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/* Simple expression parser */%{#include "util.h"#include "util/debug.h"#define IN_EXPR_Y 1#include "expr.h"#include "smt.h"#include <string.h> #define MAXIDLEN 256%} %pure-parser%parse-param { double *final_val }%parse-param { struct parse_ctx *ctx }%parse-param { const char **pp }%lex-param { const char **pp } %union {	double num;	char id[MAXIDLEN+1];} %token <num> NUMBER%token <id> ID%token MIN MAX IF ELSE SMT_ON%left MIN MAX IF%left '|'%left '^'%left '&'%left '-' '+'%left '*' '/' '%'%left NEG NOT%type <num> expr if_expr %{static int expr__lex(YYSTYPE *res, const char **pp); static void expr__error(double *final_val __maybe_unused,		       struct parse_ctx *ctx __maybe_unused,		       const char **pp __maybe_unused,		       const char *s){	pr_debug("%s\n", s);} static int lookup_id(struct parse_ctx *ctx, char *id, double *val){	int i; 	for (i = 0; i < ctx->num_ids; i++) {		if (!strcasecmp(ctx->ids[i].name, id)) {			*val = ctx->ids[i].val;			return 0;		}	}	return -1;} %}%% all_expr: if_expr			{ *final_val = $1; }	; if_expr:	expr IF expr ELSE expr { $$ = $3 ? $1 : $5; }	| expr	; expr:	  NUMBER	| ID			{ if (lookup_id(ctx, $1, &$$) < 0) {					pr_debug("%s not found\n", $1);					YYABORT;				  }				}	| expr '|' expr		{ $$ = (long)$1 | (long)$3; }	| expr '&' expr		{ $$ = (long)$1 & (long)$3; }	| expr '^' expr		{ $$ = (long)$1 ^ (long)$3; }	| expr '+' expr		{ $$ = $1 + $3; }	| expr '-' expr		{ $$ = $1 - $3; }	| expr '*' expr		{ $$ = $1 * $3; }	| expr '/' expr		{ if ($3 == 0) YYABORT; $$ = $1 / $3; }	| expr '%' expr		{ if ((long)$3 == 0) YYABORT; $$ = (long)$1 % (long)$3; }	| '-' expr %prec NEG	{ $$ = -$2; }	| '(' if_expr ')'	{ $$ = $2; }	| MIN '(' expr ',' expr ')' { $$ = $3 < $5 ? $3 : $5; }	| MAX '(' expr ',' expr ')' { $$ = $3 > $5 ? $3 : $5; }	| SMT_ON		 { $$ = smt_on() > 0; }	; %% static int expr__symbol(YYSTYPE *res, const char *p, const char **pp){	char *dst = res->id;	const char *s = p; 	if (*p == '#')		*dst++ = *p++; 	while (isalnum(*p) || *p == '_' || *p == '.' || *p == ':' || *p == '@' || *p == '\\') {		if (p - s >= MAXIDLEN)			return -1;		/*		 * Allow @ instead of / to be able to specify pmu/event/ without		 * conflicts with normal division.		 */		if (*p == '@')			*dst++ = '/';		else if (*p == '\\')			*dst++ = *++p;		else			*dst++ = *p;		p++;	}	*dst = 0;	*pp = p;	dst = res->id;	switch (dst[0]) {	case 'm':		if (!strcmp(dst, "min"))			return MIN;		if (!strcmp(dst, "max"))			return MAX;		break;	case 'i':		if (!strcmp(dst, "if"))			return IF;		break;	case 'e':		if (!strcmp(dst, "else"))			return ELSE;		break;	case '#':		if (!strcasecmp(dst, "#smt_on"))			return SMT_ON;		break;	}	return ID;} static int expr__lex(YYSTYPE *res, const char **pp){	int tok;	const char *s;	const char *p = *pp; 	while (isspace(*p))		p++;	s = p;	switch (*p++) {	case '#':	case 'a' ... 'z':	case 'A' ... 'Z':		return expr__symbol(res, p - 1, pp);	case '0' ... '9': case '.':		res->num = strtod(s, (char **)&p);		tok = NUMBER;		break;	default:		tok = *s;		break;	}	*pp = p;	return tok;} /* Caller must make sure id is allocated */void expr__add_id(struct parse_ctx *ctx, const char *name, double val){	int idx;	assert(ctx->num_ids < MAX_PARSE_ID);	idx = ctx->num_ids++;	ctx->ids[idx].name = name;	ctx->ids[idx].val = val;} void expr__ctx_init(struct parse_ctx *ctx){	ctx->num_ids = 0;} static bool already_seen(const char *val, const char *one, const char **other,			 int num_other){	int i; 	if (one && !strcasecmp(one, val))		return true;	for (i = 0; i < num_other; i++)		if (!strcasecmp(other[i], val))			return true;	return false;} int expr__find_other(const char *p, const char *one, const char ***other,		     int *num_otherp){	const char *orig = p;	int err = -1;	int num_other; 	*other = malloc((EXPR_MAX_OTHER + 1) * sizeof(char *));	if (!*other)		return -1; 	num_other = 0;	for (;;) {		YYSTYPE val;		int tok = expr__lex(&val, &p);		if (tok == 0) {			err = 0;			break;		}		if (tok == ID && !already_seen(val.id, one, *other, num_other)) {			if (num_other >= EXPR_MAX_OTHER - 1) {				pr_debug("Too many extra events in %s\n", orig);				break;			}			(*other)[num_other] = strdup(val.id);			if (!(*other)[num_other])				return -1;			num_other++;		}	}	(*other)[num_other] = NULL;	*num_otherp = num_other;	if (err) {		*num_otherp = 0;		free(*other);		*other = NULL;	}	return err;}