Example #1
0
// testMainSlice emits to fn code to construct a slice of type slice
// (one of []testing.Internal{Test,Benchmark,Example}) for all
// functions in expfuncs whose name starts with prefix (one of
// "Test", "Benchmark" or "Example") and whose type is appropriate.
// It returns the slice value.
//
func testMainSlice(fn *Function, expfuncs []*Function, prefix string, slice types.Type) Value {
	tElem := slice.(*types.Slice).Elem()
	tFunc := tElem.Underlying().(*types.Struct).Field(1).Type()

	var testfuncs []*Function
	for _, f := range expfuncs {
		if isTest(f.Name(), prefix) && types.Identical(f.Signature, tFunc) {
			testfuncs = append(testfuncs, f)
		}
	}
	if testfuncs == nil {
		return nilConst(slice)
	}

	tPtrString := types.NewPointer(tString)
	tPtrElem := types.NewPointer(tElem)
	tPtrFunc := types.NewPointer(tFunc)

	// Emit: array = new [n]testing.InternalTest
	tArray := types.NewArray(tElem, int64(len(testfuncs)))
	array := emitNew(fn, tArray, token.NoPos)
	array.Comment = "test main"
	for i, testfunc := range testfuncs {
		// Emit: pitem = &array[i]
		ia := &IndexAddr{X: array, Index: intConst(int64(i))}
		ia.setType(tPtrElem)
		pitem := fn.emit(ia)

		// Emit: pname = &pitem.Name
		fa := &FieldAddr{X: pitem, Field: 0} // .Name
		fa.setType(tPtrString)
		pname := fn.emit(fa)

		// Emit: *pname = "testfunc"
		emitStore(fn, pname, stringConst(testfunc.Name()))

		// Emit: pfunc = &pitem.F
		fa = &FieldAddr{X: pitem, Field: 1} // .F
		fa.setType(tPtrFunc)
		pfunc := fn.emit(fa)

		// Emit: *pfunc = testfunc
		emitStore(fn, pfunc, testfunc)
	}

	// Emit: slice array[:]
	sl := &Slice{X: array}
	sl.setType(slice)
	return fn.emit(sl)
}
Example #2
0
// emitImplicitSelections emits to f code to apply the sequence of
// implicit field selections specified by indices to base value v, and
// returns the selected value.
//
// If v is the address of a struct, the result will be the address of
// a field; if it is the value of a struct, the result will be the
// value of a field.
//
func emitImplicitSelections(f *Function, v Value, indices []int) Value {
	for _, index := range indices {
		fld := deref(v.Type()).Underlying().(*types.Struct).Field(index)

		if isPointer(v.Type()) {
			instr := &FieldAddr{
				X:     v,
				Field: index,
			}
			instr.setType(types.NewPointer(fld.Type()))
			v = f.emit(instr)
			// Load the field's value iff indirectly embedded.
			if isPointer(fld.Type()) {
				v = emitLoad(f, v)
			}
		} else {
			instr := &Field{
				X:     v,
				Field: index,
			}
			instr.setType(fld.Type())
			v = f.emit(instr)
		}
	}
	return v
}
Example #3
0
// emitFieldSelection emits to f code to select the index'th field of v.
//
// If wantAddr, the input must be a pointer-to-struct and the result
// will be the field's address; otherwise the result will be the
// field's value.
//
func emitFieldSelection(f *Function, v Value, index int, wantAddr bool, pos token.Pos) Value {
	fld := deref(v.Type()).Underlying().(*types.Struct).Field(index)
	if isPointer(v.Type()) {
		instr := &FieldAddr{
			X:     v,
			Field: index,
		}
		instr.setPos(pos)
		instr.setType(types.NewPointer(fld.Type()))
		v = f.emit(instr)
		// Load the field's value iff we don't want its address.
		if !wantAddr {
			v = emitLoad(f, v)
		}
	} else {
		instr := &Field{
			X:     v,
			Field: index,
		}
		instr.setPos(pos)
		instr.setType(fld.Type())
		v = f.emit(instr)
	}
	return v
}
Example #4
0
// emitNew emits to f a new (heap Alloc) instruction allocating an
// object of type typ.  pos is the optional source location.
//
func emitNew(f *Function, typ types.Type, pos token.Pos) *Alloc {
	v := &Alloc{Heap: true}
	v.setType(types.NewPointer(typ))
	v.setPos(pos)
	f.emit(v)
	return v
}
Example #5
0
// addLocal creates an anonymous local variable of type typ, adds it
// to function f and returns it.  pos is the optional source location.
//
func (f *Function) addLocal(typ types.Type, pos token.Pos) *Alloc {
	v := &Alloc{}
	v.setType(types.NewPointer(typ))
	v.setPos(pos)
	f.Locals = append(f.Locals, v)
	f.emit(v)
	return v
}
Example #6
0
// addSpilledParam declares a parameter that is pre-spilled to the
// stack; the function body will load/store the spilled location.
// Subsequent lifting will eliminate spills where possible.
//
func (f *Function) addSpilledParam(obj types.Object) {
	param := f.addParamObj(obj)
	spill := &Alloc{Comment: obj.Name()}
	spill.setType(types.NewPointer(obj.Type()))
	spill.setPos(obj.Pos())
	f.objects[obj] = spill
	f.Locals = append(f.Locals, spill)
	f.emit(spill)
	f.emit(&Store{Addr: spill, Val: param})
}
Example #7
0
// memberFromObject populates package pkg with a member for the
// typechecker object obj.
//
// For objects from Go source code, syntax is the associated syntax
// tree (for funcs and vars only); it will be used during the build
// phase.
//
func memberFromObject(pkg *Package, obj types.Object, syntax ast.Node) {
	name := obj.Name()
	switch obj := obj.(type) {
	case *types.TypeName:
		pkg.Members[name] = &Type{
			object: obj,
			pkg:    pkg,
		}

	case *types.Const:
		c := &NamedConst{
			object: obj,
			Value:  NewConst(obj.Val(), obj.Type()),
			pkg:    pkg,
		}
		pkg.values[obj] = c.Value
		pkg.Members[name] = c

	case *types.Var:
		g := &Global{
			Pkg:    pkg,
			name:   name,
			object: obj,
			typ:    types.NewPointer(obj.Type()), // address
			pos:    obj.Pos(),
		}
		pkg.values[obj] = g
		pkg.Members[name] = g

	case *types.Func:
		fn := &Function{
			name:      name,
			object:    obj,
			Signature: obj.Type().(*types.Signature),
			syntax:    syntax,
			pos:       obj.Pos(),
			Pkg:       pkg,
			Prog:      pkg.Prog,
		}
		if syntax == nil {
			fn.Synthetic = "loaded from gc object file"
		}

		pkg.values[obj] = fn
		if fn.Signature.Recv() == nil {
			pkg.Members[name] = fn // package-level function
		}

	default: // (incl. *types.Package)
		panic("unexpected Object type: " + obj.String())
	}
}
Example #8
0
// Type =
//	BasicType | TypeName | ArrayType | SliceType | StructType |
//      PointerType | FuncType | InterfaceType | MapType | ChanType |
//      "(" Type ")" .
//
// BasicType   = ident .
// TypeName    = ExportedName .
// SliceType   = "[" "]" Type .
// PointerType = "*" Type .
// FuncType    = "func" Signature .
//
func (p *parser) parseType() types.Type {
	switch p.tok {
	case scanner.Ident:
		switch p.lit {
		default:
			return p.parseBasicType()
		case "struct":
			return p.parseStructType()
		case "func":
			// FuncType
			p.next()
			return p.parseSignature(nil)
		case "interface":
			return p.parseInterfaceType()
		case "map":
			return p.parseMapType()
		case "chan":
			return p.parseChanType()
		}
	case '@':
		// TypeName
		pkg, name := p.parseExportedName()
		return declTypeName(pkg, name).Type()
	case '[':
		p.next() // look ahead
		if p.tok == ']' {
			// SliceType
			p.next()
			return types.NewSlice(p.parseType())
		}
		return p.parseArrayType()
	case '*':
		// PointerType
		p.next()
		return types.NewPointer(p.parseType())
	case '<':
		return p.parseChanType()
	case '(':
		// "(" Type ")"
		p.next()
		typ := p.parseType()
		p.expect(')')
		return typ
	}
	p.errorf("expected type, got %s (%q)", scanner.TokenString(p.tok), p.lit)
	return nil
}
Example #9
0
// IntuitiveMethodSet returns the intuitive method set of a type, T.
//
// The result contains MethodSet(T) and additionally, if T is a
// concrete type, methods belonging to *T if there is no identically
// named method on T itself.  This corresponds to user intuition about
// method sets; this function is intended only for user interfaces.
//
// The order of the result is as for types.MethodSet(T).
//
func IntuitiveMethodSet(T types.Type, msets *types.MethodSetCache) []*types.Selection {
	var result []*types.Selection
	mset := msets.MethodSet(T)
	if _, ok := T.Underlying().(*types.Interface); ok {
		for i, n := 0, mset.Len(); i < n; i++ {
			result = append(result, mset.At(i))
		}
	} else {
		pmset := msets.MethodSet(types.NewPointer(T))
		for i, n := 0, pmset.Len(); i < n; i++ {
			meth := pmset.At(i)
			if m := mset.Lookup(meth.Obj().Pkg(), meth.Obj().Name()); m != nil {
				meth = m
			}
			result = append(result, meth)
		}
	}
	return result
}
Example #10
0
// Smoke test to ensure that imported methods get the correct package.
func TestCorrectMethodPackage(t *testing.T) {
	// This package does not handle gccgo export data.
	if runtime.Compiler == "gccgo" {
		return
	}

	imports := make(map[string]*types.Package)
	_, err := Import(imports, "net/http")
	if err != nil {
		t.Fatal(err)
	}

	mutex := imports["sync"].Scope().Lookup("Mutex").(*types.TypeName).Type()
	mset := types.NewMethodSet(types.NewPointer(mutex)) // methods of *sync.Mutex
	sel := mset.Lookup(nil, "Lock")
	lock := sel.Obj().(*types.Func)
	if got, want := lock.Pkg().Path(), "sync"; got != want {
		t.Errorf("got package path %q; want %q", got, want)
	}
}
Example #11
0
// findNamedFunc returns the named function whose FuncDecl.Ident is at
// position pos.
//
func findNamedFunc(pkg *Package, pos token.Pos) *Function {
	// Look at all package members and method sets of named types.
	// Not very efficient.
	for _, mem := range pkg.Members {
		switch mem := mem.(type) {
		case *Function:
			if mem.Pos() == pos {
				return mem
			}
		case *Type:
			mset := pkg.Prog.MethodSets.MethodSet(types.NewPointer(mem.Type()))
			for i, n := 0, mset.Len(); i < n; i++ {
				// Don't call Program.Method: avoid creating wrappers.
				obj := mset.At(i).Obj().(*types.Func)
				if obj.Pos() == pos {
					return pkg.values[obj].(*Function)
				}
			}
		}
	}
	return nil
}
Example #12
0
func checkVarValue(t *testing.T, prog *ssa.Program, pkg *ssa.Package, ref []ast.Node, obj *types.Var, expKind string, wantAddr bool) {
	// The prefix of all assertions messages.
	prefix := fmt.Sprintf("VarValue(%s @ L%d)",
		obj, prog.Fset.Position(ref[0].Pos()).Line)

	v, gotAddr := prog.VarValue(obj, pkg, ref)

	// Kind is the concrete type of the ssa Value.
	gotKind := "nil"
	if v != nil {
		gotKind = fmt.Sprintf("%T", v)[len("*ssa."):]
	}

	// fmt.Printf("%s = %v (kind %q; expect %q) wantAddr=%t gotAddr=%t\n", prefix, v, gotKind, expKind, wantAddr, gotAddr) // debugging

	// Check the kinds match.
	// "nil" indicates expected failure (e.g. optimized away).
	if expKind != gotKind {
		t.Errorf("%s concrete type == %s, want %s", prefix, gotKind, expKind)
	}

	// Check the types match.
	// If wantAddr, the expected type is the object's address.
	if v != nil {
		expType := obj.Type()
		if wantAddr {
			expType = types.NewPointer(expType)
			if !gotAddr {
				t.Errorf("%s: got value, want address", prefix)
			}
		} else if gotAddr {
			t.Errorf("%s: got address, want value", prefix)
		}
		if !types.Identical(v.Type(), expType) {
			t.Errorf("%s.Type() == %s, want %s", prefix, v.Type(), expType)
		}
	}
}
Example #13
0
func ext۰reflect۰New(fr *frame, args []value) value {
	// Signature: func (t reflect.Type) reflect.Value
	t := args[0].(iface).v.(rtype).t
	alloc := zero(t)
	return makeReflectValue(types.NewPointer(t), &alloc)
}
Example #14
0
// Analyze runs the pointer analysis with the scope and options
// specified by config, and returns the (synthetic) root of the callgraph.
//
// Pointer analysis of a transitively closed well-typed program should
// always succeed.  An error can occur only due to an internal bug.
//
func Analyze(config *Config) (result *Result, err error) {
	if config.Mains == nil {
		return nil, fmt.Errorf("no main/test packages to analyze (check $GOROOT/$GOPATH)")
	}
	defer func() {
		if p := recover(); p != nil {
			err = fmt.Errorf("internal error in pointer analysis: %v (please report this bug)", p)
			fmt.Fprintln(os.Stderr, "Internal panic in pointer analysis:")
			debug.PrintStack()
		}
	}()

	a := &analysis{
		config:      config,
		log:         config.Log,
		prog:        config.prog(),
		globalval:   make(map[ssa.Value]nodeid),
		globalobj:   make(map[ssa.Value]nodeid),
		flattenMemo: make(map[types.Type][]*fieldInfo),
		trackTypes:  make(map[types.Type]bool),
		atFuncs:     make(map[*ssa.Function]bool),
		hasher:      typeutil.MakeHasher(),
		intrinsics:  make(map[*ssa.Function]intrinsic),
		result: &Result{
			Queries:         make(map[ssa.Value]Pointer),
			IndirectQueries: make(map[ssa.Value]Pointer),
		},
		deltaSpace: make([]int, 0, 100),
	}

	if false {
		a.log = os.Stderr // for debugging crashes; extremely verbose
	}

	if a.log != nil {
		fmt.Fprintln(a.log, "==== Starting analysis")
	}

	// Pointer analysis requires a complete program for soundness.
	// Check to prevent accidental misconfiguration.
	for _, pkg := range a.prog.AllPackages() {
		// (This only checks that the package scope is complete,
		// not that func bodies exist, but it's a good signal.)
		if !pkg.Object.Complete() {
			return nil, fmt.Errorf(`pointer analysis requires a complete program yet package %q was incomplete (set loader.Config.SourceImports during loading)`, pkg.Object.Path())
		}
	}

	if reflect := a.prog.ImportedPackage("reflect"); reflect != nil {
		rV := reflect.Object.Scope().Lookup("Value")
		a.reflectValueObj = rV
		a.reflectValueCall = a.prog.LookupMethod(rV.Type(), nil, "Call")
		a.reflectType = reflect.Object.Scope().Lookup("Type").Type().(*types.Named)
		a.reflectRtypeObj = reflect.Object.Scope().Lookup("rtype")
		a.reflectRtypePtr = types.NewPointer(a.reflectRtypeObj.Type())

		// Override flattening of reflect.Value, treating it like a basic type.
		tReflectValue := a.reflectValueObj.Type()
		a.flattenMemo[tReflectValue] = []*fieldInfo{{typ: tReflectValue}}

		// Override shouldTrack of reflect.Value and *reflect.rtype.
		// Always track pointers of these types.
		a.trackTypes[tReflectValue] = true
		a.trackTypes[a.reflectRtypePtr] = true

		a.rtypes.SetHasher(a.hasher)
		a.reflectZeros.SetHasher(a.hasher)
	}
	if runtime := a.prog.ImportedPackage("runtime"); runtime != nil {
		a.runtimeSetFinalizer = runtime.Func("SetFinalizer")
	}
	a.computeTrackBits()

	a.generate()
	a.showCounts()

	if optRenumber {
		a.renumber()
	}

	N := len(a.nodes) // excludes solver-created nodes

	if optHVN {
		if debugHVNCrossCheck {
			// Cross-check: run the solver once without
			// optimization, once with, and compare the
			// solutions.
			savedConstraints := a.constraints

			a.solve()
			a.dumpSolution("A.pts", N)

			// Restore.
			a.constraints = savedConstraints
			for _, n := range a.nodes {
				n.solve = new(solverState)
			}
			a.nodes = a.nodes[:N]

			// rtypes is effectively part of the solver state.
			a.rtypes = typeutil.Map{}
			a.rtypes.SetHasher(a.hasher)
		}

		a.hvn()
	}

	if debugHVNCrossCheck {
		runtime.GC()
		runtime.GC()
	}

	a.solve()

	// Compare solutions.
	if optHVN && debugHVNCrossCheck {
		a.dumpSolution("B.pts", N)

		if !diff("A.pts", "B.pts") {
			return nil, fmt.Errorf("internal error: optimization changed solution")
		}
	}

	// Create callgraph.Nodes in deterministic order.
	if cg := a.result.CallGraph; cg != nil {
		for _, caller := range a.cgnodes {
			cg.CreateNode(caller.fn)
		}
	}

	// Add dynamic edges to call graph.
	var space [100]int
	for _, caller := range a.cgnodes {
		for _, site := range caller.sites {
			for _, callee := range a.nodes[site.targets].solve.pts.AppendTo(space[:0]) {
				a.callEdge(caller, site, nodeid(callee))
			}
		}
	}

	return a.result, nil
}
Example #15
0
// CreatePackage constructs and returns an SSA Package from an
// error-free package described by info, and populates its Members
// mapping.
//
// Repeated calls with the same info return the same Package.
//
// The real work of building SSA form for each function is not done
// until a subsequent call to Package.Build().
//
func (prog *Program) CreatePackage(info *loader.PackageInfo) *Package {
	if p := prog.packages[info.Pkg]; p != nil {
		return p // already loaded
	}

	p := &Package{
		Prog:    prog,
		Members: make(map[string]Member),
		values:  make(map[types.Object]Value),
		Object:  info.Pkg,
		info:    info, // transient (CREATE and BUILD phases)
	}

	// Add init() function.
	p.init = &Function{
		name:      "init",
		Signature: new(types.Signature),
		Synthetic: "package initializer",
		Pkg:       p,
		Prog:      prog,
	}
	p.Members[p.init.name] = p.init

	// CREATE phase.
	// Allocate all package members: vars, funcs, consts and types.
	if len(info.Files) > 0 {
		// Go source package.
		for _, file := range info.Files {
			for _, decl := range file.Decls {
				membersFromDecl(p, decl)
			}
		}
	} else {
		// GC-compiled binary package.
		// No code.
		// No position information.
		scope := p.Object.Scope()
		for _, name := range scope.Names() {
			obj := scope.Lookup(name)
			memberFromObject(p, obj, nil)
			if obj, ok := obj.(*types.TypeName); ok {
				named := obj.Type().(*types.Named)
				for i, n := 0, named.NumMethods(); i < n; i++ {
					memberFromObject(p, named.Method(i), nil)
				}
			}
		}
	}

	if prog.mode&BareInits == 0 {
		// Add initializer guard variable.
		initguard := &Global{
			Pkg:  p,
			name: "init$guard",
			typ:  types.NewPointer(tBool),
		}
		p.Members[initguard.Name()] = initguard
	}

	if prog.mode&GlobalDebug != 0 {
		p.SetDebugMode(true)
	}

	if prog.mode&LogPackages != 0 {
		p.WriteTo(os.Stderr)
	}

	if info.Importable {
		prog.imported[info.Pkg.Path()] = p
	}
	prog.packages[p.Object] = p

	return p
}
Example #16
0
// computeImplements computes the "implements" relation over all pairs
// of named types in allNamed.
func computeImplements(cache *types.MethodSetCache, allNamed []*types.Named) map[*types.Named]implementsFacts {
	// Information about a single type's method set.
	type msetInfo struct {
		typ          types.Type
		mset         *types.MethodSet
		mask1, mask2 uint64
	}

	initMsetInfo := func(info *msetInfo, typ types.Type) {
		info.typ = typ
		info.mset = cache.MethodSet(typ)
		for i := 0; i < info.mset.Len(); i++ {
			name := info.mset.At(i).Obj().Name()
			info.mask1 |= 1 << methodBit(name[0])
			info.mask2 |= 1 << methodBit(name[len(name)-1])
		}
	}

	// satisfies(T, U) reports whether type T satisfies type U.
	// U must be an interface.
	//
	// Since there are thousands of types (and thus millions of
	// pairs of types) and types.Assignable(T, U) is relatively
	// expensive, we compute assignability directly from the
	// method sets.  (At least one of T and U must be an
	// interface.)
	//
	// We use a trick (thanks gri!) related to a Bloom filter to
	// quickly reject most tests, which are false.  For each
	// method set, we precompute a mask, a set of bits, one per
	// distinct initial byte of each method name.  Thus the mask
	// for io.ReadWriter would be {'R','W'}.  AssignableTo(T, U)
	// cannot be true unless mask(T)&mask(U)==mask(U).
	//
	// As with a Bloom filter, we can improve precision by testing
	// additional hashes, e.g. using the last letter of each
	// method name, so long as the subset mask property holds.
	//
	// When analyzing the standard library, there are about 1e6
	// calls to satisfies(), of which 0.6% return true.  With a
	// 1-hash filter, 95% of calls avoid the expensive check; with
	// a 2-hash filter, this grows to 98.2%.
	satisfies := func(T, U *msetInfo) bool {
		return T.mask1&U.mask1 == U.mask1 &&
			T.mask2&U.mask2 == U.mask2 &&
			containsAllIdsOf(T.mset, U.mset)
	}

	// Information about a named type N, and perhaps also *N.
	type namedInfo struct {
		isInterface bool
		base        msetInfo // N
		ptr         msetInfo // *N, iff N !isInterface
	}

	var infos []namedInfo

	// Precompute the method sets and their masks.
	for _, N := range allNamed {
		var info namedInfo
		initMsetInfo(&info.base, N)
		_, info.isInterface = N.Underlying().(*types.Interface)
		if !info.isInterface {
			initMsetInfo(&info.ptr, types.NewPointer(N))
		}

		if info.base.mask1|info.ptr.mask1 == 0 {
			continue // neither N nor *N has methods
		}

		infos = append(infos, info)
	}

	facts := make(map[*types.Named]implementsFacts)

	// Test all pairs of distinct named types (T, U).
	// TODO(adonovan): opt: compute (U, T) at the same time.
	for t := range infos {
		T := &infos[t]
		var to, from, fromPtr []types.Type
		for u := range infos {
			if t == u {
				continue
			}
			U := &infos[u]
			switch {
			case T.isInterface && U.isInterface:
				if satisfies(&U.base, &T.base) {
					to = append(to, U.base.typ)
				}
				if satisfies(&T.base, &U.base) {
					from = append(from, U.base.typ)
				}
			case T.isInterface: // U concrete
				if satisfies(&U.base, &T.base) {
					to = append(to, U.base.typ)
				} else if satisfies(&U.ptr, &T.base) {
					to = append(to, U.ptr.typ)
				}
			case U.isInterface: // T concrete
				if satisfies(&T.base, &U.base) {
					from = append(from, U.base.typ)
				} else if satisfies(&T.ptr, &U.base) {
					fromPtr = append(fromPtr, U.base.typ)
				}
			}
		}

		// Sort types (arbitrarily) to avoid nondeterminism.
		sort.Sort(typesByString(to))
		sort.Sort(typesByString(from))
		sort.Sort(typesByString(fromPtr))

		facts[T.base.typ.(*types.Named)] = implementsFacts{to, from, fromPtr}
	}

	return facts
}
Example #17
0
// TODO(adonovan):
// - test use of explicit hasher across two maps.
// - test hashcodes are consistent with equals for a range of types
//   (e.g. all types generated by type-checking some body of real code).

import (
	"testing"

	"github.com/nathankerr/godocbook/Godeps/_workspace/src/code.google.com/p/go.tools/go/types"
	"github.com/nathankerr/godocbook/Godeps/_workspace/src/code.google.com/p/go.tools/go/types/typeutil"
)

var (
	tStr      = types.Typ[types.String]             // string
	tPStr1    = types.NewPointer(tStr)              // *string
	tPStr2    = types.NewPointer(tStr)              // *string, again
	tInt      = types.Typ[types.Int]                // int
	tChanInt1 = types.NewChan(types.RecvOnly, tInt) // <-chan int
	tChanInt2 = types.NewChan(types.RecvOnly, tInt) // <-chan int, again
)

func checkEqualButNotIdentical(t *testing.T, x, y types.Type, comment string) {
	if !types.Identical(x, y) {
		t.Errorf("%s: not equal: %s, %s", comment, x, y)
	}
	if x == y {
		t.Errorf("%s: identical: %v, %v", comment, x, y)
	}
}
Example #18
0
// 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)
	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)
					}
				}
			}
		}
	}

	expectedCallee := []string{
		"(*testing.T).Parallel",
		"(*testing.common).Fail",
		"testing.Short",
		"N/A",
	}
	callNum := 0
	for _, b := range mainPkg.Func("main").Blocks {
		for _, instr := range b.Instrs {
			switch instr := instr.(type) {
			case ssa.CallInstruction:
				call := instr.Common()
				if want := expectedCallee[callNum]; want != "N/A" {
					got := call.StaticCallee().String()
					if want != got {
						t.Errorf("call #%d from main.main: got callee %s, want %s",
							callNum, got, want)
					}
				}
				callNum++
			}
		}
	}
	if callNum != 4 {
		t.Errorf("in main.main: got %d calls, want %d", callNum, 4)
	}
}