cmd/compile: set types properly for imported funcs with closures

For the new export/import of node types, we were just missing setting
the types of the closure variables (which have the same types as the
captured variables) and the OCLOSURE node itself (which has the same
type as the Func node).

Re-enabled inlining of functions with closures.

Change-Id: I687149b061f3ffeec3244ff02dc6e946659077a9
Reviewed-on: https://go-review.googlesource.com/c/go/+/308974
Trust: Dan Scales <danscales@google.com>
Run-TryBot: Dan Scales <danscales@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

src/cmd/compile/internal/inline/inl.go

@@ -354,7 +354,7 @@ func (v *hairyVisitor) doNode(n ir.Node) bool {
 		return true
 
 	case ir.OCLOSURE:
-		if base.Debug.InlFuncsWithClosures == 0 || typecheck.Go117ExportTypes { // TODO: remove latter condition
+		if base.Debug.InlFuncsWithClosures == 0 {
 			v.reason = "not inlining functions with closures"
 			return true
 		}

src/cmd/compile/internal/typecheck/iimport.go

@@ -1112,6 +1112,14 @@ func (r *importReader) node() ir.Node {
 		cvars := make([]*ir.Name, r.int64())
 		for i := range cvars {
 			cvars[i] = ir.CaptureName(r.pos(), fn, r.localName().Canonical())
+			if go117ExportTypes {
+				if cvars[i].Type() != nil || cvars[i].Defn == nil {
+					base.Fatalf("bad import of closure variable")
+				}
+				// Closure variable should have Defn set, which is its captured
+				// variable, and it gets the same type as the captured variable.
+				cvars[i].SetType(cvars[i].Defn.Type())
+			}
 		}
 		fn.ClosureVars = cvars
 		r.allClosureVars = append(r.allClosureVars, cvars...)
@@ -1133,6 +1141,9 @@ func (r *importReader) node() ir.Node {
 
 		clo := ir.NewClosureExpr(pos, fn)
 		fn.OClosure = clo
+		if go117ExportTypes {
+			clo.SetType(typ)
+		}
 
 		return clo
 

test/closure3.dir/main.go

@@ -93,11 +93,11 @@ func main() {
 		y := func(x int) int { // ERROR "can inline main.func11" "func literal does not escape"
 			return x + 2
 		}
-		y, sink = func() (func(int) int, int) { // ERROR "func literal does not escape"
+		y, sink = func() (func(int) int, int) { // ERROR "can inline main.func12"
-			return func(x int) int { // ERROR "can inline main.func12" "func literal escapes"
+			return func(x int) int { // ERROR "can inline main.func12"
 				return x + 1
 			}, 42
-		}()
+		}() // ERROR "func literal does not escape" "inlining call to main.func12"
 		if y(40) != 41 {
 			ppanic("y(40) != 41")
 		}
@@ -105,14 +105,14 @@ func main() {
 
 	{
 		func() { // ERROR "func literal does not escape"
-			y := func(x int) int { // ERROR "can inline main.func13.1" "func literal does not escape"
+			y := func(x int) int { // ERROR "func literal does not escape" "can inline main.func13.1"
 				return x + 2
 			}
-			y, sink = func() (func(int) int, int) { // ERROR "func literal does not escape"
+			y, sink = func() (func(int) int, int) { // ERROR "can inline main.func13.2"
-				return func(x int) int { // ERROR "can inline main.func13.2" "func literal escapes"
+				return func(x int) int { // ERROR "can inline main.func13.2"
 					return x + 1
 				}, 42
-			}()
+			}() // ERROR "inlining call to main.func13.2" "func literal does not escape"
 			if y(40) != 41 {
 				ppanic("y(40) != 41")
 			}
@@ -187,29 +187,29 @@ func main() {
 
 	{
 		x := 42
-		if z := func(y int) int { // ERROR "func literal does not escape"
+		if z := func(y int) int { // ERROR "can inline main.func22"
-			return func() int { // ERROR "can inline main.func22.1"
+			return func() int { // ERROR "can inline main.func22.1" "can inline main.func30"
 				return x + y
 			}() // ERROR "inlining call to main.func22.1"
-		}(1); z != 43 {
+		}(1); z != 43 { // ERROR "inlining call to main.func22" "inlining call to main.func30"
 			ppanic("z != 43")
 		}
-		if z := func(y int) int { // ERROR "func literal does not escape"
+		if z := func(y int) int { // ERROR "func literal does not escape" "can inline main.func23"
-			return func() int { // ERROR "can inline main.func23.1"
+			return func() int { // ERROR "can inline main.func23.1" "can inline main.func31"
 				return x + y
 			}() // ERROR "inlining call to main.func23.1"
-		}; z(1) != 43 {
+		}; z(1) != 43 { // ERROR "inlining call to main.func23" "inlining call to main.func31"
 			ppanic("z(1) != 43")
 		}
 	}
 
 	{
 		a := 1
-		func() { // ERROR "func literal does not escape"
+		func() { // ERROR "can inline main.func24"
-			func() { // ERROR "can inline main.func24"
+			func() { // ERROR "can inline main.func24" "can inline main.func32"
 				a = 2
 			}() // ERROR "inlining call to main.func24"
-		}()
+		}() // ERROR "inlining call to main.func24" "inlining call to main.func32"
 		if a != 2 {
 			ppanic("a != 2")
 		}
@@ -250,12 +250,12 @@ func main() {
 		a := 2
 		if r := func(x int) int { // ERROR "func literal does not escape"
 			b := 3
-			return func(y int) int { // ERROR "func literal does not escape"
+			return func(y int) int { // ERROR "can inline main.func27.1"
 				c := 5
-				return func(z int) int { // ERROR "can inline main.func27.1.1"
+				return func(z int) int { // ERROR "can inline main.func27.1.1" "can inline main.func27.2"
 					return a*x + b*y + c*z
 				}(10) // ERROR "inlining call to main.func27.1.1"
-			}(100)
+			}(100) // ERROR "inlining call to main.func27.1" "inlining call to main.func27.2"
 		}(1000); r != 2350 {
 			ppanic("r != 2350")
 		}
@@ -265,15 +265,15 @@ func main() {
 		a := 2
 		if r := func(x int) int { // ERROR "func literal does not escape"
 			b := 3
-			return func(y int) int { // ERROR "func literal does not escape"
+			return func(y int) int { // ERROR "can inline main.func28.1"
 				c := 5
-				func(z int) { // ERROR "can inline main.func28.1.1"
+				func(z int) { // ERROR "can inline main.func28.1.1" "can inline main.func28.2"
 					a = a * x
 					b = b * y
 					c = c * z
 				}(10) // ERROR "inlining call to main.func28.1.1"
 				return a + c
-			}(100) + b
+			}(100) + b // ERROR "inlining call to main.func28.1" "inlining call to main.func28.2"
 		}(1000); r != 2350 {
 			ppanic("r != 2350")
 		}

test/inline.go

@@ -58,7 +58,7 @@ func _() int { // ERROR "can inline _"
 var somethingWrong error
 
 // local closures can be inlined
-func l(x, y int) (int, int, error) {
+func l(x, y int) (int, int, error) { // ERROR "can inline l"
 	e := func(err error) (int, int, error) { // ERROR "can inline l.func1" "func literal does not escape" "leaking param: err to result"
 		return 0, 0, err
 	}
@@ -90,19 +90,19 @@ func n() int {
 // make sure assignment inside closure is detected
 func o() int {
 	foo := func() int { return 1 } // ERROR "can inline o.func1" "func literal does not escape"
-	func(x int) {                  // ERROR "func literal does not escape"
+	func(x int) {                  // ERROR "can inline o.func2"
 		if x > 10 {
-			foo = func() int { return 2 } // ERROR "can inline o.func2" "func literal escapes"
+			foo = func() int { return 2 } // ERROR "can inline o.func2"
 		}
-	}(11)
+	}(11) // ERROR "func literal does not escape" "inlining call to o.func2"
 	return foo()
 }
 
-func p() int {
+func p() int { // ERROR "can inline p"
 	return func() int { return 42 }() // ERROR "can inline p.func1" "inlining call to p.func1"
 }
 
-func q(x int) int {
+func q(x int) int { // ERROR "can inline q"
 	foo := func() int { return x * 2 } // ERROR "can inline q.func1" "func literal does not escape"
 	return foo()                       // ERROR "inlining call to q.func1"
 }
@@ -111,15 +111,15 @@ func r(z int) int {
 	foo := func(x int) int { // ERROR "can inline r.func1" "func literal does not escape"
 		return x + z
 	}
-	bar := func(x int) int { // ERROR "func literal does not escape"
+	bar := func(x int) int { // ERROR "func literal does not escape" "can inline r.func2"
-		return x + func(y int) int { // ERROR "can inline r.func2.1"
+		return x + func(y int) int { // ERROR "can inline r.func2.1" "can inline r.func3"
 			return 2*y + x*z
 		}(x) // ERROR "inlining call to r.func2.1"
 	}
-	return foo(42) + bar(42) // ERROR "inlining call to r.func1"
+	return foo(42) + bar(42) // ERROR "inlining call to r.func1" "inlining call to r.func2" "inlining call to r.func3"
 }
 
-func s0(x int) int {
+func s0(x int) int { // ERROR "can inline s0"
 	foo := func() { // ERROR "can inline s0.func1" "func literal does not escape"
 		x = x + 1
 	}
@@ -127,7 +127,7 @@ func s0(x int) int {
 	return x
 }
 
-func s1(x int) int {
+func s1(x int) int { // ERROR "can inline s1"
 	foo := func() int { // ERROR "can inline s1.func1" "func literal does not escape"
 		return x
 	}