[dev.regabi] cmd/compile: split SliceHeaderExpr.LenCap into separate fields

Passes toolstash -cmp.

Change-Id: Ifc98a408c154a05997963e2c731466842ebbf50e
Reviewed-on: https://go-review.googlesource.com/c/go/+/279958
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>

src/cmd/compile/internal/ir/expr.go

@@ -696,15 +696,15 @@ func (o Op) IsSlice3() bool {
 type SliceHeaderExpr struct {
 	miniExpr
 	Ptr Node
-	LenCap Nodes // TODO(rsc): Split into two Node fields
+	Len Node
+	Cap Node
 }
 
 func NewSliceHeaderExpr(pos src.XPos, typ *types.Type, ptr, len, cap Node) *SliceHeaderExpr {
-	n := &SliceHeaderExpr{Ptr: ptr}
+	n := &SliceHeaderExpr{Ptr: ptr, Len: len, Cap: cap}
 	n.pos = pos
 	n.op = OSLICEHEADER
 	n.typ = typ
-	n.LenCap = []Node{len, cap}
 	return n
 }
 

src/cmd/compile/internal/ir/fmt.go

@@ -800,10 +800,7 @@ func exprFmt(n Node, s fmt.State, prec int) {
 
 	case OSLICEHEADER:
 		n := n.(*SliceHeaderExpr)
-		if len(n.LenCap) != 2 {
+		fmt.Fprintf(s, "sliceheader{%v,%v,%v}", n.Ptr, n.Len, n.Cap)
-			base.Fatalf("bad OSLICEHEADER list length %d", len(n.LenCap))
-		}
-		fmt.Fprintf(s, "sliceheader{%v,%v,%v}", n.Ptr, n.LenCap[0], n.LenCap[1])
 
 	case OCOMPLEX, OCOPY:
 		n := n.(*BinaryExpr)

src/cmd/compile/internal/ir/node_gen.go

@@ -858,20 +858,21 @@ func (n *SliceHeaderExpr) Format(s fmt.State, verb rune) { FmtNode(n, s, verb) }
 func (n *SliceHeaderExpr) copy() Node {
 	c := *n
 	c.init = c.init.Copy()
-	c.LenCap = c.LenCap.Copy()
 	return &c
 }
 func (n *SliceHeaderExpr) doChildren(do func(Node) error) error {
 	var err error
 	err = maybeDoList(n.init, err, do)
 	err = maybeDo(n.Ptr, err, do)
-	err = maybeDoList(n.LenCap, err, do)
+	err = maybeDo(n.Len, err, do)
+	err = maybeDo(n.Cap, err, do)
 	return err
 }
 func (n *SliceHeaderExpr) editChildren(edit func(Node) Node) {
 	editList(n.init, edit)
 	n.Ptr = maybeEdit(n.Ptr, edit)
-	editList(n.LenCap, edit)
+	n.Len = maybeEdit(n.Len, edit)
+	n.Cap = maybeEdit(n.Cap, edit)
 }
 
 func (n *SliceType) Format(s fmt.State, verb rune) { FmtNode(n, s, verb) }

src/cmd/compile/internal/ssagen/ssa.go

@@ -2844,8 +2844,8 @@ func (s *state) expr(n ir.Node) *ssa.Value {
 	case ir.OSLICEHEADER:
 		n := n.(*ir.SliceHeaderExpr)
 		p := s.expr(n.Ptr)
-		l := s.expr(n.LenCap[0])
+		l := s.expr(n.Len)
-		c := s.expr(n.LenCap[1])
+		c := s.expr(n.Cap)
 		return s.newValue3(ssa.OpSliceMake, n.Type(), p, l, c)
 
 	case ir.OSLICE, ir.OSLICEARR, ir.OSLICE3, ir.OSLICE3ARR:

src/cmd/compile/internal/typecheck/expr.go

@@ -924,30 +924,22 @@ func tcSliceHeader(n *ir.SliceHeaderExpr) ir.Node {
 		base.Fatalf("need unsafe.Pointer for OSLICEHEADER")
 	}
 
-	if x := len(n.LenCap); x != 2 {
-		base.Fatalf("expected 2 params (len, cap) for OSLICEHEADER, got %d", x)
-	}
-
 	n.Ptr = Expr(n.Ptr)
-	l := Expr(n.LenCap[0])
+	n.Len = DefaultLit(Expr(n.Len), types.Types[types.TINT])
-	c := Expr(n.LenCap[1])
+	n.Cap = DefaultLit(Expr(n.Cap), types.Types[types.TINT])
-	l = DefaultLit(l, types.Types[types.TINT])
-	c = DefaultLit(c, types.Types[types.TINT])
 
-	if ir.IsConst(l, constant.Int) && ir.Int64Val(l) < 0 {
+	if ir.IsConst(n.Len, constant.Int) && ir.Int64Val(n.Len) < 0 {
 		base.Fatalf("len for OSLICEHEADER must be non-negative")
 	}
 
-	if ir.IsConst(c, constant.Int) && ir.Int64Val(c) < 0 {
+	if ir.IsConst(n.Cap, constant.Int) && ir.Int64Val(n.Cap) < 0 {
 		base.Fatalf("cap for OSLICEHEADER must be non-negative")
 	}
 
-	if ir.IsConst(l, constant.Int) && ir.IsConst(c, constant.Int) && constant.Compare(l.Val(), token.GTR, c.Val()) {
+	if ir.IsConst(n.Len, constant.Int) && ir.IsConst(n.Cap, constant.Int) && constant.Compare(n.Len.Val(), token.GTR, n.Cap.Val()) {
 		base.Fatalf("len larger than cap for OSLICEHEADER")
 	}
 
-	n.LenCap[0] = l
-	n.LenCap[1] = c
 	return n
 }
 

src/cmd/compile/internal/walk/builtin.go

@@ -438,7 +438,8 @@ func walkMakeSlice(n *ir.MakeExpr, init *ir.Nodes) ir.Node {
 	fn := typecheck.LookupRuntime(fnname)
 	m.Ptr = mkcall1(fn, types.Types[types.TUNSAFEPTR], init, reflectdata.TypePtr(t.Elem()), typecheck.Conv(len, argtype), typecheck.Conv(cap, argtype))
 	m.Ptr.MarkNonNil()
-	m.LenCap = []ir.Node{typecheck.Conv(len, types.Types[types.TINT]), typecheck.Conv(cap, types.Types[types.TINT])}
+	m.Len = typecheck.Conv(len, types.Types[types.TINT])
+	m.Cap = typecheck.Conv(cap, types.Types[types.TINT])
 	return walkExpr(typecheck.Expr(m), init)
 }
 
@@ -471,7 +472,8 @@ func walkMakeSliceCopy(n *ir.MakeExpr, init *ir.Nodes) ir.Node {
 		sh := ir.NewSliceHeaderExpr(base.Pos, nil, nil, nil, nil)
 		sh.Ptr = mkcall1(fn, types.Types[types.TUNSAFEPTR], init, size, typecheck.NodNil(), ir.NewBool(false))
 		sh.Ptr.MarkNonNil()
-		sh.LenCap = []ir.Node{length, length}
+		sh.Len = length
+		sh.Cap = length
 		sh.SetType(t)
 
 		s := typecheck.Temp(t)
@@ -493,7 +495,8 @@ func walkMakeSliceCopy(n *ir.MakeExpr, init *ir.Nodes) ir.Node {
 	s := ir.NewSliceHeaderExpr(base.Pos, nil, nil, nil, nil)
 	s.Ptr = mkcall1(fn, types.Types[types.TUNSAFEPTR], init, reflectdata.TypePtr(t.Elem()), length, copylen, typecheck.Conv(copyptr, types.Types[types.TUNSAFEPTR]))
 	s.Ptr.MarkNonNil()
-	s.LenCap = []ir.Node{length, length}
+	s.Len = length
+	s.Cap = length
 	s.SetType(t)
 	return walkExpr(typecheck.Expr(s), init)
 }

src/cmd/compile/internal/walk/expr.go

@@ -817,8 +817,8 @@ func walkSlice(n *ir.SliceExpr, init *ir.Nodes) ir.Node {
 // walkSliceHeader walks an OSLICEHEADER node.
 func walkSliceHeader(n *ir.SliceHeaderExpr, init *ir.Nodes) ir.Node {
 	n.Ptr = walkExpr(n.Ptr, init)
-	n.LenCap[0] = walkExpr(n.LenCap[0], init)
+	n.Len = walkExpr(n.Len, init)
-	n.LenCap[1] = walkExpr(n.LenCap[1], init)
+	n.Cap = walkExpr(n.Cap, init)
 	return n
 }