cmd/compile: further sinit.go cleanup

Follow-up to CL 20674.

Passes toolstash -cmp.

Change-Id: I065fd4cd80d996c1e6566773189401ca4630c1ca
Reviewed-on: https://go-review.googlesource.com/20692
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dave Cheney <dave@cheney.net>

diff --git a/src/cmd/compile/internal/gc/sinit.go b/src/cmd/compile/internal/gc/sinit.go
index fa8666e0955a78a10c02bf303f5bb2f22694d04d..ca5d35e87faa92a3b0d8b7201e2658bfba58552a 100644 (file)
--- a/src/cmd/compile/internal/gc/sinit.go
+++ b/src/cmd/compile/internal/gc/sinit.go
@@ -514,7 +514,7 @@ func isliteral(n *Node) bool {
        return n.Op == OLITERAL && n.Val().Ctype() != CTNIL
 }
 
-func simplename(n *Node) bool {
+func (n *Node) isSimpleName() bool {
        return n.Op == ONAME && n.Addable && n.Class&PHEAP == 0 && n.Class != PPARAMREF
 }
 
@@ -1045,7 +1045,7 @@ func anylit(ctxt int, n *Node, var_ *Node, init *Nodes) {
                        Fatalf("anylit: not struct")
                }
 
-               if simplename(var_) && n.List.Len() > 4 {
+               if var_.isSimpleName() && n.List.Len() > 4 {
                        if ctxt == 0 {
                                // lay out static data
                                vstat := staticname(t, ctxt)
@@ -1071,7 +1071,7 @@ func anylit(ctxt int, n *Node, var_ *Node, init *Nodes) {
                }
 
                // initialize of not completely specified
-               if simplename(var_) || n.List.Len() < structcount(t) {
+               if var_.isSimpleName() || n.List.Len() < structcount(t) {
                        a := Nod(OAS, var_, nil)
                        typecheck(&a, Etop)
                        walkexpr(&a, init)
@@ -1089,7 +1089,7 @@ func anylit(ctxt int, n *Node, var_ *Node, init *Nodes) {
                        break
                }
 
-               if simplename(var_) && n.List.Len() > 4 {
+               if var_.isSimpleName() && n.List.Len() > 4 {
                        if ctxt == 0 {
                                // lay out static data
                                vstat := staticname(t, ctxt)
@@ -1115,7 +1115,7 @@ func anylit(ctxt int, n *Node, var_ *Node, init *Nodes) {
                }
 
                // initialize of not completely specified
-               if simplename(var_) || int64(n.List.Len()) < t.Bound {
+               if var_.isSimpleName() || int64(n.List.Len()) < t.Bound {
                        a := Nod(OAS, var_, nil)
                        typecheck(&a, Etop)
                        walkexpr(&a, init)
@@ -1141,7 +1141,7 @@ func oaslit(n *Node, init *Nodes) bool {
                // not a special composit literal assignment
                return false
        }
-       if !simplename(n.Left) {
+       if !n.Left.isSimpleName() {
                // not a special composit literal assignment
                return false
        }
@@ -1337,85 +1337,79 @@ func isvaluelit(n *Node) bool {
 // gen_as_init attempts to emit static data for n and reports whether it succeeded.
 // If reportOnly is true, it does not emit static data and does not modify the AST.
 func gen_as_init(n *Node, reportOnly bool) bool {
-       var nr *Node
-       var nl *Node
-       var nam Node
+       success := genAsInitNoCheck(n, reportOnly)
+       if !success && n.Dodata == 2 {
+               Dump("\ngen_as_init", n)
+               Fatalf("gen_as_init couldn't make data statement")
+       }
+       return success
+}
 
+func genAsInitNoCheck(n *Node, reportOnly bool) bool {
        if n.Dodata == 0 {
-               goto no
+               return false
        }
 
-       nr = n.Right
-       nl = n.Left
+       nr := n.Right
+       nl := n.Left
        if nr == nil {
                var nam Node
-               if !stataddr(&nam, nl) {
-                       goto no
-               }
-               if nam.Class != PEXTERN {
-                       goto no
-               }
-               return true
+               return stataddr(&nam, nl) && nam.Class == PEXTERN
        }
 
        if nr.Type == nil || !Eqtype(nl.Type, nr.Type) {
-               goto no
-       }
-
-       if !stataddr(&nam, nl) {
-               goto no
+               return false
        }
 
-       if nam.Class != PEXTERN {
-               goto no
+       var nam Node
+       if !stataddr(&nam, nl) || nam.Class != PEXTERN {
+               return false
        }
 
        switch nr.Op {
        default:
-               goto no
+               return false
 
        case OCONVNOP:
                nr = nr.Left
                if nr == nil || nr.Op != OSLICEARR {
-                       goto no
+                       return false
                }
                fallthrough
 
-               // fall through
        case OSLICEARR:
-               if nr.Right.Op == OKEY && nr.Right.Left == nil && nr.Right.Right == nil {
-                       nr = nr.Left
-                       nl := nr
-                       if nr == nil || nr.Op != OADDR {
-                               goto no
-                       }
-                       nr = nr.Left
-                       if nr == nil || nr.Op != ONAME {
-                               goto no
-                       }
-
-                       // nr is the array being converted to a slice
-                       if nr.Type == nil || nr.Type.Etype != TARRAY || nr.Type.Bound < 0 {
-                               goto no
-                       }
+               if nr.Right.Op != OKEY || nr.Right.Left != nil || nr.Right.Right != nil {
+                       return false
+               }
+               nr = nr.Left
+               if nr == nil || nr.Op != OADDR {
+                       return false
+               }
+               ptr := nr
+               nr = nr.Left
+               if nr == nil || nr.Op != ONAME {
+                       return false
+               }
 
-                       if !reportOnly {
-                               nam.Xoffset += int64(Array_array)
-                               gdata(&nam, nl, int(Types[Tptr].Width))
+               // nr is the array being converted to a slice
+               if nr.Type == nil || nr.Type.Etype != TARRAY || nr.Type.Bound < 0 {
+                       return false
+               }
 
-                               nam.Xoffset += int64(Array_nel) - int64(Array_array)
-                               var nod1 Node
-                               Nodconst(&nod1, Types[TINT], nr.Type.Bound)
-                               gdata(&nam, &nod1, Widthint)
+               if !reportOnly {
+                       nam.Xoffset += int64(Array_array)
+                       gdata(&nam, ptr, Widthptr)
 
-                               nam.Xoffset += int64(Array_cap) - int64(Array_nel)
-                               gdata(&nam, &nod1, Widthint)
-                       }
+                       nam.Xoffset += int64(Array_nel) - int64(Array_array)
+                       var nod1 Node
+                       Nodconst(&nod1, Types[TINT], nr.Type.Bound)
+                       gdata(&nam, &nod1, Widthint)
 
-                       return true
+                       nam.Xoffset += int64(Array_cap) - int64(Array_nel)
+                       gdata(&nam, &nod1, Widthint)
                }
 
-               goto no
+               return true
 
        case OLITERAL:
                break
@@ -1423,7 +1417,7 @@ func gen_as_init(n *Node, reportOnly bool) bool {
 
        switch nr.Type.Etype {
        default:
-               goto no
+               return false
 
        case TBOOL, TINT8, TUINT8, TINT16, TUINT16,
                TINT32, TUINT32, TINT64, TUINT64,
@@ -1446,12 +1440,4 @@ func gen_as_init(n *Node, reportOnly bool) bool {
        }
 
        return true
-
-no:
-       if n.Dodata == 2 {
-               Dump("\ngen_as_init", n)
-               Fatalf("gen_as_init couldnt make data statement")
-       }
-
-       return false
 }