mergesort: avoid cloning value in expr_msort_cmp()

If we have a plain EXPR_VALUE value, there is no need to copy
it via mpz_set().

Signed-off-by: Thomas Haller <thaller@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/src/mergesort.c b/src/mergesort.c
index 5965236af6b7bd80f6a0f95a99af7aef243d9e42..4d0e280fdc5e22cf07021388a48a239c9a4ef982 100644 (file)
--- a/src/mergesort.c
+++ b/src/mergesort.c
@@ -12,8 +12,6 @@
 #include <gmputil.h>
 #include <list.h>
 
-static void expr_msort_value(const struct expr *expr, mpz_t value);
-
 static void concat_expr_msort_value(const struct expr *expr, mpz_t value)
 {
        unsigned int len = 0, ilen;
@@ -29,20 +27,17 @@ static void concat_expr_msort_value(const struct expr *expr, mpz_t value)
        mpz_import_data(value, data, BYTEORDER_HOST_ENDIAN, len);
 }
 
-static void expr_msort_value(const struct expr *expr, mpz_t value)
+static mpz_srcptr expr_msort_value(const struct expr *expr, mpz_t value)
 {
        switch (expr->etype) {
        case EXPR_SET_ELEM:
-               expr_msort_value(expr->key, value);
-               break;
+               return expr_msort_value(expr->key, value);
        case EXPR_BINOP:
        case EXPR_MAPPING:
        case EXPR_RANGE:
-               expr_msort_value(expr->left, value);
-               break;
+               return expr_msort_value(expr->left, value);
        case EXPR_VALUE:
-               mpz_set(value, expr->value);
-               break;
+               return expr->value;
        case EXPR_CONCAT:
                concat_expr_msort_value(expr, value);
                break;
@@ -53,20 +48,24 @@ static void expr_msort_value(const struct expr *expr, mpz_t value)
        default:
                BUG("Unknown expression %s\n", expr_name(expr));
        }
+       return value;
 }
 
 static int expr_msort_cmp(const struct expr *e1, const struct expr *e2)
 {
-       mpz_t value1, value2;
+       mpz_srcptr value1;
+       mpz_srcptr value2;
+       mpz_t value1_tmp;
+       mpz_t value2_tmp;
        int ret;
 
-       mpz_init(value1);
-       mpz_init(value2);
-       expr_msort_value(e1, value1);
-       expr_msort_value(e2, value2);
+       mpz_init(value1_tmp);
+       mpz_init(value2_tmp);
+       value1 = expr_msort_value(e1, value1_tmp);
+       value2 = expr_msort_value(e2, value2_tmp);
        ret = mpz_cmp(value1, value2);
-       mpz_clear(value1);
-       mpz_clear(value2);
+       mpz_clear(value1_tmp);
+       mpz_clear(value2_tmp);
 
        return ret;
 }