#include "ao_lisp.h"
-#if 0
-#define DBG(...) printf(__VA_ARGS__)
+#if 1
+static int stack_depth;
+#define DBG_INDENT() do { int _s; for(_s = 0; _s < stack_depth; _s++) printf(" "); } while(0)
+#define DBG_IN() (++stack_depth)
+#define DBG_OUT() (--stack_depth)
+#define DBG(...) printf(__VA_ARGS__)
+#define DBGI(...) do { DBG_INDENT(); DBG(__VA_ARGS__); } while (0)
#define DBG_CONS(a) ao_lisp_cons_print(ao_lisp_cons_poly(a))
#define DBG_POLY(a) ao_lisp_poly_print(a)
#define OFFSET(a) ((a) ? (int) ((uint8_t *) a - ao_lisp_pool) : -1)
#else
+#define DBG_INDENT()
+#define DBG_IN()
+#define DBG_OUT()
#define DBG(...)
+#define DBGI(...)
#define DBG_CONS(a)
#define DBG_POLY(a)
#endif
+enum eval_state {
+ eval_sexpr,
+ eval_val,
+ eval_exec,
+ eval_exec_direct
+};
+
struct ao_lisp_stack {
- ao_poly next;
+ ao_poly prev;
+ uint8_t state;
ao_poly actuals;
ao_poly formals;
+ ao_poly formals_tail;
ao_poly frame;
- ao_poly cond;
};
static struct ao_lisp_stack *
ao_lisp_poly_mark(stack->actuals);
ao_lisp_poly_mark(stack->formals);
ao_lisp_poly_mark(stack->frame);
- ao_lisp_poly_mark(stack->cond);
- stack = ao_lisp_poly_stack(stack->next);
+ stack = ao_lisp_poly_stack(stack->prev);
if (ao_lisp_mark_memory(stack, sizeof (struct ao_lisp_stack)))
break;
}
struct ao_lisp_stack *stack = addr;
for (;;) {
- struct ao_lisp_stack *next;
+ struct ao_lisp_stack *prev;
stack->actuals = ao_lisp_poly_move(stack->actuals);
stack->formals = ao_lisp_poly_move(stack->formals);
stack->frame = ao_lisp_poly_move(stack->frame);
- stack->cond = ao_lisp_poly_move(stack->cond);
- next = ao_lisp_ref(stack->next);
- next = ao_lisp_move_memory(next, sizeof (struct ao_lisp_stack));
- stack->next = ao_lisp_stack_poly(next);
- stack = next;
+ prev = ao_lisp_ref(stack->prev);
+ prev = ao_lisp_move_memory(prev, sizeof (struct ao_lisp_stack));
+ stack->prev = ao_lisp_stack_poly(prev);
+ stack = prev;
}
}
};
-static struct ao_lisp_stack *stack;
-static struct ao_lisp_cons *actuals;
-static struct ao_lisp_cons *formals;
-static struct ao_lisp_cons *formals_tail;
-static struct ao_lisp_cons *cond;
-struct ao_lisp_frame *next_frame;
+static struct ao_lisp_stack *ao_lisp_stack;
static uint8_t been_here;
ao_poly
ao_lisp_set_cond(struct ao_lisp_cons *c)
{
- cond = c;
return AO_LISP_NIL;
}
-static int
+static void
+ao_lisp_stack_reset(struct ao_lisp_stack *stack)
+{
+ stack->state = eval_sexpr;
+ stack->actuals = AO_LISP_NIL;
+ stack->formals = AO_LISP_NIL;
+ stack->formals_tail = AO_LISP_NIL;
+ stack->frame = ao_lisp_frame_poly(ao_lisp_frame_current);
+}
+
+static struct ao_lisp_stack *
ao_lisp_stack_push(void)
{
- struct ao_lisp_stack *n = ao_lisp_alloc(sizeof (struct ao_lisp_stack));
- if (!n)
- return 0;
- n->next = ao_lisp_stack_poly(stack);
- n->actuals = ao_lisp_cons_poly(actuals);
- n->formals = ao_lisp_cons_poly(formals);
- n->cond = ao_lisp_cons_poly(cond);
- n->frame = ao_lisp_frame_poly(ao_lisp_frame_current);
- DBG("push frame %d\n", OFFSET(ao_lisp_frame_current));
- stack = n;
- return 1;
+ struct ao_lisp_stack *stack = ao_lisp_alloc(sizeof (struct ao_lisp_stack));
+ if (!stack)
+ return NULL;
+ stack->prev = ao_lisp_stack_poly(ao_lisp_stack);
+ ao_lisp_stack_reset(stack);
+ ao_lisp_stack = stack;
+ DBGI("stack push\n");
+ DBG_IN();
+ return stack;
}
-static void
+static struct ao_lisp_stack *
ao_lisp_stack_pop(void)
{
- actuals = ao_lisp_poly_cons(stack->actuals);
- formals = ao_lisp_poly_cons(stack->formals);
- cond = ao_lisp_poly_cons(stack->cond);
- ao_lisp_frame_current = ao_lisp_poly_frame(stack->frame);
- DBG("pop frame %d\n", OFFSET(ao_lisp_frame_current));
- formals_tail = 0;
-
- /* Recompute the tail of the formals list */
- if (formals) {
- struct ao_lisp_cons *formal;
- for (formal = formals; formal->cdr != AO_LISP_NIL; formal = ao_lisp_poly_cons(formal->cdr));
- formals_tail = formal;
- }
- stack = ao_lisp_poly_stack(stack->next);
+ if (!ao_lisp_stack)
+ return NULL;
+ DBG_OUT();
+ DBGI("stack pop\n");
+ ao_lisp_stack = ao_lisp_poly_stack(ao_lisp_stack->prev);
+ if (ao_lisp_stack)
+ ao_lisp_frame_current = ao_lisp_poly_frame(ao_lisp_stack->frame);
+ else
+ ao_lisp_frame_current = NULL;
+ return ao_lisp_stack;
}
static void
ao_lisp_stack_clear(void)
{
- stack = 0;
- actuals = formals = formals_tail = 0;
- cond = 0;
- ao_lisp_frame_current = 0;
+ ao_lisp_stack = NULL;
+ ao_lisp_frame_current = NULL;
}
struct ao_lisp_cons *args;
int f;
- DBG("func type "); DBG_POLY(func); DBG("\n");
+ DBGI("func type "); DBG_POLY(func); DBG("\n");
if (func == AO_LISP_NIL)
return ao_lisp_error(AO_LISP_INVALID, "func is nil");
- if (ao_lisp_poly_type(func) != AO_LISP_CONS)
- return ao_lisp_error(AO_LISP_INVALID, "func is not list");
- cons = ao_lisp_poly_cons(func);
- if (!ao_lisp_check_argc(_ao_lisp_atom_lambda, cons, 3, 3))
- return AO_LISP_NIL;
- if (!ao_lisp_check_argt(_ao_lisp_atom_lambda, cons, 0, AO_LISP_ATOM, 0))
- return AO_LISP_NIL;
- if (!ao_lisp_check_argt(_ao_lisp_atom_lambda, cons, 1, AO_LISP_CONS, 1))
- return AO_LISP_NIL;
- args = ao_lisp_poly_cons(ao_lisp_arg(cons, 1));
- f = 0;
- while (args) {
- if (ao_lisp_poly_type(args->car) != AO_LISP_ATOM) {
- return ao_lisp_error(ao_lisp_arg(cons, 0), "formal %d is not an atom", f);
+ if (ao_lisp_poly_type(func) == AO_LISP_BUILTIN) {
+ struct ao_lisp_builtin *b = ao_lisp_poly_builtin(func);
+ return b->args;
+ } else if (ao_lisp_poly_type(func) == AO_LISP_CONS) {
+ cons = ao_lisp_poly_cons(func);
+ if (!ao_lisp_check_argc(_ao_lisp_atom_lambda, cons, 3, 3))
+ return AO_LISP_NIL;
+ if (!ao_lisp_check_argt(_ao_lisp_atom_lambda, cons, 0, AO_LISP_ATOM, 0))
+ return AO_LISP_NIL;
+ if (!ao_lisp_check_argt(_ao_lisp_atom_lambda, cons, 1, AO_LISP_CONS, 1))
+ return AO_LISP_NIL;
+ args = ao_lisp_poly_cons(ao_lisp_arg(cons, 1));
+ f = 0;
+ while (args) {
+ if (ao_lisp_poly_type(args->car) != AO_LISP_ATOM) {
+ return ao_lisp_error(ao_lisp_arg(cons, 0), "formal %d is not an atom", f);
+ }
+ args = ao_lisp_poly_cons(args->cdr);
+ f++;
}
- args = ao_lisp_poly_cons(args->cdr);
- f++;
- }
- return ao_lisp_arg(cons, 0);
+ return ao_lisp_arg(cons, 0);
+ } else
+ return ao_lisp_error(AO_LISP_INVALID, "not a func");
}
static int
ao_poly type;
struct ao_lisp_cons *lambda;
struct ao_lisp_cons *args;
+ struct ao_lisp_frame *next_frame;
int args_wanted;
int args_provided;
lambda = ao_lisp_poly_cons(ao_lisp_arg(cons, 0));
- DBG("lambda "); DBG_CONS(lambda); DBG("\n");
+ DBGI("lambda "); DBG_CONS(lambda); DBG("\n");
type = ao_lisp_arg(lambda, 0);
args = ao_lisp_poly_cons(ao_lisp_arg(lambda, 1));
if (args_wanted != args_provided)
return ao_lisp_error(AO_LISP_INVALID, "need %d args, not %d", args_wanted, args_provided);
next_frame = ao_lisp_frame_new(args_wanted, 0);
- DBG("new frame %d\n", OFFSET(next_frame));
+ DBGI("new frame %d\n", OFFSET(next_frame));
switch (type) {
case _ao_lisp_atom_lambda: {
int f;
next_frame->vals[0].val = ao_lisp_cons_poly(cons);
break;
}
+ next_frame->next = ao_lisp_frame_poly(ao_lisp_frame_current);
+ ao_lisp_frame_current = next_frame;
+ ao_lisp_stack->frame = ao_lisp_frame_poly(next_frame);
return ao_lisp_arg(lambda, 2);
}
ao_poly
ao_lisp_eval(ao_poly v)
{
- struct ao_lisp_cons *formal;
- int cons = 0;
+ struct ao_lisp_stack *stack;
+ ao_poly formal;
if (!been_here) {
been_here = 1;
ao_lisp_root_add(&ao_lisp_stack_type, &stack);
- ao_lisp_root_add(&ao_lisp_cons_type, &actuals);
- ao_lisp_root_add(&ao_lisp_cons_type, &formals);
- ao_lisp_root_add(&ao_lisp_cons_type, &formals_tail);
}
- stack = 0;
- actuals = 0;
- formals = 0;
- formals_tail = 0;
- cond = 0;
+
+ stack = ao_lisp_stack_push();
+
for (;;) {
+ if (ao_lisp_exception)
+ return AO_LISP_NIL;
+ switch (stack->state) {
+ case eval_sexpr:
+ DBGI("sexpr: "); DBG_POLY(v); DBG("\n");
+ switch (ao_lisp_poly_type(v)) {
+ case AO_LISP_CONS:
+ if (v == AO_LISP_NIL) {
+ stack->state = eval_exec;
+ break;
+ }
+ stack->actuals = v;
+ stack = ao_lisp_stack_push();
+ v = ao_lisp_poly_cons(v)->car;
+ break;
+ case AO_LISP_ATOM:
+ v = ao_lisp_atom_get(v);
+ /* fall through */
+ case AO_LISP_INT:
+ case AO_LISP_STRING:
+ stack->state = eval_val;
+ break;
+ }
+ break;
+ case eval_val:
+ DBGI("val: "); DBG_POLY(v); DBG("\n");
+ stack = ao_lisp_stack_pop();
+ if (!stack)
+ return v;
+
+ stack->state = eval_sexpr;
+ /* Check what kind of function we've got */
+ if (!stack->formals) {
+ switch (func_type(v)) {
+ case AO_LISP_LAMBDA:
+ case _ao_lisp_atom_lambda:
+ case AO_LISP_LEXPR:
+ case _ao_lisp_atom_lexpr:
+ DBGI(".. lambda or lexpr\n");
+ break;
+ case AO_LISP_NLAMBDA:
+ case _ao_lisp_atom_nlambda:
+ case AO_LISP_MACRO:
+ case _ao_lisp_atom_macro:
+ DBGI(".. nlambda or macro\n");
+ stack->formals = stack->actuals;
+ stack->state = eval_exec_direct;
+ break;
+ }
+ if (stack->state == eval_exec_direct)
+ break;
+ }
+
+ formal = ao_lisp_cons_poly(ao_lisp_cons_cons(v, NULL));
+ if (!formal) {
+ ao_lisp_stack_clear();
+ return AO_LISP_NIL;
+ }
+
+ if (stack->formals_tail)
+ ao_lisp_poly_cons(stack->formals_tail)->cdr = formal;
+ else
+ stack->formals = formal;
+ stack->formals_tail = formal;
+
+ DBGI("formals now "); DBG_POLY(stack->formals); DBG("\n");
+
+ v = ao_lisp_poly_cons(stack->actuals)->cdr;
+
+ break;
+ case eval_exec:
+ v = ao_lisp_poly_cons(stack->formals)->car;
+ case eval_exec_direct:
+ DBGI("exec: "); DBG_POLY(v); DBG(" formals "); DBG_POLY(stack->formals); DBG ("\n");
+ if (ao_lisp_poly_type(v) == AO_LISP_BUILTIN) {
+ struct ao_lisp_builtin *b = ao_lisp_poly_builtin(v);
+
+ v = ao_lisp_func(b) (ao_lisp_poly_cons(ao_lisp_poly_cons(stack->formals)->cdr));
+ DBGI("builtin result:"); DBG_POLY(v); DBG ("\n");
+ if (ao_lisp_exception) {
+ ao_lisp_stack_clear();
+ return AO_LISP_NIL;
+ }
+ stack->state = eval_val;
+ break;
+ } else {
+ v = ao_lisp_lambda(ao_lisp_poly_cons(stack->formals));
+ ao_lisp_stack_reset(stack);
+ }
+ break;
+ }
+ }
+}
+#if 0
+
restart:
if (cond) {
+ DBGI("cond is now "); DBG_CONS(cond); DBG("\n");
if (cond->car == AO_LISP_NIL) {
cond = AO_LISP_NIL;
v = AO_LISP_NIL;
actuals = ao_lisp_poly_cons(v);
formals = NULL;
formals_tail = NULL;
+ save_cond = cond;
cond = NULL;
v = actuals->car;
// DBG("start: formals"); DBG_CONS(formals); DBG("\n");
}
+ if (ao_lisp_poly_type(v) == AO_LISP_BUILTIN) {
+ struct ao_lisp_builtin *b = ao_lisp_poly_builtin(v);
+ switch (b->args) {
+ case AO_LISP_NLAMBDA:
+ formals = actuals;
+ goto eval;
+
+ case AO_LISP_MACRO:
+ v = ao_lisp_func(b)(ao_lisp_poly_cons(actuals->cdr));
+ DBG("macro "); DBG_POLY(ao_lisp_cons_poly(actuals));
+ DBG(" -> "); DBG_POLY(v);
+ DBG("\n");
+ if (ao_lisp_poly_type(v) != AO_LISP_CONS) {
+ ao_lisp_error(AO_LISP_INVALID, "macro didn't return list");
+ goto bail;
+ }
+ /* Reset frame to the new list */
+ actuals = ao_lisp_poly_cons(v);
+ v = actuals->car;
+ goto restart;
+ }
/* Evaluate primitive types */
DBG ("actual: "); DBG_POLY(v); DBG("\n");
/* Evaluate the resulting list */
if (ao_lisp_poly_type(v) == AO_LISP_BUILTIN) {
+ struct ao_lisp_cons *old_cond = cond;
struct ao_lisp_builtin *b = ao_lisp_poly_builtin(v);
v = ao_lisp_func(b) (ao_lisp_poly_cons(formals->cdr));
if (ao_lisp_exception)
goto bail;
- if (cond)
+ if (cond != old_cond) {
+ DBG("cond changed from "); DBG_CONS(old_cond); DBG(" to "); DBG_CONS(cond); DBG("\n");
+ actuals = NULL;
+ formals = 0;
+ formals_tail = 0;
+ save_cons = cons;
+ cons = 0;
goto restart;
+ }
} else {
v = ao_lisp_lambda(formals);
if (ao_lisp_exception)
goto bail;
}
+ cond_done:
--cons;
if (cons) {
ao_lisp_stack_pop();
next_frame = 0;
goto restart;
}
- if (cond) {
- if (v) {
- v = ao_lisp_poly_cons(cond->car)->cdr;
- if (v != AO_LISP_NIL) {
- v = ao_lisp_poly_cons(v)->car;
- goto restart;
- }
- } else {
- cond = ao_lisp_poly_cons(cond->cdr);
- goto restart;
+ }
+ if (cond) {
+ DBG("next cond cons is %d\n", cons);
+ if (v) {
+ v = ao_lisp_poly_cons(cond->car)->cdr;
+ cond = 0;
+ cons = save_cons;
+ if (v != AO_LISP_NIL) {
+ v = ao_lisp_poly_cons(v)->car;
+ DBG("cond complete, sexpr is "); DBG_POLY(v); DBG("\n");
}
+ goto cond_done;
+ } else {
+ cond = ao_lisp_poly_cons(cond->cdr);
+ DBG("next cond is "); DBG_CONS(cond); DBG("\n");
+ goto restart;
}
}
if (!cons)
bail:
ao_lisp_stack_clear();
return AO_LISP_NIL;
-}
+#endif
+
projects / fw / altos / commitdiff