X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fana%2Fircfscc.c;h=a5a53b70244c18baf94921cb64048e5be3b7aa70;hb=49bec3440763fcbac6bee60638cc8d699b12af11;hp=d4455417f333b4a67f3d583528d0e4e14fc714a8;hpb=ce6161a7e42a48f7422b7babcc64d8ace18e2687;p=libfirm

diff --git a/ir/ana/ircfscc.c b/ir/ana/ircfscc.c
index d4455417f..a5a53b702 100644
--- a/ir/ana/ircfscc.c
+++ b/ir/ana/ircfscc.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1995-2008 University of Karlsruhe.  All right reserved.
+ * Copyright (C) 1995-2011 University of Karlsruhe.  All right reserved.
  *
  * This file is part of libFirm.
  *
@@ -24,7 +24,6 @@
  *            [Trapp:99], Chapter 5.2.1.2.
  * @author    Goetz Lindenmaier
  * @date      7.2002
- * @version   $Id$
  */
 #include "config.h"
 
@@ -38,6 +37,7 @@
 #include "irgwalk.h"
 #include "irprog_t.h"
 #include "irdump.h"
+#include "ircons_t.h"
 
 #define NO_CFLOOPS_WITHOUT_HEAD 1
 
@@ -53,7 +53,7 @@ static int loop_node_cnt = 0;
 /** Counter to generate depth first numbering of visited nodes. */
 static int current_dfn = 1;
 
-static int max_loop_depth = 0;
+static unsigned max_loop_depth = 0;
 
 void link_to_reg_end(ir_node *n, void *env);
 
@@ -151,7 +151,7 @@ static inline int get_irn_dfn(ir_node *n)
 /** An IR-node stack */
 static ir_node **stack = NULL;
 /** The top (index) of the IR-node stack */
-static int tos = 0;
+static size_t    tos = 0;
 
 /**
  * Initializes the IR-node stack
@@ -178,7 +178,7 @@ static void finish_stack(void)
 static inline void push(ir_node *n)
 {
 	if (tos == ARR_LEN(stack)) {
-		int nlen = ARR_LEN(stack) * 2;
+		size_t nlen = ARR_LEN(stack) * 2;
 		ARR_RESIZE(ir_node *, stack, nlen);
 	}
 	stack[tos++] = n;
@@ -217,7 +217,7 @@ static inline void pop_scc_to_loop(ir_node *n)
    can't they have two loops as sons? Does it never get that far? ) */
 static void close_loop(ir_loop *l)
 {
-	int last = get_loop_n_elements(l) - 1;
+	size_t last = get_loop_n_elements(l) - 1;
 	loop_element lelement = get_loop_element(l, last);
 	ir_loop *last_son = lelement.son;
 
@@ -319,23 +319,6 @@ 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.
  *
@@ -350,21 +333,19 @@ static int is_head(ir_node *n, ir_node *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;
-			}
+	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;
 		}
 	}
 	return some_outof_loop & some_in_loop;
@@ -387,21 +368,19 @@ static int is_endless_head(ir_node *n, ir_node *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;
-			}
+	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;
 		}
 	}
 	return none_outof_loop && some_in_loop;
@@ -415,19 +394,17 @@ 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 +417,17 @@ 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;
@@ -467,9 +442,10 @@ static int largest_dfn_pred(ir_node *n)
 static ir_node *find_tail(ir_node *n)
 {
 	ir_node *m;
-	int i, res_index = -2;
+	int      res_index = -2;
+	size_t   i;
 
-	m = stack[tos-1];  /* tos = top of stack */
+	m = stack[tos - 1];  /* tos = top of stack */
 	if (is_head(m, n)) {
 		res_index = smallest_dfn_pred(m, 0);
 		if ((res_index == -2) &&  /* no smallest dfn pred found. */
@@ -478,16 +454,15 @@ static ir_node *find_tail(ir_node *n)
 	} else {
 		if (m == n)
 			return NULL;
-		for (i = tos-2; i >= 0; --i) {
-
-			m = stack[i];
+		for (i = tos - 1; i != 0;) {
+			m = stack[--i];
 			if (is_head(m, n)) {
 				res_index = smallest_dfn_pred(m, get_irn_dfn(m) + 1);
 				if (res_index == -2)  /* no smallest dfn pred found. */
 					res_index = largest_dfn_pred(m);
 
 				if ((m == n) && (res_index == -2)) {
-					i = -1;
+					i = (size_t)-1;
 				}
 				break;
 			}
@@ -496,15 +471,15 @@ static ir_node *find_tail(ir_node *n)
 			/* We should not walk past our selves on the stack:  The upcoming nodes
 			   are not in this loop. We assume a loop not reachable from Start. */
 			if (m == n) {
-				i = -1;
+				i = (size_t)-1;
 				break;
 			}
 		}
 
-		if (i < 0) {
+		if (i == (size_t)-1) {
 			/* A dead loop not reachable from Start. */
-			for (i = tos-2; i >= 0; --i) {
-				m = stack[i];
+			for (i = tos - 1; i != 0;) {
+				m = stack[--i];
 				if (is_endless_head(m, n)) {
 					res_index = smallest_dfn_pred (m, get_irn_dfn(m) + 1);
 					if (res_index == -2)  /* no smallest dfn pred found. */
@@ -519,7 +494,7 @@ 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 +514,7 @@ 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 +528,24 @@ 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));
 		}
 	}
 
@@ -642,7 +616,6 @@ static void cfscc(ir_node *n)
 	}
 }
 
-/* Constructs control flow backedge information for irg. */
 int construct_cf_backedges(ir_graph *irg)
 {
 	ir_graph *rem = current_ir_graph;
@@ -678,17 +651,15 @@ int construct_cf_backedges(ir_graph *irg)
 	assert(head_rem == current_loop);
 	mature_loops(current_loop, irg->obst);
 	set_irg_loop(irg, current_loop);
-	set_irg_loopinfo_state(irg, loopinfo_cf_consistent);
-	assert(get_irg_loop(irg)->kind == k_ir_loop);
+	add_irg_properties(irg, IR_GRAPH_PROPERTY_CONSISTENT_LOOPINFO);
 
 	current_ir_graph = rem;
 	return max_loop_depth;
 }
 
-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);
 }