mirror of
https://github.com/golang/go
synced 2024-11-23 12:50:12 -07:00
c8057d8569
if q != nil {
p = &q.f
}
Which gets rewritten to a conditional move:
tmp := &q.f
p = Select q!=nil, tmp, p
Unfortunately, we can't compute &q.f before we've checked if q is nil,
because if it is nil, &q.f is an invalid pointer (if f's offset is
nonzero but small).
Normally this is not a problem because the tmp variable above
immediately dies, and is thus not live across any safepoint. However,
if later there is another &q.f computation, those two computations are
CSEd, causing tmp to be used at both use points. That will extend
tmp's lifetime, possibly across a call.
Fixes #56990
Change-Id: I3ea31be93feae04fbe3304cb11323194c5df3879
Reviewed-on: https://go-review.googlesource.com/c/go/+/454155
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
120 lines
2.3 KiB
Go
120 lines
2.3 KiB
Go
// run
|
|
|
|
// 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
|
|
|
|
import (
|
|
"fmt"
|
|
"path/filepath"
|
|
"testing"
|
|
)
|
|
|
|
var t *testing.T
|
|
|
|
type TypeMeta struct {
|
|
Kind string
|
|
APIVersion string
|
|
}
|
|
|
|
type ObjectMeta struct {
|
|
Name string `json:"name,omitempty" protobuf:"bytes,1,opt,name=name"`
|
|
GenerateName string `json:"generateName,omitempty" protobuf:"bytes,2,opt,name=generateName"`
|
|
Namespace string `json:"namespace,omitempty" protobuf:"bytes,3,opt,name=namespace"`
|
|
SelfLink string `json:"selfLink,omitempty" protobuf:"bytes,4,opt,name=selfLink"`
|
|
}
|
|
|
|
type ConfigSpec struct {
|
|
Disks []DiskSpec
|
|
StorageClass string
|
|
}
|
|
|
|
type DiskSpec struct {
|
|
Name string
|
|
Size string
|
|
StorageClass string
|
|
Annotations map[string]string
|
|
VolumeName string
|
|
}
|
|
|
|
// Config is the Schema for the configs API.
|
|
type Config struct {
|
|
TypeMeta
|
|
ObjectMeta
|
|
|
|
Spec ConfigSpec
|
|
}
|
|
|
|
func findDiskSize(diskSpec *DiskSpec, configSpec *ConfigSpec) string {
|
|
t.Log(fmt.Sprintf("Hello World"))
|
|
return diskSpec.Size
|
|
}
|
|
|
|
func findStorageClassName(diskSpec *DiskSpec, configSpec *ConfigSpec) *string {
|
|
if diskSpec.StorageClass != "" {
|
|
return &diskSpec.StorageClass
|
|
}
|
|
|
|
if configSpec != nil {
|
|
for _, d := range configSpec.Disks {
|
|
if d.Name == diskSpec.Name {
|
|
if d.StorageClass != "" {
|
|
return &d.StorageClass
|
|
}
|
|
break
|
|
}
|
|
}
|
|
|
|
if configSpec.StorageClass != "" {
|
|
return &configSpec.StorageClass
|
|
}
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func Bar(config *Config) *ConfigSpec {
|
|
var configSpec *ConfigSpec
|
|
if config != nil {
|
|
configSpec = &config.Spec
|
|
}
|
|
return configSpec
|
|
}
|
|
|
|
func Foo(diskSpec DiskSpec, config *Config) {
|
|
cs := Bar(config)
|
|
_ = findDiskSize(&diskSpec, cs)
|
|
cs = Bar(config)
|
|
_ = findStorageClassName(&diskSpec, cs)
|
|
|
|
}
|
|
|
|
func TestPanic(tt *testing.T) {
|
|
t = tt
|
|
myarray := []string{filepath.Join("..", "config", "crd", "bases")}
|
|
|
|
for i := 0; i < 1000; i++ {
|
|
Foo(DiskSpec{
|
|
Name: "DataDisk",
|
|
Size: "1Gi",
|
|
}, nil)
|
|
}
|
|
|
|
t.Log(myarray)
|
|
}
|
|
|
|
// Hack to run tests in a playground
|
|
func matchString(a, b string) (bool, error) {
|
|
return a == b, nil
|
|
}
|
|
func main() {
|
|
testSuite := []testing.InternalTest{
|
|
{
|
|
Name: "TestPanic",
|
|
F: TestPanic,
|
|
},
|
|
}
|
|
testing.Main(matchString, testSuite, nil, nil)
|
|
}
|