go.tools/go/ssa: name anon funcs by their enclosing func.

Before, they were named func@line:col which made them easy to find in the source if you know the file, but hard if you don't, and it made tests fragile.

Now, they are named outer$1, outer$2, etc, which makes them
more informative in a UI since "outer" has meaning.

LGTM=crawshaw
R=crawshaw
CC=golang-codereviews
https://golang.org/cl/65630048

go/loader/source_test.go

@@ -60,11 +60,11 @@ func TestEnclosingFunction(t *testing.T) {
 		// Function literal:
 		{`package main
 		  func f() { println(func() { print(300) }) }`,
-			"300", "func@2.24"},
+			"300", "f$1"},
 		// Doubly nested
 		{`package main
 		  func f() { println(func() { print(func() { print(350) })})}`,
-			"350", "func@2.39"},
+			"350", "f$1$1"},
 		// Implicit init for package-level var initializer.
 		{"package main; var a = 400", "400", "main.init"},
 		// No code for constants:
@@ -79,7 +79,7 @@ func TestEnclosingFunction(t *testing.T) {
 		// init() containing FuncLit.
 		{`package main
 		  func init() { println(func(){print(900)}) }`,
-			"900", "func@2.27"},
+			"900", "init$1$1"},
 	}
 	for _, test := range tests {
 		conf := loader.Config{Fset: token.NewFileSet()}

go/pointer/testdata/channels.go

@@ -19,7 +19,7 @@ func chan1() {
 	print(<-chA) // @pointsto main.incr
 
 	print(chB)   // @pointsto makechan@c1makeB:13
-	print(<-chB) // @pointsto main.decr | func@16.9
+	print(<-chB) // @pointsto main.decr | chan1$1
 }
 
 func chan2() {
@@ -40,10 +40,10 @@ func chan2() {
 	print(<-chA) // @pointsto main.incr
 
 	print(chB)   // @pointsto makechan@c2makeB:13
-	print(<-chB) // @pointsto main.decr | func@30.9
+	print(<-chB) // @pointsto main.decr | chan2$1
 
 	print(chAB)   // @pointsto makechan@c2makeA:13 | makechan@c2makeB:13
-	print(<-chAB) // @pointsto main.incr | main.decr | func@30.9
+	print(<-chAB) // @pointsto main.incr | main.decr | chan2$1
 
 	(<-chA)(3)
 }
@@ -59,7 +59,7 @@ func chan3() {
 	print(chA)   // @pointsto makechan@c3makeA:13
 	print(<-chA) // @pointsto main.incr
 	print(chB)   // @pointsto makechan@c3makeB:13
-	print(<-chB) // @pointsto main.decr | func@58.9
+	print(<-chB) // @pointsto main.decr | chan3$1
 
 	(<-chA)(3)
 }

go/pointer/testdata/func.go

@@ -28,9 +28,9 @@ func func1() {
 	print(&a)    // @pointsto main.a
 }
 
-// @calls main.func1 -> func@19.7
+// @calls main.func1 -> func1$2
-// @calls main.func1 -> func@11.7
+// @calls main.func1 -> func1$1
-// @calls func@19.7 ->  func@11.7
+// @calls func1$2 ->  func1$1
 
 func func2() {
 	var x, y *int
@@ -124,7 +124,7 @@ func func6() {
 	print(f()) // @pointsto main.a
 }
 
-// @calls main.func6 -> func@121.7
+// @calls main.func6 -> func6$1
 
 type I interface {
 	f()

go/ssa/builder.go

@@ -468,9 +468,8 @@ func (b *builder) expr0(fn *Function, e ast.Expr) Value {
 		panic("non-constant BasicLit") // unreachable
 
 	case *ast.FuncLit:
-		posn := fn.Prog.Fset.Position(e.Type.Func)
 		fn2 := &Function{
-			name:      fmt.Sprintf("func@%d.%d", posn.Line, posn.Column),
+			name:      fmt.Sprintf("%s$%d", fn.Name(), 1+len(fn.AnonFuncs)),
 			Signature: fn.Pkg.typeOf(e.Type).Underlying().(*types.Signature),
 			pos:       e.Type.Func,
 			Enclosing: fn,

go/ssa/func.go

@@ -457,7 +457,9 @@ func (f *Function) emit(instr Instruction) Value {
 //      "(*sync.WaitGroup).Add"     // a declared method
 //      "(*Return).Block"           // a promotion wrapper method (intra-package ref)
 //      "(Instruction).Block"       // an interface method wrapper (intra-package ref)
-//      "func@5.32"                 // an anonymous function
+//      "main$1"                    // an anonymous function
+//      "init$1"                    // a declared init function
+//      "init"                      // the synthesized package initializer
 //      "bound$(*T).f"              // a bound method wrapper
 //
 // If from==f.Pkg, suppress package qualification.

go/ssa/interp/testdata/callstack.go

@@ -15,7 +15,7 @@ func f() {
 	for _, f := range pc {
 		Func := runtime.FuncForPC(f)
 		name := Func.Name()
-		if strings.Contains(name, "func") {
+		if strings.Contains(name, "$") || strings.Contains(name, ".func") {
 			name = "func" // anon funcs vary across toolchains
 		}
 		file, line := Func.FileLine(0)

oracle/testdata/src/main/callgraph-json.golden

@@ -43,7 +43,7 @@
 			"pos": "testdata/src/main/callgraph-json.go:9:6"
 		},
 		{
-			"name": "func@31.8",
+			"name": "main$1",
 			"pos": "testdata/src/main/callgraph-json.go:31:8"
 		}
 	]

oracle/testdata/src/main/callgraph.golden

@@ -11,7 +11,7 @@ Non-numbered nodes indicate back- or cross-edges to the node whose
 3	        A
 4	        B
 5	    call2
-6	        func@33.8
+6	        main$1
 7	    nop
 
 -------- @callgraph callgraph-complete --------
@@ -30,6 +30,6 @@ Non-numbered nodes indicate back- or cross-edges to the node whose
 6	            main.A
 7	            main.B
 8	        main.call2
-9	            func@33.8
+9	            main$1
 10	        main.nop
 

oracle/testdata/src/main/calls-json.golden

@@ -6,7 +6,7 @@
 		"desc": "dynamic function call",
 		"callees": [
 			{
-				"name": "func@12.7",
+				"name": "main$1",
 				"pos": "testdata/src/main/calls-json.go:12:7"
 			}
 		]
@@ -16,7 +16,7 @@
 	"mode": "callstack",
 	"callstack": {
 		"pos": "testdata/src/main/calls-json.go:12:7",
-		"target": "func@12.7",
+		"target": "main$1",
 		"callers": [
 			{
 				"pos": "testdata/src/main/calls-json.go:8:3",

oracle/testdata/src/main/calls.golden

@@ -35,11 +35,11 @@ main.store is called from these 2 sites:
 
 -------- @pointsto pointsto-result-f --------
 this func() *int may point to these objects:
-	func@50.7
+	main$1
 
 -------- @callees callees-main.call-f --------
 this dynamic function call dispatches to:
-	func@50.7
+	main$1
 
 -------- @callers callers-main.call --------
 main.call is called from these 2 sites:

oracle/testdata/src/main/pointsto.golden

@@ -31,7 +31,7 @@ this func() may point to these objects:
 
 -------- @pointsto ref-anon --------
 this func() may point to these objects:
-	func@25.10
+	main$1
 
 -------- @pointsto ref-global --------
 this *string may point to these objects: