cmd/compile: remove Addable flag

This flag is supposed to indicate whether the expression is
"addressable"; but in practice, we infer this from other
attributes about the expression (e.g., n.Op and n.Class()).

Passes toolstash-check.

Change-Id: I19352ca07ab5646e232d98e8a7c1c9aec822ddd0
Reviewed-on: https://go-review.googlesource.com/c/go/+/200897
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

src/cmd/compile/internal/gc/dcl.go

@@ -203,7 +203,6 @@ func newnoname(s *types.Sym) *Node {
 	}
 	n := nod(ONONAME, nil, nil)
 	n.Sym = s
-	n.SetAddable(true)
 	n.Xoffset = 0
 	return n
 }
@@ -282,7 +281,6 @@ func oldname(s *types.Sym) *Node {
 			c.SetIsClosureVar(true)
 			c.SetIsDDD(n.IsDDD())
 			c.Name.Defn = n
-			c.SetAddable(false)
 
 			// Link into list of active closure variables.
 			// Popped from list in func closurebody.

src/cmd/compile/internal/gc/esc.go

@@ -283,7 +283,6 @@ func moveToHeap(n *Node) {
 		// and substitute that copy into the function declaration list
 		// so that analyses of the local (on-stack) variables use it.
 		stackcopy := newname(n.Sym)
-		stackcopy.SetAddable(false)
 		stackcopy.Type = n.Type
 		stackcopy.Xoffset = n.Xoffset
 		stackcopy.SetClass(n.Class())

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

@@ -417,10 +417,6 @@ func (n *Node) format(s fmt.State, verb rune, mode fmtMode) {
 func (n *Node) jconv(s fmt.State, flag FmtFlag) {
 	c := flag & FmtShort
 
-	if c == 0 && n.Addable() {
-		fmt.Fprintf(s, " a(%v)", n.Addable())
-	}
-
 	if c == 0 && n.Name != nil && n.Name.Vargen != 0 {
 		fmt.Fprintf(s, " g(%d)", n.Name.Vargen)
 	}

src/cmd/compile/internal/gc/reflect.go

@@ -1024,7 +1024,6 @@ func typename(t *types.Type) *Node {
 
 	n := nod(OADDR, asNode(s.Def), nil)
 	n.Type = types.NewPtr(asNode(s.Def).Type)
-	n.SetAddable(true)
 	n.SetTypecheck(1)
 	return n
 }
@@ -1045,7 +1044,6 @@ func itabname(t, itype *types.Type) *Node {
 
 	n := nod(OADDR, asNode(s.Def), nil)
 	n.Type = types.NewPtr(asNode(s.Def).Type)
-	n.SetAddable(true)
 	n.SetTypecheck(1)
 	return n
 }
@@ -1886,7 +1884,6 @@ func zeroaddr(size int64) *Node {
 	}
 	z := nod(OADDR, asNode(s.Def), nil)
 	z.Type = types.NewPtr(types.Types[TUINT8])
-	z.SetAddable(true)
 	z.SetTypecheck(1)
 	return z
 }

src/cmd/compile/internal/gc/sinit.go

@@ -388,7 +388,7 @@ func isLiteral(n *Node) bool {
 }
 
 func (n *Node) isSimpleName() bool {
-	return n.Op == ONAME && n.Addable() && n.Class() != PAUTOHEAP && n.Class() != PEXTERN
+	return n.Op == ONAME && n.Class() != PAUTOHEAP && n.Class() != PEXTERN
 }
 
 func litas(l *Node, r *Node, init *Nodes) {
@@ -1018,7 +1018,7 @@ func stataddr(nam *Node, n *Node) bool {
 	switch n.Op {
 	case ONAME:
 		*nam = *n
-		return n.Addable()
+		return true
 
 	case ODOT:
 		if !stataddr(nam, n.Left) {

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

@@ -6151,7 +6151,6 @@ func (e *ssafn) splitSlot(parent *ssa.LocalSlot, suffix string, offset int64, t
 	n.Sym = s
 	n.Type = t
 	n.SetClass(PAUTO)
-	n.SetAddable(true)
 	n.Esc = EscNever
 	n.Name.Curfn = e.curfn
 	e.curfn.Func.Dcl = append(e.curfn.Func.Dcl, n)

src/cmd/compile/internal/gc/subr.go

@@ -370,7 +370,6 @@ func newnamel(pos src.XPos, s *types.Sym) *Node {
 	n.Orig = n
 
 	n.Sym = s
-	n.SetAddable(true)
 	return n
 }
 

src/cmd/compile/internal/gc/syntax.go

@@ -153,7 +153,6 @@ const (
 	_, nodeNonNil    // guaranteed to be non-nil
 	_, nodeTransient // storage can be reused immediately after this statement
 	_, nodeBounded   // bounds check unnecessary
-	_, nodeAddable   // addressable
 	_, nodeHasCall   // expression contains a function call
 	_, nodeLikely    // if statement condition likely
 	_, nodeHasVal    // node.E contains a Val
@@ -181,7 +180,6 @@ func (n *Node) Colas() bool                 { return n.flags&nodeColas != 0 }
 func (n *Node) NonNil() bool                { return n.flags&nodeNonNil != 0 }
 func (n *Node) Transient() bool             { return n.flags&nodeTransient != 0 }
 func (n *Node) Bounded() bool               { return n.flags&nodeBounded != 0 }
-func (n *Node) Addable() bool               { return n.flags&nodeAddable != 0 }
 func (n *Node) HasCall() bool               { return n.flags&nodeHasCall != 0 }
 func (n *Node) Likely() bool                { return n.flags&nodeLikely != 0 }
 func (n *Node) HasVal() bool                { return n.flags&nodeHasVal != 0 }
@@ -208,7 +206,6 @@ func (n *Node) SetColas(b bool)                 { n.flags.set(nodeColas, b) }
 func (n *Node) SetNonNil(b bool)                { n.flags.set(nodeNonNil, b) }
 func (n *Node) SetTransient(b bool)             { n.flags.set(nodeTransient, b) }
 func (n *Node) SetBounded(b bool)               { n.flags.set(nodeBounded, b) }
-func (n *Node) SetAddable(b bool)               { n.flags.set(nodeAddable, b) }
 func (n *Node) SetHasCall(b bool)               { n.flags.set(nodeHasCall, b) }
 func (n *Node) SetLikely(b bool)                { n.flags.set(nodeLikely, b) }
 func (n *Node) SetHasVal(b bool)                { n.flags.set(nodeHasVal, b) }

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

@@ -564,7 +564,6 @@ opswitch:
 		n = mkcall("gorecover", n.Type, init, nod(OADDR, nodfp, nil))
 
 	case OCLOSUREVAR, OCFUNC:
-		n.SetAddable(true)
 
 	case OCALLINTER, OCALLFUNC, OCALLMETH:
 		if n.Op == OCALLINTER {