cmd/compile: add TestIntendedInlining from runtime

Move it from the runtime package, as we will soon add more packages and
functions for it to check.

The test used the testEnv func, which cleaned certain environment
variables from a command, so it was moved to internal/testenv under a
more descriptive (and less ambiguous) name. Add a simple godoc to it
too.

For #21851.

Change-Id: I6f39c1f23b45377718355fafe66ffd87047d8ab6
Reviewed-on: https://go-review.googlesource.com/63550
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>

src/cmd/compile/internal/gc/inl_test.go

+// Copyright 2017 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 gc
+
+import (
+	"bytes"
+	"internal/testenv"
+	"os/exec"
+	"testing"
+)
+
+// TestIntendedInlining tests that specific runtime functions are inlined.
+// This allows refactoring for code clarity and re-use without fear that
+// changes to the compiler will cause silent performance regressions.
+func TestIntendedInlining(t *testing.T) {
+	if testing.Short() && testenv.Builder() == "" {
+		t.Skip("skipping in short mode")
+	}
+	testenv.MustHaveGoRun(t)
+	t.Parallel()
+
+	// want is the list of function names that should be inlined.
+	want := []string{"tophash", "add", "(*bmap).keys", "bucketShift", "bucketMask"}
+
+	m := make(map[string]bool, len(want))
+	for _, s := range want {
+		m[s] = true
+	}
+
+	cmd := testenv.CleanCmdEnv(exec.Command(testenv.GoToolPath(t), "build", "-a", "-gcflags=-m", "runtime"))
+	out, err := cmd.CombinedOutput()
+	if err != nil {
+		t.Logf("%s", out)
+		t.Fatal(err)
+	}
+	lines := bytes.Split(out, []byte{'\n'})
+	for _, x := range lines {
+		f := bytes.Split(x, []byte(": can inline "))
+		if len(f) < 2 {
+			continue
+		}
+		fn := bytes.TrimSpace(f[1])
+		delete(m, string(fn))
+	}
+
+	for s := range m {
+		t.Errorf("function %s not inlined", s)
+	}
+}

src/internal/testenv/testenv.go

@@ -209,3 +209,25 @@ func SkipFlakyNet(t *testing.T) {
 		t.Skip("skipping test on builder known to have frequent network failures")
 	}
 }
+
+// CleanCmdEnv will fill cmd.Env with the environment, excluding certain
+// variables that could modify the behavior of the Go tools such as
+// GODEBUG and GOTRACEBACK.
+func CleanCmdEnv(cmd *exec.Cmd) *exec.Cmd {
+	if cmd.Env != nil {
+		panic("environment already set")
+	}
+	for _, env := range os.Environ() {
+		// Exclude GODEBUG from the environment to prevent its output
+		// from breaking tests that are trying to parse other command output.
+		if strings.HasPrefix(env, "GODEBUG=") {
+			continue
+		}
+		// Exclude GOTRACEBACK for the same reason.
+		if strings.HasPrefix(env, "GOTRACEBACK=") {
+			continue
+		}
+		cmd.Env = append(cmd.Env, env)
+	}
+	return cmd
+}

src/runtime/crash_cgo_test.go

@@ -113,7 +113,7 @@ func TestCgoExternalThreadSIGPROF(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	got, err := testEnv(exec.Command(exe, "CgoExternalThreadSIGPROF")).CombinedOutput()
+	got, err := testenv.CleanCmdEnv(exec.Command(exe, "CgoExternalThreadSIGPROF")).CombinedOutput()
 	if err != nil {
 		t.Fatalf("exit status: %v\n%s", err, got)
 	}
@@ -136,7 +136,7 @@ func TestCgoExternalThreadSignal(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	got, err := testEnv(exec.Command(exe, "CgoExternalThreadSIGPROF")).CombinedOutput()
+	got, err := testenv.CleanCmdEnv(exec.Command(exe, "CgoExternalThreadSIGPROF")).CombinedOutput()
 	if err != nil {
 		t.Fatalf("exit status: %v\n%s", err, got)
 	}
@@ -203,14 +203,14 @@ func TestCgoCheckBytes(t *testing.T) {
 	const tries = 10
 	var tot1, tot2 time.Duration
 	for i := 0; i < tries; i++ {
-		cmd := testEnv(exec.Command(exe, "CgoCheckBytes"))
+		cmd := testenv.CleanCmdEnv(exec.Command(exe, "CgoCheckBytes"))
 		cmd.Env = append(cmd.Env, "GODEBUG=cgocheck=0", fmt.Sprintf("GO_CGOCHECKBYTES_TRY=%d", i))
 
 		start := time.Now()
 		cmd.Run()
 		d1 := time.Since(start)
 
-		cmd = testEnv(exec.Command(exe, "CgoCheckBytes"))
+		cmd = testenv.CleanCmdEnv(exec.Command(exe, "CgoCheckBytes"))
 		cmd.Env = append(cmd.Env, fmt.Sprintf("GO_CGOCHECKBYTES_TRY=%d", i))
 
 		start = time.Now()
@@ -283,7 +283,7 @@ func testCgoPprof(t *testing.T, buildArg, runArg string) {
 		t.Fatal(err)
 	}
 
-	got, err := testEnv(exec.Command(exe, runArg)).CombinedOutput()
+	got, err := testenv.CleanCmdEnv(exec.Command(exe, runArg)).CombinedOutput()
 	if err != nil {
 		if testenv.Builder() == "linux-amd64-alpine" {
 			// See Issue 18243 and Issue 19938.
@@ -295,7 +295,7 @@ func testCgoPprof(t *testing.T, buildArg, runArg string) {
 	defer os.Remove(fn)
 
 	for try := 0; try < 2; try++ {
-		cmd := testEnv(exec.Command(testenv.GoToolPath(t), "tool", "pprof", "-top", "-nodecount=1"))
+		cmd := testenv.CleanCmdEnv(exec.Command(testenv.GoToolPath(t), "tool", "pprof", "-top", "-nodecount=1"))
 		// Check that pprof works both with and without explicit executable on command line.
 		if try == 0 {
 			cmd.Args = append(cmd.Args, exe, fn)
@@ -359,7 +359,7 @@ func TestRaceProf(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	got, err := testEnv(exec.Command(exe, "CgoRaceprof")).CombinedOutput()
+	got, err := testenv.CleanCmdEnv(exec.Command(exe, "CgoRaceprof")).CombinedOutput()
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -388,7 +388,7 @@ func TestRaceSignal(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	got, err := testEnv(exec.Command(exe, "CgoRaceSignal")).CombinedOutput()
+	got, err := testenv.CleanCmdEnv(exec.Command(exe, "CgoRaceSignal")).CombinedOutput()
 	if err != nil {
 		t.Logf("%s\n", got)
 		t.Fatal(err)
@@ -431,7 +431,7 @@ func TestCatchPanic(t *testing.T) {
 	}
 
 	for _, early := range []bool{true, false} {
-		cmd := testEnv(exec.Command(exe, "CgoCatchPanic"))
+		cmd := testenv.CleanCmdEnv(exec.Command(exe, "CgoCatchPanic"))
 		// Make sure a panic results in a crash.
 		cmd.Env = append(cmd.Env, "GOTRACEBACK=crash")
 		if early {

src/runtime/crash_test.go

@@ -32,25 +32,6 @@ func TestMain(m *testing.M) {
 	os.Exit(status)
 }
 
-func testEnv(cmd *exec.Cmd) *exec.Cmd {
-	if cmd.Env != nil {
-		panic("environment already set")
-	}
-	for _, env := range os.Environ() {
-		// Exclude GODEBUG from the environment to prevent its output
-		// from breaking tests that are trying to parse other command output.
-		if strings.HasPrefix(env, "GODEBUG=") {
-			continue
-		}
-		// Exclude GOTRACEBACK for the same reason.
-		if strings.HasPrefix(env, "GOTRACEBACK=") {
-			continue
-		}
-		cmd.Env = append(cmd.Env, env)
-	}
-	return cmd
-}
-
 var testprog struct {
 	sync.Mutex
 	dir    string
@@ -70,7 +51,7 @@ func runTestProg(t *testing.T, binary, name string) string {
 		t.Fatal(err)
 	}
 
-	cmd := testEnv(exec.Command(exe, name))
+	cmd := testenv.CleanCmdEnv(exec.Command(exe, name))
 	var b bytes.Buffer
 	cmd.Stdout = &b
 	cmd.Stderr = &b
@@ -139,7 +120,7 @@ func buildTestProg(t *testing.T, binary string, flags ...string) (string, error)
 	exe := filepath.Join(testprog.dir, name+".exe")
 	cmd := exec.Command(testenv.GoToolPath(t), append([]string{"build", "-o", exe}, flags...)...)
 	cmd.Dir = "testdata/" + binary
-	out, err := testEnv(cmd).CombinedOutput()
+	out, err := testenv.CleanCmdEnv(cmd).CombinedOutput()
 	if err != nil {
 		target.err = fmt.Errorf("building %s %v: %v\n%s", binary, flags, err, out)
 		testprog.target[name] = target
@@ -158,14 +139,14 @@ var (
 func checkStaleRuntime(t *testing.T) {
 	staleRuntimeOnce.Do(func() {
 		// 'go run' uses the installed copy of runtime.a, which may be out of date.
-		out, err := testEnv(exec.Command(testenv.GoToolPath(t), "list", "-f", "{{.Stale}}", "runtime")).CombinedOutput()
+		out, err := testenv.CleanCmdEnv(exec.Command(testenv.GoToolPath(t), "list", "-f", "{{.Stale}}", "runtime")).CombinedOutput()
 		if err != nil {
 			staleRuntimeErr = fmt.Errorf("failed to execute 'go list': %v\n%v", err, string(out))
 			return
 		}
 		if string(out) != "false\n" {
 			t.Logf("go list -f {{.Stale}} runtime:\n%s", out)
-			out, err := testEnv(exec.Command(testenv.GoToolPath(t), "list", "-f", "{{.StaleReason}}", "runtime")).CombinedOutput()
+			out, err := testenv.CleanCmdEnv(exec.Command(testenv.GoToolPath(t), "list", "-f", "{{.StaleReason}}", "runtime")).CombinedOutput()
 			if err != nil {
 				t.Logf("go list -f {{.StaleReason}} failed: %v", err)
 			}
@@ -468,7 +449,7 @@ func TestMemPprof(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	got, err := testEnv(exec.Command(exe, "MemProf")).CombinedOutput()
+	got, err := testenv.CleanCmdEnv(exec.Command(exe, "MemProf")).CombinedOutput()
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -476,7 +457,7 @@ func TestMemPprof(t *testing.T) {
 	defer os.Remove(fn)
 
 	for try := 0; try < 2; try++ {
-		cmd := testEnv(exec.Command(testenv.GoToolPath(t), "tool", "pprof", "-alloc_space", "-top"))
+		cmd := testenv.CleanCmdEnv(exec.Command(testenv.GoToolPath(t), "tool", "pprof", "-alloc_space", "-top"))
 		// Check that pprof works both with and without explicit executable on command line.
 		if try == 0 {
 			cmd.Args = append(cmd.Args, exe, fn)
@@ -586,7 +567,7 @@ func TestPanicRace(t *testing.T) {
 	const tries = 10
 retry:
 	for i := 0; i < tries; i++ {
-		got, err := testEnv(exec.Command(exe, "PanicRace")).CombinedOutput()
+		got, err := testenv.CleanCmdEnv(exec.Command(exe, "PanicRace")).CombinedOutput()
 		if err == nil {
 			t.Logf("try %d: program exited successfully, should have failed", i+1)
 			continue

src/runtime/crash_unix_test.go

@@ -65,13 +65,13 @@ func TestCrashDumpsAllThreads(t *testing.T) {
 
 	cmd := exec.Command(testenv.GoToolPath(t), "build", "-o", "a.exe")
 	cmd.Dir = dir
-	out, err := testEnv(cmd).CombinedOutput()
+	out, err := testenv.CleanCmdEnv(cmd).CombinedOutput()
 	if err != nil {
 		t.Fatalf("building source: %v\n%s", err, out)
 	}
 
 	cmd = exec.Command(filepath.Join(dir, "a.exe"))
-	cmd = testEnv(cmd)
+	cmd = testenv.CleanCmdEnv(cmd)
 	cmd.Env = append(cmd.Env, "GOTRACEBACK=crash")
 
 	// Set GOGC=off. Because of golang.org/issue/10958, the tight
@@ -184,7 +184,7 @@ func TestPanicSystemstack(t *testing.T) {
 
 	t.Parallel()
 	cmd := exec.Command(os.Args[0], "testPanicSystemstackInternal")
-	cmd = testEnv(cmd)
+	cmd = testenv.CleanCmdEnv(cmd)
 	cmd.Env = append(cmd.Env, "GOTRACEBACK=crash")
 	pr, pw, err := os.Pipe()
 	if err != nil {
@@ -249,7 +249,7 @@ func TestSignalExitStatus(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	err = testEnv(exec.Command(exe, "SignalExitStatus")).Run()
+	err = testenv.CleanCmdEnv(exec.Command(exe, "SignalExitStatus")).Run()
 	if err == nil {
 		t.Error("test program succeeded unexpectedly")
 	} else if ee, ok := err.(*exec.ExitError); !ok {

src/runtime/runtime-gdb_test.go

@@ -132,7 +132,7 @@ func testGdbPython(t *testing.T, cgo bool) {
 
 	cmd := exec.Command(testenv.GoToolPath(t), "build", "-o", "a.exe")
 	cmd.Dir = dir
-	out, err := testEnv(cmd).CombinedOutput()
+	out, err := testenv.CleanCmdEnv(cmd).CombinedOutput()
 	if err != nil {
 		t.Fatalf("building source %v\n%s", err, out)
 	}
@@ -278,7 +278,7 @@ func TestGdbBacktrace(t *testing.T) {
 	}
 	cmd := exec.Command(testenv.GoToolPath(t), "build", "-o", "a.exe")
 	cmd.Dir = dir
-	out, err := testEnv(cmd).CombinedOutput()
+	out, err := testenv.CleanCmdEnv(cmd).CombinedOutput()
 	if err != nil {
 		t.Fatalf("building source %v\n%s", err, out)
 	}
@@ -348,7 +348,7 @@ func TestGdbAutotmpTypes(t *testing.T) {
 	}
 	cmd := exec.Command(testenv.GoToolPath(t), "build", "-gcflags=-N -l", "-o", "a.exe")
 	cmd.Dir = dir
-	out, err := testEnv(cmd).CombinedOutput()
+	out, err := testenv.CleanCmdEnv(cmd).CombinedOutput()
 	if err != nil {
 		t.Fatalf("building source %v\n%s", err, out)
 	}

src/runtime/runtime_test.go

@@ -5,10 +5,7 @@
 package runtime_test
 
 import (
-	"bytes"
-	"internal/testenv"
 	"io"
-	"os/exec"
 	. "runtime"
 	"runtime/debug"
 	"strings"
@@ -357,42 +354,3 @@ func TestVersion(t *testing.T) {
 		t.Fatalf("cr/nl in version: %q", vers)
 	}
 }
-
-// TestIntendedInlining tests that specific runtime functions are inlined.
-// This allows refactoring for code clarity and re-use without fear that
-// changes to the compiler will cause silent performance regressions.
-func TestIntendedInlining(t *testing.T) {
-	if testing.Short() && testenv.Builder() == "" {
-		t.Skip("skipping in short mode")
-	}
-	testenv.MustHaveGoRun(t)
-	t.Parallel()
-
-	// want is the list of function names that should be inlined.
-	want := []string{"tophash", "add", "(*bmap).keys", "bucketShift", "bucketMask"}
-
-	m := make(map[string]bool, len(want))
-	for _, s := range want {
-		m[s] = true
-	}
-
-	cmd := testEnv(exec.Command(testenv.GoToolPath(t), "build", "-a", "-gcflags=-m", "runtime"))
-	out, err := cmd.CombinedOutput()
-	if err != nil {
-		t.Logf("%s", out)
-		t.Fatal(err)
-	}
-	lines := bytes.Split(out, []byte{'\n'})
-	for _, x := range lines {
-		f := bytes.Split(x, []byte(": can inline "))
-		if len(f) < 2 {
-			continue
-		}
-		fn := bytes.TrimSpace(f[1])
-		delete(m, string(fn))
-	}
-
-	for s := range m {
-		t.Errorf("function %s not inlined", s)
-	}
-}