1 /* reducer_impl.h -*-C++-*- 2 * 3 ************************************************************************* 4 * 5 * @copyright 6 * Copyright (C) 2009-2013, Intel Corporation 7 * All rights reserved. 8 * 9 * @copyright 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 14 * * Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * * Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in 18 * the documentation and/or other materials provided with the 19 * distribution. 20 * * Neither the name of Intel Corporation nor the names of its 21 * contributors may be used to endorse or promote products derived 22 * from this software without specific prior written permission. 23 * 24 * @copyright 25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 26 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 27 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 28 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 29 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 30 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 31 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 32 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 33 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY 35 * WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 **************************************************************************/ 38 39 /** 40 * @file reducer_impl.h 41 * 42 * @brief Functions to implement reducers in the runtime. 43 */ 44 45 #ifndef INCLUDED_REDUCER_IMPL_DOT_H 46 #define INCLUDED_REDUCER_IMPL_DOT_H 47 48 #include <cilk/common.h> 49 #include <internal/abi.h> 50 #include "rts-common.h" 51 52 __CILKRTS_BEGIN_EXTERN_C 53 54 /** 55 * Construct an empty reducer map from the memory pool associated with the 56 * given worker. This reducer map must be destroyed before the worker's 57 * associated global context is destroyed. 58 * 59 * @param w __cilkrts_worker the cilkred_map is being created for. 60 * 61 * @return Pointer to the initialized cilkred_map. 62 */ 63 COMMON_SYSDEP 64 cilkred_map *__cilkrts_make_reducer_map(__cilkrts_worker *w); 65 66 /** 67 * Destroy a reducer map. The map must have been allocated from the worker's 68 * global context and should have been allocated from the same worker. 69 * 70 * @param w __cilkrts_worker the cilkred_map was created for. 71 * @param h The cilkred_map to be deallocated. 72 */ 73 COMMON_SYSDEP 74 void __cilkrts_destroy_reducer_map(__cilkrts_worker *w, 75 cilkred_map *h); 76 77 /** 78 * Set the specified reducer map as the leftmost map if is_leftmost is true, 79 * otherwise, set it to not be the leftmost map. 80 * 81 * @param h The cilkred_map to be modified. 82 * @param is_leftmost true if the reducer map is leftmost. 83 */ 84 COMMON_SYSDEP 85 void __cilkrts_set_leftmost_reducer_map(cilkred_map *h, 86 int is_leftmost); 87 88 /** 89 * Merge reducer map RIGHT_MAP into LEFT_MAP and return the result of the 90 * merge. Both maps must be allocated from the global context associated 91 * with the specified worker. The returned reducer map must be destroyed 92 * before the worker's associated global context is destroyed. 93 * 94 * If two cilkred_maps are specified, one will be destroyed and the other 95 * one will be returned as the merged cilkred_map. 96 * 97 * When reducers can contain nested parallelism, execution can return 98 * on a different worker than when it started (but still using the 99 * same stack). 100 * 101 * Upon return, *w_ptr stores the pointer to the worker that execution 102 * returns on. 103 * 104 * @param w_ptr Pointer to the currently executing worker. 105 * @param left_map The left cilkred_map. 106 * @param right_map The right cilkred_map. 107 * 108 * @return pointer to merged cilkred_map. 109 */ 110 extern 111 cilkred_map *merge_reducer_maps(__cilkrts_worker **w_ptr, 112 cilkred_map *left_map, 113 cilkred_map *right_map); 114 115 /** 116 * Similar to merge_reducer_maps(), except that after merging 117 * RIGHT_MAP into LEFT_MAP, it repeatedly merges (*w_ptr)->reducer_map 118 * into LEFT_MAP. This procedure ensures that any new reducers 119 * created by the reductions themselves also get merged into LEFT_MAP. 120 */ 121 extern 122 cilkred_map *repeated_merge_reducer_maps(__cilkrts_worker **w_ptr, 123 cilkred_map *left_map, 124 cilkred_map *right_map); 125 126 __CILKRTS_END_EXTERN_C 127 128 #endif // ! defined(INCLUDED_REDUCER_IMPL_DOT_H) 129