func checkNoSideEffects(x *cc.Expr, mode int) {
var before, after []*cc.Stmt
old := x.String()
doSideEffects(x, &before, &after, mode)
if len(before)+len(after) > 0 {
fprintf(x.Span, "cannot handle side effects in %s", old)
}
}
func fixMerge(dst, src *cc.Expr) {
syn := dst.SyntaxInfo
syn.Comments.Before = append(syn.Comments.Before, src.Comments.Before...)
syn.Comments.After = append(syn.Comments.After, src.Comments.After...)
syn.Comments.Suffix = append(syn.Comments.Suffix, src.Comments.Suffix...)
*dst = *src
dst.SyntaxInfo = syn
}
func matchSize(fn *cc.Decl, obj *cc.Expr, objType *cc.Type, siz *cc.Expr) bool {
switch siz.Op {
default:
return false
case cc.SizeofType:
// ok if sizeof type of first arg
return sameType(siz.Type, objType)
case cc.SizeofExpr:
// ok if sizeof *firstarg
y := siz.Left
if y.Op == cc.Paren {
y = y.Left
}
return obj.String() == y.String()
}
}
func tryPrintf(curfn *cc.Decl, x *cc.Expr, name string, fmtpos int, newName string) bool {
if (x.Left.Text == name || (strings.Contains(name, ".") || strings.Contains(name, "->")) && x.Left.String() == name) && len(x.List) >= fmtpos+1 && x.List[fmtpos].Op == cc.String {
x.List = append(x.List[:fmtpos+1], fixPrintFormat(curfn, x.List[fmtpos], x.List[fmtpos+1:])...)
if newName != "" {
x.Left.Text = newName
x.Left.XDecl = nil
}
return true
}
return false
}
func fixPrintf(curfn *cc.Decl, x *cc.Expr) bool {
if x.Op != cc.Call {
return false
}
if tryPrintf(curfn, x, "sprint", 1, "fmt.Sprintf") {
targ := x.List[0]
x.List = x.List[1:]
x.Right = copyExpr(x)
x.List = nil
x.Left = targ
x.Op = cc.Eq
// sprint(strchr(s, 0), "hello") => s += "hello"
if targ.Op == cc.Call && len(targ.List) == 2 && targ.Left.Text == "strchr" && targ.List[1].Text == "0" {
x.Left = targ.List[0]
x.Op = cc.AddEq
} else if targ.Op == cc.Add && targ.Right.Op == cc.Call && targ.Right.Left.Text == "strlen" && len(targ.Right.List) == 1 && GoString(targ.Left) == GoString(targ.Right.List[0]) {
x.Left = targ.Left
x.Op = cc.AddEq
}
return true
}
if tryPrintf(curfn, x, "snprint", 2, "fmt.Sprintf") {
targ := x.List[0]
x.List = x.List[2:]
x.Right = copyExpr(x)
x.List = nil
x.Left = targ
x.Op = cc.Eq
return true
}
if tryPrintf(curfn, x, "fmtprint", 1, "fmt.Sprintf") {
targ := x.List[0]
x.List = x.List[1:]
x.Right = copyExpr(x)
x.List = nil
x.Left = targ
x.Op = cc.AddEq
if x.Left.Op == cc.Addr {
x.Left = x.Left.Left
}
return true
}
if tryPrintf(curfn, x, "smprint", 0, "fmt.Sprintf") {
x.XType = stringType
return true
}
if tryPrintf(curfn, x, "print", 0, "fmt.Printf") {
return true
}
if tryPrintf(curfn, x, "fprint", 1, "fmt.Fprintf") {
if x.List[0].String() == "2" {
x.List[0] = &cc.Expr{Op: cc.Name, Text: "os.Stderr"}
}
return true
}
if tryPrintf(curfn, x, "sysfatal", 0, "log.Fatalf") {
return true
}
if tryPrintf(curfn, x, "fatal", 0, "") {
return true
}
if tryPrintf(curfn, x, "ctxt->diag", 0, "") {
return true
}
if tryPrintf(curfn, x, "diag", 0, "") {
return true
}
if tryPrintf(curfn, x, "werrstr", 0, "") {
return true
}
if tryPrintf(curfn, x, "yyerror", 0, "") {
return true
}
if tryPrintf(curfn, x, "yyerrorl", 1, "") {
forceConvert(curfn, x.List[0], x.List[0].XType, intType)
return true
}
if tryPrintf(curfn, x, "onearg", 1, "") {
return true
}
if tryPrintf(curfn, x, "warn", 0, "") {
return true
}
if tryPrintf(curfn, x, "warnl", 1, "") {
forceConvert(curfn, x.List[0], x.List[0].XType, intType)
return true
}
if tryPrintf(curfn, x, "Bprint", 1, "fmt.Fprintf") {
return true
}
if isCall(x, "exprfmt") && len(x.List) == 3 {
// exprfmt(fp, x, y) becomes fp += exprfmt(x, y)
x.Op = cc.AddEq
x.Right = &cc.Expr{Op: cc.Call, Left: x.Left, List: x.List[1:]}
x.Left = x.List[0]
x.List = nil
x.XType = stringType
return true
}
if isCall(x, "fmtstrinit") && len(x.List) == 1 && x.List[0].Op == cc.Addr {
x.Op = cc.Eq
x.Left = x.List[0].Left
x.List = nil
x.Right = &cc.Expr{Op: cc.Name, Text: `""`}
}
if isCall(x, "fmtstrflush") && len(x.List) == 1 && x.List[0].Op == cc.Addr {
x.Op = cc.Paren
x.Left = x.List[0].Left
x.List = nil
}
return false
}
func fixSpecialCall(fn *cc.Decl, x *cc.Expr, targ *cc.Type) bool {
if x.Left.Op != cc.Name {
return false
}
switch x.Left.Text {
case "memmove":
if len(x.List) != 3 {
// fprintf(x.Span, "unsupported %v", x)
return false
}
siz := x.List[2]
if siz.Op == cc.Number && siz.Text == "4" {
obj1, obj1Type := objIndir(fn, x.List[0])
obj2, obj2Type := objIndir(fn, x.List[1])
if obj1Type == nil || obj2Type == nil {
// fprintf(x.Span, "unsupported %v - missing types", x)
return true
}
if (obj1Type.Kind == Uint32 || obj1Type.Kind == Int32) && obj2Type.Kind == Float32 {
x.Op = cc.Eq
x.Left = obj1
x.Right = &cc.Expr{
Op: cc.Call,
Left: &cc.Expr{Op: cc.Name,
Text: "math.Float32bits",
},
List: []*cc.Expr{obj2},
}
x.XType = uint32Type
return true
}
// fprintf(x.Span, "unsupported %v - size 4 type %v %v", x, GoString(obj1Type), GoString(obj2Type))
}
if siz.Op == cc.Number && siz.Text == "8" {
obj1, obj1Type := objIndir(fn, x.List[0])
obj2, obj2Type := objIndir(fn, x.List[1])
if obj1Type == nil || obj2Type == nil {
// fprintf(x.Span, "unsupported %v - missing types", x)
return true
}
if (obj1Type.Kind == Uint64 || obj1Type.Kind == Int64) && obj2Type.Kind == Float64 {
x.Op = cc.Eq
x.Left = obj1
x.Right = &cc.Expr{
Op: cc.Call,
Left: &cc.Expr{Op: cc.Name,
Text: "math.Float64bits",
},
List: []*cc.Expr{obj2},
}
x.XType = uint64Type
return true
}
// fprintf(x.Span, "unsupported %v - size 8 type %v %v", x, GoString(obj1Type), GoString(obj2Type))
}
if siz.Op == cc.SizeofExpr {
obj1Type := fixGoTypesExpr(fn, x.List[0], nil)
obj2Type := fixGoTypesExpr(fn, x.List[1], nil)
sizeType := fixGoTypesExpr(fn, siz.Left, nil)
if obj1Type == nil || obj2Type == nil {
// fprintf(x.Span, "unsupported %v - bad types", x)
return true
}
if obj2Type.Kind == cc.Array && sameType(obj2Type, sizeType) || obj2Type.Kind == Slice && GoString(x.List[1]) == GoString(siz.Left) {
x.Left.Text = "copy"
x.Left.XDecl = nil
x.List = x.List[:2]
return true
}
// fprintf(x.Span, "unsupported %v - not array %v %v", x, GoString(obj2Type), GoString(sizeType))
return true
}
left := fixGoTypesExpr(fn, x.List[0], nil)
right := fixGoTypesExpr(fn, x.List[1], nil)
fixGoTypesExpr(fn, siz, nil)
if isSliceOrArray(left) && isSliceOrArray(right) && left.Base.Is(Uint8) && right.Base.Is(Uint8) {
x.Left.Text = "copy"
x.Left.XDecl = nil
if x.List[1].Op == ExprSlice && x.List[1].List[1] == nil {
x.List[1].List[2] = siz
} else {
x.List[1] = &cc.Expr{Op: ExprSlice, List: []*cc.Expr{x.List[1], nil, siz}}
}
x.List = x.List[:2]
return true
}
// fprintf(x.Span, "unsupported %v (%v %v)", x, GoString(left), GoString(right))
return true
case "mal", "malloc", "emallocz", "xmalloc":
if len(x.List) != 1 {
fprintf(x.Span, "unsupported %v - too many args", x)
return false
}
siz := x.List[0]
var count *cc.Expr
if siz.Op == cc.Mul {
count = siz.Left
siz = siz.Right
if count.Op == cc.SizeofType || count.Op == cc.SizeofExpr {
count, siz = siz, count
}
}
var typ *cc.Type
switch siz.Op {
default:
typ = byteType
count = siz
case cc.SizeofExpr:
typ = fixGoTypesExpr(fn, siz.Left, nil)
if typ == nil {
fprintf(siz.Span, "failed to type check %v", siz.Left)
}
case cc.SizeofType:
typ = siz.Type
if typ == nil {
fprintf(siz.Span, "sizeoftype missing type")
}
}
if typ == nil {
fprintf(x.Span, "unsupported %v - cannot understand type", x)
return true
}
if count == nil {
x.Left.Text = "new"
x.Left.XDecl = nil
x.List = []*cc.Expr{&cc.Expr{Op: ExprType, Type: typ}}
x.XType = &cc.Type{Kind: cc.Ptr, Base: typ}
if typ.String() == "Prog" {
isGC := strings.Contains(x.Span.Start.File, "cmd/gc")
isCompiler := isGC || strings.Contains(x.Span.Start.File, "cmd/6g") || strings.Contains(x.Span.Start.File, "cmd/8g") || strings.Contains(x.Span.Start.File, "cmd/5g") || strings.Contains(x.Span.Start.File, "cmd/9g")
if isCompiler {
x.List = nil
x.Left.Text = "Ctxt.NewProg"
if !isGC {
x.Left.Text = "gc." + x.Left.Text
}
}
}
} else {
x.Left.Text = "make"
x.Left.XDecl = nil
x.XType = &cc.Type{Kind: Slice, Base: typ}
x.List = []*cc.Expr{
&cc.Expr{Op: ExprType, Type: x.XType},
count,
}
}
return true
case "strdup", "estrdup":
if len(x.List) != 1 {
fprintf(x.Span, "unsupported %v - too many args", x)
return false
}
fixGoTypesExpr(fn, x.List[0], stringType)
fixMerge(x, x.List[0])
x.XType = stringType
return true
case "strcpy", "strcat", "fmtstrcpy":
if len(x.List) != 2 {
fprintf(x.Span, "unsupported %v - too many args", x)
return false
}
fixGoTypesExpr(fn, x.List[0], nil)
fixGoTypesExpr(fn, x.List[1], stringType)
x.Op = cc.Eq
if x.Left.Text == "strcat" || x.Left.Text == "fmtstrcpy" {
x.Op = cc.AddEq
}
x.Left = x.List[0]
x.Right = x.List[1]
x.XType = stringType
return true
case "strlen":
x.Left.Text = "len"
x.Left.XDecl = nil
x.XType = intType
return true
case "strcmp":
if len(x.List) != 2 {
fprintf(x.Span, "unsupported %v - too many args", x)
return false
}
fixGoTypesExpr(fn, x.List[0], stringType)
fixGoTypesExpr(fn, x.List[1], stringType)
x.Left.Text = "stringsCompare"
x.Left.XDecl = nil
x.XType = intType
return true
case "abort":
x.Left.Text = "panic"
x.Left.XDecl = nil
x.List = []*cc.Expr{{Op: cc.Name, Text: `"abort"`}}
return true
case "TUP", "CASE":
if len(x.List) != 2 {
fprintf(x.Span, "unsupported %v - too many args", x)
return false
}
left := fixGoTypesExpr(fn, x.List[0], targ)
right := fixGoTypesExpr(fn, x.List[1], targ)
forceConvert(fn, x.List[0], left, uint32Type)
forceConvert(fn, x.List[1], right, uint32Type)
x.Op = cc.Or
x.Left = &cc.Expr{Op: cc.Lsh, Left: x.List[0], Right: &cc.Expr{Op: cc.Number, Text: "16"}, XType: left}
x.Right = x.List[1]
x.List = nil
x.XType = uint32Type
return true
case "R":
if len(x.List) != 2 {
fprintf(x.Span, "unsupported %v - too many args", x)
return false
}
left := fixGoTypesExpr(fn, x.List[0], targ)
right := fixGoTypesExpr(fn, x.List[1], targ)
forceConvert(fn, x.List[0], left, uint32Type)
forceConvert(fn, x.List[1], right, uint32Type)
x.Op = cc.Or
x.Left = x.List[0]
x.Right = &cc.Expr{Op: cc.Lsh, Left: x.List[1], Right: &cc.Expr{Op: cc.Number, Text: "24"}, XType: left}
x.List = nil
x.XType = uint32Type
return true
case "FCASE":
if len(x.List) != 3 {
fprintf(x.Span, "unsupported %v - too many args", x)
return false
}
arg0 := fixGoTypesExpr(fn, x.List[0], targ)
arg1 := fixGoTypesExpr(fn, x.List[1], targ)
arg2 := fixGoTypesExpr(fn, x.List[2], targ)
forceConvert(fn, x.List[0], arg0, uint32Type)
forceConvert(fn, x.List[1], arg1, uint32Type)
forceConvert(fn, x.List[2], arg2, uint32Type)
x.Op = cc.Or
x.Left = &cc.Expr{Op: cc.Lsh, Left: x.List[0], Right: &cc.Expr{Op: cc.Number, Text: "16"}, XType: uint32Type}
x.Right = &cc.Expr{
Op: cc.Or,
Left: &cc.Expr{Op: cc.Lsh, Left: x.List[1], Right: &cc.Expr{Op: cc.Number, Text: "8"}, XType: uint32Type},
Right: x.List[2],
}
x.List = nil
x.XType = uint32Type
return true
}
return false
}
func forceConvert(fn *cc.Decl, x *cc.Expr, actual, targ *cc.Type) {
if isEmptyInterface(targ) {
return
}
if isEmptyInterface(actual) {
old := copyExpr(x)
x.Op = TypeAssert
x.Left = old
x.Right = nil
x.List = nil
x.Type = targ
x.XType = targ
return
}
if isNumericConst(x) && targ != nil {
switch targ.Kind {
case cc.Ptr, Slice:
if x.Op == cc.Number && x.Text == "0" {
x.Op = cc.Name
x.Text = "nil"
x.XType = targ
}
case String:
if x.Op == cc.Number && x.Text == "0" {
x.Op = cc.Name
x.Text = `""`
x.XType = targ
}
}
return
}
if x.Op == cc.Name && x.Text == "nil" && targ != nil {
switch targ.Kind {
case cc.Func, cc.Ptr, Slice:
return
case String:
x.Text = `""`
x.XType = targ
x.XDecl = nil
return
}
}
if actual == nil || targ == nil {
return
}
if actual.Kind == Ideal && Int8 <= targ.Kind && targ.Kind <= Float64 {
return
}
if x != nil && x.Op == cc.Name && x.Text == "nil" {
if targ.Kind == cc.Func || targ.Kind == cc.Ptr || targ.Kind == Slice {
return
}
}
// Func conversions are never useful.
// If the func types are different, the conversion will fail;
// if not, the conversion is unnecessary.
// Either way the conversion is an eyesore.
if targ.Kind == cc.Func || targ.Kind == cc.Ptr && targ.Base.Kind == cc.Func {
return
}
if actual.Kind == Bool && Int8 <= targ.Kind && targ.Kind <= Float64 {
old := copyExpr(x)
if targ.Kind == Int {
x.Op = cc.Call
x.Left = &cc.Expr{Op: cc.Name, Text: "bool2int"}
x.List = []*cc.Expr{old}
x.Right = nil
} else {
x.Op = cc.Cast
x.Left = &cc.Expr{Op: cc.Call, Left: &cc.Expr{Op: cc.Name, Text: "bool2int"}, List: []*cc.Expr{old}}
x.Type = targ
}
return
}
if actual.Kind == cc.Array && targ.Kind == Slice && sameType(actual.Base, targ.Base) {
old := copyExpr(x)
x.Op = ExprSlice
x.List = []*cc.Expr{old, nil, nil}
x.Left = nil
x.Right = nil
return
}
if actual.Kind == Slice && targ.Kind == cc.Ptr && sameType(actual.Base, targ.Base) {
if isCall(x, "make") {
return
}
old := copyExpr(x)
x.Op = cc.Addr
x.Left = &cc.Expr{Op: cc.Index, Left: old, Right: &cc.Expr{Op: cc.Number, Text: "0"}}
return
}
if !sameType(actual, targ) {
if x.Op == cc.Twid {
forceConvert(fn, x.Left, actual, targ)
x.XType = targ
return
}
old := copyExpr(x)
// for debugging:
// old = &cc.Expr{Op: cc.Cast, Left: old, Type: actual, XType: actual}
x.Op = cc.Cast
x.Left = old
x.Right = nil
x.List = nil
x.Type = targ
x.XType = targ
if actual.Kind == cc.Array && targ.Kind == Slice {
x.Op = ExprSlice
x.List = []*cc.Expr{old, nil, nil}
x.Left = nil
x.Type = nil
}
}
}
func fixGoTypesExpr(fn *cc.Decl, x *cc.Expr, targ *cc.Type) (ret *cc.Type) {
if x == nil {
return nil
}
defer func() {
x.XType = ret
}()
if x.Op == cc.Paren {
return fixGoTypesExpr(fn, x.Left, targ)
}
// Make explicit C's implicit conversions from boolean to non-boolean and vice versa.
switch x.Op {
case cc.AndAnd, cc.OrOr, cc.Not, cc.EqEq, cc.Lt, cc.LtEq, cc.Gt, cc.GtEq, cc.NotEq:
if targ != nil && targ.Kind != Bool {
old := copyExpr(x)
if targ.Kind == Int {
x.Op = cc.Call
x.Left = &cc.Expr{Op: cc.Name, Text: "bool2int"}
x.List = []*cc.Expr{old}
x.Right = nil
} else {
x.Op = cc.Cast
x.Left = &cc.Expr{Op: cc.Call, Left: &cc.Expr{Op: cc.Name, Text: "bool2int"}, List: []*cc.Expr{old}}
x.Type = targ
}
fixGoTypesExpr(fn, old, boolType)
return targ
}
default:
if targ != nil && targ.Kind == Bool {
old := copyExpr(x)
left := fixGoTypesExpr(fn, old, nil)
if left != nil && left.Kind == Bool {
return targ
}
if old.Op == cc.Number {
switch old.Text {
case "1":
x.Op = cc.Name
x.Text = "true"
return targ
case "0":
x.Op = cc.Name
x.Text = "false"
return targ
}
}
x.Op = cc.NotEq
x.Left = old
x.Right = zeroFor(left)
fixSpecialCompare(fn, x)
return targ
}
}
fixArray(fn, x)
switch x.Op {
default:
panic(fmt.Sprintf("unexpected construct %v in fixGoTypesExpr - %v - %v", GoString(x), x.Op, x.Span))
case ExprType:
// inserted by a rewrite
return nil
case ExprSlice:
// inserted by rewriteLen
left := fixGoTypesExpr(fn, x.List[0], targ)
fixGoTypesExpr(fn, x.List[1], nil)
fixGoTypesExpr(fn, x.List[2], nil)
return left
case cc.Comma:
for i, y := range x.List {
t := targ
if i+1 < len(x.List) {
t = nil
}
fixGoTypesExpr(fn, y, t)
}
return nil
case ExprBlock:
for _, stmt := range x.Block {
fixGoTypesStmt(nil, fn, stmt)
}
return nil
case cc.Add, cc.And, cc.Div, cc.Mod, cc.Mul, cc.Or, cc.Sub, cc.Xor:
if x.Op == cc.Sub && isPtrSliceOrArray(x.Left.XType) && isPtrSliceOrArray(x.Right.XType) {
left := fixGoTypesExpr(fn, x.Left, nil)
right := fixGoTypesExpr(fn, x.Right, nil)
if left != nil && right != nil && left.Kind != right.Kind {
if left.Kind == Slice {
forceConvert(fn, x.Right, right, left)
} else {
forceConvert(fn, x.Left, left, right)
}
}
x.Left = &cc.Expr{Op: cc.Minus, Left: &cc.Expr{Op: cc.Call, Left: &cc.Expr{Op: cc.Name, Text: "cap"}, List: []*cc.Expr{x.Left}}}
x.Right = &cc.Expr{Op: cc.Call, Left: &cc.Expr{Op: cc.Name, Text: "cap"}, List: []*cc.Expr{x.Right}}
x.Op = cc.Add
return intType
}
left := fixGoTypesExpr(fn, x.Left, targ)
if x.Op == cc.And && x.Right.Op == cc.Twid {
x.Op = AndNot
x.Right = x.Right.Left
}
if x.Op == cc.Add && isSliceStringOrArray(left) {
fixGoTypesExpr(fn, x.Right, nil)
x.Op = ExprSlice
x.List = []*cc.Expr{x.Left, x.Right, nil}
x.Left = nil
x.Right = nil
if left.Kind == cc.Array {
left = &cc.Type{Kind: Slice, Base: left.Base}
}
return left
}
right := fixGoTypesExpr(fn, x.Right, targ)
return fixBinary(fn, x, left, right, targ)
case cc.AddEq, cc.AndEq, cc.DivEq, cc.Eq, cc.ModEq, cc.MulEq, cc.OrEq, cc.SubEq, cc.XorEq:
left := fixGoTypesExpr(fn, x.Left, nil)
if x.Op == cc.AndEq && x.Right.Op == cc.Twid {
x.Op = AndNotEq
x.Right = x.Right.Left
}
if x.Op == cc.AddEq && isSliceOrString(left) {
fixGoTypesExpr(fn, x.Right, nil)
old := copyExpr(x.Left)
x.Op = cc.Eq
x.Right = &cc.Expr{Op: ExprSlice, List: []*cc.Expr{old, x.Right, nil}}
return left
}
if x.Op == cc.Eq && x.Left.Op == cc.Index && sameType(x.Left.Left.XType, stringType) && GoString(x.Left.Right) == "0" && GoString(x.Right) == "0" {
x.Left = x.Left.Left
x.Right = &cc.Expr{Op: cc.Name, Text: `""`}
return x.Left.XType
}
forceGoType(fn, x.Right, left)
if x.Op == cc.Eq && x.Left != nil && x.Right != nil && x.Right.XType != nil && isCall(x.Right, "make") && x.Left.XDecl != nil && x.Left.XDecl.Type != nil && x.Left.XDecl.Type.Kind == cc.Ptr && sameType(x.Left.XDecl.Type.Base, x.Right.XType.Base) {
x.Left.XDecl.Type = x.Right.XType
x.Left.XType = x.Right.XType
left = x.Right.XType
}
return left
case ColonEq:
left := fixGoTypesExpr(fn, x.Right, nil)
x.Left.XType = left
x.Left.XDecl.Type = left
return left
case cc.Addr:
left := fixGoTypesExpr(fn, x.Left, nil)
if left == nil {
return nil
}
if targ != nil && targ.Kind == Slice && sameType(targ.Base, left) {
l := x.Left
l.Op = ExprSlice
l.List = []*cc.Expr{l.Left, l.Right, nil}
l.Left = nil
l.Right = nil
fixMerge(x, l)
return targ
}
return &cc.Type{Kind: cc.Ptr, Base: left}
case cc.AndAnd, cc.OrOr, cc.Not:
fixGoTypesExpr(fn, x.Left, boolType)
if x.Right != nil {
fixGoTypesExpr(fn, x.Right, boolType)
}
return boolType
case cc.Arrow, cc.Dot:
left := fixGoTypesExpr(fn, x.Left, nil)
if x.Op == cc.Arrow && isSliceOrString(left) {
x.Left = &cc.Expr{Op: cc.Index, Left: x.Left, Right: &cc.Expr{Op: cc.Number, Text: "0"}}
}
return x.XDecl.Type
case cc.Call:
if fixPrintf(fn, x) {
return x.XType
}
if fixSpecialCall(fn, x, targ) {
return x.XType
}
left := fixGoTypesExpr(fn, x.Left, nil)
if left != nil && left.Kind == cc.Ptr && left.Base.Kind == cc.Func {
left = left.Base
}
for i, y := range x.List {
if left != nil && left.Kind == cc.Func && i < len(left.Decls) {
forceGoType(fn, y, left.Decls[i].Type)
} else {
fixGoTypesExpr(fn, y, nil)
}
}
if left != nil && left.Kind == cc.Func {
return left.Base
}
return nil
case cc.Cast:
fixGoTypesExpr(fn, x.Left, nil)
if isEmptyInterface(x.Left.XType) {
x.Op = TypeAssert
}
return x.Type
case cc.CastInit:
fixGoTypesInit(nil, x.Init)
return x.Type
case cc.EqEq, cc.Gt, cc.GtEq, cc.Lt, cc.LtEq, cc.NotEq:
if fixSpecialCompare(fn, x) {
return boolType
}
left := fixGoTypesExpr(fn, x.Left, nil)
if x.Right.Op == cc.Number && x.Right.Text == "0" || x.Right.Op == cc.Name && x.Right.Text == "nil" {
if isSliceOrPtr(left) {
x.Right.Op = cc.Name
x.Right.Text = "nil"
return boolType
}
if left != nil && left.Kind == String {
x.Right.Op = cc.String
x.Right.Texts = []string{`""`}
return boolType
}
}
right := fixGoTypesExpr(fn, x.Right, nil)
if isSliceOrArray(x.Left.XType) && isSliceOrArray(x.Right.XType) {
x.Left = &cc.Expr{Op: cc.Minus, Left: &cc.Expr{Op: cc.Call, Left: &cc.Expr{Op: cc.Name, Text: "cap"}, List: []*cc.Expr{x.Left}}}
x.Right = &cc.Expr{Op: cc.Minus, Left: &cc.Expr{Op: cc.Call, Left: &cc.Expr{Op: cc.Name, Text: "cap"}, List: []*cc.Expr{x.Right}}}
return boolType
}
fixBinary(fn, x, left, right, nil)
return boolType
case cc.Index, cc.Indir:
left := fixGoTypesExpr(fn, x.Left, nil)
if x.Right != nil {
fixGoTypesExpr(fn, x.Right, nil)
}
if left == nil {
return nil
}
if isSliceOrString(left) && x.Op == cc.Indir {
x.Op = cc.Index
x.Right = &cc.Expr{Op: cc.Number, Text: "0"}
}
switch left.Kind {
case cc.Ptr, Slice, cc.Array:
if x.Op == cc.Indir && left.Kind == cc.Ptr && left.Base.Kind == cc.Func {
*x = *x.Left
}
return left.Base
case String:
return byteType
}
return nil
case cc.Lsh, cc.Rsh:
left := fixGoTypesExpr(fn, x.Left, targ)
if left != nil && targ != nil && Int8 <= left.Kind && left.Kind <= Float64 && targ.Kind > left.Kind {
forceConvert(fn, x.Left, left, targ)
left = targ
}
fixShiftCount(fn, x.Right)
return left
case cc.LshEq, cc.RshEq:
left := fixGoTypesExpr(fn, x.Left, nil)
fixShiftCount(fn, x.Right)
return left
case cc.Name:
if x.Text == "nelem" {
}
switch x.Text {
case "T", "S", "N", "L", "P", "C":
x.Text = "nil"
x.XDecl = nil
return nil
case "nelem":
x.Text = "len"
x.XDecl = nil
fallthrough
case "len":
return &cc.Type{Kind: cc.Func, Base: intType}
}
if x.XDecl == nil {
if x.Text == "true" || x.Text == "false" {
return x.XType
}
return nil
}
return x.XDecl.Type
case cc.Number:
return idealType
case cc.Minus, cc.Plus, cc.Twid:
return fixGoTypesExpr(fn, x.Left, targ)
case cc.Offsetof:
// TODO
return nil
case cc.Paren:
return fixGoTypesExpr(fn, x.Left, targ)
case cc.PostDec, cc.PostInc:
left := fixGoTypesExpr(fn, x.Left, nil)
if x.Op == cc.PostInc && isSliceOrString(left) {
old := copyExpr(x.Left)
x.Op = cc.Eq
x.Right = &cc.Expr{Op: ExprSlice, List: []*cc.Expr{old, &cc.Expr{Op: cc.Number, Text: "1"}, nil}}
}
return nil
case cc.SizeofExpr:
left := fixGoTypesExpr(fn, x.Left, nil)
if left != nil && (left.Kind == cc.Array || left.Kind == Slice) && left.Base.Def().Is(Uint8) {
x.Op = cc.Call
x.List = []*cc.Expr{x.Left}
x.Left = &cc.Expr{Op: cc.Name, Text: "len"}
return intType
}
return nil
case cc.SizeofType:
return nil
case cc.String:
return &cc.Type{Kind: String}
case cc.VaArg:
// TODO
return nil
}
}
func negate(x *cc.Expr) *cc.Expr {
switch x.Op {
case cc.Paren:
return negate(x.Left)
case cc.OrOr:
x.Op = cc.AndAnd
x.Left = negate(x.Left)
x.Right = negate(x.Right)
case cc.AndAnd:
x.Op = cc.OrOr
x.Left = negate(x.Left)
x.Right = negate(x.Right)
case cc.EqEq:
x.Op = cc.NotEq
case cc.NotEq:
x.Op = cc.EqEq
case cc.Lt:
x.Op = cc.GtEq
case cc.GtEq:
x.Op = cc.Lt
case cc.Gt:
x.Op = cc.LtEq
case cc.LtEq:
x.Op = cc.Gt
default:
x = &cc.Expr{Op: cc.Not, Left: x}
}
return x
}
func fixSpecialCompare(fn *cc.Decl, x *cc.Expr) bool {
if (x.Right.Op != cc.Number || x.Right.Text != "0") && x.Right.String() != "nil" && x.Right.String() != `""` || x.Left.Op != cc.Call || x.Left.Left.Op != cc.Name {
return false
}
call := x.Left
switch call.Left.Text {
case "memcmp":
if len(call.List) != 3 {
// fprintf(x.Span, "unsupported %v", x)
return false
}
obj1, obj1Type := objIndir(fn, call.List[0])
obj2, obj2Type := objIndir(fn, call.List[1])
if obj1Type == nil || !sameType(obj1Type, obj2Type) {
// fprintf(x.Span, "unsupported %v", call)
return true
}
if !matchSize(fn, obj1, obj1Type, call.List[2]) && !matchSize(fn, obj2, obj2Type, call.List[2]) {
// fprintf(x.Span, "unsupported %v - wrong size", call)
return true
}
x.Left = obj1
x.Right = obj2
x.List = nil
x.XType = boolType
return true
case "strncmp":
if len(call.List) != 3 {
fprintf(x.Span, "unsupported %v", x)
return false
}
call.Left = &cc.Expr{Op: cc.Name, Text: "strings.HasPrefix"}
call.List = call.List[:2]
call.XType = boolType
if x.Op == cc.EqEq {
*x = *call
} else if x.Op == cc.NotEq {
x.Op = cc.Not
x.Right = nil
}
x.XType = boolType
return true
case "strstr":
if len(call.List) != 2 {
fprintf(x.Span, "unsupported %v", x)
return false
}
call.Left = &cc.Expr{Op: cc.Name, Text: "strings.Contains"}
call.XType = boolType
if x.Op == cc.NotEq {
*x = *call
} else if x.Op == cc.EqEq {
x.Op = cc.Not
x.Right = nil
}
x.XType = boolType
return true
case "utfrune":
if len(call.List) != 2 {
fprintf(x.Span, "unsupported %v", x)
return false
}
call.Left = &cc.Expr{Op: cc.Name, Text: "strings.ContainsRune"}
call.XType = boolType
if x.Op == cc.NotEq {
*x = *call
} else if x.Op == cc.EqEq {
x.Op = cc.Not
x.Right = nil
}
x.XType = boolType
return true
case "ucistrcmp":
if len(call.List) != 2 {
fprintf(x.Span, "unsupported %v", x)
return false
}
call.Left = &cc.Expr{Op: cc.Name, Text: "strings.EqualFold"}
call.XType = boolType
if x.Op == cc.EqEq {
*x = *call
} else if x.Op == cc.NotEq {
x.Op = cc.Not
x.Right = nil
}
x.XType = boolType
return true
case "strcmp":
if len(call.List) != 2 {
fprintf(x.Span, "unsupported %v", x)
return false
}
obj1 := call.List[0]
obj2 := call.List[1]
x.Left = obj1
x.Right = obj2
x.List = nil
x.XType = boolType
return true
case "isspacerune":
if len(call.List) != 1 {
fprintf(x.Span, "unsupported %v", x)
return false
}
call.Left.Text = "unicode.IsSpace"
call.Left.XDecl = nil
forceConvert(fn, call.List[0], call.List[0].XType, runeType)
if x.Op == cc.NotEq {
*x = *call
} else if x.Op == cc.EqEq {
x.Op = cc.Not
x.Right = nil
}
x.XType = boolType
return true
}
return false
}
func doSideEffects(x *cc.Expr, before, after *[]*cc.Stmt, mode int) {
if x == nil {
return
}
// Cannot hoist side effects from conditionally evaluated expressions
// into unconditionally evaluated statement lists.
// For now, detect but do not handle.
switch x.Op {
case cc.Cond:
doSideEffects(x.List[0], before, after, mode&^sideStmt|sideNoAfter)
checkNoSideEffects(x.List[1], 0)
checkNoSideEffects(x.List[2], 0)
case cc.AndAnd, cc.OrOr:
doSideEffects(x.Left, before, after, mode&^sideStmt|sideNoAfter)
checkNoSideEffects(x.Right, 0)
case cc.Comma:
var leftover []*cc.Expr
for i, y := range x.List {
m := mode | sideNoAfter
if i+1 < len(x.List) {
m |= sideStmt
}
doSideEffects(y, before, after, m)
switch y.Op {
case cc.PostInc, cc.PostDec, cc.Eq, cc.AddEq, cc.SubEq, cc.MulEq, cc.DivEq, cc.ModEq, cc.XorEq, cc.OrEq, cc.AndEq, cc.LshEq, cc.RshEq:
*before = append(*before, &cc.Stmt{Op: cc.StmtExpr, Expr: y})
default:
leftover = append(leftover, y)
}
}
x.List = leftover
default:
doSideEffects(x.Left, before, after, mode&^sideStmt)
doSideEffects(x.Right, before, after, mode&^sideStmt)
for _, y := range x.List {
doSideEffects(y, before, after, mode&^sideStmt)
}
}
if mode&sideStmt != 0 {
// Expression as statement.
// Can leave x++ alone, can rewrite ++x to x++, can leave x [op]= y alone.
switch x.Op {
case cc.PreInc:
x.Op = cc.PostInc
return
case cc.PreDec:
x.Op = cc.PostDec
return
case cc.PostInc, cc.PostDec:
return
case cc.Eq, cc.AddEq, cc.SubEq, cc.MulEq, cc.DivEq, cc.ModEq, cc.XorEq, cc.OrEq, cc.AndEq, cc.LshEq, cc.RshEq:
return
case cc.Call:
return
}
}
switch x.Op {
case cc.Eq, cc.AddEq, cc.SubEq, cc.MulEq, cc.DivEq, cc.ModEq, cc.XorEq, cc.OrEq, cc.AndEq, cc.LshEq, cc.RshEq:
x.Left = forceCheap(before, x.Left)
old := copyExpr(x)
*before = append(*before, &cc.Stmt{Op: cc.StmtExpr, Expr: old})
fixMerge(x, x.Left)
case cc.PreInc, cc.PreDec:
x.Left = forceCheap(before, x.Left)
old := copyExpr(x)
old.SyntaxInfo = cc.SyntaxInfo{}
if old.Op == cc.PreInc {
old.Op = cc.PostInc
} else {
old.Op = cc.PostDec
}
*before = append(*before, &cc.Stmt{Op: cc.StmtExpr, Expr: old})
fixMerge(x, x.Left)
case cc.PostInc, cc.PostDec:
x.Left = forceCheap(before, x.Left)
if mode&sideNoAfter != 0 {
// Not allowed to generate fixups afterward.
d := &cc.Decl{
Name: fmt.Sprintf("tmp%d", <-tmpGen),
Type: x.Left.XType,
}
eq := &cc.Expr{
Op: ColonEq,
Left: &cc.Expr{Op: cc.Name, Text: d.Name, XDecl: d},
Right: x.Left,
}
old := copyExpr(x.Left)
old.SyntaxInfo = cc.SyntaxInfo{}
*before = append(*before,
&cc.Stmt{Op: cc.StmtExpr, Expr: eq},
&cc.Stmt{Op: cc.StmtExpr, Expr: &cc.Expr{Op: x.Op, Left: old}},
)
x.Op = cc.Name
x.Text = d.Name
x.XDecl = d
x.Left = nil
break
}
old := copyExpr(x)
old.SyntaxInfo = cc.SyntaxInfo{}
*after = append(*after, &cc.Stmt{Op: cc.StmtExpr, Expr: old})
fixMerge(x, x.Left)
case cc.Cond:
// Rewrite c ? y : z into tmp with initialization:
// var tmp typeof(c?y:z)
// if c {
// tmp = y
// } else {
// tmp = z
// }
d := &cc.Decl{
Name: "tmp",
Type: x.XType,
}
*before = append(*before,
&cc.Stmt{Op: cc.StmtDecl, Decl: d},
&cc.Stmt{Op: cc.If, Expr: x.List[0],
Body: &cc.Stmt{
Op: cc.StmtExpr,
Expr: &cc.Expr{
Op: cc.Eq,
Left: &cc.Expr{Op: cc.Name, Text: d.Name, XDecl: d},
Right: x.List[1],
},
},
Else: &cc.Stmt{
Op: cc.StmtExpr,
Expr: &cc.Expr{
Op: cc.Eq,
Left: &cc.Expr{Op: cc.Name, Text: d.Name, XDecl: d},
Right: x.List[2],
},
},
},
)
x.Op = cc.Name
x.Text = d.Name
x.XDecl = d
x.List = nil
case cc.Call:
if x.Left.Text == "fmtstrcpy" || x.Left.Text == "fmtprint" {
old := copyExpr(x)
old.SyntaxInfo = cc.SyntaxInfo{}
*before = append(*before, &cc.Stmt{Op: cc.StmtExpr, Expr: old})
x.Op = cc.Number
x.Text = "0"
x.XDecl = nil
x.Left = nil
x.List = nil
}
}
}
// fixArrays rewrites uses of the untyped "Array" container defined in cmd/gc
// to use native Go slices.
// It has nothing to do with standard C arrays.
func fixArray(fn *cc.Decl, x *cc.Expr) {
// arraynew(n, sizeof(T)) becomes Go make([]T, 0, n).
if isCall(x, "arraynew") {
if len(x.List) != 2 {
fprintf(x.Span, "wrong number of arguments to arraynew")
return
}
if x.List[1].Op != cc.SizeofType {
fprintf(x.Span, "second argument to arraynew must be sizeof(T)")
return
}
x.Left.Text = "make"
x.Left.XDecl = nil
typ := &cc.Type{Kind: Slice, Base: x.List[1].Type}
x.XType = typ
x.List = append(x.List, x.List[0])
x.List[1] = &cc.Expr{Op: cc.Number, Text: "0"}
x.List[0] = &cc.Expr{Op: ExprType, Type: typ}
return
}
// arraylength(x) becomes len(x)
if isCall(x, "arraylength") {
x.Left.Text = "len"
x.Left.XDecl = nil
return
}
// arrayset is unused in practice!
// arrayadd(x, &elem) becomes x = append(x, elem).
// Strictly speaking, this is not a complete translation,
// because in the C code x might be a pointer taken from
// another place, and arrayadd changes the len at that
// other place too. In cmd/gc this does not happen.
if isCall(x, "arrayadd") {
if len(x.List) != 2 {
fprintf(x.Span, "wrong number of arguments to arrayadd")
return
}
if x.List[1].Op != cc.Addr {
fprintf(x.Span, "second argument to arrayadd must be &x, have %v", x.List[1])
return
}
append := copyExpr(x)
append.Left.Text = "append"
append.Left.XDecl = nil
x.Op = cc.Eq
x.Left = append.List[0]
x.Right = append
append.List[1] = append.List[1].Left
return
}
// *(T**)(arrayget(x, i)) turns into x[i].
// Record that x should have translated type T*.
if x.Op == cc.Indir && x.Left.Op == cc.Cast && x.Left.Type.Kind == cc.Ptr && x.Left.Type.Base.Kind == cc.Ptr && isCall(x.Left.Left, "arrayget") {
call := x.Left.Left
x.Op = cc.Index
x.XType = x.Left.Type.Base
x.Left = call.List[0]
x.Right = call.List[1]
saveSliceType(x.Left, x.XType)
return
}
// TODO: arraysort
}