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// Copyright 2013 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.
// Incomplete source tree on Android.
//go:build !android
// +build !android
package ssa_test
// This file runs the SSA builder in sanity-checking mode on all
// packages beneath $GOROOT and prints some summary information.
//
// Run with "go test -cpu=8 to" set GOMAXPROCS.
import (
"go/ast"
"go/token"
"runtime"
"testing"
"time"
"golang.org/x/tools/go/ast/inspector"
"golang.org/x/tools/go/packages"
"golang.org/x/tools/go/ssa"
"golang.org/x/tools/go/ssa/ssautil"
"golang.org/x/tools/internal/testenv"
"golang.org/x/tools/internal/typeparams/genericfeatures"
)
func bytesAllocated() uint64 {
runtime.GC()
var stats runtime.MemStats
runtime.ReadMemStats(&stats)
return stats.Alloc
}
func TestStdlib(t *testing.T) {
if testing.Short() {
t.Skip("skipping in short mode; too slow (https://golang.org/issue/14113)")
}
testenv.NeedsTool(t, "go")
// Load, parse and type-check the program.
t0 := time.Now()
alloc0 := bytesAllocated()
cfg := &packages.Config{Mode: packages.LoadSyntax}
pkgs, err := packages.Load(cfg, "std", "cmd")
if err != nil {
t.Fatal(err)
}
var nonGeneric int
for i := 0; i < len(pkgs); i++ {
pkg := pkgs[i]
inspect := inspector.New(pkg.Syntax)
features := genericfeatures.ForPackage(inspect, pkg.TypesInfo)
// Skip standard library packages that use generics. This won't be
// sufficient if any standard library packages start _importing_ packages
// that use generics.
if features != 0 {
t.Logf("skipping package %q which uses generics", pkg.PkgPath)
continue
}
pkgs[nonGeneric] = pkg
nonGeneric++
}
pkgs = pkgs[:nonGeneric]
t1 := time.Now()
alloc1 := bytesAllocated()
// Create SSA packages.
var mode ssa.BuilderMode
// Comment out these lines during benchmarking. Approx SSA build costs are noted.
mode |= ssa.SanityCheckFunctions // + 2% space, + 4% time
mode |= ssa.GlobalDebug // +30% space, +18% time
prog, _ := ssautil.Packages(pkgs, mode)
t2 := time.Now()
// Build SSA.
prog.Build()
t3 := time.Now()
alloc3 := bytesAllocated()
numPkgs := len(prog.AllPackages())
if want := 140; numPkgs < want {
t.Errorf("Loaded only %d packages, want at least %d", numPkgs, want)
}
// Keep pkgs reachable until after we've measured memory usage.
if len(pkgs) == 0 {
panic("unreachable")
}
allFuncs := ssautil.AllFunctions(prog)
// Check that all non-synthetic functions have distinct names.
// Synthetic wrappers for exported methods should be distinct too,
// except for unexported ones (explained at (*Function).RelString).
byName := make(map[string]*ssa.Function)
for fn := range allFuncs {
if fn.Synthetic == "" || ast.IsExported(fn.Name()) {
str := fn.String()
prev := byName[str]
byName[str] = fn
if prev != nil {
t.Errorf("%s: duplicate function named %s",
prog.Fset.Position(fn.Pos()), str)
t.Errorf("%s: (previously defined here)",
prog.Fset.Position(prev.Pos()))
}
}
}
// Dump some statistics.
var numInstrs int
for fn := range allFuncs {
for _, b := range fn.Blocks {
numInstrs += len(b.Instrs)
}
}
// determine line count
var lineCount int
prog.Fset.Iterate(func(f *token.File) bool {
lineCount += f.LineCount()
return true
})
// NB: when benchmarking, don't forget to clear the debug +
// sanity builder flags for better performance.
t.Log("GOMAXPROCS: ", runtime.GOMAXPROCS(0))
t.Log("#Source lines: ", lineCount)
t.Log("Load/parse/typecheck: ", t1.Sub(t0))
t.Log("SSA create: ", t2.Sub(t1))
t.Log("SSA build: ", t3.Sub(t2))
// SSA stats:
t.Log("#Packages: ", numPkgs)
t.Log("#Functions: ", len(allFuncs))
t.Log("#Instructions: ", numInstrs)
t.Log("#MB AST+types: ", int64(alloc1-alloc0)/1e6)
t.Log("#MB SSA: ", int64(alloc3-alloc1)/1e6)
}
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