1/* Simple expression parser */
  2%{
  3#define YYDEBUG 1
  4#include <stdio.h>
  5#include "util.h"
  6#include "util/debug.h"
  7#include <stdlib.h> // strtod()
  8#define IN_EXPR_Y 1
  9#include "expr.h"
 10#include "smt.h"
 11#include <string.h>
 12
 13static double d_ratio(double val0, double val1)
 14{
 15	if (val1 == 0) {
 16		return 0;
 17	}
 18	return  val0 / val1;
 19}
 20
 21%}
 22
 23%define api.pure full
 24
 25%parse-param { double *final_val }
 26%parse-param { struct expr_parse_ctx *ctx }
 27%parse-param {void *scanner}
 28%lex-param {void* scanner}
 29
 30%union {
 31	double	 num;
 32	char	*str;
 33}
 34
 35%token EXPR_PARSE EXPR_OTHER EXPR_ERROR
 36%token <num> NUMBER
 37%token <str> ID
 38%destructor { free ($$); } <str>
 39%token MIN MAX IF ELSE SMT_ON D_RATIO
 40%left MIN MAX IF
 41%left '|'
 42%left '^'
 43%left '&'
 44%left '<' '>'
 45%left '-' '+'
 46%left '*' '/' '%'
 47%left NEG NOT
 48%type <num> expr if_expr
 49
 50%{
 51static void expr_error(double *final_val __maybe_unused,
 52		       struct expr_parse_ctx *ctx __maybe_unused,
 53		       void *scanner,
 54		       const char *s)
 55{
 56	pr_debug("%s\n", s);
 57}
 58
 59%}
 60%%
 61
 62start:
 63EXPR_PARSE all_expr
 64|
 65EXPR_OTHER all_other
 66
 67all_other: all_other other
 68|
 69
 70other: ID
 71{
 72	expr__add_id(ctx, $1);
 73}
 74|
 75MIN | MAX | IF | ELSE | SMT_ON | NUMBER | '|' | '^' | '&' | '-' | '+' | '*' | '/' | '%' | '(' | ')' | ','
 76|
 77'<' | '>' | D_RATIO
 78
 79all_expr: if_expr			{ *final_val = $1; }
 80	;
 81
 82if_expr:
 83	expr IF expr ELSE expr { $$ = $3 ? $1 : $5; }
 84	| expr
 85	;
 86
 87expr:	  NUMBER
 88	| ID			{
 89					struct expr_id_data *data;
 90
 91					if (expr__resolve_id(ctx, $1, &data)) {
 92						free($1);
 93						YYABORT;
 94					}
 95
 96					$$ = expr_id_data__value(data);
 97					free($1);
 98				}
 99	| expr '|' expr		{ $$ = (long)$1 | (long)$3; }
100	| expr '&' expr		{ $$ = (long)$1 & (long)$3; }
101	| expr '^' expr		{ $$ = (long)$1 ^ (long)$3; }
102	| expr '<' expr		{ $$ = $1 < $3; }
103	| expr '>' expr		{ $$ = $1 > $3; }
104	| expr '+' expr		{ $$ = $1 + $3; }
105	| expr '-' expr		{ $$ = $1 - $3; }
106	| expr '*' expr		{ $$ = $1 * $3; }
107	| expr '/' expr		{ if ($3 == 0) {
108					pr_debug("division by zero\n");
109					YYABORT;
110				  }
111				  $$ = $1 / $3;
112	                        }
113	| expr '%' expr		{ if ((long)$3 == 0) {
114					pr_debug("division by zero\n");
115					YYABORT;
116				  }
117				  $$ = (long)$1 % (long)$3;
118	                        }
119	| '-' expr %prec NEG	{ $$ = -$2; }
120	| '(' if_expr ')'	{ $$ = $2; }
121	| MIN '(' expr ',' expr ')' { $$ = $3 < $5 ? $3 : $5; }
122	| MAX '(' expr ',' expr ')' { $$ = $3 > $5 ? $3 : $5; }
123	| SMT_ON		 { $$ = smt_on() > 0; }
124	| D_RATIO '(' expr ',' expr ')' { $$ = d_ratio($3,$5); }
125	;
126
127%%