[X64] [En3Tho] Fix Unnecessary sign-extension for `(nuint)span.Length`

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Build completed in 1 hour 42 minutes.
dotnet/runtime#88136

CoreLib diffs

Found 1 files with textual diffs.

Summary of Code Size diffs:
(Lower is better)

Total bytes of base: 6608783
Total bytes of diff: 6608783
Total bytes of delta: 0 (0.00 % of base)


0 total files with Code Size differences (0 improved, 0 regressed), 1 unchanged.

0 total methods with Code Size differences (0 improved, 0 regressed), 52948 unchanged.

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Frameworks diffs

Diffs

Found 257 files with textual diffs.

Summary of Code Size diffs:
(Lower is better)

Total bytes of base: 37895630
Total bytes of diff: 37895630
Total bytes of delta: 0 (0.00 % of base)


0 total files with Code Size differences (0 improved, 0 regressed), 256 unchanged.

0 total methods with Code Size differences (0 improved, 0 regressed), 232555 unchanged.

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Artifacts:

• build-artifacts-main.zip (646 MB)
• build-clr-checked-main.zip (71 MB)
• build-artifacts-pr.zip (646 MB)
• build-clr-checked-pr.zip (71 MB)
• jit-diffs-corelib.zip (45 MB)
• diff-corelib.txt (433 B)
• diff-frameworks.txt (440 B)
• jit-diffs-frameworks.zip (246 MB)
• build-logs.txt (1 MB)

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