X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fopt%2Fconvopt.c;h=5ecf85e77a78ea125440b21ee8077714b1318cca;hb=dd4cd761ab637d4488c7e29f49843b1b02366acf;hp=3ee9687b854c5c8f0a439237eab0ab760203b747;hpb=3cd2c1a3415e590caec9051ec33fe9ca2b2ae4dc;p=libfirm

diff --git a/ir/opt/convopt.c b/ir/opt/convopt.c
index 3ee9687b8..5ecf85e77 100644
--- a/ir/opt/convopt.c
+++ b/ir/opt/convopt.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1995-2007 University of Karlsruhe.  All right reserved.
+ * Copyright (C) 1995-2008 University of Karlsruhe.  All right reserved.
  *
  * This file is part of libFirm.
  *
@@ -106,15 +106,18 @@ int get_conv_costs(const ir_node *node, ir_mode *dest_mode)
 		return conv_const_tv(node, dest_mode) == tarval_bad ? 1 : 0;
 	}
 
+	if (is_Conv(node) &&
+			is_downconv(mode, dest_mode) &&
+			get_irn_mode(get_Conv_op(node)) == dest_mode) {
+		return -1;
+	}
+
 	if (get_irn_n_edges(node) > 1) {
-		if (is_Conv(node) && is_downconv(get_irn_mode(node), dest_mode)) {
-			return get_conv_costs(get_Conv_op(node), dest_mode) - 1;
-		}
 		DB((dbg, LEVEL_3, "multi outs at %+F\n", node));
 		return 1;
 	}
 
-	if (is_Conv(node) && is_downconv(get_irn_mode(node), dest_mode)) {
+	if (is_Conv(node) && is_downconv(mode, dest_mode)) {
 		return get_conv_costs(get_Conv_op(node), dest_mode) - 1;
 	}
 
@@ -137,12 +140,13 @@ int get_conv_costs(const ir_node *node, ir_mode *dest_mode)
 	}
 #endif
 
-	if (!is_optimizable_node(node)) {
+	if (!mode_is_int(mode) || !is_optimizable_node(node)) {
 		return 1;
 	}
 
 	costs = 0;
-	arity = get_irn_arity(node);
+	// The shift count does not participate in the conv optimisation
+	arity = is_Shl(node) ? 1 : get_irn_arity(node);
 	for (i = 0; i < arity; ++i) {
 		ir_node *pred = get_irn_n(node, i);
 		costs += imin(get_conv_costs(pred, dest_mode), 1);
@@ -161,10 +165,11 @@ static ir_node *place_conv(ir_node *node, ir_mode *dest_mode)
 static
 ir_node *conv_transform(ir_node *node, ir_mode *dest_mode)
 {
-	size_t arity;
-	size_t i;
+	ir_mode *mode = get_irn_mode(node);
+	size_t   arity;
+	size_t   i;
 
-	if (get_irn_mode(node) == dest_mode)
+	if (mode == dest_mode)
 		return node;
 
 	if (is_Const(node)) {
@@ -177,22 +182,26 @@ ir_node *conv_transform(ir_node *node, ir_mode *dest_mode)
 		}
 	}
 
+	if (is_Conv(node) &&
+			is_downconv(mode, dest_mode) &&
+			get_irn_mode(get_Conv_op(node)) == dest_mode) {
+		return get_Conv_op(node);
+	}
+
 	if (get_irn_n_edges(node) > 1) {
-		if (is_Conv(node) && is_downconv(get_irn_mode(node), dest_mode)) {
-			return conv_transform(get_Conv_op(node), dest_mode);
-		}
 		return place_conv(node, dest_mode);
 	}
 
-	if (is_Conv(node) && is_downconv(get_irn_mode(node), dest_mode)) {
+	if (is_Conv(node) && is_downconv(mode, dest_mode)) {
 		return conv_transform(get_Conv_op(node), dest_mode);
 	}
 
-	if (!is_optimizable_node(node)) {
+	if (!mode_is_int(mode) || !is_optimizable_node(node)) {
 		return place_conv(node, dest_mode);
 	}
 
-	arity = get_irn_arity(node);
+	// The shift count does not participate in the conv optimisation
+	arity = is_Shl(node) ? 1 : get_irn_arity(node);
 	for (i = 0; i < arity; i++) {
 		ir_node *pred = get_irn_n(node, i);
 		ir_node *transformed;
@@ -247,6 +256,9 @@ void conv_opt_walker(ir_node *node, void *data)
 	mode      = get_irn_mode(node);
 	pred_mode = get_irn_mode(pred);
 
+	if (mode_is_reference(mode) || mode_is_reference(pred_mode))
+		return;
+
 	if (!is_Phi(pred) && !is_downconv(pred_mode, mode))
 		return;