Integrated: 8311691: C2: Remove legacy code related to PostLoopMultiversioning

[Pengfei Li]

On Tue, 11 Jul 2023 09:56:51 GMT, Pengfei Li <pli at openjdk.org> wrote:

> As discussed in JDK-8308994, we are working on re-implementation of post loop vectorization and planning to refactor current SuperWord code. As nobody is using or maintaining the old implementation now, to make the refactoring work easier, we propose to remove the legacy code of the old implementation first.
> 
> This patch removes all code realted to `PostLoopMultiversioning` inside and outside SuperWord. After the removal, `SLP_extract()` in SuperWord should only work on main loops. So we also removed all `is_main_loop()` checks inside and added assertions instead.
> 
> Tested with hotspot::hotspot_all_no_apps, jdk tier1~3, langtools tier1 and 100k fuzzer tests on x86 and AArch64, no issue is found.

This pull request has now been integrated.

Changeset: a38582e9
Author:    Pengfei Li <pli at openjdk.org>
URL:       https://git.openjdk.org/jdk/commit/a38582e941c0234e76d1dbea60c731c83d2c9977
Stats:     608 lines in 9 files changed: 7 ins; 564 del; 37 mod

8311691: C2: Remove legacy code related to PostLoopMultiversioning

Reviewed-by: kvn, sviswanathan

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PR: https://git.openjdk.org/jdk/pull/14824