RFR: 8349138: Optimize Math.copySign API for Intel e-core targets [v2]

[Jatin Bhateja]

On Thu, 13 Feb 2025 11:01:34 GMT, Quan Anh Mai <qamai at openjdk.org> wrote:

> > Also currently, logical And mask is a long value, in case we opt-in for new AndF/D node creation, to preserve the IR semantics we would also need to perform an integral to floating point constant conversion, this will incur additional memory load penalty since floating-point constants are emitted into the constant table before native method body.
> 
> That means we can improve the generation of floating-point constants.
> 
> The reason I object this approach is that it is short-sighted. It's not like we cannot generate similar machine code with the more general approach. Furthermore, after we do `AndF` transformations, this patch is redundant and can be removed entirely.

Hi @merykitty , the patch intends to absorb domain crossover penalty due to the movement of floating point arguments to GPRs, if we introduce a floating-point constant load penalty then we may degrade the performance.

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PR Comment: https://git.openjdk.org/jdk/pull/23386#issuecomment-2671907468