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mirror of https://github.com/golang/go synced 2024-11-13 19:20:31 -07:00

Cleanup of Type/Value interface. Add Type.ZeroVal, replace

all type-specific value functions, and use ZeroVal to create
new frames.  Remove Value.Type; it was unused and difficult
for values with composite types.  Add Value.Assign methods.

R=rsc
APPROVED=rsc
DELTA=282  (135 added, 90 deleted, 57 changed)
OCL=31894
CL=31930
This commit is contained in:
Austin Clements 2009-07-21 13:31:23 -07:00
parent 39808db15a
commit 90ffb7b8f5
5 changed files with 190 additions and 145 deletions

View File

@ -12,6 +12,8 @@ import (
* Types
*/
type Value interface
type Type interface {
// literal returns this type with all names recursively
// stripped.
@ -28,6 +30,8 @@ type Type interface {
isFloat() bool;
// isIdeal returns true if this is an ideal int or float.
isIdeal() bool;
// ZeroVal returns a new zero value of this type.
Zero() Value;
// String returns the string representation of this type.
String() string;
}
@ -45,9 +49,12 @@ type BoundedType interface {
*/
type Value interface {
// TODO(austin) Is Type even necessary?
Type() Type;
String() string;
// Assign copies another value into this one. It should
// assume that the other value satisfies the same specific
// value interface (BoolValue, etc.), but must not assume
// anything about its specific type.
Assign(o Value);
}
type BoolValue interface {
@ -117,7 +124,6 @@ type Variable struct {
}
type Constant struct {
// TODO(austin) Need Type?
Type Type;
Value Value;
}
@ -129,12 +135,13 @@ type Scope struct {
outer *Scope;
defs map[string] Def;
numVars int;
varTypes []Type;
}
func NewRootScope() *Scope
func (s *Scope) Fork() *Scope
func (s *Scope) DefineVar(name string, t Type) *Variable
func (s *Scope) DefineConst(name string, v Value) *Constant
func (s *Scope) DefineConst(name string, t Type, v Value) *Constant
func (s *Scope) DefineType(name string, t Type) bool
func (s *Scope) Lookup(name string) (Def, *Scope)
@ -149,3 +156,5 @@ type Frame struct {
}
func (f *Frame) Get(s *Scope, index int) Value
func (s *Scope) NewFrame(outer *Frame) *Frame

View File

@ -632,6 +632,8 @@ func (a *exprCompiler) DoBinaryExpr(x *ast.BinaryExpr) {
}
// Useful type predicates
// TODO(austin) The spec is wrong here. The types must be
// identical, not compatible.
compat := func() bool {
return l.t.compatible(r.t);
};
@ -829,9 +831,6 @@ func (a *exprCompiler) DoBinaryExpr(x *ast.BinaryExpr) {
a.genBinOpXor(l, r);
case token.AND_NOT:
if l.t.isIdeal() || r.t.isIdeal() {
log.Crashf("&^ for ideals not implemented");
}
a.genBinOpAndNot(l, r);
case token.SHL:
@ -911,11 +910,14 @@ func compileExpr(expr ast.Expr, scope *Scope, errors scanner.ErrorHandler) *expr
*/
type Expr struct {
f func(f *Frame) Value;
t Type;
f func(f *Frame, out Value);
}
func (expr *Expr) Eval(f *Frame) Value {
return expr.f(f);
v := expr.t.Zero();
expr.f(f, v);
return v;
}
func CompileExpr(expr ast.Expr, scope *Scope) (*Expr, os.Error) {
@ -925,26 +927,23 @@ func CompileExpr(expr ast.Expr, scope *Scope) (*Expr, os.Error) {
if ec == nil {
return nil, errors.GetError(scanner.Sorted);
}
// TODO(austin) This still uses Value as a generic container
// and is the only user of the 'value' methods on each type.
// Need to figure out a better way to do this.
switch t := ec.t.(type) {
case *boolType:
return &Expr{func(f *Frame) Value { return t.value(ec.evalBool(f)) }}, nil;
return &Expr{t, func(f *Frame, out Value) { out.(BoolValue).Set(ec.evalBool(f)) }}, nil;
case *uintType:
return &Expr{func(f *Frame) Value { return t.value(ec.evalUint(f)) }}, nil;
return &Expr{t, func(f *Frame, out Value) { out.(UintValue).Set(ec.evalUint(f)) }}, nil;
case *intType:
return &Expr{func(f *Frame) Value { return t.value(ec.evalInt(f)) }}, nil;
return &Expr{t, func(f *Frame, out Value) { out.(IntValue).Set(ec.evalInt(f)) }}, nil;
case *idealIntType:
return &Expr{func(f *Frame) Value { return t.value(ec.evalIdealInt()) }}, nil;
return &Expr{t, func(f *Frame, out Value) { out.(*idealIntV).V = ec.evalIdealInt() }}, nil;
case *floatType:
return &Expr{func(f *Frame) Value { return t.value(ec.evalFloat(f)) }}, nil;
return &Expr{t, func(f *Frame, out Value) { out.(FloatValue).Set(ec.evalFloat(f)) }}, nil;
case *idealFloatType:
return &Expr{func(f *Frame) Value { return t.value(ec.evalIdealFloat()) }}, nil;
return &Expr{t, func(f *Frame, out Value) { out.(*idealFloatV).V = ec.evalIdealFloat() }}, nil;
case *stringType:
return &Expr{func(f *Frame) Value { return t.value(ec.evalString(f)) }}, nil;
return &Expr{t, func(f *Frame, out Value) { out.(StringValue).Set(ec.evalString(f)) }}, nil;
case *PtrType:
return &Expr{func(f *Frame) Value { return t.value(ec.evalPtr(f)) }}, nil;
return &Expr{t, func(f *Frame, out Value) { out.(PtrValue).Set(ec.evalPtr(f)) }}, nil;
}
log.Crashf("unexpected type %v", ec.t);
panic();
@ -1282,6 +1281,11 @@ func (a *exprCompiler) genBinOpAndNot(l *exprCompiler, r *exprCompiler) {
lf := l.asInt();
rf := r.asInt();
a.evalInt = func(f *Frame) int64 { return lf(f) &^ rf(f) };
case *idealIntType:
lf := l.asIdealInt();
rf := r.asIdealInt();
val := lf().AndNot(rf());
a.evalIdealInt = func() *bignum.Integer { return val };
default:
log.Crashf("unexpected result type %v at %v", l.t.literal(), a.pos);
}

View File

@ -9,11 +9,11 @@ import (
)
func NewRootScope() *Scope {
return &Scope{nil, make(map[string] Def), 0};
return &Scope{defs: make(map[string] Def)};
}
func (s *Scope) Fork() *Scope {
return &Scope{s, make(map[string] Def), 0};
return &Scope{outer: s, defs: make(map[string] Def)};
}
func (s *Scope) DefineVar(name string, t Type) *Variable {
@ -26,11 +26,11 @@ func (s *Scope) DefineVar(name string, t Type) *Variable {
return v;
}
func (s *Scope) DefineConst(name string, v Value) *Constant {
func (s *Scope) DefineConst(name string, t Type, v Value) *Constant {
if _, ok := s.defs[name]; ok {
return nil;
}
c := &Constant{v.Type(), v};
c := &Constant{t, v};
s.defs[name] = c;
return c;
}
@ -53,6 +53,27 @@ func (s *Scope) Lookup(name string) (Def, *Scope) {
return nil, nil;
}
func (s *Scope) NewFrame(outer *Frame) *Frame {
if s.varTypes == nil {
// First creation of a frame from this scope. Compute
// and memoize the types of all variables.
ts := make([]Type, s.numVars);
for _, d := range s.defs {
if v, ok := d.(*Variable); ok {
ts[v.Index] = v.Type;
}
}
s.varTypes = ts;
}
// Create frame
vars := make([]Value, s.numVars);
for i, t := range s.varTypes {
vars[i] = t.Zero();
}
return &Frame{outer, s, vars};
}
func (f *Frame) Get(s *Scope, index int) Value {
for f.Scope != s {
f = f.Outer;

View File

@ -68,7 +68,7 @@ func (boolType) String() string {
return "bool";
}
func (t *boolType) value(v bool) BoolValue
func (t *boolType) Zero() Value
type uintType struct {
commonType;
@ -110,7 +110,7 @@ func (t *uintType) String() string {
return t.name;
}
func (t *uintType) value(v uint64) UintValue
func (t *uintType) Zero() Value
func (t *uintType) minVal() *bignum.Rational {
return bignum.Rat(0, 1);
@ -158,7 +158,7 @@ func (t *intType) String() string {
return t.name;
}
func (t *intType) value(v int64) IntValue
func (t *intType) Zero() Value
func (t *intType) minVal() *bignum.Rational {
return bignum.MakeRat(bignum.Int(-1).Shl(t.Bits - 1), bignum.Nat(1));
@ -194,7 +194,7 @@ func (t *idealIntType) String() string {
return "ideal integer";
}
func (t *idealIntType) value(v *bignum.Integer) IdealIntValue
func (t *idealIntType) Zero() Value
type floatType struct {
commonType;
@ -223,7 +223,7 @@ func (t *floatType) String() string {
return "float";
}
func (t *floatType) value(v float64) FloatValue
func (t *floatType) Zero() Value
var maxFloat32Val = bignum.MakeRat(bignum.Int(0xffffff).Shl(127-23), bignum.Nat(1));
var maxFloat64Val = bignum.MakeRat(bignum.Int(0x1fffffffffffff).Shl(1023-52), bignum.Nat(1));
@ -278,7 +278,7 @@ func (t *idealFloatType) String() string {
return "ideal float";
}
func (t *idealFloatType) value(v *bignum.Rational) IdealFloatValue
func (t *idealFloatType) Zero() Value
type stringType struct {
commonType;
@ -298,7 +298,7 @@ func (t *stringType) String() string {
return "string";
}
func (t *stringType) value(v string) StringValue
func (t *stringType) Zero() Value
type ArrayType struct {
commonType;
@ -338,7 +338,7 @@ func (t *ArrayType) String() string {
return "[]" + t.Elem.String();
}
func (t *ArrayType) value(v []Value) ArrayValue
func (t *ArrayType) Zero() Value
/*
func (t *ArrayType) literal() Type {
@ -383,7 +383,7 @@ func (t *PtrType) String() string {
return "*" + t.Elem.String();
}
func (t *PtrType) value(v Value) PtrValue
func (t *PtrType) Zero() Value
/*
type FuncType struct {

View File

@ -16,14 +16,14 @@ import (
type boolV bool
func (*boolV) Type() Type {
return BoolType;
}
func (v *boolV) String() string {
return fmt.Sprint(*v);
}
func (v *boolV) Assign(o Value) {
*v = boolV(o.(BoolValue).Get());
}
func (v *boolV) Get() bool {
return bool(*v);
}
@ -32,8 +32,8 @@ func (v *boolV) Set(x bool) {
*v = boolV(x);
}
func (t *boolType) value(v bool) BoolValue {
res := boolV(v);
func (t *boolType) Zero() Value {
res := boolV(false);
return &res;
}
@ -43,14 +43,14 @@ func (t *boolType) value(v bool) BoolValue {
type uint8V uint8
func (*uint8V) Type() Type {
return Uint8Type;
}
func (v *uint8V) String() string {
return fmt.Sprint(*v);
}
func (v *uint8V) Assign(o Value) {
*v = uint8V(o.(UintValue).Get());
}
func (v *uint8V) Get() uint64 {
return uint64(*v);
}
@ -61,14 +61,14 @@ func (v *uint8V) Set(x uint64) {
type uint16V uint16
func (*uint16V) Type() Type {
return Uint16Type;
}
func (v *uint16V) String() string {
return fmt.Sprint(*v);
}
func (v *uint16V) Assign(o Value) {
*v = uint16V(o.(UintValue).Get());
}
func (v *uint16V) Get() uint64 {
return uint64(*v);
}
@ -79,14 +79,14 @@ func (v *uint16V) Set(x uint64) {
type uint32V uint32
func (*uint32V) Type() Type {
return Uint32Type;
}
func (v *uint32V) String() string {
return fmt.Sprint(*v);
}
func (v *uint32V) Assign(o Value) {
*v = uint32V(o.(UintValue).Get());
}
func (v *uint32V) Get() uint64 {
return uint64(*v);
}
@ -97,14 +97,14 @@ func (v *uint32V) Set(x uint64) {
type uint64V uint64
func (*uint64V) Type() Type {
return Uint64Type;
}
func (v *uint64V) String() string {
return fmt.Sprint(*v);
}
func (v *uint64V) Assign(o Value) {
*v = uint64V(o.(UintValue).Get());
}
func (v *uint64V) Get() uint64 {
return uint64(*v);
}
@ -115,14 +115,14 @@ func (v *uint64V) Set(x uint64) {
type uintV uint
func (*uintV) Type() Type {
return UintType;
}
func (v *uintV) String() string {
return fmt.Sprint(*v);
}
func (v *uintV) Assign(o Value) {
*v = uintV(o.(UintValue).Get());
}
func (v *uintV) Get() uint64 {
return uint64(*v);
}
@ -133,14 +133,14 @@ func (v *uintV) Set(x uint64) {
type uintptrV uintptr
func (*uintptrV) Type() Type {
return UintptrType;
}
func (v *uintptrV) String() string {
return fmt.Sprint(*v);
}
func (v *uintptrV) Assign(o Value) {
*v = uintptrV(o.(UintValue).Get());
}
func (v *uintptrV) Get() uint64 {
return uint64(*v);
}
@ -149,29 +149,28 @@ func (v *uintptrV) Set(x uint64) {
*v = uintptrV(x);
}
func (t *uintType) value(v uint64) UintValue {
// TODO(austin) The 'value' methods are only used for
// testing right now. Get rid of them.
// TODO(austin) Deal with named types
func (t *uintType) Zero() Value {
// TODO(austin) t may be a named type instead of one of the
// base types.
switch Type(t) {
case Uint8Type:
res := uint8V(v);
res := uint8V(0);
return &res;
case Uint16Type:
res := uint16V(v);
res := uint16V(0);
return &res;
case Uint32Type:
res := uint32V(v);
res := uint32V(0);
return &res;
case Uint64Type:
res := uint64V(v);
res := uint64V(0);
return &res;
case UintType:
res := uintV(v);
res := uintV(0);
return &res;
case UintptrType:
res := uintptrV(v);
res := uintptrV(0);
return &res;
}
panic("unknown uint type ", t.String());
@ -183,14 +182,14 @@ func (t *uintType) value(v uint64) UintValue {
type int8V int8
func (*int8V) Type() Type {
return Int8Type;
}
func (v *int8V) String() string {
return fmt.Sprint(*v);
}
func (v *int8V) Assign(o Value) {
*v = int8V(o.(IntValue).Get());
}
func (v *int8V) Get() int64 {
return int64(*v);
}
@ -201,14 +200,14 @@ func (v *int8V) Set(x int64) {
type int16V int16
func (*int16V) Type() Type {
return Int16Type;
}
func (v *int16V) String() string {
return fmt.Sprint(*v);
}
func (v *int16V) Assign(o Value) {
*v = int16V(o.(IntValue).Get());
}
func (v *int16V) Get() int64 {
return int64(*v);
}
@ -219,14 +218,14 @@ func (v *int16V) Set(x int64) {
type int32V int32
func (*int32V) Type() Type {
return Int32Type;
}
func (v *int32V) String() string {
return fmt.Sprint(*v);
}
func (v *int32V) Assign(o Value) {
*v = int32V(o.(IntValue).Get());
}
func (v *int32V) Get() int64 {
return int64(*v);
}
@ -237,14 +236,14 @@ func (v *int32V) Set(x int64) {
type int64V int64
func (*int64V) Type() Type {
return Int64Type;
}
func (v *int64V) String() string {
return fmt.Sprint(*v);
}
func (v *int64V) Assign(o Value) {
*v = int64V(o.(IntValue).Get());
}
func (v *int64V) Get() int64 {
return int64(*v);
}
@ -255,14 +254,14 @@ func (v *int64V) Set(x int64) {
type intV int
func (*intV) Type() Type {
return IntType;
}
func (v *intV) String() string {
return fmt.Sprint(*v);
}
func (v *intV) Assign(o Value) {
*v = intV(o.(IntValue).Get());
}
func (v *intV) Get() int64 {
return int64(*v);
}
@ -271,23 +270,23 @@ func (v *intV) Set(x int64) {
*v = intV(x);
}
func (t *intType) value(v int64) IntValue {
func (t *intType) Zero() Value {
switch Type(t) {
case Int8Type:
res := int8V(v);
res := int8V(0);
return &res;
case Int16Type:
res := int16V(v);
res := int16V(0);
return &res;
case Int32Type:
res := int32V(v);
res := int32V(0);
return &res;
case Int64Type:
res := int64V(v);
res := int64V(0);
return &res;
case IntType:
res := intV(v);
res := intV(0);
return &res;
}
panic("unknown int type ", t.String());
@ -301,20 +300,20 @@ type idealIntV struct {
V *bignum.Integer;
}
func (*idealIntV) Type() Type {
return IdealIntType;
}
func (v *idealIntV) String() string {
return v.V.String();
}
func (v *idealIntV) Assign(o Value) {
v.V = o.(IdealIntValue).Get();
}
func (v *idealIntV) Get() *bignum.Integer {
return v.V;
}
func (t *idealIntType) value(v *bignum.Integer) IdealIntValue {
return &idealIntV{v};
func (t *idealIntType) Zero() Value {
return &idealIntV{bignum.Int(0)};
}
/*
@ -323,14 +322,14 @@ func (t *idealIntType) value(v *bignum.Integer) IdealIntValue {
type float32V float32
func (*float32V) Type() Type {
return Float32Type;
}
func (v *float32V) String() string {
return fmt.Sprint(*v);
}
func (v *float32V) Assign(o Value) {
*v = float32V(o.(FloatValue).Get());
}
func (v *float32V) Get() float64 {
return float64(*v);
}
@ -341,14 +340,14 @@ func (v *float32V) Set(x float64) {
type float64V float64
func (*float64V) Type() Type {
return Float64Type;
}
func (v *float64V) String() string {
return fmt.Sprint(*v);
}
func (v *float64V) Assign(o Value) {
*v = float64V(o.(FloatValue).Get());
}
func (v *float64V) Get() float64 {
return float64(*v);
}
@ -359,14 +358,14 @@ func (v *float64V) Set(x float64) {
type floatV float
func (*floatV) Type() Type {
return FloatType;
}
func (v *floatV) String() string {
return fmt.Sprint(*v);
}
func (v *floatV) Assign(o Value) {
*v = floatV(o.(FloatValue).Get());
}
func (v *floatV) Get() float64 {
return float64(*v);
}
@ -375,16 +374,16 @@ func (v *floatV) Set(x float64) {
*v = floatV(x);
}
func (t *floatType) value(v float64) FloatValue {
func (t *floatType) Zero() Value {
switch Type(t) {
case Float32Type:
res := float32V(v);
res := float32V(0);
return &res;
case Float64Type:
res := float64V(v);
res := float64V(0);
return &res;
case FloatType:
res := floatV(v);
res := floatV(0);
return &res;
}
panic("unknown float type ", t.String());
@ -398,20 +397,20 @@ type idealFloatV struct {
V *bignum.Rational;
}
func (*idealFloatV) Type() Type {
return IdealFloatType;
}
func (v *idealFloatV) String() string {
return ratToString(v.V);
}
func (v *idealFloatV) Assign(o Value) {
v.V = o.(IdealFloatValue).Get();
}
func (v *idealFloatV) Get() *bignum.Rational {
return v.V;
}
func (t *idealFloatType) value(v *bignum.Rational) IdealFloatValue {
return &idealFloatV{v};
func (t *idealFloatType) Zero() Value {
return &idealFloatV{bignum.Rat(1, 0)};
}
/*
@ -420,14 +419,14 @@ func (t *idealFloatType) value(v *bignum.Rational) IdealFloatValue {
type stringV string
func (*stringV) Type() Type {
return StringType;
}
func (v *stringV) String() string {
return fmt.Sprint(*v);
}
func (v *stringV) Assign(o Value) {
*v = stringV(o.(StringValue).Get());
}
func (v *stringV) Get() string {
return string(*v);
}
@ -436,8 +435,8 @@ func (v *stringV) Set(x string) {
*v = stringV(x);
}
func (t *stringType) value(v string) StringValue {
res := stringV(v);
func (t *stringType) Zero() Value {
res := stringV("");
return &res;
}
@ -447,14 +446,18 @@ func (t *stringType) value(v string) StringValue {
type arrayV []Value
func (*arrayV) Type() Type {
panic("Not implemented");
}
func (v *arrayV) String() string {
return fmt.Sprint(*v);
}
func (v *arrayV) Assign(o Value) {
oa := o.(ArrayValue);
l := int64(len(*v));
for i := int64(0); i < l; i++ {
(*v)[i].Assign(oa.Elem(i));
}
}
func (v *arrayV) Get() ArrayValue {
return v;
}
@ -463,8 +466,16 @@ func (v *arrayV) Elem(i int64) Value {
return (*v)[i];
}
func (t *ArrayType) value(v []Value) ArrayValue {
res := arrayV(v);
func (t *ArrayType) Zero() Value {
res := arrayV(make([]Value, t.Len));
// TODO(austin) It's unfortunate that each element is
// separately heap allocated. We could add ZeroArray to
// everything, though that doesn't help with multidimensional
// arrays. Or we could do something unsafe. We'll have this
// same problem with structs.
for i := int64(0); i < t.Len; i++ {
res[i] = t.Elem.Zero();
}
return &res;
}
@ -477,14 +488,14 @@ type ptrV struct {
target Value;
}
func (v *ptrV) Type() Type {
return NewPtrType(v.target.Type());
}
func (v *ptrV) String() string {
return "&" + v.target.String();
}
func (v *ptrV) Assign(o Value) {
v.target = o.(PtrValue).Get();
}
func (v *ptrV) Get() Value {
return v.target;
}
@ -493,7 +504,7 @@ func (v *ptrV) Set(x Value) {
v.target = x;
}
func (t *PtrType) value(v Value) PtrValue {
res := ptrV{v};
func (t *PtrType) Zero() Value {
res := ptrV{nil};
return &res;
}