[jdk17] RFR: 8268366 Incorrect calculation of has_fpu_registers in C1 linear scan [v2]

[Christian Hagedorn]

On Fri, 11 Jun 2021 20:54:26 GMT, Dean Long <dlong at openjdk.org> wrote:

>> If there is a mismatch between bytecode use of floating point and generated IR, has_fpu_registers can get an incorrect value and result in a crash or assert.  This PR adds a missing case for the computation of has_fpu_registers, restores an assert that was removed, adds a bailout for non-debug builds, and adds a test.
>
> Dean Long has updated the pull request incrementally with one additional commit since the last revision:
> 
>   suggested cleanup

Looks good, thanks for the changes!

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Marked as reviewed by chagedorn (Reviewer).

PR: https://git.openjdk.java.net/jdk17/pull/10