8389912: [REDO] Regression >6% on Crypto-MLDSA.sign on x64

[dwhite-intel]

Re-enables cisc-spilling for legacy x86 instructions (the hasPredicateSubset() part) from the original PR (#31686).

The predicate matching code in formsself.cpp insisted that both the original and replacement "instructs" have identical predicates.

This PR loosens this requirement to also allow replacing an instruct with a predicate by an instruct without a predicate - the replacement instruct is logically more general than the original instruct that only applies if the predicate is true.

But now, don't enable cisc-spilling for new three-operand (NDD) APX instructions (the MatchNode::cisc_spill_match() part).

Did tiers 1-3 testing with/without APX enabled.

Performance tests showed that this PR does fix the regression in the MLDSA test (when running with -XX:+UseFPUForSpilling). Another PR in the meantime disabled UseFPUForSpilling by default, which also fixed the regression. This PR on top of that PR gives a boost slightly above R2R variation.

Checking cisc-enabled instructions shows that the NDD instruction are not getting cisc spilled, but the original x86 legacy instructions get the same cisc-spilling support as prior to APX tuning.

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• JDK-8389912: [REDO] Regression >6% on Crypto-MLDSA.sign on x64 (Bug - P3)

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