Snapshot mapped PC+8 bytes for ARM data reads in the documented unused ranges. Preserve strict host/fetch/Thumb/DMA diagnostics, missing-ROM errors, existing write rules, and nominal timing. Add original regressions and document the bounded model.
The unmodified pinned jsmolka ARM ROM now reaches its verified checkpoint with r12=0 in debug and release: 1344 steps and 11257 nominal cycles. No ROM, manifest, or assertion changes.
Validated on Darwin arm64: 842 workspace tests in debug and release; 773 core/demo tests separately; Python adapter tests; native ROM windows; all ten demo window smoke tests; fmt, clippy, and rustdoc.
Allow ARM LDR/LDRB/LDRH/LDRSB/LDRSH to share non-PC base and destination registers with writeback. Keep the loaded value after computing addresses from incoming operands. Preserve PC restrictions, unsupported user transfers, store behavior, and atomic memory diagnostics.
Add original regressions for index modes, offsets, widths, alignment, sign extension, all active banks, timing, I/O/IRQ ordering, and failures. The unchanged pinned public ARM ROM progresses past tests 360 and 361, then fails at test 362 on an unmapped 0x80000000 read; no full-suite pass is claimed.
Verified on Darwin arm64: debug/release workspace and core suites, Python adapter tests, Clippy, rustdoc, native ROM-window checks, and all ten demo smoke tests. Document the new behavior and next memory-access blocker.
Add a standard-library Python adapter and SHA-256/size lock for jsmolka/gba-tests ARM at a7113b67e63f83a9b321696ddd7042ccfad6c881. Retain sources and license locally, refuse tracked output paths or overwrites, verify offline inputs, and generate the source-verified eval/r12 suite checkpoint without patching the ROM.
Add Python to the pinned Nix shell, offline adapter regressions, and public-test provenance/results documentation. Verified on Darwin arm64: Rust debug/release workspace tests, adapter tests, Clippy, rustdoc, native ROM and all demo window checks. The public test remains a failing baseline at instruction 0xe5b00004, PC 0x0800132c, in test 360.
