Back out my last commit due to orange.

js/src/jsemit.cpp

@@ -4514,7 +4514,7 @@ js_EmitTree(JSContext *cx, JSCodeGenerator *cg, JSParseNode *pn)
             stmtInfo.update = top;
             if (!js_SetSrcNoteOffset(cx, cg, noteIndex, 0, jmp - beq))
                 return JS_FALSE;
-            if (!js_SetSrcNoteOffset(cx, cg, noteIndex, 1, top - beq))
+            if (!js_SetSrcNoteOffset(cx, cg, noteIndex, 1, top - jmp))
                 return JS_FALSE;
         }
 

js/src/jsopcode.cpp

@@ -3269,7 +3269,7 @@ Decompile(SprintStack *ss, jsbytecode *pc, intN nb, JSOp nextop)
                          * the second if, so we simply decompile it and start
                          * over at label if_again.
                          */
-                        cond = js_GetSrcNoteOffset(sn, 1) - tail;
+                        cond = js_GetSrcNoteOffset(sn, 1);
                         if (cond != 0) {
                             DECOMPILE_CODE(pc + oplen, cond - oplen);
                             pc += cond;