X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fir%2Fircons.c;h=f38994b2827e0098a139b6e027f10b64c1934b22;hb=eb47aca33f2f8c414409f3695e73277b47442334;hp=9a166e6133b6a87688f94775e74f6e2a0b9ef6cf;hpb=993b16f03ef90b6a6dc60ed0c68986cf1cd3571c;p=libfirm

diff --git a/ir/ir/ircons.c b/ir/ir/ircons.c
index 9a166e613..f38994b28 100644
--- a/ir/ir/ircons.c
+++ b/ir/ir/ircons.c
@@ -245,6 +245,8 @@ static ir_node *set_phi_arguments(ir_node *phi, int pos)
 		if (is_Bad(cfgpred)) {
 			value = new_r_Bad(irg);
 		} else {
+			inc_irg_visited(irg);
+
 			value = get_r_value_internal(cfgpred, pos, mode);
 		}
 		in[i] = value;
@@ -277,10 +279,17 @@ static ir_node *set_phi_arguments(ir_node *phi, int pos)
  */
 static ir_node *get_r_value_internal(ir_node *block, int pos, ir_mode *mode)
 {
-	ir_node *res = block->attr.block.graph_arr[pos];
+	ir_node  *res = block->attr.block.graph_arr[pos];
+	ir_graph *irg = get_irn_irg(block);
 	if (res != NULL)
 		return res;
 
+	/* We ran into a cycle. This may happen in unreachable loops. */
+	if (irn_visited_else_mark(block)) {
+		/* Since the loop is unreachable, return a Bad. */
+		return new_r_Bad(irg);
+	}
+
 	/* in a matured block we can immediately determine the phi arguments */
 	if (get_Block_matured(block)) {
 		int arity = get_irn_arity(block);
@@ -492,7 +501,6 @@ ir_node *new_rd_immBlock(dbg_info *dbgi, ir_graph *irg)
 	res = new_ir_node(dbgi, irg, NULL, op_Block, mode_BB, -1, NULL);
 
 	set_Block_matured(res, 0);
-	res->attr.block.is_dead     = 0;
 	res->attr.block.irg.irg     = irg;
 	res->attr.block.backedge    = NULL;
 	res->attr.block.in_cg       = NULL;
@@ -567,6 +575,7 @@ ir_node *get_r_value(ir_graph *irg, int pos, ir_mode *mode)
 {
 	assert(get_irg_phase_state(irg) == phase_building);
 	assert(pos >= 0);
+	inc_irg_visited(irg);
 
 	return get_r_value_internal(irg->current_block, pos + 1, mode);
 }
@@ -586,9 +595,8 @@ static ir_mode *guess_recursively(ir_node *block, int pos)
 	int      n_preds;
 	int      i;
 
-	if (irn_visited(block))
+	if (irn_visited_else_mark(block))
 		return NULL;
-	mark_irn_visited(block);
 
 	/* already have a defintion -> we can simply look at its mode */
 	value = block->attr.block.graph_arr[pos];
@@ -665,6 +673,7 @@ int find_value(ir_node *value)
 ir_node *get_r_store(ir_graph *irg)
 {
 	assert(get_irg_phase_state(irg) == phase_building);
+	inc_irg_visited(irg);
 	return get_r_value_internal(irg->current_block, 0, mode_M);
 }