diff --git a/src/cmd/compile/internal/walk/switch.go b/src/cmd/compile/internal/walk/switch.go
index 7829d93373..141d2e5e05 100644
--- a/src/cmd/compile/internal/walk/switch.go
+++ b/src/cmd/compile/internal/walk/switch.go
@@ -318,15 +318,7 @@ func walkSwitchType(sw *ir.SwitchStmt) {
 	sw.Compiled.Append(ifNil)
 
 	// Load hash from type or itab.
-	dotHash := ir.NewSelectorExpr(base.Pos, ir.ODOTPTR, itab, nil)
-	dotHash.SetType(types.Types[types.TUINT32])
-	dotHash.SetTypecheck(1)
-	if s.facename.Type().IsEmptyInterface() {
-		dotHash.Offset = int64(2 * types.PtrSize) // offset of hash in runtime._type
-	} else {
-		dotHash.Offset = int64(2 * types.PtrSize) // offset of hash in runtime.itab
-	}
-	dotHash.SetBounded(true) // guaranteed not to fault
+	dotHash := typeHashFieldOf(base.Pos, itab)
 	s.hashname = copyExpr(dotHash, dotHash.Type(), &sw.Compiled)
 
 	br := ir.NewBranchStmt(base.Pos, ir.OBREAK, nil)
@@ -409,6 +401,32 @@ func walkSwitchType(sw *ir.SwitchStmt) {
 	walkStmtList(sw.Compiled)
 }
 
+// typeHashFieldOf returns an expression to select the type hash field
+// from an interface's descriptor word (whether a *runtime._type or
+// *runtime.itab pointer).
+func typeHashFieldOf(pos src.XPos, itab *ir.UnaryExpr) *ir.SelectorExpr {
+	if itab.Op() != ir.OITAB {
+		base.Fatalf("expected OITAB, got %v", itab.Op())
+	}
+	var hashField *types.Field
+	if itab.X.Type().IsEmptyInterface() {
+		// runtime._type's hash field
+		if rtypeHashField == nil {
+			rtypeHashField = runtimeField("hash", int64(2*types.PtrSize), types.Types[types.TUINT32])
+		}
+		hashField = rtypeHashField
+	} else {
+		// runtime.itab's hash field
+		if itabHashField == nil {
+			itabHashField = runtimeField("hash", int64(2*types.PtrSize), types.Types[types.TUINT32])
+		}
+		hashField = itabHashField
+	}
+	return boundedDotPtr(pos, itab, hashField)
+}
+
+var rtypeHashField, itabHashField *types.Field
+
 // A typeSwitch walks a type switch.
 type typeSwitch struct {
 	// Temporary variables (i.e., ONAMEs) used by type switch dispatch logic:
diff --git a/src/cmd/compile/internal/walk/walk.go b/src/cmd/compile/internal/walk/walk.go
index 9dda367b4d..6def35ef24 100644
--- a/src/cmd/compile/internal/walk/walk.go
+++ b/src/cmd/compile/internal/walk/walk.go
@@ -539,12 +539,31 @@ func calcHasCall(n ir.Node) bool {
 
 // itabType loads the _type field from a runtime.itab struct.
 func itabType(itab ir.Node) ir.Node {
-	typ := ir.NewSelectorExpr(base.Pos, ir.ODOTPTR, itab, nil)
-	typ.SetType(types.NewPtr(types.Types[types.TUINT8]))
-	typ.SetTypecheck(1)
-	typ.Offset = int64(types.PtrSize) // offset of _type in runtime.itab
-	typ.SetBounded(true)              // guaranteed not to fault
-	return typ
+	if itabTypeField == nil {
+		// runtime.itab's _type field
+		itabTypeField = runtimeField("_type", int64(types.PtrSize), types.NewPtr(types.Types[types.TUINT8]))
+	}
+	return boundedDotPtr(base.Pos, itab, itabTypeField)
+}
+
+var itabTypeField *types.Field
+
+// boundedDotPtr returns a selector expression representing ptr.field
+// and omits nil-pointer checks for ptr.
+func boundedDotPtr(pos src.XPos, ptr ir.Node, field *types.Field) *ir.SelectorExpr {
+	sel := ir.NewSelectorExpr(pos, ir.ODOTPTR, ptr, field.Sym)
+	sel.Selection = field
+	sel.Offset = field.Offset
+	sel.SetType(field.Type)
+	sel.SetTypecheck(1)
+	sel.SetBounded(true) // guaranteed not to fault
+	return sel
+}
+
+func runtimeField(name string, offset int64, typ *types.Type) *types.Field {
+	f := types.NewField(src.NoXPos, ir.Pkgs.Runtime.Lookup(name), typ)
+	f.Offset = offset
+	return f
 }
 
 // ifaceData loads the data field from an interface.