 old, int64 nw) |
| { |
| int64 before; |
| __asm__ __volatile__("lock; cmpxchgq %1,%2" |
| : "=a"(before) |
| : "q"(nw), "m"(*(volatile long long*)(ptr)), "0"(old) |
| : "memory"); |
| return before; |
| } |
| #endif |
| |
| #endif |
| |
| /** @brief Compare @c *ptr and @c comparand. If equal, let @c |
| * *ptr=replacement and return @c true, return @c false otherwise. |
| * |
| * Implementation is heavily platform-dependent. |
| * @param ptr Pointer to 32-bit signed integer. |
| * @param comparand Compare value. |
| * @param replacement Replacement value. |
| */ |
| inline bool |
| compare_and_swap_32(volatile int32* ptr, int32 comparand, int32 replacement) |
| { |
| #if defined(__ICC) //x86 version |
| return _InterlockedCompareExchange((void*)ptr, replacement, |
| comparand) == comparand; |
| #elif defined(__ECC) //IA-64 version |
| return _InterlockedCompareExchange((void*)ptr, replacement, |
| comparand) == comparand; |
| #elif defined(__ICL) || defined(_MSC_VER) |
| return _InterlockedCompareExchange(reinterpret_cast<volatile long*>(ptr), |
| replacement, comparand) == comparand; |
| #elif defined(__GNUC__) |
| return __sync_bool_compare_and_swap(ptr, comparand, replacement); |
| #elif defined(__SUNPRO_CC) && defined(__sparc) |
| return atomic_cas_32((volatile unsigned int*)ptr, comparand, |
| replacement) == comparand; |
| #else |
| #pragma message("slow compare_and_swap_32") |
| bool res = false; |
| #pragma omp critical |
| { |
| if (*ptr == comparand) |
| { |
| *ptr = replacement; |
| res = true; |
| } |
| } |
| return res; |
| #endif |
| } |
| |
| /** @brief Compare @c *ptr and @c comparand. If equal, let @c |
| * *ptr=replacement and return @c true, return @c false otherwise. |
| * |
| * Implementation is heavily platform-dependent. |
| * @param ptr Pointer to 64-bit signed integer. |
| * @param comparand Compare value. |
| * @param replacement Replacement value. |
| */ |
| inline bool |
| compare_and_swap_64(volatile int64* ptr, int64 comparand, int64 replacement) |
| { |
| #if defined(__ICC) && defined(__x86_64) //x86 version |
| return cas64<int>(ptr, comparand, replacement) == comparand; |
| #elif defined(__ECC) //IA-64 version |
| return _InterlockedCompareExchange64((void*)ptr, replacement, |
| comparand) == comparand; |
| #elif defined(__ICL) || defined(_MSC_VER) |
| #ifndef _WIN64 |
| _GLIBCXX_PARALLEL_ASSERT(false); //not available in this case |
| return 0; |
| #else |
| return _InterlockedCompareExchange64(ptr, replacement, |
| comparand) == comparand; |
| #endif |
| |
| #elif defined(__GNUC__) && defined(__x86_64) |
| return __sync_bool_compare_and_swap(ptr, comparand, replacement); |
| #elif defined(__GNUC__) && defined(__i386) && \ |
| (defined(__i686) || defined(__pentium4) || defined(__athlon)) |
| return __sync_bool_compare_and_swap(ptr, comparand, replacement); |
| #elif defined(__SUNPRO_CC) && defined(__sparc) |
| return atomic_cas_64((volatile unsigned long long*)ptr, |
| comparand, replacement) == comparand; |
| #else |
| #if defined(__GNUC__) && defined(__i386) |
| // XXX -march=native |
| //#warning "please compile with -march=i686 or better" |
| #endif |
| #pragma message("slow compare_and_swap_64") |
| bool res = false; |
| #pragma omp critical |
| { |
| if (*ptr == comparand) |
| { |
| *ptr = replacement; |
| res = true; |
| } |
| } |
| return res; |
| #endif |
| } |
| |
| /** @brief Compare @c *ptr and @c comparand. If equal, let @c |
| * *ptr=replacement and return @c true, return @c false otherwise. |
| * |
| * Implementation is heavily platform-dependent. |
| * @param ptr Pointer to signed integer. |
| * @param comparand Compare value. |
| * @param replacement Replacement value. */ |
| template<typename T> |
| inline bool |
| compare_and_swap(volatile T* ptr, T comparand, T replacement) |
| { |
| if (sizeof(T) == sizeof(int32)) |
| return compare_and_swap_32((volatile int32*) ptr, (int32)comparand, (int32)replacement); |
| else if (sizeof(T) == sizeof(int64)) |
| return compare_and_swap_64((volatile int64*) ptr, (int64)comparand, (int64)replacement); |
| else |
| _GLIBCXX_PARALLEL_ASSERT(false); |
| } |
| |
| /** @brief Yield the control to another thread, without waiting for |
| the end to the time slice. */ |
| inline void |
| yield() |
| { |
| #if defined (_WIN32) && !defined (__CYGWIN__) |
| Sleep(0); |
| #else |
| sched_yield(); |
| #endif |
| } |
| } // end namespace |
| |
| #endif /* _GLIBCXX_PARALLEL_COMPATIBILITY_H */ |