docs: reorganise -- current reference gathered, finished work archived, superseded and dead ideas marked as such
docs/CLAUDE.md Phase 2, 2026-10-14. All moves by git mv; every archived file carries a header saying what it is, why, and where to look instead. - docs/reference/ (new): roadmap and versioning policy, M7.1, word-ACL design, kernel args, hosted acceptance test, dictionary, primitives, ontology, L8 table -- previously spread over docs/, docs/lithosananke/ and docs/03-architecture/. - docs/working/archive/historical/: finished work (session plan, test-gap audit, birthing plan, fix write-ups, the January architecture draft). - docs/working/archive/superseded/: the Hermes-VM Tripod docs and July Hermes designs (-> FABRIC-3.5/3.6), the StarForth roadmap, every working doc already flagged superseded or obsolete. - docs/working/archive/dead/: the hal_* target contract (never adopted), L4Re, metrics-and-knobs. - Papers and proposals into docs/working/papers/. - References rewritten across the repo (not logs/, not docs/patent/); CLAUDE.md's documentation section rewritten. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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rajames
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Claude Opus 5.5
Claude Opus 5.5
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// DEAD (docs triage 2026-10-14). L4Re/Fiasco.OC was removed as a platform target in mid-2026. Instead: .claude/CLAUDE.md (Project Overview). Moved from docs/working/hardware/platform-integration/L4RE_DICTIONARY_ALLOCATION.adoc.
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// Moved from docs/src/platform-integration/L4RE_DICTIONARY_ALLOCATION.adoc to docs/working/scratch/src/platform-integration/L4RE_DICTIONARY_ALLOCATION.adoc on 2026-06-16 (docs reorg Phase 2)
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== Dictionary Allocation Strategy for L4Re
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:toc: left
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:toc-title: Contents
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:toclevels: 3
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xref:../README.adoc[← Back to Documentation Index]
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=== Current Implementation
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StarForth currently uses `+malloc()+` and `+free()+` from the host C
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library for dictionary entry allocation:
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* *Location*: `+src/dictionary_management.c:228+`
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* *Function*: `+vm_create_word()+` uses `+malloc(total)+` to allocate
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DictEntry structures
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* *Cleanup*: `+FORGET+` uses `+free(e)+` to deallocate entries (line 554
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in defining_words.c)
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This works fine for hosted environments but creates a dependency on libc
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heap allocator.
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=== Why This Matters for L4Re/StarshipOS
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==== Issues with Current Approach:
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[arabic]
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. *Heap Dependency*: Requires full malloc implementation in L4Re
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environment
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. *Non-Deterministic*: Heap fragmentation and unpredictable allocation
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behavior
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. *Separate Address Space*: Dictionary entries live outside VM memory
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model
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. *Hard to Introspect*: Can’t dump entire VM state as single memory
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region
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==== Benefits of VM-Based Allocation:
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[arabic]
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. *Zero External Dependencies*: No libc malloc needed
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. *Deterministic*: Simple bump allocator, predictable behavior
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. *Unified Address Space*: Everything in one 5MB VM memory region
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. *Easy Snapshots*: Can serialize entire VM state
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. *Better for Microkernel*: Aligns with L4Re dataspace model
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=== Recommended Approach for L4Re
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==== Strategy: Conditional Compilation
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Add a compile-time flag to switch between malloc and VM-based
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allocation:
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[source,c]
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----
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// In dictionary_management.c
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#ifdef STARFORTH_VM_DICT_ALLOC
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/* VM-based allocation (for L4Re/embedded) */
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DictEntry *entry = dict_alloc_from_vm(vm, total);
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#else
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/* Standard malloc (for hosted environments) */
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DictEntry *entry = (DictEntry *) malloc(total);
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#endif
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----
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==== Memory Layout (VM-Based Mode):
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....
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vm->memory[0...VM_MEMORY_SIZE] (5MB):
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┌──────────────────────────────────────────┐
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│ Dictionary Headers (256KB) │ ← dict_headers_used grows up
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│ - DictEntry structures │
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│ - Allocated via dict_alloc() │
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├──────────────────────────────────────────┤
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│ User Data & Code (variable) │ ← HERE grows up
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│ - Compiled definitions │
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│ - Variables, constants │
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│ - String literals │
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├──────────────────────────────────────────┤
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│ Block Storage (remainder) │
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│ - 1KB blocks for Forth block system │
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└──────────────────────────────────────────┘
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....
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==== Implementation Steps:
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[arabic]
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. *Add Dictionary Allocator* (256KB bump allocator at `+memory[0]+`):
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[source,c]
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----
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static DictEntry *dict_alloc_from_vm(VM *vm, size_t total_bytes) {
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/* Align to cell_t boundary */
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size_t align = sizeof(cell_t);
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total_bytes = (total_bytes + align - 1) & ~(align - 1);
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/* Check space */
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if (vm->dict_headers_used + total_bytes > DICT_HEADERS_MAX) {
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vm->error = 1;
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return NULL;
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}
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/* Allocate from VM memory */
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DictEntry *entry = (DictEntry *)(vm->memory + vm->dict_headers_used);
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vm->dict_headers_used += total_bytes;
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return entry;
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}
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----
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[arabic, start=2]
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. *Update FORGET* (no individual frees, just rewind):
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[source,c]
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----
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/* Instead of free(e) loop, rewind allocator */
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size_t target_offset = (uint8_t*)target - vm->memory;
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vm->dict_headers_used = target_offset;
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----
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[arabic, start=3]
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. *Adjust VM Initialization*:
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[source,c]
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----
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vm->dict_headers_used = 0; /* Headers start at memory[0] */
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vm->here = DICT_HEADERS_MAX; /* User data starts at 256KB */
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----
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[arabic, start=4]
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. *No Changes to Fast-Lookup Cache*: Cache buckets still use malloc for
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the pointer arrays, but entries themselves are in VM memory.
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==== Testing Strategy:
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[source,bash]
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----
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# Test with standard malloc (current):
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make clean && make test
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# Test with VM-based allocation:
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make clean
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CFLAGS="-DSTARFORTH_VM_DICT_ALLOC" make test
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# Test L4Re minimal build:
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make clean
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CFLAGS="-DSTARFORTH_MINIMAL -DSTARFORTH_VM_DICT_ALLOC" make rpi4-cross
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----
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=== Current Status
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*Decision*: Keep using `+malloc()+` for now, document the abstraction
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point clearly.
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*Rationale*:
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* Current implementation is stable and well-tested
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* L4Re port can implement the switch when needed
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* Abstraction layer is simple and well-defined
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* No performance difference between approaches
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*Action Items for L4Re Port*:
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[arabic]
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. Define `+STARFORTH_VM_DICT_ALLOC+` in L4Re build
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. Implement `+dict_alloc_from_vm()+` function
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. Update `+FORGET+` to use rewind instead of free loop
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. Test with full test suite
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. Verify no memory leaks in microkernel environment
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=== Minimal Code Changes Needed
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The switch to VM-based allocation requires changes to only 3 functions:
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[arabic]
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. *`+vm_create_word()+`* - Use `+dict_alloc_from_vm()+` instead of
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`+malloc()+`
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. *`+dictionary_word_forget()+`* - Rewind `+dict_headers_used+` instead
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of `+free()+` loop
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. *`+vm_init()+`* - Initialize `+dict_headers_used+` and offset `+HERE+`
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Add to `+VM+` struct in `+include/vm.h+`:
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[source,c]
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----
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size_t dict_headers_used; /* Bytes used for dictionary headers (VM mode only) */
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----
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*Estimated effort*: 4 hours to implement + 2 hours testing = *6 hours
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total*
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=== References
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* Current malloc usage: `+src/dictionary_management.c:228+`
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* Current free usage: `+src/word_source/defining_words.c:554+`
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* Fast-lookup cache: `+src/dictionary_management.c:43-67+` (unchanged)
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* L4Re dataspace docs: `+docs/L4RE_INTEGRATION.md+`
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'''''
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*Author*: R. A. James *Date*: 2025-10-01 *Status*: Documented,
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implementation deferred to L4Re port
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