8280964: [Linux aarch64] : drawImage dithers TYPE_BYTE_INDEXED images incorrectly

[prrace]

As per the bug evaluation, the root of this issue is that on this platform "char" is treated as "unsigned char"
and the code here expects it to be "signed char", so we need to make it explicitly so.
For all other supported platforms this is a no-op since that is the default elsewhere.
So this should be a safe fix, and the updated JDK has been tested on all platforms.

---

Progress

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Issue

• JDK-8280964: [Linux aarch64] : drawImage dithers TYPE_BYTE_INDEXED images incorrectly

Reviewers

• Sergey Bylokhov (@mrserb - Reviewer)
• Dmitry Markov (@dmarkov20 - Reviewer)

Reviewing

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Webrevs

• 00: Full (123a4d3d)

[openjdk]

@prrace This change now passes all automated pre-integration checks.

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After integration, the commit message for the final commit will be:

8280964: [Linux aarch64] : drawImage dithers TYPE_BYTE_INDEXED images incorrectly

Reviewed-by: serb, dmarkov

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At the time when this comment was updated there had been 12 new commits pushed to the master branch:

• e0b4962: 8282190: Typo in javadoc of java.time.format.DateTimeFormatter#getDecimalStyle
• e1c98bd: 8281523: Accessibility: Conversion from string literal loses const qualifier
• cc7cf81: 8280861: Robot color picker broken on Linux with scaling above 100%
• d7a706a: 8253757: Add LLVM-based backend for hsdis
• bdae1d8: 8282147: [TESTBUG] waitForIdle after creating frame in JSpinnerMouseAndKeyPressTest.java
• 51f4420: 8282130: (bf) Remove unused ARRAY_BASE_OFFSET, ARRAY_INDEX_SCALE from read-only Heap Buffers
• 34aae32: 8282166: JDK-8282158 changed ECParameters' package by accident
• c5d9142: 8282096: G1: Remove redundant checks in G1CardSet::free_mem_object
• 52a85d8: 8282158: ECParameters InvalidParameterSpecException messages missed ECKeySizeParameterSpec
• 4e0b81c: 8281544: assert(VM_Version::supports_avx512bw()) failed for Tests jdk/incubator/vector/
• ... and 2 more: https://git.openjdk.java.net/jdk/compare/d7f31d0d53bfec627edc83ceb75fc6202891e186...master

As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[prrace]

/integrate

[openjdk]

Going to push as commit 6f882de.
Since your change was applied there have been 25 commits pushed to the master branch:

• 2557ef8: 8282276: Problem list failing two Robot Screen Capture tests
• 6445ee4: 5041655: (ch) FileLock: negative param and overflow issues
• 7feabee: 8261407: ReflectionFactory.checkInitted() is not thread-safe
• 58e1882: 8282042: [testbug] FileEncodingTest.java depends on default encoding
• 3cb3867: 8281315: Unicode, (?i) flag and backreference throwing IndexOutOfBounds Exception
• 957dae0: 8280958: G1/Parallel: Unify marking code structure
• e44d067: 8244593: Clean up GNM/NM after JEP 381
• 41355e2: 8276686: Malformed Javadoc inline tags in JDK source in /java/util/regex/Pattern.java
• 022d807: 8271008: appcds/*/MethodHandlesAsCollectorTest.java tests time out because of excessive GC (CodeCache GC Threshold) in loom
• ab6d8e6: 8260328: Drop redundant CSS properties from java.desktop HTML files
• ... and 15 more: https://git.openjdk.java.net/jdk/compare/d7f31d0d53bfec627edc83ceb75fc6202891e186...master

Your commit was automatically rebased without conflicts.

[openjdk]

@prrace Pushed as commit 6f882de.

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