[release-branch.go1.18] cmd/compile: fix missing dict pass for type assertions

cuonglm · heschi · commit 460a93b54af4 · 2022-07-06T19:31:41.000Z
For type assertions, if either src or dst type has shape, we must convert them to dynamic type assertions. Fixes #53357 Change-Id: Ia3362fa67c011febcbdb5b26f856d081b5c366de Reviewed-on: https://go-review.googlesource.com/c/go/+/411617 Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com> TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Matthew Dempsky <mdempsky@google.com> Reviewed-by: Cherry Mui <cherryyz@google.com> Reviewed-by: Keith Randall <khr@golang.org> Reviewed-on: https://go-review.googlesource.com/c/go/+/411934 Reviewed-by: Keith Randall <khr@google.com>
diff --git a/src/cmd/compile/internal/noder/stencil.go b/src/cmd/compile/internal/noder/stencil.go
@@ -1297,10 +1297,10 @@ func (g *genInst) dictPass(info *instInfo) {
 				m = convertUsingDictionary(info, info.dictParam, m.Pos(), mce.X, m, m.Type(), false)
 			}
 		case ir.ODOTTYPE, ir.ODOTTYPE2:
-			if !m.Type().HasShape() {
+			dt := m.(*ir.TypeAssertExpr)
+			if !dt.Type().HasShape() && !dt.X.Type().HasShape() {
 				break
 			}
-			dt := m.(*ir.TypeAssertExpr)
 			var rt ir.Node
 			if dt.Type().IsInterface() || dt.X.Type().IsEmptyInterface() {
 				ix := findDictType(info, m.Type())
diff --git a/test/typeparam/issue53309.go b/test/typeparam/issue53309.go
@@ -0,0 +1,42 @@
+// run -gcflags=-G=3
+
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+type TaskInput interface {
+	deps() []*taskDefinition
+}
+
+type Value[T any] interface {
+	metaValue
+}
+
+type metaValue interface {
+	TaskInput
+}
+
+type taskDefinition struct {
+}
+
+type taskResult struct {
+	task *taskDefinition
+}
+
+func (tr *taskResult) deps() []*taskDefinition {
+	return nil
+}
+
+func use[T any](v Value[T]) {
+	_, ok := v.(*taskResult)
+	if !ok {
+		panic("output must be *taskResult")
+	}
+}
+
+func main() {
+	tr := &taskResult{&taskDefinition{}}
+	use(Value[string](tr))
+}

Original file line number	Diff line number	Diff line change
`@@ -1297,10 +1297,10 @@ func (g genInst) dictPass(info instInfo) {`
`1297`	`1297`	`m = convertUsingDictionary(info, info.dictParam, m.Pos(), mce.X, m, m.Type(), false)`
`1298`	`1298`	`}`
`1299`	`1299`	`case ir.ODOTTYPE, ir.ODOTTYPE2:`
`1300`		`- if !m.Type().HasShape() {`
	`1300`	`+ dt := m.(*ir.TypeAssertExpr)`
	`1301`	`+ if !dt.Type().HasShape() && !dt.X.Type().HasShape() {`
`1301`	`1302`	`break`
`1302`	`1303`	`}`
`1303`		`- dt := m.(*ir.TypeAssertExpr)`
`1304`	`1304`	`var rt ir.Node`
`1305`	`1305`	`if dt.Type().IsInterface() \|\| dt.X.Type().IsEmptyInterface() {`
`1306`	`1306`	`ix := findDictType(info, m.Type())`