github.com/FenixAra/go@v0.0.0-20170127160404-96ea0918e670/src/cmd/compile/internal/gc/util.go (about)

     1  // Copyright 2015 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  package gc
     6  
     7  import (
     8  	"os"
     9  	"runtime"
    10  	"runtime/pprof"
    11  )
    12  
    13  func (n *Node) Line() string {
    14  	return Ctxt.LineHist.LineString(int(n.Lineno))
    15  }
    16  
    17  var atExitFuncs []func()
    18  
    19  func atExit(f func()) {
    20  	atExitFuncs = append(atExitFuncs, f)
    21  }
    22  
    23  func Exit(code int) {
    24  	for i := len(atExitFuncs) - 1; i >= 0; i-- {
    25  		f := atExitFuncs[i]
    26  		atExitFuncs = atExitFuncs[:i]
    27  		f()
    28  	}
    29  	os.Exit(code)
    30  }
    31  
    32  var (
    33  	cpuprofile     string
    34  	memprofile     string
    35  	memprofilerate int64
    36  	traceprofile   string
    37  	traceHandler   func(string)
    38  )
    39  
    40  func startProfile() {
    41  	if cpuprofile != "" {
    42  		f, err := os.Create(cpuprofile)
    43  		if err != nil {
    44  			Fatalf("%v", err)
    45  		}
    46  		if err := pprof.StartCPUProfile(f); err != nil {
    47  			Fatalf("%v", err)
    48  		}
    49  		atExit(pprof.StopCPUProfile)
    50  	}
    51  	if memprofile != "" {
    52  		if memprofilerate != 0 {
    53  			runtime.MemProfileRate = int(memprofilerate)
    54  		}
    55  		f, err := os.Create(memprofile)
    56  		if err != nil {
    57  			Fatalf("%v", err)
    58  		}
    59  		atExit(func() {
    60  			// Profile all outstanding allocations.
    61  			runtime.GC()
    62  			// compilebench parses the memory profile to extract memstats,
    63  			// which are only written in the legacy pprof format.
    64  			// See golang.org/issue/18641 and runtime/pprof/pprof.go:writeHeap.
    65  			const writeLegacyFormat = 1
    66  			if err := pprof.Lookup("heap").WriteTo(f, writeLegacyFormat); err != nil {
    67  				Fatalf("%v", err)
    68  			}
    69  		})
    70  	}
    71  	if traceprofile != "" && traceHandler != nil {
    72  		traceHandler(traceprofile)
    73  	}
    74  }