8374489: Template Library: need to tag Float16.float16ToRawShortBits as having non-deterministic result because of multiple NaN bit patterns

[eme64]

In JDK-8370922, I added Float16 support to the Template Library. I missed to tag Float16.float16ToRawShortBits as having non-deterministic result.

We need to do that, just like for float and double equivalents:
Arithmetic operations (e.g. add, mul, fma, ...) are allowed to pick either input if it gets two NaNs of different bit patterns.
That way, those operations can generate different NaN bit patterns depending on if we use interpreter/C1/C2.
If we now convert to raw bits, we get different bits, and would wrongly conclude that we get a wrong result.

Since this is a test-bug, I have no regression test. But I verified it manually, that with the same seed (for the ExpressionFuzzer) that fails before this change, we now succeed after the change.

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Issue

• JDK-8374489: Template Library: need to tag Float16.float16ToRawShortBits as having non-deterministic result because of multiple NaN bit patterns (Bug - P4)

Reviewers

• Christian Hagedorn (@chhagedorn - Reviewer)
• Vladimir Kozlov (@vnkozlov - Reviewer)

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@eme64 This change now passes all automated pre-integration checks.

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8374489: Template Library: need to tag Float16.float16ToRawShortBits as having non-deterministic result because of multiple NaN bit patterns

Reviewed-by: chagedorn, kvn

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At the time when this comment was updated there had been 6 new commits pushed to the master branch:

• 27dbdec: 8374217: Remove IO.java test from AOT ProblemList
• 4458cab: 8367627: C2: Missed Ideal() optimization opportunity with MemBar
• 6ae3e06: 8373508: C2: sinking CreateEx out of loop breaks the graph
• ... and 3 more: https://git.openjdk.org/jdk/compare/6eaabed55ca4670d8c317f0a4323ccea4dd0b9ca...master

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[chhagedorn]

Looks good and trivial!

[vnkozlov]

Good.

[eme64]

@vnkozlov @chhagedorn Thanks for the reviews!

/integrate

[openjdk]

Going to push as commit 2cb228e.
Since your change was applied there have been 11 commits pushed to the master branch:

• 2fbc416: 8374441: (fs) FileSystemProvider.readAttributesIfExists throws "Not a directory" when element in path is not directory should return null for ENOTDIR (unix)
• d063c95: 8374507: GHA: Limit debug symbols generation to conserve disk space
• de81d38: 8374456: JVM crashes with "assert(resolved_method->method_holder()->is_linked()) failed: must be linked" when run with large value for PreallocatedOutOfMemoryErrorCount
• ... and 8 more: https://git.openjdk.org/jdk/compare/6eaabed55ca4670d8c317f0a4323ccea4dd0b9ca...master

Your commit was automatically rebased without conflicts.

[openjdk]

@eme64 Pushed as commit 2cb228e.

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