Exemplo n.º 1
0
func (f *Finder) builtin(obj *types.Builtin, sig *types.Signature, args []ast.Expr, T types.Type) types.Type {
	switch obj.Name() {
	case "make", "new":
		// skip the type operand
		for _, arg := range args[1:] {
			f.expr(arg)
		}

	case "append":
		s := f.expr(args[0])
		if _, ok := args[len(args)-1].(*ast.Ellipsis); ok && len(args) == 2 {
			// append(x, y...)   including append([]byte, "foo"...)
			f.expr(args[1])
		} else {
			// append(x, y, z)
			tElem := s.Underlying().(*types.Slice).Elem()
			for _, arg := range args[1:] {
				f.assign(tElem, f.expr(arg))
			}
		}

	case "delete":
		m := f.expr(args[0])
		k := f.expr(args[1])
		f.assign(m.Underlying().(*types.Map).Key(), k)

	default:
		// ordinary call
		f.call(sig, args)
	}

	return T
}
Exemplo n.º 2
0
func (c *funcContext) translateStmt(stmt ast.Stmt, label string) {
	c.WritePos(stmt.Pos())

	switch s := stmt.(type) {
	case *ast.BlockStmt:
		c.printLabel(label)
		c.translateStmtList(s.List)

	case *ast.IfStmt:
		c.printLabel(label)
		if s.Init != nil {
			c.translateStmt(s.Init, "")
		}
		var caseClauses []ast.Stmt
		ifStmt := s
		for {
			caseClauses = append(caseClauses, &ast.CaseClause{List: []ast.Expr{ifStmt.Cond}, Body: ifStmt.Body.List})
			switch elseStmt := ifStmt.Else.(type) {
			case *ast.IfStmt:
				if elseStmt.Init != nil {
					caseClauses = append(caseClauses, &ast.CaseClause{List: nil, Body: []ast.Stmt{elseStmt}})
					break
				}
				ifStmt = elseStmt
				continue
			case *ast.BlockStmt:
				caseClauses = append(caseClauses, &ast.CaseClause{List: nil, Body: elseStmt.List})
			case *ast.EmptyStmt, nil:
				// no else clause
			default:
				panic(fmt.Sprintf("Unhandled else: %T\n", elseStmt))
			}
			break
		}
		c.translateBranchingStmt(caseClauses, false, c.translateExpr, nil, "", c.flattened[s])

	case *ast.SwitchStmt:
		if s.Init != nil {
			c.translateStmt(s.Init, "")
		}
		translateCond := func(cond ast.Expr) *expression {
			return c.translateExpr(cond)
		}
		if s.Tag != nil {
			refVar := c.newVariable("_ref")
			c.Printf("%s = %s;", refVar, c.translateExpr(s.Tag))
			translateCond = func(cond ast.Expr) *expression {
				return c.translateExpr(&ast.BinaryExpr{
					X:  c.newIdent(refVar, c.p.info.Types[s.Tag].Type),
					Op: token.EQL,
					Y:  cond,
				})
			}
		}
		c.translateBranchingStmt(s.Body.List, true, translateCond, nil, label, c.flattened[s])

	case *ast.TypeSwitchStmt:
		if s.Init != nil {
			c.translateStmt(s.Init, "")
		}
		var expr ast.Expr
		var typeSwitchVar string
		switch a := s.Assign.(type) {
		case *ast.AssignStmt:
			expr = a.Rhs[0].(*ast.TypeAssertExpr).X
			typeSwitchVar = c.newVariable(a.Lhs[0].(*ast.Ident).Name)
			for _, caseClause := range s.Body.List {
				c.p.objectVars[c.p.info.Implicits[caseClause]] = typeSwitchVar
			}
		case *ast.ExprStmt:
			expr = a.X.(*ast.TypeAssertExpr).X
		}
		refVar := c.newVariable("_ref")
		c.Printf("%s = %s;", refVar, c.translateExpr(expr))
		translateCond := func(cond ast.Expr) *expression {
			if types.Identical(c.p.info.Types[cond].Type, types.Typ[types.UntypedNil]) {
				return c.formatExpr("%s === $ifaceNil", refVar)
			}
			return c.formatExpr("$assertType(%s, %s, true)[1]", refVar, c.typeName(c.p.info.Types[cond].Type))
		}
		printCaseBodyPrefix := func(index int) {
			if typeSwitchVar == "" {
				return
			}
			value := refVar
			if conds := s.Body.List[index].(*ast.CaseClause).List; len(conds) == 1 {
				t := c.p.info.Types[conds[0]].Type
				if _, isInterface := t.Underlying().(*types.Interface); !isInterface && !types.Identical(t, types.Typ[types.UntypedNil]) {
					value += ".$val"
				}
			}
			c.Printf("%s = %s;", typeSwitchVar, value)
		}
		c.translateBranchingStmt(s.Body.List, true, translateCond, printCaseBodyPrefix, label, c.flattened[s])

	case *ast.ForStmt:
		if s.Init != nil {
			c.translateStmt(s.Init, "")
		}
		cond := "true"
		if s.Cond != nil {
			cond = c.translateExpr(s.Cond).String()
		}
		c.translateLoopingStmt(cond, s.Body, nil, func() {
			if s.Post != nil {
				c.translateStmt(s.Post, "")
			}
		}, label, c.flattened[s])

	case *ast.RangeStmt:
		refVar := c.newVariable("_ref")
		c.Printf("%s = %s;", refVar, c.translateExpr(s.X))

		switch t := c.p.info.Types[s.X].Type.Underlying().(type) {
		case *types.Basic:
			iVar := c.newVariable("_i")
			c.Printf("%s = 0;", iVar)
			runeVar := c.newVariable("_rune")
			c.translateLoopingStmt(iVar+" < "+refVar+".length", s.Body, func() {
				c.Printf("%s = $decodeRune(%s, %s);", runeVar, refVar, iVar)
				if !isBlank(s.Key) {
					c.Printf("%s", c.translateAssign(s.Key, iVar, types.Typ[types.Int], s.Tok == token.DEFINE))
				}
				if !isBlank(s.Value) {
					c.Printf("%s", c.translateAssign(s.Value, runeVar+"[0]", types.Typ[types.Rune], s.Tok == token.DEFINE))
				}
			}, func() {
				c.Printf("%s += %s[1];", iVar, runeVar)
			}, label, c.flattened[s])

		case *types.Map:
			iVar := c.newVariable("_i")
			c.Printf("%s = 0;", iVar)
			keysVar := c.newVariable("_keys")
			c.Printf("%s = $keys(%s);", keysVar, refVar)
			c.translateLoopingStmt(iVar+" < "+keysVar+".length", s.Body, func() {
				entryVar := c.newVariable("_entry")
				c.Printf("%s = %s[%s[%s]];", entryVar, refVar, keysVar, iVar)
				if !isBlank(s.Key) {
					c.Printf("%s", c.translateAssign(s.Key, entryVar+".k", t.Key(), s.Tok == token.DEFINE))
				}
				if !isBlank(s.Value) {
					c.Printf("%s", c.translateAssign(s.Value, entryVar+".v", t.Elem(), s.Tok == token.DEFINE))
				}
			}, func() {
				c.Printf("%s++;", iVar)
			}, label, c.flattened[s])

		case *types.Array, *types.Pointer, *types.Slice:
			var length string
			var elemType types.Type
			switch t2 := t.(type) {
			case *types.Array:
				length = fmt.Sprintf("%d", t2.Len())
				elemType = t2.Elem()
			case *types.Pointer:
				length = fmt.Sprintf("%d", t2.Elem().Underlying().(*types.Array).Len())
				elemType = t2.Elem().Underlying().(*types.Array).Elem()
			case *types.Slice:
				length = refVar + ".$length"
				elemType = t2.Elem()
			}
			iVar := c.newVariable("_i")
			c.Printf("%s = 0;", iVar)
			c.translateLoopingStmt(iVar+" < "+length, s.Body, func() {
				if !isBlank(s.Key) {
					c.Printf("%s", c.translateAssign(s.Key, iVar, types.Typ[types.Int], s.Tok == token.DEFINE))
				}
				if !isBlank(s.Value) {
					c.Printf("%s", c.translateAssign(s.Value, c.translateImplicitConversion(c.setType(&ast.IndexExpr{
						X:     c.newIdent(refVar, t),
						Index: c.newIdent(iVar, types.Typ[types.Int]),
					}, elemType), elemType).String(), elemType, s.Tok == token.DEFINE))
				}
			}, func() {
				c.Printf("%s++;", iVar)
			}, label, c.flattened[s])

		case *types.Chan:
			okVar := c.newIdent(c.newVariable("_ok"), types.Typ[types.Bool])
			forStmt := &ast.ForStmt{
				Body: &ast.BlockStmt{
					List: []ast.Stmt{
						&ast.AssignStmt{
							Lhs: []ast.Expr{
								s.Key,
								okVar,
							},
							Rhs: []ast.Expr{
								c.setType(&ast.UnaryExpr{X: c.newIdent(refVar, t), Op: token.ARROW}, types.NewTuple(types.NewVar(0, nil, "", t.Elem()), types.NewVar(0, nil, "", types.Typ[types.Bool]))),
							},
							Tok: s.Tok,
						},
						&ast.IfStmt{
							Cond: &ast.UnaryExpr{X: okVar, Op: token.NOT},
							Body: &ast.BlockStmt{List: []ast.Stmt{&ast.BranchStmt{Tok: token.BREAK}}},
						},
						s.Body,
					},
				},
			}
			c.flattened[forStmt] = true
			c.translateStmt(forStmt, label)

		default:
			panic("")
		}

	case *ast.BranchStmt:
		c.printLabel(label)
		labelSuffix := ""
		data := c.flowDatas[""]
		if s.Label != nil {
			labelSuffix = " " + s.Label.Name
			data = c.flowDatas[s.Label.Name]
		}
		switch s.Tok {
		case token.BREAK:
			c.PrintCond(data.endCase == 0, fmt.Sprintf("break%s;", labelSuffix), fmt.Sprintf("$s = %d; continue;", data.endCase))
		case token.CONTINUE:
			data.postStmt()
			c.PrintCond(data.beginCase == 0, fmt.Sprintf("continue%s;", labelSuffix), fmt.Sprintf("$s = %d; continue;", data.beginCase))
		case token.GOTO:
			c.PrintCond(false, "goto "+s.Label.Name, fmt.Sprintf("$s = %d; continue;", c.labelCases[s.Label.Name]))
		case token.FALLTHROUGH:
			// handled in CaseClause
		default:
			panic("Unhandled branch statment: " + s.Tok.String())
		}

	case *ast.ReturnStmt:
		c.printLabel(label)
		results := s.Results
		if c.resultNames != nil {
			if len(s.Results) != 0 {
				c.translateStmt(&ast.AssignStmt{
					Lhs: c.resultNames,
					Tok: token.ASSIGN,
					Rhs: s.Results,
				}, "")
			}
			results = c.resultNames
		}
		switch len(results) {
		case 0:
			c.Printf("return;")
		case 1:
			if c.sig.Results().Len() > 1 {
				c.Printf("return %s;", c.translateExpr(results[0]))
				return
			}
			v := c.translateImplicitConversion(results[0], c.sig.Results().At(0).Type())
			c.delayedOutput = nil
			c.Printf("return %s;", v)
		default:
			values := make([]string, len(results))
			for i, result := range results {
				values[i] = c.translateImplicitConversion(result, c.sig.Results().At(i).Type()).String()
			}
			c.delayedOutput = nil
			c.Printf("return [%s];", strings.Join(values, ", "))
		}

	case *ast.DeferStmt:
		c.printLabel(label)
		isBuiltin := false
		isJs := false
		switch fun := s.Call.Fun.(type) {
		case *ast.Ident:
			var builtin *types.Builtin
			builtin, isBuiltin = c.p.info.Uses[fun].(*types.Builtin)
			if isBuiltin && builtin.Name() == "recover" {
				c.Printf("$deferred.push([$recover, []]);")
				return
			}
		case *ast.SelectorExpr:
			isJs = isJsPackage(c.p.info.Uses[fun.Sel].Pkg())
		}
		if isBuiltin || isJs {
			args := make([]ast.Expr, len(s.Call.Args))
			for i, arg := range s.Call.Args {
				args[i] = c.newIdent(c.newVariable("_arg"), c.p.info.Types[arg].Type)
			}
			call := c.translateExpr(&ast.CallExpr{
				Fun:      s.Call.Fun,
				Args:     args,
				Ellipsis: s.Call.Ellipsis,
			})
			c.Printf("$deferred.push([function(%s) { %s; }, [%s]]);", strings.Join(c.translateExprSlice(args, nil), ", "), call, strings.Join(c.translateExprSlice(s.Call.Args, nil), ", "))
			return
		}
		sig := c.p.info.Types[s.Call.Fun].Type.Underlying().(*types.Signature)
		args := c.translateArgs(sig, s.Call.Args, s.Call.Ellipsis.IsValid())
		if len(c.blocking) != 0 {
			args = append(args, "true")
		}
		c.Printf("$deferred.push([%s, [%s]]);", c.translateExpr(s.Call.Fun), strings.Join(args, ", "))

	case *ast.AssignStmt:
		c.printLabel(label)
		if s.Tok != token.ASSIGN && s.Tok != token.DEFINE {
			var op token.Token
			switch s.Tok {
			case token.ADD_ASSIGN:
				op = token.ADD
			case token.SUB_ASSIGN:
				op = token.SUB
			case token.MUL_ASSIGN:
				op = token.MUL
			case token.QUO_ASSIGN:
				op = token.QUO
			case token.REM_ASSIGN:
				op = token.REM
			case token.AND_ASSIGN:
				op = token.AND
			case token.OR_ASSIGN:
				op = token.OR
			case token.XOR_ASSIGN:
				op = token.XOR
			case token.SHL_ASSIGN:
				op = token.SHL
			case token.SHR_ASSIGN:
				op = token.SHR
			case token.AND_NOT_ASSIGN:
				op = token.AND_NOT
			default:
				panic(s.Tok)
			}

			var parts []string
			lhs := s.Lhs[0]
			switch l := lhs.(type) {
			case *ast.IndexExpr:
				lhsVar := c.newVariable("_lhs")
				indexVar := c.newVariable("_index")
				parts = append(parts, lhsVar+" = "+c.translateExpr(l.X).String()+";")
				parts = append(parts, indexVar+" = "+c.translateExpr(l.Index).String()+";")
				lhs = c.setType(&ast.IndexExpr{
					X:     c.newIdent(lhsVar, c.p.info.Types[l.X].Type),
					Index: c.newIdent(indexVar, c.p.info.Types[l.Index].Type),
				}, c.p.info.Types[l].Type)
			case *ast.StarExpr:
				lhsVar := c.newVariable("_lhs")
				parts = append(parts, lhsVar+" = "+c.translateExpr(l.X).String()+";")
				lhs = c.setType(&ast.StarExpr{
					X: c.newIdent(lhsVar, c.p.info.Types[l.X].Type),
				}, c.p.info.Types[l].Type)
			case *ast.SelectorExpr:
				v := hasCallVisitor{c.p.info, false}
				ast.Walk(&v, l.X)
				if v.hasCall {
					lhsVar := c.newVariable("_lhs")
					parts = append(parts, lhsVar+" = "+c.translateExpr(l.X).String()+";")
					lhs = c.setType(&ast.SelectorExpr{
						X:   c.newIdent(lhsVar, c.p.info.Types[l.X].Type),
						Sel: l.Sel,
					}, c.p.info.Types[l].Type)
					c.p.info.Selections[lhs.(*ast.SelectorExpr)] = c.p.info.Selections[l]
				}
			}

			lhsType := c.p.info.Types[s.Lhs[0]].Type
			parts = append(parts, c.translateAssign(lhs, c.translateExpr(c.setType(&ast.BinaryExpr{
				X:  lhs,
				Op: op,
				Y:  c.setType(&ast.ParenExpr{X: s.Rhs[0]}, c.p.info.Types[s.Rhs[0]].Type),
			}, lhsType)).String(), lhsType, s.Tok == token.DEFINE))
			c.Printf("%s", strings.Join(parts, " "))
			return
		}

		if s.Tok == token.DEFINE {
			for _, lhs := range s.Lhs {
				if !isBlank(lhs) {
					obj := c.p.info.Defs[lhs.(*ast.Ident)]
					if obj == nil {
						obj = c.p.info.Uses[lhs.(*ast.Ident)]
					}
					c.setType(lhs, obj.Type())
				}
			}
		}

		switch {
		case len(s.Lhs) == 1 && len(s.Rhs) == 1:
			lhs := removeParens(s.Lhs[0])
			if isBlank(lhs) {
				v := hasCallVisitor{c.p.info, false}
				ast.Walk(&v, s.Rhs[0])
				if v.hasCall {
					c.Printf("%s;", c.translateExpr(s.Rhs[0]).String())
				}
				return
			}
			lhsType := c.p.info.Types[s.Lhs[0]].Type
			c.Printf("%s", c.translateAssignOfExpr(lhs, s.Rhs[0], lhsType, s.Tok == token.DEFINE))

		case len(s.Lhs) > 1 && len(s.Rhs) == 1:
			tupleVar := c.newVariable("_tuple")
			out := tupleVar + " = " + c.translateExpr(s.Rhs[0]).String() + ";"
			tuple := c.p.info.Types[s.Rhs[0]].Type.(*types.Tuple)
			for i, lhs := range s.Lhs {
				lhs = removeParens(lhs)
				if !isBlank(lhs) {
					lhsType := c.p.info.Types[s.Lhs[i]].Type
					out += " " + c.translateAssignOfExpr(lhs, c.newIdent(fmt.Sprintf("%s[%d]", tupleVar, i), tuple.At(i).Type()), lhsType, s.Tok == token.DEFINE)
				}
			}
			c.Printf("%s", out)
		case len(s.Lhs) == len(s.Rhs):
			tmpVars := make([]string, len(s.Rhs))
			var parts []string
			for i, rhs := range s.Rhs {
				tmpVars[i] = c.newVariable("_tmp")
				if isBlank(removeParens(s.Lhs[i])) {
					v := hasCallVisitor{c.p.info, false}
					ast.Walk(&v, rhs)
					if v.hasCall {
						c.Printf("%s;", c.translateExpr(rhs).String())
					}
					continue
				}
				lhsType := c.p.info.Types[s.Lhs[i]].Type
				parts = append(parts, c.translateAssignOfExpr(c.newIdent(tmpVars[i], c.p.info.Types[s.Lhs[i]].Type), rhs, lhsType, true))
			}
			for i, lhs := range s.Lhs {
				lhs = removeParens(lhs)
				if !isBlank(lhs) {
					parts = append(parts, c.translateAssign(lhs, tmpVars[i], c.p.info.Types[lhs].Type, s.Tok == token.DEFINE))
				}
			}
			c.Printf("%s", strings.Join(parts, " "))

		default:
			panic("Invalid arity of AssignStmt.")

		}

	case *ast.IncDecStmt:
		t := c.p.info.Types[s.X].Type
		if iExpr, isIExpr := s.X.(*ast.IndexExpr); isIExpr {
			switch u := c.p.info.Types[iExpr.X].Type.Underlying().(type) {
			case *types.Array:
				t = u.Elem()
			case *types.Slice:
				t = u.Elem()
			case *types.Map:
				t = u.Elem()
			}
		}

		tok := token.ADD_ASSIGN
		if s.Tok == token.DEC {
			tok = token.SUB_ASSIGN
		}
		c.translateStmt(&ast.AssignStmt{
			Lhs: []ast.Expr{s.X},
			Tok: tok,
			Rhs: []ast.Expr{c.newInt(1, t)},
		}, label)

	case *ast.DeclStmt:
		c.printLabel(label)
		decl := s.Decl.(*ast.GenDecl)
		switch decl.Tok {
		case token.VAR:
			for _, spec := range s.Decl.(*ast.GenDecl).Specs {
				valueSpec := spec.(*ast.ValueSpec)
				lhs := make([]ast.Expr, len(valueSpec.Names))
				for i, name := range valueSpec.Names {
					lhs[i] = name
				}
				rhs := valueSpec.Values
				isTuple := false
				if len(rhs) == 1 {
					_, isTuple = c.p.info.Types[rhs[0]].Type.(*types.Tuple)
				}
				for len(rhs) < len(lhs) && !isTuple {
					rhs = append(rhs, nil)
				}
				c.translateStmt(&ast.AssignStmt{
					Lhs: lhs,
					Tok: token.DEFINE,
					Rhs: rhs,
				}, "")
			}
		case token.TYPE:
			for _, spec := range decl.Specs {
				o := c.p.info.Defs[spec.(*ast.TypeSpec).Name].(*types.TypeName)
				c.translateType(o, false)
				c.initType(o)
			}
		case token.CONST:
			// skip, constants are inlined
		}

	case *ast.ExprStmt:
		c.printLabel(label)
		expr := c.translateExpr(s.X)
		if expr != nil {
			c.Printf("%s;", expr)
		}

	case *ast.LabeledStmt:
		c.printLabel(label)
		c.translateStmt(s.Stmt, s.Label.Name)

	case *ast.GoStmt:
		c.printLabel(label)
		c.Printf("$go(%s, [%s]);", c.translateExpr(s.Call.Fun), strings.Join(c.translateArgs(c.p.info.Types[s.Call.Fun].Type.Underlying().(*types.Signature), s.Call.Args, s.Call.Ellipsis.IsValid()), ", "))

	case *ast.SendStmt:
		chanType := c.p.info.Types[s.Chan].Type.Underlying().(*types.Chan)
		call := &ast.CallExpr{
			Fun:  c.newIdent("$send", types.NewSignature(nil, nil, types.NewTuple(types.NewVar(0, nil, "", chanType), types.NewVar(0, nil, "", chanType.Elem())), nil, false)),
			Args: []ast.Expr{s.Chan, s.Value},
		}
		c.blocking[call] = true
		c.translateStmt(&ast.ExprStmt{call}, label)

	case *ast.SelectStmt:
		var channels []string
		var caseClauses []ast.Stmt
		flattened := false
		hasDefault := false
		for i, s := range s.Body.List {
			clause := s.(*ast.CommClause)
			switch comm := clause.Comm.(type) {
			case nil:
				channels = append(channels, "[]")
				hasDefault = true
			case *ast.ExprStmt:
				channels = append(channels, c.formatExpr("[%e]", removeParens(comm.X).(*ast.UnaryExpr).X).String())
			case *ast.AssignStmt:
				channels = append(channels, c.formatExpr("[%e]", removeParens(comm.Rhs[0]).(*ast.UnaryExpr).X).String())
			case *ast.SendStmt:
				channels = append(channels, c.formatExpr("[%e, %e]", comm.Chan, comm.Value).String())
			default:
				panic(fmt.Sprintf("unhandled: %T", comm))
			}
			caseClauses = append(caseClauses, &ast.CaseClause{
				List: []ast.Expr{c.newInt(i, types.Typ[types.Int])},
				Body: clause.Body,
			})
			flattened = flattened || c.flattened[clause]
		}

		selectCall := c.setType(&ast.CallExpr{
			Fun:  c.newIdent("$select", types.NewSignature(nil, nil, types.NewTuple(types.NewVar(0, nil, "", types.NewInterface(nil, nil))), types.NewTuple(types.NewVar(0, nil, "", types.Typ[types.Int])), false)),
			Args: []ast.Expr{c.newIdent(fmt.Sprintf("[%s]", strings.Join(channels, ", ")), types.NewInterface(nil, nil))},
		}, types.Typ[types.Int])
		c.blocking[selectCall] = !hasDefault
		selectionVar := c.newVariable("_selection")
		c.Printf("%s = %s;", selectionVar, c.translateExpr(selectCall))

		translateCond := func(cond ast.Expr) *expression {
			return c.formatExpr("%s[0] === %e", selectionVar, cond)
		}
		printCaseBodyPrefix := func(index int) {
			if assign, ok := s.Body.List[index].(*ast.CommClause).Comm.(*ast.AssignStmt); ok {
				switch rhsType := c.p.info.Types[assign.Rhs[0]].Type.(type) {
				case *types.Tuple:
					c.translateStmt(&ast.AssignStmt{Lhs: assign.Lhs, Rhs: []ast.Expr{c.newIdent(selectionVar+"[1]", rhsType)}, Tok: assign.Tok}, "")
				default:
					c.translateStmt(&ast.AssignStmt{Lhs: assign.Lhs, Rhs: []ast.Expr{c.newIdent(selectionVar+"[1][0]", rhsType)}, Tok: assign.Tok}, "")
				}
			}
		}
		c.translateBranchingStmt(caseClauses, true, translateCond, printCaseBodyPrefix, label, flattened)

	case *ast.EmptyStmt:
		// skip

	default:
		panic(fmt.Sprintf("Unhandled statement: %T\n", s))

	}
}
Exemplo n.º 3
0
func (c *funcContext) translateStmt(stmt ast.Stmt, label string) {
	c.WritePos(stmt.Pos())

	switch s := stmt.(type) {
	case *ast.BlockStmt:
		c.translateStmtList(s.List)

	case *ast.IfStmt:
		c.printLabel(label)
		if s.Init != nil {
			c.translateStmt(s.Init, "")
		}
		var caseClauses []ast.Stmt
		ifStmt := s
		for {
			caseClauses = append(caseClauses, &ast.CaseClause{List: []ast.Expr{ifStmt.Cond}, Body: ifStmt.Body.List})
			switch elseStmt := ifStmt.Else.(type) {
			case *ast.IfStmt:
				if elseStmt.Init != nil {
					caseClauses = append(caseClauses, &ast.CaseClause{List: nil, Body: []ast.Stmt{elseStmt}})
					break
				}
				ifStmt = elseStmt
				continue
			case *ast.BlockStmt:
				caseClauses = append(caseClauses, &ast.CaseClause{List: nil, Body: elseStmt.List})
			case *ast.EmptyStmt, nil:
				// no else clause
			default:
				panic(fmt.Sprintf("Unhandled else: %T\n", elseStmt))
			}
			break
		}
		c.translateBranchingStmt(caseClauses, false, c.translateExpr, nil, "", c.hasGoto[s])

	case *ast.SwitchStmt:
		if s.Init != nil {
			c.translateStmt(s.Init, "")
		}
		translateCond := func(cond ast.Expr) *expression {
			return c.translateExpr(cond)
		}
		if s.Tag != nil {
			refVar := c.newVariable("_ref")
			c.Printf("%s = %s;", refVar, c.translateExpr(s.Tag))
			translateCond = func(cond ast.Expr) *expression {
				refIdent := c.newIdent(refVar, c.p.info.Types[s.Tag].Type)
				return c.translateExpr(&ast.BinaryExpr{
					X:  refIdent,
					Op: token.EQL,
					Y:  cond,
				})
			}
		}
		c.translateBranchingStmt(s.Body.List, true, translateCond, nil, label, c.hasGoto[s])

	case *ast.TypeSwitchStmt:
		if s.Init != nil {
			c.translateStmt(s.Init, "")
		}
		var expr ast.Expr
		var typeSwitchVar string
		switch a := s.Assign.(type) {
		case *ast.AssignStmt:
			expr = a.Rhs[0].(*ast.TypeAssertExpr).X
			typeSwitchVar = c.newVariable(a.Lhs[0].(*ast.Ident).Name)
			for _, caseClause := range s.Body.List {
				c.p.objectVars[c.p.info.Implicits[caseClause]] = typeSwitchVar
			}
		case *ast.ExprStmt:
			expr = a.X.(*ast.TypeAssertExpr).X
		}
		refVar := c.newVariable("_ref")
		typeVar := c.newVariable("_type")
		c.Printf("%s = %s;", refVar, c.translateExpr(expr))
		c.Printf("%s = %s !== null ? %s.constructor : null;", typeVar, refVar, refVar)
		translateCond := func(cond ast.Expr) *expression {
			return c.formatExpr("%s", c.typeCheck(typeVar, c.p.info.Types[cond].Type))
		}
		printCaseBodyPrefix := func(conds []ast.Expr) {
			if typeSwitchVar == "" {
				return
			}
			value := refVar
			if len(conds) == 1 {
				t := c.p.info.Types[conds[0]].Type
				if _, isInterface := t.Underlying().(*types.Interface); !isInterface && !types.Identical(t, types.Typ[types.UntypedNil]) {
					value += ".$val"
				}
			}
			c.Printf("%s = %s;", typeSwitchVar, value)
		}
		c.translateBranchingStmt(s.Body.List, true, translateCond, printCaseBodyPrefix, label, c.hasGoto[s])

	case *ast.ForStmt:
		if s.Init != nil {
			c.translateStmt(s.Init, "")
		}
		cond := "true"
		if s.Cond != nil {
			cond = c.translateExpr(s.Cond).String()
		}
		c.translateLoopingStmt(cond, s.Body, nil, func() {
			if s.Post != nil {
				c.translateStmt(s.Post, "")
			}
		}, label, c.hasGoto[s])

	case *ast.RangeStmt:
		refVar := c.newVariable("_ref")
		c.Printf("%s = %s;", refVar, c.translateExpr(s.X))

		iVar := c.newVariable("_i")
		c.Printf("%s = 0;", iVar)

		switch t := c.p.info.Types[s.X].Type.Underlying().(type) {
		case *types.Basic:
			runeVar := c.newVariable("_rune")
			c.translateLoopingStmt(iVar+" < "+refVar+".length", s.Body, func() {
				c.Printf("%s = $decodeRune(%s, %s);", runeVar, refVar, iVar)
				if !isBlank(s.Key) {
					c.Printf("%s", c.translateAssign(s.Key, iVar, types.Typ[types.Int], s.Tok == token.DEFINE))
				}
				if !isBlank(s.Value) {
					c.Printf("%s", c.translateAssign(s.Value, runeVar+"[0]", types.Typ[types.Rune], s.Tok == token.DEFINE))
				}
			}, func() {
				c.Printf("%s += %s[1];", iVar, runeVar)
			}, label, c.hasGoto[s])

		case *types.Map:
			keysVar := c.newVariable("_keys")
			c.Printf("%s = $keys(%s);", keysVar, refVar)
			c.translateLoopingStmt(iVar+" < "+keysVar+".length", s.Body, func() {
				entryVar := c.newVariable("_entry")
				c.Printf("%s = %s[%s[%s]];", entryVar, refVar, keysVar, iVar)
				if !isBlank(s.Key) {
					c.Printf("%s", c.translateAssign(s.Key, entryVar+".k", t.Key(), s.Tok == token.DEFINE))
				}
				if !isBlank(s.Value) {
					c.Printf("%s", c.translateAssign(s.Value, entryVar+".v", t.Elem(), s.Tok == token.DEFINE))
				}
			}, func() {
				c.Printf("%s++;", iVar)
			}, label, c.hasGoto[s])

		case *types.Array, *types.Pointer, *types.Slice:
			var length string
			var elemType types.Type
			switch t2 := t.(type) {
			case *types.Array:
				length = fmt.Sprintf("%d", t2.Len())
				elemType = t2.Elem()
			case *types.Pointer:
				length = fmt.Sprintf("%d", t2.Elem().Underlying().(*types.Array).Len())
				elemType = t2.Elem().Underlying().(*types.Array).Elem()
			case *types.Slice:
				length = refVar + ".length"
				elemType = t2.Elem()
			}
			c.translateLoopingStmt(iVar+" < "+length, s.Body, func() {
				if !isBlank(s.Key) {
					c.Printf("%s", c.translateAssign(s.Key, iVar, types.Typ[types.Int], s.Tok == token.DEFINE))
				}
				if !isBlank(s.Value) {
					indexExpr := &ast.IndexExpr{
						X:     c.newIdent(refVar, t),
						Index: c.newIdent(iVar, types.Typ[types.Int]),
					}
					c.p.info.Types[indexExpr] = types.TypeAndValue{Type: elemType}
					c.Printf("%s", c.translateAssign(s.Value, c.translateImplicitConversion(indexExpr, elemType).String(), elemType, s.Tok == token.DEFINE))
				}
			}, func() {
				c.Printf("%s++;", iVar)
			}, label, c.hasGoto[s])

		case *types.Chan:
			c.printLabel(label)
			// skip

		default:
			panic("")
		}

	case *ast.BranchStmt:
		c.printLabel(label)
		labelSuffix := ""
		data := c.flowDatas[""]
		if s.Label != nil {
			labelSuffix = " " + s.Label.Name
			data = c.flowDatas[s.Label.Name]
		}
		switch s.Tok {
		case token.BREAK:
			c.PrintCond(data.endCase == 0, fmt.Sprintf("break%s;", labelSuffix), fmt.Sprintf("$s = %d; continue;", data.endCase))
		case token.CONTINUE:
			data.postStmt()
			c.PrintCond(data.beginCase == 0, fmt.Sprintf("continue%s;", labelSuffix), fmt.Sprintf("$s = %d; continue;", data.beginCase))
		case token.GOTO:
			c.PrintCond(false, "goto "+s.Label.Name, fmt.Sprintf("$s = %d; continue;", c.labelCases[s.Label.Name]))
		case token.FALLTHROUGH:
			// handled in CaseClause
		default:
			panic("Unhandled branch statment: " + s.Tok.String())
		}

	case *ast.ReturnStmt:
		c.printLabel(label)
		results := s.Results
		if c.resultNames != nil {
			if len(s.Results) != 0 {
				c.translateStmt(&ast.AssignStmt{
					Lhs: c.resultNames,
					Tok: token.ASSIGN,
					Rhs: s.Results,
				}, "")
			}
			results = c.resultNames
		}
		switch len(results) {
		case 0:
			c.Printf("return;")
		case 1:
			if c.sig.Results().Len() > 1 {
				c.Printf("return %s;", c.translateExpr(results[0]))
				break
			}
			v := c.translateImplicitConversion(results[0], c.sig.Results().At(0).Type())
			c.delayedOutput = nil
			c.Printf("return %s;", v)
		default:
			values := make([]string, len(results))
			for i, result := range results {
				values[i] = c.translateImplicitConversion(result, c.sig.Results().At(i).Type()).String()
			}
			c.delayedOutput = nil
			c.Printf("return [%s];", strings.Join(values, ", "))
		}

	case *ast.DeferStmt:
		c.printLabel(label)
		isBuiltin := false
		isJs := false
		switch fun := s.Call.Fun.(type) {
		case *ast.Ident:
			var builtin *types.Builtin
			builtin, isBuiltin = c.p.info.Uses[fun].(*types.Builtin)
			if isBuiltin && builtin.Name() == "recover" {
				c.Printf("$deferred.push({ fun: $recover, args: [] });")
				return
			}
		case *ast.SelectorExpr:
			isJs = isJsPackage(c.p.info.Uses[fun.Sel].Pkg())
		}
		if isBuiltin || isJs {
			args := make([]ast.Expr, len(s.Call.Args))
			for i, arg := range s.Call.Args {
				args[i] = c.newIdent(c.newVariable("_arg"), c.p.info.Types[arg].Type)
			}
			call := c.translateExpr(&ast.CallExpr{
				Fun:      s.Call.Fun,
				Args:     args,
				Ellipsis: s.Call.Ellipsis,
			})
			c.Printf("$deferred.push({ fun: function(%s) { %s; }, args: [%s] });", strings.Join(c.translateExprSlice(args, nil), ", "), call, strings.Join(c.translateExprSlice(s.Call.Args, nil), ", "))
			return
		}
		sig := c.p.info.Types[s.Call.Fun].Type.Underlying().(*types.Signature)
		args := strings.Join(c.translateArgs(sig, s.Call.Args, s.Call.Ellipsis.IsValid()), ", ")
		if s, isSelector := s.Call.Fun.(*ast.SelectorExpr); isSelector {
			obj := c.p.info.Uses[s.Sel]
			if !obj.Exported() {
				c.p.dependencies[obj] = true
			}
			recv := c.translateExpr(s.X)
			sel, ok := c.p.info.Selections[s]
			if ok && sel.Kind() == types.MethodVal && isWrapped(sel.Recv()) {
				recv = c.formatParenExpr("new %s(%s)", c.typeName(sel.Recv()), recv)
			}
			c.Printf(`$deferred.push({ recv: %s, method: "%s", args: [%s] });`, recv, s.Sel.Name, args)
			return
		}
		c.Printf("$deferred.push({ fun: %s, args: [%s] });", c.translateExpr(s.Call.Fun), args)

	case *ast.AssignStmt:
		c.printLabel(label)
		if s.Tok != token.ASSIGN && s.Tok != token.DEFINE {
			var op token.Token
			switch s.Tok {
			case token.ADD_ASSIGN:
				op = token.ADD
			case token.SUB_ASSIGN:
				op = token.SUB
			case token.MUL_ASSIGN:
				op = token.MUL
			case token.QUO_ASSIGN:
				op = token.QUO
			case token.REM_ASSIGN:
				op = token.REM
			case token.AND_ASSIGN:
				op = token.AND
			case token.OR_ASSIGN:
				op = token.OR
			case token.XOR_ASSIGN:
				op = token.XOR
			case token.SHL_ASSIGN:
				op = token.SHL
			case token.SHR_ASSIGN:
				op = token.SHR
			case token.AND_NOT_ASSIGN:
				op = token.AND_NOT
			default:
				panic(s.Tok)
			}

			var parts []string
			lhs := s.Lhs[0]
			switch l := lhs.(type) {
			case *ast.IndexExpr:
				lhsVar := c.newVariable("_lhs")
				indexVar := c.newVariable("_index")
				parts = append(parts, lhsVar+" = "+c.translateExpr(l.X).String()+";")
				parts = append(parts, indexVar+" = "+c.translateExpr(l.Index).String()+";")
				lhs = &ast.IndexExpr{
					X:     c.newIdent(lhsVar, c.p.info.Types[l.X].Type),
					Index: c.newIdent(indexVar, c.p.info.Types[l.Index].Type),
				}
				c.p.info.Types[lhs] = c.p.info.Types[l]
			case *ast.StarExpr:
				lhsVar := c.newVariable("_lhs")
				parts = append(parts, lhsVar+" = "+c.translateExpr(l.X).String()+";")
				lhs = &ast.StarExpr{
					X: c.newIdent(lhsVar, c.p.info.Types[l.X].Type),
				}
				c.p.info.Types[lhs] = c.p.info.Types[l]
			case *ast.SelectorExpr:
				v := hasCallVisitor{c.p.info, false}
				ast.Walk(&v, l.X)
				if v.hasCall {
					lhsVar := c.newVariable("_lhs")
					parts = append(parts, lhsVar+" = "+c.translateExpr(l.X).String()+";")
					lhs = &ast.SelectorExpr{
						X:   c.newIdent(lhsVar, c.p.info.Types[l.X].Type),
						Sel: l.Sel,
					}
					c.p.info.Types[lhs] = c.p.info.Types[l]
					c.p.info.Selections[lhs.(*ast.SelectorExpr)] = c.p.info.Selections[l]
				}
			}

			parenExpr := &ast.ParenExpr{X: s.Rhs[0]}
			c.p.info.Types[parenExpr] = c.p.info.Types[s.Rhs[0]]
			binaryExpr := &ast.BinaryExpr{
				X:  lhs,
				Op: op,
				Y:  parenExpr,
			}
			lhsType := c.p.info.Types[s.Lhs[0]]
			c.p.info.Types[binaryExpr] = lhsType
			parts = append(parts, c.translateAssign(lhs, c.translateExpr(binaryExpr).String(), lhsType.Type, s.Tok == token.DEFINE))
			c.Printf("%s", strings.Join(parts, " "))
			return
		}

		if s.Tok == token.DEFINE {
			for _, lhs := range s.Lhs {
				if !isBlank(lhs) {
					obj := c.p.info.Defs[lhs.(*ast.Ident)]
					if obj == nil {
						obj = c.p.info.Uses[lhs.(*ast.Ident)]
					}
					c.p.info.Types[lhs] = types.TypeAndValue{Type: obj.Type()}
				}
			}
		}

		switch {
		case len(s.Lhs) == 1 && len(s.Rhs) == 1:
			lhs := removeParens(s.Lhs[0])
			if isBlank(lhs) {
				v := hasCallVisitor{c.p.info, false}
				ast.Walk(&v, s.Rhs[0])
				if v.hasCall {
					c.Printf("%s;", c.translateExpr(s.Rhs[0]).String())
				}
				return
			}
			lhsType := c.p.info.Types[s.Lhs[0]].Type
			c.Printf("%s", c.translateAssign(lhs, c.translateImplicitConversion(s.Rhs[0], lhsType).String(), lhsType, s.Tok == token.DEFINE))

		case len(s.Lhs) > 1 && len(s.Rhs) == 1:
			tupleVar := c.newVariable("_tuple")
			out := tupleVar + " = " + c.translateExpr(s.Rhs[0]).String() + ";"
			tuple := c.p.info.Types[s.Rhs[0]].Type.(*types.Tuple)
			for i, lhs := range s.Lhs {
				lhs = removeParens(lhs)
				if !isBlank(lhs) {
					lhsType := c.p.info.Types[s.Lhs[i]].Type
					out += " " + c.translateAssign(lhs, c.translateImplicitConversion(c.newIdent(fmt.Sprintf("%s[%d]", tupleVar, i), tuple.At(i).Type()), lhsType).String(), lhsType, s.Tok == token.DEFINE)
				}
			}
			c.Printf("%s", out)
		case len(s.Lhs) == len(s.Rhs):
			tmpVars := make([]string, len(s.Rhs))
			var parts []string
			for i, rhs := range s.Rhs {
				tmpVars[i] = c.newVariable("_tmp")
				if isBlank(removeParens(s.Lhs[i])) {
					v := hasCallVisitor{c.p.info, false}
					ast.Walk(&v, rhs)
					if v.hasCall {
						c.Printf("%s;", c.translateExpr(rhs).String())
					}
					continue
				}
				lhsType := c.p.info.Types[s.Lhs[i]].Type
				parts = append(parts, c.translateAssign(c.newIdent(tmpVars[i], c.p.info.Types[s.Lhs[i]].Type), c.translateImplicitConversion(rhs, lhsType).String(), lhsType, true))
			}
			for i, lhs := range s.Lhs {
				lhs = removeParens(lhs)
				if !isBlank(lhs) {
					parts = append(parts, c.translateAssign(lhs, tmpVars[i], c.p.info.Types[lhs].Type, s.Tok == token.DEFINE))
				}
			}
			c.Printf("%s", strings.Join(parts, " "))

		default:
			panic("Invalid arity of AssignStmt.")

		}

	case *ast.IncDecStmt:
		t := c.p.info.Types[s.X].Type
		if iExpr, isIExpr := s.X.(*ast.IndexExpr); isIExpr {
			switch u := c.p.info.Types[iExpr.X].Type.Underlying().(type) {
			case *types.Array:
				t = u.Elem()
			case *types.Slice:
				t = u.Elem()
			case *types.Map:
				t = u.Elem()
			}
		}

		tok := token.ADD_ASSIGN
		if s.Tok == token.DEC {
			tok = token.SUB_ASSIGN
		}
		one := &ast.BasicLit{
			Kind:  token.INT,
			Value: "1",
		}
		c.p.info.Types[one] = types.TypeAndValue{Type: t, Value: exact.MakeInt64(1)}
		c.translateStmt(&ast.AssignStmt{
			Lhs: []ast.Expr{s.X},
			Tok: tok,
			Rhs: []ast.Expr{one},
		}, label)

	case *ast.ExprStmt:
		c.printLabel(label)
		c.Printf("%s;", c.translateExpr(s.X).String())

	case *ast.DeclStmt:
		c.printLabel(label)
		decl := s.Decl.(*ast.GenDecl)
		switch decl.Tok {
		case token.VAR:
			for _, spec := range s.Decl.(*ast.GenDecl).Specs {
				valueSpec := spec.(*ast.ValueSpec)
				lhs := make([]ast.Expr, len(valueSpec.Names))
				for i, name := range valueSpec.Names {
					lhs[i] = name
				}
				rhs := valueSpec.Values
				isTuple := false
				if len(rhs) == 1 {
					_, isTuple = c.p.info.Types[rhs[0]].Type.(*types.Tuple)
				}
				for len(rhs) < len(lhs) && !isTuple {
					rhs = append(rhs, nil)
				}
				c.translateStmt(&ast.AssignStmt{
					Lhs: lhs,
					Tok: token.DEFINE,
					Rhs: rhs,
				}, "")
			}
		case token.TYPE:
			for _, spec := range decl.Specs {
				o := c.p.info.Defs[spec.(*ast.TypeSpec).Name].(*types.TypeName)
				c.translateType(o, false)
				c.initType(o)
			}
		case token.CONST:
			// skip, constants are inlined
		}

	case *ast.LabeledStmt:
		c.printLabel(label)
		c.translateStmt(s.Stmt, s.Label.Name)

	case *ast.SelectStmt:
		c.printLabel(label)
		c.Printf(`$notSupported("select");`)

	case *ast.GoStmt:
		c.printLabel(label)
		c.Printf(`$notSupported("go");`)

	case *ast.SendStmt:
		c.printLabel(label)
		c.Printf(`$notSupported("send");`)

	case *ast.EmptyStmt:
		// skip

	default:
		panic(fmt.Sprintf("Unhandled statement: %T\n", s))

	}
}
Exemplo n.º 4
0
func (cdd *CDD) builtin(b *types.Builtin, args []ast.Expr) (fun, recv string) {
	name := b.Name()

	switch name {
	case "len":
		switch t := underlying(cdd.exprType(args[0])).(type) {
		case *types.Slice, *types.Basic: // Basic == String
			return "len", ""

		case *types.Array:
			return "", strconv.FormatInt(t.Len(), 10)

		case *types.Chan:
			return "clen", ""

		default:
			notImplemented(ast.NewIdent("len"), t)
		}

	case "cap":
		switch t := underlying(cdd.exprType(args[0])).(type) {
		case *types.Slice:
			return "cap", ""

		case *types.Chan:
			return "ccap", ""

		default:
			notImplemented(ast.NewIdent("cap"), t)
		}

	case "copy":
		switch t := underlying(cdd.exprType(args[1])).(type) {
		case *types.Basic: // string
			return "STRCPY", ""

		case *types.Slice:
			typ, dim, _ := cdd.TypeStr(t.Elem())
			return "SLICPY", typ + dimFuncPtr("", dim)

		default:
			panic(t)
		}

	case "new":
		typ, dim, _ := cdd.TypeStr(cdd.exprType(args[0]))
		args[0] = nil
		return "NEW", typ + dimFuncPtr("", dim)

	case "make":
		a0t := cdd.exprType(args[0])
		args[0] = nil

		switch t := underlying(a0t).(type) {
		case *types.Slice:
			typ, dim, _ := cdd.TypeStr(t.Elem())
			name := "MAKESLI"
			if len(args) == 3 {
				name = "MAKESLIC"
			}
			return name, typ + dimFuncPtr("", dim)

		case *types.Chan:
			typ, dim, _ := cdd.TypeStr(t.Elem())
			typ += dimFuncPtr("", dim)
			if len(args) == 1 {
				typ += ", 0"
			}
			return "MAKECHAN", typ

		case *types.Map:
			typ, dim, _ := cdd.TypeStr(t.Key())
			k := typ + dimFuncPtr("", dim)
			typ, dim, _ = cdd.TypeStr(t.Elem())
			e := typ + dimFuncPtr("", dim)
			name := "MAKEMAP"
			if len(args) == 2 {
				name = "MAKEMAPC"
			}
			return name, k + ", " + e

		default:
			notImplemented(ast.NewIdent(name))
		}

	}

	return name, ""
}