// flatten returns a list of directly contained fields in the preorder
// traversal of the type tree of t. The resulting elements are all
// scalars (basic types or pointerlike types), except for struct/array
// "identity" nodes, whose type is that of the aggregate.
//
// reflect.Value is considered pointerlike, similar to interface{}.
//
// Callers must not mutate the result.
//
func (a *analysis) flatten(t types.Type) []*fieldInfo {
fl, ok := a.flattenMemo[t]
if !ok {
switch t := t.(type) {
case *types.Named:
u := t.Underlying()
if _, ok := u.(*types.Interface); ok {
// Debuggability hack: don't remove
// the named type from interfaces as
// they're very verbose.
fl = append(fl, &fieldInfo{typ: t})
} else {
fl = a.flatten(u)
}
case *types.Basic,
*types.Signature,
*types.Chan,
*types.Map,
*types.Interface,
*types.Slice,
*types.Pointer:
fl = append(fl, &fieldInfo{typ: t})
case *types.Array:
fl = append(fl, &fieldInfo{typ: t}) // identity node
for _, fi := range a.flatten(t.Elem()) {
fl = append(fl, &fieldInfo{typ: fi.typ, op: true, tail: fi})
}
case *types.Struct:
fl = append(fl, &fieldInfo{typ: t}) // identity node
for i, n := 0, t.NumFields(); i < n; i++ {
f := t.Field(i)
for _, fi := range a.flatten(f.Type()) {
fl = append(fl, &fieldInfo{typ: fi.typ, op: f, tail: fi})
}
}
case *types.Tuple:
// No identity node: tuples are never address-taken.
for i, n := 0, t.Len(); i < n; i++ {
f := t.At(i)
for _, fi := range a.flatten(f.Type()) {
fl = append(fl, &fieldInfo{typ: fi.typ, op: i, tail: fi})
}
}
case *types.Builtin:
panic("flatten(*types.Builtin)") // not the type of any value
default:
panic(t)
}
a.flattenMemo[t] = fl
}
return fl
}
func (tm *LLVMTypeMap) Sizeof(typ types.Type) int64 {
switch typ := typ.Underlying().(type) {
case *types.Basic:
switch typ.Kind() {
case types.Int, types.Uint:
return int64(tm.target.TypeAllocSize(tm.inttype))
case types.Uintptr, types.UnsafePointer:
return int64(tm.target.PointerSize())
case types.String:
return 2 * int64(tm.target.PointerSize())
}
return types.DefaultSizeof(typ)
case *types.Array:
eltsize := tm.Sizeof(typ.Elem())
eltalign := tm.Alignof(typ.Elem())
var eltpad int64
if eltsize%eltalign != 0 {
eltpad = eltalign - (eltsize % eltalign)
}
return (eltsize + eltpad) * typ.Len()
case *types.Struct:
if typ.NumFields() == 0 {
return 0
}
fields := make([]*types.Field, int(typ.NumFields()))
for i := range fields {
fields[i] = typ.Field(i)
}
offsets := tm.Offsetsof(fields)
n := len(fields)
return offsets[n-1] + tm.Sizeof(fields[n-1].Type)
}
return int64(tm.target.PointerSize())
}
// hashFor computes the hash of t.
func (h Hasher) hashFor(t types.Type) uint32 {
// See IsIdentical for rationale.
switch t := t.(type) {
case *types.Basic:
return uint32(t.Kind())
case *types.Array:
return 9043 + 2*uint32(t.Len()) + 3*h.Hash(t.Elem())
case *types.Slice:
return 9049 + 2*h.Hash(t.Elem())
case *types.Struct:
var hash uint32 = 9059
for i, n := 0, t.NumFields(); i < n; i++ {
f := t.Field(i)
if f.Anonymous() {
hash += 8861
}
hash += hashString(t.Tag(i))
hash += hashString(f.Name()) // (ignore f.Pkg)
hash += h.Hash(f.Type())
}
return hash
case *types.Pointer:
return 9067 + 2*h.Hash(t.Elem())
case *types.Signature:
var hash uint32 = 9091
if t.IsVariadic() {
hash *= 8863
}
return hash + 3*h.hashTuple(t.Params()) + 5*h.hashTuple(t.Results())
case *types.Interface:
var hash uint32 = 9103
for i, n := 0, t.NumMethods(); i < n; i++ {
// See go/types.identicalMethods for rationale.
// Method order is not significant.
// Ignore m.Pkg().
m := t.Method(i)
hash += 3*hashString(m.Name()) + 5*h.Hash(m.Type())
}
return hash
case *types.Map:
return 9109 + 2*h.Hash(t.Key()) + 3*h.Hash(t.Elem())
case *types.Chan:
return 9127 + 2*uint32(t.Dir()) + 3*h.Hash(t.Elem())
case *types.Named:
// Not safe with a copying GC; objects may move.
return uint32(uintptr(unsafe.Pointer(t.Obj())))
}
panic("unexpected type")
}
func (tm *llvmTypeMap) Sizeof(typ types.Type) int64 {
switch typ := typ.Underlying().(type) {
case *types.Basic:
switch typ.Kind() {
case types.Int, types.Uint:
return int64(tm.target.TypeAllocSize(tm.inttype))
case types.Uintptr, types.UnsafePointer:
return int64(tm.target.PointerSize())
}
return tm.StdSizes.Sizeof(typ)
case *types.Array:
eltsize := tm.Sizeof(typ.Elem())
eltalign := tm.Alignof(typ.Elem())
var eltpad int64
if eltsize%eltalign != 0 {
eltpad = eltalign - (eltsize % eltalign)
}
return (eltsize + eltpad) * typ.Len()
case *types.Slice:
return 3 * int64(tm.target.PointerSize())
case *types.Struct:
n := typ.NumFields()
if n == 0 {
return 0
}
fields := make([]*types.Var, n)
for i := range fields {
fields[i] = typ.Field(i)
}
offsets := tm.Offsetsof(fields)
return offsets[n-1] + tm.Sizeof(fields[n-1].Type())
case *types.Interface:
return int64((2 + typ.NumMethods()) * tm.target.PointerSize())
}
return int64(tm.target.PointerSize())
}
// zero returns a new "zero" value of the specified type.
func zero(t types.Type) value {
switch t := t.(type) {
case *types.Basic:
if t.Kind() == types.UntypedNil {
panic("untyped nil has no zero value")
}
if t.Info()&types.IsUntyped != 0 {
// TODO(adonovan): make it an invariant that
// this is unreachable. Currently some
// constants have 'untyped' types when they
// should be defaulted by the typechecker.
t = ssa.DefaultType(t).(*types.Basic)
}
switch t.Kind() {
case types.Bool:
return false
case types.Int:
return int(0)
case types.Int8:
return int8(0)
case types.Int16:
return int16(0)
case types.Int32:
return int32(0)
case types.Int64:
return int64(0)
case types.Uint:
return uint(0)
case types.Uint8:
return uint8(0)
case types.Uint16:
return uint16(0)
case types.Uint32:
return uint32(0)
case types.Uint64:
return uint64(0)
case types.Uintptr:
return uintptr(0)
case types.Float32:
return float32(0)
case types.Float64:
return float64(0)
case types.Complex64:
return complex64(0)
case types.Complex128:
return complex128(0)
case types.String:
return ""
case types.UnsafePointer:
return unsafe.Pointer(nil)
default:
panic(fmt.Sprint("zero for unexpected type:", t))
}
case *types.Pointer:
return (*value)(nil)
case *types.Array:
a := make(array, t.Len())
for i := range a {
a[i] = zero(t.Elem())
}
return a
case *types.Named:
return zero(t.Underlying())
case *types.Interface:
return iface{} // nil type, methodset and value
case *types.Slice:
return []value(nil)
case *types.Struct:
s := make(structure, t.NumFields())
for i := range s {
s[i] = zero(t.Field(i).Type())
}
return s
case *types.Tuple:
if t.Len() == 1 {
return zero(t.At(0).Type())
}
s := make(tuple, t.Len())
for i := range s {
s[i] = zero(t.At(i).Type())
}
return s
case *types.Chan:
return chan value(nil)
case *types.Map:
if usesBuiltinMap(t.Key()) {
return map[value]value(nil)
}
return (*hashmap)(nil)
case *types.Signature:
return (*ssa.Function)(nil)
}
panic(fmt.Sprint("zero: unexpected ", t))
}
func (w *Walker) writeType(buf *bytes.Buffer, typ types.Type) {
switch typ := typ.(type) {
case *types.Basic:
s := typ.Name()
switch typ.Kind() {
case types.UnsafePointer:
s = "unsafe.Pointer"
case types.UntypedBool:
s = "ideal-bool"
case types.UntypedInt:
s = "ideal-int"
case types.UntypedRune:
// "ideal-char" for compatibility with old tool
// TODO(gri) change to "ideal-rune"
s = "ideal-char"
case types.UntypedFloat:
s = "ideal-float"
case types.UntypedComplex:
s = "ideal-complex"
case types.UntypedString:
s = "ideal-string"
case types.UntypedNil:
panic("should never see untyped nil type")
default:
switch s {
case "byte":
s = "uint8"
case "rune":
s = "int32"
}
}
buf.WriteString(s)
case *types.Array:
fmt.Fprintf(buf, "[%d]", typ.Len())
w.writeType(buf, typ.Elem())
case *types.Slice:
buf.WriteString("[]")
w.writeType(buf, typ.Elem())
case *types.Struct:
buf.WriteString("struct")
case *types.Pointer:
buf.WriteByte('*')
w.writeType(buf, typ.Elem())
case *types.Tuple:
panic("should never see a tuple type")
case *types.Signature:
buf.WriteString("func")
w.writeSignature(buf, typ)
case *types.Interface:
buf.WriteString("interface{")
if typ.NumMethods() > 0 {
buf.WriteByte(' ')
buf.WriteString(strings.Join(sortedMethodNames(typ), ", "))
buf.WriteByte(' ')
}
buf.WriteString("}")
case *types.Map:
buf.WriteString("map[")
w.writeType(buf, typ.Key())
buf.WriteByte(']')
w.writeType(buf, typ.Elem())
case *types.Chan:
var s string
switch typ.Dir() {
case ast.SEND:
s = "chan<- "
case ast.RECV:
s = "<-chan "
default:
s = "chan "
}
buf.WriteString(s)
w.writeType(buf, typ.Elem())
case *types.Named:
obj := typ.Obj()
pkg := obj.Pkg()
if pkg != nil && pkg != w.current {
buf.WriteString(pkg.Name())
buf.WriteByte('.')
}
buf.WriteString(typ.Obj().Name())
default:
panic(fmt.Sprintf("unknown type %T", typ))
}
}
func (f *Finder) extract(tuple types.Type, i int) types.Type {
if tuple, ok := tuple.(*types.Tuple); ok && i < tuple.Len() {
return tuple.At(i).Type()
}
return tInvalid
}
// flatten returns a list of directly contained fields in the preorder
// traversal of the type tree of t. The resulting elements are all
// scalars (basic types or pointerlike types), except for struct/array
// "identity" nodes, whose type is that of the aggregate.
//
// reflect.Value is considered pointerlike, similar to interface{}.
//
// Callers must not mutate the result.
//
func (a *analysis) flatten(t types.Type) []*fieldInfo {
fl, ok := a.flattenMemo[t]
if !ok {
switch t := t.(type) {
case *types.Named:
u := t.Underlying()
if isInterface(u) {
// Debuggability hack: don't remove
// the named type from interfaces as
// they're very verbose.
fl = append(fl, &fieldInfo{typ: t})
} else {
fl = a.flatten(u)
}
case *types.Basic,
*types.Signature,
*types.Chan,
*types.Map,
*types.Interface,
*types.Slice,
*types.Pointer:
fl = append(fl, &fieldInfo{typ: t})
case *types.Array:
fl = append(fl, &fieldInfo{typ: t}) // identity node
for _, fi := range a.flatten(t.Elem()) {
fl = append(fl, &fieldInfo{typ: fi.typ, op: true, tail: fi})
}
case *types.Struct:
fl = append(fl, &fieldInfo{typ: t}) // identity node
for i, n := 0, t.NumFields(); i < n; i++ {
f := t.Field(i)
for _, fi := range a.flatten(f.Type()) {
fl = append(fl, &fieldInfo{typ: fi.typ, op: f, tail: fi})
}
}
case *types.Tuple:
// No identity node: tuples are never address-taken.
n := t.Len()
if n == 1 {
// Don't add a fieldInfo link for singletons,
// e.g. in params/results.
fl = append(fl, a.flatten(t.At(0).Type())...)
} else {
for i := 0; i < n; i++ {
f := t.At(i)
for _, fi := range a.flatten(f.Type()) {
fl = append(fl, &fieldInfo{typ: fi.typ, op: i, tail: fi})
}
}
}
default:
panic(t)
}
a.flattenMemo[t] = fl
}
return fl
}
