From efaeaa579b0fdee56fedcdcef6383304a30044f4 Mon Sep 17 00:00:00 2001
From: Sven Verdoolaege <skimo@kotnet.org>
Date: Wed, 13 May 2015 14:59:40 +0200
Subject: [PATCH] iscc: add equality operation on strings

This will allow us to implement a test for equality to NaN in terms
of strings.

Signed-off-by: Sven Verdoolaege <skimo@kotnet.org>
---
 doc/isl.tex |  2 ++
 iscc.c      | 12 ++++++++++++
 2 files changed, 14 insertions(+)

diff --git a/doc/isl.tex b/doc/isl.tex
index a0a3515..4c2f8f5 100644
--- a/doc/isl.tex
+++ b/doc/isl.tex
@@ -1023,6 +1023,8 @@ $b$ := $s_1$ \ai[\tt]{=} $s_2$ & is $s_1$ equal to $s_2$?
 \\
 $b$ := $m_1$ \ai[\tt]{=} $m_2$ & is $m_1$ equal to $m_2$?
 \\
+$b$ := $S_1$ \ai[\tt]{=} $S_2$ & is $S_1$ equal to $S_2$?
+\\
 $b$ := $s_1$ \ai[\tt]{<=} $s_2$ & is $s_1$ a subset of $s_2$?
 \\
 $b$ := $m_1$ \ai[\tt]{<=} $m_2$ & is $m_1$ a subset of $m_2$?
diff --git a/iscc.c b/iscc.c
index c045fb4..fff567f 100644
--- a/iscc.c
+++ b/iscc.c
@@ -381,6 +381,16 @@ int_val_mul_union_pw_qpolynomial_fold(__isl_take isl_val *v,
 	return isl_union_pw_qpolynomial_fold_scale_val(upwf, v);
 }
 
+/* Are the two strings "str1" and "str2" equal to each other?
+ */
+static int str_eq(__isl_keep isl_str *str1, __isl_keep isl_str *str2)
+{
+	if (!str1 || !str2)
+		return -1;
+
+	return !strcmp(str1->s, str2->s);
+}
+
 struct isc_bin_op bin_ops[] = {
 	{ '+',	isl_obj_val,	isl_obj_val, isl_obj_val,
 		(isc_bin_op_fn) &isl_val_add },
@@ -548,6 +558,8 @@ struct isc_bin_op bin_ops[] = {
 			    &isl_union_pw_qpolynomial_fold_plain_is_equal } },
 	{ '+',	isl_obj_str,	isl_obj_str,	isl_obj_str,
 		(isc_bin_op_fn) &isl_str_concat },
+	{ '=',	isl_obj_str,	isl_obj_str,	isl_obj_bool,
+		{ .test = (isc_bin_test_fn) &str_eq } },
 	0
 };
 
-- 
2.11.4.GIT