RFR: 8298241: Replace C-style casts with JavaThread::cast

[Coleen Phillimore]

On Wed, 14 Dec 2022 22:22:48 GMT, David Holmes <dholmes at openjdk.org> wrote:

> This is a simple cleanup RFE to get rid of old-style C casts in relation to JavaThread.
> 
> In many cases involving NULL/nullptr the cast could just be dropped. Sometimes a static cast is needed to disambiguate overloads.
> 
> A couple of reinterpret_cast are needed when doing int/ptr conversion.
> 
> static_cast is used for void* conversion.
> 
> The other changes should be self explanatory.
> 
> The changes in
> 
> src/hotspot/os_cpu/bsd_aarch64/javaThread_bsd_aarch64.cpp
> src/hotspot/os_cpu/windows_aarch64/javaThread_windows_aarch64.cpp
> 
> are a bit more extensive. That code was using an alias for `this` which is completely unnecessary (and the alias creation was using the cast). This could be factored out if thought necessary.
> 
> I grep'd as best I could for the old C-style casts but can't be certain I got them all.
> 
> Testing: 
>  - all builds in our tiers1-5
>  - local linux x64 product, slowdebug and fastdebug
>  - GHA (TBD)
>  - Sanity testing tiers 1-3
> Thanks.

Looks good!

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Marked as reviewed by coleenp (Reviewer).

PR: https://git.openjdk.org/jdk/pull/11682