Adds ccmp logic into emitter backend.

[anthonycanino]

Overview

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This PR adds APX new ccmp instruction to the X86 backend.

Design

For reference, there is a unique extended evex encoding for ccmp:

where SC0 - SC3 encode the condition for ccmp to conditionally execute on (please see SDM Vol 1, Appendix B). If the status codes fail to satisfy the condition encoded by SC0 - SC3, no compare will be performed, and the OF, SF, ZF, and CF flags will be set to the default flag value (DFV) fields of, sf, zf and cf.

Testing

Note: The testing plan for APX work has been discussed in #106557, please refer to that PR for details, only results and comments will be posted in this PR. Results

[anthonycanino]

1. Emitter unit tests

The left is output from JitDisasm, and right from JitLateDisasm.

2. Intel SDE testing

Test run with SDE:

3. SuperPMI results

Diffs are based on 2,623,457 contexts (1,043,127 MinOpts, 1,580,330 FullOpts).

MISSED contexts: 2,983 (0.11%)

Base JIT options: JitBypassApxCheck=1

Diff JIT options: JitBypassApxCheck=1

No diffs found.

Details

Context information

Collection	Diffed contexts	MinOpts	FullOpts	Missed, base	Missed, diff
aspnet.run.windows.x64.checked.mch	126,540	63,098	63,442	2,665 (2.06%)	2,665 (2.06%)
benchmarks.run.windows.x64.checked.mch	28,757	4	28,753	0 (0.00%)	0 (0.00%)
benchmarks.run_pgo.windows.x64.checked.mch	105,618	52,679	52,939	0 (0.00%)	0 (0.00%)
benchmarks.run_tiered.windows.x64.checked.mch	55,912	38,403	17,509	0 (0.00%)	0 (0.00%)
coreclr_tests.run.windows.x64.checked.mch	582,221	349,625	232,596	0 (0.00%)	0 (0.00%)
libraries.crossgen2.windows.x64.checked.mch	280,377	16	280,361	0 (0.00%)	0 (0.00%)
libraries.pmi.windows.x64.checked.mch	295,086	6	295,080	0 (0.00%)	0 (0.00%)
libraries_tests.run.windows.x64.Release.mch	751,895	517,237	234,658	0 (0.00%)	0 (0.00%)
libraries_tests_no_tiered_compilation.run.windows.x64.Release.mch	342,818	22,045	320,773	0 (0.00%)	0 (0.00%)
realworld.run.windows.x64.checked.mch	24,824	2	24,822	0 (0.00%)	0 (0.00%)
smoke_tests.nativeaot.windows.x64.checked.mch	29,409	12	29,397	318 (1.07%)	318 (1.07%)
	2,623,457	1,043,127	1,580,330	2,983 (0.11%)	2,983 (0.11%)

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