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 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 && c2go.GoString(targ.Left) == c2go.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
return true
}
if tryPrintf(curfn, x, "print", 0, "fmt.Printf") {
return true
}
if tryPrintf(curfn, x, "sysfatal", 0, "log.Fatalf") {
return true
}
if tryPrintf(curfn, x, "ctxt.diag", 0, "ctxt.diag") {
return true
}
if tryPrintf(curfn, x, "Bprint", 1, "fmt.Fprintf") {
return true
}
if tryPrintf(curfn, x, "smprint", 0, "fmt.Sprintf") {
return true
}
return false
}
func fixSpecialCompare(fn *cc.Decl, x *cc.Expr) bool {
if x.Right.Op != cc.Number || x.Right.Text != "0" || 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 "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
}
return false
}
func forceConvert(fn *cc.Decl, x *cc.Expr, actual, targ *cc.Type) {
if isNumericConst(x) && targ != nil {
switch targ.Kind {
case cc.Ptr, c2go.Slice:
if x.Op == cc.Number && x.Text == "0" {
x.Op = cc.Name
x.Text = "nil"
x.XType = targ
}
case c2go.String:
if x.Op == cc.Number && x.Text == "0" {
x.Op = cc.Name
x.Text = `""`
x.XType = targ
}
}
return
}
if actual == nil || targ == nil {
return
}
if actual.Kind == c2go.Ideal && c2go.Int8 <= targ.Kind && targ.Kind <= c2go.Float64 {
return
}
if x != nil && x.Op == cc.Name && x.Text == "nil" {
if targ.Kind == cc.Func || targ.Kind == cc.Ptr || targ.Kind == c2go.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 == c2go.Bool && c2go.Int8 <= targ.Kind && targ.Kind <= c2go.Float64 {
old := copyExpr(x)
if targ.Kind == c2go.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 == c2go.Slice && sameType(actual.Base, targ.Base) {
old := copyExpr(x)
x.Op = c2go.ExprSlice
x.List = []*cc.Expr{old, nil, nil}
x.Left = nil
x.Right = nil
return
}
if actual.Kind == c2go.Slice && targ.Kind == cc.Ptr && sameType(actual.Base, targ.Base) {
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) {
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 == c2go.Slice {
x.Op = c2go.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 != c2go.Bool {
old := copyExpr(x)
if targ.Kind == c2go.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 == c2go.Bool {
old := copyExpr(x)
left := fixGoTypesExpr(fn, old, nil)
if left != nil && left.Kind == c2go.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)
return targ
}
}
switch x.Op {
default:
panic(fmt.Sprintf("unexpected construct %v in fixGoTypesExpr - %v - %v", c2go.GoString(x), x.Op, x.Span))
case c2go.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 c2go.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 == c2go.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 = c2go.AndNot
x.Right = x.Right.Left
}
if x.Op == cc.Add && isSliceStringOrArray(left) {
fixGoTypesExpr(fn, x.Right, nil)
x.Op = c2go.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: c2go.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 = c2go.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: c2go.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) && c2go.GoString(x.Left.Right) == "0" && c2go.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)
return left
case c2go.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 == c2go.Slice && sameType(targ.Base, left) {
l := x.Left
l.Op = c2go.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)
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)
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" {
if isSliceOrPtr(left) {
x.Right.Op = cc.Name
x.Right.Text = "nil"
return boolType
}
if left != nil && left.Kind == c2go.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, c2go.Slice, cc.Array:
return left.Base
case c2go.String:
return byteType
}
return nil
case cc.Lsh, cc.Rsh:
left := fixGoTypesExpr(fn, x.Left, targ)
if left != nil && targ != nil && c2go.Int8 <= left.Kind && left.Kind <= c2go.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":
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 {
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: c2go.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 == c2go.Slice) && left.Base.Def().Is(c2go.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: c2go.String}
case cc.VaArg:
// TODO
return nil
}
}
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 == c2go.Uint32 || obj1Type.Kind == c2go.Int32) && obj2Type.Kind == c2go.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, c2go.GoString(obj1Type), c2go.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 == c2go.Uint64 || obj1Type.Kind == c2go.Int64) && obj2Type.Kind == c2go.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, c2go.GoString(obj1Type), c2go.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 == c2go.Slice && c2go.GoString(x.List[1]) == c2go.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, c2go.GoString(obj2Type), c2go.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(c2go.Uint8) && right.Base.Is(c2go.Uint8) {
x.Left.Text = "copy"
x.Left.XDecl = nil
if x.List[1].Op == c2go.ExprSlice && x.List[1].List[1] == nil {
x.List[1].List[2] = siz
} else {
x.List[1] = &cc.Expr{Op: c2go.ExprSlice, List: []*cc.Expr{x.List[1], nil, siz}}
}
x.List = x.List[:2]
return true
}
fprintf(x.Span, "unsupported %v (%v %v)", x, c2go.GoString(left), c2go.GoString(right))
return true
case "mal", "malloc", "emallocz":
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
}
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: cc.Name, Text: c2go.GoString(typ)}}
x.XType = &cc.Type{Kind: cc.Ptr, Base: typ}
} else {
x.Left.Text = "make"
x.Left.XDecl = nil
x.List = []*cc.Expr{
&cc.Expr{Op: cc.Name, Text: "[]" + c2go.GoString(typ)},
count,
}
x.XType = &cc.Type{Kind: c2go.Slice, Base: typ}
}
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 "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)
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 = fixBinary(fn, x, left, right, targ)
return true
}
return false
}
func fixQsortCmp(decl *cc.Decl) *cc.Type {
ftyp := decl.Type
if ftyp.Kind != cc.Func || len(ftyp.Decls) != 2 || !isGoVoidPtr(ftyp.Decls[0].Type) || !isGoVoidPtr(ftyp.Decls[1].Type) {
fprintf(decl.Span, "invalid qsort cmp function %v - wrong args", c2go.GoString(ftyp))
return nil
}
a1, a2 := ftyp.Decls[0], ftyp.Decls[1]
var eq1, eq2, p1, p2 *cc.Expr
var indir1, indir2 bool
cc.Preorder(decl.Body, func(x cc.Syntax) {
switch x := x.(type) {
case *cc.Expr:
if x.Op != cc.Eq {
return
}
r := x.Right
if r.Op == cc.Indir {
r = r.Left
}
if r.Op == cc.Cast && r.Left.Op == cc.Name {
if r.Left.XDecl == a1 && p1 == nil {
p1 = x.Left
eq1 = x
indir1 = r != x.Right
}
if r.Left.XDecl == a2 && p2 == nil {
p2 = x.Left
eq2 = x
indir1 = r != x.Right
}
}
}
})
if p1 == nil || p2 == nil {
fprintf(decl.Span, "invalid qsort cmp function - cannot find arg extraction")
return nil
}
if !sameType(p1.XType, p2.XType) {
fprintf(decl.Span, "invalid qsort cmp function - different arg types %v and %v", c2go.GoString(p1.XType), c2go.GoString(p2.XType))
return nil
}
if indir1 != indir2 {
fprintf(decl.Span, "invalid qsort cmp function - different arg indirection")
return nil
}
typ := p1.XType
if !indir1 {
if typ.Def().Kind != cc.Ptr {
fprintf(decl.Span, "invalid qsort cmp function - arg ptr cast to non-ptr %v", c2go.GoString(typ))
return nil
}
typ = typ.Def().Base
}
// Have all the information. Committed.
// Rewrite to take x, i, j, use x[i] for p1, x[j] for p2,
// take address of x[i], x[j] if there was no indirect,
// replace all return z with return z < 0.
cmp := decl.Name
decl.Name = "(x " + cmp + ") Less"
decl.Type = &cc.Type{
Kind: cc.Func,
Base: boolType,
Decls: []*cc.Decl{
{Name: "i", Type: &cc.Type{Kind: cc.TypedefType}},
{Name: "j", Type: intType},
},
}
prefix := ""
if !indir1 {
prefix = "&"
}
eq1.Right = &cc.Expr{Op: cc.Name, Text: prefix + "x[i]", XType: p1.XType}
eq2.Right = &cc.Expr{Op: cc.Name, Text: prefix + "x[j]", XType: p1.XType}
cc.Preorder(decl.Body, func(x cc.Syntax) {
switch x := x.(type) {
case *cc.Stmt:
if x.Op == cc.Return && x.Expr != nil {
ret := x.Expr
// Pick off 0, -1, +1.
// Otherwise rewrite ret to ret < 0.
switch ret.Op {
case cc.Minus, cc.Plus:
if ret.Left.Op == cc.Number {
ret.Op = cc.Name
if ret.Op == cc.Plus {
ret.Text = "true"
} else {
ret.Text = "false"
}
ret.Left = nil
ret.XType = boolType
return
}
case cc.Number:
ret.Op = cc.Name
ret.Text = "false"
ret.XType = boolType
return
}
x.Expr = &cc.Expr{Op: cc.Lt, Left: ret, Right: &cc.Expr{Op: cc.Number, Text: "0"}, XType: boolType}
return
}
}
})
return typ
}