diff options
Diffstat (limited to 'vendor/golang.org/x/tools/go/callgraph/util.go')
-rw-r--r-- | vendor/golang.org/x/tools/go/callgraph/util.go | 181 |
1 files changed, 0 insertions, 181 deletions
diff --git a/vendor/golang.org/x/tools/go/callgraph/util.go b/vendor/golang.org/x/tools/go/callgraph/util.go deleted file mode 100644 index a8f8903..0000000 --- a/vendor/golang.org/x/tools/go/callgraph/util.go +++ /dev/null @@ -1,181 +0,0 @@ -// Copyright 2013 The Go Authors. All rights reserved. -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -package callgraph - -import "golang.org/x/tools/go/ssa" - -// This file provides various utilities over call graphs, such as -// visitation and path search. - -// CalleesOf returns a new set containing all direct callees of the -// caller node. -// -func CalleesOf(caller *Node) map[*Node]bool { - callees := make(map[*Node]bool) - for _, e := range caller.Out { - callees[e.Callee] = true - } - return callees -} - -// GraphVisitEdges visits all the edges in graph g in depth-first order. -// The edge function is called for each edge in postorder. If it -// returns non-nil, visitation stops and GraphVisitEdges returns that -// value. -// -func GraphVisitEdges(g *Graph, edge func(*Edge) error) error { - seen := make(map[*Node]bool) - var visit func(n *Node) error - visit = func(n *Node) error { - if !seen[n] { - seen[n] = true - for _, e := range n.Out { - if err := visit(e.Callee); err != nil { - return err - } - if err := edge(e); err != nil { - return err - } - } - } - return nil - } - for _, n := range g.Nodes { - if err := visit(n); err != nil { - return err - } - } - return nil -} - -// PathSearch finds an arbitrary path starting at node start and -// ending at some node for which isEnd() returns true. On success, -// PathSearch returns the path as an ordered list of edges; on -// failure, it returns nil. -// -func PathSearch(start *Node, isEnd func(*Node) bool) []*Edge { - stack := make([]*Edge, 0, 32) - seen := make(map[*Node]bool) - var search func(n *Node) []*Edge - search = func(n *Node) []*Edge { - if !seen[n] { - seen[n] = true - if isEnd(n) { - return stack - } - for _, e := range n.Out { - stack = append(stack, e) // push - if found := search(e.Callee); found != nil { - return found - } - stack = stack[:len(stack)-1] // pop - } - } - return nil - } - return search(start) -} - -// DeleteSyntheticNodes removes from call graph g all nodes for -// synthetic functions (except g.Root and package initializers), -// preserving the topology. In effect, calls to synthetic wrappers -// are "inlined". -// -func (g *Graph) DeleteSyntheticNodes() { - // Measurements on the standard library and go.tools show that - // resulting graph has ~15% fewer nodes and 4-8% fewer edges - // than the input. - // - // Inlining a wrapper of in-degree m, out-degree n adds m*n - // and removes m+n edges. Since most wrappers are monomorphic - // (n=1) this results in a slight reduction. Polymorphic - // wrappers (n>1), e.g. from embedding an interface value - // inside a struct to satisfy some interface, cause an - // increase in the graph, but they seem to be uncommon. - - // Hash all existing edges to avoid creating duplicates. - edges := make(map[Edge]bool) - for _, cgn := range g.Nodes { - for _, e := range cgn.Out { - edges[*e] = true - } - } - for fn, cgn := range g.Nodes { - if cgn == g.Root || fn.Synthetic == "" || isInit(cgn.Func) { - continue // keep - } - for _, eIn := range cgn.In { - for _, eOut := range cgn.Out { - newEdge := Edge{eIn.Caller, eIn.Site, eOut.Callee} - if edges[newEdge] { - continue // don't add duplicate - } - AddEdge(eIn.Caller, eIn.Site, eOut.Callee) - edges[newEdge] = true - } - } - g.DeleteNode(cgn) - } -} - -func isInit(fn *ssa.Function) bool { - return fn.Pkg != nil && fn.Pkg.Func("init") == fn -} - -// DeleteNode removes node n and its edges from the graph g. -// (NB: not efficient for batch deletion.) -func (g *Graph) DeleteNode(n *Node) { - n.deleteIns() - n.deleteOuts() - delete(g.Nodes, n.Func) -} - -// deleteIns deletes all incoming edges to n. -func (n *Node) deleteIns() { - for _, e := range n.In { - removeOutEdge(e) - } - n.In = nil -} - -// deleteOuts deletes all outgoing edges from n. -func (n *Node) deleteOuts() { - for _, e := range n.Out { - removeInEdge(e) - } - n.Out = nil -} - -// removeOutEdge removes edge.Caller's outgoing edge 'edge'. -func removeOutEdge(edge *Edge) { - caller := edge.Caller - n := len(caller.Out) - for i, e := range caller.Out { - if e == edge { - // Replace it with the final element and shrink the slice. - caller.Out[i] = caller.Out[n-1] - caller.Out[n-1] = nil // aid GC - caller.Out = caller.Out[:n-1] - return - } - } - panic("edge not found: " + edge.String()) -} - -// removeInEdge removes edge.Callee's incoming edge 'edge'. -func removeInEdge(edge *Edge) { - caller := edge.Callee - n := len(caller.In) - for i, e := range caller.In { - if e == edge { - // Replace it with the final element and shrink the slice. - caller.In[i] = caller.In[n-1] - caller.In[n-1] = nil // aid GC - caller.In = caller.In[:n-1] - return - } - } - panic("edge not found: " + edge.String()) -} |