func findCallees(o *Oracle, site ssa.CallInstruction) ([]*ssa.Function, error) {
// Avoid running the pointer analysis for static calls.
if callee := site.Common().StaticCallee(); callee != nil {
switch callee.String() {
case "runtime.SetFinalizer", "(reflect.Value).Call":
// The PTA treats calls to these intrinsics as dynamic.
// TODO(adonovan): avoid reliance on PTA internals.
default:
return []*ssa.Function{callee}, nil // singleton
}
}
// Dynamic call: use pointer analysis.
o.ptaConfig.BuildCallGraph = true
callgraph := ptrAnalysis(o).CallGraph
// Find all call edges from the site.
calleesMap := make(map[*ssa.Function]bool)
var foundCGNode bool
for _, n := range callgraph.Nodes() {
if n.Func() == site.Parent() {
foundCGNode = true
for _, edge := range n.Edges() {
if edge.Site == site {
calleesMap[edge.Callee.Func()] = true
}
}
}
}
if !foundCGNode {
return nil, fmt.Errorf("this call site is unreachable in this analysis")
}
// Discard context, de-duplicate and sort.
funcs := make([]*ssa.Function, 0, len(calleesMap))
for f := range calleesMap {
funcs = append(funcs, f)
}
sort.Sort(byFuncPos(funcs))
return funcs, nil
}
