1 /* DDG - Data Dependence Graph - interface. 2 Copyright (C) 2004, 2005, 2006, 2007, 2008 3 Free Software Foundation, Inc. 4 Contributed by Ayal Zaks and Mustafa Hagog <zaks,mustafa@il.ibm.com> 5 6 This file is part of GCC. 7 8 GCC is free software; you can redistribute it and/or modify it under 9 the terms of the GNU General Public License as published by the Free 10 Software Foundation; either version 3, or (at your option) any later 11 version. 12 13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY 14 WARRANTY; without even the implied warranty of MERCHANTABILITY or 15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 16 for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with GCC; see the file COPYING3. If not see 20 <http://www.gnu.org/licenses/>. */ 21 22 #ifndef GCC_DDG_H 23 #define GCC_DDG_H 24 25 /* For sbitmap. */ 26 #include "sbitmap.h" 27 /* For basic_block. */ 28 #include "basic-block.h" 29 #include "df.h" 30 31 typedef struct ddg_node *ddg_node_ptr; 32 typedef struct ddg_edge *ddg_edge_ptr; 33 typedef struct ddg *ddg_ptr; 34 typedef struct ddg_scc *ddg_scc_ptr; 35 typedef struct ddg_all_sccs *ddg_all_sccs_ptr; 36 37 typedef enum {TRUE_DEP, OUTPUT_DEP, ANTI_DEP} dep_type; 38 typedef enum {REG_OR_MEM_DEP, REG_DEP, MEM_DEP, REG_AND_MEM_DEP} 39 dep_data_type; 40 41 /* The following two macros enables direct access to the successors and 42 predecessors bitmaps held in each ddg_node. Do not make changes to 43 these bitmaps, unless you want to change the DDG. */ 44 #define NODE_SUCCESSORS(x) ((x)->successors) 45 #define NODE_PREDECESSORS(x) ((x)->predecessors) 46 47 /* A structure that represents a node in the DDG. */ 48 struct ddg_node 49 { 50 /* Each node has a unique CUID index. These indices increase monotonically 51 (according to the order of the corresponding INSN in the BB), starting 52 from 0 with no gaps. */ 53 int cuid; 54 55 /* The insn represented by the node. */ 56 rtx insn; 57 58 /* A note preceding INSN (or INSN itself), such that all insns linked 59 from FIRST_NOTE until INSN (inclusive of both) are moved together 60 when reordering the insns. This takes care of notes that should 61 continue to precede INSN. */ 62 rtx first_note; 63 64 /* Incoming and outgoing dependency edges. */ 65 ddg_edge_ptr in; 66 ddg_edge_ptr out; 67 68 /* Each bit corresponds to a ddg_node according to its cuid, and is 69 set iff the node is a successor/predecessor of "this" node. */ 70 sbitmap successors; 71 sbitmap predecessors; 72 73 /* For general use by algorithms manipulating the ddg. */ 74 union { 75 int count; 76 void *info; 77 } aux; 78 }; 79 80 /* A structure that represents an edge in the DDG. */ 81 struct ddg_edge 82 { 83 /* The source and destination nodes of the dependency edge. */ 84 ddg_node_ptr src; 85 ddg_node_ptr dest; 86 87 /* TRUE, OUTPUT or ANTI dependency. */ 88 dep_type type; 89 90 /* REG or MEM dependency. */ 91 dep_data_type data_type; 92 93 /* Latency of the dependency. */ 94 int latency; 95 96 /* The distance: number of loop iterations the dependency crosses. */ 97 int distance; 98 99 /* The following two fields are used to form a linked list of the in/out 100 going edges to/from each node. */ 101 ddg_edge_ptr next_in; 102 ddg_edge_ptr next_out; 103 104 /* For general use by algorithms manipulating the ddg. */ 105 union { 106 int count; 107 void *info; 108 } aux; 109 }; 110 111 /* This structure holds the Data Dependence Graph for a basic block. */ 112 struct ddg 113 { 114 /* The basic block for which this DDG is built. */ 115 basic_block bb; 116 117 /* Number of instructions in the basic block. */ 118 int num_nodes; 119 120 /* Number of load/store instructions in the BB - statistics. */ 121 int num_loads; 122 int num_stores; 123 124 /* Number of debug instructions in the BB. */ 125 int num_debug; 126 127 /* This array holds the nodes in the graph; it is indexed by the node 128 cuid, which follows the order of the instructions in the BB. */ 129 ddg_node_ptr nodes; 130 131 /* The branch closing the loop. */ 132 ddg_node_ptr closing_branch; 133 134 /* Build dependence edges for closing_branch, when set. In certain cases, 135 the closing branch can be dealt with separately from the insns of the 136 loop, and then no such deps are needed. */ 137 int closing_branch_deps; 138 139 /* Array and number of backarcs (edges with distance > 0) in the DDG. */ 140 int num_backarcs; 141 ddg_edge_ptr *backarcs; 142 }; 143 144 145 /* Holds information on an SCC (Strongly Connected Component) of the DDG. */ 146 struct ddg_scc 147 { 148 /* A bitmap that represents the nodes of the DDG that are in the SCC. */ 149 sbitmap nodes; 150 151 /* Array and number of backarcs (edges with distance > 0) in the SCC. */ 152 ddg_edge_ptr *backarcs; 153 int num_backarcs; 154 155 /* The maximum of (total_latency/total_distance) over all cycles in SCC. */ 156 int recurrence_length; 157 }; 158 159 /* This structure holds the SCCs of the DDG. */ 160 struct ddg_all_sccs 161 { 162 /* Array that holds the SCCs in the DDG, and their number. */ 163 ddg_scc_ptr *sccs; 164 int num_sccs; 165 166 ddg_ptr ddg; 167 }; 168 169 170 ddg_ptr create_ddg (basic_block, int closing_branch_deps); 171 void free_ddg (ddg_ptr); 172 173 void print_ddg (FILE *, ddg_ptr); 174 void vcg_print_ddg (FILE *, ddg_ptr); 175 void print_ddg_edge (FILE *, ddg_edge_ptr); 176 void print_sccs (FILE *, ddg_all_sccs_ptr, ddg_ptr); 177 178 ddg_node_ptr get_node_of_insn (ddg_ptr, rtx); 179 180 void find_successors (sbitmap result, ddg_ptr, sbitmap); 181 void find_predecessors (sbitmap result, ddg_ptr, sbitmap); 182 183 ddg_all_sccs_ptr create_ddg_all_sccs (ddg_ptr); 184 void free_ddg_all_sccs (ddg_all_sccs_ptr); 185 186 int find_nodes_on_paths (sbitmap result, ddg_ptr, sbitmap from, sbitmap to); 187 int longest_simple_path (ddg_ptr, int from, int to, sbitmap via); 188 189 bool autoinc_var_is_used_p (rtx, rtx); 190 191 #endif /* GCC_DDG_H */ 192