Files
StarForth/src
Robert Allan James ef9806977a starkernel: item 4.3.3 -- Cartesian coordinate machinery, found and fixed a VARIABLE alignment bug
Adds Module 28 (framebuffer_words.c/.h): PLOT ( x y color -- ), FB-WIDTH,
FB-HEIGHT -- raw hardware-boundary C primitives, kernel-only, no-op on
hosted builds, same pattern as every other module.

Adds capsules/fabric.4th (blocks 4900-4902, mkcapsule --lint clean):
COS45/Z->DELTA/PROJECT/CART-Y/CART-PLOT -- the 45-degree cavalier
orthographic projection and Y-flip, in FORTH per the compose-in-FORTH-first
rule (this is policy, not hardware access).

Found and fixed a second real bug while live-testing CART-PLOT over the
serial socket: defining_word_variable() (defining_words.c) captured
vm->here as a VARIABLE's address with no alignment call first, while
vm_load_cell/vm_store_cell require 8-byte-aligned addresses. This capsule's
VARIABLE ZD landed misaligned (945) purely by chance of what preceded it;
other capsules' variables happened to land aligned by luck, not guarantee.
Real deviation from FORTH-83/ANS, which specifies VARIABLE reserves an
aligned cell. Fixed with vm_align(vm) before capturing addr -- ALIGN
already existed as a word but VARIABLE wasn't calling it.

Verified end-to-end on amd64 via manual serial injection + QEMU screendump:
plotted 4 marker points (origin, +100 X, +100 Y, +50 Z) and confirmed all
landed at hand-calculated raster coordinates, including the diagonal
up-right shift for the Z-axis point -- the projection math is correct, not
just non-crashing. fb/fabric-test-cart-plot.png. 4.3.1's corner diagnostic
still renders correctly in the same shot, confirming no regression.

All three architectures (amd64/aarch64/riscv64) boot clean to ok> with the
DoE completing; dict_hash identical across all three
(0xc7f9adf885e306d2), confirming parity is unaffected.

FABRIC.md item 4.3.3 marked done with full acceptance evidence.
2026-08-07 13:20:52 -04:00
..
2026-08-01 07:49:56 -04:00
2026-08-01 07:49:56 -04:00
2026-08-01 07:49:56 -04:00
2026-08-01 07:49:56 -04:00

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 the vm_*.c files, not part of the public include/vm_api.h surface.
  • 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; consumes compudynamics.c for 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 in ssm_jacquard.c.
  • heartbeat_export.c — heartbeat metrics export (CSV export function itself not yet implemented — see docs/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.