From: Sven Verdoolaege <skimo@kotnet.org>
Date: Sat, 11 Jul 2009 13:15:26 +0000 (+0200)
Subject: isl_tab: optionally save dual solution
X-Git-Tag: isl-0.01~156
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=f67c8d827f8f5d394962bb9cc8f4b6bbb992e1e1;p=platform%2Fupstream%2Fisl.git

isl_tab: optionally save dual solution
---

diff --git a/isl_convex_hull.c b/isl_convex_hull.c
index 3912cbf..caa1c0b 100644
--- a/isl_convex_hull.c
+++ b/isl_convex_hull.c
@@ -2109,7 +2109,7 @@ static int is_bound(struct sh_data *data, struct isl_set *set, int j,
 	isl_int_init(opt);
 
 	res = isl_tab_min(data->ctx, data->p[j].tab, ineq, data->ctx->one,
-				&opt, NULL);
+				&opt, NULL, 0);
 	if (res == isl_lp_ok && isl_int_is_neg(opt))
 		isl_int_sub(ineq[0], ineq[0], opt);
 
diff --git a/isl_lp.c b/isl_lp.c
index 559a4b5..9f8c314 100644
--- a/isl_lp.c
+++ b/isl_lp.c
@@ -17,7 +17,7 @@ enum isl_lp_result isl_tab_solve_lp(struct isl_basic_map *bmap, int maximize,
 
 	bmap = isl_basic_map_gauss(bmap, NULL);
 	tab = isl_tab_from_basic_map(bmap);
-	res = isl_tab_min(bmap->ctx, tab, f, bmap->ctx->one, opt, opt_denom);
+	res = isl_tab_min(bmap->ctx, tab, f, bmap->ctx->one, opt, opt_denom, 0);
 	isl_tab_free(bmap->ctx, tab);
 
 	if (maximize)
diff --git a/isl_map_simplify.c b/isl_map_simplify.c
index abc7695..b797b5e 100644
--- a/isl_map_simplify.c
+++ b/isl_map_simplify.c
@@ -2059,7 +2059,7 @@ static struct isl_basic_map *drop_more_redundant_divs(
 				construct_test_ineq(bmap, i, l, u,
 						    vec->el, g, fl, fu);
 				res = isl_tab_min(ctx, tab, vec->el,
-						  ctx->one, &g, NULL);
+						  ctx->one, &g, NULL, 0);
 				if (res == isl_lp_error)
 					goto error;
 				if (res == isl_lp_empty) {
diff --git a/isl_tab.c b/isl_tab.c
index 579bac6..ac9310a 100644
--- a/isl_tab.c
+++ b/isl_tab.c
@@ -115,6 +115,7 @@ void isl_tab_free(struct isl_ctx *ctx, struct isl_tab *tab)
 		return;
 	free_undo(ctx, tab);
 	isl_mat_free(ctx, tab->mat);
+	isl_vec_free(tab->dual);
 	free(tab->var);
 	free(tab->con);
 	free(tab->row_var);
@@ -1547,7 +1548,8 @@ int isl_tab_is_equality(struct isl_ctx *ctx, struct isl_tab *tab, int con)
  * minmimal value returned in *opt).
  */
 enum isl_lp_result isl_tab_min(struct isl_ctx *ctx, struct isl_tab *tab,
-	isl_int *f, isl_int denom, isl_int *opt, isl_int *opt_denom)
+	isl_int *f, isl_int denom, isl_int *opt, isl_int *opt_denom,
+	unsigned flags)
 {
 	int r;
 	enum isl_lp_result res = isl_lp_ok;
@@ -1575,6 +1577,24 @@ enum isl_lp_result isl_tab_min(struct isl_ctx *ctx, struct isl_tab *tab,
 	}
 	if (drop_row(ctx, tab, var->index) < 0)
 		return isl_lp_error;
+	if (ISL_FL_ISSET(flags, ISL_TAB_SAVE_DUAL)) {
+		int i;
+
+		isl_vec_free(tab->dual);
+		tab->dual = isl_vec_alloc(ctx, 1 + tab->n_con);
+		if (!tab->dual)
+			return isl_lp_error;
+		isl_int_set(tab->dual->el[0], tab->mat->row[var->index][0]);
+		for (i = 0; i < tab->n_con; ++i) {
+			if (tab->con[i].is_row)
+				isl_int_set_si(tab->dual->el[1 + i], 0);
+			else {
+				int pos = 2 + tab->con[i].index;
+				isl_int_set(tab->dual->el[1 + i],
+					    tab->mat->row[var->index][pos]);
+			}
+		}
+	}
 	if (res == isl_lp_ok) {
 		if (opt_denom) {
 			isl_int_set(*opt, tab->mat->row[var->index][1]);
diff --git a/isl_tab.h b/isl_tab.h
index b9a9810..1df42e1 100644
--- a/isl_tab.h
+++ b/isl_tab.h
@@ -88,6 +88,8 @@ struct isl_tab {
 	struct isl_tab_undo bottom;
 	struct isl_tab_undo *top;
 
+	struct isl_vec *dual;
+
 	unsigned need_undo : 1;
 	unsigned rational : 1;
 	unsigned empty : 1;
@@ -109,8 +111,10 @@ struct isl_tab *isl_tab_detect_equalities(struct isl_ctx *ctx,
 				struct isl_tab *tab);
 struct isl_tab *isl_tab_detect_redundant(struct isl_ctx *ctx,
 				struct isl_tab *tab);
+#define ISL_TAB_SAVE_DUAL	(1 << 0)
 enum isl_lp_result isl_tab_min(struct isl_ctx *ctx, struct isl_tab *tab,
-	isl_int *f, isl_int denom, isl_int *opt, isl_int *opt_denom);
+	isl_int *f, isl_int denom, isl_int *opt, isl_int *opt_denom,
+	unsigned flags);
 
 struct isl_tab *isl_tab_extend(struct isl_ctx *ctx, struct isl_tab *tab,
 				unsigned n_new);