Build TABLESWITCH from sorted arrays in SWITCH

[rootvector2]

SWITCH clones the caller's match/targets arrays and sorts only the clones, but the TABLESWITCH branch fills the table from the original unsorted match/targets, while the LOOKUPSWITCH branch uses matchClone/targetsClone. When the match array is passed unsorted (the class javadoc documents unsorted input and promises to leave the caller's arrays unaltered) and its sorted form is gap-free, the fill loop runs over unsorted keys, so the generated TABLESWITCH gets out-of-order case values padded with default entries. TABLESWITCH.dump then writes low = match[0] and high = match[last] that disagree with the count of offset words emitted, and re-reading the dumped instruction consumes only high - low + 1 offsets, reinterpreting the surplus words as the next instructions.

Fill the table from matchClone/targetsClone to match the LOOKUPSWITCH branch. Found while auditing the switch-generation paths.

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[Copilot]

Pull request overview

This PR fixes incorrect TABLESWITCH generation in SWITCH when the caller provides an unsorted match array whose sorted form is gap-free. The TABLESWITCH table is now built from the already-sorted clones (matchClone/targetsClone), aligning behavior with the LOOKUPSWITCH path and preventing invalid low/high metadata vs. offset table size.

Changes:

• Build the TABLESWITCH mVec/tVec table using matchClone and targetsClone (sorted clones) instead of the original input arrays.
• Add a regression test ensuring an unsorted-but-gap-free match produces a TABLESWITCH with sorted case keys and correctly paired targets.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/main/java/org/apache/bcel/generic/SWITCH.java	Fixes TABLESWITCH table construction to use sorted clones, preventing malformed serialized switches.
src/test/java/org/apache/bcel/generic/SWITCHTest.java	Adds coverage for the unsorted-input, gap-free case to prevent regressions in TABLESWITCH generation.

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[garydgregory]

Merged, thank you @rootvector2 🚀