diff --git a/src/cmd/compile/internal/gc/ssa.go b/src/cmd/compile/internal/gc/ssa.go
index 7c74054b60..d53bd1aa4f 100644
--- a/src/cmd/compile/internal/gc/ssa.go
+++ b/src/cmd/compile/internal/gc/ssa.go
@@ -2103,6 +2103,9 @@ func (s *state) expr(n ir.Node) *ssa.Value {
 		// Assume everything will work out, so set up our return value.
 		// Anything interesting that happens from here is a fatal.
 		x := s.expr(n.Left())
+		if to == from {
+			return x
+		}
 
 		// Special case for not confusing GC and liveness.
 		// We don't want pointers accidentally classified
@@ -2966,6 +2969,10 @@ func (s *state) condBranch(cond ir.Node, yes, no *ssa.Block, likely int8) {
 		s.stmtList(cond.Init())
 		s.condBranch(cond.Left(), no, yes, -likely)
 		return
+	case ir.OCONVNOP:
+		s.stmtList(cond.Init())
+		s.condBranch(cond.Left(), yes, no, likely)
+		return
 	}
 	c := s.expr(cond)
 	b := s.endBlock()
@@ -4903,6 +4910,9 @@ func (s *state) addr(n ir.Node) *ssa.Value {
 		return s.newValue1I(ssa.OpOffPtr, t, n.Offset(),
 			s.entryNewValue0(ssa.OpGetClosurePtr, s.f.Config.Types.BytePtr))
 	case ir.OCONVNOP:
+		if n.Type() == n.Left().Type() {
+			return s.addr(n.Left())
+		}
 		addr := s.addr(n.Left())
 		return s.newValue1(ssa.OpCopy, t, addr) // ensure that addr has the right type
 	case ir.OCALLFUNC, ir.OCALLINTER, ir.OCALLMETH:
diff --git a/src/cmd/compile/internal/gc/walk.go b/src/cmd/compile/internal/gc/walk.go
index f439237936..c0f447f1a2 100644
--- a/src/cmd/compile/internal/gc/walk.go
+++ b/src/cmd/compile/internal/gc/walk.go
@@ -966,6 +966,9 @@ opswitch:
 
 	case ir.OCONV, ir.OCONVNOP:
 		n.SetLeft(walkexpr(n.Left(), init))
+		if n.Op() == ir.OCONVNOP && n.Type() == n.Left().Type() {
+			return n.Left()
+		}
 		if n.Op() == ir.OCONVNOP && checkPtr(Curfn, 1) {
 			if n.Type().IsPtr() && n.Left().Type().IsUnsafePtr() { // unsafe.Pointer to *T
 				n = walkCheckPtrAlignment(n, init, nil)