blob: 04b5fcc2837e46f5fdcf2340acc77f2783a93432 [file] [log] [blame]
// Copyright 2009 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 gosym
import (
"bytes"
"compress/gzip"
"debug/elf"
"internal/testenv"
"io"
"os"
"os/exec"
"path/filepath"
"runtime"
"strings"
"testing"
)
var (
pclineTempDir string
pclinetestBinary string
)
func dotest(t *testing.T) {
testenv.MustHaveGoBuild(t)
// For now, only works on amd64 platforms.
if runtime.GOARCH != "amd64" {
t.Skipf("skipping on non-AMD64 system %s", runtime.GOARCH)
}
// This test builds a Linux/AMD64 binary. Skipping in short mode if cross compiling.
if runtime.GOOS != "linux" && testing.Short() {
t.Skipf("skipping in short mode on non-Linux system %s", runtime.GOARCH)
}
var err error
pclineTempDir, err = os.MkdirTemp("", "pclinetest")
if err != nil {
t.Fatal(err)
}
pclinetestBinary = filepath.Join(pclineTempDir, "pclinetest")
cmd := exec.Command(testenv.GoToolPath(t), "build", "-o", pclinetestBinary)
cmd.Dir = "testdata"
cmd.Env = append(os.Environ(), "GOOS=linux")
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
if err := cmd.Run(); err != nil {
t.Fatal(err)
}
}
func endtest() {
if pclineTempDir != "" {
os.RemoveAll(pclineTempDir)
pclineTempDir = ""
pclinetestBinary = ""
}
}
// skipIfNotELF skips the test if we are not running on an ELF system.
// These tests open and examine the test binary, and use elf.Open to do so.
func skipIfNotELF(t *testing.T) {
switch runtime.GOOS {
case "dragonfly", "freebsd", "linux", "netbsd", "openbsd", "solaris", "illumos":
// OK.
default:
t.Skipf("skipping on non-ELF system %s", runtime.GOOS)
}
}
func getTable(t *testing.T) *Table {
f, tab := crack(os.Args[0], t)
f.Close()
return tab
}
func crack(file string, t *testing.T) (*elf.File, *Table) {
// Open self
f, err := elf.Open(file)
if err != nil {
t.Fatal(err)
}
return parse(file, f, t)
}
func parse(file string, f *elf.File, t *testing.T) (*elf.File, *Table) {
s := f.Section(".gosymtab")
if s == nil {
t.Skip("no .gosymtab section")
}
symdat, err := s.Data()
if err != nil {
f.Close()
t.Fatalf("reading %s gosymtab: %v", file, err)
}
pclndat, err := f.Section(".gopclntab").Data()
if err != nil {
f.Close()
t.Fatalf("reading %s gopclntab: %v", file, err)
}
pcln := NewLineTable(pclndat, f.Section(".text").Addr)
tab, err := NewTable(symdat, pcln)
if err != nil {
f.Close()
t.Fatalf("parsing %s gosymtab: %v", file, err)
}
return f, tab
}
func TestLineFromAline(t *testing.T) {
skipIfNotELF(t)
tab := getTable(t)
if tab.go12line != nil {
// aline's don't exist in the Go 1.2 table.
t.Skip("not relevant to Go 1.2 symbol table")
}
// Find the sym package
pkg := tab.LookupFunc("debug/gosym.TestLineFromAline").Obj
if pkg == nil {
t.Fatalf("nil pkg")
}
// Walk every absolute line and ensure that we hit every
// source line monotonically
lastline := make(map[string]int)
final := -1
for i := 0; i < 10000; i++ {
path, line := pkg.lineFromAline(i)
// Check for end of object
if path == "" {
if final == -1 {
final = i - 1
}
continue
} else if final != -1 {
t.Fatalf("reached end of package at absolute line %d, but absolute line %d mapped to %s:%d", final, i, path, line)
}
// It's okay to see files multiple times (e.g., sys.a)
if line == 1 {
lastline[path] = 1
continue
}
// Check that the is the next line in path
ll, ok := lastline[path]
if !ok {
t.Errorf("file %s starts on line %d", path, line)
} else if line != ll+1 {
t.Fatalf("expected next line of file %s to be %d, got %d", path, ll+1, line)
}
lastline[path] = line
}
if final == -1 {
t.Errorf("never reached end of object")
}
}
func TestLineAline(t *testing.T) {
skipIfNotELF(t)
tab := getTable(t)
if tab.go12line != nil {
// aline's don't exist in the Go 1.2 table.
t.Skip("not relevant to Go 1.2 symbol table")
}
for _, o := range tab.Files {
// A source file can appear multiple times in a
// object. alineFromLine will always return alines in
// the first file, so track which lines we've seen.
found := make(map[string]int)
for i := 0; i < 1000; i++ {
path, line := o.lineFromAline(i)
if path == "" {
break
}
// cgo files are full of 'Z' symbols, which we don't handle
if len(path) > 4 && path[len(path)-4:] == ".cgo" {
continue
}
if minline, ok := found[path]; path != "" && ok {
if minline >= line {
// We've already covered this file
continue
}
}
found[path] = line
a, err := o.alineFromLine(path, line)
if err != nil {
t.Errorf("absolute line %d in object %s maps to %s:%d, but mapping that back gives error %s", i, o.Paths[0].Name, path, line, err)
} else if a != i {
t.Errorf("absolute line %d in object %s maps to %s:%d, which maps back to absolute line %d\n", i, o.Paths[0].Name, path, line, a)
}
}
}
}
func TestPCLine(t *testing.T) {
dotest(t)
defer endtest()
f, tab := crack(pclinetestBinary, t)
defer f.Close()
text := f.Section(".text")
textdat, err := text.Data()
if err != nil {
t.Fatalf("reading .text: %v", err)
}
// Test PCToLine
sym := tab.LookupFunc("main.linefrompc")
wantLine := 0
for pc := sym.Entry; pc < sym.End; pc++ {
off := pc - text.Addr // TODO(rsc): should not need off; bug in 8g
if textdat[off] == 255 {
break
}
wantLine += int(textdat[off])
t.Logf("off is %d %#x (max %d)", off, textdat[off], sym.End-pc)
file, line, fn := tab.PCToLine(pc)
if fn == nil {
t.Errorf("failed to get line of PC %#x", pc)
} else if !strings.HasSuffix(file, "pclinetest.s") || line != wantLine || fn != sym {
t.Errorf("PCToLine(%#x) = %s:%d (%s), want %s:%d (%s)", pc, file, line, fn.Name, "pclinetest.s", wantLine, sym.Name)
}
}
// Test LineToPC
sym = tab.LookupFunc("main.pcfromline")
lookupline := -1
wantLine = 0
off := uint64(0) // TODO(rsc): should not need off; bug in 8g
for pc := sym.Value; pc < sym.End; pc += 2 + uint64(textdat[off]) {
file, line, fn := tab.PCToLine(pc)
off = pc - text.Addr
if textdat[off] == 255 {
break
}
wantLine += int(textdat[off])
if line != wantLine {
t.Errorf("expected line %d at PC %#x in pcfromline, got %d", wantLine, pc, line)
off = pc + 1 - text.Addr
continue
}
if lookupline == -1 {
lookupline = line
}
for ; lookupline <= line; lookupline++ {
pc2, fn2, err := tab.LineToPC(file, lookupline)
if lookupline != line {
// Should be nothing on this line
if err == nil {
t.Errorf("expected no PC at line %d, got %#x (%s)", lookupline, pc2, fn2.Name)
}
} else if err != nil {
t.Errorf("failed to get PC of line %d: %s", lookupline, err)
} else if pc != pc2 {
t.Errorf("expected PC %#x (%s) at line %d, got PC %#x (%s)", pc, fn.Name, line, pc2, fn2.Name)
}
}
off = pc + 1 - text.Addr
}
}
// read115Executable returns a hello world executable compiled by Go 1.15.
//
// The file was compiled in /tmp/hello.go:
//
// package main
//
// func main() {
// println("hello")
// }
func read115Executable(tb testing.TB) []byte {
zippedDat, err := os.ReadFile("testdata/pcln115.gz")
if err != nil {
tb.Fatal(err)
}
var gzReader *gzip.Reader
gzReader, err = gzip.NewReader(bytes.NewBuffer(zippedDat))
if err != nil {
tb.Fatal(err)
}
var dat []byte
dat, err = io.ReadAll(gzReader)
if err != nil {
tb.Fatal(err)
}
return dat
}
// Test that we can parse a pclntab from 1.15.
func Test115PclnParsing(t *testing.T) {
dat := read115Executable(t)
const textStart = 0x1001000
pcln := NewLineTable(dat, textStart)
tab, err := NewTable(nil, pcln)
if err != nil {
t.Fatal(err)
}
var f *Func
var pc uint64
pc, f, err = tab.LineToPC("/tmp/hello.go", 3)
if err != nil {
t.Fatal(err)
}
if pcln.version != ver12 {
t.Fatal("Expected pcln to parse as an older version")
}
if pc != 0x105c280 {
t.Fatalf("expect pc = 0x105c280, got 0x%x", pc)
}
if f.Name != "main.main" {
t.Fatalf("expected to parse name as main.main, got %v", f.Name)
}
}
var (
sinkLineTable *LineTable
sinkTable *Table
)
func Benchmark115(b *testing.B) {
dat := read115Executable(b)
const textStart = 0x1001000
b.Run("NewLineTable", func(b *testing.B) {
b.ReportAllocs()
for i := 0; i < b.N; i++ {
sinkLineTable = NewLineTable(dat, textStart)
}
})
pcln := NewLineTable(dat, textStart)
b.Run("NewTable", func(b *testing.B) {
b.ReportAllocs()
for i := 0; i < b.N; i++ {
var err error
sinkTable, err = NewTable(nil, pcln)
if err != nil {
b.Fatal(err)
}
}
})
tab, err := NewTable(nil, pcln)
if err != nil {
b.Fatal(err)
}
b.Run("LineToPC", func(b *testing.B) {
b.ReportAllocs()
for i := 0; i < b.N; i++ {
var f *Func
var pc uint64
pc, f, err = tab.LineToPC("/tmp/hello.go", 3)
if err != nil {
b.Fatal(err)
}
if pcln.version != ver12 {
b.Fatalf("want version=%d, got %d", ver12, pcln.version)
}
if pc != 0x105c280 {
b.Fatalf("want pc=0x105c280, got 0x%x", pc)
}
if f.Name != "main.main" {
b.Fatalf("want name=main.main, got %q", f.Name)
}
}
})
b.Run("PCToLine", func(b *testing.B) {
b.ReportAllocs()
for i := 0; i < b.N; i++ {
file, line, fn := tab.PCToLine(0x105c280)
if file != "/tmp/hello.go" {
b.Fatalf("want name=/tmp/hello.go, got %q", file)
}
if line != 3 {
b.Fatalf("want line=3, got %d", line)
}
if fn.Name != "main.main" {
b.Fatalf("want name=main.main, got %q", fn.Name)
}
}
})
}