X-Git-Url: https://git.gag.com/?p=fw%2Faltos;a=blobdiff_plain;f=src%2Flisp%2Fao_lisp_eval.c;h=3af567964deab8a4f87d13a26d13425e3508e901;hp=f41962195ee7bd4227d1ce91e5cbc87138d807ae;hb=974717eb9dad105c9897ee24f953d98d57eaec77;hpb=794718abc62f4610495fe2bd535a2b67bc46573c

diff --git a/src/lisp/ao_lisp_eval.c b/src/lisp/ao_lisp_eval.c
index f4196219..3af56796 100644
--- a/src/lisp/ao_lisp_eval.c
+++ b/src/lisp/ao_lisp_eval.c
@@ -12,10 +12,12 @@
  * General Public License for more details.
  */
 
-#define DBG_EVAL 1
+#define DBG_EVAL 0
 #include "ao_lisp.h"
 #include <assert.h>
 
+const struct ao_lisp_type ao_lisp_stack_type;
+
 static int
 stack_size(void *addr)
 {
@@ -32,47 +34,50 @@ stack_mark(void *addr)
 		ao_lisp_poly_mark(stack->values, 0);
 		/* no need to mark values_tail */
 		ao_lisp_poly_mark(stack->frame, 0);
-		ao_lisp_poly_mark(stack->macro_frame, 0);
+		ao_lisp_poly_mark(stack->list, 0);
 		stack = ao_lisp_poly_stack(stack->prev);
-		if (ao_lisp_mark_memory(stack, sizeof (struct ao_lisp_stack)))
+		if (ao_lisp_mark_memory(&ao_lisp_stack_type, stack))
 			break;
 	}
 }
 
-static const struct ao_lisp_type ao_lisp_stack_type;
-
 static void
 stack_move(void *addr)
 {
 	struct ao_lisp_stack	*stack = addr;
 
 	while (stack) {
-		void	*prev;
-		int	ret;
+		struct ao_lisp_stack	*prev;
+		int			ret;
 		(void) ao_lisp_poly_move(&stack->sexprs, 0);
 		(void) ao_lisp_poly_move(&stack->values, 0);
 		(void) ao_lisp_poly_move(&stack->values_tail, 0);
 		(void) ao_lisp_poly_move(&stack->frame, 0);
-		(void) ao_lisp_poly_move(&stack->macro_frame, 0);
+		(void) ao_lisp_poly_move(&stack->list, 0);
 		prev = ao_lisp_poly_stack(stack->prev);
-		ret = ao_lisp_move(&ao_lisp_stack_type, &prev);
+		if (!prev)
+			break;
+		ret = ao_lisp_move_memory(&ao_lisp_stack_type, (void **) &prev);
 		if (prev != ao_lisp_poly_stack(stack->prev))
 			stack->prev = ao_lisp_stack_poly(prev);
 		if (ret)
 			break;
-		stack = ao_lisp_poly_stack(stack->prev);
+		stack = prev;
 	}
 }
 
-static const struct ao_lisp_type ao_lisp_stack_type = {
+const struct ao_lisp_type ao_lisp_stack_type = {
 	.size = stack_size,
 	.mark = stack_mark,
-	.move = stack_move
+	.move = stack_move,
+	.name = "stack"
 };
 
 struct ao_lisp_stack		*ao_lisp_stack;
 ao_poly				ao_lisp_v;
 
+struct ao_lisp_stack		*ao_lisp_stack_free_list;
+
 ao_poly
 ao_lisp_set_cond(struct ao_lisp_cons *c)
 {
@@ -85,50 +90,54 @@ static void
 ao_lisp_stack_reset(struct ao_lisp_stack *stack)
 {
 	stack->state = eval_sexpr;
-	stack->macro = 0;
 	stack->sexprs = AO_LISP_NIL;
 	stack->values = AO_LISP_NIL;
 	stack->values_tail = AO_LISP_NIL;
 }
 
-static void
-ao_lisp_frames_dump(void)
-{
-	struct ao_lisp_stack *s;
-	DBGI(".. current frame: "); DBG_POLY(ao_lisp_frame_poly(ao_lisp_frame_current)); DBG("\n");
-	for (s = ao_lisp_stack; s; s = ao_lisp_poly_stack(s->prev)) {
-		DBGI(".. stack frame: "); DBG_POLY(s->frame); DBG("\n");
-		DBGI(".. macro frame: "); DBG_POLY(s->frame); DBG("\n");
-	}
-}
 
 static int
 ao_lisp_stack_push(void)
 {
-	DBGI("stack push\n");
-	DBG_IN();
-	struct ao_lisp_stack	*stack = ao_lisp_alloc(sizeof (struct ao_lisp_stack));
-	if (!stack)
-		return 0;
+	struct ao_lisp_stack	*stack;
+	if (ao_lisp_stack_free_list) {
+		stack = ao_lisp_stack_free_list;
+		ao_lisp_stack_free_list = ao_lisp_poly_stack(stack->prev);
+	} else {
+		stack = ao_lisp_alloc(sizeof (struct ao_lisp_stack));
+		if (!stack)
+			return 0;
+	}
 	stack->prev = ao_lisp_stack_poly(ao_lisp_stack);
 	stack->frame = ao_lisp_frame_poly(ao_lisp_frame_current);
 	stack->list = AO_LISP_NIL;
 	ao_lisp_stack = stack;
 	ao_lisp_stack_reset(stack);
-	ao_lisp_frames_dump();
+	DBGI("stack push\n");
+	DBG_FRAMES();
+	DBG_IN();
 	return 1;
 }
 
 static void
 ao_lisp_stack_pop(void)
 {
+	ao_poly	prev;
+
 	if (!ao_lisp_stack)
 		return;
-	ao_lisp_frame_current = ao_lisp_poly_frame(ao_lisp_stack->frame);
-	ao_lisp_stack = ao_lisp_poly_stack(ao_lisp_stack->prev);
+	prev = ao_lisp_stack->prev;
+	ao_lisp_stack->prev = ao_lisp_stack_poly(ao_lisp_stack_free_list);
+	ao_lisp_stack_free_list = ao_lisp_stack;
+
+	ao_lisp_stack = ao_lisp_poly_stack(prev);
+	if (ao_lisp_stack)
+		ao_lisp_frame_current = ao_lisp_poly_frame(ao_lisp_stack->frame);
+	else
+		ao_lisp_frame_current = NULL;
 	DBG_OUT();
 	DBGI("stack pop\n");
-	ao_lisp_frames_dump();
+	DBG_FRAMES();
 }
 
 static void
@@ -146,7 +155,7 @@ func_type(ao_poly func)
 		return ao_lisp_error(AO_LISP_INVALID, "func is nil");
 	switch (ao_lisp_poly_type(func)) {
 	case AO_LISP_BUILTIN:
-		return ao_lisp_poly_builtin(func)->args;
+		return ao_lisp_poly_builtin(func)->args & AO_LISP_FUNC_MASK;
 	case AO_LISP_LAMBDA:
 		return ao_lisp_poly_lambda(func)->args;
 	default:
@@ -246,33 +255,11 @@ static int
 ao_lisp_eval_val(void)
 {
 	DBGI("val: "); DBG_POLY(ao_lisp_v); DBG("\n");
-	if (ao_lisp_stack->macro) {
-		DBGI("..macro %d\n", ao_lisp_stack->macro);
-		DBGI("..current frame "); DBG_POLY(ao_lisp_frame_poly(ao_lisp_frame_current)); DBG("\n");
-		DBGI("..saved frame   "); DBG_POLY(ao_lisp_stack->frame); DBG("\n");
-		DBGI("..macro frame   "); DBG_POLY(ao_lisp_stack->macro_frame); DBG("\n");
-		DBGI("..sexprs       "); DBG_POLY(ao_lisp_stack->sexprs); DBG("\n");
-		DBGI("..values       "); DBG_POLY(ao_lisp_stack->values); DBG("\n");
-		/*
-		 * Re-use the current stack to evaluate
-		 * the value from the macro
-		 */
-		ao_lisp_stack->state = eval_sexpr;
-//		assert(ao_lisp_stack->frame == ao_lisp_stack->macro_frame);
-		ao_lisp_frame_current = ao_lisp_poly_frame(ao_lisp_stack->macro_frame);
-		ao_lisp_stack->frame = ao_lisp_stack->macro_frame;
-		ao_lisp_stack->macro = 0;
-		ao_lisp_stack->macro_frame = AO_LISP_NIL;
-		ao_lisp_stack->sexprs = AO_LISP_NIL;
-		ao_lisp_stack->values = AO_LISP_NIL;
-		ao_lisp_stack->values_tail = AO_LISP_NIL;
-	} else {
-		/*
-		 * Value computed, pop the stack
-		 * to figure out what to do with the value
-		 */
-		ao_lisp_stack_pop();
-	}
+	/*
+	 * Value computed, pop the stack
+	 * to figure out what to do with the value
+	 */
+	ao_lisp_stack_pop();
 	DBGI("..state %d\n", ao_lisp_stack ? ao_lisp_stack->state : -1);
 	return 1;
 }
@@ -280,22 +267,25 @@ ao_lisp_eval_val(void)
 /*
  * A formal has been computed.
  *
- * If this is the first formal, then
- * check to see if we've got a lamda/lexpr or
- * macro/nlambda.
+ * If this is the first formal, then check to see if we've got a
+ * lamda/lexpr or macro/nlambda.
+ *
+ * For lambda/lexpr, go compute another formal.  This will terminate
+ * when the sexpr state sees nil.
  *
- * For lambda/lexpr, go compute another formal.
- * This will terminate when the sexpr state
- * sees nil.
+ * For macro/nlambda, we're done, so move the sexprs into the values
+ * and go execute it.
  *
- * For macro/nlambda, we're done, so move the
- * sexprs into the values and go execute it.
+ * Macros have an additional step of saving a stack frame holding the
+ * macro value execution context, which then gets the result of the
+ * macro to run
  */
 
 static int
 ao_lisp_eval_formal(void)
 {
-	ao_poly formal;
+	ao_poly			formal;
+	struct ao_lisp_stack	*prev;
 
 	DBGI("formal: "); DBG_POLY(ao_lisp_v); DBG("\n");
 
@@ -307,17 +297,33 @@ ao_lisp_eval_formal(void)
 			DBGI(".. lambda or lexpr\n");
 			break;
 		case AO_LISP_FUNC_MACRO:
-			ao_lisp_stack->macro = 1;
-			DBGI(".. macro %d\n", ao_lisp_stack->macro);
-			DBGI(".. frame "); DBG_POLY(ao_lisp_frame_poly(ao_lisp_frame_current)); DBG("\n");
-			DBGI(".. saved frame "); DBG_POLY(ao_lisp_stack->frame); DBG("\n");
-			ao_lisp_stack->macro_frame = ao_lisp_stack->frame;
+			/* Evaluate the result once more */
+			ao_lisp_stack->state = eval_macro;
+			if (!ao_lisp_stack_push())
+				return 0;
+
+			/* After the function returns, take that
+			 * value and re-evaluate it
+			 */
+			prev = ao_lisp_poly_stack(ao_lisp_stack->prev);
+			ao_lisp_stack->state = eval_sexpr;
+			ao_lisp_stack->sexprs = prev->sexprs;
+
+			DBGI(".. start macro\n");
+			DBGI(".. sexprs       "); DBG_POLY(ao_lisp_stack->sexprs); DBG("\n");
+			DBGI(".. values       "); DBG_POLY(ao_lisp_stack->values); DBG("\n");
+			DBG_FRAMES();
+
 			/* fall through ... */
 		case AO_LISP_FUNC_NLAMBDA:
 			DBGI(".. nlambda or macro\n");
+
+			/* use the raw sexprs as values */
 			ao_lisp_stack->values = ao_lisp_stack->sexprs;
 			ao_lisp_stack->values_tail = AO_LISP_NIL;
 			ao_lisp_stack->state = eval_exec;
+
+			/* ready to execute now */
 			return 1;
 		case -1:
 			return 0;
@@ -366,12 +372,15 @@ static int
 ao_lisp_eval_exec(void)
 {
 	ao_poly v;
+	struct ao_lisp_builtin	*builtin;
+
 	DBGI("exec: "); DBG_POLY(ao_lisp_v); DBG(" values "); DBG_POLY(ao_lisp_stack->values); DBG ("\n");
 	ao_lisp_stack->sexprs = AO_LISP_NIL;
 	switch (ao_lisp_poly_type(ao_lisp_v)) {
 	case AO_LISP_BUILTIN:
 		ao_lisp_stack->state = eval_val;
-		v = ao_lisp_func(ao_lisp_poly_builtin(ao_lisp_v)) (
+		builtin = ao_lisp_poly_builtin(ao_lisp_v);
+		v = ao_lisp_func(builtin) (
 			ao_lisp_poly_cons(ao_lisp_poly_cons(ao_lisp_stack->values)->cdr));
 		DBG_DO(if (!ao_lisp_exception && ao_lisp_poly_builtin(ao_lisp_v)->func == builtin_set) {
 				struct ao_lisp_cons *cons = ao_lisp_poly_cons(ao_lisp_stack->values);
@@ -379,6 +388,10 @@ ao_lisp_eval_exec(void)
 				ao_poly val = ao_lisp_arg(cons, 2);
 				DBGI("set "); DBG_POLY(atom); DBG(" = "); DBG_POLY(val); DBG("\n");
 			});
+		builtin = ao_lisp_poly_builtin(ao_lisp_v);
+		if (builtin->args & AO_LISP_FUNC_FREE_ARGS)
+			ao_lisp_cons_free(ao_lisp_poly_cons(ao_lisp_stack->values));
+
 		ao_lisp_v = v;
 		DBGI(".. result "); DBG_POLY(ao_lisp_v); DBG ("\n");
 		DBGI(".. frame "); DBG_POLY(ao_lisp_frame_poly(ao_lisp_frame_current)); DBG("\n");
@@ -386,8 +399,7 @@ ao_lisp_eval_exec(void)
 	case AO_LISP_LAMBDA:
 		ao_lisp_stack->state = eval_sexpr;
 		DBGI(".. frame "); DBG_POLY(ao_lisp_frame_poly(ao_lisp_frame_current)); DBG("\n");
-		ao_lisp_v = ao_lisp_lambda_eval(ao_lisp_poly_lambda(ao_lisp_v),
-						ao_lisp_poly_cons(ao_lisp_stack->values));
+		ao_lisp_v = ao_lisp_lambda_eval();
 		DBGI(".. sexpr "); DBG_POLY(ao_lisp_v); DBG("\n");
 		DBGI(".. frame "); DBG_POLY(ao_lisp_frame_poly(ao_lisp_frame_current)); DBG("\n");
 		break;
@@ -397,14 +409,6 @@ ao_lisp_eval_exec(void)
 	return 1;
 }
 
-static int
-ao_lisp_eval_lambda_done(void)
-{
-	DBGI("lambda_done: "); DBG_POLY(ao_lisp_v); DBG("\n");
-	DBG_STACK();
-	return 1;
-}
-
 /*
  * Start evaluating the next cond clause
  *
@@ -458,12 +462,11 @@ ao_lisp_eval_cond_test(void)
 		struct ao_lisp_cons *car = ao_lisp_poly_cons(ao_lisp_poly_cons(ao_lisp_stack->sexprs)->car);
 		struct ao_lisp_cons *c = ao_lisp_poly_cons(car->cdr);
 
-		ao_lisp_stack->state = eval_val;
 		if (c) {
+			ao_lisp_stack->state = eval_sexpr;
 			ao_lisp_v = c->car;
-			if (!ao_lisp_stack_push())
-				return 0;
-		}
+		} else
+			ao_lisp_stack->state = eval_val;
 	} else {
 		ao_lisp_stack->sexprs = ao_lisp_poly_cons(ao_lisp_stack->sexprs)->cdr;
 		DBGI("next cond: "); DBG_POLY(ao_lisp_stack->sexprs); DBG("\n");
@@ -472,6 +475,104 @@ ao_lisp_eval_cond_test(void)
 	return 1;
 }
 
+/*
+ * Evaluate a list of sexprs, returning the value from the last one.
+ *
+ * ao_lisp_progn records the list in stack->sexprs, so we just need to
+ * walk that list. Set ao_lisp_v to the car of the list and jump to
+ * eval_sexpr. When that's done, it will land in eval_val. For all but
+ * the last, leave a stack frame with eval_progn set so that we come
+ * back here. For the last, don't add a stack frame so that we can
+ * just continue on.
+ */
+static int
+ao_lisp_eval_progn(void)
+{
+	DBGI("progn: "); DBG_POLY(ao_lisp_v); DBG(" sexprs "); DBG_POLY(ao_lisp_stack->sexprs); DBG("\n");
+	DBGI(".. frame "); DBG_POLY(ao_lisp_frame_poly(ao_lisp_frame_current)); DBG("\n");
+	DBGI(".. saved frame "); DBG_POLY(ao_lisp_stack->frame); DBG("\n");
+
+	if (!ao_lisp_stack->sexprs) {
+		ao_lisp_v = AO_LISP_NIL;
+		ao_lisp_stack->state = eval_val;
+	} else {
+		ao_lisp_v = ao_lisp_poly_cons(ao_lisp_stack->sexprs)->car;
+		ao_lisp_stack->sexprs = ao_lisp_poly_cons(ao_lisp_stack->sexprs)->cdr;
+		if (ao_lisp_stack->sexprs) {
+			ao_lisp_stack->state = eval_progn;
+			if (!ao_lisp_stack_push())
+				return 0;
+		}
+		ao_lisp_stack->state = eval_sexpr;
+	}
+	return 1;
+}
+
+/*
+ * Conditionally execute a list of sexprs while the first is true
+ */
+static int
+ao_lisp_eval_while(void)
+{
+	DBGI("while: "); DBG_POLY(ao_lisp_stack->sexprs); DBG("\n");
+	DBGI(".. frame "); DBG_POLY(ao_lisp_frame_poly(ao_lisp_frame_current)); DBG("\n");
+	DBGI(".. saved frame "); DBG_POLY(ao_lisp_stack->frame); DBG("\n");
+
+	if (!ao_lisp_stack->sexprs) {
+		ao_lisp_v = AO_LISP_NIL;
+		ao_lisp_stack->state = eval_val;
+	} else {
+		ao_lisp_v = ao_lisp_poly_cons(ao_lisp_stack->sexprs)->car;
+		ao_lisp_stack->state = eval_while_test;
+		if (!ao_lisp_stack_push())
+			return 0;
+		ao_lisp_stack->state = eval_sexpr;
+	}
+	return 1;
+}
+
+/*
+ * Check the while condition, terminate the loop if nil. Otherwise keep going
+ */
+static int
+ao_lisp_eval_while_test(void)
+{
+	DBGI("while_test: "); DBG_POLY(ao_lisp_v); DBG(" sexprs "); DBG_POLY(ao_lisp_stack->sexprs); DBG("\n");
+	DBGI(".. frame "); DBG_POLY(ao_lisp_frame_poly(ao_lisp_frame_current)); DBG("\n");
+	DBGI(".. saved frame "); DBG_POLY(ao_lisp_stack->frame); DBG("\n");
+
+	if (ao_lisp_v) {
+		ao_lisp_v = ao_lisp_poly_cons(ao_lisp_stack->sexprs)->cdr;
+		if (ao_lisp_v)
+			ao_lisp_v = ao_lisp_poly_cons(ao_lisp_v)->car;
+		ao_lisp_stack->state = eval_while;
+		if (!ao_lisp_stack_push())
+			return 0;
+	}
+	else
+		ao_lisp_stack->state = eval_val;
+	return 1;
+}
+
+/*
+ * Replace the original sexpr with the macro expansion, then
+ * execute that
+ */
+static int
+ao_lisp_eval_macro(void)
+{
+	DBGI("macro: "); DBG_POLY(ao_lisp_v); DBG(" sexprs "); DBG_POLY(ao_lisp_stack->sexprs); DBG("\n");
+
+	if (ao_lisp_poly_type(ao_lisp_v) == AO_LISP_CONS) {
+		*ao_lisp_poly_cons(ao_lisp_stack->sexprs) = *ao_lisp_poly_cons(ao_lisp_v);
+		ao_lisp_v = ao_lisp_stack->sexprs;
+		DBGI("sexprs rewritten to: "); DBG_POLY(ao_lisp_v); DBG("\n");
+	}
+	ao_lisp_stack->sexprs = AO_LISP_NIL;
+	ao_lisp_stack->state = eval_sexpr;
+	return 1;
+}
+
 static int (*const evals[])(void) = {
 	[eval_sexpr] = ao_lisp_eval_sexpr,
 	[eval_val] = ao_lisp_eval_val,
@@ -479,25 +580,39 @@ static int (*const evals[])(void) = {
 	[eval_exec] = ao_lisp_eval_exec,
 	[eval_cond] = ao_lisp_eval_cond,
 	[eval_cond_test] = ao_lisp_eval_cond_test,
+	[eval_progn] = ao_lisp_eval_progn,
+	[eval_while] = ao_lisp_eval_while,
+	[eval_while_test] = ao_lisp_eval_while_test,
+	[eval_macro] = ao_lisp_eval_macro,
 };
 
+/*
+ * Called at restore time to reset all execution state
+ */
+
+void
+ao_lisp_eval_clear_globals(void)
+{
+	ao_lisp_stack = NULL;
+	ao_lisp_frame_current = NULL;
+	ao_lisp_v = AO_LISP_NIL;
+}
+
+int
+ao_lisp_eval_restart(void)
+{
+	return ao_lisp_stack_push();
+}
+
 ao_poly
 ao_lisp_eval(ao_poly _v)
 {
-	static uint8_t been_here;
-
 	ao_lisp_v = _v;
-	if (!been_here) {
-		been_here = 1;
-		ao_lisp_root_add(&ao_lisp_stack_type, &ao_lisp_stack);
-		ao_lisp_root_poly_add(&ao_lisp_v);
-	}
 
 	if (!ao_lisp_stack_push())
 		return AO_LISP_NIL;
 
 	while (ao_lisp_stack) {
-//		DBG_STACK();
 		if (!(*evals[ao_lisp_stack->state])() || ao_lisp_exception) {
 			ao_lisp_stack_clear();
 			return AO_LISP_NIL;