expression.h

/*
   Kafel - expression
   -----------------------------------------

   Copyright 2016 Google Inc. All Rights Reserved.

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

     http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.

*/

#ifndef KAFEL_EXPRESSION_H
#define KAFEL_EXPRESSION_H

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

enum {
  EXPR_LEAF_MIN,
  EXPR_NUMBER = EXPR_LEAF_MIN,
  EXPR_VAR,
  EXPR_TRUE,
  EXPR_FALSE,
  EXPR_LEAF_MAX = EXPR_FALSE,
  EXPR_UNARY_MIN,
  EXPR_NOT = EXPR_UNARY_MIN,
  EXPR_UNARY_MAX = EXPR_NOT,
  EXPR_BINARY_MIN,
  EXPR_AND = EXPR_BINARY_MIN,
  EXPR_OR,
  EXPR_GT,
  EXPR_LT,
  EXPR_GE,
  EXPR_LE,
  EXPR_EQ,
  EXPR_NEQ,
  EXPR_BIT_AND,
  EXPR_BINARY_MAX = EXPR_BIT_AND,
  EXPR_MAX = EXPR_BINARY_MAX,
};

struct expr_tree {
  int type;
  union {
    struct {
      int var;
      int size;
    };
    uint64_t number;
    struct expr_tree *child;
    struct {
      struct expr_tree *left;
      struct expr_tree *right;
    };
  };
};

struct expr_tree *expr_create_number(uint64_t value);
struct expr_tree *expr_create_var(int var, int size);
struct expr_tree *expr_create_unary(int op, struct expr_tree *child);
struct expr_tree *expr_create_binary(int op, struct expr_tree *left,
                                     struct expr_tree *right);
void expr_negate(struct expr_tree **expr);
void expr_eliminate_negation(struct expr_tree **expr, bool neg);
void expr_simplify(struct expr_tree **expr);
void expr_destroy(struct expr_tree **expr);

#endif /* KAFEL_EXPRESSION_H */