cmd/compile: reduce stutter

This is follow-up 1 of 3 to CL 20959.

Passes toolstash -cmp.

Change-Id: I9bddf7d88333fa4755e03ff8a034a35bd01b7855
Reviewed-on: https://go-review.googlesource.com/21052
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/closure.go

@@ -457,9 +457,7 @@ func walkclosure(func_ *Node, init *Nodes) *Node {
 		delete(prealloc, func_)
 	}
 
-	clos = walkexpr(clos, init)
-
-	return clos
+	return walkexpr(clos, init)
 }
 
 func typecheckpartialcall(fn *Node, sym *Sym) {
@@ -662,7 +660,5 @@ func walkpartialcall(n *Node, init *Nodes) *Node {
 		delete(prealloc, n)
 	}
 
-	clos = walkexpr(clos, init)
-
-	return clos
+	return walkexpr(clos, init)
 }

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

@@ -143,8 +143,7 @@ func convlit1(n *Node, t *Type, explicit bool) *Node {
 		// target is invalid type for a constant?  leave alone.
 	case OLITERAL:
 		if !okforconst[t.Etype] && n.Type.Etype != TNIL {
-			n = defaultlit(n, nil)
-			return n
+			return defaultlit(n, nil)
 		}
 
 	case OLSH, ORSH:
@@ -204,9 +203,7 @@ func convlit1(n *Node, t *Type, explicit bool) *Node {
 			n.Type = t
 			return n
 		}
-
-		n = defaultlit(n, nil)
-		return n
+		return defaultlit(n, nil)
 	}
 
 	switch ct {
@@ -1264,8 +1261,7 @@ func defaultlit(n *Node, t *Type) *Node {
 	switch ctype {
 	default:
 		if t != nil {
-			n = convlit(n, t)
-			return n
+			return convlit(n, t)
 		}
 
 		if n.Val().Ctype() == CTNIL {

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

@@ -902,12 +902,11 @@ func esc(e *EscState, n *Node, up *Node) {
 
 		// Link addresses of captured variables to closure.
 	case OCLOSURE:
-		var a *Node
 		for _, v := range n.Func.Cvars.Slice() {
 			if v.Op == OXXX { // unnamed out argument; see dcl.go:/^funcargs
 				continue
 			}
-			a = v.Name.Param.Closure
+			a := v.Name.Param.Closure
 			if !v.Name.Byval {
 				a = Nod(OADDR, a, nil)
 				a.Lineno = v.Lineno

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

@@ -225,8 +225,7 @@ func reexportdep(n *Node) {
 }
 
 func dumpexportconst(s *Sym) {
-	n := s.Def
-	n = typecheck(n, Erv)
+	n := typecheck(s.Def, Erv)
 	if n == nil || n.Op != OLITERAL {
 		Fatalf("dumpexportconst: oconst nil: %v", s)
 	}

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

@@ -292,8 +292,7 @@ func inlconv2stmt(n *Node) {
 // 	n.Left = inlconv2expr(n.Left)
 func inlconv2expr(n *Node) *Node {
 	r := n.Rlist.First()
-	r = addinit(r, append(n.Ninit.Slice(), n.Nbody.Slice()...))
-	return r
+	return addinit(r, append(n.Ninit.Slice(), n.Nbody.Slice()...))
 }
 
 // Turn the rlist (with the return values) of the OINLCALL in
@@ -509,8 +508,7 @@ func tinlvar(t *Field) *Node {
 		return t.Nname.Name.Inlvar
 	}
 
-	nblank = typecheck(nblank, Erv|Easgn)
-	return nblank
+	return typecheck(nblank, Erv|Easgn)
 }
 
 var inlgen int