RFR: 8330465: Stable Values and Collections (Internal) [v5]

[Per Minborg]

On Thu, 16 May 2024 11:14:16 GMT, Chen Liang <liach at openjdk.org> wrote:

>> The idea here is to have the most likely value in the middle... Not sure if that motivates the added complexity though.
>
> Is there any refernce on how/why the middle entry in a tableswitch instruction is the fastest?

It is only in a _lookupswitch_ that this becomes relevant. The above code will generate a *tableswitch* so I think it is safe to simplify the code and remove the DUMMY.


  private V orThrowVolatile();
    descriptor: ()Ljava/lang/Object;
    flags: (0x0002) ACC_PRIVATE
    Code:
      stack=1, locals=1, args_size=1
         0: aload_0
         1: invokevirtual #15                 // Method stateVolatile:()I
         4: tableswitch   { // 0 to 4
                       0: 40
                       1: 44
                       2: 46
                       3: 51
                       4: 56
                 default: 60
            }
            ...

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PR Review Comment: https://git.openjdk.org/jdk/pull/18794#discussion_r1603214742