RFR: 8276846: JDK-8273416 is incomplete for UseSSE=1

[Aleksey Shipilev]

On Tue, 9 Nov 2021 11:52:50 GMT, Aleksey Shipilev <shade at openjdk.org> wrote:

> When doing the fix for [JDK-8273416](https://bugs.openjdk.java.net/browse/JDK-8273416), I made a mistake of not running with `UseSSE=1`. That one highlights a bug (see JIRA for reproducer): I have misjudged that `float` and `double` args are handled at the same SSE levels, which they are not. `doubles` uses FPU with SSE={0,1}, and `float` uses FPU with SSE={0}. See for example the blurbs in `MacroAssembler::{load|store}_{float|double}`. So the new predicate for `regFPR` argument mishandles UseSSE=1 case: we should not allow `castFF_PR` to match then.
> 
> Additional testing:
>  - [x] Linux x86_32 `tier1` with `-XX:UseAVX=0 -XX:UseSSE=0`
>  - [x] Linux x86_32 `tier1` with `-XX:UseAVX=0 -XX:UseSSE=1`
>  - [x] Linux x86_32 `tier1` with `-XX:UseAVX=0 -XX:UseSSE=2`
>  - [x] Linux x86_32 `tier1` with `-XX:UseAVX=0 -XX:UseSSE=3`
>  - [x] Linux x86_32 `tier1` with `-XX:UseAVX=0 -XX:UseSSE=4`
>  - [x] Linux x86_32 `tier1` with `-XX:UseAVX=1 -XX:UseSSE=4`
>  - [x] Linux x86_32 `tier1` with `-XX:UseAVX=2 -XX:UseSSE=4`

Thanks, folks!

-------------

PR: https://git.openjdk.java.net/jdk/pull/6308