1// Copyright 2013 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5// Incomplete source tree on Android.
6
7// +build !android
8
9package ssa_test
10
11// This file runs the SSA builder in sanity-checking mode on all
12// packages beneath $GOROOT and prints some summary information.
13//
14// Run with "go test -cpu=8 to" set GOMAXPROCS.
15
16import (
17	"go/ast"
18	"go/build"
19	"go/token"
20	"runtime"
21	"testing"
22	"time"
23
24	"golang.org/x/tools/go/buildutil"
25	"golang.org/x/tools/go/loader"
26	"golang.org/x/tools/go/ssa"
27	"golang.org/x/tools/go/ssa/ssautil"
28	"golang.org/x/tools/internal/testenv"
29)
30
31func bytesAllocated() uint64 {
32	runtime.GC()
33	var stats runtime.MemStats
34	runtime.ReadMemStats(&stats)
35	return stats.Alloc
36}
37
38func TestStdlib(t *testing.T) {
39	if testing.Short() {
40		t.Skip("skipping in short mode; too slow (https://golang.org/issue/14113)")
41	}
42	testenv.NeedsTool(t, "go")
43
44	// Load, parse and type-check the program.
45	t0 := time.Now()
46	alloc0 := bytesAllocated()
47
48	// Load, parse and type-check the program.
49	ctxt := build.Default // copy
50	ctxt.GOPATH = ""      // disable GOPATH
51	conf := loader.Config{Build: &ctxt}
52	for _, path := range buildutil.AllPackages(conf.Build) {
53		conf.ImportWithTests(path)
54	}
55
56	iprog, err := conf.Load()
57	if err != nil {
58		t.Fatalf("Load failed: %v", err)
59	}
60
61	t1 := time.Now()
62	alloc1 := bytesAllocated()
63
64	// Create SSA packages.
65	var mode ssa.BuilderMode
66	// Comment out these lines during benchmarking.  Approx SSA build costs are noted.
67	mode |= ssa.SanityCheckFunctions // + 2% space, + 4% time
68	mode |= ssa.GlobalDebug          // +30% space, +18% time
69	prog := ssautil.CreateProgram(iprog, mode)
70
71	t2 := time.Now()
72
73	// Build SSA.
74	prog.Build()
75
76	t3 := time.Now()
77	alloc3 := bytesAllocated()
78
79	numPkgs := len(prog.AllPackages())
80	if want := 140; numPkgs < want {
81		t.Errorf("Loaded only %d packages, want at least %d", numPkgs, want)
82	}
83
84	// Keep iprog reachable until after we've measured memory usage.
85	if len(iprog.AllPackages) == 0 {
86		panic("unreachable")
87	}
88
89	allFuncs := ssautil.AllFunctions(prog)
90
91	// Check that all non-synthetic functions have distinct names.
92	// Synthetic wrappers for exported methods should be distinct too,
93	// except for unexported ones (explained at (*Function).RelString).
94	byName := make(map[string]*ssa.Function)
95	for fn := range allFuncs {
96		if fn.Synthetic == "" || ast.IsExported(fn.Name()) {
97			str := fn.String()
98			prev := byName[str]
99			byName[str] = fn
100			if prev != nil {
101				t.Errorf("%s: duplicate function named %s",
102					prog.Fset.Position(fn.Pos()), str)
103				t.Errorf("%s:   (previously defined here)",
104					prog.Fset.Position(prev.Pos()))
105			}
106		}
107	}
108
109	// Dump some statistics.
110	var numInstrs int
111	for fn := range allFuncs {
112		for _, b := range fn.Blocks {
113			numInstrs += len(b.Instrs)
114		}
115	}
116
117	// determine line count
118	var lineCount int
119	prog.Fset.Iterate(func(f *token.File) bool {
120		lineCount += f.LineCount()
121		return true
122	})
123
124	// NB: when benchmarking, don't forget to clear the debug +
125	// sanity builder flags for better performance.
126
127	t.Log("GOMAXPROCS:           ", runtime.GOMAXPROCS(0))
128	t.Log("#Source lines:        ", lineCount)
129	t.Log("Load/parse/typecheck: ", t1.Sub(t0))
130	t.Log("SSA create:           ", t2.Sub(t1))
131	t.Log("SSA build:            ", t3.Sub(t2))
132
133	// SSA stats:
134	t.Log("#Packages:            ", numPkgs)
135	t.Log("#Functions:           ", len(allFuncs))
136	t.Log("#Instructions:        ", numInstrs)
137	t.Log("#MB AST+types:        ", int64(alloc1-alloc0)/1e6)
138	t.Log("#MB SSA:              ", int64(alloc3-alloc1)/1e6)
139}
140