diff --git a/mozilla/js/src/jsopcode.c b/mozilla/js/src/jsopcode.c
index 953311e4f22..bc46f723111 100644
--- a/mozilla/js/src/jsopcode.c
+++ b/mozilla/js/src/jsopcode.c
@@ -2323,7 +2323,9 @@ Decompile(SprintStack *ss, jsbytecode *pc, intN nb)
                 break;
 
               case JSOP_DELELEM:
+                op = JSOP_NOP;          /* turn off parens */
                 xval = POP_STR();
+                op = saveop;
                 lval = POP_STR();
                 if (*xval == '\0')
                     goto do_delete_lval;
@@ -2395,7 +2397,9 @@ Decompile(SprintStack *ss, jsbytecode *pc, intN nb)
 
               case JSOP_INCELEM:
               case JSOP_DECELEM:
+                op = JSOP_NOP;          /* turn off parens */
                 xval = POP_STR();
+                op = saveop;
                 lval = POP_STR();
                 if (*xval != '\0') {
                     todo = Sprint(&ss->sprinter,
@@ -2454,7 +2458,9 @@ Decompile(SprintStack *ss, jsbytecode *pc, intN nb)
 
               case JSOP_ELEMINC:
               case JSOP_ELEMDEC:
+                op = JSOP_NOP;          /* turn off parens */
                 xval = POP_STR();
+                op = saveop;
                 lval = POP_STR();
                 if (*xval != '\0') {
                     todo = Sprint(&ss->sprinter,
diff --git a/mozilla/js/src/jsopcode.tbl b/mozilla/js/src/jsopcode.tbl
index 2a9d27a6727..356d0919241 100644
--- a/mozilla/js/src/jsopcode.tbl
+++ b/mozilla/js/src/jsopcode.tbl
@@ -309,7 +309,7 @@ OPDEF(JSOP_SETLOCALPOP, 130, "setlocalpop", NULL,     3,  1,  0,  3,  JOF_LOCAL|
 OPDEF(JSOP_GROUP,       131, "group",       NULL,     1,  0,  0,  0,  JOF_BYTE)
 
 /* Host object extension: given 'o.item(i) = j', the left-hand side compiles JSOP_SETCALL, rather than JSOP_CALL. */
-OPDEF(JSOP_SETCALL,     132, "setcall",     NULL,     3, -1,  2,  3,  JOF_UINT16|JOF_SET|JOF_ASSIGNING)
+OPDEF(JSOP_SETCALL,     132, "setcall",     NULL,     3, -1,  2, 17,  JOF_UINT16|JOF_SET|JOF_ASSIGNING)
 
 /*
  * Exception handling no-ops, for more economical byte-coding than SRC_TRYFIN