diff options
| -rw-r--r-- | vm.c | 35 |
1 files changed, 18 insertions, 17 deletions
@@ -36,17 +36,19 @@ int runvm(State *S) { #define RBYTE() (ch->bc.d[th->ip++]) #define RSHORT() (th->ip += 2, (uint16_t)( ch->bc.d[th->ip-2] | ch->bc.d[th->ip-1] << 8 )) -#define PUSH(v) th->stack[th->fp + th->sp++] = v; -#define POP() (th->stack[th->fp + --th->sp]) -#define PEEK() (th->stack[th->fp + th->sp-1]) +#define PUSH(v) th->stack[th->sp++] = v; +#define POP() (th->stack[--th->sp]) +#define PEEK() (th->stack[th->sp-1]) +// 1 is TOS +#define PEEKN(n) (th->stack[th->sp-n]) while (1) { ch = th->ch; if (S->do_trace) { - printf("\t[%lu + %lu] : ",th->fp, th->sp); - for (int i = 0; i < th->sp; i++) { + printf("\t[%lu -> %lu] : ",th->fp, th->sp); + for (int i = th->fp; i < th->sp; i++) { printf("(%d) ",i); - print_val(th->stack[th->fp + i]); + print_val(th->stack[i]); printf(" ; "); } printf("\n%p ",(void *)ch); @@ -178,25 +180,25 @@ int runvm(State *S) { case OP_FALSE: PUSH(VAL_FALSE); break; case OP_CALL: { + // nargs + 1 = function and args uint8_t len = RBYTE(); - th->sp -= len-1; - Val callee = POP(); + Val callee = PEEKN(len); if (!IS_FUNC(callee)) { - fprintf(stderr, "can only call functions\n"); - goto done; + fprintf(stderr,"can only call functions"); + exit(1); } ObjFunc *func = AS_FUNC(callee); StackFrame *sf = &th->rstack[th->rsp++]; - sf->ch = th->ch; sf->ip = th->ip; + sf->ch = th->ch; sf->fp = th->fp; - th->ch = &func->ch; th->ip = 0; - th->fp = th->sp; - th->sp = len; + th->ch = &func->ch; + th->fp = th->sp - len; + break; } @@ -210,11 +212,10 @@ int runvm(State *S) { case OP_RET: { StackFrame *sf = &th->rstack[--th->rsp]; - size_t orig_fp = th->fp; - th->ch = sf->ch; + th->ip = sf->ip; + th->ch = sf->ch; th->fp = sf->fp; - th->sp += (orig_fp - th->fp); break; } case OP_HALT: |