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mirror of https://github.com/hsoft/collapseos.git synced 2024-12-25 04:58:05 +11:00

Add a C implementation of native words

This will soon replace the libz80 based "forth" and
"stage" executables. This is much, much faster.
This commit is contained in:
Virgil Dupras 2020-06-26 15:50:13 -04:00
parent e8f1464ae5
commit 36cb1389e6
5 changed files with 602 additions and 0 deletions

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@ -39,6 +39,8 @@ it's not a z80 emulator, but a *javascript port of Collapse OS*!
* `blk`: Collapse OS filesystem's content. That's actually where Collapse OS'
source code is located. Everything else is peripheral.
* `cvm`: A C implementation of Collapse OS, allowing it to run natively on any
POSIX platform.
* `recipes`: collection of recipes that assemble Collapse OS on a specific
machine.
* `tools`: Tools for working with Collapse OS from "modern" environments. For

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cvm/Makefile Normal file
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TARGETS = forth
OBJS = vm.o
BLKPACK = ../tools/blkpack
BLKUNPACK = ../tools/blkunpack
.PHONY: all
all: $(TARGETS)
$(BLKPACK):
$(MAKE) -C ../tools
.PHONY: $(BLKUNPACK)
$(BLKUNPACK): $(BLKPACK)
stage: stage.c $(OBJS) blkfs
$(CC) stage.c $(OBJS) -o $@
blkfs: $(BLKPACK)
$(BLKPACK) ../blk > $@
forth: forth.c $(OBJS) blkfs
$(CC) forth.c $(OBJS) -lncurses -o $@
vm.o: vm.c
$(CC) -DFBIN_PATH=\"`pwd`/forth.bin\" -DBLKFS_PATH=\"`pwd`/blkfs\" -c -o vm.o vm.c
.PHONY: updatebootstrap
updatebootstrap: stage xcomp.fs pack
./stage < xcomp.fs > new.bin
mv new.bin forth.bin
.PHONY: pack
pack:
rm blkfs && $(MAKE) blkfs
.PHONY: unpack
unpack:
$(BLKUNPACK) ../blk < blkfs
.PHONY: clean
clean:
rm -f $(TARGETS) *.o blkfs

119
cvm/forth.c Normal file
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#include <stdint.h>
#include <stdio.h>
#include <unistd.h>
#include <curses.h>
#include <termios.h>
#include "vm.h"
#define WCOLS 80
#define WLINES 32
#define STDIO_PORT 0x00
// This binary is also used for automated tests and those tests, when
// failing, send a non-zero value to RET_PORT to indicate failure
#define RET_PORT 0x01
#define SETX_PORT 0x05
#define SETY_PORT 0x06
static FILE *fp;
static int retcode = 0;
WINDOW *bw, *dw, *w;
void debug_panel()
{
char buf[30];
VM_debugstr(buf);
mvwaddnstr(dw, 0, 0, buf, 30);
wrefresh(dw);
}
static uint8_t iord_stdio()
{
int c;
if (fp != NULL) {
c = getc(fp);
} else {
debug_panel();
c = wgetch(w);
}
if (c == EOF) {
c = 4; // ASCII EOT
}
return (uint8_t)c;
}
static void iowr_stdio(uint8_t val)
{
if (fp != NULL) {
putchar(val);
} else {
if (val >= 0x20 || val == '\n') {
wechochar(w, val);
} else if (val == 0x08) {
int y, x; getyx(w, y, x);
wmove(w, y, x-1);
}
}
}
static void iowr_ret(uint8_t val)
{
retcode = val;
}
static void iowr_setx(uint8_t val)
{
int y, x; getyx(w, y, x);
wmove(w, y, val);
}
static void iowr_sety(uint8_t val)
{
int y, x; getyx(w, y, x);
wmove(w, val, x);
}
int main(int argc, char *argv[])
{
VM *vm = VM_init();
if (!vm) {
return 1;
}
vm->iord[STDIO_PORT] = iord_stdio;
vm->iowr[STDIO_PORT] = iowr_stdio;
vm->iowr[RET_PORT] = iowr_ret;
vm->iowr[SETX_PORT] = iowr_setx;
vm->iowr[SETY_PORT] = iowr_sety;
w = NULL;
if (argc == 2) {
fp = fopen(argv[1], "r");
if (fp == NULL) {
fprintf(stderr, "Can't open %s\n", argv[1]);
return 1;
}
while (VM_steps(1000));
fclose(fp);
} else if (argc == 1) {
fp = NULL;
initscr(); cbreak(); noecho(); nl(); clear();
// border window
bw = newwin(WLINES+2, WCOLS+2, 0, 0);
wborder(bw, 0, 0, 0, 0, 0, 0, 0, 0);
wrefresh(bw);
// debug panel
dw = newwin(1, 30, LINES-1, COLS-30);
w = newwin(WLINES, WCOLS, 1, 1);
scrollok(w, 1);
while (VM_steps(1000)) {
debug_panel();
}
nocbreak(); echo(); delwin(w); delwin(bw); delwin(dw); endwin();
printf("\nDone!\n");
fprintf(stderr, "Done!\n");
VM_printdbg();
} else {
fprintf(stderr, "Usage: ./forth [filename]\n");
retcode = 1;
}
VM_deinit();
return 0;
}

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cvm/vm.c Normal file
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#include <stdio.h>
#include <string.h>
#include "vm.h"
// Port for block reads. Each read or write has to be done in 5 IO writes:
// 1 - r/w. 1 for read, 2 for write.
// 2 - blkid MSB
// 3 - blkid LSB
// 4 - dest addr MSB
// 5 - dest addr LSB
#define BLK_PORT 0x03
#ifndef BLKFS_PATH
#error BLKFS_PATH needed
#endif
#ifndef FBIN_PATH
#error FBIN_PATH needed
#endif
static VM vm;
static uint64_t blkop = 0; // 5 bytes
static FILE *blkfp;
static byte io_read(word addr)
{
addr &= 0xff;
IORD fn = vm.iord[addr];
if (fn != NULL) {
return fn();
} else {
fprintf(stderr, "Out of bounds I/O read: %d\n", addr);
return 0;
}
}
static void io_write(word addr, byte val)
{
addr &= 0xff;
IOWR fn = vm.iowr[addr];
if (fn != NULL) {
fn(val);
} else {
fprintf(stderr, "Out of bounds I/O write: %d / %d (0x%x)\n", addr, val, val);
}
}
static void iowr_blk(byte val)
{
blkop <<= 8;
blkop |= val;
byte rw = blkop >> 32;
if (rw) {
word blkid = (blkop >> 16);
word dest = blkop & 0xffff;
blkop = 0;
fseek(blkfp, blkid*1024, SEEK_SET);
if (rw==2) { // write
fwrite(&vm.mem[dest], 1024, 1, blkfp);
} else { // read
fread(&vm.mem[dest], 1024, 1, blkfp);
}
}
}
static word gw(word addr) { return vm.mem[addr+1] << 8 | vm.mem[addr]; }
static void sw(word addr, word val) {
vm.mem[addr] = val;
vm.mem[addr+1] = val >> 8;
}
static word pop() { return vm.mem[vm.SP++] | vm.mem[vm.SP++] << 8; }
static void push(word x) {
vm.SP -= 2; sw(vm.SP, x);
if (vm.SP < vm.minSP) { vm.minSP = vm.SP; }
}
static word popRS() { word x = gw(vm.RS); vm.RS -= 2; return x; }
static void pushRS(word val) {
vm.RS += 2; sw(vm.RS, val);
if (vm.RS > vm.maxRS) { vm.maxRS = vm.RS; }
}
static void execute(word wordref) {
byte wtype = vm.mem[wordref];
if (wtype == 0) { // native
vm.nativew[vm.mem[wordref+1]]();
} else if (wtype == 1) { // compiled
pushRS(vm.IP);
vm.IP = wordref+1;
} else { // cell or does
push(wordref+1);
if (wtype == 4) {
vm.IP = gw(wordref+3);
}
}
}
static word find(word daddr, word waddr) {
byte len = vm.mem[waddr];
while (1) {
if ((vm.mem[daddr-1] & 0x7f) == len) {
if (strncmp(&vm.mem[waddr+1], &vm.mem[daddr-3-len], len) == 0) {
return daddr;
}
}
daddr -= 3;
word offset = gw(daddr);
if (offset) {
daddr -= offset;
} else {
return 0;
}
}
}
static void EXIT() { vm.IP = popRS(); }
static void _br_() { vm.IP += gw(vm.IP); };
static void _cbr_() { if (!pop()) { _br_(); } else { vm.IP += 2; } };
static void _loop_() {
word I = gw(vm.RS); I++; sw(vm.RS, I);
if (I == gw(vm.RS-2)) { // don't branch
popRS(); popRS();
vm.IP += 2;
} else { // branch
_br_();
}
}
static void SP_to_R_2() { word x = pop(); pushRS(pop()); pushRS(x); }
static void nlit() { push(gw(vm.IP)); vm.IP += 2; }
static void slit() { push(vm.IP); vm.IP += vm.mem[vm.IP] + 1; }
static void SP_to_R() { pushRS(pop()); }
static void R_to_SP() { push(popRS()); }
static void R_to_SP_2() { word x = popRS(); push(popRS()); push(x); }
static void EXECUTE() { execute(pop()); }
static void ROT() { // a b c -- b c a
word c = pop(); word b = pop(); word a = pop();
push(b); push(c); push(a);
}
static void DUP() { // a -- a a
word a = pop(); push(a); push(a);
}
static void CDUP() {
word a = pop(); push(a); if (a) { push(a); }
}
static void DROP() { pop(); }
static void SWAP() { // a b -- b a
word b = pop(); word a = pop();
push(b); push(a);
}
static void OVER() { // a b -- a b a
word b = pop(); word a = pop();
push(a); push(b); push(a);
}
static void PICK() {
word x = pop();
push(gw(vm.SP+x*2));
}
static void _roll_() { // "1 2 3 4 4 (roll)" --> "1 3 4 4"
word x = pop();
while (x) { vm.mem[vm.SP+x+2] = vm.mem[vm.SP+x]; x--; }
}
static void DROP2() { pop(); pop(); }
static void DUP2() { // a b -- a b a b
word b = pop(); word a = pop();
push(a); push(b); push(a); push(b);
}
static void S0() { push(SP_ADDR); }
static void Saddr() { push(vm.SP); }
static void AND() { push(pop() & pop()); }
static void OR() { push(pop() | pop()); }
static void XOR() { push(pop() ^ pop()); }
static void NOT() { push(!pop()); }
static void PLUS() { push(pop() + pop()); }
static void MINUS() {
word b = pop(); word a = pop();
push(a - b);
}
static void MULT() { push(pop() * pop()); }
static void DIVMOD() {
word b = pop(); word a = pop();
push(a % b); push(a / b);
}
static void STORE() {
word a = pop(); word val = pop();
sw(a, val);
}
static void FETCH() { push(gw(pop())); }
static void CSTORE() {
word a = pop(); word val = pop();
vm.mem[a] = val;
}
static void CFETCH() { push(vm.mem[pop()]); }
static void IO_OUT() {
word a = pop(); word val = pop();
io_write(a, val);
}
static void IO_IN() { push(io_read(pop())); }
static void RI() { push(gw(vm.RS)); }
static void RI_() { push(gw(vm.RS-2)); }
static void RJ() { push(gw(vm.RS-4)); }
static void BYE() { vm.running = false; }
static void _resSP_() { vm.SP = SP_ADDR; }
static void _resRS_() { vm.RS = RS_ADDR; }
static void Seq() {
word s1 = pop(); word s2 = pop();
byte len = vm.mem[s1];
if (len == vm.mem[s2]) {
s1++; s2++;
push(strncmp(&vm.mem[s1], &vm.mem[s2], len) == 0);
} else {
push(0);
}
}
static void CMP() {
word b = pop(); word a = pop();
if (a == b) { push(0); } else if (a > b) { push(1); } else { push(-1); }
}
static void _find() {
word waddr = pop(); word daddr = pop();
daddr = find(daddr, waddr);
if (daddr) {
push(daddr); push(1);
} else {
push(waddr); push(0);
}
}
static void ZERO() { push(0); }
static void ONE() { push(1); }
static void MONE() { push(-1); }
static void PLUS1() { push(pop()+1); }
static void MINUS1() { push(pop()-1); }
static void MINUS2() { push(pop()-2); }
static void PLUS2() { push(pop()+2); }
static void RSHIFT() { word u = pop(); push(pop()>>u); }
static void LSHIFT() { word u = pop(); push(pop()<<u); }
// create a native word with a specific target offset. target is addr of
// wordref.
static void create_native_t(word target, char *name, NativeWord func) {
int len = strlen(name);
strcpy(&vm.mem[target-len-3], name);
word prev_off = target - 3 - vm.xcurrent;
sw(target-3, prev_off);
vm.mem[target-1] = len;
vm.mem[target] = 0; // native word type
vm.mem[target+1] = vm.nativew_count;
vm.nativew[vm.nativew_count++] = func;
vm.xcurrent = target;
}
/* INITIAL BOOTSTRAP PLAN
For the initial bootstrap of the C VM, we treat every native word as a stable
word, giving it exactly the same memory offset as we have in the z80 forth.bin.
This will greatly simplify the initial bootstrap because we'll be able to
directly plug the "core words" part of forth.bin into our C VM and run it.
Once we have that, we can de-stabilize the native words that aren't part of the
stable ABI and bootstrap ourselves from ourselves. Good plan, right?
*/
VM* VM_init() {
fprintf(stderr, "Using blkfs %s\n", BLKFS_PATH);
blkfp = fopen(BLKFS_PATH, "r+");
if (!blkfp) {
fprintf(stderr, "Can't open\n");
return NULL;
}
fseek(blkfp, 0, SEEK_END);
if (ftell(blkfp) < 100 * 1024) {
fclose(blkfp);
fprintf(stderr, "emul/blkfs too small, something's wrong, aborting.\n");
return NULL;
}
fseek(blkfp, 0, SEEK_SET);
// initialize memory
memset(vm.mem, 0, 0x10000);
FILE *bfp = fopen(FBIN_PATH, "r");
if (!bfp) {
fprintf(stderr, "Can't open forth.bin\n");
return NULL;
}
int i = 0;
int c = getc(bfp);
while (c != EOF) {
vm.mem[i++] = c;
c = getc(bfp);
}
fclose(bfp);
vm.SP = SP_ADDR;
vm.RS = RS_ADDR;
vm.minSP = SP_ADDR;
vm.maxRS = RS_ADDR;
vm.nativew_count = 0;
for (int i=0; i<0x100; i++) {
vm.iord[i] = NULL;
vm.iowr[i] = NULL;
}
vm.iowr[BLK_PORT] = iowr_blk;
vm.xcurrent = 0x3f; // make EXIT's prev field 0
create_native_t(0x42, "EXIT", EXIT);
create_native_t(0x53, "(br)", _br_);
create_native_t(0x67, "(?br)", _cbr_);
create_native_t(0x80, "(loop)", _loop_);
create_native_t(0xa9, "2>R", SP_to_R_2);
create_native_t(0xbf, "(n)", nlit);
create_native_t(0xd4, "(s)", slit);
// End of stable ABI
create_native_t(0xe7, ">R", SP_to_R);
create_native_t(0xf4, "R>", R_to_SP);
create_native_t(0x102, "2R>", R_to_SP_2);
create_native_t(0x1d4, "EXECUTE", EXECUTE);
create_native_t(0x1e1, "ROT", ROT);
create_native_t(0x1f4, "DUP", DUP);
create_native_t(0x205, "?DUP", CDUP);
create_native_t(0x21a, "DROP", DROP);
create_native_t(0x226, "SWAP", SWAP);
create_native_t(0x238, "OVER", OVER);
create_native_t(0x24b, "PICK", PICK);
create_native_t(0x26c, "(roll)", _roll_);
create_native_t(0x283, "2DROP", DROP2);
create_native_t(0x290, "2DUP", DUP2);
create_native_t(0x2a2, "S0", S0);
create_native_t(0x2af, "'S", Saddr);
create_native_t(0x2be, "AND", AND);
create_native_t(0x2d3, "OR", OR);
create_native_t(0x2e9, "XOR", XOR);
create_native_t(0x2ff, "NOT", NOT);
create_native_t(0x314, "+", PLUS);
create_native_t(0x323, "-", MINUS);
create_native_t(0x334, "*", MULT);
create_native_t(0x358, "/MOD", DIVMOD);
create_native_t(0x37c, "!", STORE);
create_native_t(0x389, "@", FETCH);
create_native_t(0x39a, "C!", CSTORE);
create_native_t(0x3a6, "C@", CFETCH);
create_native_t(0x3b8, "PC!", IO_OUT);
create_native_t(0x3c6, "PC@", IO_IN);
create_native_t(0x3d7, "I", RI);
create_native_t(0x3e7, "I'", RI_);
create_native_t(0x3f6, "J", RJ);
create_native_t(0x407, "BYE", BYE);
create_native_t(0x416, "(resSP)", _resSP_);
create_native_t(0x427, "(resRS)", _resRS_);
create_native_t(0x434, "S=", Seq);
create_native_t(0x457, "CMP", CMP);
create_native_t(0x476, "_find", _find);
create_native_t(0x4a4, "0", ZERO);
create_native_t(0x4b0, "1", ONE);
create_native_t(0x4bd, "-1", MONE);
create_native_t(0x4ca, "1+", PLUS1);
create_native_t(0x4d9, "1-", MINUS1);
create_native_t(0x4e8, "2+", PLUS2);
create_native_t(0x4f8, "2-", MINUS2);
create_native_t(0x50c, "RSHIFT", RSHIFT);
create_native_t(0x52a, "LSHIFT", LSHIFT);
vm.IP = gw(0x04) + 1; // BOOT
sw(SYSVARS+0x02, gw(0x08)); // CURRENT
sw(SYSVARS+0x04, gw(0x08)); // HERE
vm.running = true;
return &vm;
}
void VM_deinit()
{
fclose(blkfp);
}
bool VM_steps(int n) {
if (!vm.running) {
fprintf(stderr, "machine halted!\n");
return false;
}
while (n && vm.running) {
word wordref = gw(vm.IP);
vm.IP += 2;
execute(wordref);
n--;
}
return vm.running;
}
void VM_memdump() {
fprintf(stderr, "Dumping memory to memdump. IP %04x\n", vm.IP);
FILE *fp = fopen("memdump", "w");
fwrite(vm.mem, 0x10000, 1, fp);
fclose(fp);
}
void VM_debugstr(char *s) {
sprintf(s, "SP %04x (%04x) RS %04x (%04x)",
vm.SP, vm.minSP, vm.RS, vm.maxRS);
}
void VM_printdbg() {
char buf[0x100];
VM_debugstr(buf);
fprintf(stderr, "%s\n", buf);
}

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cvm/vm.h Normal file
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#include <stdint.h>
#include <stdbool.h>
#define SP_ADDR 0xffff
#define RS_ADDR 0xff00
#define SYSVARS 0xe800
typedef uint8_t byte;
typedef uint16_t word;
// Native words in this C Forth VMs are indexed in an array. The word in memory
// is the typical 0x00 to indicate native, followed by an index byte. The
// Execute routine will then know which native word to execute.
typedef void (*NativeWord) ();
typedef byte (*IORD) ();
typedef void (*IOWR) (byte data);
/* Native word placement
Being a C VM, all actual native code is outside the VM's memory. However,
we have a stable ABI to conform to. VM_init() configures the memory by
placing references to stable words at proper offsets, and then add all other
native words next to it. This will result in a "boot binary" that is much
more compact than a real Collapse OS memory layout.
*/
typedef struct {
byte mem[0x10000];
word SP;
word RS;
word IP;
NativeWord nativew[0x100];
byte nativew_count;
// Array of 0x100 function pointers to IO read and write routines. Leave to
// NULL when IO port is unhandled.
IORD iord[0x100];
IOWR iowr[0x100];
word xcurrent; // only used during native bootstrap
word maxRS;
word minSP;
bool running;
} VM;
VM* VM_init();
void VM_deinit();
bool VM_steps(int n);
void VM_memdump();
void VM_debugstr(char *s);
void VM_printdbg();