asm: adding AST

src/as/ast.h

@@ -0,0 +1,81 @@
+/* ast.h
+ *
+ *   Copyright (C) 2018   Henrik Hautakoski <henrik.hautakoski@gmail.com>
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ *   MA 02110-1301, USA.
+ */
+#ifndef ASM_AST_H
+#define ASM_AST_H
+
+#include <vector.h>
+#include "symtab.h"
+
+// All datatypes in the language.
+enum ast_datatype {
+	DATATYPE_NONE = 0,   // Not an actual type.
+	DATATYPE_REGISTER,   // 4 bit unsigned.
+	DATATYPE_NUMBER,     // 8 bit signed.
+	DATATYPE_STRING
+};
+
+// Struct to represent a single operand to a instruction.
+struct ast_instr_operand {
+	enum ast_datatype type;
+	union {
+		uint8_t     r;
+		int8_t      n;
+		uint16_t    addr;
+		const char *s;
+	};
+};
+
+// Struct to represent a single instruction.
+struct ast_instr {
+	uint8_t opcode;
+	uint8_t n_operands;
+	struct ast_instr_operand operands[3];
+};
+
+// Structure to represent a program.
+struct ast {
+
+	// List of instructions.
+	struct vector instr;
+
+	// List for storing label pointers (so we can free)
+	struct vector labels;
+
+	// Symbol table with label - location mapping.
+	symtab_t *symbols;
+};
+
+void ast_init(struct ast* ast);
+
+void ast_free(struct ast* ast);
+
+// Add an instruction
+void ast_instr(struct ast* ast, uint8_t opcode);
+
+// Add an operand to the latest instruction.
+//void ast_instr_operand(struct ast* ast, const struct ast_instr_operand* op);
+void ast_instr_operand(struct ast* ast, enum ast_datatype type, void* value);
+
+void ast_location(struct ast* ast, const char *label, uint16_t loc);
+
+// For debugging :)
+void ast_print(struct ast* ast);
+
+#endif /* ASM_AST_H */