| // 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 pointer |
| |
| // This file defines our implementation of the call.Graph API. |
| |
| import ( |
| "fmt" |
| "go/token" |
| |
| "code.google.com/p/go.tools/call" |
| "code.google.com/p/go.tools/ssa" |
| ) |
| |
| // cgraph implements call.Graph. |
| type cgraph struct { |
| root *cgnode |
| nodes []*cgnode |
| } |
| |
| func (g *cgraph) Nodes() []call.GraphNode { |
| nodes := make([]call.GraphNode, len(g.nodes)) |
| for i, node := range g.nodes { |
| nodes[i] = node |
| } |
| return nodes |
| } |
| |
| func (g *cgraph) Root() call.GraphNode { |
| return g.root |
| } |
| |
| // cgnode implements call.GraphNode. |
| type cgnode struct { |
| fn *ssa.Function |
| obj nodeid // start of this contour's object block |
| sites []*callsite // ordered list of callsites within this function |
| callersite *callsite // where called from, if known; nil for shared contours |
| } |
| |
| func (n *cgnode) Func() *ssa.Function { |
| return n.fn |
| } |
| |
| func (n *cgnode) Sites() []ssa.CallInstruction { |
| sites := make([]ssa.CallInstruction, len(n.sites)) |
| for i, site := range n.sites { |
| sites[i] = site.instr |
| } |
| return sites |
| } |
| |
| func (n *cgnode) Edges() []call.Edge { |
| var numEdges int |
| for _, site := range n.sites { |
| numEdges += len(site.callees) |
| } |
| edges := make([]call.Edge, 0, numEdges) |
| |
| for _, site := range n.sites { |
| for _, callee := range site.callees { |
| edges = append(edges, call.Edge{Caller: n, Site: site.instr, Callee: callee}) |
| } |
| } |
| return edges |
| } |
| |
| func (n *cgnode) String() string { |
| return fmt.Sprintf("cg%d:%s", n.obj, n.fn) |
| } |
| |
| // A callsite represents a single call site within a cgnode; |
| // it is implicitly context-sensitive. |
| // callsites never represent calls to built-ins; |
| // they are handled as intrinsics. |
| // |
| type callsite struct { |
| targets nodeid // pts(ยท) contains objects for dynamically called functions |
| instr ssa.CallInstruction // the call instruction; nil for synthetic/intrinsic |
| callees []*cgnode // unordered set of callees of this site |
| } |
| |
| func (c *callsite) String() string { |
| if c.instr != nil { |
| return c.instr.Common().Description() |
| } |
| return "synthetic function call" |
| } |
| |
| // pos returns the source position of this callsite, or token.NoPos if implicit. |
| func (c *callsite) pos() token.Pos { |
| if c.instr != nil { |
| return c.instr.Pos() |
| } |
| return token.NoPos |
| } |