Buffer ARM sequential fetch results and refill target pairs after branches, PC writes, and machine exception entry. Stage advances transactionally, defer speculative fetch diagnostics, and preserve buffered words across CPU/DMA stores and host edits. Add explicit CPU pipeline invalidation for debugger repair and memory rebinding.
Add 15 original instruction-buffer regressions. Keep full-state rollback equality while distinguishing architectural comparisons in semantic tests. Update the display error test for an already buffered branch. Document evidence and separate remaining Thumb, bus-history, and timing work.
Validated on Darwin arm64: 967 workspace and 898 core/demo tests in each debug/release profile, 39 Python tests, native ROM windows, ten window smoke modes, fmt, clippy, and rustdoc. Public ARM/Thumb/memory/BIOS reports and nominal cycles remain unchanged.
Retain one pending non-sequential resume after successful DMA. Apply it to the next nominal non-refill code access and consume it only on successful CPU or IRQ progress. Preserve failed-step atomicity, host and idle isolation, existing refill costs, and WAITCNT ordering.
Add 13 original regressions for ARM/Thumb widths, ROM wait settings, sources, preemption, retries, mixed APIs, idle states, and interrupt timing. Record pinned hardware-test source and emulator evidence without claiming physical-hardware or full-pipeline conformance.
Validated on Darwin arm64: 952 workspace and 883 core/demo tests per debug/release profile, 39 Python tests, native ROM windows, ten window smoke modes, fmt, clippy, and rustdoc. Public ARM/Thumb/memory/BIOS reports remain unchanged.
Update existing Thumb IWRAM continuation lanes from successful DMA reads and writes before the resumed PC+4 snapshot. Keep channel halfword duplication separate from actual lane accesses. Preserve atomic errors, cold-entry diagnostics, IRQ invalidation, and nominal timing.
Add original DMA matrices and resume regressions; update prior invalidation expectations. Record pinned ares and jgenesis evidence and explicit limits for cross-state history, general open bus, and sub-instruction arbitration.
Validated on Darwin arm64: 939 workspace and 870 core/demo tests per debug/release profile, 39 Python tests, native ROM windows, ten window smoke modes, fmt, clippy, and rustdoc. Public ARM/Thumb/memory/BIOS reports remain identical to the previous results.
Retain independent known data across DMA blocks. Duplicate mapped halfword sources and select the destination lane for blocked sources below work RAM. Keep cold history diagnostic, commit only successful units, and preserve separate CPU/BIOS history rules.
Add 13 original regressions and pinned source research. CPU resume ownership, general DMA open bus, and IWRAM DMA lane effects remain explicit limits.
Validated on Darwin arm64: 930 workspace and 861 core/demo tests in debug and release, 39 Python tests, native ROM windows, ten window smoke modes, fmt, clippy, and rustdoc. Public ARM/Thumb/memory/BIOS reports match the previous results exactly.
After successful refill instructions, sample the Thumb IWRAM target and target+2 halfwords to establish bus history. Share ARM/Thumb refill classification with nominal timing. Respect restored instruction state, completed data accesses, region limits, and diagnostic rollback; keep instruction execution and nominal costs unchanged.
Add original regressions for ARM/Thumb BX, Thumb branches and BL, PC writes, stack/block PC loads, status-restoring returns, real SWI/IRQ returns, both target alignments, mirrors/wrap, captured sample ordering, load lanes, failure retention, BIOS isolation, and DMA invalidation. Document official ARM7TDMI refill evidence and the distinction from a full pipeline.
Darwin arm64 validation: 917 workspace tests and 848 core/demo tests per debug/release profile; 39 preparation tests; native ROM windows in both profiles; ten graphics/window smoke modes; fmt, clippy, and rustdoc. Public ARM, Thumb, memory, and BIOS reports remain identical to prior passing results and between profiles. Cold startup, ARM-target refill history, and DMA-to-CPU ordering remain incomplete; no hardware-conformance or commercial-game claim.
Track a separate IWRAM latch with known lanes and transactional updates. Sequential Thumb prefetches and IWRAM byte/halfword/word reads and writes drive only addressed lanes. Other regions and host inspection do not replace the latch. Failed instructions discard staged changes.
Keep cold, refill, discontinuous-entry, IRQ, and DMA-transition history conservative. Share Thumb refill classification with nominal timing, including PC writes to fallthrough. Successful DMA and accepted machine IRQs invalidate history; failed DMA preserves it. Document source evidence, bounded scope, and remaining hardware-validation limits.
Add original lane, alignment, mirror/wrap, signed/unaligned-load, mode, block-transfer, rollback, isolation, control-flow, IRQ/DMA, and nominal-cost regressions. Darwin arm64 validation: 905 workspace tests and 836 core/demo tests per debug/release profile; 39 preparation tests; native ROM windows in both profiles; ten graphics/window smoke modes; fmt, clippy, and rustdoc. Public ARM, Thumb, memory, and BIOS reports remain identical to prior passing reports and between profiles.
Repeat the mapped PC+4 halfword for Thumb code in EWRAM, palette RAM, VRAM, and ROM. Use the aligned PC+4 word for BIOS/OAM. Keep retained BIOS history separate from current unused-memory reads. Reuse one instruction snapshot without extra data cycles or host/fetch/DMA fallbacks.
Keep IWRAM and 16 MiB region-crossing fetches diagnostic until prior bus history is modeled. Add original regressions for regions, alignments, mirrors, physical wrap, signed and unaligned loads, block/stack/PC loads, aliases, modes, short ROMs, strict errors, BIOS isolation, and nominal device progression. Record documented rules and remaining limits.
Darwin arm64 validation: 890 workspace tests and 821 core/demo tests in each of debug and release; 39 preparation tests; native ROM windows in both profiles; ten window/graphics smoke modes; fmt, clippy, and rustdoc. Public ARM, Thumb, memory, and BIOS reports remain identical to previous passing results and between profiles. No physical-hardware or independent public Thumb open-bus conformance claim.
Snapshot the full word at (executing PC+4)&~3 for Thumb BIOS execution, using strict image reads and incoming instruction state. Keep ARM PC+8 open bus separate and unchanged. Commit snapshots only after successful steps; preserve diagnostic behavior for unavailable lookahead.
Add original regression coverage for both code alignments, load widths and lanes, signed and unaligned values, processor modes, sequential fetches, ARM/Thumb transitions, SWI, RAM-backed POP exits, BIOS boundaries, failure retention, and nominal device progression. Record source evidence and explicit pipeline/hardware-validation limits.
Darwin arm64 validation: 878 workspace tests and 809 core/demo tests in each of debug and release; 39 Python tests; native ROM window tests in both profiles; ten window/graphics smoke modes; fmt, clippy, and rustdoc. Public ARM, Thumb, memory, and BIOS reports match prior passing reports and match between profiles. No physical-hardware validation claimed.
Place skipped compatibility data at boot, SoftReset, SWI, and IRQ exit PC+8 locations. Preserve the real IRQ callback return instruction as its readback word. Keep CPU and memory behavior image-derived, including caller-supplied images.
Add original boundary, load-lane, caller-state, wait, supplied-image, and builder-fixup regressions. Document the historical failures, research decision, passing public BIOS checkpoint, and remaining fetch-history limits.
Validated on Darwin arm64: 868 workspace tests in debug and release; 799 core/demo tests separately in both profiles; 39 preparation tests; native ROM window tests in both profiles; ten graphics/window smoke modes; fmt, clippy, and rustdoc. Hash-verified public ARM, Thumb, memory, and BIOS suites pass unchanged with identical debug/release reports. BIOS: r12=0, 17606 steps, 197456 nominal cycles, one IRQ entry.
Compare the current trace with GBATEK, the pinned public test, Smolka firmware analysis, and mGBA software BIOS behavior. Distinguish generic image-derived protection from replacement firmware compatibility. Plan guarded PC+8 compatibility data in the generated BIOS instead of test-specific bus overrides.
