Golang types.NewVar函数代码示例

func (m *TypeMap) descriptorInterface(t *types.Interface, name string) TypeDebugDescriptor {
	ifaceStruct := types.NewStruct([]*types.Var{
		types.NewVar(0, nil, "type", types.NewPointer(types.Typ[types.Uint8])),
		types.NewVar(0, nil, "data", types.NewPointer(types.Typ[types.Uint8])),
	}, nil)
	return m.typeDebugDescriptor(ifaceStruct, name)
}

func (m *TypeMap) descriptorSlice(t *types.Slice, name string) TypeDebugDescriptor {
	sliceStruct := types.NewStruct([]*types.Var{
		types.NewVar(0, nil, "ptr", types.NewPointer(t.Elem())),
		types.NewVar(0, nil, "len", types.Typ[types.Int]),
		types.NewVar(0, nil, "cap", types.Typ[types.Int]),
	}, nil)
	return m.typeDebugDescriptor(sliceStruct, name)
}

func (c *PkgContext) loadStruct(array, target string, s *types.Struct) {
	view := c.newVariable("_view")
	c.Printf("%s = new DataView(%s.buffer, %s.byteOffset);", view, array, array)
	var fields []*types.Var
	var collectFields func(s *types.Struct, path string)
	collectFields = func(s *types.Struct, path string) {
		for i := 0; i < s.NumFields(); i++ {
			field := s.Field(i)
			if fs, isStruct := field.Type().Underlying().(*types.Struct); isStruct {
				collectFields(fs, path+"."+field.Name())
				continue
			}
			fields = append(fields, types.NewVar(0, nil, path+"."+field.Name(), field.Type()))
		}
	}
	collectFields(s, target)
	offsets := sizes32.Offsetsof(fields)
	for i, field := range fields {
		switch t := field.Type().Underlying().(type) {
		case *types.Basic:
			if t.Info()&types.IsNumeric != 0 {
				if is64Bit(t) {
					c.Printf("%s = new %s(%s.getUint32(%d, true), %s.getUint32(%d, true));", field.Name(), c.typeName(field.Type()), view, offsets[i]+4, view, offsets[i])
					continue
				}
				c.Printf("%s = %s.get%s(%d, true);", field.Name(), view, toJavaScriptType(t), offsets[i])
			}
			continue
		case *types.Array:
			c.Printf("%s = new %s(%s.buffer, Go$min(%s.byteOffset + %d, %s.buffer.byteLength));", field.Name(), toArrayType(t.Elem()), array, array, offsets[i], array)
			continue
		}
		c.Printf("// skipped: %s %s", field.Name(), field.Type().String())
	}
}

func (c *funcContext) loadStruct(array, target string, s *types.Struct) string {
	view := c.newVariable("_view")
	code := fmt.Sprintf("%s = new DataView(%s.buffer, %s.byteOffset)", view, array, array)
	var fields []*types.Var
	var collectFields func(s *types.Struct, path string)
	collectFields = func(s *types.Struct, path string) {
		for i := 0; i < s.NumFields(); i++ {
			field := s.Field(i)
			if fs, isStruct := field.Type().Underlying().(*types.Struct); isStruct {
				collectFields(fs, path+"."+fieldName(s, i))
				continue
			}
			fields = append(fields, types.NewVar(0, nil, path+"."+fieldName(s, i), field.Type()))
		}
	}
	collectFields(s, target)
	offsets := sizes32.Offsetsof(fields)
	for i, field := range fields {
		switch t := field.Type().Underlying().(type) {
		case *types.Basic:
			if t.Info()&types.IsNumeric != 0 {
				if is64Bit(t) {
					code += fmt.Sprintf(", %s = new %s(%s.getUint32(%d, true), %s.getUint32(%d, true))", field.Name(), c.typeName(field.Type()), view, offsets[i]+4, view, offsets[i])
					break
				}
				code += fmt.Sprintf(", %s = %s.get%s(%d, true)", field.Name(), view, toJavaScriptType(t), offsets[i])
			}
		case *types.Array:
			code += fmt.Sprintf(`, %s = new ($nativeArray("%s"))(%s.buffer, $min(%s.byteOffset + %d, %s.buffer.byteLength))`, field.Name(), typeKind(t.Elem()), array, array, offsets[i], array)
		}
	}
	return code
}

func (c *PkgContext) newIdent(name string, t types.Type) *ast.Ident {
	ident := ast.NewIdent(name)
	c.info.Types[ident] = t
	obj := types.NewVar(0, c.pkg, name, t)
	c.info.Objects[ident] = obj
	c.objectVars[obj] = name
	return ident
}

func (c *funcContext) newIdent(name string, t types.Type) *ast.Ident {
	ident := ast.NewIdent(name)
	c.setType(ident, t)
	obj := types.NewVar(0, c.p.pkg, name, t)
	c.p.info.Uses[ident] = obj
	c.p.objectVars[obj] = name
	return ident
}

// promoteMethod promotes a named type's method to another type
// which has embedded the named type.
func (c *compiler) promoteMethod(m *types.Func, recv types.Type, indices []int) types.Object {
	var pkg *types.Package
	if recv, ok := recv.(*types.Named); ok {
		pkg = c.objectdata[recv.Obj()].Package
	}
	recvvar := types.NewVar(pkg, "", recv)
	sig := m.Type().(*types.Signature)
	sig = types.NewSignature(recvvar, sig.Params(), sig.Results(), sig.IsVariadic())
	f := &synthFunc{pkg: pkg, name: m.Name(), typ: sig}
	ident := ast.NewIdent(f.Name())

	var isptr bool
	if ptr, ok := recv.(*types.Pointer); ok {
		isptr = true
		recv = ptr.Elem()
	}

	c.objects[ident] = f
	c.objectdata[f] = &ObjectData{Ident: ident, Package: pkg}

	if pkg == nil || pkg == c.pkg {
		if currblock := c.builder.GetInsertBlock(); !currblock.IsNil() {
			defer c.builder.SetInsertPointAtEnd(currblock)
		}
		llvmfn := c.Resolve(ident).LLVMValue()
		llvmfn = c.builder.CreateExtractValue(llvmfn, 0, "")
		llvmfn.SetLinkage(llvm.LinkOnceODRLinkage)
		entry := llvm.AddBasicBlock(llvmfn, "entry")
		c.builder.SetInsertPointAtEnd(entry)

		realfn := c.Resolve(c.objectdata[m].Ident).LLVMValue()
		realfn = c.builder.CreateExtractValue(realfn, 0, "")

		args := llvmfn.Params()
		recvarg := args[0]
		if !isptr {
			ptr := c.builder.CreateAlloca(recvarg.Type(), "")
			c.builder.CreateStore(recvarg, ptr)
			recvarg = ptr
		}
		for _, i := range indices {
			if i == -1 {
				recvarg = c.builder.CreateLoad(recvarg, "")
			} else {
				recvarg = c.builder.CreateStructGEP(recvarg, i, "")
			}
		}

		args[0] = recvarg
		result := c.builder.CreateCall(realfn, args, "")
		if sig.Results().Len() == 0 {
			c.builder.CreateRetVoid()
		} else {
			c.builder.CreateRet(result)
		}
	}
	return f
}

func (m *TypeMap) descriptorBasic(t *types.Basic, name string) TypeDebugDescriptor {
	switch t.Kind() {
	case types.String:
		return m.descriptorStruct(types.NewStruct([]*types.Var{
			types.NewVar(0, nil, "ptr", types.NewPointer(types.Typ[types.Uint8])),
			types.NewVar(0, nil, "len", types.Typ[types.Int]),
		}, nil), name)
	case types.UnsafePointer:
		return &BasicTypeDescriptor{
			TypeDescriptorCommon: TypeDescriptorCommon{
				Name:      name,
				Size:      uint64(m.Sizes.Sizeof(t) * 8),
				Alignment: uint64(m.Sizes.Alignof(t) * 8),
			},
			TypeEncoding: DW_ATE_unsigned,
		}
	default:
		bt := &BasicTypeDescriptor{
			TypeDescriptorCommon: TypeDescriptorCommon{
				Name:      t.String(),
				Size:      uint64(m.Sizes.Sizeof(t) * 8),
				Alignment: uint64(m.Sizes.Alignof(t) * 8),
			},
		}
		switch bi := t.Info(); {
		case bi&types.IsBoolean != 0:
			bt.TypeEncoding = DW_ATE_boolean
		case bi&types.IsUnsigned != 0:
			bt.TypeEncoding = DW_ATE_unsigned
		case bi&types.IsInteger != 0:
			bt.TypeEncoding = DW_ATE_signed
		case bi&types.IsFloat != 0:
			bt.TypeEncoding = DW_ATE_float
		case bi&types.IsComplex != 0:
			bt.TypeEncoding = DW_ATE_imaginary_float
		case bi&types.IsUnsigned != 0:
			bt.TypeEncoding = DW_ATE_unsigned
		default:
			panic(fmt.Sprintf("unhandled: %#v", t))
		}
		return bt
	}
}

// newMethod creates a new method of the specified name, package and receiver type.
func newMethod(pkg *ssa.Package, recvType types.Type, name string) *ssa.Function {
	// TODO(adonovan): fix: hack: currently the only part of Signature
	// that is needed is the "pointerness" of Recv.Type, and for
	// now, we'll set it to always be false since we're only
	// concerned with rtype.  Encapsulate this better.
	sig := types.NewSignature(nil, types.NewVar(token.NoPos, nil, "recv", recvType), nil, nil, false)
	fn := pkg.Prog.NewFunction(name, sig, "fake reflect method")
	fn.Pkg = pkg
	return fn
}

// newMethod creates a new method of the specified name, package and receiver type.
func newMethod(pkg *ssa.Package, recvType types.Type, name string) *ssa.Function {
	fn := &ssa.Function{
		Name_: name,
		Pkg:   pkg,
		Prog:  pkg.Prog,
	}
	// TODO(adonovan): fix: hack: currently the only part of Signature
	// that is needed is the "pointerness" of Recv.Type, and for
	// now, we'll set it to always be false since we're only
	// concerned with rtype.  Encapsulate this better.
	fn.Signature = types.NewSignature(types.NewVar(nil, "recv", recvType), nil, nil, false)
	return fn
}

// emitTypeTest emits to f a type test value,ok := x.(t) and returns
// a (value, ok) tuple.  x.Type() must be an interface.
//
func emitTypeTest(f *Function, x Value, t types.Type, pos token.Pos) Value {
	a := &TypeAssert{
		X:            x,
		AssertedType: t,
		CommaOk:      true,
	}
	a.setPos(pos)
	a.setType(types.NewTuple(
		types.NewVar(token.NoPos, nil, "value", t),
		varOk,
	))
	return f.emit(a)
}

// emitTypeTest emits to f a type test value,ok := x.(t) and returns
// a (value, ok) tuple.  x.Type() must be an interface.
//
func emitTypeTest(f *Function, x Value, t types.Type) Value {
	// TODO(adonovan): opt: simplify infallible tests as per
	// emitTypeAssert, and return (x, vTrue).
	// (Requires that exprN returns a slice of extracted values,
	// not a single Value of type *types.Results.)
	a := &TypeAssert{
		X:            x,
		AssertedType: t,
		CommaOk:      true,
	}
	a.setType(types.NewTuple(
		types.NewVar(nil, "value", t),
		varOk,
	))
	return f.emit(a)
}

func (p *importer) obj(pkg *types.Package) {
	var obj types.Object
	switch tag := p.int(); tag {
	case constTag:
		obj = types.NewConst(token.NoPos, pkg, p.string(), p.typ(), p.value())
	case typeTag:
		// type object is added to scope via respective named type
		_ = p.typ().(*types.Named)
		return
	case varTag:
		obj = types.NewVar(token.NoPos, pkg, p.string(), p.typ())
	case funcTag:
		obj = types.NewFunc(token.NoPos, pkg, p.string(), p.typ().(*types.Signature))
	default:
		panic(fmt.Sprintf("unexpected object tag %d", tag))
	}

	if alt := pkg.Scope().Insert(obj); alt != nil {
		panic(fmt.Sprintf("%s already declared", alt.Name()))
	}
}

// Parameter = ( identifier | "?" ) [ "..." ] Type [ string_lit ] .
//
func (p *parser) parseParameter() (par *types.Var, isVariadic bool) {
	_, name := p.parseName(false)
	if name == "" {
		name = "_" // cannot access unnamed identifiers
	}
	if p.tok == '.' {
		p.expectSpecial("...")
		isVariadic = true
	}
	typ := p.parseType()
	if isVariadic {
		typ = types.NewSlice(typ)
	}
	// ignore argument tag (e.g. "noescape")
	if p.tok == scanner.String {
		p.next()
	}
	// TODO(gri) should we provide a package?
	par = types.NewVar(token.NoPos, nil, name, typ)
	return
}

// Parameter = ( identifier | "?" ) [ "..." ] Type [ string_lit ] .
//
func (p *parser) parseParameter() (par *types.Var, isVariadic bool) {
	_, name := p.parseName(false)
	// remove gc-specific parameter numbering
	if i := strings.Index(name, "·"); i >= 0 {
		name = name[:i]
	}
	if p.tok == '.' {
		p.expectSpecial("...")
		isVariadic = true
	}
	typ := p.parseType()
	if isVariadic {
		typ = types.NewSlice(typ)
	}
	// ignore argument tag (e.g. "noescape")
	if p.tok == scanner.String {
		p.next()
	}
	// TODO(gri) should we provide a package?
	par = types.NewVar(token.NoPos, nil, name, typ)
	return
}