X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;ds=sidebyside;f=ir%2Fana%2Fircfscc.c;h=5b89447e9f3ad2c78349eed7abffb91bba19225c;hb=b1ac8fe5c7b3b462f66a99e6c780be9826414b7d;hp=57a7ad46a7e806aebb1b1ce17550ebaeb1179127;hpb=1a3b7d363474ab544c13093a2f0b578718d37c7a;p=libfirm

diff --git a/ir/ana/ircfscc.c b/ir/ana/ircfscc.c
index 57a7ad46a..5b89447e9 100644
--- a/ir/ana/ircfscc.c
+++ b/ir/ana/ircfscc.c
@@ -1,20 +1,6 @@
 /*
- * Copyright (C) 1995-2011 University of Karlsruhe.  All right reserved.
- *
  * This file is part of libFirm.
- *
- * This file may be distributed and/or modified under the terms of the
- * GNU General Public License version 2 as published by the Free Software
- * Foundation and appearing in the file LICENSE.GPL included in the
- * packaging of this file.
- *
- * Licensees holding valid libFirm Professional Edition licenses may use
- * this file in accordance with the libFirm Commercial License.
- * Agreement provided with the Software.
- *
- * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
- * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE.
+ * Copyright (C) 2012 University of Karlsruhe.
  */
 
 /**
@@ -24,7 +10,6 @@
  *            [Trapp:99], Chapter 5.2.1.2.
  * @author    Goetz Lindenmaier
  * @date      7.2002
- * @version   $Id$
  */
 #include "config.h"
 
@@ -38,8 +23,7 @@
 #include "irgwalk.h"
 #include "irprog_t.h"
 #include "irdump.h"
-
-#define NO_CFLOOPS_WITHOUT_HEAD 1
+#include "ircons_t.h"
 
 /** The outermost graph the scc is computed for */
 static ir_graph *outermost_ir_graph;
@@ -53,14 +37,6 @@ static int loop_node_cnt = 0;
 /** Counter to generate depth first numbering of visited nodes. */
 static int current_dfn = 1;
 
-static unsigned max_loop_depth = 0;
-
-void link_to_reg_end(ir_node *n, void *env);
-
-/**********************************************************************/
-/* Node attributes                                                   **/
-/**********************************************************************/
-
 /**********************************************************************/
 /* Node attributes needed for the construction.                      **/
 /**********************************************************************/
@@ -268,9 +244,8 @@ static inline void pop_scc_unmark_visit(ir_node *n)
 static ir_loop *new_loop(void)
 {
 	ir_loop *father = current_loop;
-	ir_loop *son    = alloc_loop(father, outermost_ir_graph->obst);
+	ir_loop *son    = alloc_loop(father, get_irg_obstack(outermost_ir_graph));
 
-	if (son->depth > max_loop_depth) max_loop_depth = son->depth;
 	current_loop = son;
 	return father;
 }
@@ -319,23 +294,6 @@ static inline void finish_scc(void)
 	finish_stack();
 }
 
-/**
- * Condition for breaking the recursion: n is the block
- * that gets the initial control flow from the Start node.
- */
-static int is_outermost_StartBlock(ir_node *n)
-{
-	/* Test whether this is the outermost Start node.  If so
-	   recursion must end. */
-	assert(is_Block(n));
-	if (get_Block_n_cfgpreds(n) == 1  &&
-	    is_Start(skip_Proj(get_Block_cfgpred(n, 0))) &&
-	    get_Block_cfgpred_block(n, 0) == n) {
-		return 1;
-	}
-	return 0;
-}
-
 /** Returns non-zero if n is a loop header, i.e., it is a Block node
  *  and has predecessors within the cfloop and out of the cfloop.
  *
@@ -344,27 +302,22 @@ static int is_outermost_StartBlock(ir_node *n)
  */
 static int is_head(ir_node *n, ir_node *root)
 {
-	int i, arity;
 	int some_outof_loop = 0, some_in_loop = 0;
 	(void) root;
 
-	assert(is_Block(n));
-
-	if (!is_outermost_StartBlock(n)) {
-		arity = get_Block_n_cfgpreds(n);
-		for (i = 0; i < arity; i++) {
-			ir_node *pred = get_Block_cfgpred_block(n, i);
-			/* ignore Bad control flow: it cannot happen */
-			if (is_Bad(pred))
-				continue;
-			if (is_backedge(n, i))
-				continue;
-			if (!irn_is_in_stack(pred)) {
-				some_outof_loop = 1;
-			} else {
-				assert(get_irn_uplink(pred) >= get_irn_uplink(root));
-				some_in_loop = 1;
-			}
+	int const arity = get_Block_n_cfgpreds(n);
+	for (int i = 0; i < arity; i++) {
+		ir_node *pred = get_Block_cfgpred_block(n, i);
+		/* ignore Bad control flow: it cannot happen */
+		if (is_Bad(pred))
+			continue;
+		if (is_backedge(n, i))
+			continue;
+		if (!irn_is_in_stack(pred)) {
+			some_outof_loop = 1;
+		} else {
+			assert(get_irn_uplink(pred) >= get_irn_uplink(root));
+			some_in_loop = 1;
 		}
 	}
 	return some_outof_loop & some_in_loop;
@@ -381,27 +334,23 @@ static int is_head(ir_node *n, ir_node *root)
  */
 static int is_endless_head(ir_node *n, ir_node *root)
 {
-	int i, arity;
 	int none_outof_loop = 1, some_in_loop = 0;
 	(void) root;
 
-	assert(is_Block(n));
 	/* Test for legal loop header: Block, Phi, ... */
-	if (!is_outermost_StartBlock(n)) {
-		arity = get_Block_n_cfgpreds(n);
-		for (i = 0; i < arity; i++) {
-			ir_node *pred = get_Block_cfgpred_block(n, i);
-			/* ignore Bad control flow: it cannot happen */
-			if (is_Bad(pred))
-				continue;
-			if (is_backedge(n, i))
-				continue;
-			if (!irn_is_in_stack(pred)) {
-				none_outof_loop = 0;
-			} else {
-				assert(get_irn_uplink(pred) >= get_irn_uplink(root));
-				some_in_loop = 1;
-			}
+	int const arity = get_Block_n_cfgpreds(n);
+	for (int i = 0; i < arity; i++) {
+		ir_node *pred = get_Block_cfgpred_block(n, i);
+		/* ignore Bad control flow: it cannot happen */
+		if (is_Bad(pred))
+			continue;
+		if (is_backedge(n, i))
+			continue;
+		if (!irn_is_in_stack(pred)) {
+			none_outof_loop = 0;
+		} else {
+			assert(get_irn_uplink(pred) >= get_irn_uplink(root));
+			some_in_loop = 1;
 		}
 	}
 	return none_outof_loop && some_in_loop;
@@ -415,19 +364,17 @@ static int smallest_dfn_pred(ir_node *n, int limit)
 {
 	int i, index = -2, min = -1;
 
-	if (!is_outermost_StartBlock(n)) {
-		int arity = get_Block_n_cfgpreds(n);
-		for (i = 0; i < arity; i++) {
-			ir_node *pred = get_Block_cfgpred_block(n, i);
-			/* ignore Bad control flow: it cannot happen */
-			if (is_Bad(pred))
-				continue;
-			if (is_backedge(n, i) || !irn_is_in_stack(pred))
-				continue;
-			if (get_irn_dfn(pred) >= limit && (min == -1 || get_irn_dfn(pred) < min)) {
-				index = i;
-				min = get_irn_dfn(pred);
-			}
+	int arity = get_Block_n_cfgpreds(n);
+	for (i = 0; i < arity; i++) {
+		ir_node *pred = get_Block_cfgpred_block(n, i);
+		/* ignore Bad control flow: it cannot happen */
+		if (is_Bad(pred))
+			continue;
+		if (is_backedge(n, i) || !irn_is_in_stack(pred))
+			continue;
+		if (get_irn_dfn(pred) >= limit && (min == -1 || get_irn_dfn(pred) < min)) {
+			index = i;
+			min = get_irn_dfn(pred);
 		}
 	}
 	return index;
@@ -440,19 +387,17 @@ static int largest_dfn_pred(ir_node *n)
 {
 	int i, index = -2, max = -1;
 
-	if (!is_outermost_StartBlock(n)) {
-		int arity = get_Block_n_cfgpreds(n);
-		for (i = 0; i < arity; i++) {
-			ir_node *pred = get_Block_cfgpred_block(n, i);
-			/* ignore Bad control flow: it cannot happen */
-			if (is_Bad(pred))
-				continue;
-			if (is_backedge(n, i) || !irn_is_in_stack(pred))
-				continue;
-			if (get_irn_dfn(pred) > max) {
-				index = i;
-				max = get_irn_dfn(pred);
-			}
+	int arity = get_Block_n_cfgpreds(n);
+	for (i = 0; i < arity; i++) {
+		ir_node *pred = get_Block_cfgpred_block(n, i);
+		/* ignore Bad control flow: it cannot happen */
+		if (is_Bad(pred))
+			continue;
+		if (is_backedge(n, i) || !irn_is_in_stack(pred))
+			continue;
+		if (get_irn_dfn(pred) > max) {
+			index = i;
+			max = get_irn_dfn(pred);
 		}
 	}
 	return index;
@@ -519,7 +464,7 @@ static ir_node *find_tail(ir_node *n)
 	assert(res_index > -2);
 
 	set_backedge(m, res_index);
-	return is_outermost_StartBlock(n) ? NULL : get_Block_cfgpred_block(m, res_index);
+	return get_Block_cfgpred_block(m, res_index);
 }
 
 /**
@@ -539,6 +484,7 @@ inline static int is_outermost_loop(ir_loop *l)
  */
 static void cfscc(ir_node *n)
 {
+	int arity;
 	int i;
 
 	assert(is_Block(n));
@@ -552,26 +498,24 @@ static void cfscc(ir_node *n)
 	++current_dfn;
 	push(n);
 
-	if (!is_outermost_StartBlock(n)) {
-		int arity = get_Block_n_cfgpreds(n);
-
-		for (i = 0; i < arity; i++) {
-			ir_node *m;
-
-			if (is_backedge(n, i))
-				continue;
-			m = get_Block_cfgpred_block(n, i);
-			/* ignore Bad control flow: it cannot happen */
-			if (is_Bad(m))
-				continue;
-
-			cfscc(m);
-			if (irn_is_in_stack(m)) {
-				/* Uplink of m is smaller if n->m is a backedge.
-				   Propagate the uplink to mark the cfloop. */
-				if (get_irn_uplink(m) < get_irn_uplink(n))
-					set_irn_uplink(n, get_irn_uplink(m));
-			}
+	arity = get_Block_n_cfgpreds(n);
+
+	for (i = 0; i < arity; i++) {
+		ir_node *m;
+
+		if (is_backedge(n, i))
+			continue;
+		m = get_Block_cfgpred_block(n, i);
+		/* ignore Bad control flow: it cannot happen */
+		if (is_Bad(m))
+			continue;
+
+		cfscc(m);
+		if (irn_is_in_stack(m)) {
+			/* Uplink of m is smaller if n->m is a backedge.
+			   Propagate the uplink to mark the cfloop. */
+			if (get_irn_uplink(m) < get_irn_uplink(n))
+				set_irn_uplink(n, get_irn_uplink(m));
 		}
 	}
 
@@ -594,8 +538,6 @@ static void cfscc(ir_node *n)
 			   Next actions: Open a new cfloop on the cfloop tree and
 			   try to find inner cfloops */
 
-#if NO_CFLOOPS_WITHOUT_HEAD
-
 			/* This is an adaption of the algorithm from fiasco / optscc to
 			 * avoid cfloops without Block or Phi as first node.  This should
 			 * severely reduce the number of evaluations of nodes to detect
@@ -613,12 +555,6 @@ static void cfscc(ir_node *n)
 				close = 0;
 			}
 
-#else
-
-			ir_loop *l = new_loop();
-
-#endif
-
 			/* Remove the cfloop from the stack ... */
 			pop_scc_unmark_visit(n);
 
@@ -630,9 +566,7 @@ static void cfscc(ir_node *n)
 			cfscc(tail);
 
 			assert(irn_visited(n));
-#if NO_CFLOOPS_WITHOUT_HEAD
 			if (close)
-#endif
 				close_loop(l);
 		} else {
 			/* AS: No cfloop head was found, that is we have straight line code.
@@ -642,18 +576,13 @@ static void cfscc(ir_node *n)
 	}
 }
 
-/* Constructs control flow backedge information for irg. */
-int construct_cf_backedges(ir_graph *irg)
+void construct_cf_backedges(ir_graph *irg)
 {
-	ir_graph *rem = current_ir_graph;
 	ir_loop *head_rem;
 	ir_node *end = get_irg_end(irg);
 	struct obstack temp;
 	int i;
 
-	max_loop_depth = 0;
-
-	current_ir_graph   = irg;
 	outermost_ir_graph = irg;
 
 	obstack_init(&temp);
@@ -676,19 +605,14 @@ int construct_cf_backedges(ir_graph *irg)
 	obstack_free(&temp, NULL);
 
 	assert(head_rem == current_loop);
-	mature_loops(current_loop, irg->obst);
+	mature_loops(current_loop, get_irg_obstack(irg));
 	set_irg_loop(irg, current_loop);
-	set_irg_loopinfo_state(irg, loopinfo_cf_consistent);
-	assert(get_irg_loop(irg)->kind == k_ir_loop);
-
-	current_ir_graph = rem;
-	return max_loop_depth;
+	add_irg_properties(irg, IR_GRAPH_PROPERTY_CONSISTENT_LOOPINFO);
 }
 
-void assure_cf_loop(ir_graph *irg)
+void assure_loopinfo(ir_graph *irg)
 {
-	irg_loopinfo_state state = get_irg_loopinfo_state(irg);
-
-	if (state != loopinfo_cf_consistent)
-		construct_cf_backedges(irg);
+	if (irg_has_properties(irg, IR_GRAPH_PROPERTY_CONSISTENT_LOOPINFO))
+		return;
+	construct_cf_backedges(irg);
 }