From 0e00b23c2195956fbaf988255422d2a463095357 Mon Sep 17 00:00:00 2001
From: Sven Verdoolaege <skimo@kotnet.org>
Date: Thu, 2 Jun 2011 14:12:03 +0200
Subject: [PATCH] add isl_aff_scale and isl_aff_scale_down

Signed-off-by: Sven Verdoolaege <skimo@kotnet.org>
---
 doc/user.pod      |  4 ++++
 include/isl/aff.h |  3 +++
 isl_aff.c         | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 56 insertions(+)

diff --git a/doc/user.pod b/doc/user.pod
index 9a345c7a..72f93fdf 100644
--- a/doc/user.pod
+++ b/doc/user.pod
@@ -2126,6 +2126,10 @@ Operations include
 		__isl_take isl_aff *aff2);
 	__isl_give isl_aff *isl_aff_neg(__isl_take isl_aff *aff);
 	__isl_give isl_aff *isl_aff_ceil(__isl_take isl_aff *aff);
+	__isl_give isl_aff *isl_aff_scale(__isl_take isl_aff *aff,
+		isl_int f);
+	__isl_give isl_aff *isl_aff_scale_down(__isl_take isl_aff *aff,
+		isl_int f);
 
 An expression can be printed using
 
diff --git a/include/isl/aff.h b/include/isl/aff.h
index 80836eb6..b01ff299 100644
--- a/include/isl/aff.h
+++ b/include/isl/aff.h
@@ -51,6 +51,9 @@ __isl_give isl_aff *isl_aff_add(__isl_take isl_aff *aff1,
 __isl_give isl_aff *isl_aff_sub(__isl_take isl_aff *aff1,
 	__isl_take isl_aff *aff2);
 
+__isl_give isl_aff *isl_aff_scale(__isl_take isl_aff *aff, isl_int f);
+__isl_give isl_aff *isl_aff_scale_down(__isl_take isl_aff *aff, isl_int f);
+
 __isl_give isl_printer *isl_printer_print_aff(__isl_take isl_printer *p,
 	__isl_keep isl_aff *aff);
 void isl_aff_dump(__isl_keep isl_aff *aff);
diff --git a/isl_aff.c b/isl_aff.c
index fe07d4a9..75b1c203 100644
--- a/isl_aff.c
+++ b/isl_aff.c
@@ -513,3 +513,52 @@ __isl_give isl_aff *isl_aff_sub(__isl_take isl_aff *aff1,
 {
 	return isl_aff_add(aff1, isl_aff_neg(aff2));
 }
+
+__isl_give isl_aff *isl_aff_scale(__isl_take isl_aff *aff, isl_int f)
+{
+	isl_int gcd;
+
+	if (isl_int_is_one(f))
+		return aff;
+
+	aff = isl_aff_cow(aff);
+	if (!aff)
+		return NULL;
+	aff->v = isl_vec_cow(aff->v);
+	if (!aff->v)
+		return isl_aff_free(aff);
+
+	isl_int_init(gcd);
+	isl_int_gcd(gcd, aff->v->el[0], f);
+	isl_int_divexact(aff->v->el[0], aff->v->el[0], gcd);
+	isl_int_divexact(gcd, f, gcd);
+	isl_seq_scale(aff->v->el + 1, aff->v->el + 1, gcd, aff->v->size - 1);
+	isl_int_clear(gcd);
+
+	return aff;
+}
+
+__isl_give isl_aff *isl_aff_scale_down(__isl_take isl_aff *aff, isl_int f)
+{
+	isl_int gcd;
+
+	if (isl_int_is_one(f))
+		return aff;
+
+	aff = isl_aff_cow(aff);
+	if (!aff)
+		return NULL;
+	aff->v = isl_vec_cow(aff->v);
+	if (!aff->v)
+		return isl_aff_free(aff);
+
+	isl_int_init(gcd);
+	isl_seq_gcd(aff->v->el + 1, aff->v->size - 1, &gcd);
+	isl_int_gcd(gcd, gcd, f);
+	isl_seq_scale_down(aff->v->el + 1, aff->v->el + 1, gcd, aff->v->size - 1);
+	isl_int_divexact(gcd, f, gcd);
+	isl_int_mul(aff->v->el[0], aff->v->el[0], gcd);
+	isl_int_clear(gcd);
+
+	return aff;
+}
-- 
2.11.4.GIT