fixes, and array dot-number assign

include/lang2/bytecode.h

@@ -30,6 +30,14 @@ enum l2_opcode {
 	 */
 	L2_OP_POP,
 
+	/*
+	 * Swap the top and second-top elements, then pop the new top element.
+	 * Pop <word1>
+	 * Pop <word2>
+	 * Push <word1>
+	 */
+	L2_OP_SWAP_POP,
+
 	/*
 	 * Duplicate the top element on the stack.
 	 * Push <word at <sptr> - 1>
@@ -173,11 +181,20 @@ enum l2_opcode {
 	/*
 	 * Look up a value from an array.
 	 * Pop <key>
-	 * Pop <arr>
-	 * Push <arr[<key>]>
+	 * Read <val>
+	 * Read <arr>
+	 * Assign <val> to <arr[<key>]>
 	 */
 	L2_OP_DIRECT_ARRAY_LOOKUP,
 
+	/*
+	 * Set a value in an array.
+	 * Pop <key>
+	 * Read <arr>
+	 * Push <arr[<key>]>
+	 */
+	L2_OP_DIRECT_ARRAY_SET,
+
 	/*
 	 * Halt execution.
 	 */

include/lang2/gen/gen.h

@@ -25,6 +25,7 @@ void l2_gen_free(struct l2_generator *gen);
 void l2_gen_halt(struct l2_generator *gen);
 void l2_gen_rjmp(struct l2_generator *gen, l2_word len);
 void l2_gen_pop(struct l2_generator *gen);
+void l2_gen_swap_pop(struct l2_generator *gen);
 void l2_gen_push(struct l2_generator *gen, l2_word word);
 void l2_gen_ret(struct l2_generator *gen);
 void l2_gen_number(struct l2_generator *gen, double num);
@@ -36,6 +37,7 @@ void l2_gen_namespace(struct l2_generator *gen);
 void l2_gen_namespace_set(struct l2_generator *gen, char **ident);
 void l2_gen_namespace_lookup(struct l2_generator *gen, char **ident);
 void l2_gen_direct_array_lookup(struct l2_generator *gen, int number);
+void l2_gen_direct_array_set(struct l2_generator *gen, int number);
 void l2_gen_stack_frame_lookup(struct l2_generator *gen, char **ident);
 void l2_gen_stack_frame_set(struct l2_generator *gen, char **ident);
 void l2_gen_stack_frame_replace(struct l2_generator *gen, char **ident);

lib/gen/gen.c

@@ -45,6 +45,10 @@ void l2_gen_pop(struct l2_generator *gen) {
 	put(gen, L2_OP_POP);
 }
 
+void l2_gen_swap_pop(struct l2_generator *gen) {
+	put(gen, L2_OP_SWAP_POP);
+}
+
 void l2_gen_push(struct l2_generator *gen, l2_word word) {
 	put(gen, L2_OP_PUSH);
 	put(gen, word);
@@ -145,6 +149,12 @@ void l2_gen_direct_array_lookup(struct l2_generator *gen, int number) {
 	put(gen, L2_OP_DIRECT_ARRAY_LOOKUP);
 }
 
+void l2_gen_direct_array_set(struct l2_generator *gen, int number) {
+	put(gen, L2_OP_PUSH);
+	put(gen, number);
+	put(gen, L2_OP_DIRECT_ARRAY_SET);
+}
+
 void l2_gen_stack_frame_lookup(struct l2_generator *gen, char **ident) {
 	size_t atom_id = l2_strset_put(&gen->atomset, ident);
 	put(gen, L2_OP_PUSH);

lib/parse/parse.c

@@ -294,13 +294,14 @@ static int parse_arg_level_expression(
 			char *ident = l2_token_extract_str(tok2);
 			l2_lexer_consume(lexer); // '.'
 			l2_lexer_consume(lexer); // ident
-			l2_lexer_consume(lexer); // equals
+			l2_lexer_consume(lexer); // '='
 
 			if (parse_expression(lexer, gen, err) < 0) {
 				return -1;
 			}
 
 			l2_gen_namespace_set(gen, &ident);
+			l2_gen_swap_pop(gen);
 		} else if (tok->kind == L2_TOK_PERIOD && tok2->kind == L2_TOK_IDENT) {
 			l2_trace_scope("namespace lookup");
 			l2_trace("ident '%s'", tok2->v.str);
@@ -309,6 +310,18 @@ static int parse_arg_level_expression(
 			l2_lexer_consume(lexer); // ident
 
 			l2_gen_namespace_lookup(gen, &ident);
+		} else if (tok->kind == L2_TOK_DOT_NUMBER && tok2->kind == L2_TOK_EQUALS) {
+			l2_trace_scope("direct array assign");
+			int number = tok->v.integer;
+			l2_lexer_consume(lexer); // dot-number
+			l2_lexer_consume(lexer); // '='
+
+			if (parse_expression(lexer, gen, err) < 0) {
+				return -1;
+			}
+
+			l2_gen_direct_array_set(gen, number);
+			l2_gen_swap_pop(gen);
 		} else if (tok->kind == L2_TOK_DOT_NUMBER) {
 			l2_trace_scope("direct array lookup");
 			int number = tok->v.integer;

lib/vm/print.c

@@ -117,13 +117,13 @@ void l2_vm_print_op(l2_word *ops, size_t opcount, size_t *ptr) {
 	switch (opcode) {
 	case L2_OP_NOP:
 		printf("NOP\n");
-		break;
+		return;
 
 	case L2_OP_PUSH:
 		printf("PUSH ");
 		print_op_num(ops, opcount, (*ptr)++);
 		printf("\n");
-		break;
+		return;
 
 	case L2_OP_PUSH_2:
 		printf("PUSH2 ");
@@ -131,96 +131,105 @@ void l2_vm_print_op(l2_word *ops, size_t opcount, size_t *ptr) {
 		printf(" ");
 		print_op_num(ops, opcount, (*ptr)++);
 		printf("\n");
-		break;
+		return;
 
 	case L2_OP_POP:
 		printf("POP\n");
-		break;
+		return;
+
+	case L2_OP_SWAP_POP:
+		printf("SWAP_POP\n");
+		return;
 
 	case L2_OP_DUP:
 		printf("DUP\n");
-		break;
+		return;
 
 	case L2_OP_ADD:
 		printf("ADD\n");
-		break;
+		return;
 
 	case L2_OP_FUNC_CALL:
 		printf("FUNC_CALL\n");
-		break;
+		return;
 
 	case L2_OP_RJMP:
 		printf("RJMP\n");
-		break;
+		return;
 
 	case L2_OP_STACK_FRAME_LOOKUP:
 		printf("STACK_FRAME_LOOKUP\n");
-		break;
+		return;
 
 	case L2_OP_STACK_FRAME_SET:
 		printf("STACK_FRAME_SET\n");
-		break;
+		return;
+
+	case L2_OP_STACK_FRAME_REPLACE:
+		printf("STACK_FRAME_REPLACE\n");
+		return;
 
 	case L2_OP_RET:
 		printf("RET\n");
-		break;
+		return;
 
 	case L2_OP_ALLOC_ATOM:
 		printf("ALLOC_ATOM\n");
-		break;
+		return;
 
 	case L2_OP_ALLOC_REAL:
 		printf("ALLOC_REAL\n");
-		break;
+		return;
 
 	case L2_OP_ALLOC_BUFFER_STATIC:
 		printf("ALLOC_BUFFER_STATIC\n");
-		break;
+		return;
 
 	case L2_OP_ALLOC_BUFFER_ZERO:
 		printf("ALLOC_BUFFER_ZERO\n");
-		break;
+		return;
 
 	case L2_OP_ALLOC_ARRAY:
 		printf("ALLOC_ARRAY\n");
-		break;
+		return;
 
 	case L2_OP_ALLOC_NAMESPACE:
 		printf("ALLOC_NAMESPACE\n");
-		break;
+		return;
 
 	case L2_OP_ALLOC_FUNCTION:
 		printf("ALLOC_FUNCTION\n");
-		break;
+		return;
 
 	case L2_OP_NAMESPACE_SET:
 		printf("NAMESPACE_SET\n");
-		break;
+		return;
 
 	case L2_OP_NAMESPACE_LOOKUP:
 		printf("NAMESPACE_LOOKUP\n");
-		break;
+		return;
 
 	case L2_OP_DIRECT_ARRAY_LOOKUP:
 		printf("DIRECT_ARRAY_LOOKUP\n");
-		break;
+		return;
+
+	case L2_OP_DIRECT_ARRAY_SET:
+		printf("DIRECT_ARRAY_SET\n");
+		return;
 
 	case L2_OP_HALT:
 		printf("HALT\n");
-		break;
+		return;
+	}
 
-	default:
-		{
-			l2_word word = (l2_word)opcode;
-			char bytes[sizeof(word)];
-			memcpy(&bytes, &word, sizeof(word));
-			printf("?");
-			for (size_t i = 0; i < sizeof(bytes); ++i) {
-				printf(" %02x", bytes[i]);
-			}
-			printf("\n");
-		}
+	l2_word word = (l2_word)opcode;
+	char bytes[sizeof(word)];
+	memcpy(&bytes, &word, sizeof(word));
+	printf("?");
+	for (size_t i = 0; i < sizeof(bytes); ++i) {
+		printf(" %02x", bytes[i]);
 	}
+	printf("\n");
 }
 
 void l2_vm_print_bytecode(l2_word *ops, size_t opcount) {

lib/vm/vm.c

@@ -226,6 +226,11 @@ void l2_vm_step(struct l2_vm *vm) {
 		vm->sptr -= 1;
 		break;
 
+	case L2_OP_SWAP_POP:
+		vm->stack[vm->sptr - 2] = vm->stack[vm->sptr - 1];
+		vm->sptr -= 1;
+		break;
+
 	case L2_OP_DUP:
 		vm->stack[vm->sptr] = vm->ops[vm->sptr - 1];
 		vm->sptr += 1;
@@ -437,6 +442,16 @@ void l2_vm_step(struct l2_vm *vm) {
 		}
 		break;
 
+	case L2_OP_DIRECT_ARRAY_SET:
+		{
+			l2_word key = vm->stack[--vm->sptr];
+			l2_word val = vm->stack[vm->sptr - 1];
+			l2_word arr = vm->stack[vm->sptr - 2];
+			// TODO: Error if out of bounds or incorrect type
+			vm->values[arr].array->data[key] = val;
+		}
+		break;
+
 	case L2_OP_HALT:
 		break;
 	}