cmd/compile: avoid unnecessary interface conversion in bloop

Fixes #76482

Change-Id: I076568d8ae92ad6c9e0a5797cfe5bbfb615f63d2
Reviewed-on: https://go-review.googlesource.com/c/go/+/725180
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Cuong Manh Le <cuong.manhle.vn@gmail.com>

Author: cuonglm

src/cmd/compile/internal/bloop/bloop.go

@@ -74,7 +74,7 @@ func getNameFromNode(n ir.Node) *ir.Name {
 }
 
 // keepAliveAt returns a statement that is either curNode, or a
-// block containing curNode followed by a call to runtime.keepAlive for each
+// block containing curNode followed by a call to runtime.KeepAlive for each
 // node in ns. These calls ensure that nodes in ns will be live until
 // after curNode's execution.
 func keepAliveAt(ns []ir.Node, curNode ir.Node) ir.Node {
@@ -94,7 +94,7 @@ func keepAliveAt(ns []ir.Node, curNode ir.Node) ir.Node {
 		if n.Sym().IsBlank() {
 			continue
 		}
-		arg := ir.NewConvExpr(pos, ir.OCONV, types.Types[types.TINTER], n)
+		arg := ir.NewConvExpr(pos, ir.OCONV, types.Types[types.TUNSAFEPTR], typecheck.NodAddr(n))
 		if !n.Type().IsInterface() {
 			srcRType0 := reflectdata.TypePtrAt(pos, n.Type())
 			arg.TypeWord = srcRType0

test/bloop.go

@@ -31,23 +31,23 @@ func test(b *testing.B, localsink, cond int) { // ERROR ".*"
 	}
 	somethingptr := &something
 	for b.Loop() { // ERROR "inlining call to testing\.\(\*B\)\.Loop"
-		caninline(1)                 // ERROR "inlining call to caninline" "function result will be kept alive" ".* does not escape"
-		caninlineNoRet(1)            // ERROR "inlining call to caninlineNoRet" "function arg will be kept alive" ".* does not escape"
+		caninline(1)                 // ERROR "inlining call to caninline" "function result will be kept alive"
+		caninlineNoRet(1)            // ERROR "inlining call to caninlineNoRet" "function arg will be kept alive"
 		caninlineVariadic(1)         // ERROR "inlining call to caninlineVariadic" "function arg will be kept alive" ".* does not escape"
 		caninlineVariadic(localsink) // ERROR "inlining call to caninlineVariadic" "localsink will be kept alive" ".* does not escape"
-		localsink = caninline(1)     // ERROR "inlining call to caninline" "localsink will be kept alive" ".* does not escape"
-		localsink += 5               // ERROR "localsink will be kept alive" ".* does not escape"
-		localsink, cond = 1, 2       // ERROR "localsink will be kept alive" "cond will be kept alive" ".* does not escape"
+		localsink = caninline(1)     // ERROR "inlining call to caninline" "localsink will be kept alive"
+		localsink += 5               // ERROR "localsink will be kept alive"
+		localsink, cond = 1, 2       // ERROR "localsink will be kept alive" "cond will be kept alive"
 		*somethingptr = 1            // ERROR "dereference will be kept alive"
 		if cond > 0 {
-			caninline(1) // ERROR "inlining call to caninline" "function result will be kept alive" ".* does not escape"
+			caninline(1) // ERROR "inlining call to caninline" "function result will be kept alive"
 		}
 		switch cond {
 		case 2:
-			caninline(1) // ERROR "inlining call to caninline" "function result will be kept alive" ".* does not escape"
+			caninline(1) // ERROR "inlining call to caninline" "function result will be kept alive"
 		}
 		{
-			caninline(1) // ERROR "inlining call to caninline" "function result will be kept alive" ".* does not escape"
+			caninline(1) // ERROR "inlining call to caninline" "function result will be kept alive"
 		}
 	}
 }