GeezerVison

Simplify twelve existing choice/majority helper return expressions in MD4, MD5, SHA-1, RIPEMD160, RIPEMD320 and SM3.

Nine choice expressions use three bitwise operations instead of four; three majority expressions use four instead of five. The identities preserve Java int behavior and add no calls, branches, guards or local variables. Callers remain unchanged. Already simplified SHA-2/LongDigest helpers are excluded.

Generated and independently checked by the Sandbox mathematics cleanup:
https://github.com/carstenartur/sandbox
Sandbox revision: d426c5cb6098f4377e45bc912469f160c38459ad.
Every selected edit has PRESERVE_JAVA, BITVECTOR_TRUTH_TABLE and guard NONE evidence, and occurs in the actual complete generated sources. The same edits were reproduced in both completed full-corpus scans.

Validation on upstream e40316b:

• 14 existing official digest/HMAC test programs pass before and after, including known vectors, incremental updates, clone/memo restoration, encoded state, million-a and SHA1 interleave tests. Exact success output was checked, not only process exit status.
• Java 25 compilation with --release 8 -Xlint:all -Xmaxwarns 10000 passes. Both complete compiler logs are byte-identical (176 existing warnings).
• Only the six changed digest classes differ among 380 compiled classes per variant.
• javap confirms one fewer bitwise operation in every changed helper.
• git diff --check passes.

No full Gradle build or runtime benchmark is claimed. ChatGPT assisted with extraction, review and validation.