RFR: 8301995: Move invokedynamic resolution information out of ConstantPoolCacheEntry [v12]

[Andrew Haley]

On Thu, 23 Mar 2023 15:37:27 GMT, Matias Saavedra Silva <matsaave at openjdk.org> wrote:

>> The current structure used to store the resolution information for invokedynamic, ConstantPoolCacheEntry, is difficult to interpret due to its ambigious fields f1 and f2. This structure can hold information for fields, methods, and invokedynamics and each of its fields can hold different types of values depending on the entry. 
>> 
>> This enhancement proposes a new structure to exclusively contain invokedynamic information in a manner that is easy to interpret and easy to extend.  Resolved invokedynamic entries will be stored in an array in the constant pool cache and the operand of the invokedynamic bytecode will be rewritten to be the index into this array.
>> 
>> Any areas that previously accessed invokedynamic data from ConstantPoolCacheEntry will be replaced with accesses to this new array and structure. Verified with tier1-9 tests.
>> 
>> The PPC was provided by @reinrich and the RISCV port was provided by @DingliZhang and @zifeihan.
>> 
>> This change supports the following platforms: x86, aarch64, PPC, and RISCV
>
> Matias Saavedra Silva has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Andrew comments aarch64

src/hotspot/cpu/aarch64/templateTable_aarch64.cpp line 2348:

> 2346:   address entry = CAST_FROM_FN_PTR(address, InterpreterRuntime::resolve_from_cache);
> 2347:   __ mov(method, code); // this is essentially Bytecodes::_invokedynamic
> 2348:   __ call_VM(noreg, entry, method); // Example uses temp = rbx. In this case rbx is method

What is `rbx` ?

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PR Review Comment: https://git.openjdk.org/jdk/pull/12778#discussion_r1147401509