GCC Middle and Back End API Reference

Functions  
void  dump_graph () 
struct graph *  new_graph () 
struct graph_edge *  add_edge () 
void  identify_vertices () 
static int  dfs_edge_src () 
static int  dfs_edge_dest () 
static struct graph_edge *  foll_in_subgraph () 
static struct graph_edge *  dfs_fst_edge () 
static struct graph_edge *  dfs_next_edge () 
int  graphds_dfs (struct graph *g, int *qs, int nq, vec< int > *qt, bool forward, bitmap subgraph) 
int  graphds_scc () 
void  for_each_edge () 
void  free_graph () 
static int  tree_nca () 
void  graphds_domtree (struct graph *g, int entry, int *parent, int *son, int *brother) 

read 
Adds an edge from F to T to graph G. The new edge is returned.
Referenced by add_edge(), create_rdg_edges_for_scalar(), and write_alias_graph_to_ascii_dot().

inlinestatic 
Helper function for graphds_dfs. Returns the destination vertex of E, in the direction given by FORWARD.
Referenced by foll_in_subgraph().

inlinestatic 
Helper function for graphds_dfs. Returns the source vertex of E, in the direction given by FORWARD.
References graph_edge::dest, and graph_edge::src.

staticread 
Helper function for graphds_dfs. Select the first edge from V in G, in the direction given by FORWARD, that belongs to SUBGRAPH.
References foll_in_subgraph(), graph_edge::pred_next, and graph_edge::succ_next.

staticread 
Helper function for graphds_dfs. Returns the next edge after E, in the graph direction given by FORWARD, that belongs to SUBGRAPH.
References comp, graph::n_vertices, stack, and tick.
void dump_graph  (  ) 
@verbatim
Graph representation and manipulation functions. Copyright (C) 20072013 Free Software Foundation, Inc.
This file is part of GCC.
GCC 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.
GCC 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.
You should have received a copy of the GNU General Public License along with GCC; see the file COPYING3. If not see http://www.gnu.org/licenses/.
Dumps graph G into F.
References vertex::component, graph_edge::dest, vertex::pred, graph_edge::pred_next, graph_edge::src, vertex::succ, graph_edge::succ_next, and graph::vertices.

staticread 
Helper function for graphds_dfs. Returns the first edge after E (including E), in the graph direction given by FORWARD, that belongs to SUBGRAPH.
References bitmap_bit_p(), dfs_edge_dest(), graph_edge::pred_next, and graph_edge::succ_next.
Referenced by dfs_fst_edge().
void free_graph  (  ) 
Releases the memory occupied by G.
Referenced by stmts_from_loop().
int graphds_dfs  (  struct graph *  g, 
int *  qs,  
int  nq,  
vec< int > *  qt,  
bool  forward,  
bitmap  subgraph  
) 
Runs dfs search over vertices of G, from NQ vertices in queue QS. The vertices in postorder are stored into QT. If FORWARD is false, backward dfs is run. If SUBGRAPH is not NULL, it specifies the subgraph of G to run DFS on. Returns the number of the components of the graph (number of the restarts of DFS).
References vertex::component, vertex::post, and graph::vertices.
void graphds_domtree  (  struct graph *  g, 
int  entry,  
int *  parent,  
int *  son,  
int *  brother  
) 
Determines the dominance tree of G (stored in the PARENT, SON and BROTHER arrays), where the entry node is ENTRY.
We use a slight modification of the standard iterative algorithm, as described in K. D. Cooper, T. J. Harvey and K. Kennedy: A Simple, Fast Dominance Algorithm sort vertices in reverse postorder foreach v dom(v) = everything dom(entry) = entry; while (anything changes) foreach v dom(v) = {v} union (intersection of dom(p) over all predecessors of v) The sets dom(v) are represented by the parent links in the current version of the dominance tree.
int graphds_scc  (  ) 
Determines the strongly connected components of G, using the algorithm of Tarjan  first determine the postorder dfs numbering in reversed graph, then run the dfs on the original graph in the order given by decreasing numbers assigned by the previous pass. If SUBGRAPH is not NULL, it specifies the subgraph of G whose strongly connected components we want to determine. After running this function, v>component is the number of the strongly connected component for each vertex of G. Returns the number of the sccs of G.
void identify_vertices  (  ) 
Moves all the edges incident with U to V.
References graph_edge::src, vertex::succ, and graph_edge::succ_next.
Referenced by prune_bbs_to_update_dominators().

read 
Creates a new graph with N_VERTICES vertices.

static 
Returns the nearest common ancestor of X and Y in tree whose parent links are given by PARENT. MARKS is the array used to mark the vertices of the tree, and MARK is the number currently used as a mark.
We climb with X and Y up the tree, marking the visited nodes. When we first arrive to a marked node, it is the common ancestor.
If we reached the root with one of the vertices, continue with the other one till we reach the marked part of the tree.