Robert Allan JamesandClaude Sonnet 5
a1c9fc7330
FABRIC.md item 4.5d Finding 4: lidt()'s inline asm used a register-only
("r") constraint on the idtr pointer, never telling GCC the asm
dereferences the pointee. At -O2 this let the compiler treat the
256-entry idt[] population loop and idtr_desc's field writes as dead
stores and eliminate them entirely, loading IDTR from uninitialized
stack instead of the real table -- a #GP on the first APIC timer tick
that happened to land on garbage. Same bug class as the earlier
muldiv64 fix (b43e51a): an inline-asm constraint too weak for what the
asm actually touches, invisible at -O0, live at -O2.
Fixed by switching to a memory operand ("m"(*idtr_desc)), matching how
Linux's own load_idt() is written. aarch64/riscv64 checked for the same
pattern -- neither has it, both install their vector/trap tables
entirely in hand-written .S.
Verified: all three architectures boot clean to ok>, POST Failed: 0,
identical dict-hashes across all three under -O2, zero new warnings
vs an -O0 baseline (amd64 3040/3040, aarch64 3041/3041 serial,
riscv64 3037/3037). -O2/-U_FORTIFY_SOURCE landed permanently in
COMMON_CFLAGS.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
src/
Hosted StarForth VM implementation (compiled by the root Makefile).
Bare-metal kernel sources live in src/starkernel/; FORTH word
implementations in src/word_source/; the test harness in
src/test_runner/; platform shims in src/platform/.
Entry point / interpreter core
main.c— CLI entry point, VM init, DoE mode dispatch.vm.c— interpreter loop, stacks, dictionary state (the central runtime file).vm_api.c— external VM API implementation.vm_bootstrap.c— VM bootstrap initialization.vm_debug.c— debugging utilities.vm_time.c— time-related VM operations.vm_internal.h— internal-only declarations shared across thevm_*.cfiles, not part of the publicinclude/vm_api.hsurface.repl.c— REPL read-eval-print loop.cli.c— CLI argument parsing.io.c— I/O operations.log.c— logging infrastructure.
Memory / dictionary / blocks
memory_management.c— dictionary allocator.dictionary_management.c— dictionary allocation and search.dictionary_heat_optimization.c— Loop #1 execution-heat tracking.word_registry.c— word registration system.block_subsystem.c— logical→physical block mapper.blkio_file.c,blkio_ram.c,blkio_factory.c— block I/O backends (file-backed, RAM-backed) and the factory that selects between them.stack_management.c— stack operations.
Physics-driven adaptive runtime (7 feedback loops)
physics_runtime.c— main physics coordinator.physics_hotwords_cache.c— Loop #1 hot-words caching.physics_metadata.c— per-word metadata tracking.physics_pipelining_metrics.c— Loop #4 word-transition prediction.physics_execution_hooks.c— execution instrumentation.rolling_window_of_truth.c— Loop #2 circular execution-history buffer.inference_engine.c— Loops #5/#6, statistical inference (window-width, decay-slope).ssm_jacquard.c— L8 Jacquard steady-state mode selector; consumescompudynamics.cfor tuning-word/config lookups.compudynamics.c— generic compudynamics module (cd_tuning_word(),cd_tuning_vm()); the score/UCB/reward/weight constants for the L8 adaptive table live here, not inssm_jacquard.c.heartbeat_export.c— heartbeat metrics export (CSV export function itself not yet implemented — seedocs/working/architecture/heartbeat_csv_export.md).
Math / measurement
math_portable.c— portable math functions.profiler.c— performance profiling.doe_metrics.c— Design of Experiments metrics (2^7 factorial).
Any .bak file alongside a .c file here (doe_metrics.c.bak,
inference_engine.c.bak, vm.c.bak) is a pre-edit backup left by a past
maintenance script (see scripts/remove_loop_conditionals.sh), not a
build input.