| package interp |
| |
| import ( |
| "fmt" |
| "go/token" |
| "runtime" |
| "strings" |
| "unsafe" |
| |
| "code.google.com/p/go.exp/go/exact" |
| "code.google.com/p/go.exp/go/types" |
| "code.google.com/p/go.exp/ssa" |
| ) |
| |
| // If the target program panics, the interpreter panics with this type. |
| type targetPanic struct { |
| v value |
| } |
| |
| // If the target program calls exit, the interpreter panics with this type. |
| type exitPanic int |
| |
| // literalValue returns the value of the literal with the |
| // dynamic type tag appropriate for l.Type(). |
| func literalValue(l *ssa.Literal) value { |
| if l.IsNil() { |
| return zero(l.Type()) // typed nil |
| } |
| |
| // By destination type: |
| switch t := underlyingType(l.Type()).(type) { |
| case *types.Basic: |
| switch t.Kind() { |
| case types.Bool, types.UntypedBool: |
| return exact.BoolVal(l.Value) |
| case types.Int, types.UntypedInt: |
| // Assume sizeof(int) is same on host and target. |
| return int(l.Int64()) |
| case types.Int8: |
| return int8(l.Int64()) |
| case types.Int16: |
| return int16(l.Int64()) |
| case types.Int32, types.UntypedRune: |
| return int32(l.Int64()) |
| case types.Int64: |
| return l.Int64() |
| case types.Uint: |
| // Assume sizeof(uint) is same on host and target. |
| return uint(l.Uint64()) |
| case types.Uint8: |
| return uint8(l.Uint64()) |
| case types.Uint16: |
| return uint16(l.Uint64()) |
| case types.Uint32: |
| return uint32(l.Uint64()) |
| case types.Uint64: |
| return l.Uint64() |
| case types.Uintptr: |
| // Assume sizeof(uintptr) is same on host and target. |
| return uintptr(l.Uint64()) |
| case types.Float32: |
| return float32(l.Float64()) |
| case types.Float64, types.UntypedFloat: |
| return l.Float64() |
| case types.Complex64: |
| return complex64(l.Complex128()) |
| case types.Complex128, types.UntypedComplex: |
| return l.Complex128() |
| case types.String, types.UntypedString: |
| if l.Value.Kind() == exact.String { |
| return exact.StringVal(l.Value) |
| } |
| return string(rune(l.Int64())) |
| case types.UnsafePointer: |
| panic("unsafe.Pointer literal") // not possible |
| case types.UntypedNil: |
| // nil was handled above. |
| } |
| |
| case *types.Slice: |
| switch et := underlyingType(t.Elem()).(type) { |
| case *types.Basic: |
| switch et.Kind() { |
| case types.Byte: // string -> []byte |
| var v []value |
| for _, b := range []byte(exact.StringVal(l.Value)) { |
| v = append(v, b) |
| } |
| return v |
| case types.Rune: // string -> []rune |
| var v []value |
| for _, r := range []rune(exact.StringVal(l.Value)) { |
| v = append(v, r) |
| } |
| return v |
| } |
| } |
| } |
| |
| panic(fmt.Sprintf("literalValue: Value.(type)=%T Type()=%s", l.Value, l.Type())) |
| } |
| |
| // asInt converts x, which must be an integer, to an int suitable for |
| // use as a slice or array index or operand to make(). |
| func asInt(x value) int { |
| switch x := x.(type) { |
| case int: |
| return x |
| case int8: |
| return int(x) |
| case int16: |
| return int(x) |
| case int32: |
| return int(x) |
| case int64: |
| return int(x) |
| case uint: |
| return int(x) |
| case uint8: |
| return int(x) |
| case uint16: |
| return int(x) |
| case uint32: |
| return int(x) |
| case uint64: |
| return int(x) |
| case uintptr: |
| return int(x) |
| } |
| panic(fmt.Sprintf("cannot convert %T to int", x)) |
| } |
| |
| // asUint64 converts x, which must be an unsigned integer, to a uint64 |
| // suitable for use as a bitwise shift count. |
| func asUint64(x value) uint64 { |
| switch x := x.(type) { |
| case uint: |
| return uint64(x) |
| case uint8: |
| return uint64(x) |
| case uint16: |
| return uint64(x) |
| case uint32: |
| return uint64(x) |
| case uint64: |
| return x |
| case uintptr: |
| return uint64(x) |
| } |
| panic(fmt.Sprintf("cannot convert %T to uint64", x)) |
| } |
| |
| // 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 { |
| 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.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)) |
| } |
| |
| // slice returns x[lo:hi]. Either or both of lo and hi may be nil. |
| func slice(x, lo, hi value) value { |
| l := 0 |
| if lo != nil { |
| l = asInt(lo) |
| } |
| switch x := x.(type) { |
| case string: |
| if hi != nil { |
| return x[l:asInt(hi)] |
| } |
| return x[l:] |
| case []value: |
| if hi != nil { |
| return x[l:asInt(hi)] |
| } |
| return x[l:] |
| case *value: // *array |
| a := (*x).(array) |
| if hi != nil { |
| return []value(a)[l:asInt(hi)] |
| } |
| return []value(a)[l:] |
| } |
| panic(fmt.Sprintf("slice: unexpected X type: %T", x)) |
| } |
| |
| // lookup returns x[idx] where x is a map or string. |
| func lookup(instr *ssa.Lookup, x, idx value) value { |
| switch x := x.(type) { // map or string |
| case map[value]value, *hashmap: |
| var v value |
| var ok bool |
| switch x := x.(type) { |
| case map[value]value: |
| v, ok = x[idx] |
| case *hashmap: |
| v = x.lookup(idx.(hashable)) |
| ok = v != nil |
| } |
| if ok { |
| v = copyVal(v) |
| } else { |
| v = zero(underlyingType(instr.X.Type()).(*types.Map).Elem()) |
| } |
| if instr.CommaOk { |
| v = tuple{v, ok} |
| } |
| return v |
| case string: |
| return x[asInt(idx)] |
| } |
| panic(fmt.Sprintf("unexpected x type in Lookup: %T", x)) |
| } |
| |
| // binop implements all arithmetic and logical binary operators for |
| // numeric datatypes and strings. Both operands must have identical |
| // dynamic type. |
| // |
| func binop(op token.Token, x, y value) value { |
| switch op { |
| case token.ADD: |
| switch x.(type) { |
| case int: |
| return x.(int) + y.(int) |
| case int8: |
| return x.(int8) + y.(int8) |
| case int16: |
| return x.(int16) + y.(int16) |
| case int32: |
| return x.(int32) + y.(int32) |
| case int64: |
| return x.(int64) + y.(int64) |
| case uint: |
| return x.(uint) + y.(uint) |
| case uint8: |
| return x.(uint8) + y.(uint8) |
| case uint16: |
| return x.(uint16) + y.(uint16) |
| case uint32: |
| return x.(uint32) + y.(uint32) |
| case uint64: |
| return x.(uint64) + y.(uint64) |
| case uintptr: |
| return x.(uintptr) + y.(uintptr) |
| case float32: |
| return x.(float32) + y.(float32) |
| case float64: |
| return x.(float64) + y.(float64) |
| case complex64: |
| return x.(complex64) + y.(complex64) |
| case complex128: |
| return x.(complex128) + y.(complex128) |
| case string: |
| return x.(string) + y.(string) |
| } |
| |
| case token.SUB: |
| switch x.(type) { |
| case int: |
| return x.(int) - y.(int) |
| case int8: |
| return x.(int8) - y.(int8) |
| case int16: |
| return x.(int16) - y.(int16) |
| case int32: |
| return x.(int32) - y.(int32) |
| case int64: |
| return x.(int64) - y.(int64) |
| case uint: |
| return x.(uint) - y.(uint) |
| case uint8: |
| return x.(uint8) - y.(uint8) |
| case uint16: |
| return x.(uint16) - y.(uint16) |
| case uint32: |
| return x.(uint32) - y.(uint32) |
| case uint64: |
| return x.(uint64) - y.(uint64) |
| case uintptr: |
| return x.(uintptr) - y.(uintptr) |
| case float32: |
| return x.(float32) - y.(float32) |
| case float64: |
| return x.(float64) - y.(float64) |
| case complex64: |
| return x.(complex64) - y.(complex64) |
| case complex128: |
| return x.(complex128) - y.(complex128) |
| } |
| |
| case token.MUL: |
| switch x.(type) { |
| case int: |
| return x.(int) * y.(int) |
| case int8: |
| return x.(int8) * y.(int8) |
| case int16: |
| return x.(int16) * y.(int16) |
| case int32: |
| return x.(int32) * y.(int32) |
| case int64: |
| return x.(int64) * y.(int64) |
| case uint: |
| return x.(uint) * y.(uint) |
| case uint8: |
| return x.(uint8) * y.(uint8) |
| case uint16: |
| return x.(uint16) * y.(uint16) |
| case uint32: |
| return x.(uint32) * y.(uint32) |
| case uint64: |
| return x.(uint64) * y.(uint64) |
| case uintptr: |
| return x.(uintptr) * y.(uintptr) |
| case float32: |
| return x.(float32) * y.(float32) |
| case float64: |
| return x.(float64) * y.(float64) |
| case complex64: |
| return x.(complex64) * y.(complex64) |
| case complex128: |
| return x.(complex128) * y.(complex128) |
| } |
| |
| case token.QUO: |
| switch x.(type) { |
| case int: |
| return x.(int) / y.(int) |
| case int8: |
| return x.(int8) / y.(int8) |
| case int16: |
| return x.(int16) / y.(int16) |
| case int32: |
| return x.(int32) / y.(int32) |
| case int64: |
| return x.(int64) / y.(int64) |
| case uint: |
| return x.(uint) / y.(uint) |
| case uint8: |
| return x.(uint8) / y.(uint8) |
| case uint16: |
| return x.(uint16) / y.(uint16) |
| case uint32: |
| return x.(uint32) / y.(uint32) |
| case uint64: |
| return x.(uint64) / y.(uint64) |
| case uintptr: |
| return x.(uintptr) / y.(uintptr) |
| case float32: |
| return x.(float32) / y.(float32) |
| case float64: |
| return x.(float64) / y.(float64) |
| case complex64: |
| return x.(complex64) / y.(complex64) |
| case complex128: |
| return x.(complex128) / y.(complex128) |
| } |
| |
| case token.REM: |
| switch x.(type) { |
| case int: |
| return x.(int) % y.(int) |
| case int8: |
| return x.(int8) % y.(int8) |
| case int16: |
| return x.(int16) % y.(int16) |
| case int32: |
| return x.(int32) % y.(int32) |
| case int64: |
| return x.(int64) % y.(int64) |
| case uint: |
| return x.(uint) % y.(uint) |
| case uint8: |
| return x.(uint8) % y.(uint8) |
| case uint16: |
| return x.(uint16) % y.(uint16) |
| case uint32: |
| return x.(uint32) % y.(uint32) |
| case uint64: |
| return x.(uint64) % y.(uint64) |
| case uintptr: |
| return x.(uintptr) % y.(uintptr) |
| } |
| |
| case token.AND: |
| switch x.(type) { |
| case int: |
| return x.(int) & y.(int) |
| case int8: |
| return x.(int8) & y.(int8) |
| case int16: |
| return x.(int16) & y.(int16) |
| case int32: |
| return x.(int32) & y.(int32) |
| case int64: |
| return x.(int64) & y.(int64) |
| case uint: |
| return x.(uint) & y.(uint) |
| case uint8: |
| return x.(uint8) & y.(uint8) |
| case uint16: |
| return x.(uint16) & y.(uint16) |
| case uint32: |
| return x.(uint32) & y.(uint32) |
| case uint64: |
| return x.(uint64) & y.(uint64) |
| case uintptr: |
| return x.(uintptr) & y.(uintptr) |
| } |
| |
| case token.OR: |
| switch x.(type) { |
| case int: |
| return x.(int) | y.(int) |
| case int8: |
| return x.(int8) | y.(int8) |
| case int16: |
| return x.(int16) | y.(int16) |
| case int32: |
| return x.(int32) | y.(int32) |
| case int64: |
| return x.(int64) | y.(int64) |
| case uint: |
| return x.(uint) | y.(uint) |
| case uint8: |
| return x.(uint8) | y.(uint8) |
| case uint16: |
| return x.(uint16) | y.(uint16) |
| case uint32: |
| return x.(uint32) | y.(uint32) |
| case uint64: |
| return x.(uint64) | y.(uint64) |
| case uintptr: |
| return x.(uintptr) | y.(uintptr) |
| } |
| |
| case token.XOR: |
| switch x.(type) { |
| case int: |
| return x.(int) ^ y.(int) |
| case int8: |
| return x.(int8) ^ y.(int8) |
| case int16: |
| return x.(int16) ^ y.(int16) |
| case int32: |
| return x.(int32) ^ y.(int32) |
| case int64: |
| return x.(int64) ^ y.(int64) |
| case uint: |
| return x.(uint) ^ y.(uint) |
| case uint8: |
| return x.(uint8) ^ y.(uint8) |
| case uint16: |
| return x.(uint16) ^ y.(uint16) |
| case uint32: |
| return x.(uint32) ^ y.(uint32) |
| case uint64: |
| return x.(uint64) ^ y.(uint64) |
| case uintptr: |
| return x.(uintptr) ^ y.(uintptr) |
| } |
| |
| case token.AND_NOT: |
| switch x.(type) { |
| case int: |
| return x.(int) &^ y.(int) |
| case int8: |
| return x.(int8) &^ y.(int8) |
| case int16: |
| return x.(int16) &^ y.(int16) |
| case int32: |
| return x.(int32) &^ y.(int32) |
| case int64: |
| return x.(int64) &^ y.(int64) |
| case uint: |
| return x.(uint) &^ y.(uint) |
| case uint8: |
| return x.(uint8) &^ y.(uint8) |
| case uint16: |
| return x.(uint16) &^ y.(uint16) |
| case uint32: |
| return x.(uint32) &^ y.(uint32) |
| case uint64: |
| return x.(uint64) &^ y.(uint64) |
| case uintptr: |
| return x.(uintptr) &^ y.(uintptr) |
| } |
| |
| case token.SHL: |
| y := asUint64(y) |
| switch x.(type) { |
| case int: |
| return x.(int) << y |
| case int8: |
| return x.(int8) << y |
| case int16: |
| return x.(int16) << y |
| case int32: |
| return x.(int32) << y |
| case int64: |
| return x.(int64) << y |
| case uint: |
| return x.(uint) << y |
| case uint8: |
| return x.(uint8) << y |
| case uint16: |
| return x.(uint16) << y |
| case uint32: |
| return x.(uint32) << y |
| case uint64: |
| return x.(uint64) << y |
| case uintptr: |
| return x.(uintptr) << y |
| } |
| |
| case token.SHR: |
| y := asUint64(y) |
| switch x.(type) { |
| case int: |
| return x.(int) >> y |
| case int8: |
| return x.(int8) >> y |
| case int16: |
| return x.(int16) >> y |
| case int32: |
| return x.(int32) >> y |
| case int64: |
| return x.(int64) >> y |
| case uint: |
| return x.(uint) >> y |
| case uint8: |
| return x.(uint8) >> y |
| case uint16: |
| return x.(uint16) >> y |
| case uint32: |
| return x.(uint32) >> y |
| case uint64: |
| return x.(uint64) >> y |
| case uintptr: |
| return x.(uintptr) >> y |
| } |
| |
| case token.LSS: |
| switch x.(type) { |
| case int: |
| return x.(int) < y.(int) |
| case int8: |
| return x.(int8) < y.(int8) |
| case int16: |
| return x.(int16) < y.(int16) |
| case int32: |
| return x.(int32) < y.(int32) |
| case int64: |
| return x.(int64) < y.(int64) |
| case uint: |
| return x.(uint) < y.(uint) |
| case uint8: |
| return x.(uint8) < y.(uint8) |
| case uint16: |
| return x.(uint16) < y.(uint16) |
| case uint32: |
| return x.(uint32) < y.(uint32) |
| case uint64: |
| return x.(uint64) < y.(uint64) |
| case uintptr: |
| return x.(uintptr) < y.(uintptr) |
| case float32: |
| return x.(float32) < y.(float32) |
| case float64: |
| return x.(float64) < y.(float64) |
| case string: |
| return x.(string) < y.(string) |
| } |
| |
| case token.LEQ: |
| switch x.(type) { |
| case int: |
| return x.(int) <= y.(int) |
| case int8: |
| return x.(int8) <= y.(int8) |
| case int16: |
| return x.(int16) <= y.(int16) |
| case int32: |
| return x.(int32) <= y.(int32) |
| case int64: |
| return x.(int64) <= y.(int64) |
| case uint: |
| return x.(uint) <= y.(uint) |
| case uint8: |
| return x.(uint8) <= y.(uint8) |
| case uint16: |
| return x.(uint16) <= y.(uint16) |
| case uint32: |
| return x.(uint32) <= y.(uint32) |
| case uint64: |
| return x.(uint64) <= y.(uint64) |
| case uintptr: |
| return x.(uintptr) <= y.(uintptr) |
| case float32: |
| return x.(float32) <= y.(float32) |
| case float64: |
| return x.(float64) <= y.(float64) |
| case string: |
| return x.(string) <= y.(string) |
| } |
| |
| case token.EQL: |
| return equals(x, y) |
| |
| case token.NEQ: |
| return !equals(x, y) |
| |
| case token.GTR: |
| switch x.(type) { |
| case int: |
| return x.(int) > y.(int) |
| case int8: |
| return x.(int8) > y.(int8) |
| case int16: |
| return x.(int16) > y.(int16) |
| case int32: |
| return x.(int32) > y.(int32) |
| case int64: |
| return x.(int64) > y.(int64) |
| case uint: |
| return x.(uint) > y.(uint) |
| case uint8: |
| return x.(uint8) > y.(uint8) |
| case uint16: |
| return x.(uint16) > y.(uint16) |
| case uint32: |
| return x.(uint32) > y.(uint32) |
| case uint64: |
| return x.(uint64) > y.(uint64) |
| case uintptr: |
| return x.(uintptr) > y.(uintptr) |
| case float32: |
| return x.(float32) > y.(float32) |
| case float64: |
| return x.(float64) > y.(float64) |
| case string: |
| return x.(string) > y.(string) |
| } |
| |
| case token.GEQ: |
| switch x.(type) { |
| case int: |
| return x.(int) >= y.(int) |
| case int8: |
| return x.(int8) >= y.(int8) |
| case int16: |
| return x.(int16) >= y.(int16) |
| case int32: |
| return x.(int32) >= y.(int32) |
| case int64: |
| return x.(int64) >= y.(int64) |
| case uint: |
| return x.(uint) >= y.(uint) |
| case uint8: |
| return x.(uint8) >= y.(uint8) |
| case uint16: |
| return x.(uint16) >= y.(uint16) |
| case uint32: |
| return x.(uint32) >= y.(uint32) |
| case uint64: |
| return x.(uint64) >= y.(uint64) |
| case uintptr: |
| return x.(uintptr) >= y.(uintptr) |
| case float32: |
| return x.(float32) >= y.(float32) |
| case float64: |
| return x.(float64) >= y.(float64) |
| case string: |
| return x.(string) >= y.(string) |
| } |
| } |
| panic(fmt.Sprintf("invalid binary op: %T %s %T", x, op, y)) |
| } |
| |
| func unop(instr *ssa.UnOp, x value) value { |
| switch instr.Op { |
| case token.ARROW: // receive |
| v, ok := <-x.(chan value) |
| if !ok { |
| v = zero(underlyingType(instr.X.Type()).(*types.Chan).Elem()) |
| } |
| if instr.CommaOk { |
| v = tuple{v, ok} |
| } |
| return v |
| case token.SUB: |
| switch x := x.(type) { |
| case int: |
| return -x |
| case int8: |
| return -x |
| case int16: |
| return -x |
| case int32: |
| return -x |
| case int64: |
| return -x |
| case uint: |
| return -x |
| case uint8: |
| return -x |
| case uint16: |
| return -x |
| case uint32: |
| return -x |
| case uint64: |
| return -x |
| case uintptr: |
| return -x |
| case float32: |
| return -x |
| case float64: |
| return -x |
| } |
| case token.MUL: |
| return copyVal(*x.(*value)) // load |
| case token.NOT: |
| return !x.(bool) |
| case token.XOR: |
| switch x := x.(type) { |
| case int: |
| return ^x |
| case int8: |
| return ^x |
| case int16: |
| return ^x |
| case int32: |
| return ^x |
| case int64: |
| return ^x |
| case uint: |
| return ^x |
| case uint8: |
| return ^x |
| case uint16: |
| return ^x |
| case uint32: |
| return ^x |
| case uint64: |
| return ^x |
| case uintptr: |
| return ^x |
| } |
| } |
| panic(fmt.Sprintf("invalid unary op %s %T", instr.Op, x)) |
| } |
| |
| // typeAssert checks whether dynamic type of itf is instr.AssertedType. |
| // It returns the extracted value on success, and panics on failure, |
| // unless instr.CommaOk, in which case it always returns a "value,ok" tuple. |
| // |
| func typeAssert(i *interpreter, instr *ssa.TypeAssert, itf iface) value { |
| var v value |
| err := "" |
| if idst, ok := underlyingType(instr.AssertedType).(*types.Interface); ok { |
| v = itf |
| err = checkInterface(i, idst, itf) |
| |
| } else if types.IsIdentical(itf.t, instr.AssertedType) { |
| v = copyVal(itf.v) // extract value |
| |
| } else { |
| err = fmt.Sprintf("type assert failed: expected %s, got %s", instr.AssertedType, itf.t) |
| } |
| |
| if err != "" { |
| if !instr.CommaOk { |
| panic(err) |
| } |
| return tuple{zero(instr.AssertedType), false} |
| } |
| if instr.CommaOk { |
| return tuple{v, true} |
| } |
| return v |
| } |
| |
| // callBuiltin interprets a call to builtin fn with arguments args, |
| // returning its result. |
| func callBuiltin(caller *frame, callpos token.Pos, fn *ssa.Builtin, args []value) value { |
| switch fn.Name() { |
| case "append": |
| if len(args) == 1 { |
| return args[0] |
| } |
| if s, ok := args[1].(string); ok { |
| // append([]byte, ...string) []byte |
| arg0 := args[0].([]value) |
| for i := 0; i < len(s); i++ { |
| arg0 = append(arg0, s[i]) |
| } |
| return arg0 |
| } |
| // append([]T, ...[]T) []T |
| return append(args[0].([]value), args[1].([]value)...) |
| |
| case "copy": // copy([]T, []T) int |
| if _, ok := args[1].(string); ok { |
| panic("copy([]byte, string) not yet implemented") |
| } |
| return copy(args[0].([]value), args[1].([]value)) |
| |
| case "close": // close(chan T) |
| close(args[0].(chan value)) |
| return nil |
| |
| case "delete": // delete(map[K]value, K) |
| switch m := args[0].(type) { |
| case map[value]value: |
| delete(m, args[1]) |
| case *hashmap: |
| m.delete(args[1].(hashable)) |
| default: |
| panic(fmt.Sprintf("illegal map type: %T", m)) |
| } |
| return nil |
| |
| case "print", "println": // print(anytype, ...interface{}) |
| ln := fn.Name() == "println" |
| fmt.Print(toString(args[0])) |
| if len(args) == 2 { |
| for _, arg := range args[1].([]value) { |
| if ln { |
| fmt.Print(" ") |
| } |
| fmt.Print(toString(arg)) |
| } |
| } |
| if ln { |
| fmt.Println() |
| } |
| return nil |
| |
| case "len": |
| switch x := args[0].(type) { |
| case string: |
| return len(x) |
| case array: |
| return len(x) |
| case *value: |
| return len((*x).(array)) |
| case []value: |
| return len(x) |
| case map[value]value: |
| return len(x) |
| case *hashmap: |
| return x.len() |
| case chan value: |
| return len(x) |
| default: |
| panic(fmt.Sprintf("len: illegal operand: %T", x)) |
| } |
| |
| case "cap": |
| switch x := args[0].(type) { |
| case array: |
| return cap(x) |
| case *value: |
| return cap((*x).(array)) |
| case []value: |
| return cap(x) |
| case chan value: |
| return cap(x) |
| default: |
| panic(fmt.Sprintf("cap: illegal operand: %T", x)) |
| } |
| |
| case "real": |
| switch c := args[0].(type) { |
| case complex64: |
| return real(c) |
| case complex128: |
| return real(c) |
| default: |
| panic(fmt.Sprintf("real: illegal operand: %T", c)) |
| } |
| |
| case "imag": |
| switch c := args[0].(type) { |
| case complex64: |
| return imag(c) |
| case complex128: |
| return imag(c) |
| default: |
| panic(fmt.Sprintf("imag: illegal operand: %T", c)) |
| } |
| |
| case "complex": |
| switch f := args[0].(type) { |
| case float32: |
| return complex(f, args[1].(float32)) |
| case float64: |
| return complex(f, args[1].(float64)) |
| default: |
| panic(fmt.Sprintf("complex: illegal operand: %T", f)) |
| } |
| |
| case "panic": |
| // ssa.Panic handles most cases; this is only for "go |
| // panic" or "defer panic". |
| panic(targetPanic{args[0]}) |
| |
| case "recover": |
| // recover() must be exactly one level beneath the |
| // deferred function (two levels beneath the panicking |
| // function) to have any effect. Thus we ignore both |
| // "defer recover()" and "defer f() -> g() -> |
| // recover()". |
| if caller.i.mode&DisableRecover == 0 && |
| caller != nil && caller.status == stRunning && |
| caller.caller != nil && caller.caller.status == stPanic { |
| caller.caller.status = stComplete |
| p := caller.caller.panic |
| caller.caller.panic = nil |
| switch p := p.(type) { |
| case targetPanic: |
| return p.v |
| case runtime.Error: |
| // TODO(adonovan): must box this up |
| // inside instance of interface 'error'. |
| return iface{types.Typ[types.String], p.Error()} |
| case string: |
| return iface{types.Typ[types.String], p} |
| default: |
| panic(fmt.Sprintf("unexpected panic type %T in target call to recover()", p)) |
| } |
| } |
| return iface{} |
| } |
| |
| panic("unknown built-in: " + fn.Name()) |
| } |
| |
| func rangeIter(x value, t types.Type) iter { |
| switch x := x.(type) { |
| case map[value]value: |
| // TODO(adonovan): fix: leaks goroutines and channels |
| // on each incomplete map iteration. We need to open |
| // up an iteration interface using the |
| // reflect.(Value).MapKeys machinery. |
| it := make(mapIter) |
| x2 := x // TODO(gri): workaround for go/types bug in typeswitch+funclit. |
| go func() { |
| for k, v := range x2 { |
| it <- [2]value{k, v} |
| } |
| close(it) |
| }() |
| return it |
| case *hashmap: |
| // TODO(adonovan): fix: leaks goroutines and channels |
| // on each incomplete map iteration. We need to open |
| // up an iteration interface using the |
| // reflect.(Value).MapKeys machinery. |
| it := make(mapIter) |
| x2 := x // TODO(gri): workaround for go/types bug in typeswitch+funclit. |
| go func() { |
| for _, e := range x2.table { |
| for e != nil { |
| it <- [2]value{e.key, e.value} |
| e = e.next |
| } |
| } |
| close(it) |
| }() |
| return it |
| case string: |
| return &stringIter{Reader: strings.NewReader(x)} |
| } |
| panic(fmt.Sprintf("cannot range over %T", x)) |
| } |
| |
| // widen widens a basic typed value x to the widest type of its |
| // category, one of: |
| // bool, int64, uint64, float64, complex128, string. |
| // This is inefficient but reduces the size of the cross-product of |
| // cases we have to consider. |
| // |
| func widen(x value) value { |
| switch y := x.(type) { |
| case bool, int64, uint64, float64, complex128, string, unsafe.Pointer: |
| return x |
| case int: |
| return int64(y) |
| case int8: |
| return int64(y) |
| case int16: |
| return int64(y) |
| case int32: |
| return int64(y) |
| case uint: |
| return uint64(y) |
| case uint8: |
| return uint64(y) |
| case uint16: |
| return uint64(y) |
| case uint32: |
| return uint64(y) |
| case uintptr: |
| return uint64(y) |
| case float32: |
| return float64(y) |
| case complex64: |
| return complex128(y) |
| } |
| panic(fmt.Sprintf("cannot widen %T", x)) |
| } |
| |
| // conv converts the value x of type t_src to type t_dst and returns |
| // the result. |
| // Possible cases are described with the ssa.Convert operator. |
| // |
| func conv(t_dst, t_src types.Type, x value) value { |
| ut_src := underlyingType(t_src) |
| ut_dst := underlyingType(t_dst) |
| |
| // Destination type is not an "untyped" type. |
| if b, ok := ut_dst.(*types.Basic); ok && b.Info()&types.IsUntyped != 0 { |
| panic("oops: conversion to 'untyped' type: " + b.String()) |
| } |
| |
| // Nor is it an interface type. |
| if _, ok := ut_dst.(*types.Interface); ok { |
| if _, ok := ut_src.(*types.Interface); ok { |
| panic("oops: Convert should be ChangeInterface") |
| } else { |
| panic("oops: Convert should be MakeInterface") |
| } |
| } |
| |
| // Remaining conversions: |
| // + untyped string/number/bool constant to a specific |
| // representation. |
| // + conversions between non-complex numeric types. |
| // + conversions between complex numeric types. |
| // + integer/[]byte/[]rune -> string. |
| // + string -> []byte/[]rune. |
| // |
| // All are treated the same: first we extract the value to the |
| // widest representation (int64, uint64, float64, complex128, |
| // or string), then we convert it to the desired type. |
| |
| switch ut_src := ut_src.(type) { |
| case *types.Pointer: |
| switch ut_dst := ut_dst.(type) { |
| case *types.Basic: |
| // *value to unsafe.Pointer? |
| if ut_dst.Kind() == types.UnsafePointer { |
| return unsafe.Pointer(x.(*value)) |
| } |
| } |
| |
| case *types.Slice: |
| // []byte or []rune -> string |
| // TODO(adonovan): fix: type B byte; conv([]B -> string). |
| switch ut_src.Elem().(*types.Basic).Kind() { |
| case types.Byte: |
| x := x.([]value) |
| b := make([]byte, 0, len(x)) |
| for i := range x { |
| b = append(b, x[i].(byte)) |
| } |
| return string(b) |
| |
| case types.Rune: |
| x := x.([]value) |
| r := make([]rune, 0, len(x)) |
| for i := range x { |
| r = append(r, x[i].(rune)) |
| } |
| return string(r) |
| } |
| |
| case *types.Basic: |
| x = widen(x) |
| |
| // integer -> string? |
| // TODO(adonovan): fix: test integer -> named alias of string. |
| if ut_src.Info()&types.IsInteger != 0 { |
| if ut_dst, ok := ut_dst.(*types.Basic); ok && ut_dst.Kind() == types.String { |
| return string(asInt(x)) |
| } |
| } |
| |
| // string -> []rune, []byte or string? |
| if s, ok := x.(string); ok { |
| switch ut_dst := ut_dst.(type) { |
| case *types.Slice: |
| var res []value |
| // TODO(adonovan): fix: test named alias of rune, byte. |
| switch ut_dst.Elem().(*types.Basic).Kind() { |
| case types.Rune: |
| for _, r := range []rune(s) { |
| res = append(res, r) |
| } |
| return res |
| case types.Byte: |
| for _, b := range []byte(s) { |
| res = append(res, b) |
| } |
| return res |
| } |
| case *types.Basic: |
| if ut_dst.Kind() == types.String { |
| return x.(string) |
| } |
| } |
| break // fail: no other conversions for string |
| } |
| |
| // unsafe.Pointer -> *value |
| if ut_src.Kind() == types.UnsafePointer { |
| // TODO(adonovan): this is wrong and cannot |
| // really be fixed with the current design. |
| // |
| // It creates a new pointer of a different |
| // type but the underlying interface value |
| // knows its "true" type and so cannot be |
| // meaningfully used through the new pointer. |
| // |
| // To make this work, the interpreter needs to |
| // simulate the memory layout of a real |
| // compiled implementation. |
| return (*value)(x.(unsafe.Pointer)) |
| } |
| |
| // Conversions between complex numeric types? |
| if ut_src.Info()&types.IsComplex != 0 { |
| switch ut_dst.(*types.Basic).Kind() { |
| case types.Complex64: |
| return complex64(x.(complex128)) |
| case types.Complex128: |
| return x.(complex128) |
| } |
| break // fail: no other conversions for complex |
| } |
| |
| // Conversions between non-complex numeric types? |
| if ut_src.Info()&types.IsNumeric != 0 { |
| kind := ut_dst.(*types.Basic).Kind() |
| switch x := x.(type) { |
| case int64: // signed integer -> numeric? |
| switch kind { |
| case types.Int: |
| return int(x) |
| case types.Int8: |
| return int8(x) |
| case types.Int16: |
| return int16(x) |
| case types.Int32: |
| return int32(x) |
| case types.Int64: |
| return int64(x) |
| case types.Uint: |
| return uint(x) |
| case types.Uint8: |
| return uint8(x) |
| case types.Uint16: |
| return uint16(x) |
| case types.Uint32: |
| return uint32(x) |
| case types.Uint64: |
| return uint64(x) |
| case types.Uintptr: |
| return uintptr(x) |
| case types.Float32: |
| return float32(x) |
| case types.Float64: |
| return float64(x) |
| } |
| |
| case uint64: // unsigned integer -> numeric? |
| switch kind { |
| case types.Int: |
| return int(x) |
| case types.Int8: |
| return int8(x) |
| case types.Int16: |
| return int16(x) |
| case types.Int32: |
| return int32(x) |
| case types.Int64: |
| return int64(x) |
| case types.Uint: |
| return uint(x) |
| case types.Uint8: |
| return uint8(x) |
| case types.Uint16: |
| return uint16(x) |
| case types.Uint32: |
| return uint32(x) |
| case types.Uint64: |
| return uint64(x) |
| case types.Uintptr: |
| return uintptr(x) |
| case types.Float32: |
| return float32(x) |
| case types.Float64: |
| return float64(x) |
| } |
| |
| case float64: // floating point -> numeric? |
| switch kind { |
| case types.Int: |
| return int(x) |
| case types.Int8: |
| return int8(x) |
| case types.Int16: |
| return int16(x) |
| case types.Int32: |
| return int32(x) |
| case types.Int64: |
| return int64(x) |
| case types.Uint: |
| return uint(x) |
| case types.Uint8: |
| return uint8(x) |
| case types.Uint16: |
| return uint16(x) |
| case types.Uint32: |
| return uint32(x) |
| case types.Uint64: |
| return uint64(x) |
| case types.Uintptr: |
| return uintptr(x) |
| case types.Float32: |
| return float32(x) |
| case types.Float64: |
| return float64(x) |
| } |
| } |
| } |
| } |
| |
| panic(fmt.Sprintf("unsupported conversion: %s -> %s, dynamic type %T", t_src, t_dst, x)) |
| } |
| |
| // checkInterface checks that the method set of x implements the |
| // interface itype. |
| // On success it returns "", on failure, an error message. |
| // |
| func checkInterface(i *interpreter, itype *types.Interface, x iface) string { |
| mset := findMethodSet(i, x.t) |
| it := underlyingType(itype).(*types.Interface) |
| for i, n := 0, it.NumMethods(); i < n; i++ { |
| m := it.Method(i) |
| id := ssa.MakeId(m.Name(), m.Pkg()) |
| if mset[id] == nil { |
| return fmt.Sprintf("interface conversion: %v is not %v: missing method %v", x.t, itype, id) |
| } |
| } |
| return "" // ok |
| } |
| |
| // underlyingType returns the underlying type of typ. |
| // Copied from go/types.underlying. |
| // |
| func underlyingType(typ types.Type) types.Type { |
| if typ, ok := typ.(*types.Named); ok { |
| return typ.Underlying() |
| } |
| return typ |
| } |
| |
| // indirectType(typ) assumes that typ is a pointer type, |
| // or named alias thereof, and returns its base type. |
| // Panic ensues if it is not a pointer. |
| // Copied from exp/ssa.indirectType. |
| // |
| func indirectType(ptr types.Type) types.Type { |
| return underlyingType(ptr).(*types.Pointer).Elem() |
| } |
