Golang ssa.Create函数代码示例

func TestSwitches(t *testing.T) {
	conf := loader.Config{ParserMode: parser.ParseComments}
	f, err := conf.ParseFile("testdata/switches.go", nil)
	if err != nil {
		t.Error(err)
		return
	}

	conf.CreateFromFiles("main", f)
	iprog, err := conf.Load()
	if err != nil {
		t.Error(err)
		return
	}

	prog := ssa.Create(iprog, 0)
	mainPkg := prog.Package(iprog.Created[0].Pkg)
	mainPkg.Build()

	for _, mem := range mainPkg.Members {
		if fn, ok := mem.(*ssa.Function); ok {
			if fn.Synthetic != "" {
				continue // e.g. init()
			}
			// Each (multi-line) "switch" comment within
			// this function must match the printed form
			// of a ConstSwitch.
			var wantSwitches []string
			for _, c := range f.Comments {
				if fn.Syntax().Pos() <= c.Pos() && c.Pos() < fn.Syntax().End() {
					text := strings.TrimSpace(c.Text())
					if strings.HasPrefix(text, "switch ") {
						wantSwitches = append(wantSwitches, text)
					}
				}
			}

			switches := ssautil.Switches(fn)
			if len(switches) != len(wantSwitches) {
				t.Errorf("in %s, found %d switches, want %d", fn, len(switches), len(wantSwitches))
			}
			for i, sw := range switches {
				got := sw.String()
				if i >= len(wantSwitches) {
					continue
				}
				want := wantSwitches[i]
				if got != want {
					t.Errorf("in %s, found switch %d: got <<%s>>, want <<%s>>", fn, i, got, want)
				}
			}
		}
	}
}

func create(t *testing.T, content string) []*ssa.Package {
	var conf loader.Config
	f, err := conf.ParseFile("foo_test.go", content)
	if err != nil {
		t.Fatal(err)
	}
	conf.CreateFromFiles("foo", f)

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

	// We needn't call Build.
	return ssa.Create(iprog, ssa.SanityCheckFunctions).AllPackages()
}

func newOracle(iprog *loader.Program, ptalog io.Writer, needs int, reflection bool) (*Oracle, error) {
	o := &Oracle{fset: iprog.Fset}

	// Retain type info for all ASTs in the program.
	if needs&needRetainTypeInfo != 0 {
		o.typeInfo = iprog.AllPackages
	}

	// Create SSA package for the initial packages and their dependencies.
	if needs&needSSA != 0 {
		var mode ssa.BuilderMode
		if needs&needSSADebug != 0 {
			mode |= ssa.GlobalDebug
		}
		prog := ssa.Create(iprog, mode)

		// For each initial package (specified on the command line),
		// if it has a main function, analyze that,
		// otherwise analyze its tests, if any.
		var testPkgs, mains []*ssa.Package
		for _, info := range iprog.InitialPackages() {
			initialPkg := prog.Package(info.Pkg)

			// Add package to the pointer analysis scope.
			if initialPkg.Func("main") != nil {
				mains = append(mains, initialPkg)
			} else {
				testPkgs = append(testPkgs, initialPkg)
			}
		}
		if testPkgs != nil {
			if p := prog.CreateTestMainPackage(testPkgs...); p != nil {
				mains = append(mains, p)
			}
		}
		if mains == nil {
			return nil, fmt.Errorf("analysis scope has no main and no tests")
		}
		o.ptaConfig.Log = ptalog
		o.ptaConfig.Reflection = reflection
		o.ptaConfig.Mains = mains

		o.prog = prog
	}

	return o, nil
}

// CreateTestMainPackage should return nil if there were no tests.
func TestNullTestmainPackage(t *testing.T) {
	var conf loader.Config
	if err := conf.CreateFromFilenames("", "testdata/b_test.go"); err != nil {
		t.Fatalf("ParseFile failed: %s", err)
	}
	iprog, err := conf.Load()
	if err != nil {
		t.Fatalf("CreatePackages failed: %s", err)
	}
	prog := ssa.Create(iprog, ssa.SanityCheckFunctions)
	mainPkg := prog.Package(iprog.Created[0].Pkg)
	if mainPkg.Func("main") != nil {
		t.Fatalf("unexpected main function")
	}
	if prog.CreateTestMainPackage(mainPkg) != nil {
		t.Fatalf("CreateTestMainPackage returned non-nil")
	}
}

// TestTypesWithMethodSets tests that Package.TypesWithMethodSets includes all necessary types.
func TestTypesWithMethodSets(t *testing.T) {
	tests := []struct {
		input string
		want  []string
	}{
		// An exported package-level type is needed.
		{`package A; type T struct{}; func (T) f() {}`,
			[]string{"*p.T", "p.T"},
		},
		// An unexported package-level type is not needed.
		{`package B; type t struct{}; func (t) f() {}`,
			nil,
		},
		// Subcomponents of type of exported package-level var are needed.
		{`package C; import "bytes"; var V struct {*bytes.Buffer}`,
			[]string{"*struct{*bytes.Buffer}", "struct{*bytes.Buffer}"},
		},
		// Subcomponents of type of unexported package-level var are not needed.
		{`package D; import "bytes"; var v struct {*bytes.Buffer}`,
			nil,
		},
		// Subcomponents of type of exported package-level function are needed.
		{`package E; import "bytes"; func F(struct {*bytes.Buffer}) {}`,
			[]string{"struct{*bytes.Buffer}"},
		},
		// Subcomponents of type of unexported package-level function are not needed.
		{`package F; import "bytes"; func f(struct {*bytes.Buffer}) {}`,
			nil,
		},
		// Subcomponents of type of exported method of uninstantiated unexported type are not needed.
		{`package G; import "bytes"; type x struct{}; func (x) G(struct {*bytes.Buffer}) {}; var v x`,
			nil,
		},
		// ...unless used by MakeInterface.
		{`package G2; import "bytes"; type x struct{}; func (x) G(struct {*bytes.Buffer}) {}; var v interface{} = x{}`,
			[]string{"*p.x", "p.x", "struct{*bytes.Buffer}"},
		},
		// Subcomponents of type of unexported method are not needed.
		{`package I; import "bytes"; type X struct{}; func (X) G(struct {*bytes.Buffer}) {}`,
			[]string{"*p.X", "p.X", "struct{*bytes.Buffer}"},
		},
		// Local types aren't needed.
		{`package J; import "bytes"; func f() { type T struct {*bytes.Buffer}; var t T; _ = t }`,
			nil,
		},
		// ...unless used by MakeInterface.
		{`package K; import "bytes"; func f() { type T struct {*bytes.Buffer}; _ = interface{}(T{}) }`,
			[]string{"*p.T", "p.T"},
		},
		// Types used as operand of MakeInterface are needed.
		{`package L; import "bytes"; func f() { _ = interface{}(struct{*bytes.Buffer}{}) }`,
			[]string{"struct{*bytes.Buffer}"},
		},
		// MakeInterface is optimized away when storing to a blank.
		{`package M; import "bytes"; var _ interface{} = struct{*bytes.Buffer}{}`,
			nil,
		},
	}
	for _, test := range tests {
		// Create a single-file main package.
		var conf loader.Config
		f, err := conf.ParseFile("<input>", test.input, 0)
		if err != nil {
			t.Errorf("test %q: %s", test.input[:15], err)
			continue
		}
		conf.CreateFromFiles("p", f)

		iprog, err := conf.Load()
		if err != nil {
			t.Errorf("test 'package %s': Load: %s", f.Name.Name, err)
			continue
		}
		prog := ssa.Create(iprog, ssa.SanityCheckFunctions)
		mainPkg := prog.Package(iprog.Created[0].Pkg)
		prog.BuildAll()

		var typstrs []string
		for _, T := range mainPkg.TypesWithMethodSets() {
			typstrs = append(typstrs, T.String())
		}
		sort.Strings(typstrs)

		if !reflect.DeepEqual(typstrs, test.want) {
			t.Errorf("test 'package %s': got %q, want %q", f.Name.Name, typstrs, test.want)
		}
	}
}

func TestObjValueLookup(t *testing.T) {
	conf := loader.Config{ParserMode: parser.ParseComments}
	f, err := conf.ParseFile("testdata/objlookup.go", nil)
	if err != nil {
		t.Error(err)
		return
	}
	conf.CreateFromFiles("main", f)

	// Maps each var Ident (represented "name:linenum") to the
	// kind of ssa.Value we expect (represented "Constant", "&Alloc").
	expectations := make(map[string]string)

	// Find all annotations of form x::BinOp, &y::Alloc, etc.
	re := regexp.MustCompile(`(\b|&)?(\w*)::(\w*)\b`)
	for _, c := range f.Comments {
		text := c.Text()
		pos := conf.Fset.Position(c.Pos())
		for _, m := range re.FindAllStringSubmatch(text, -1) {
			key := fmt.Sprintf("%s:%d", m[2], pos.Line)
			value := m[1] + m[3]
			expectations[key] = value
		}
	}

	iprog, err := conf.Load()
	if err != nil {
		t.Error(err)
		return
	}

	prog := ssa.Create(iprog, 0 /*|ssa.LogFunctions*/)
	mainInfo := iprog.Created[0]
	mainPkg := prog.Package(mainInfo.Pkg)
	mainPkg.SetDebugMode(true)
	mainPkg.Build()

	var varIds []*ast.Ident
	var varObjs []*types.Var
	for id, obj := range mainInfo.Defs {
		// Check invariants for func and const objects.
		switch obj := obj.(type) {
		case *types.Func:
			checkFuncValue(t, prog, obj)

		case *types.Const:
			checkConstValue(t, prog, obj)

		case *types.Var:
			if id.Name == "_" {
				continue
			}
			varIds = append(varIds, id)
			varObjs = append(varObjs, obj)
		}
	}
	for id, obj := range mainInfo.Uses {
		if obj, ok := obj.(*types.Var); ok {
			varIds = append(varIds, id)
			varObjs = append(varObjs, obj)
		}
	}

	// Check invariants for var objects.
	// The result varies based on the specific Ident.
	for i, id := range varIds {
		obj := varObjs[i]
		ref, _ := astutil.PathEnclosingInterval(f, id.Pos(), id.Pos())
		pos := prog.Fset.Position(id.Pos())
		exp := expectations[fmt.Sprintf("%s:%d", id.Name, pos.Line)]
		if exp == "" {
			t.Errorf("%s: no expectation for var ident %s ", pos, id.Name)
			continue
		}
		wantAddr := false
		if exp[0] == '&' {
			wantAddr = true
			exp = exp[1:]
		}
		checkVarValue(t, prog, mainPkg, ref, obj, exp, wantAddr)
	}
}

// Ensure that, in debug mode, we can determine the ssa.Value
// corresponding to every ast.Expr.
func TestValueForExpr(t *testing.T) {
	conf := loader.Config{ParserMode: parser.ParseComments}
	f, err := conf.ParseFile("testdata/valueforexpr.go", nil)
	if err != nil {
		t.Error(err)
		return
	}
	conf.CreateFromFiles("main", f)

	iprog, err := conf.Load()
	if err != nil {
		t.Error(err)
		return
	}

	mainInfo := iprog.Created[0]

	prog := ssa.Create(iprog, 0)
	mainPkg := prog.Package(mainInfo.Pkg)
	mainPkg.SetDebugMode(true)
	mainPkg.Build()

	if false {
		// debugging
		for _, mem := range mainPkg.Members {
			if fn, ok := mem.(*ssa.Function); ok {
				fn.WriteTo(os.Stderr)
			}
		}
	}

	// Find the actual AST node for each canonical position.
	parenExprByPos := make(map[token.Pos]*ast.ParenExpr)
	ast.Inspect(f, func(n ast.Node) bool {
		if n != nil {
			if e, ok := n.(*ast.ParenExpr); ok {
				parenExprByPos[e.Pos()] = e
			}
		}
		return true
	})

	// Find all annotations of form /*@kind*/.
	for _, c := range f.Comments {
		text := strings.TrimSpace(c.Text())
		if text == "" || text[0] != '@' {
			continue
		}
		text = text[1:]
		pos := c.End() + 1
		position := prog.Fset.Position(pos)
		var e ast.Expr
		if target := parenExprByPos[pos]; target == nil {
			t.Errorf("%s: annotation doesn't precede ParenExpr: %q", position, text)
			continue
		} else {
			e = target.X
		}

		path, _ := astutil.PathEnclosingInterval(f, pos, pos)
		if path == nil {
			t.Errorf("%s: can't find AST path from root to comment: %s", position, text)
			continue
		}

		fn := ssa.EnclosingFunction(mainPkg, path)
		if fn == nil {
			t.Errorf("%s: can't find enclosing function", position)
			continue
		}

		v, gotAddr := fn.ValueForExpr(e) // (may be nil)
		got := strings.TrimPrefix(fmt.Sprintf("%T", v), "*ssa.")
		if want := text; got != want {
			t.Errorf("%s: got value %q, want %q", position, got, want)
		}
		if v != nil {
			T := v.Type()
			if gotAddr {
				T = T.Underlying().(*types.Pointer).Elem() // deref
			}
			if !types.Identical(T, mainInfo.TypeOf(e)) {
				t.Errorf("%s: got type %s, want %s", position, mainInfo.TypeOf(e), T)
			}
		}
	}
}

func doOneInput(input, filename string) bool {
	conf := loader.Config{SourceImports: true}

	// Parsing.
	f, err := conf.ParseFile(filename, input)
	if err != nil {
		fmt.Println(err)
		return false
	}

	// Create single-file main package and import its dependencies.
	conf.CreateFromFiles("main", f)
	iprog, err := conf.Load()
	if err != nil {
		fmt.Println(err)
		return false
	}
	mainPkgInfo := iprog.Created[0].Pkg

	// SSA creation + building.
	prog := ssa.Create(iprog, ssa.SanityCheckFunctions)
	prog.BuildAll()

	mainpkg := prog.Package(mainPkgInfo)
	ptrmain := mainpkg // main package for the pointer analysis
	if mainpkg.Func("main") == nil {
		// No main function; assume it's a test.
		ptrmain = prog.CreateTestMainPackage(mainpkg)
	}

	// Find all calls to the built-in print(x).  Analytically,
	// print is a no-op, but it's a convenient hook for testing
	// the PTS of an expression, so our tests use it.
	probes := make(map[*ssa.CallCommon]bool)
	for fn := range ssautil.AllFunctions(prog) {
		if fn.Pkg == mainpkg {
			for _, b := range fn.Blocks {
				for _, instr := range b.Instrs {
					if instr, ok := instr.(ssa.CallInstruction); ok {
						if b, ok := instr.Common().Value.(*ssa.Builtin); ok && b.Name() == "print" {
							probes[instr.Common()] = true
						}
					}
				}
			}
		}
	}

	ok := true

	lineMapping := make(map[string]string) // maps "file:line" to @line tag

	// Parse expectations in this input.
	var exps []*expectation
	re := regexp.MustCompile("// *@([a-z]*) *(.*)$")
	lines := strings.Split(input, "\n")
	for linenum, line := range lines {
		linenum++ // make it 1-based
		if matches := re.FindAllStringSubmatch(line, -1); matches != nil {
			match := matches[0]
			kind, rest := match[1], match[2]
			e := &expectation{kind: kind, filename: filename, linenum: linenum}

			if kind == "line" {
				if rest == "" {
					ok = false
					e.errorf("@%s expectation requires identifier", kind)
				} else {
					lineMapping[fmt.Sprintf("%s:%d", filename, linenum)] = rest
				}
				continue
			}

			if e.needsProbe() && !strings.Contains(line, "print(") {
				ok = false
				e.errorf("@%s expectation must follow call to print(x)", kind)
				continue
			}

			switch kind {
			case "pointsto":
				e.args = split(rest, "|")

			case "types":
				for _, typstr := range split(rest, "|") {
					var t types.Type = types.Typ[types.Invalid] // means "..."
					if typstr != "..." {
						texpr, err := parser.ParseExpr(typstr)
						if err != nil {
							ok = false
							// Don't print err since its location is bad.
							e.errorf("'%s' is not a valid type", typstr)
							continue
						}
						mainFileScope := mainpkg.Object.Scope().Child(0)
						t, _, err = types.EvalNode(prog.Fset, texpr, mainpkg.Object, mainFileScope)
						if err != nil {
							ok = false
							// Don't print err since its location is bad.
							e.errorf("'%s' is not a valid type: %s", typstr, err)
//.........这里部分代码省略.........

func doTestable(args []string) error {

	conf := loader.Config{
		Build:         &build.Default,
		SourceImports: true,
	}

	// TODO(adonovan): make go/types choose its default Sizes from
	// build.Default or a specified *build.Context.
	var wordSize int64 = 8
	switch conf.Build.GOARCH {
	case "386", "arm":
		wordSize = 4
	}

	wordSize = 4 // TARDIS Go addition to force default int size to 32 bits
	//conf.Build.GOARCH = "tardisgo" // TARDIS Go addition to ensure no architecure-specific code will compile
	//conf.Build.GOOS = "tardisgo"   // TARDIS Go addition to ensure no OS-specific code will compile

	conf.TypeChecker.Sizes = &types.StdSizes{
		MaxAlign: 8,
		WordSize: wordSize,
	}

	var mode ssa.BuilderMode
	for _, c := range *buildFlag {
		switch c {
		case 'D':
			mode |= ssa.GlobalDebug
		case 'P':
			mode |= ssa.LogPackages | ssa.BuildSerially
		case 'F':
			mode |= ssa.LogFunctions | ssa.BuildSerially
		case 'S':
			mode |= ssa.LogSource | ssa.BuildSerially
		case 'C':
			mode |= ssa.SanityCheckFunctions
		case 'N':
			mode |= ssa.NaiveForm
		case 'G':
			conf.SourceImports = false
		case 'L':
			mode |= ssa.BuildSerially
		default:
			log.Fatalf("Unknown -build option: '%c'.", c)
		}
	}

	var interpMode interp.Mode
	for _, c := range *interpFlag {
		switch c {
		case 'T':
			interpMode |= interp.EnableTracing
		case 'R':
			interpMode |= interp.DisableRecover
		default:
			log.Fatalf("Unknown -interp option: '%c'.", c)
		}
	}

	if len(args) == 0 {
		//fmt.Fprint(os.Stderr, usage)
		return fmt.Errorf("%v", usage)
	}

	// Profiling support.
	if *cpuprofile != "" {
		f, err := os.Create(*cpuprofile)
		if err != nil {
			return err
		}
		pprof.StartCPUProfile(f)
		defer pprof.StopCPUProfile()
	}

	// TARDIS Go TEST
	// Really need to find a way to replace entire packages, this experiment did not work...
	/*
		conf.Fset = token.NewFileSet()
		f, err := parser.ParseFile(conf.Fset, conf.Build.GOPATH+"/src/github.com/tardisgo/tardisgo/golibruntime/runtime/runtime.go", nil, 0)
		if err != nil {
			fmt.Println(err)
			return err
		}
		conf.CreateFromFiles("", f)
		fmt.Printf("DEBUG %s %s\n", f.Name.Name, "") //, f.Name.Obj.Name)
	*/
	// end TARDIS Go TEST

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

	// The interpreter needs the runtime package.
	if *runFlag {
		conf.Import("runtime")
		conf.Import("github.com/tardisgo/tardisgo/golibruntime/runtime") // This required for TARDIS go to run runtime
	}
//.........这里部分代码省略.........

// Run runs program analysis and computes the resulting markup,
// populating *result in a thread-safe manner, first with type
// information then later with pointer analysis information if
// enabled by the pta flag.
//
func Run(pta bool, result *Result) {
	conf := loader.Config{
		SourceImports:   true,
		AllowTypeErrors: true,
	}

	errors := make(map[token.Pos][]string)
	conf.TypeChecker.Error = func(e error) {
		err := e.(types.Error)
		errors[err.Pos] = append(errors[err.Pos], err.Msg)
	}

	var roots, args []string // roots[i] ends with os.PathSeparator

	// Enumerate packages in $GOROOT.
	root := filepath.Join(runtime.GOROOT(), "src", "pkg") + string(os.PathSeparator)
	roots = append(roots, root)
	args = allPackages(root)
	log.Printf("GOROOT=%s: %s\n", root, args)

	// Enumerate packages in $GOPATH.
	for i, dir := range filepath.SplitList(build.Default.GOPATH) {
		root := filepath.Join(dir, "src") + string(os.PathSeparator)
		roots = append(roots, root)
		pkgs := allPackages(root)
		log.Printf("GOPATH[%d]=%s: %s\n", i, root, pkgs)
		args = append(args, pkgs...)
	}

	// Uncomment to make startup quicker during debugging.
	//args = []string{"code.google.com/p/go.tools/cmd/godoc"}
	//args = []string{"fmt"}

	if _, err := conf.FromArgs(args, true); err != nil {
		log.Print(err) // import error
		return
	}

	log.Print("Loading and type-checking packages...")
	iprog, err := conf.Load()
	if iprog != nil {
		log.Printf("Loaded %d packages.", len(iprog.AllPackages))
	}
	if err != nil {
		// TODO(adonovan): loader: don't give up just because
		// of one parse error.
		log.Print(err) // parse error in some package
		return
	}

	// Create SSA-form program representation.
	// Only the transitively error-free packages are used.
	prog := ssa.Create(iprog, ssa.GlobalDebug)

	// Compute the set of main packages, including testmain.
	allPackages := prog.AllPackages()
	var mainPkgs []*ssa.Package
	if testmain := prog.CreateTestMainPackage(allPackages...); testmain != nil {
		mainPkgs = append(mainPkgs, testmain)
	}
	for _, pkg := range allPackages {
		if pkg.Object.Name() == "main" && pkg.Func("main") != nil {
			mainPkgs = append(mainPkgs, pkg)
		}
	}
	log.Print("Main packages: ", mainPkgs)

	// Build SSA code for bodies of all functions in the whole program.
	log.Print("Building SSA...")
	prog.BuildAll()
	log.Print("SSA building complete")

	a := analysis{
		result: result,
		prog:   prog,
		pcgs:   make(map[*ssa.Package]*packageCallGraph),
	}

	// Build a mapping from openable filenames to godoc file URLs,
	// i.e. "/src/pkg/" plus path relative to GOROOT/src/pkg or GOPATH[i]/src.
	a.path2url = make(map[string]string)
	for _, info := range iprog.AllPackages {
	nextfile:
		for _, f := range info.Files {
			abs := iprog.Fset.File(f.Pos()).Name()
			// Find the root to which this file belongs.
			for _, root := range roots {
				rel := strings.TrimPrefix(abs, root)
				if len(rel) < len(abs) {
					a.path2url[abs] = "/src/pkg/" + filepath.ToSlash(rel)
					continue nextfile
				}
			}

			log.Printf("Can't locate file %s (package %q) beneath any root",
//.........这里部分代码省略.........

func main() {
	flag.Usage = func() {
		fmt.Fprintf(os.Stderr, "Usage: errorpaths scope pkg-pattern\n")
		fmt.Fprint(os.Stderr, loader.FromArgsUsage)
	}
	flag.Parse()
	args := flag.Args()
	if len(args) != 2 {
		flag.Usage()
	}
	conf := loader.Config{
		SourceImports: true,
	}
	_, err := conf.FromArgs(args[0:1])
	if err != nil {
		log.Fatalf("cannot initialise loader: %v", err)
	}
	pkgPat, err := regexp.Compile("^" + args[1] + "$")
	if err != nil {
		log.Fatalf("cann compile regexp %q: %s", args[1], err)
	}
	lprog, err := conf.Load()
	if err != nil {
		log.Fatalf("cannot load program: %v", err)
	}
	or, err := oracle.New(lprog, nil, false)
	if err != nil {
		log.Fatalf("cannot make oracle: %v", err)
	}
	ssaProg := ssa.Create(lprog, ssa.SanityCheckFunctions)
	ctxt := &context{
		lprog:   lprog,
		ssaProg: ssaProg,
		oracle:  or,
		infos:   make(map[*ssa.Function]*errorInfo),
		locs:    make(map[*ssa.Function]errorLocations),
	}

	var foundPkgs []*types.Package
	log.Printf("searching %d packages", len(lprog.AllPackages))

	for pkg, _ := range lprog.AllPackages {
		if pkgPat.MatchString(pkg.Path()) {
			foundPkgs = append(foundPkgs, pkg)
			break
		}
	}
	if len(foundPkgs) == 0 {
		log.Fatalf("failed to find any matching packages")
	}
	for _, pkg := range foundPkgs {
		log.Printf("package %s", pkg.Name())
		ssaPkg := ssaProg.Package(pkg)
		ssaPkg.Build()
		for name, m := range ssaPkg.Members {
			log.Printf("name %s", name)
			if f, ok := m.(*ssa.Function); ok && returnsError(f) {
				fmt.Printf("%s\n", f)
				locs := ctxt.errorLocations(f)
				ctxt.dumpErrorLocs(locs, os.Stdout, "\t")
			}
		}
	}
}

// Tests that synthesized init functions are correctly formed.
// Bare init functions omit calls to dependent init functions and the use of
// an init guard. They are useful in cases where the client uses a different
// calling convention for init functions, or cases where it is easier for a
// client to analyze bare init functions. Both of these aspects are used by
// the llgo compiler for simpler integration with gccgo's runtime library,
// and to simplify the analysis whereby it deduces which stores to globals
// can be lowered to global initializers.
func TestInit(t *testing.T) {
	tests := []struct {
		mode        ssa.BuilderMode
		input, want string
	}{
		{0, `package A; import _ "errors"; var i int = 42`,
			`# Name: A.init
# Package: A
# Synthetic: package initializer
func init():
0:                                                                entry P:0 S:2
	t0 = *init$guard                                                   bool
	if t0 goto 2 else 1
1:                                                           init.start P:1 S:1
	*init$guard = true:bool
	t1 = errors.init()                                                   ()
	*i = 42:int
	jump 2
2:                                                            init.done P:2 S:0
	return

`},
		{ssa.BareInits, `package B; import _ "errors"; var i int = 42`,
			`# Name: B.init
# Package: B
# Synthetic: package initializer
func init():
0:                                                                entry P:0 S:0
	*i = 42:int
	return

`},
	}
	for _, test := range tests {
		// Create a single-file main package.
		var conf loader.Config
		f, err := conf.ParseFile("<input>", test.input)
		if err != nil {
			t.Errorf("test %q: %s", test.input[:15], err)
			continue
		}
		conf.CreateFromFiles(f.Name.Name, f)

		iprog, err := conf.Load()
		if err != nil {
			t.Errorf("test 'package %s': Load: %s", f.Name.Name, err)
			continue
		}
		prog := ssa.Create(iprog, test.mode)
		mainPkg := prog.Package(iprog.Created[0].Pkg)
		prog.BuildAll()
		initFunc := mainPkg.Func("init")
		if initFunc == nil {
			t.Errorf("test 'package %s': no init function", f.Name.Name)
			continue
		}

		var initbuf bytes.Buffer
		_, err = initFunc.WriteTo(&initbuf)
		if err != nil {
			t.Errorf("test 'package %s': WriteTo: %s", f.Name.Name, err)
			continue
		}

		if initbuf.String() != test.want {
			t.Errorf("test 'package %s': got %q, want %q", f.Name.Name, initbuf.String(), test.want)
		}
	}
}

func run(t *testing.T, dir, input string, success successPredicate) bool {
	fmt.Printf("Input: %s\n", input)

	start := time.Now()

	var inputs []string
	for _, i := range strings.Split(input, " ") {
		if strings.HasSuffix(i, ".go") {
			i = dir + i
		}
		inputs = append(inputs, i)
	}

	conf := loader.Config{SourceImports: true}
	if _, err := conf.FromArgs(inputs, true); err != nil {
		t.Errorf("FromArgs(%s) failed: %s", inputs, err)
		return false
	}

	conf.Import("runtime")

	// Print a helpful hint if we don't make it to the end.
	var hint string
	defer func() {
		if hint != "" {
			fmt.Println("FAIL")
			fmt.Println(hint)
		} else {
			fmt.Println("PASS")
		}

		interp.CapturedOutput = nil
	}()

	hint = fmt.Sprintf("To dump SSA representation, run:\n%% go build code.google.com/p/go.tools/cmd/ssadump && ./ssadump -build=CFP %s\n", input)

	iprog, err := conf.Load()
	if err != nil {
		t.Errorf("conf.Load(%s) failed: %s", inputs, err)
		return false
	}

	prog := ssa.Create(iprog, ssa.SanityCheckFunctions)
	prog.BuildAll()

	var mainPkg *ssa.Package
	var initialPkgs []*ssa.Package
	for _, info := range iprog.InitialPackages() {
		if info.Pkg.Path() == "runtime" {
			continue // not an initial package
		}
		p := prog.Package(info.Pkg)
		initialPkgs = append(initialPkgs, p)
		if mainPkg == nil && p.Func("main") != nil {
			mainPkg = p
		}
	}
	if mainPkg == nil {
		testmainPkg := prog.CreateTestMainPackage(initialPkgs...)
		if testmainPkg == nil {
			t.Errorf("CreateTestMainPackage(%s) returned nil", mainPkg)
			return false
		}
		if testmainPkg.Func("main") == nil {
			t.Errorf("synthetic testmain package has no main")
			return false
		}
		mainPkg = testmainPkg
	}

	var out bytes.Buffer
	interp.CapturedOutput = &out

	hint = fmt.Sprintf("To trace execution, run:\n%% go build code.google.com/p/go.tools/cmd/ssadump && ./ssadump -build=C -run --interp=T %s\n", input)
	exitCode := interp.Interpret(mainPkg, 0, &types.StdSizes{8, 8}, inputs[0], []string{})

	// The definition of success varies with each file.
	if err := success(exitCode, out.String()); err != nil {
		t.Errorf("interp.Interpret(%s) failed: %s", inputs, err)
		return false
	}

	hint = "" // call off the hounds

	if false {
		fmt.Println(input, time.Since(start)) // test profiling
	}

	return true
}

// Tests that programs partially loaded from gc object files contain
// functions with no code for the external portions, but are otherwise ok.
func TestExternalPackages(t *testing.T) {
	test := `
package main

import (
	"bytes"
	"io"
	"testing"
)

func main() {
        var t testing.T
	t.Parallel()    // static call to external declared method
        t.Fail()        // static call to promoted external declared method
        testing.Short() // static call to external package-level function

        var w io.Writer = new(bytes.Buffer)
        w.Write(nil)    // interface invoke of external declared method
}
`

	// Create a single-file main package.
	var conf loader.Config
	f, err := conf.ParseFile("<input>", test, 0)
	if err != nil {
		t.Error(err)
		return
	}
	conf.CreateFromFiles("main", f)

	iprog, err := conf.Load()
	if err != nil {
		t.Error(err)
		return
	}

	prog := ssa.Create(iprog, ssa.SanityCheckFunctions)
	mainPkg := prog.Package(iprog.Created[0].Pkg)
	mainPkg.Build()

	// The main package, its direct and indirect dependencies are loaded.
	deps := []string{
		// directly imported dependencies:
		"bytes", "io", "testing",
		// indirect dependencies (partial list):
		"errors", "fmt", "os", "runtime",
	}

	all := prog.AllPackages()
	if len(all) <= len(deps) {
		t.Errorf("unexpected set of loaded packages: %q", all)
	}
	for _, path := range deps {
		pkg := prog.ImportedPackage(path)
		if pkg == nil {
			t.Errorf("package not loaded: %q", path)
			continue
		}

		// External packages should have no function bodies (except for wrappers).
		isExt := pkg != mainPkg

		// init()
		if isExt && !isEmpty(pkg.Func("init")) {
			t.Errorf("external package %s has non-empty init", pkg)
		} else if !isExt && isEmpty(pkg.Func("init")) {
			t.Errorf("main package %s has empty init", pkg)
		}

		for _, mem := range pkg.Members {
			switch mem := mem.(type) {
			case *ssa.Function:
				// Functions at package level.
				if isExt && !isEmpty(mem) {
					t.Errorf("external function %s is non-empty", mem)
				} else if !isExt && isEmpty(mem) {
					t.Errorf("function %s is empty", mem)
				}

			case *ssa.Type:
				// Methods of named types T.
				// (In this test, all exported methods belong to *T not T.)
				if !isExt {
					t.Fatalf("unexpected name type in main package: %s", mem)
				}
				mset := prog.MethodSets.MethodSet(types.NewPointer(mem.Type()))
				for i, n := 0, mset.Len(); i < n; i++ {
					m := prog.Method(mset.At(i))
					// For external types, only synthetic wrappers have code.
					expExt := !strings.Contains(m.Synthetic, "wrapper")
					if expExt && !isEmpty(m) {
						t.Errorf("external method %s is non-empty: %s",
							m, m.Synthetic)
					} else if !expExt && isEmpty(m) {
						t.Errorf("method function %s is empty: %s",
							m, m.Synthetic)
					}
				}
//.........这里部分代码省略.........

func doMain() error {
	flag.Parse()
	args := flag.Args()

	conf := loader.Config{
		Build:         &build.Default,
		SourceImports: true,
	}
	// TODO(adonovan): make go/types choose its default Sizes from
	// build.Default or a specified *build.Context.
	var wordSize int64 = 8
	switch conf.Build.GOARCH {
	case "386", "arm":
		wordSize = 4
	}
	conf.TypeChecker.Sizes = &types.StdSizes{
		MaxAlign: 8,
		WordSize: wordSize,
	}

	var mode ssa.BuilderMode
	for _, c := range *buildFlag {
		switch c {
		case 'D':
			mode |= ssa.GlobalDebug
		case 'P':
			mode |= ssa.LogPackages | ssa.BuildSerially
		case 'F':
			mode |= ssa.LogFunctions | ssa.BuildSerially
		case 'S':
			mode |= ssa.LogSource | ssa.BuildSerially
		case 'C':
			mode |= ssa.SanityCheckFunctions
		case 'N':
			mode |= ssa.NaiveForm
		case 'G':
			conf.SourceImports = false
		case 'L':
			mode |= ssa.BuildSerially
		default:
			return fmt.Errorf("unknown -build option: '%c'", c)
		}
	}

	var interpMode interp.Mode
	for _, c := range *interpFlag {
		switch c {
		case 'T':
			interpMode |= interp.EnableTracing
		case 'R':
			interpMode |= interp.DisableRecover
		default:
			fmt.Fprintf(os.Stderr, "ssadump: unknown -interp option: '%c'.", c)
			os.Exit(1)
		}
	}

	if len(args) == 0 {
		fmt.Fprint(os.Stderr, usage)
		os.Exit(1)
	}

	// Profiling support.
	if *cpuprofile != "" {
		f, err := os.Create(*cpuprofile)
		if err != nil {
			fmt.Fprintln(os.Stderr, err)
			os.Exit(1)
		}
		pprof.StartCPUProfile(f)
		defer pprof.StopCPUProfile()
	}

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

	// The interpreter needs the runtime package.
	if *runFlag {
		conf.Import("runtime")
	}

	// 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, mode)
	prog.BuildAll()

	// Run the interpreter.
	if *runFlag {
		var main *ssa.Package
		pkgs := prog.AllPackages()
		if *testFlag {
			// If -test, run all packages' tests.
//.........这里部分代码省略.........