8359955: Regressions ~7% in several J2DBench in 25-b26

[gredler]

Addresses recent slight performance regressions in some J2DBench benchmarks focused on text drawing.

CCharToGlyphMapper and CompositeGlyphMapper cache glyph IDs, but after JDK-8353230 they weren't caching glyph IDs for chars which might be affected by the raw / non-raw glyph distinction, since the cached value may not be correct if we ask for a raw glyph ID one time, but a non-raw glyph ID the next time (or vice versa). This caching exception was the reason for the slightly degraded performance (the CCharToGlyphMapper behavior was affecting macOS, and the CompositeGlyphMapper behavior was affecting some versions of Windows). This change splits the cache in each of these two classes into two caches, one for raw glyph IDs and one for non-raw glyph IDs, so that all glyphs can benefit from caching.

All of the font tests (make test TEST="jtreg:test/jdk/java/awt/font") pass for me locally with this change on Linux, macOS and Windows.

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Issue

• JDK-8359955: Regressions ~7% in several J2DBench in 25-b26 (Bug - P4)

Reviewers

• Phil Race (@prrace - Reviewer)

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8359955: Regressions ~7% in several J2DBench in 25-b26

Reviewed-by: prr

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At the time when this comment was updated there had been 171 new commits pushed to the master branch:

• cd50d78: 8361300: Document exceptions for Unsafe offset methods
• 241808e: 8364269: Simplify code cache API by storing adapter entry offsets in blob
• 1b3e231: 8360048: NMT crash in gtest/NMTGtests.java: fatal error: NMT corruption: Block at 0x0000017748307120: header canary broken
• ... and 168 more: https://git.openjdk.org/jdk/compare/8477630970b61e3178abd7ac812ed97e181e2684...master

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[mlbridge]

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[prrace]

LGTM. I ran all our automated jtreg tests on all platforms, plus JCK.