RFR(T) 8234628 Change BasicHashTables::new_entry() to use clamp()

[Daniel D. Daugherty]

Thumbs up! I agree that this is a trivial change and doesn't have to
wait for 24 hours.

Dan


On 6/2/20 11:33 AM, Ioi Lam wrote:
> https://bugs.openjdk.java.net/browse/JDK-8234628
>
> A small clean up. Rewrite the code to say what it means to do
>
> Tested with mach5 tier1/2
>
>
> $ hg diff
> diff -r 37c816b004e5 src/hotspot/share/utilities/hashtable.cpp
> --- a/src/hotspot/share/utilities/hashtable.cpp    Tue Jun 02 01:08:44 
> 2020 -0700
> +++ b/src/hotspot/share/utilities/hashtable.cpp    Tue Jun 02 08:24:59 
> 2020 -0700
> @@ -61,7 +61,8 @@
>
>    if (entry == NULL) {
>      if (_first_free_entry + _entry_size >= _end_block) {
> -      int block_size = MIN2(512, MAX3(2, (int)_table_size / 2, 
> (int)_number_of_entries));
> +      int block_size = MAX2((int)_table_size / 2, 
> (int)_number_of_entries); // pick a reasonable value
> +      block_size = clamp(block_size, 2, 512); // but never go out of 
> this range
>        int len = _entry_size * block_size;
>        len = 1 << log2_int(len); // round down to power of 2
>        assert(len >= _entry_size, "");
>
> Thanks
> - Ioi