diff options
Diffstat (limited to 'src/cmd/link/internal/ld/testdata/deadcode')
3 files changed, 116 insertions, 0 deletions
diff --git a/src/cmd/link/internal/ld/testdata/deadcode/ifacemethod5.go b/src/cmd/link/internal/ld/testdata/deadcode/ifacemethod5.go new file mode 100644 index 0000000000..2f0bdcc745 --- /dev/null +++ b/src/cmd/link/internal/ld/testdata/deadcode/ifacemethod5.go @@ -0,0 +1,33 @@ +// Copyright 2023 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. + +// Like ifacemethod2.go, this tests that a method *is* live +// if the type is "indirectly" converted to an interface +// using reflection with a method descriptor as intermediate. +// However, it uses MethodByName() with a constant name of +// a method to look up. This does not disable the DCE like +// Method(0) does. + +package main + +import "reflect" + +type S int + +func (s S) M() { println("S.M") } + +type I interface{ M() } + +type T float64 + +func (t T) F(s S) {} + +func main() { + var t T + meth, _ := reflect.TypeOf(t).MethodByName("F") + ft := meth.Type + at := ft.In(1) + v := reflect.New(at).Elem() + v.Interface().(I).M() +} diff --git a/src/cmd/link/internal/ld/testdata/deadcode/ifacemethod6.go b/src/cmd/link/internal/ld/testdata/deadcode/ifacemethod6.go new file mode 100644 index 0000000000..7eb9419ef1 --- /dev/null +++ b/src/cmd/link/internal/ld/testdata/deadcode/ifacemethod6.go @@ -0,0 +1,31 @@ +// Copyright 2023 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. + +// This test only uses MethodByName() with constant names +// of methods to look up. These methods need to be kept, +// but other methods must be eliminated. + +package main + +import "reflect" + +type S int + +func (s S) M() { println("S.M") } + +func (s S) N() { println("S.N") } + +type T float64 + +func (t T) F(s S) {} + +func main() { + var t T + meth, _ := reflect.TypeOf(t).MethodByName("F") + ft := meth.Type + at := ft.In(1) + v := reflect.New(at).Elem() + methV := v.MethodByName("M") + methV.Call([]reflect.Value{v}) +} diff --git a/src/cmd/link/internal/ld/testdata/deadcode/structof_funcof.go b/src/cmd/link/internal/ld/testdata/deadcode/structof_funcof.go new file mode 100644 index 0000000000..bec5f25fc0 --- /dev/null +++ b/src/cmd/link/internal/ld/testdata/deadcode/structof_funcof.go @@ -0,0 +1,52 @@ +// Copyright 2023 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. + +// Methods of reflect.rtype use StructOf and FuncOf which in turn depend on +// reflect.Value.Method. StructOf and FuncOf must not disable the DCE. + +package main + +import "reflect" + +type S int + +func (s S) M() { println("S.M") } + +func (s S) N() { println("S.N") } + +type T float64 + +func (t T) F(s S) {} + +func useStructOf() { + t := reflect.StructOf([]reflect.StructField{ + { + Name: "X", + Type: reflect.TypeOf(int(0)), + }, + }) + println(t.Name()) +} + +func useFuncOf() { + t := reflect.FuncOf( + []reflect.Type{reflect.TypeOf(int(0))}, + []reflect.Type{reflect.TypeOf(int(0))}, + false, + ) + println(t.Name()) +} + +func main() { + useStructOf() + useFuncOf() + + var t T + meth, _ := reflect.TypeOf(t).MethodByName("F") + ft := meth.Type + at := ft.In(1) + v := reflect.New(at).Elem() + methV := v.MethodByName("M") + methV.Call([]reflect.Value{v}) +} |