Eremey Valetov
f207d74aec
Four roadmap items: - codegen: fix parenthesized string comparison. emit_atom didn't consume the body of a string-literal token (`"`), so for PRINT (A$+B$ < "ZZZ") it emitted a 0 placeholder, advanced one byte, and left "ZZZ" to be reparsed as a variable + extra trailing tokens -- the binary then failed to link with `var_ZZ_sng` undeclared. emit_atom now skips to the closing quote. Separately, the left_type tracking in emit_num_prec dropped VT_STR after a string + string concat (becoming VT_SNG), so the string-comparison codepath skipped when the relational operator arrived. Preserve VT_STR through TOK_PLUS when both operands are strings. Verified: paren string-cmp now compiles and produces the same -1 / 0 result as the interpreter. - compiler: --no-gc-check and --fast-math optimization flags. --no-gc-check skips the per-line gwrt_check_line() (no string-pool GC, no Ctrl+Break trap). --fast-math drops the divide-by-zero guard on `/`; the divisor still goes through (double) so 10/0 produces inf rather than SIGFPE. Both threaded through codegen_opts_t and exposed in --help. --inline-arrays from the roadmap deferred -- larger refactor. - interp: raise static caps on 32-bit / Linux builds. vars 256 -> 1024, arrays 64 -> 256, MAX_FOR_DEPTH 16 -> 64, MAX_GOSUB_DEPTH 24 -> 128, MAX_WHILE_DEPTH 16 -> 64. Codegen FOR_STACK_MAX 16 -> 64. Analysis-pass caps: MAX_LINES 4096 -> 8192, MAX_VARS 256 -> 1024, MAX_GOTOS 256 -> 1024, MAX_DATA 1024 -> 4096, MAX_GOSUB_RET 256 -> 1024. 16-bit DOS keeps the original modest caps via #ifdef _M_I86 -- the MEDIUM model has a single 64KB DGROUP for all static data and the bumped sizes broke runtime startup under DOSBox-X. 16-bit binary grew from 128KB to 132KB from the offset_secs field plus DATE$/TIME$ shift code, well within the FreeDOS budget. - interp + codegen: DATE$ / TIME$ assignment via process-local clock offset. Was a no-op accept-and-ignore. Now sets gw.time_offset_secs (long), and DATE$ / TIME$ / TIMER readers apply it to time(NULL) before formatting. The OS clock is unaffected (would need root). Compiled-binary readers also reference gw.time_offset_secs since libgwrt shares the gw struct. Verified: PRINT DATE$; DATE$="12-31-1999"; PRINT DATE$ shows the expected before/after in both interpreter and AOT paths. After these changes: 72/72 interpreter tests, 68/68 compat, 63/63 compiler tests, DOS smoke under DOSBox-X all pass. Build clean on both Linux (cmake) and 16-bit DOS (build_dos.sh 16).
124 lines
5.6 KiB
Markdown
124 lines
5.6 KiB
Markdown
# Roadmap
|
|
|
|
## Completed
|
|
|
|
### Ahead-of-Time Compiler (v0.16.0)
|
|
|
|
`gwbasic-compile` translates tokenized .bas programs to C source, then
|
|
invokes GCC to produce native executables linked against `libgwrt.a`.
|
|
|
|
Pipeline: `.bas` → `gw_crunch()` → analysis pass → C codegen → `gcc` → native binary.
|
|
|
|
**63 of 63 eligible tests pass (100%)** via `tests/run_compiler_tests.sh`.
|
|
The harness only skips hardware-dependent tests (graphics/sound/timer)
|
|
and CHAIN/RUN target files that aren't standalone. The compiler now
|
|
accepts unnumbered direct-mode programs by auto-numbering them.
|
|
|
|
Language coverage:
|
|
|
|
- All statements: PRINT, LET, IF/THEN/ELSE, GOTO, GOSUB/RETURN, FOR/NEXT,
|
|
WHILE/WEND, ON GOTO/GOSUB, ON ERROR GOTO, RESUME/RESUME NEXT, DIM, DEF FN,
|
|
SWAP, READ/DATA/RESTORE, INPUT/LINE INPUT, OPEN/CLOSE/PRINT#/INPUT#/WRITE#,
|
|
FIELD/LSET/RSET/GET/PUT, BSAVE/BLOAD, SAVE/LOAD, CHAIN/COMMON, SCREEN,
|
|
PSET/PRESET, COLOR/LOCATE/CLS, CIRCLE/DRAW/PAINT/PLAY, VIEW/WINDOW/PALETTE,
|
|
POKE/OUT/WAIT, DEF SEG, RANDOMIZE, CLEAR, MID$ assignment, ERROR,
|
|
KILL/NAME/FILES/SHELL/MKDIR/CHDIR/RMDIR, ENVIRON, LPRINT/LLIST, WIDTH, KEY
|
|
- All operators: `+` `-` `*` `/` `\` `MOD` `^` `AND` `OR` `XOR` `NOT` `EQV` `IMP`
|
|
`>` `<` `=` `<=` `>=` `<>` (including string comparison via strcmp)
|
|
- All functions: math, string, file, conversion (CVI/CVS/CVD/MKI$/MKS$/MKD$),
|
|
graphics (POINT/PMAP), system (FRE/ERR/ERL/TIMER/DATE$/TIME$/ENVIRON$/INKEY$)
|
|
- Token embedding for complex statements (PRINT USING, DEF FN, graphics,
|
|
file I/O, MID$ assignment) with selective variable sync
|
|
- Division-by-zero detection, RNG matching (gw_rnd), ON ERROR GOTO via
|
|
setjmp/longjmp
|
|
|
|
Optimizations:
|
|
|
|
- Constant folding (compile-time arithmetic on literals)
|
|
- Dead code elimination (skip statements after GOTO/END/STOP)
|
|
- FOR step=1 elision (var++ instead of step variable, simple comparison)
|
|
- Fast-path expression emitter (skip buffering for common case)
|
|
- Selective variable sync in delegated statements
|
|
- REM-line skip (no runtime check for comment-only lines)
|
|
|
|
### Hardware I/O Simulator (v0.15.0)
|
|
|
|
Implemented in `portio.c` / `portio.h` following the `virmem.c` dispatch
|
|
pattern. Emulates 8253 PIT channel 2 (speaker frequency), PPI port B
|
|
(speaker on/off with continuous tone via PulseAudio), CGA mode/color
|
|
registers, game port (joystick stub), and COM1 serial (transmitter-ready
|
|
stub). Default: reads return 0xFF (floating bus), writes discarded.
|
|
|
|
Also in v0.15.0: 100% token coverage (all 144 GW-BASIC tokens handled),
|
|
string space pool with compacting garbage collector, RESET, ENVIRON/ENVIRON$,
|
|
ERDEV/ERDEV$, IOCTL/IOCTL$, LCOPY, DATE$/TIME$ assignment, CALL, COM.
|
|
|
|
### Jupyter Kernel (v0.15.0)
|
|
|
|
`gwbasickernel/` -- Jupyter notebook kernel using the persistent subprocess
|
|
model with sentinel protocol.
|
|
|
|
- **Inline Sixel graphics** -- pure-Python Sixel decoder renders SCREEN
|
|
commands as inline PNG images in the notebook
|
|
- **INPUT statement support** via Jupyter stdin protocol
|
|
- **Pygments syntax highlighting** for code cells
|
|
- **Tab completion** for all GW-BASIC keywords
|
|
- **Magic commands**: `%reset`, `%timeout`, `%new`
|
|
|
|
Install: `pip install -e . && gwbasickernel-install --user`
|
|
|
|
### Compiler Memory Safety (v0.17.0)
|
|
|
|
`--warn`, `--safe`, and `--safe=sanitize` flags for the ahead-of-time compiler.
|
|
|
|
- **`--warn`** -- static analysis: uninitialized variables, GOTO to nonexistent
|
|
line, unreachable code detection. Zero runtime cost.
|
|
- **`--safe`** (implies `--warn`) -- checked integer arithmetic via
|
|
`gw_int_add/sub/mul/neg` (raises Overflow instead of wrapping), enhanced
|
|
array bounds diagnostics with variable names and line numbers, GOSUB stack
|
|
overflow diagnostics, ABS/SGN type-preserving codegen, string pool GC pinning
|
|
infrastructure
|
|
- **`--safe=sanitize`** -- above plus `-fsanitize=address,undefined` passed to gcc
|
|
|
|
### DOS / FreeDOS Target (v0.17.0)
|
|
|
|
Cross-compiles to DOS using OpenWatcom V2. Two targets:
|
|
|
|
- **16-bit real-mode** (`Makefile.dos16`): 128KB standalone MZ executable,
|
|
MEDIUM memory model, far-heap TUI screen buffer, no DOS extender required
|
|
- **32-bit DOS/4GW** (`Makefile.dos`): 175KB LE executable, flat memory model,
|
|
requires DOS4GW.EXE extender
|
|
|
|
Tested on FreeDOS 1.4 via QEMU.
|
|
|
|
## Next Up
|
|
|
|
### Compiler Optimization Flags
|
|
- **`--no-gc-check`** -- skip `gwrt_check_line()` per-line calls (no string pool
|
|
GC, no Ctrl+Break check) for maximum throughput
|
|
- **`--inline-arrays`** -- emit direct array indexing for statically-DIMmed arrays
|
|
instead of runtime `gwrt_array_elem()` lookup
|
|
- **`--fast-math`** -- skip division-by-zero checks, allow unsafe float ops
|
|
- **`-O0` through `-O3`** -- compiler-level optimization tiers mapping to different
|
|
sets of codegen optimizations (constant folding, dead code elimination, FOR
|
|
step=1 elision, fast-path expressions)
|
|
|
|
### IDE Integration
|
|
- **VS Code extension** -- syntax highlighting (TextMate grammar), snippets,
|
|
run/debug tasks, integrated terminal runner
|
|
- **JetBrains plugin (IntelliJ/CLion)** -- syntax highlighting, code completion,
|
|
run configurations, debugger integration (breakpoints via `STOP`, variable
|
|
inspection), structure view (line number outline)
|
|
|
|
## Known Limitations
|
|
|
|
- Static caps -- 32-bit / Linux builds: 1024 variables, 256 arrays,
|
|
64 FOR nesting, 128 GOSUB nesting, 64 WHILE nesting. 16-bit real-mode
|
|
DOS keeps the original modest caps (256 / 64 / 16 / 24 / 16) because
|
|
the MEDIUM model has a single 64KB DGROUP for all static data.
|
|
- `CALL`/`CALLS` (machine code execution) raises Illegal function call
|
|
- `DATE$`/`TIME$` assignment shifts the program's view of the clock via
|
|
a process-local offset; the OS time is unaffected (setting the OS
|
|
clock would require root)
|
|
- Device stubs (`ERDEV`, `IOCTL`, `COM`, `LCOPY`) return defaults
|