RFR: 8310524: C2: record parser-generated LoadN nodes for IGVN [v3]

[Roberto Castañeda Lozano]

On Wed, 6 Dec 2023 12:57:05 GMT, Daniel Lundén <duke at openjdk.org> wrote:

>> This changeset fixes an issue where LoadN nodes were not recorded during bytecode parsing for later revisit in IGVN, in some cases resulting in missed optimization opportunities (see, e.g., the included new regression test).
>> 
>> Changes:
>> - Make sure to record newly added LoadN-nodes for IGVN in `GraphKit::make_load`.
>> - Add a regression test.
>> 
>> ### Testing
>> - tier1, tier2, tier3, tier4, tier5 (windows-x64, linux-x64, linux-aarch64, macosx-x64, macosx-aarch64)
>
> Daniel Lundén has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Switch to @DontInline

Marked as reviewed by rcastanedalo (Reviewer).

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PR Review: https://git.openjdk.org/jdk/pull/16967#pullrequestreview-1767526462