github.com/jd-ly/tools@v0.5.7/go/ssa/stdlib_test.go (about)

     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  
     9  package 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  
    16  import (
    17  	"go/ast"
    18  	"go/build"
    19  	"go/token"
    20  	"runtime"
    21  	"testing"
    22  	"time"
    23  
    24  	"github.com/jd-ly/tools/go/buildutil"
    25  	"github.com/jd-ly/tools/go/loader"
    26  	"github.com/jd-ly/tools/go/ssa"
    27  	"github.com/jd-ly/tools/go/ssa/ssautil"
    28  	"github.com/jd-ly/tools/internal/testenv"
    29  )
    30  
    31  func bytesAllocated() uint64 {
    32  	runtime.GC()
    33  	var stats runtime.MemStats
    34  	runtime.ReadMemStats(&stats)
    35  	return stats.Alloc
    36  }
    37  
    38  func 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  }