Bug 701239 - add back arg/local-handling in DecompileDestructuringLHS (r=waldo)

--HG--
extra : rebase_source : b296a3a47e4b687f773f9f5cf8bada7812ba2b81

js/src/jit-test/tests/basic/testBug701239.js

@@ -0,0 +1 @@
+(function f(w) { for([w] in 1) {} }).toString();

js/src/jsopcode.cpp

@@ -1679,9 +1679,13 @@ DecompileDestructuringLHS(SprintStack *ss, jsbytecode *pc, jsbytecode *endpc,
       case JSOP_SETLOCAL:
         LOCAL_ASSERT(pc[oplen] == JSOP_POP || pc[oplen] == JSOP_POPN);
         /* FALL THROUGH */
-
       case JSOP_SETLOCALPOP:
-        if (IsVarSlot(jp, pc, &i)) {
+        if (op == JSOP_SETARG) {
+            atom = GetArgOrVarAtom(jp, GET_SLOTNO(pc));
+            LOCAL_ASSERT(atom);
+            if (!QuoteString(&ss->sprinter, atom, 0))
+                return NULL;
+        } else if (IsVarSlot(jp, pc, &i)) {
             atom = GetArgOrVarAtom(jp, i);
             LOCAL_ASSERT(atom);
             if (!QuoteString(&ss->sprinter, atom, 0))
@@ -1691,6 +1695,15 @@ DecompileDestructuringLHS(SprintStack *ss, jsbytecode *pc, jsbytecode *endpc,
             if (!lval || SprintCString(&ss->sprinter, lval) < 0)
                 return NULL;
         }
+        if (op != JSOP_SETLOCALPOP) {
+            pc += oplen;
+            if (pc == endpc)
+                return pc;
+            LOAD_OP_DATA(pc);
+            if (op == JSOP_POPN)
+                return pc;
+            LOCAL_ASSERT(op == JSOP_POP);
+        }
         break;
 
       default: {