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| author | Richard Sandiford <richard.sandiford@arm.com> | 2022-08-30 15:43:46 +0100 |
|---|---|---|
| committer | Richard Sandiford <richard.sandiford@arm.com> | 2022-08-30 15:43:46 +0100 |
| commit | 2bac880a19633b96608548b412739379df1c10dc (patch) | |
| tree | f3a194c64159c35b2cd9abdcf24cfd304cf2867c /gcc | |
| parent | 5551501e84dd51b569801c0e52b24f9e30124166 (diff) | |
| download | gcc-2bac880a19633b96608548b412739379df1c10dc.zip gcc-2bac880a19633b96608548b412739379df1c10dc.tar.gz gcc-2bac880a19633b96608548b412739379df1c10dc.tar.bz2 | |
Make graphds_scc pass the node order back to callers
As a side-effect, graphds_scc constructs a vector in which all
nodes in an SCC are listed consecutively. This can be useful
information, so that the patch adds an optional pass-back parameter
for it. The interface is similar to the one for graphds_dfs.
gcc/
* graphds.cc (graphds_scc): Add a pass-back parameter for the
final node order.
* graphds.h (graphds_scc): Update prototype accordingly.
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/graphds.cc | 13 | ||||
| -rw-r--r-- | gcc/graphds.h | 3 |
2 files changed, 12 insertions, 4 deletions
diff --git a/gcc/graphds.cc b/gcc/graphds.cc index 91a2ca5..2a108fd 100644 --- a/gcc/graphds.cc +++ b/gcc/graphds.cc @@ -281,7 +281,14 @@ graphds_dfs (struct graph *g, int *qs, int nq, vec<int> *qt, 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. If SKIP_EDGE_P is not NULL, it points to a callback function. - Edge E will be skipped if callback function returns true. + Edge E will be skipped if callback function returns true. If SCC_GROUPING + is not null, the nodes will be added to it in the following order: + + - If SCC A is a direct or indirect predecessor of SCC B in the SCC dag, + A's nodes come before B's nodes. + + - All of an SCC's nodes are listed consecutively, although the order + of the nodes within an SCC is not really meaningful. After running this function, v->component is the number of the strongly connected component for each vertex of G. Returns the number of the @@ -289,7 +296,7 @@ graphds_dfs (struct graph *g, int *qs, int nq, vec<int> *qt, int graphds_scc (struct graph *g, bitmap subgraph, - skip_edge_callback skip_edge_p) + skip_edge_callback skip_edge_p, vec<int> *scc_grouping) { int *queue = XNEWVEC (int, g->n_vertices); vec<int> postorder = vNULL; @@ -317,7 +324,7 @@ graphds_scc (struct graph *g, bitmap subgraph, for (i = 0; i < nq; i++) queue[i] = postorder[nq - i - 1]; - comp = graphds_dfs (g, queue, nq, NULL, true, subgraph, skip_edge_p); + comp = graphds_dfs (g, queue, nq, scc_grouping, true, subgraph, skip_edge_p); free (queue); postorder.release (); diff --git a/gcc/graphds.h b/gcc/graphds.h index c54d876..e0e4d80 100644 --- a/gcc/graphds.h +++ b/gcc/graphds.h @@ -58,7 +58,8 @@ void identify_vertices (struct graph *, int, int); typedef bool (*skip_edge_callback) (struct graph_edge *); int graphds_dfs (struct graph *, int *, int, vec<int> *, bool, bitmap, skip_edge_callback = NULL); -int graphds_scc (struct graph *, bitmap, skip_edge_callback = NULL); +int graphds_scc (struct graph *, bitmap, skip_edge_callback = NULL, + vec<int> * = NULL); void graphds_domtree (struct graph *, int, int *, int *, int *); typedef void (*graphds_edge_callback) (struct graph *, struct graph_edge *, void *); |