From: Sven Verdoolaege <skimo@kotnet.org>
Date: Wed, 5 Jun 2013 12:21:53 +0000 (+0200)
Subject: add isl_ast_expr_is_equal
X-Git-Tag: isl-0.13~151
X-Git-Url: https://repo.or.cz/w/isl.git/commitdiff_plain/fdcc255ef99121c49a1e02cbe1d7082f4a7416c3

add isl_ast_expr_is_equal

Signed-off-by: Sven Verdoolaege <skimo@kotnet.org>
---

diff --git a/doc/user.pod b/doc/user.pod
index 5b6cc36b..c4601ee2 100644
--- a/doc/user.pod
+++ b/doc/user.pod
@@ -5994,6 +5994,14 @@ Return the identifier represented by the AST expression.
 
 Return the integer represented by the AST expression.
 
+=head3 Properties of ASTs
+
+	#include <isl/ast.h>
+	int isl_ast_expr_is_equal(__isl_keep isl_ast_expr *expr1,
+		__isl_keep isl_ast_expr *expr2);
+
+Check if two C<isl_ast_expr>s are equal to each other.
+
 =head3 Manipulating and printing the AST
 
 AST nodes can be copied and freed using the following functions.
diff --git a/include/isl/ast.h b/include/isl/ast.h
index 5ac28ed7..76f1d38e 100644
--- a/include/isl/ast.h
+++ b/include/isl/ast.h
@@ -96,6 +96,9 @@ int isl_ast_expr_get_op_n_arg(__isl_keep isl_ast_expr *expr);
 __isl_give isl_ast_expr *isl_ast_expr_get_op_arg(__isl_keep isl_ast_expr *expr,
 	int pos);
 
+int isl_ast_expr_is_equal(__isl_keep isl_ast_expr *expr1,
+	__isl_keep isl_ast_expr *expr2);
+
 __isl_give isl_printer *isl_printer_print_ast_expr(__isl_take isl_printer *p,
 	__isl_keep isl_ast_expr *expr);
 void isl_ast_expr_dump(__isl_keep isl_ast_expr *expr);
diff --git a/isl_ast.c b/isl_ast.c
index 4e294fe2..b52041f5 100644
--- a/isl_ast.c
+++ b/isl_ast.c
@@ -1,3 +1,12 @@
+/*
+ * Copyright 2012-2013 Ecole Normale Superieure
+ *
+ * Use of this software is governed by the MIT license
+ *
+ * Written by Sven Verdoolaege,
+ * Ecole Normale Superieure, 45 rue d’Ulm, 75230 Paris, France
+ */
+
 #include <isl_ast_private.h>
 
 #undef BASE
@@ -312,6 +321,44 @@ error:
 	return isl_ast_expr_free(expr);
 }
 
+/* Is "expr1" equal to "expr2"?
+ */
+int isl_ast_expr_is_equal(__isl_keep isl_ast_expr *expr1,
+	__isl_keep isl_ast_expr *expr2)
+{
+	int i;
+
+	if (!expr1 || !expr2)
+		return -1;
+
+	if (expr1 == expr2)
+		return 1;
+	if (expr1->type != expr2->type)
+		return 0;
+	switch (expr1->type) {
+	case isl_ast_expr_int:
+		return isl_val_eq(expr1->u.v, expr2->u.v);
+	case isl_ast_expr_id:
+		return expr1->u.id == expr2->u.id;
+	case isl_ast_expr_op:
+		if (expr1->u.op.op != expr2->u.op.op)
+			return 0;
+		if (expr1->u.op.n_arg != expr2->u.op.n_arg)
+			return 0;
+		for (i = 0; i < expr1->u.op.n_arg; ++i) {
+			int equal;
+			equal = isl_ast_expr_is_equal(expr1->u.op.args[i],
+							expr2->u.op.args[i]);
+				return 0;
+			if (equal < 0 || !equal)
+				return equal;
+		}
+		return 1;
+	case isl_ast_expr_error:
+		return -1;
+	}
+}
+
 /* Create a new operation expression of operation type "op",
  * with "n_arg" as yet unspecified arguments.
  */