func findMethod(prog *ssa.Program, meth *types.Func, typ types.Type, infer *TypeInfer) *ssa.Function {
if meth != nil {
return prog.LookupMethod(typ, meth.Pkg(), meth.Name())
}
infer.Logger.Fatal(ErrMethodNotFound)
return nil
}
// Create a pointer.Config whose scope is the initial packages of lprog
// and their dependencies.
func setupPTA(prog *ssa.Program, lprog *loader.Program, ptaLog io.Writer, reflection bool) (*pointer.Config, error) {
// TODO(adonovan): the body of this function is essentially
// duplicated in all go/pointer clients. Refactor.
// 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 lprog.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")
}
return &pointer.Config{
Log: ptaLog,
Reflection: reflection,
Mains: mains,
}, nil
}
// mainPackage returns the main package to analyze.
// The resulting package has a main() function.
func mainPackage(prog *ssa.Program, tests bool) (*ssa.Package, error) {
pkgs := prog.AllPackages()
// TODO(adonovan): allow independent control over tests, mains and libraries.
// TODO(adonovan): put this logic in a library; we keep reinventing it.
if tests {
// If -test, use all packages' tests.
if len(pkgs) > 0 {
if main := prog.CreateTestMainPackage(pkgs...); main != nil {
return main, nil
}
}
return nil, fmt.Errorf("no tests")
}
// Otherwise, use the first package named main.
for _, pkg := range pkgs {
if pkg.Object.Name() == "main" {
if pkg.Func("main") == nil {
return nil, fmt.Errorf("no func main() in main package")
}
return pkg, nil
}
}
return nil, fmt.Errorf("no main package")
}
func getFuncs(prog *ssa.Program, pkg *ssa.Package) []*ssa.Function {
funcs := make([]*ssa.Function, 0, len(pkg.Members))
for _, mem := range pkg.Members {
fn, ok := mem.(*ssa.Function)
if ok {
if iu := unicode.IsUpper(rune(fn.Name()[0])); iu || *nonExp {
funcs = append(funcs, fn)
}
}
typ, ok := mem.(*ssa.Type)
if ok {
mset := prog.MethodSets.MethodSet(typ.Type())
for i, n := 0, mset.Len(); i < n; i++ {
if mf := prog.MethodValue(mset.At(i)); mf != nil {
if mfn := mf.Name(); len(mfn) > 0 {
if iu := unicode.IsUpper(rune(mfn[0])); iu || *nonExp {
funcs = append(funcs, mf)
//fmt.Printf("DEBUG method %v %v\n", mfn, mf)
}
}
}
}
}
}
return funcs
}
// GetMainPkg returns main package of a command.
func MainPkg(prog *ssa.Program) *ssa.Package {
pkgs := prog.AllPackages()
for _, pkg := range pkgs {
if pkg.Pkg.Name() == "main" {
return pkg
}
}
return nil // Not found
}
// FindMains returns the set of all packages loaded into the given
// loader.Program which contain main functions
func FindMains(p *loader.Program, s *ssa.Program) []*ssa.Package {
ips := p.InitialPackages()
mains := make([]*ssa.Package, 0, len(ips))
for _, info := range ips {
ssaPkg := s.Package(info.Pkg)
if ssaPkg.Func("main") != nil {
mains = append(mains, ssaPkg)
}
}
return mains
}
// ssaValueForExpr returns the ssa.Value of the non-ast.Ident
// expression whose path to the root of the AST is path.
//
func ssaValueForExpr(prog *ssa.Program, qinfo *loader.PackageInfo, path []ast.Node) (value ssa.Value, isAddr bool, err error) {
pkg := prog.Package(qinfo.Pkg)
pkg.SetDebugMode(true)
pkg.Build()
fn := ssa.EnclosingFunction(pkg, path)
if fn == nil {
return nil, false, fmt.Errorf("no SSA function built for this location (dead code?)")
}
if v, addr := fn.ValueForExpr(path[0].(ast.Expr)); v != nil {
return v, addr, nil
}
return nil, false, fmt.Errorf("can't locate SSA Value for expression in %s", fn)
}
// FindQueryMethods locates all methods in the given package (assumed to be
// package database/sql) with a string parameter named "query".
func FindQueryMethods(sql *types.Package, ssa *ssa.Program) []*QueryMethod {
methods := make([]*QueryMethod, 0)
scope := sql.Scope()
for _, name := range scope.Names() {
o := scope.Lookup(name)
if !o.Exported() {
continue
}
if _, ok := o.(*types.TypeName); !ok {
continue
}
n := o.Type().(*types.Named)
for i := 0; i < n.NumMethods(); i++ {
m := n.Method(i)
if !m.Exported() {
continue
}
s := m.Type().(*types.Signature)
if num, ok := FuncHasQuery(s); ok {
methods = append(methods, &QueryMethod{
Func: m,
SSA: ssa.FuncValue(m),
ArgCount: s.Params().Len(),
Param: num,
})
}
}
}
return methods
}
func checkFuncValue(t *testing.T, prog *ssa.Program, obj *types.Func) {
fn := prog.FuncValue(obj)
// fmt.Printf("FuncValue(%s) = %s\n", obj, fn) // debugging
if fn == nil {
if obj.Name() != "interfaceMethod" {
t.Errorf("FuncValue(%s) == nil", obj)
}
return
}
if fnobj := fn.Object(); fnobj != obj {
t.Errorf("FuncValue(%s).Object() == %s; value was %s",
obj, fnobj, fn.Name())
return
}
if !types.Identical(fn.Type(), obj.Type()) {
t.Errorf("FuncValue(%s).Type() == %s", obj, fn.Type())
return
}
}
func checkConstValue(t *testing.T, prog *ssa.Program, obj *types.Const) {
c := prog.ConstValue(obj)
// fmt.Printf("ConstValue(%s) = %s\n", obj, c) // debugging
if c == nil {
t.Errorf("ConstValue(%s) == nil", obj)
return
}
if !types.Identical(c.Type(), obj.Type()) {
t.Errorf("ConstValue(%s).Type() == %s", obj, c.Type())
return
}
if obj.Name() != "nil" {
if !exact.Compare(c.Value, token.EQL, obj.Val()) {
t.Errorf("ConstValue(%s).Value (%s) != %s",
obj, c.Value, obj.Val())
return
}
}
}
// findVisibleConsts returns a mapping from each package-level constant assignable to type "error", to nil.
func findVisibleConsts(prog *ssa.Program, qpos *queryPos) map[ssa.Const]*ssa.NamedConst {
constants := make(map[ssa.Const]*ssa.NamedConst)
for _, pkg := range prog.AllPackages() {
for _, mem := range pkg.Members {
obj, ok := mem.(*ssa.NamedConst)
if !ok {
continue
}
consttype := obj.Type()
if !types.AssignableTo(consttype, builtinErrorType) {
continue
}
if !isAccessibleFrom(obj.Object(), qpos.info.Pkg) {
continue
}
constants[*obj.Value] = obj
}
}
return constants
}
// findVisibleErrs returns a mapping from each package-level variable of type "error" to nil.
func findVisibleErrs(prog *ssa.Program, qpos *queryPos) map[*ssa.Global]ssa.Value {
globals := make(map[*ssa.Global]ssa.Value)
for _, pkg := range prog.AllPackages() {
for _, mem := range pkg.Members {
gbl, ok := mem.(*ssa.Global)
if !ok {
continue
}
gbltype := gbl.Type()
// globals are always pointers
if !types.Identical(deref(gbltype), builtinErrorType) {
continue
}
if !isAccessibleFrom(gbl.Object(), qpos.info.Pkg) {
continue
}
globals[gbl] = nil
}
}
return globals
}
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)
}
}
}
// Create a pointer.Config whose scope is the initial packages of lprog
// and their dependencies.
func setupPTA(prog *ssa.Program, lprog *loader.Program, ptaLog io.Writer, reflection bool) (*pointer.Config, error) {
// For each initial package (specified on the command line),
// if it has a main function, analyze that,
// otherwise analyze its tests, if any.
var mains []*ssa.Package
for _, info := range lprog.InitialPackages() {
p := prog.Package(info.Pkg)
// Add package to the pointer analysis scope.
if p.Pkg.Name() == "main" && p.Func("main") != nil {
mains = append(mains, p)
} else if main := prog.CreateTestMainPackage(p); main != nil {
mains = append(mains, main)
}
}
if mains == nil {
return nil, fmt.Errorf("analysis scope has no main and no tests")
}
return &pointer.Config{
Log: ptaLog,
Reflection: reflection,
Mains: mains,
}, nil
}
// ssaValueForIdent returns the ssa.Value for the ast.Ident whose path
// to the root of the AST is path. isAddr reports whether the
// ssa.Value is the address denoted by the ast.Ident, not its value.
//
func ssaValueForIdent(prog *ssa.Program, qinfo *loader.PackageInfo, obj types.Object, path []ast.Node) (value ssa.Value, isAddr bool, err error) {
switch obj := obj.(type) {
case *types.Var:
pkg := prog.Package(qinfo.Pkg)
pkg.Build()
if v, addr := prog.VarValue(obj, pkg, path); v != nil {
return v, addr, nil
}
return nil, false, fmt.Errorf("can't locate SSA Value for var %s", obj.Name())
case *types.Func:
fn := prog.FuncValue(obj)
if fn == nil {
return nil, false, fmt.Errorf("%s is an interface method", obj)
}
// TODO(adonovan): there's no point running PTA on a *Func ident.
// Eliminate this feature.
return fn, false, nil
}
panic(obj)
}
// Returns true if unused
func checkObj(expr *ast.Ident, object types.Object, prog *loader.Program, ssaprog *ssa.Program, fset *token.FileSet) (unused bool) {
if _, ok := object.(*types.Var); !ok {
if debug {
fmt.Println("Skipping object", object)
}
return false
}
pkg, node, _ := prog.PathEnclosingInterval(expr.Pos(), expr.End())
spkg := ssaprog.Package(pkg.Pkg)
f := ssa.EnclosingFunction(spkg, node)
if f == nil {
if debug {
fmt.Printf("Unknown function %v %v %v %v\n", fset.Position(expr.Pos()), object, pkg, prog)
}
return false
}
value, _ := f.ValueForExpr(expr)
// Unwrap unops and grab the value inside
if v, ok := value.(*ssa.UnOp); ok {
if debug {
fmt.Println("Unwrapping unop")
}
value = v.X
}
if debug {
fmt.Printf("%v %v: %v %#v\n", fset.Position(expr.Pos()), expr, object, value)
}
if _, ok := value.(*ssa.Global); ok {
if debug {
fmt.Printf(" is global\n")
}
return false
}
if value == nil {
if debug {
fmt.Println("Value is nil", object)
}
return false
}
refs := value.Referrers()
if refs == nil {
if debug {
fmt.Println("Referrers is nil", object)
}
return false
}
if debug {
fmt.Printf(" (refs) %v\n", refs)
}
hasRef := false
for _, r := range *refs {
_, ok := r.(*ssa.DebugRef)
hasRef = hasRef || !ok
if debug && !ok {
fmt.Printf("%v %v: %v %v\n", fset.Position(expr.Pos()), expr, object, r)
}
}
if !hasRef {
unused = true
}
return unused
}
func findMethod(prog *ssa.Program, meth *types.Func, typ types.Type) *ssa.Function {
if meth != nil {
fmt.Fprintf(os.Stderr, " ^ finding method for type: %s pkg: %s name: %s\n", typ.String(), meth.Pkg().Name(), meth.Name())
}
return prog.LookupMethod(typ, meth.Pkg(), meth.Name())
}
func toSSA(src io.Reader, file, pkg string) (SSA, error) {
var fs []Func
var conf loader.Config
// Parse the file into a ssa file
f, _ := conf.ParseFile(file, src)
conf.CreateFromFiles("main.go", f)
p, _ := conf.Load()
buildsanity := content["ssabuild"] == true
var ssap *ssa.Program
if buildsanity {
ssap = ssautil.CreateProgram(p, ssa.SanityCheckFunctions)
} else {
ssap = ssautil.CreateProgram(p, ssa.NaiveForm)
}
// Build ssa prog to retrieve all information and the main pkg
ssap.Build()
mainpkg := ssap.Package(p.InitialPackages()[0].Pkg)
for _, m := range mainpkg.Members {
if m.Token() == token.FUNC {
f, ok := m.(*ssa.Function)
if ok {
var params []Value
for _, p := range f.Params {
v := Value{p.Name(), reflect.TypeOf(p).String()}
params = append(params, v)
}
var freevars []Value
for _, fv := range f.FreeVars {
v := Value{fv.Name(), reflect.TypeOf(fv).String()}
freevars = append(freevars, v)
}
var locals []Value
for _, l := range f.Locals {
v := Value{l.Name(), reflect.TypeOf(l).String()}
locals = append(locals, v)
}
var blocks []BB
for _, b := range f.Blocks {
var instrs []Instr
for _, i := range b.Instrs {
in := Instr{i.String(), reflect.TypeOf(i).String()}
instrs = append(instrs, in)
}
var preds []int
for _, p := range b.Preds {
preds = append(preds, p.Index)
}
var succs []int
for _, s := range b.Succs {
succs = append(succs, s.Index)
}
bb := BB{b.Index, instrs, preds, succs}
blocks = append(blocks, bb)
}
fn := Func{f.Name(), params, "par_" + f.Name(), freevars, "freevars_" + f.Name(), locals, "locals_" + f.Name(), blocks, "blocks_" + f.Name()}
fs = append(fs, fn)
}
}
}
return SSA{fs}, nil
}
