Populate more carefully the profile.proto in the topproto output

Instead of putting a pretty-printed string on the function.name,
populate the function.name, .file and location line with the
information from the node. This will help more easily extract this
information.

Also add some cachign to reuse functions and added a small test.

internal/report/report.go

@@ -286,20 +286,16 @@ func printTopProto(w io.Writer, rpt *Report) error {
 		PeriodType:    p.PeriodType,
 		Period:        p.Period,
 	}
-	var flatSum int64
+	functionMap := make(functionMap)
 	for i, n := range g.Nodes {
-		name, flat, cum := n.Info.PrintableName(), n.FlatValue(), n.CumValue()
-
-		flatSum += flat
-		f := &profile.Function{
-			ID:         uint64(i + 1),
-			Name:       name,
-			SystemName: name,
-		}
+		f := functionMap.FindOrAdd(n.Info)
+		flat, cum := n.FlatValue(), n.CumValue()
 		l := &profile.Location{
-			ID: uint64(i + 1),
+			ID:      uint64(i + 1),
+			Address: n.Info.Address,
 			Line: []profile.Line{
 				{
+					Line:     int64(n.Info.Lineno),
 					Function: f,
 				},
 			},
@@ -319,6 +315,26 @@ func printTopProto(w io.Writer, rpt *Report) error {
 	return out.Write(w)
 }
 
+type functionMap map[string]*profile.Function
+
+func (fm functionMap) FindOrAdd(ni graph.NodeInfo) *profile.Function {
+	fName := fmt.Sprintf("%q%q%q%d", ni.Name, ni.OrigName, ni.File, ni.StartLine)
+
+	if f := fm[fName]; f != nil {
+		return f
+	}
+
+	f := &profile.Function{
+		ID:         uint64(len(fm) + 1),
+		Name:       ni.Name,
+		SystemName: ni.OrigName,
+		Filename:   ni.File,
+		StartLine:  int64(ni.StartLine),
+	}
+	fm[fName] = f
+	return f
+}
+
 // printAssembly prints an annotated assembly listing.
 func printAssembly(w io.Writer, rpt *Report, obj plugin.ObjTool) error {
 	o := rpt.options

internal/report/report_test.go

@@ -236,3 +236,27 @@ func TestDisambiguation(t *testing.T) {
 		}
 	}
 }
+
+func TestFunctionMap(t *testing.T) {
+
+	fm := make(functionMap)
+	nodes := []graph.NodeInfo{
+		{Name: "fun1"},
+		{Name: "fun2", File: "filename"},
+		{Name: "fun1"},
+		{Name: "fun2", File: "filename2"},
+	}
+
+	want := []profile.Function{
+		{ID: 1, Name: "fun1"},
+		{ID: 2, Name: "fun2", Filename: "filename"},
+		{ID: 1, Name: "fun1"},
+		{ID: 3, Name: "fun2", Filename: "filename2"},
+	}
+
+	for i, tc := range nodes {
+		if got, want := fm.FindOrAdd(tc), want[i]; *got != want {
+			t.Errorf("%d: want %v, got %v", i, want, got)
+		}
+	}
+}