cmd/compile: move Node.Initorder to flags

Grand savings: 6 bits.

Change-Id: I364be54cc41534689e01672ed0fe2c10a560d3d4
Reviewed-on: https://go-review.googlesource.com/41794
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

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

@@ -55,7 +55,7 @@ func init1(n *Node, out *[]*Node) {
 	switch n.Class {
 	case PEXTERN, PFUNC:
 	default:
-		if isblank(n) && n.Name.Curfn == nil && n.Name.Defn != nil && n.Name.Defn.Initorder == InitNotStarted {
+		if isblank(n) && n.Name.Curfn == nil && n.Name.Defn != nil && n.Name.Defn.Initorder() == InitNotStarted {
 			// blank names initialization is part of init() but not
 			// when they are inside a function.
 			break
@@ -63,10 +63,10 @@ func init1(n *Node, out *[]*Node) {
 		return
 	}
 
-	if n.Initorder == InitDone {
+	if n.Initorder() == InitDone {
 		return
 	}
-	if n.Initorder == InitPending {
+	if n.Initorder() == InitPending {
 		// Since mutually recursive sets of functions are allowed,
 		// we don't necessarily raise an error if n depends on a node
 		// which is already waiting for its dependencies to be visited.
@@ -95,7 +95,7 @@ func init1(n *Node, out *[]*Node) {
 	}
 
 	// reached a new unvisited node.
-	n.Initorder = InitPending
+	n.SetInitorder(InitPending)
 	initlist = append(initlist, n)
 
 	// make sure that everything n depends on is initialized.
@@ -133,10 +133,10 @@ func init1(n *Node, out *[]*Node) {
 			}
 
 		case OAS2FUNC, OAS2MAPR, OAS2DOTTYPE, OAS2RECV:
-			if defn.Initorder == InitDone {
+			if defn.Initorder() == InitDone {
 				break
 			}
-			defn.Initorder = InitPending
+			defn.SetInitorder(InitPending)
 			for _, n2 := range defn.Rlist.Slice() {
 				init1(n2, out)
 			}
@@ -144,7 +144,7 @@ func init1(n *Node, out *[]*Node) {
 				Dump("nonstatic", defn)
 			}
 			*out = append(*out, defn)
-			defn.Initorder = InitDone
+			defn.SetInitorder(InitDone)
 		}
 	}
 
@@ -155,7 +155,7 @@ func init1(n *Node, out *[]*Node) {
 	initlist[last] = nil // allow GC
 	initlist = initlist[:last]
 
-	n.Initorder = InitDone
+	n.SetInitorder(InitDone)
 	return
 }
 
@@ -197,7 +197,7 @@ func foundinitloop(node, visited *Node) {
 
 // recurse over n, doing init1 everywhere.
 func init2(n *Node, out *[]*Node) {
-	if n == nil || n.Initorder == InitDone {
+	if n == nil || n.Initorder() == InitDone {
 		return
 	}
 

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

@@ -59,7 +59,6 @@ type Node struct {
 	Etype     types.EType // op for OASOP, etype for OTYPE, exclam for export, 6g saved reg, ChanDir for OTCHAN, for OINDEXMAP 1=LHS,0=RHS
 	Class     Class       // PPARAM, PAUTO, PEXTERN, etc
 	Typecheck uint8       // tracks state during typechecking; 2 == loop detected
-	Initorder uint8
 }
 
 // IsAutoTmp indicates if n was created by the compiler as a temporary,
@@ -74,6 +73,8 @@ func (n *Node) IsAutoTmp() bool {
 const (
 	nodeWalkdef, _   = iota, 1 << iota // tracks state during typecheckdef; 2 == loop detected; two bits
 	_, _                               // second nodeWalkdef bit
+	nodeInitorder, _                   // tracks state during init1; two bits
+	_, _                               // second nodeInitorder bit
 	_, nodeHasBreak
 	_, nodeIsClosureVar
 	_, nodeIsOutputParamHeapAddr
@@ -98,6 +99,7 @@ const (
 )
 
 func (n *Node) Walkdef() uint8   { return n.flags.get2(nodeWalkdef) }
+func (n *Node) Initorder() uint8 { return n.flags.get2(nodeInitorder) }
 
 func (n *Node) HasBreak() bool              { return n.flags&nodeHasBreak != 0 }
 func (n *Node) IsClosureVar() bool          { return n.flags&nodeIsClosureVar != 0 }
@@ -122,6 +124,7 @@ func (n *Node) HasOpt() bool                { return n.flags&nodeHasOpt != 0 }
 func (n *Node) Embedded() bool              { return n.flags&nodeEmbedded != 0 }
 
 func (n *Node) SetWalkdef(b uint8)   { n.flags.set2(nodeWalkdef, b) }
+func (n *Node) SetInitorder(b uint8) { n.flags.set2(nodeInitorder, b) }
 
 func (n *Node) SetHasBreak(b bool)              { n.flags.set(nodeHasBreak, b) }
 func (n *Node) SetIsClosureVar(b bool)          { n.flags.set(nodeIsClosureVar, b) }