cmd/gc: fix export data for aggressive inlining.

Export data was broken after revision 6b602ab487d6
when -l is specified at least 3 times: it makes the compiler
write out func (*T).Method() declarations in export data, which
is not supported.

Also fix the formatting of recover() in export data. It was
not treated like panic() and was rendered as "<node RECOVER>".

R=golang-dev, lvd, minux.ma, rsc
CC=golang-dev
https://golang.org/cl/7067051

src/cmd/gc/export.c

@@ -106,12 +106,19 @@ reexportdep(Node *n)
 		switch(n->class&~PHEAP) {
 		case PFUNC:
 			// methods will be printed along with their type
+			// nodes for T.Method expressions
 			if(n->left && n->left->op == OTYPE)
 				break;
+			// nodes for method calls.
+			if(!n->type || n->type->thistuple > 0)
+				break;
 			// fallthrough
 		case PEXTERN:
-			if(n->sym && !exportedsym(n->sym))
+			if(n->sym && !exportedsym(n->sym)) {
+				if(debug['E'])
+					print("reexport name %S\n", n->sym);
 				exportlist = list(exportlist, n);
+			}
 		}
 		break;
 
@@ -122,6 +129,8 @@ reexportdep(Node *n)
 			if(isptr[t->etype])
 				t = t->type;
 			if(t && t->sym && t->sym->def && !exportedsym(t->sym)) {
+				if(debug['E'])
+					print("reexport type %S from declaration\n", t->sym);
 				exportlist = list(exportlist, t->sym->def);
 			}
 		}

src/cmd/gc/fmt.c

@@ -228,6 +228,7 @@ goopnames[] =
 	[ORANGE]	= "range",
 	[OREAL]		= "real",
 	[ORECV]		= "<-",
+	[ORECOVER]	= "recover",
 	[ORETURN]	= "return",
 	[ORSH]		= ">>",
 	[OSELECT]	= "select",
@@ -1290,6 +1291,7 @@ exprfmt(Fmt *f, Node *n, int prec)
 	case OMAKE:
 	case ONEW:
 	case OPANIC:
+	case ORECOVER:
 	case OPRINT:
 	case OPRINTN:
 		if(n->left)