include/parse.h

/*
 * *****************************************************************************
 *
 * Copyright 2018 Gavin D. Howard
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
 * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 * PERFORMANCE OF THIS SOFTWARE.
 *
 * *****************************************************************************
 *
 * Definitions for bc's parser.
 *
 */

#ifndef BC_PARSE_H
#define BC_PARSE_H

#include <stdbool.h>
#include <stdint.h>

#include <status.h>
#include <vector.h>
#include <program.h>
#include <lex.h>

#define BC_PARSE_TOP_FLAG_PTR(parse)  ((uint8_t*) bc_vec_top(&(parse)->flags))

#define BC_PARSE_TOP_FLAG(parse)  (*(BC_PARSE_TOP_FLAG_PTR(parse)))

#define BC_PARSE_FLAG_FUNC_INNER (0x01)

#define BC_PARSE_FUNC_INNER(parse)  \
  (BC_PARSE_TOP_FLAG(parse) & BC_PARSE_FLAG_FUNC_INNER)

#define BC_PARSE_FLAG_FUNC (0x02)

#define BC_PARSE_FUNC(parse)  \
  (BC_PARSE_TOP_FLAG(parse) & BC_PARSE_FLAG_FUNC)

#define BC_PARSE_FLAG_BODY (0x04)

#define BC_PARSE_BODY(parse)  \
  (BC_PARSE_TOP_FLAG(parse) & BC_PARSE_FLAG_BODY)

#define BC_PARSE_FLAG_LOOP (0x08)

#define BC_PARSE_LOOP(parse)  \
  (BC_PARSE_TOP_FLAG(parse) & BC_PARSE_FLAG_LOOP)

#define BC_PARSE_FLAG_LOOP_INNER (0x10)

#define BC_PARSE_LOOP_INNER(parse) \
  (BC_PARSE_TOP_FLAG(parse) & BC_PARSE_FLAG_LOOP_INNER)

#define BC_PARSE_FLAG_IF (0x20)

#define BC_PARSE_IF(parse)  \
  (BC_PARSE_TOP_FLAG(parse) & BC_PARSE_FLAG_IF)

#define BC_PARSE_FLAG_ELSE (0x40)

#define BC_PARSE_ELSE(parse)  \
  (BC_PARSE_TOP_FLAG(parse) & BC_PARSE_FLAG_ELSE)

#define BC_PARSE_FLAG_IF_END (0x80)

#define BC_PARSE_IF_END(parse)  \
  (BC_PARSE_TOP_FLAG(parse) & BC_PARSE_FLAG_IF_END)

#define BC_PARSE_CAN_EXEC(parse)  \
  (!(BC_PARSE_TOP_FLAG(parse) & (BC_PARSE_FLAG_FUNC_INNER |  \
                                 BC_PARSE_FLAG_FUNC |        \
                                 BC_PARSE_FLAG_BODY |  \
                                 BC_PARSE_FLAG_LOOP |        \
                                 BC_PARSE_FLAG_LOOP_INNER |  \
                                 BC_PARSE_FLAG_IF |          \
                                 BC_PARSE_FLAG_ELSE |        \
                                 BC_PARSE_FLAG_IF_END)))

// We can calculate the conversion between tokens and exprs
// by subtracting the position of the first operator in the
// lex enum and adding the position of the first in the expr
// enum. Note: This only works for binary operators.
#define BC_PARSE_TOKEN_TO_EXPR(type) ((type) - BC_LEX_OP_POWER + BC_EXPR_POWER)

typedef struct BcOp {

  uint8_t prec;
  bool left;

} BcOp;

typedef struct BcParse {

  BcLex lex;
  BcLexToken token;

  BcVec flags;

  BcVec exit_labels;

  BcVec cond_labels;

  BcVec ops;

  BcProgram *program;
  size_t func;

  uint32_t num_braces;

  bool auto_part;

} BcParse;

#define BC_PARSE_EXPR_POSIX_REL (1<<0)
#define BC_PARSE_EXPR_PRINT (1<<1)
#define BC_PARSE_EXPR_NO_CALL (1<<2)
#define BC_PARSE_EXPR_NO_READ (1<<3)

// ** Exclude start. **
BcStatus bc_parse_init(BcParse *parse, BcProgram *program);

BcStatus bc_parse_parse(BcParse *parse);

void bc_parse_free(BcParse *parse);
// ** Exclude end. **

BcStatus bc_parse_expr(BcParse *parse, BcVec *code, uint8_t flags);

extern const bool bc_parse_token_exprs[];
extern const BcOp bc_parse_ops[];
extern const uint8_t bc_parse_insts[];

#endif // BC_PARSE_H