RFR(S) 8246181: Avoid walking SymbolTable during -Xshare:dump

[Calvin Cheung]

Hi Yumin,

Code changes look good.

I guess the following assert isn't applicable to the new code anymore 
since the SymbolTable::do_add_if_needed will be called for non-permanent 
symbols?

1244     assert((*sym)->is_permanent(), "archived symbols must be 
permanent");

Are we archiving more symbols with this change?

thanks,

Calvin

On 6/23/20 2:44 PM, Yumin Qi wrote:
> Hi, Please review
>
> Bug: https://bugs.openjdk.java.net/browse/JDK-8246181
>
> Webrev:http://cr.openjdk.java.net/~minqi/2020/8246181/webrev-00/
>
>
> Summary: This is a little different from the bug suggested 
> implementation. To avoid working the SymbolTable during dump, the 
> symbol is added to a global array when it is created, 
> SymbolTable::do_add_if_needed. The symbol only created once during its 
> lifetime. There is just little performance overhead for runtime.
>
>
> Tests: local jtreg on runtime/cds/appcds for debug/release.
>
> mach5: tier1,tier2,tier4
>
>
> Thanks
>
> Yumin
>