func (loc *AddrLocationSpec) Find(d *Debugger, scope *proc.EvalScope, locStr string) ([]api.Location, error) {
if scope == nil {
addr, err := strconv.ParseInt(loc.AddrExpr, 0, 64)
if err != nil {
return nil, fmt.Errorf("could not determine current location (scope is nil)")
}
return []api.Location{{PC: uint64(addr)}}, nil
} else {
v, err := scope.EvalExpression(loc.AddrExpr)
if err != nil {
return nil, err
}
if v.Unreadable != nil {
return nil, v.Unreadable
}
switch v.Kind {
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
addr, _ := constant.Uint64Val(v.Value)
return []api.Location{{PC: addr}}, nil
case reflect.Func:
pc, err := d.process.FunctionEntryToFirstLine(uint64(v.Base))
if err != nil {
return nil, err
}
return []api.Location{{PC: uint64(pc)}}, nil
default:
return nil, fmt.Errorf("wrong expression kind: %v", v.Kind)
}
}
}
// goVal returns the Go value for val, or nil.
func goVal(val constant.Value) interface{} {
// val should exist, but be conservative and check
if val == nil {
return nil
}
// Match implementation restriction of other compilers.
// gc only checks duplicates for integer, floating-point
// and string values, so only create Go values for these
// types.
switch val.Kind() {
case constant.Int:
if x, ok := constant.Int64Val(val); ok {
return x
}
if x, ok := constant.Uint64Val(val); ok {
return x
}
case constant.Float:
if x, ok := constant.Float64Val(val); ok {
return x
}
case constant.String:
return constant.StringVal(val)
}
return nil
}
func (v *Variable) setValue(y *Variable) error {
var err error
switch v.Kind {
case reflect.Float32, reflect.Float64:
f, _ := constant.Float64Val(y.Value)
err = v.writeFloatRaw(f, v.RealType.Size())
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
n, _ := constant.Int64Val(y.Value)
err = v.writeUint(uint64(n), v.RealType.Size())
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
n, _ := constant.Uint64Val(y.Value)
err = v.writeUint(n, v.RealType.Size())
case reflect.Bool:
err = v.writeBool(constant.BoolVal(y.Value))
case reflect.Complex64, reflect.Complex128:
real, _ := constant.Float64Val(constant.Real(y.Value))
imag, _ := constant.Float64Val(constant.Imag(y.Value))
err = v.writeComplex(real, imag, v.RealType.Size())
default:
fmt.Printf("default\n")
if t, isptr := v.RealType.(*dwarf.PtrType); isptr {
err = v.writeUint(uint64(y.Children[0].Addr), int64(t.ByteSize))
} else {
return fmt.Errorf("can not set variables of type %s (not implemented)", v.Kind.String())
}
}
return err
}
// Uint64 returns the numeric value of this constant truncated to fit
// an unsigned 64-bit integer.
//
func (c *Const) Uint64() uint64 {
switch x := c.Value; x.Kind() {
case exact.Int:
if u, ok := exact.Uint64Val(x); ok {
return u
}
return 0
case exact.Float:
f, _ := exact.Float64Val(x)
return uint64(f)
}
panic(fmt.Sprintf("unexpected constant value: %T", c.Value))
}
func constantBinaryOp(op token.Token, x, y constant.Value) (r constant.Value, err error) {
defer func() {
if ierr := recover(); ierr != nil {
err = fmt.Errorf("%v", ierr)
}
}()
switch op {
case token.SHL, token.SHR:
n, _ := constant.Uint64Val(y)
r = constant.Shift(x, op, uint(n))
default:
r = constant.BinaryOp(x, op, y)
}
return
}
func (v *Variable) asUint() (uint64, error) {
if v.DwarfType == nil {
if v.Value.Kind() != constant.Int {
return 0, fmt.Errorf("can not convert constant %s to uint", v.Value)
}
} else {
v.loadValue()
if v.Unreadable != nil {
return 0, v.Unreadable
}
if _, ok := v.DwarfType.(*dwarf.UintType); !ok {
return 0, fmt.Errorf("can not convert value of type %s to uint", v.DwarfType.String())
}
}
n, _ := constant.Uint64Val(v.Value)
return n, nil
}
func (filter *ScenarioFilterBasedOnTags) evaluateExp(tagExpression string) (bool, error) {
tre := regexp.MustCompile("true")
fre := regexp.MustCompile("false")
s := fre.ReplaceAllString(tre.ReplaceAllString(tagExpression, "1"), "0")
val, err := types.Eval(token.NewFileSet(), nil, 0, s)
if err != nil {
return false, errors.New("Invalid Expression.\n" + err.Error())
}
res, _ := constant.Uint64Val(val.Value)
var final bool
if res == 1 {
final = true
} else {
final = false
}
return final, nil
}
// genDecl processes one declaration clause.
func (f *File) genDecl(node ast.Node) bool {
decl, ok := node.(*ast.GenDecl)
if !ok || decl.Tok != token.CONST {
// We only care about const declarations.
return true
}
// The name of the type of the constants we are declaring.
// Can change if this is a multi-element declaration.
typ := ""
// Loop over the elements of the declaration. Each element is a ValueSpec:
// a list of names possibly followed by a type, possibly followed by values.
// If the type and value are both missing, we carry down the type (and value,
// but the "go/types" package takes care of that).
for _, spec := range decl.Specs {
vspec := spec.(*ast.ValueSpec) // Guaranteed to succeed as this is CONST.
if vspec.Type == nil && len(vspec.Values) > 0 {
// "X = 1". With no type but a value, the constant is untyped.
// Skip this vspec and reset the remembered type.
typ = ""
continue
}
if vspec.Type != nil {
// "X T". We have a type. Remember it.
ident, ok := vspec.Type.(*ast.Ident)
if !ok {
continue
}
typ = ident.Name
}
if typ != f.typeName {
// This is not the type we're looking for.
continue
}
// We now have a list of names (from one line of source code) all being
// declared with the desired type.
// Grab their names and actual values and store them in f.values.
for _, name := range vspec.Names {
if name.Name == "_" {
continue
}
// This dance lets the type checker find the values for us. It's a
// bit tricky: look up the object declared by the name, find its
// types.Const, and extract its value.
obj, ok := f.pkg.defs[name]
if !ok {
log.Fatalf("no value for constant %s", name)
}
info := obj.Type().Underlying().(*types.Basic).Info()
if info&types.IsInteger == 0 {
log.Fatalf("can't handle non-integer constant type %s", typ)
}
value := obj.(*types.Const).Val() // Guaranteed to succeed as this is CONST.
if value.Kind() != exact.Int {
log.Fatalf("can't happen: constant is not an integer %s", name)
}
i64, isInt := exact.Int64Val(value)
u64, isUint := exact.Uint64Val(value)
if !isInt && !isUint {
log.Fatalf("internal error: value of %s is not an integer: %s", name, value.String())
}
if !isInt {
u64 = uint64(i64)
}
v := Value{
name: name.Name,
value: u64,
signed: info&types.IsUnsigned == 0,
str: value.String(),
}
f.values = append(f.values, v)
}
}
return false
}
func (c *funcContext) translateExpr(expr ast.Expr) *expression {
exprType := c.p.TypeOf(expr)
if value := c.p.Types[expr].Value; value != nil {
basic := exprType.Underlying().(*types.Basic)
switch {
case isBoolean(basic):
return c.formatExpr("%s", strconv.FormatBool(constant.BoolVal(value)))
case isInteger(basic):
if is64Bit(basic) {
if basic.Kind() == types.Int64 {
d, ok := constant.Int64Val(constant.ToInt(value))
if !ok {
panic("could not get exact uint")
}
return c.formatExpr("new %s(%s, %s)", c.typeName(exprType), strconv.FormatInt(d>>32, 10), strconv.FormatUint(uint64(d)&(1<<32-1), 10))
}
d, ok := constant.Uint64Val(constant.ToInt(value))
if !ok {
panic("could not get exact uint")
}
return c.formatExpr("new %s(%s, %s)", c.typeName(exprType), strconv.FormatUint(d>>32, 10), strconv.FormatUint(d&(1<<32-1), 10))
}
d, ok := constant.Int64Val(constant.ToInt(value))
if !ok {
panic("could not get exact int")
}
return c.formatExpr("%s", strconv.FormatInt(d, 10))
case isFloat(basic):
f, _ := constant.Float64Val(value)
return c.formatExpr("%s", strconv.FormatFloat(f, 'g', -1, 64))
case isComplex(basic):
r, _ := constant.Float64Val(constant.Real(value))
i, _ := constant.Float64Val(constant.Imag(value))
if basic.Kind() == types.UntypedComplex {
exprType = types.Typ[types.Complex128]
}
return c.formatExpr("new %s(%s, %s)", c.typeName(exprType), strconv.FormatFloat(r, 'g', -1, 64), strconv.FormatFloat(i, 'g', -1, 64))
case isString(basic):
return c.formatExpr("%s", encodeString(constant.StringVal(value)))
default:
panic("Unhandled constant type: " + basic.String())
}
}
var obj types.Object
switch e := expr.(type) {
case *ast.SelectorExpr:
obj = c.p.Uses[e.Sel]
case *ast.Ident:
obj = c.p.Defs[e]
if obj == nil {
obj = c.p.Uses[e]
}
}
if obj != nil && typesutil.IsJsPackage(obj.Pkg()) {
switch obj.Name() {
case "Global":
return c.formatExpr("$global")
case "Module":
return c.formatExpr("$module")
case "Undefined":
return c.formatExpr("undefined")
}
}
switch e := expr.(type) {
case *ast.CompositeLit:
if ptrType, isPointer := exprType.(*types.Pointer); isPointer {
exprType = ptrType.Elem()
}
collectIndexedElements := func(elementType types.Type) []string {
var elements []string
i := 0
zero := c.translateExpr(c.zeroValue(elementType)).String()
for _, element := range e.Elts {
if kve, isKve := element.(*ast.KeyValueExpr); isKve {
key, ok := constant.Int64Val(constant.ToInt(c.p.Types[kve.Key].Value))
if !ok {
panic("could not get exact int")
}
i = int(key)
element = kve.Value
}
for len(elements) <= i {
elements = append(elements, zero)
}
elements[i] = c.translateImplicitConversionWithCloning(element, elementType).String()
i++
}
return elements
}
switch t := exprType.Underlying().(type) {
case *types.Array:
elements := collectIndexedElements(t.Elem())
if len(elements) == 0 {
return c.formatExpr("%s.zero()", c.typeName(t))
}
zero := c.translateExpr(c.zeroValue(t.Elem())).String()
for len(elements) < int(t.Len()) {
elements = append(elements, zero)
}
return c.formatExpr(`$toNativeArray(%s, [%s])`, typeKind(t.Elem()), strings.Join(elements, ", "))
case *types.Slice:
return c.formatExpr("new %s([%s])", c.typeName(exprType), strings.Join(collectIndexedElements(t.Elem()), ", "))
case *types.Map:
entries := make([]string, len(e.Elts))
for i, element := range e.Elts {
kve := element.(*ast.KeyValueExpr)
entries[i] = fmt.Sprintf("{ k: %s, v: %s }", c.translateImplicitConversionWithCloning(kve.Key, t.Key()), c.translateImplicitConversionWithCloning(kve.Value, t.Elem()))
}
return c.formatExpr("$makeMap(%s.keyFor, [%s])", c.typeName(t.Key()), strings.Join(entries, ", "))
case *types.Struct:
elements := make([]string, t.NumFields())
isKeyValue := true
if len(e.Elts) != 0 {
_, isKeyValue = e.Elts[0].(*ast.KeyValueExpr)
}
if !isKeyValue {
for i, element := range e.Elts {
elements[i] = c.translateImplicitConversionWithCloning(element, t.Field(i).Type()).String()
}
}
if isKeyValue {
for i := range elements {
elements[i] = c.translateExpr(c.zeroValue(t.Field(i).Type())).String()
}
for _, element := range e.Elts {
kve := element.(*ast.KeyValueExpr)
for j := range elements {
if kve.Key.(*ast.Ident).Name == t.Field(j).Name() {
elements[j] = c.translateImplicitConversionWithCloning(kve.Value, t.Field(j).Type()).String()
break
}
}
}
}
return c.formatExpr("new %s.ptr(%s)", c.typeName(exprType), strings.Join(elements, ", "))
default:
panic(fmt.Sprintf("Unhandled CompositeLit type: %T\n", t))
}
case *ast.FuncLit:
_, fun := translateFunction(e.Type, nil, e.Body, c, exprType.(*types.Signature), c.p.FuncLitInfos[e], "")
if len(c.p.escapingVars) != 0 {
names := make([]string, 0, len(c.p.escapingVars))
for obj := range c.p.escapingVars {
names = append(names, c.p.objectNames[obj])
}
sort.Strings(names)
list := strings.Join(names, ", ")
return c.formatExpr("(function(%s) { return %s; })(%s)", list, fun, list)
}
return c.formatExpr("(%s)", fun)
case *ast.UnaryExpr:
t := c.p.TypeOf(e.X)
switch e.Op {
case token.AND:
if typesutil.IsJsObject(exprType) {
return c.formatExpr("%e.object", e.X)
}
switch t.Underlying().(type) {
case *types.Struct, *types.Array:
return c.translateExpr(e.X)
}
switch x := astutil.RemoveParens(e.X).(type) {
case *ast.CompositeLit:
return c.formatExpr("$newDataPointer(%e, %s)", x, c.typeName(c.p.TypeOf(e)))
case *ast.Ident:
obj := c.p.Uses[x].(*types.Var)
if c.p.escapingVars[obj] {
return c.formatExpr("(%1s.$ptr || (%1s.$ptr = new %2s(function() { return this.$target[0]; }, function($v) { this.$target[0] = $v; }, %1s)))", c.p.objectNames[obj], c.typeName(exprType))
}
return c.formatExpr(`(%1s || (%1s = new %2s(function() { return %3s; }, function($v) { %4s })))`, c.varPtrName(obj), c.typeName(exprType), c.objectName(obj), c.translateAssign(x, c.newIdent("$v", exprType), false))
case *ast.SelectorExpr:
sel, ok := c.p.SelectionOf(x)
if !ok {
// qualified identifier
obj := c.p.Uses[x.Sel].(*types.Var)
return c.formatExpr(`(%1s || (%1s = new %2s(function() { return %3s; }, function($v) { %4s })))`, c.varPtrName(obj), c.typeName(exprType), c.objectName(obj), c.translateAssign(x, c.newIdent("$v", exprType), false))
}
newSel := &ast.SelectorExpr{X: c.newIdent("this.$target", c.p.TypeOf(x.X)), Sel: x.Sel}
c.setType(newSel, exprType)
c.p.additionalSelections[newSel] = sel
return c.formatExpr("(%1e.$ptr_%2s || (%1e.$ptr_%2s = new %3s(function() { return %4e; }, function($v) { %5s }, %1e)))", x.X, x.Sel.Name, c.typeName(exprType), newSel, c.translateAssign(newSel, c.newIdent("$v", exprType), false))
case *ast.IndexExpr:
if _, ok := c.p.TypeOf(x.X).Underlying().(*types.Slice); ok {
return c.formatExpr("$indexPtr(%1e.$array, %1e.$offset + %2e, %3s)", x.X, x.Index, c.typeName(exprType))
}
return c.formatExpr("$indexPtr(%e, %e, %s)", x.X, x.Index, c.typeName(exprType))
case *ast.StarExpr:
return c.translateExpr(x.X)
default:
panic(fmt.Sprintf("Unhandled: %T\n", x))
}
case token.ARROW:
call := &ast.CallExpr{
Fun: c.newIdent("$recv", types.NewSignature(nil, types.NewTuple(types.NewVar(0, nil, "", t)), types.NewTuple(types.NewVar(0, nil, "", exprType), types.NewVar(0, nil, "", types.Typ[types.Bool])), false)),
Args: []ast.Expr{e.X},
}
c.Blocking[call] = true
if _, isTuple := exprType.(*types.Tuple); isTuple {
return c.formatExpr("%e", call)
}
return c.formatExpr("%e[0]", call)
}
basic := t.Underlying().(*types.Basic)
switch e.Op {
case token.ADD:
return c.translateExpr(e.X)
case token.SUB:
switch {
case is64Bit(basic):
return c.formatExpr("new %1s(-%2h, -%2l)", c.typeName(t), e.X)
case isComplex(basic):
return c.formatExpr("new %1s(-%2r, -%2i)", c.typeName(t), e.X)
case isUnsigned(basic):
return c.fixNumber(c.formatExpr("-%e", e.X), basic)
default:
return c.formatExpr("-%e", e.X)
}
case token.XOR:
if is64Bit(basic) {
return c.formatExpr("new %1s(~%2h, ~%2l >>> 0)", c.typeName(t), e.X)
}
return c.fixNumber(c.formatExpr("~%e", e.X), basic)
case token.NOT:
return c.formatExpr("!%e", e.X)
default:
panic(e.Op)
}
case *ast.BinaryExpr:
if e.Op == token.NEQ {
return c.formatExpr("!(%s)", c.translateExpr(&ast.BinaryExpr{
X: e.X,
Op: token.EQL,
Y: e.Y,
}))
}
t := c.p.TypeOf(e.X)
t2 := c.p.TypeOf(e.Y)
_, isInterface := t2.Underlying().(*types.Interface)
if isInterface || types.Identical(t, types.Typ[types.UntypedNil]) {
t = t2
}
if basic, isBasic := t.Underlying().(*types.Basic); isBasic && isNumeric(basic) {
if is64Bit(basic) {
switch e.Op {
case token.MUL:
return c.formatExpr("$mul64(%e, %e)", e.X, e.Y)
case token.QUO:
return c.formatExpr("$div64(%e, %e, false)", e.X, e.Y)
case token.REM:
return c.formatExpr("$div64(%e, %e, true)", e.X, e.Y)
case token.SHL:
return c.formatExpr("$shiftLeft64(%e, %f)", e.X, e.Y)
case token.SHR:
return c.formatExpr("$shiftRight%s(%e, %f)", toJavaScriptType(basic), e.X, e.Y)
case token.EQL:
return c.formatExpr("(%1h === %2h && %1l === %2l)", e.X, e.Y)
case token.LSS:
return c.formatExpr("(%1h < %2h || (%1h === %2h && %1l < %2l))", e.X, e.Y)
case token.LEQ:
return c.formatExpr("(%1h < %2h || (%1h === %2h && %1l <= %2l))", e.X, e.Y)
case token.GTR:
return c.formatExpr("(%1h > %2h || (%1h === %2h && %1l > %2l))", e.X, e.Y)
case token.GEQ:
return c.formatExpr("(%1h > %2h || (%1h === %2h && %1l >= %2l))", e.X, e.Y)
case token.ADD, token.SUB:
return c.formatExpr("new %3s(%1h %4t %2h, %1l %4t %2l)", e.X, e.Y, c.typeName(t), e.Op)
case token.AND, token.OR, token.XOR:
return c.formatExpr("new %3s(%1h %4t %2h, (%1l %4t %2l) >>> 0)", e.X, e.Y, c.typeName(t), e.Op)
case token.AND_NOT:
return c.formatExpr("new %3s(%1h & ~%2h, (%1l & ~%2l) >>> 0)", e.X, e.Y, c.typeName(t))
default:
panic(e.Op)
}
}
if isComplex(basic) {
switch e.Op {
case token.EQL:
return c.formatExpr("(%1r === %2r && %1i === %2i)", e.X, e.Y)
case token.ADD, token.SUB:
return c.formatExpr("new %3s(%1r %4t %2r, %1i %4t %2i)", e.X, e.Y, c.typeName(t), e.Op)
case token.MUL:
return c.formatExpr("new %3s(%1r * %2r - %1i * %2i, %1r * %2i + %1i * %2r)", e.X, e.Y, c.typeName(t))
case token.QUO:
return c.formatExpr("$divComplex(%e, %e)", e.X, e.Y)
default:
panic(e.Op)
}
}
switch e.Op {
case token.EQL:
return c.formatParenExpr("%e === %e", e.X, e.Y)
case token.LSS, token.LEQ, token.GTR, token.GEQ:
return c.formatExpr("%e %t %e", e.X, e.Op, e.Y)
case token.ADD, token.SUB:
return c.fixNumber(c.formatExpr("%e %t %e", e.X, e.Op, e.Y), basic)
case token.MUL:
switch basic.Kind() {
case types.Int32, types.Int:
return c.formatParenExpr("$imul(%e, %e)", e.X, e.Y)
case types.Uint32, types.Uintptr:
return c.formatParenExpr("$imul(%e, %e) >>> 0", e.X, e.Y)
}
return c.fixNumber(c.formatExpr("%e * %e", e.X, e.Y), basic)
case token.QUO:
if isInteger(basic) {
// cut off decimals
shift := ">>"
if isUnsigned(basic) {
shift = ">>>"
}
return c.formatExpr(`(%1s = %2e / %3e, (%1s === %1s && %1s !== 1/0 && %1s !== -1/0) ? %1s %4s 0 : $throwRuntimeError("integer divide by zero"))`, c.newVariable("_q"), e.X, e.Y, shift)
}
if basic.Kind() == types.Float32 {
return c.fixNumber(c.formatExpr("%e / %e", e.X, e.Y), basic)
}
return c.formatExpr("%e / %e", e.X, e.Y)
case token.REM:
return c.formatExpr(`(%1s = %2e %% %3e, %1s === %1s ? %1s : $throwRuntimeError("integer divide by zero"))`, c.newVariable("_r"), e.X, e.Y)
case token.SHL, token.SHR:
op := e.Op.String()
if e.Op == token.SHR && isUnsigned(basic) {
op = ">>>"
}
if v := c.p.Types[e.Y].Value; v != nil {
i, _ := constant.Uint64Val(constant.ToInt(v))
if i >= 32 {
return c.formatExpr("0")
}
return c.fixNumber(c.formatExpr("%e %s %s", e.X, op, strconv.FormatUint(i, 10)), basic)
}
if e.Op == token.SHR && !isUnsigned(basic) {
return c.fixNumber(c.formatParenExpr("%e >> $min(%f, 31)", e.X, e.Y), basic)
}
y := c.newVariable("y")
return c.fixNumber(c.formatExpr("(%s = %f, %s < 32 ? (%e %s %s) : 0)", y, e.Y, y, e.X, op, y), basic)
case token.AND, token.OR:
if isUnsigned(basic) {
return c.formatParenExpr("(%e %t %e) >>> 0", e.X, e.Op, e.Y)
}
return c.formatParenExpr("%e %t %e", e.X, e.Op, e.Y)
case token.AND_NOT:
return c.fixNumber(c.formatParenExpr("%e & ~%e", e.X, e.Y), basic)
case token.XOR:
return c.fixNumber(c.formatParenExpr("%e ^ %e", e.X, e.Y), basic)
default:
panic(e.Op)
}
}
switch e.Op {
case token.ADD, token.LSS, token.LEQ, token.GTR, token.GEQ:
return c.formatExpr("%e %t %e", e.X, e.Op, e.Y)
case token.LAND:
if c.Blocking[e.Y] {
skipCase := c.caseCounter
c.caseCounter++
resultVar := c.newVariable("_v")
c.Printf("if (!(%s)) { %s = false; $s = %d; continue s; }", c.translateExpr(e.X), resultVar, skipCase)
c.Printf("%s = %s; case %d:", resultVar, c.translateExpr(e.Y), skipCase)
return c.formatExpr("%s", resultVar)
}
return c.formatExpr("%e && %e", e.X, e.Y)
case token.LOR:
if c.Blocking[e.Y] {
skipCase := c.caseCounter
c.caseCounter++
resultVar := c.newVariable("_v")
c.Printf("if (%s) { %s = true; $s = %d; continue s; }", c.translateExpr(e.X), resultVar, skipCase)
c.Printf("%s = %s; case %d:", resultVar, c.translateExpr(e.Y), skipCase)
return c.formatExpr("%s", resultVar)
}
return c.formatExpr("%e || %e", e.X, e.Y)
case token.EQL:
switch u := t.Underlying().(type) {
case *types.Array, *types.Struct:
return c.formatExpr("$equal(%e, %e, %s)", e.X, e.Y, c.typeName(t))
case *types.Interface:
return c.formatExpr("$interfaceIsEqual(%s, %s)", c.translateImplicitConversion(e.X, t), c.translateImplicitConversion(e.Y, t))
case *types.Pointer:
if _, ok := u.Elem().Underlying().(*types.Array); ok {
return c.formatExpr("$equal(%s, %s, %s)", c.translateImplicitConversion(e.X, t), c.translateImplicitConversion(e.Y, t), c.typeName(u.Elem()))
}
case *types.Basic:
if isBoolean(u) {
if b, ok := analysis.BoolValue(e.X, c.p.Info.Info); ok && b {
return c.translateExpr(e.Y)
}
if b, ok := analysis.BoolValue(e.Y, c.p.Info.Info); ok && b {
return c.translateExpr(e.X)
}
}
}
return c.formatExpr("%s === %s", c.translateImplicitConversion(e.X, t), c.translateImplicitConversion(e.Y, t))
default:
panic(e.Op)
}
case *ast.ParenExpr:
return c.formatParenExpr("%e", e.X)
case *ast.IndexExpr:
switch t := c.p.TypeOf(e.X).Underlying().(type) {
case *types.Array, *types.Pointer:
pattern := rangeCheck("%1e[%2f]", c.p.Types[e.Index].Value != nil, true)
if _, ok := t.(*types.Pointer); ok { // check pointer for nix (attribute getter causes a panic)
pattern = `(%1e.nilCheck, ` + pattern + `)`
}
return c.formatExpr(pattern, e.X, e.Index)
case *types.Slice:
return c.formatExpr(rangeCheck("%1e.$array[%1e.$offset + %2f]", c.p.Types[e.Index].Value != nil, false), e.X, e.Index)
case *types.Map:
if typesutil.IsJsObject(c.p.TypeOf(e.Index)) {
c.p.errList = append(c.p.errList, types.Error{Fset: c.p.fileSet, Pos: e.Index.Pos(), Msg: "cannot use js.Object as map key"})
}
key := fmt.Sprintf("%s.keyFor(%s)", c.typeName(t.Key()), c.translateImplicitConversion(e.Index, t.Key()))
if _, isTuple := exprType.(*types.Tuple); isTuple {
return c.formatExpr(`(%1s = %2e[%3s], %1s !== undefined ? [%1s.v, true] : [%4e, false])`, c.newVariable("_entry"), e.X, key, c.zeroValue(t.Elem()))
}
return c.formatExpr(`(%1s = %2e[%3s], %1s !== undefined ? %1s.v : %4e)`, c.newVariable("_entry"), e.X, key, c.zeroValue(t.Elem()))
case *types.Basic:
return c.formatExpr("%e.charCodeAt(%f)", e.X, e.Index)
default:
panic(fmt.Sprintf("Unhandled IndexExpr: %T\n", t))
}
case *ast.SliceExpr:
if b, isBasic := c.p.TypeOf(e.X).Underlying().(*types.Basic); isBasic && isString(b) {
switch {
case e.Low == nil && e.High == nil:
return c.translateExpr(e.X)
case e.Low == nil:
return c.formatExpr("%e.substring(0, %f)", e.X, e.High)
case e.High == nil:
return c.formatExpr("%e.substring(%f)", e.X, e.Low)
default:
return c.formatExpr("%e.substring(%f, %f)", e.X, e.Low, e.High)
}
}
slice := c.translateConversionToSlice(e.X, exprType)
switch {
case e.Low == nil && e.High == nil:
return c.formatExpr("%s", slice)
case e.Low == nil:
if e.Max != nil {
return c.formatExpr("$subslice(%s, 0, %f, %f)", slice, e.High, e.Max)
}
return c.formatExpr("$subslice(%s, 0, %f)", slice, e.High)
case e.High == nil:
return c.formatExpr("$subslice(%s, %f)", slice, e.Low)
default:
if e.Max != nil {
return c.formatExpr("$subslice(%s, %f, %f, %f)", slice, e.Low, e.High, e.Max)
}
return c.formatExpr("$subslice(%s, %f, %f)", slice, e.Low, e.High)
}
case *ast.SelectorExpr:
sel, ok := c.p.SelectionOf(e)
if !ok {
// qualified identifier
return c.formatExpr("%s", c.objectName(obj))
}
switch sel.Kind() {
case types.FieldVal:
fields, jsTag := c.translateSelection(sel, e.Pos())
if jsTag != "" {
if _, ok := sel.Type().(*types.Signature); ok {
return c.formatExpr("$internalize(%1e.%2s.%3s, %4s, %1e.%2s)", e.X, strings.Join(fields, "."), jsTag, c.typeName(sel.Type()))
}
return c.internalize(c.formatExpr("%e.%s.%s", e.X, strings.Join(fields, "."), jsTag), sel.Type())
}
return c.formatExpr("%e.%s", e.X, strings.Join(fields, "."))
case types.MethodVal:
return c.formatExpr(`$methodVal(%s, "%s")`, c.makeReceiver(e), sel.Obj().(*types.Func).Name())
case types.MethodExpr:
if !sel.Obj().Exported() {
c.p.dependencies[sel.Obj()] = true
}
if _, ok := sel.Recv().Underlying().(*types.Interface); ok {
return c.formatExpr(`$ifaceMethodExpr("%s")`, sel.Obj().(*types.Func).Name())
}
return c.formatExpr(`$methodExpr(%s, "%s")`, c.typeName(sel.Recv()), sel.Obj().(*types.Func).Name())
default:
panic(fmt.Sprintf("unexpected sel.Kind(): %T", sel.Kind()))
}
case *ast.CallExpr:
plainFun := astutil.RemoveParens(e.Fun)
if astutil.IsTypeExpr(plainFun, c.p.Info.Info) {
return c.formatExpr("%s", c.translateConversion(e.Args[0], c.p.TypeOf(plainFun)))
}
sig := c.p.TypeOf(plainFun).Underlying().(*types.Signature)
switch f := plainFun.(type) {
case *ast.Ident:
obj := c.p.Uses[f]
if o, ok := obj.(*types.Builtin); ok {
return c.translateBuiltin(o.Name(), sig, e.Args, e.Ellipsis.IsValid())
}
if typesutil.IsJsPackage(obj.Pkg()) && obj.Name() == "InternalObject" {
return c.translateExpr(e.Args[0])
}
return c.translateCall(e, sig, c.translateExpr(f))
case *ast.SelectorExpr:
sel, ok := c.p.SelectionOf(f)
if !ok {
// qualified identifier
obj := c.p.Uses[f.Sel]
if typesutil.IsJsPackage(obj.Pkg()) {
switch obj.Name() {
case "Debugger":
return c.formatExpr("debugger")
case "InternalObject":
return c.translateExpr(e.Args[0])
}
}
return c.translateCall(e, sig, c.translateExpr(f))
}
externalizeExpr := func(e ast.Expr) string {
t := c.p.TypeOf(e)
if types.Identical(t, types.Typ[types.UntypedNil]) {
return "null"
}
return c.externalize(c.translateExpr(e).String(), t)
}
externalizeArgs := func(args []ast.Expr) string {
s := make([]string, len(args))
for i, arg := range args {
s[i] = externalizeExpr(arg)
}
return strings.Join(s, ", ")
}
switch sel.Kind() {
case types.MethodVal:
recv := c.makeReceiver(f)
declaredFuncRecv := sel.Obj().(*types.Func).Type().(*types.Signature).Recv().Type()
if typesutil.IsJsObject(declaredFuncRecv) {
globalRef := func(id string) string {
if recv.String() == "$global" && id[0] == '$' && len(id) > 1 {
return id
}
return recv.String() + "." + id
}
switch sel.Obj().Name() {
case "Get":
if id, ok := c.identifierConstant(e.Args[0]); ok {
return c.formatExpr("%s", globalRef(id))
}
return c.formatExpr("%s[$externalize(%e, $String)]", recv, e.Args[0])
case "Set":
if id, ok := c.identifierConstant(e.Args[0]); ok {
return c.formatExpr("%s = %s", globalRef(id), externalizeExpr(e.Args[1]))
}
return c.formatExpr("%s[$externalize(%e, $String)] = %s", recv, e.Args[0], externalizeExpr(e.Args[1]))
case "Delete":
return c.formatExpr("delete %s[$externalize(%e, $String)]", recv, e.Args[0])
case "Length":
return c.formatExpr("$parseInt(%s.length)", recv)
case "Index":
return c.formatExpr("%s[%e]", recv, e.Args[0])
case "SetIndex":
return c.formatExpr("%s[%e] = %s", recv, e.Args[0], externalizeExpr(e.Args[1]))
case "Call":
if id, ok := c.identifierConstant(e.Args[0]); ok {
if e.Ellipsis.IsValid() {
objVar := c.newVariable("obj")
return c.formatExpr("(%s = %s, %s.%s.apply(%s, %s))", objVar, recv, objVar, id, objVar, externalizeExpr(e.Args[1]))
}
return c.formatExpr("%s(%s)", globalRef(id), externalizeArgs(e.Args[1:]))
}
if e.Ellipsis.IsValid() {
objVar := c.newVariable("obj")
return c.formatExpr("(%s = %s, %s[$externalize(%e, $String)].apply(%s, %s))", objVar, recv, objVar, e.Args[0], objVar, externalizeExpr(e.Args[1]))
}
return c.formatExpr("%s[$externalize(%e, $String)](%s)", recv, e.Args[0], externalizeArgs(e.Args[1:]))
case "Invoke":
if e.Ellipsis.IsValid() {
return c.formatExpr("%s.apply(undefined, %s)", recv, externalizeExpr(e.Args[0]))
}
return c.formatExpr("%s(%s)", recv, externalizeArgs(e.Args))
case "New":
if e.Ellipsis.IsValid() {
return c.formatExpr("new ($global.Function.prototype.bind.apply(%s, [undefined].concat(%s)))", recv, externalizeExpr(e.Args[0]))
}
return c.formatExpr("new (%s)(%s)", recv, externalizeArgs(e.Args))
case "Bool":
return c.internalize(recv, types.Typ[types.Bool])
case "String":
return c.internalize(recv, types.Typ[types.String])
case "Int":
return c.internalize(recv, types.Typ[types.Int])
case "Int64":
return c.internalize(recv, types.Typ[types.Int64])
case "Uint64":
return c.internalize(recv, types.Typ[types.Uint64])
case "Float":
return c.internalize(recv, types.Typ[types.Float64])
case "Interface":
return c.internalize(recv, types.NewInterface(nil, nil))
case "Unsafe":
return recv
default:
panic("Invalid js package object: " + sel.Obj().Name())
}
}
methodName := sel.Obj().Name()
if reservedKeywords[methodName] {
methodName += "$"
}
return c.translateCall(e, sig, c.formatExpr("%s.%s", recv, methodName))
case types.FieldVal:
fields, jsTag := c.translateSelection(sel, f.Pos())
if jsTag != "" {
call := c.formatExpr("%e.%s.%s(%s)", f.X, strings.Join(fields, "."), jsTag, externalizeArgs(e.Args))
switch sig.Results().Len() {
case 0:
return call
case 1:
return c.internalize(call, sig.Results().At(0).Type())
default:
c.p.errList = append(c.p.errList, types.Error{Fset: c.p.fileSet, Pos: f.Pos(), Msg: "field with js tag can not have func type with multiple results"})
}
}
return c.translateCall(e, sig, c.formatExpr("%e.%s", f.X, strings.Join(fields, ".")))
case types.MethodExpr:
return c.translateCall(e, sig, c.translateExpr(f))
default:
panic(fmt.Sprintf("unexpected sel.Kind(): %T", sel.Kind()))
}
default:
return c.translateCall(e, sig, c.translateExpr(plainFun))
}
case *ast.StarExpr:
if typesutil.IsJsObject(c.p.TypeOf(e.X)) {
return c.formatExpr("new $jsObjectPtr(%e)", e.X)
}
if c1, isCall := e.X.(*ast.CallExpr); isCall && len(c1.Args) == 1 {
if c2, isCall := c1.Args[0].(*ast.CallExpr); isCall && len(c2.Args) == 1 && types.Identical(c.p.TypeOf(c2.Fun), types.Typ[types.UnsafePointer]) {
if unary, isUnary := c2.Args[0].(*ast.UnaryExpr); isUnary && unary.Op == token.AND {
return c.translateExpr(unary.X) // unsafe conversion
}
}
}
switch exprType.Underlying().(type) {
case *types.Struct, *types.Array:
return c.translateExpr(e.X)
}
return c.formatExpr("%e.$get()", e.X)
case *ast.TypeAssertExpr:
if e.Type == nil {
return c.translateExpr(e.X)
}
t := c.p.TypeOf(e.Type)
if _, isTuple := exprType.(*types.Tuple); isTuple {
return c.formatExpr("$assertType(%e, %s, true)", e.X, c.typeName(t))
}
return c.formatExpr("$assertType(%e, %s)", e.X, c.typeName(t))
case *ast.Ident:
if e.Name == "_" {
panic("Tried to translate underscore identifier.")
}
switch o := obj.(type) {
case *types.Var, *types.Const:
return c.formatExpr("%s", c.objectName(o))
case *types.Func:
return c.formatExpr("%s", c.objectName(o))
case *types.TypeName:
return c.formatExpr("%s", c.typeName(o.Type()))
case *types.Nil:
if typesutil.IsJsObject(exprType) {
return c.formatExpr("null")
}
switch t := exprType.Underlying().(type) {
case *types.Basic:
if t.Kind() != types.UnsafePointer {
panic("unexpected basic type")
}
return c.formatExpr("0")
case *types.Slice, *types.Pointer:
return c.formatExpr("%s.nil", c.typeName(exprType))
case *types.Chan:
return c.formatExpr("$chanNil")
case *types.Map:
return c.formatExpr("false")
case *types.Interface:
return c.formatExpr("$ifaceNil")
case *types.Signature:
return c.formatExpr("$throwNilPointerError")
default:
panic(fmt.Sprintf("unexpected type: %T", t))
}
default:
panic(fmt.Sprintf("Unhandled object: %T\n", o))
}
case *this:
if isWrapped(c.p.TypeOf(e)) {
return c.formatExpr("this.$val")
}
return c.formatExpr("this")
case nil:
return c.formatExpr("")
default:
panic(fmt.Sprintf("Unhandled expression: %T\n", e))
}
}
func (c *funcContext) formatExprInternal(format string, a []interface{}, parens bool) *expression {
processFormat := func(f func(uint8, uint8, int)) {
n := 0
for i := 0; i < len(format); i++ {
b := format[i]
if b == '%' {
i++
k := format[i]
if k >= '0' && k <= '9' {
n = int(k - '0' - 1)
i++
k = format[i]
}
f(0, k, n)
n++
continue
}
f(b, 0, 0)
}
}
counts := make([]int, len(a))
processFormat(func(b, k uint8, n int) {
switch k {
case 'e', 'f', 'h', 'l', 'r', 'i':
counts[n]++
}
})
out := bytes.NewBuffer(nil)
vars := make([]string, len(a))
hasAssignments := false
for i, e := range a {
if counts[i] <= 1 {
continue
}
if _, isIdent := e.(*ast.Ident); isIdent {
continue
}
if val := c.p.Types[e.(ast.Expr)].Value; val != nil {
continue
}
if !hasAssignments {
hasAssignments = true
out.WriteByte('(')
parens = false
}
v := c.newVariable("x")
out.WriteString(v + " = " + c.translateExpr(e.(ast.Expr)).String() + ", ")
vars[i] = v
}
processFormat(func(b, k uint8, n int) {
writeExpr := func(suffix string) {
if vars[n] != "" {
out.WriteString(vars[n] + suffix)
return
}
out.WriteString(c.translateExpr(a[n].(ast.Expr)).StringWithParens() + suffix)
}
switch k {
case 0:
out.WriteByte(b)
case 's':
if e, ok := a[n].(*expression); ok {
out.WriteString(e.StringWithParens())
return
}
out.WriteString(a[n].(string))
case 'd':
out.WriteString(strconv.Itoa(a[n].(int)))
case 't':
out.WriteString(a[n].(token.Token).String())
case 'e':
e := a[n].(ast.Expr)
if val := c.p.Types[e].Value; val != nil {
out.WriteString(c.translateExpr(e).String())
return
}
writeExpr("")
case 'f':
e := a[n].(ast.Expr)
if val := c.p.Types[e].Value; val != nil {
d, _ := constant.Int64Val(constant.ToInt(val))
out.WriteString(strconv.FormatInt(d, 10))
return
}
if is64Bit(c.p.TypeOf(e).Underlying().(*types.Basic)) {
out.WriteString("$flatten64(")
writeExpr("")
out.WriteString(")")
return
}
writeExpr("")
case 'h':
e := a[n].(ast.Expr)
if val := c.p.Types[e].Value; val != nil {
d, _ := constant.Uint64Val(constant.ToInt(val))
if c.p.TypeOf(e).Underlying().(*types.Basic).Kind() == types.Int64 {
out.WriteString(strconv.FormatInt(int64(d)>>32, 10))
return
}
out.WriteString(strconv.FormatUint(d>>32, 10))
return
}
writeExpr(".$high")
case 'l':
if val := c.p.Types[a[n].(ast.Expr)].Value; val != nil {
d, _ := constant.Uint64Val(constant.ToInt(val))
out.WriteString(strconv.FormatUint(d&(1<<32-1), 10))
return
}
writeExpr(".$low")
case 'r':
if val := c.p.Types[a[n].(ast.Expr)].Value; val != nil {
r, _ := constant.Float64Val(constant.Real(val))
out.WriteString(strconv.FormatFloat(r, 'g', -1, 64))
return
}
writeExpr(".$real")
case 'i':
if val := c.p.Types[a[n].(ast.Expr)].Value; val != nil {
i, _ := constant.Float64Val(constant.Imag(val))
out.WriteString(strconv.FormatFloat(i, 'g', -1, 64))
return
}
writeExpr(".$imag")
case '%':
out.WriteRune('%')
default:
panic(fmt.Sprintf("formatExpr: %%%c%d", k, n))
}
})
if hasAssignments {
out.WriteByte(')')
}
return &expression{str: out.String(), parens: parens}
}
func (check *Checker) shift(x, y *operand, e *ast.BinaryExpr, op token.Token) {
untypedx := isUntyped(x.typ)
var xval constant.Value
if x.mode == constant_ {
xval = constant.ToInt(x.val)
}
if isInteger(x.typ) || untypedx && xval != nil && xval.Kind() == constant.Int {
// The lhs is of integer type or an untyped constant representable
// as an integer. Nothing to do.
} else {
// shift has no chance
check.invalidOp(x.pos(), "shifted operand %s must be integer", x)
x.mode = invalid
return
}
// spec: "The right operand in a shift expression must have unsigned
// integer type or be an untyped constant that can be converted to
// unsigned integer type."
switch {
case isUnsigned(y.typ):
// nothing to do
case isUntyped(y.typ):
check.convertUntyped(y, Typ[UntypedInt])
if y.mode == invalid {
x.mode = invalid
return
}
default:
check.invalidOp(y.pos(), "shift count %s must be unsigned integer", y)
x.mode = invalid
return
}
if x.mode == constant_ {
if y.mode == constant_ {
// rhs must be an integer value
yval := constant.ToInt(y.val)
if yval.Kind() != constant.Int {
check.invalidOp(y.pos(), "shift count %s must be unsigned integer", y)
x.mode = invalid
return
}
// rhs must be within reasonable bounds
const shiftBound = 1023 - 1 + 52 // so we can express smallestFloat64
s, ok := constant.Uint64Val(yval)
if !ok || s > shiftBound {
check.invalidOp(y.pos(), "invalid shift count %s", y)
x.mode = invalid
return
}
// The lhs is representable as an integer but may not be an integer
// (e.g., 2.0, an untyped float) - this can only happen for untyped
// non-integer numeric constants. Correct the type so that the shift
// result is of integer type.
if !isInteger(x.typ) {
x.typ = Typ[UntypedInt]
}
// x is a constant so xval != nil and it must be of Int kind.
x.val = constant.Shift(xval, op, uint(s))
// Typed constants must be representable in
// their type after each constant operation.
if isTyped(x.typ) {
if e != nil {
x.expr = e // for better error message
}
check.representable(x, x.typ.Underlying().(*Basic))
}
return
}
// non-constant shift with constant lhs
if untypedx {
// spec: "If the left operand of a non-constant shift
// expression is an untyped constant, the type of the
// constant is what it would be if the shift expression
// were replaced by its left operand alone.".
//
// Delay operand checking until we know the final type
// by marking the lhs expression as lhs shift operand.
//
// Usually (in correct programs), the lhs expression
// is in the untyped map. However, it is possible to
// create incorrect programs where the same expression
// is evaluated twice (via a declaration cycle) such
// that the lhs expression type is determined in the
// first round and thus deleted from the map, and then
// not found in the second round (double insertion of
// the same expr node still just leads to one entry for
// that node, and it can only be deleted once).
// Be cautious and check for presence of entry.
// Example: var e, f = int(1<<""[f]) // issue 11347
if info, found := check.untyped[x.expr]; found {
info.isLhs = true
check.untyped[x.expr] = info
}
// keep x's type
x.mode = value
return
}
}
// constant rhs must be >= 0
if y.mode == constant_ && constant.Sign(y.val) < 0 {
check.invalidOp(y.pos(), "shift count %s must not be negative", y)
}
// non-constant shift - lhs must be an integer
if !isInteger(x.typ) {
check.invalidOp(x.pos(), "shifted operand %s must be integer", x)
x.mode = invalid
return
}
x.mode = value
}
// Eval type cast expressions
func (scope *EvalScope) evalTypeCast(node *ast.CallExpr) (*Variable, error) {
argv, err := scope.evalAST(node.Args[0])
if err != nil {
return nil, err
}
argv.loadValue()
if argv.Unreadable != nil {
return nil, argv.Unreadable
}
fnnode := node.Fun
// remove all enclosing parenthesis from the type name
for {
p, ok := fnnode.(*ast.ParenExpr)
if !ok {
break
}
fnnode = p.X
}
styp, err := scope.Thread.dbp.findTypeExpr(fnnode)
if err != nil {
return nil, err
}
typ := resolveTypedef(styp)
converr := fmt.Errorf("can not convert %q to %s", exprToString(node.Args[0]), typ.String())
v := newVariable("", 0, styp, scope.Thread.dbp, scope.Thread)
v.loaded = true
switch ttyp := typ.(type) {
case *dwarf.PtrType:
switch argv.Kind {
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
// ok
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
// ok
default:
return nil, converr
}
n, _ := constant.Int64Val(argv.Value)
v.Children = []Variable{*(scope.newVariable("", uintptr(n), ttyp.Type))}
return v, nil
case *dwarf.UintType:
switch argv.Kind {
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
n, _ := constant.Int64Val(argv.Value)
v.Value = constant.MakeUint64(convertInt(uint64(n), false, ttyp.Size()))
return v, nil
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
n, _ := constant.Uint64Val(argv.Value)
v.Value = constant.MakeUint64(convertInt(n, false, ttyp.Size()))
return v, nil
case reflect.Float32, reflect.Float64:
x, _ := constant.Float64Val(argv.Value)
v.Value = constant.MakeUint64(uint64(x))
return v, nil
}
case *dwarf.IntType:
switch argv.Kind {
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
n, _ := constant.Int64Val(argv.Value)
v.Value = constant.MakeInt64(int64(convertInt(uint64(n), true, ttyp.Size())))
return v, nil
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
n, _ := constant.Uint64Val(argv.Value)
v.Value = constant.MakeInt64(int64(convertInt(n, true, ttyp.Size())))
return v, nil
case reflect.Float32, reflect.Float64:
x, _ := constant.Float64Val(argv.Value)
v.Value = constant.MakeInt64(int64(x))
return v, nil
}
case *dwarf.FloatType:
switch argv.Kind {
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
fallthrough
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
fallthrough
case reflect.Float32, reflect.Float64:
v.Value = argv.Value
return v, nil
}
case *dwarf.ComplexType:
switch argv.Kind {
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
fallthrough
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
fallthrough
case reflect.Float32, reflect.Float64:
v.Value = argv.Value
return v, nil
}
}
return nil, converr
}
func (check *Checker) shift(x, y *operand, op token.Token) {
untypedx := isUntyped(x.typ)
// The lhs must be of integer type or be representable
// as an integer; otherwise the shift has no chance.
if !x.isInteger() {
check.invalidOp(x.pos(), "shifted operand %s must be integer", x)
x.mode = invalid
return
}
// spec: "The right operand in a shift expression must have unsigned
// integer type or be an untyped constant that can be converted to
// unsigned integer type."
switch {
case isInteger(y.typ) && isUnsigned(y.typ):
// nothing to do
case isUntyped(y.typ):
check.convertUntyped(y, Typ[UntypedInt])
if y.mode == invalid {
x.mode = invalid
return
}
default:
check.invalidOp(y.pos(), "shift count %s must be unsigned integer", y)
x.mode = invalid
return
}
if x.mode == constant {
if y.mode == constant {
// rhs must be an integer value
if !y.isInteger() {
check.invalidOp(y.pos(), "shift count %s must be unsigned integer", y)
x.mode = invalid
return
}
// rhs must be within reasonable bounds
const stupidShift = 1023 - 1 + 52 // so we can express smallestFloat64
s, ok := exact.Uint64Val(y.val)
if !ok || s > stupidShift {
check.invalidOp(y.pos(), "stupid shift count %s", y)
x.mode = invalid
return
}
// The lhs is representable as an integer but may not be an integer
// (e.g., 2.0, an untyped float) - this can only happen for untyped
// non-integer numeric constants. Correct the type so that the shift
// result is of integer type.
if !isInteger(x.typ) {
x.typ = Typ[UntypedInt]
}
x.val = exact.Shift(x.val, op, uint(s))
return
}
// non-constant shift with constant lhs
if untypedx {
// spec: "If the left operand of a non-constant shift
// expression is an untyped constant, the type of the
// constant is what it would be if the shift expression
// were replaced by its left operand alone.".
//
// Delay operand checking until we know the final type:
// The lhs expression must be in the untyped map, mark
// the entry as lhs shift operand.
info, found := check.untyped[x.expr]
assert(found)
info.isLhs = true
check.untyped[x.expr] = info
// keep x's type
x.mode = value
return
}
}
// constant rhs must be >= 0
if y.mode == constant && exact.Sign(y.val) < 0 {
check.invalidOp(y.pos(), "shift count %s must not be negative", y)
}
// non-constant shift - lhs must be an integer
if !isInteger(x.typ) {
check.invalidOp(x.pos(), "shifted operand %s must be integer", x)
x.mode = invalid
return
}
x.mode = value
}