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#include <stddef.h>
#include <stdint.h>
#include <stdlib.h>
#include <stdbool.h>
#include <stdio.h>
#include "val.h"
#include "vm.h"
void *M(void *p, size_t sz) {
if (sz == 0) {
free(p);
return NULL;
} else {
return realloc(p, sz);
}
}
Chunk chunk_new() {
return (Chunk){
.blen = 0, .bcap = 0, .b = NULL,
.clen = 0, .ccap = 0, .c = NULL,
};
}
size_t chunk_wbc(Chunk *ch, uint8_t byte) {
if (ch->blen == ch->bcap) {
size_t newsz = (ch->bcap == 0 ? 8 : ch->bcap * 2);
ch->b = M(ch->b, newsz * sizeof(uint8_t));
ch->bcap = newsz;
}
size_t ix = ch->blen;
ch->b[ix] = byte;
ch->blen ++;
return ix;
}
size_t chunk_wconst(Chunk *ch, Val v) {
if (ch->clen == ch->ccap) {
size_t newsz = (ch->ccap == 0 ? 8 : ch->ccap *2);
ch->c = M(ch->c, newsz * sizeof(Val));
ch->ccap = newsz;
}
size_t ix = ch->clen;
ch->c[ix] = v;
ch->clen ++;
return ix;
}
Vm vm_new(Chunk *ch) {
Vm vm = (Vm){
.ch = ch,
.ip = 0,
.sp = 0
};
for (int i = 0; i < STACKSIZE; i++) {
vm.stack[i] = VAL_NIL;
}
return vm;
}
static void runvm() {
Chunk ch = chunk_new();
chunk_wbc(&ch, OP_LOADK);
chunk_wbc(&ch, 1);
chunk_wbc(&ch, OP_PRINT);
chunk_wbc(&ch, OP_LOADK);
chunk_wbc(&ch, 2);
chunk_wbc(&ch, OP_LOADK);
chunk_wbc(&ch, 0);
chunk_wbc(&ch, OP_RET);
chunk_wconst(&ch, VAL_BOOL(false));
chunk_wconst(&ch, VAL_NIL);
chunk_wconst(&ch, VAL_NUM(420.69));
Vm vm = vm_new(&ch);
#define RBYTE() (vm.ch->b[vm.ip++])
while (1) {
uint8_t instr = RBYTE();
switch (instr) {
case OP_RET:
printf("done!\n");
goto done;
break;
case OP_LOADK:
uint8_t cix = RBYTE();
Val v = vm.ch->c[cix];
print_val(v);
break;
case OP_PRINT:
printf("print\n");
break;
}
}
done:;
}
int main() { runvm(); }
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