[dev.cc] cmd/new6g, etc: reconvert to add profiling

Converted from rsc.io/c2go rev a9bc7f2.
Adds profiling support.

Change-Id: Ie04f86b71e0713c7294416c77d349e0d93798403
Reviewed-on: https://go-review.googlesource.com/5574
Reviewed-by: Rob Pike <r@golang.org>

src/cmd/internal/gc/lex.go

@@ -72,7 +72,7 @@ const (
 func usage() {
 	fmt.Printf("usage: %cg [options] file.go...\n", Thearch.Thechar)
 	obj.Flagprint(1)
-	os.Exit(2)
+	Exit(2)
 }
 
 func fault(s int) {
@@ -225,6 +225,8 @@ func Main() {
 		obj.Flagcount("largemodel", "generate code that assumes a large memory model", &flag_largemodel)
 	}
 
+	obj.Flagstr("cpuprofile", "file: write cpu profile to file", &cpuprofile)
+	obj.Flagstr("memprofile", "file: write memory profile to file", &memprofile)
 	obj.Flagparse(usage)
 	Ctxt.Debugasm = int32(Debug['S'])
 	Ctxt.Debugvlog = int32(Debug['v'])
@@ -233,6 +235,8 @@ func Main() {
 		usage()
 	}
 
+	startProfile()
+
 	if flag_race != 0 {
 		racepkg = mkpkg(newstrlit("runtime/race"))
 		racepkg.Name = "race"

src/cmd/internal/gc/util.go

@@ -2,6 +2,8 @@ package gc
 
 import (
 	"cmd/internal/obj"
+	"os"
+	"runtime/pprof"
 	"strconv"
 	"strings"
 )
@@ -68,3 +70,45 @@ func stringsCompare(a, b string) int {
 	}
 	return +1
 }
+
+var atExitFuncs []func()
+
+func AtExit(f func()) {
+	atExitFuncs = append(atExitFuncs, f)
+}
+
+func Exit(code int) {
+	for i := len(atExitFuncs) - 1; i >= 0; i-- {
+		f := atExitFuncs[i]
+		atExitFuncs = atExitFuncs[:i]
+		f()
+	}
+	os.Exit(code)
+}
+
+var cpuprofile string
+var memprofile string
+
+func startProfile() {
+	if cpuprofile != "" {
+		f, err := os.Create(cpuprofile)
+		if err != nil {
+			Fatal("%v", err)
+		}
+		if err := pprof.StartCPUProfile(f); err != nil {
+			Fatal("%v", err)
+		}
+		AtExit(pprof.StopCPUProfile)
+	}
+	if memprofile != "" {
+		f, err := os.Create(memprofile)
+		if err != nil {
+			Fatal("%v", err)
+		}
+		AtExit(func() {
+			if err := pprof.WriteHeapProfile(f); err != nil {
+				Fatal("%v", err)
+			}
+		})
+	}
+}

src/cmd/new5g/galign.go

@@ -81,4 +81,5 @@ func main() {
 	gc.Thearch.Regnames = regnames
 
 	gc.Main()
+	gc.Exit(0)
 }

src/cmd/new6g/galign.go

@@ -106,4 +106,5 @@ func main() {
 	gc.Thearch.Regnames = regnames
 
 	gc.Main()
+	gc.Exit(0)
 }

src/cmd/new8g/galign.go

@@ -81,4 +81,5 @@ func main() {
 	gc.Thearch.Regnames = regnames
 
 	gc.Main()
+	gc.Exit(0)
 }

src/cmd/new9g/galign.go

@@ -89,4 +89,5 @@ func main() {
 	gc.Thearch.Regnames = regnames
 
 	gc.Main()
+	gc.Exit(0)
 }