1#!/usr/bin/gvpr -f 2// Compute the forward partition of the chosen function 3// 4// Run with graph ... | return-paths | subg-fwd -a functionname 5// or graph ... | subg-fwd 6 7 8BEGIN { 9 // Find the immediate parent subgraph of this object 10 graph_t find_owner(obj_t o, graph_t g) 11 { 12 graph_t g1; 13 for (g1 = fstsubg(g); g1; g1 = nxtsubg(g1)) 14 if(isIn(g1,o)) return g1; 15 return NULL; 16 } 17} 18 19BEG_G { 20 graph_t sg = subg ($, sprintf("incoming-%s", ARGV[0])); 21 graph_t returns = graph("return-edges", ""); // Temporary graph to hold return edges 22 graph_t target, g, g2; 23 node_t n; 24 edge_t e; 25 int i; 26 27 $tvtype = TV_fwd; 28 29 // find the ep corresponding to ARG[0] 30 for (g = fstsubg($G); g; g = nxtsubg(g)) { 31 if(g.fun == ARGV[0]) { 32 n = node($,g.ep); 33 $tvroot = n; 34 n.style = "filled"; 35 target = g; 36 break; 37 } 38 } 39 if(!target) { 40 printf(2, "Function %s not found\n", ARGV[0]); 41 exit(1); 42 } 43} 44 45// Preserve external functions 46E [op == "extern"] { 47 subnode (sg, head); 48} 49 50// Move unused return edges into a separate graph so they don't get followed 51N [op == "ret"] { 52 for (e = fstout($); e; e = nxtout(e)) 53 if (e.op == "ret" && !isIn(sg, e.head)) { 54 clone(returns, e); 55 delete($G, e); 56 } 57} 58 59// Recover elided return edge for this target node 60N [op == "target" && indegree == 1] { 61 n = copy(returns, $); 62 e = fstin(n); // each target node can only have one return edge 63 e = edge(copy(sg, e.tail), $, "recovered"); // clone should work here, but doesn't 64 copyA(fstin(n), e); 65} 66 67// Copy relevant nodes 68N { 69 $tvroot = NULL; 70 71 g = find_owner($, $G); 72 if(g && g != sg) 73 subnode (copy(sg, g), $); 74} 75 76END_G { 77 induce(sg); 78 write(sg); 79} 80