RFR: 8269823: JFR: Eliminate 'is_large' check for native JFR event if the size range is certain

[Denghui Dong]

On Fri, 2 Jul 2021 15:20:50 GMT, Denghui Dong <ddong at openjdk.org> wrote:

> Hi,
> 
> Could I have a review of this improvement that eliminates 'is_large' if the event size range is certain?
> 
> JDK-8246260 introduced event large checks to reduce the recording size.
> This check could be eliminated at compile/build time when one of the following conditions is satisfied:
> 1. if the max size is < 128
> 2. if the min size is >= 128
> 
> The max size and the min size could be computed for the most native events at the generation phase.
> 
> And I think this improvement may also be done for JDK events.

I think some other improvements could be done based on the max/min event size, e.g. merge `ensure_size` operations

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PR: https://git.openjdk.java.net/jdk/pull/4670