Example #1
0
func TestStatic(t *testing.T) {
	conf := loader.Config{ParserMode: parser.ParseComments}
	f, err := conf.ParseFile("P.go", input)
	if err != nil {
		t.Fatal(err)
	}

	conf.CreateFromFiles("P", f)
	iprog, err := conf.Load()
	if err != nil {
		t.Fatal(err)
	}

	P := iprog.Created[0].Pkg

	prog := ssautil.CreateProgram(iprog, 0)
	prog.BuildAll()

	cg := static.CallGraph(prog)

	var edges []string
	callgraph.GraphVisitEdges(cg, func(e *callgraph.Edge) error {
		edges = append(edges, fmt.Sprintf("%s -> %s",
			e.Caller.Func.RelString(P),
			e.Callee.Func.RelString(P)))
		return nil
	})
	sort.Strings(edges)

	want := []string{
		"(*C).f -> (C).f",
		"f -> (C).f",
		"f -> f$1",
		"f -> g",
	}
	if !reflect.DeepEqual(edges, want) {
		t.Errorf("Got edges %v, want %v", edges, want)
	}
}
Example #2
0
func doCallgraph(ctxt *build.Context, algo, format string, tests bool, args []string) error {
	conf := loader.Config{
		Build:         ctxt,
		SourceImports: true,
	}

	if len(args) == 0 {
		fmt.Fprintln(os.Stderr, Usage)
		return nil
	}

	// Use the initial packages from the command line.
	args, err := conf.FromArgs(args, tests)
	if err != nil {
		return err
	}

	// Load, parse and type-check the whole program.
	iprog, err := conf.Load()
	if err != nil {
		return err
	}

	// Create and build SSA-form program representation.
	prog := ssa.Create(iprog, 0)
	prog.BuildAll()

	// -- call graph construction ------------------------------------------

	var cg *callgraph.Graph

	switch algo {
	case "static":
		cg = static.CallGraph(prog)

	case "cha":
		cg = cha.CallGraph(prog)

	case "pta":
		main, err := mainPackage(prog, tests)
		if err != nil {
			return err
		}
		config := &pointer.Config{
			Mains:          []*ssa.Package{main},
			BuildCallGraph: true,
		}
		ptares, err := pointer.Analyze(config)
		if err != nil {
			return err // internal error in pointer analysis
		}
		cg = ptares.CallGraph

	case "rta":
		main, err := mainPackage(prog, tests)
		if err != nil {
			return err
		}
		roots := []*ssa.Function{
			main.Func("init"),
			main.Func("main"),
		}
		rtares := rta.Analyze(roots, true)
		cg = rtares.CallGraph

		// NB: RTA gives us Reachable and RuntimeTypes too.

	default:
		return fmt.Errorf("unknown algorithm: %s", algo)
	}

	cg.DeleteSyntheticNodes()

	// -- output------------------------------------------------------------

	var before, after string

	// Pre-canned formats.
	switch format {
	case "digraph":
		format = `{{printf "%q %q" .Caller .Callee}}`

	case "graphviz":
		before = "digraph callgraph {\n"
		after = "}\n"
		format = `  {{printf "%q" .Caller}} -> {{printf "%q" .Callee}}"`
	}

	tmpl, err := template.New("-format").Parse(format)
	if err != nil {
		return fmt.Errorf("invalid -format template: %v", err)
	}

	// Allocate these once, outside the traversal.
	var buf bytes.Buffer
	data := Edge{fset: prog.Fset}

	fmt.Fprint(stdout, before)
	if err := callgraph.GraphVisitEdges(cg, func(edge *callgraph.Edge) error {
		data.position.Offset = -1
		data.edge = edge
		data.Caller = edge.Caller.Func
		data.Callee = edge.Callee.Func

		buf.Reset()
		if err := tmpl.Execute(&buf, &data); err != nil {
			return err
		}
		stdout.Write(buf.Bytes())
		if len := buf.Len(); len == 0 || buf.Bytes()[len-1] != '\n' {
			fmt.Fprintln(stdout)
		}
		return nil
	}); err != nil {
		return err
	}
	fmt.Fprint(stdout, after)
	return nil
}
Example #3
0
// Callstack displays an arbitrary path from a root of the callgraph
// to the function at the current position.
//
// The information may be misleading in a context-insensitive
// analysis. e.g. the call path X->Y->Z might be infeasible if Y never
// calls Z when it is called from X.  TODO(adonovan): think about UI.
//
// TODO(adonovan): permit user to specify a starting point other than
// the analysis root.
//
func callstack(q *Query) error {
	fset := token.NewFileSet()
	lconf := loader.Config{Fset: fset, Build: q.Build}

	if err := setPTAScope(&lconf, q.Scope); err != nil {
		return err
	}

	// Load/parse/type-check the program.
	lprog, err := loadWithSoftErrors(&lconf)
	if err != nil {
		return err
	}

	qpos, err := parseQueryPos(lprog, q.Pos, false)
	if err != nil {
		return err
	}

	prog := ssautil.CreateProgram(lprog, 0)

	ptaConfig, err := setupPTA(prog, lprog, q.PTALog, q.Reflection)
	if err != nil {
		return err
	}

	pkg := prog.Package(qpos.info.Pkg)
	if pkg == nil {
		return fmt.Errorf("no SSA package")
	}

	if !ssa.HasEnclosingFunction(pkg, qpos.path) {
		return fmt.Errorf("this position is not inside a function")
	}

	// Defer SSA construction till after errors are reported.
	prog.Build()

	target := ssa.EnclosingFunction(pkg, qpos.path)
	if target == nil {
		return fmt.Errorf("no SSA function built for this location (dead code?)")
	}

	var callpath []*callgraph.Edge
	isEnd := func(n *callgraph.Node) bool { return n.Func == target }

	// First, build a callgraph containing only static call edges,
	// and search for an arbitrary path from a root to the target function.
	// This is quick, and the user wants a static path if one exists.
	cg := static.CallGraph(prog)
	cg.DeleteSyntheticNodes()
	for _, ep := range entryPoints(ptaConfig.Mains) {
		callpath = callgraph.PathSearch(cg.CreateNode(ep), isEnd)
		if callpath != nil {
			break
		}
	}

	// No fully static path found.
	// Run the pointer analysis and build a complete call graph.
	if callpath == nil {
		ptaConfig.BuildCallGraph = true
		cg := ptrAnalysis(ptaConfig).CallGraph
		cg.DeleteSyntheticNodes()
		callpath = callgraph.PathSearch(cg.Root, isEnd)
		if callpath != nil {
			callpath = callpath[1:] // remove synthetic edge from <root>
		}
	}

	q.Output(fset, &callstackResult{
		qpos:     qpos,
		target:   target,
		callpath: callpath,
	})
	return nil
}
Example #4
0
func doCallgraph(ctxt *build.Context, algo, format string, tests bool, args []string) error {
	conf := loader.Config{Build: ctxt}

	if len(args) == 0 {
		fmt.Fprintln(os.Stderr, Usage)
		return nil
	}

	if *fileFlag == "" || *lineFlag == -1 {
		fmt.Fprintln(os.Stderr, "Need input file and line")
		return nil
	}

	// Use the initial packages from the command line.
	args, err := conf.FromArgs(args, tests)
	if err != nil {
		return err
	}

	// Load, parse and type-check the whole program.
	iprog, err := conf.Load()
	if err != nil {
		return err
	}

	// Create and build SSA-form program representation.
	prog := ssautil.CreateProgram(iprog, 0)
	prog.Build()

	// -- call graph construction ------------------------------------------

	var cg *callgraph.Graph

	switch algo {
	case "static":
		cg = static.CallGraph(prog)

	case "cha":
		cg = cha.CallGraph(prog)

	case "pta":
		// Set up points-to analysis log file.
		var ptalog io.Writer
		if *ptalogFlag != "" {
			if f, err := os.Create(*ptalogFlag); err != nil {
				log.Fatalf("Failed to create PTA log file: %s", err)
			} else {
				buf := bufio.NewWriter(f)
				ptalog = buf
				defer func() {
					if err := buf.Flush(); err != nil {
						log.Printf("flush: %s", err)
					}
					if err := f.Close(); err != nil {
						log.Printf("close: %s", err)
					}
				}()
			}
		}

		main, err := mainPackage(prog, tests)
		if err != nil {
			return err
		}
		config := &pointer.Config{
			Mains:          []*ssa.Package{main},
			BuildCallGraph: true,
			Log:            ptalog,
		}
		ptares, err := pointer.Analyze(config)
		if err != nil {
			return err // internal error in pointer analysis
		}
		cg = ptares.CallGraph

	case "rta":
		main, err := mainPackage(prog, tests)
		if err != nil {
			return err
		}
		roots := []*ssa.Function{
			main.Func("init"),
			main.Func("main"),
		}
		rtares := rta.Analyze(roots, true)
		cg = rtares.CallGraph

		// NB: RTA gives us Reachable and RuntimeTypes too.

	default:
		return fmt.Errorf("unknown algorithm: %s", algo)
	}

	cg.DeleteSyntheticNodes()

	// -- output------------------------------------------------------------

	file := *fileFlag
	line := *lineFlag
	depth := *depthFlag

	node := findFunction(cg, file, line)
	if node == nil {
		panic("function not found")
	}

	ins, before := ChainBefore(node)
	after, outs := ChainAfter(node)
	chain := append(before, after[1:]...)

	sort.Sort(SortNodes(ins))
	for _, n := range ins {
		_, ch := ChainBefore(n)
		fmt.Printf("(%d) %s\n", impact(ch[0]), chainToString(ch))
	}
	fmt.Println()
	fmt.Println(chainToString(chain))
	fmt.Println()

	sort.Sort(SortNodes(outs))
	for _, n := range outs {
		if impact(n) > minImpact {
			continue
		}
		printFanout(depth, "", n)
	}

	return nil
}