+++ /dev/null
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package interp
-
-import (
- "bytes"
- "fmt"
- "go/constant"
- "go/token"
- "go/types"
- "os"
- "reflect"
- "strings"
- "sync"
- "unsafe"
-
- "golang.org/x/tools/go/ssa"
-)
-
-// If the target program panics, the interpreter panics with this type.
-type targetPanic struct {
- v value
-}
-
-func (p targetPanic) String() string {
- return toString(p.v)
-}
-
-// If the target program calls exit, the interpreter panics with this type.
-type exitPanic int
-
-// constValue returns the value of the constant with the
-// dynamic type tag appropriate for c.Type().
-func constValue(c *ssa.Const) value {
- if c.IsNil() {
- return zero(c.Type()) // typed nil
- }
-
- if t, ok := c.Type().Underlying().(*types.Basic); ok {
- // TODO(adonovan): eliminate untyped constants from SSA form.
- switch t.Kind() {
- case types.Bool, types.UntypedBool:
- return constant.BoolVal(c.Value)
- case types.Int, types.UntypedInt:
- // Assume sizeof(int) is same on host and target.
- return int(c.Int64())
- case types.Int8:
- return int8(c.Int64())
- case types.Int16:
- return int16(c.Int64())
- case types.Int32, types.UntypedRune:
- return int32(c.Int64())
- case types.Int64:
- return c.Int64()
- case types.Uint:
- // Assume sizeof(uint) is same on host and target.
- return uint(c.Uint64())
- case types.Uint8:
- return uint8(c.Uint64())
- case types.Uint16:
- return uint16(c.Uint64())
- case types.Uint32:
- return uint32(c.Uint64())
- case types.Uint64:
- return c.Uint64()
- case types.Uintptr:
- // Assume sizeof(uintptr) is same on host and target.
- return uintptr(c.Uint64())
- case types.Float32:
- return float32(c.Float64())
- case types.Float64, types.UntypedFloat:
- return c.Float64()
- case types.Complex64:
- return complex64(c.Complex128())
- case types.Complex128, types.UntypedComplex:
- return c.Complex128()
- case types.String, types.UntypedString:
- if c.Value.Kind() == constant.String {
- return constant.StringVal(c.Value)
- }
- return string(rune(c.Int64()))
- }
- }
-
- panic(fmt.Sprintf("constValue: %s", c))
-}
-
-// 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 {
- // TODO(adonovan): make it an invariant that
- // this is unreachable. Currently some
- // constants have 'untyped' types when they
- // should be defaulted by the typechecker.
- t = types.Default(t).(*types.Basic)
- }
- switch t.Kind() {
- case types.Bool:
- return false
- case types.Int:
- return int(0)
- case types.Int8:
- return int8(0)
- case types.Int16:
- return int16(0)
- case types.Int32:
- return int32(0)
- case types.Int64:
- return int64(0)
- case types.Uint:
- return uint(0)
- case types.Uint8:
- return uint8(0)
- case types.Uint16:
- return uint16(0)
- case types.Uint32:
- return uint32(0)
- case types.Uint64:
- return uint64(0)
- case types.Uintptr:
- return uintptr(0)
- case types.Float32:
- return float32(0)
- case types.Float64:
- return float64(0)
- case types.Complex64:
- return complex64(0)
- case types.Complex128:
- return complex128(0)
- case types.String:
- return ""
- case types.UnsafePointer:
- return unsafe.Pointer(nil)
- default:
- panic(fmt.Sprint("zero for unexpected type:", t))
- }
- case *types.Pointer:
- return (*value)(nil)
- case *types.Array:
- a := make(array, t.Len())
- for i := range a {
- a[i] = zero(t.Elem())
- }
- return a
- case *types.Named:
- return zero(t.Underlying())
- case *types.Interface:
- return iface{} // nil type, methodset and value
- case *types.Slice:
- return []value(nil)
- case *types.Struct:
- s := make(structure, t.NumFields())
- for i := range s {
- s[i] = zero(t.Field(i).Type())
- }
- return s
- case *types.Tuple:
- if t.Len() == 1 {
- return zero(t.At(0).Type())
- }
- s := make(tuple, t.Len())
- for i := range s {
- s[i] = zero(t.At(i).Type())
- }
- return s
- case *types.Chan:
- return chan value(nil)
- case *types.Map:
- if usesBuiltinMap(t.Key()) {
- return map[value]value(nil)
- }
- return (*hashmap)(nil)
- case *types.Signature:
- return (*ssa.Function)(nil)
- }
- panic(fmt.Sprint("zero: unexpected ", t))
-}
-
-// slice returns x[lo:hi:max]. Any of lo, hi and max may be nil.
-func slice(x, lo, hi, max value) value {
- var Len, Cap int
- switch x := x.(type) {
- case string:
- Len = len(x)
- case []value:
- Len = len(x)
- Cap = cap(x)
- case *value: // *array
- a := (*x).(array)
- Len = len(a)
- Cap = cap(a)
- }
-
- l := 0
- if lo != nil {
- l = asInt(lo)
- }
-
- h := Len
- if hi != nil {
- h = asInt(hi)
- }
-
- m := Cap
- if max != nil {
- m = asInt(max)
- }
-
- switch x := x.(type) {
- case string:
- return x[l:h]
- case []value:
- return x[l:h:m]
- case *value: // *array
- a := (*x).(array)
- return []value(a)[l:h:m]
- }
- 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 = zero(instr.X.Type().Underlying().(*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, t types.Type, 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 eqnil(t, x, y)
-
- case token.NEQ:
- return !eqnil(t, 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))
-}
-
-// eqnil returns the comparison x == y using the equivalence relation
-// appropriate for type t.
-// If t is a reference type, at most one of x or y may be a nil value
-// of that type.
-//
-func eqnil(t types.Type, x, y value) bool {
- switch t.Underlying().(type) {
- case *types.Map, *types.Signature, *types.Slice:
- // Since these types don't support comparison,
- // one of the operands must be a literal nil.
- switch x := x.(type) {
- case *hashmap:
- return (x != nil) == (y.(*hashmap) != nil)
- case map[value]value:
- return (x != nil) == (y.(map[value]value) != nil)
- case *ssa.Function:
- switch y := y.(type) {
- case *ssa.Function:
- return (x != nil) == (y != nil)
- case *closure:
- return true
- }
- case *closure:
- return (x != nil) == (y.(*ssa.Function) != nil)
- case []value:
- return (x != nil) == (y.([]value) != nil)
- }
- panic(fmt.Sprintf("eqnil(%s): illegal dynamic type: %T", t, x))
- }
-
- return equals(t, x, 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(instr.X.Type().Underlying().(*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 complex64:
- return -x
- case complex128:
- return -x
- }
- case token.MUL:
- return load(deref(instr.X.Type()), x.(*value))
- 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 itf.t == nil {
- err = fmt.Sprintf("interface conversion: interface is nil, not %s", instr.AssertedType)
-
- } else if idst, ok := instr.AssertedType.Underlying().(*types.Interface); ok {
- v = itf
- err = checkInterface(i, idst, itf)
-
- } else if types.Identical(itf.t, instr.AssertedType) {
- v = itf.v // extract value
-
- } else {
- err = fmt.Sprintf("interface conversion: interface is %s, not %s", itf.t, instr.AssertedType)
- }
-
- if err != "" {
- if !instr.CommaOk {
- panic(err)
- }
- return tuple{zero(instr.AssertedType), false}
- }
- if instr.CommaOk {
- return tuple{v, true}
- }
- return v
-}
-
-// If CapturedOutput is non-nil, all writes by the interpreted program
-// to file descriptors 1 and 2 will also be written to CapturedOutput.
-//
-// (The $GOROOT/test system requires that the test be considered a
-// failure if "BUG" appears in the combined stdout/stderr output, even
-// if it exits zero. This is a global variable shared by all
-// interpreters in the same process.)
-//
-var CapturedOutput *bytes.Buffer
-var capturedOutputMu sync.Mutex
-
-// write writes bytes b to the target program's standard output.
-// The print/println built-ins and the write() system call funnel
-// through here so they can be captured by the test driver.
-func print(b []byte) (int, error) {
- if CapturedOutput != nil {
- capturedOutputMu.Lock()
- CapturedOutput.Write(b) // ignore errors
- capturedOutputMu.Unlock()
- }
- return os.Stdout.Write(b)
-}
-
-// 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 or copy([]byte, string) int
- src := args[1]
- if _, ok := src.(string); ok {
- params := fn.Type().(*types.Signature).Params()
- src = conv(params.At(0).Type(), params.At(1).Type(), src)
- }
- return copy(args[0].([]value), src.([]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(any, ...)
- ln := fn.Name() == "println"
- var buf bytes.Buffer
- for i, arg := range args {
- if i > 0 && ln {
- buf.WriteRune(' ')
- }
- buf.WriteString(toString(arg))
- }
- if ln {
- buf.WriteRune('\n')
- }
- print(buf.Bytes())
- 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":
- return doRecover(caller)
-
- case "ssa:wrapnilchk":
- recv := args[0]
- if recv.(*value) == nil {
- recvType := args[1]
- methodName := args[2]
- panic(fmt.Sprintf("value method (%s).%s called using nil *%s pointer",
- recvType, methodName, recvType))
- }
- return recv
- }
-
- panic("unknown built-in: " + fn.Name())
-}
-
-func rangeIter(x value, t types.Type) iter {
- switch x := x.(type) {
- case map[value]value:
- return &mapIter{iter: reflect.ValueOf(x).MapRange()}
- case *hashmap:
- return &hashmapIter{iter: reflect.ValueOf(x.entries()).MapRange()}
- 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 := t_src.Underlying()
- ut_dst := t_dst.Underlying()
-
- // 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 fmt.Sprintf("%c", 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.
- //
- // return (*value)(x.(unsafe.Pointer))
- // 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.
- //
- // To at least preserve type-safety, we'll
- // just return the zero value of the
- // destination type.
- return zero(t_dst)
- }
-
- // 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 {
- if meth, _ := types.MissingMethod(x.t, itype, true); meth != nil {
- return fmt.Sprintf("interface conversion: %v is not %v: missing method %s",
- x.t, itype, meth.Name())
- }
- return "" // ok
-}
projects / dotfiles / .git / blobdiff