/* Control flow graph analysis code for GNU compiler.
- Copyright (C) 1987-2012 Free Software Foundation, Inc.
+ Copyright (C) 1987-2016 Free Software Foundation, Inc.
This file is part of GCC.
#include "config.h"
#include "system.h"
#include "coretypes.h"
-#include "basic-block.h"
-#include "vec.h"
-#include "vecprim.h"
-#include "bitmap.h"
-#include "sbitmap.h"
+#include "backend.h"
+#include "cfghooks.h"
#include "timevar.h"
+#include "cfganal.h"
/* Store the data structures necessary for depth-first search. */
-struct depth_first_search_dsS {
+struct depth_first_search_ds {
/* stack for backtracking during the algorithm */
basic_block *stack;
/* record of basic blocks already seen by depth-first search */
sbitmap visited_blocks;
};
-typedef struct depth_first_search_dsS *depth_first_search_ds;
-static void flow_dfs_compute_reverse_init (depth_first_search_ds);
-static void flow_dfs_compute_reverse_add_bb (depth_first_search_ds,
+static void flow_dfs_compute_reverse_init (depth_first_search_ds *);
+static void flow_dfs_compute_reverse_add_bb (depth_first_search_ds *,
basic_block);
-static basic_block flow_dfs_compute_reverse_execute (depth_first_search_ds,
+static basic_block flow_dfs_compute_reverse_execute (depth_first_search_ds *,
basic_block);
-static void flow_dfs_compute_reverse_finish (depth_first_search_ds);
+static void flow_dfs_compute_reverse_finish (depth_first_search_ds *);
\f
/* Mark the back edges in DFS traversal.
Return nonzero if a loop (natural or otherwise) is present.
bool found = false;
/* Allocate the preorder and postorder number arrays. */
- pre = XCNEWVEC (int, last_basic_block);
- post = XCNEWVEC (int, last_basic_block);
+ pre = XCNEWVEC (int, last_basic_block_for_fn (cfun));
+ post = XCNEWVEC (int, last_basic_block_for_fn (cfun));
/* Allocate stack for back-tracking up CFG. */
- stack = XNEWVEC (edge_iterator, n_basic_blocks + 1);
+ stack = XNEWVEC (edge_iterator, n_basic_blocks_for_fn (cfun) + 1);
sp = 0;
/* Allocate bitmap to track nodes that have been visited. */
- visited = sbitmap_alloc (last_basic_block);
+ visited = sbitmap_alloc (last_basic_block_for_fn (cfun));
/* None of the nodes in the CFG have been visited yet. */
bitmap_clear (visited);
/* Push the first edge on to the stack. */
- stack[sp++] = ei_start (ENTRY_BLOCK_PTR->succs);
+ stack[sp++] = ei_start (ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs);
while (sp)
{
ei_edge (ei)->flags &= ~EDGE_DFS_BACK;
/* Check if the edge destination has been visited yet. */
- if (dest != EXIT_BLOCK_PTR && ! bitmap_bit_p (visited, dest->index))
+ if (dest != EXIT_BLOCK_PTR_FOR_FN (cfun) && ! bitmap_bit_p (visited,
+ dest->index))
{
/* Mark that we have visited the destination. */
bitmap_set_bit (visited, dest->index);
}
else
{
- if (dest != EXIT_BLOCK_PTR && src != ENTRY_BLOCK_PTR
+ if (dest != EXIT_BLOCK_PTR_FOR_FN (cfun)
+ && src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
&& pre[src->index] >= pre[dest->index]
&& post[dest->index] == 0)
ei_edge (ei)->flags |= EDGE_DFS_BACK, found = true;
- if (ei_one_before_end_p (ei) && src != ENTRY_BLOCK_PTR)
+ if (ei_one_before_end_p (ei)
+ && src != ENTRY_BLOCK_PTR_FOR_FN (cfun))
post[src->index] = postnum++;
if (!ei_one_before_end_p (ei))
edge_iterator ei;
basic_block *tos, *worklist, bb;
- tos = worklist = XNEWVEC (basic_block, n_basic_blocks);
+ tos = worklist = XNEWVEC (basic_block, n_basic_blocks_for_fn (cfun));
/* Clear all the reachability flags. */
- FOR_EACH_BB (bb)
+ FOR_EACH_BB_FN (bb, cfun)
bb->flags &= ~BB_REACHABLE;
/* Add our starting points to the worklist. Almost always there will
be only one. It isn't inconceivable that we might one day directly
support Fortran alternate entry points. */
- FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs)
+ FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs)
{
*tos++ = e->dest;
free (worklist);
}
+
+/* Verify that there are no unreachable blocks in the current function. */
+
+void
+verify_no_unreachable_blocks (void)
+{
+ find_unreachable_blocks ();
+
+ basic_block bb;
+ FOR_EACH_BB_FN (bb, cfun)
+ gcc_assert ((bb->flags & BB_REACHABLE) != 0);
+}
+
\f
/* Functions to access an edge list with a vector representation.
Enough data is kept such that given an index number, the
/* Determine the number of edges in the flow graph by counting successor
edges on each basic block. */
num_edges = 0;
- FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb)
+ FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR_FOR_FN (cfun),
+ EXIT_BLOCK_PTR_FOR_FN (cfun), next_bb)
{
num_edges += EDGE_COUNT (bb->succs);
}
num_edges = 0;
/* Follow successors of blocks, and register these edges. */
- FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb)
+ FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR_FOR_FN (cfun),
+ EXIT_BLOCK_PTR_FOR_FN (cfun), next_bb)
FOR_EACH_EDGE (e, ei, bb->succs)
elist->index_to_edge[num_edges++] = e;
int x;
fprintf (f, "Compressed edge list, %d BBs + entry & exit, and %d edges\n",
- n_basic_blocks, elist->num_edges);
+ n_basic_blocks_for_fn (cfun), elist->num_edges);
for (x = 0; x < elist->num_edges; x++)
{
fprintf (f, " %-4d - edge(", x);
- if (INDEX_EDGE_PRED_BB (elist, x) == ENTRY_BLOCK_PTR)
+ if (INDEX_EDGE_PRED_BB (elist, x) == ENTRY_BLOCK_PTR_FOR_FN (cfun))
fprintf (f, "entry,");
else
fprintf (f, "%d,", INDEX_EDGE_PRED_BB (elist, x)->index);
- if (INDEX_EDGE_SUCC_BB (elist, x) == EXIT_BLOCK_PTR)
+ if (INDEX_EDGE_SUCC_BB (elist, x) == EXIT_BLOCK_PTR_FOR_FN (cfun))
fprintf (f, "exit)\n");
else
fprintf (f, "%d)\n", INDEX_EDGE_SUCC_BB (elist, x)->index);
basic_block bb, p, s;
edge_iterator ei;
- FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb)
+ FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR_FOR_FN (cfun),
+ EXIT_BLOCK_PTR_FOR_FN (cfun), next_bb)
{
FOR_EACH_EDGE (e, ei, bb->succs)
{
/* We've verified that all the edges are in the list, now lets make sure
there are no spurious edges in the list. This is an expensive check! */
- FOR_BB_BETWEEN (p, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb)
- FOR_BB_BETWEEN (s, ENTRY_BLOCK_PTR->next_bb, NULL, next_bb)
+ FOR_BB_BETWEEN (p, ENTRY_BLOCK_PTR_FOR_FN (cfun),
+ EXIT_BLOCK_PTR_FOR_FN (cfun), next_bb)
+ FOR_BB_BETWEEN (s, ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb, NULL, next_bb)
{
int found_edge = 0;
}
}
+
+/* Functions to compute control dependences. */
+
+/* Indicate block BB is control dependent on an edge with index EDGE_INDEX. */
+void
+control_dependences::set_control_dependence_map_bit (basic_block bb,
+ int edge_index)
+{
+ if (bb == ENTRY_BLOCK_PTR_FOR_FN (cfun))
+ return;
+ gcc_assert (bb != EXIT_BLOCK_PTR_FOR_FN (cfun));
+ bitmap_set_bit (control_dependence_map[bb->index], edge_index);
+}
+
+/* Clear all control dependences for block BB. */
+void
+control_dependences::clear_control_dependence_bitmap (basic_block bb)
+{
+ bitmap_clear (control_dependence_map[bb->index]);
+}
+
+/* Find the immediate postdominator PDOM of the specified basic block BLOCK.
+ This function is necessary because some blocks have negative numbers. */
+
+static inline basic_block
+find_pdom (basic_block block)
+{
+ gcc_assert (block != ENTRY_BLOCK_PTR_FOR_FN (cfun));
+
+ if (block == EXIT_BLOCK_PTR_FOR_FN (cfun))
+ return EXIT_BLOCK_PTR_FOR_FN (cfun);
+ else
+ {
+ basic_block bb = get_immediate_dominator (CDI_POST_DOMINATORS, block);
+ if (! bb)
+ return EXIT_BLOCK_PTR_FOR_FN (cfun);
+ return bb;
+ }
+}
+
+/* Determine all blocks' control dependences on the given edge with edge_list
+ EL index EDGE_INDEX, ala Morgan, Section 3.6. */
+
+void
+control_dependences::find_control_dependence (int edge_index)
+{
+ basic_block current_block;
+ basic_block ending_block;
+
+ gcc_assert (INDEX_EDGE_PRED_BB (m_el, edge_index)
+ != EXIT_BLOCK_PTR_FOR_FN (cfun));
+
+ if (INDEX_EDGE_PRED_BB (m_el, edge_index) == ENTRY_BLOCK_PTR_FOR_FN (cfun))
+ ending_block = single_succ (ENTRY_BLOCK_PTR_FOR_FN (cfun));
+ else
+ ending_block = find_pdom (INDEX_EDGE_PRED_BB (m_el, edge_index));
+
+ for (current_block = INDEX_EDGE_SUCC_BB (m_el, edge_index);
+ current_block != ending_block
+ && current_block != EXIT_BLOCK_PTR_FOR_FN (cfun);
+ current_block = find_pdom (current_block))
+ {
+ edge e = INDEX_EDGE (m_el, edge_index);
+
+ /* For abnormal edges, we don't make current_block control
+ dependent because instructions that throw are always necessary
+ anyway. */
+ if (e->flags & EDGE_ABNORMAL)
+ continue;
+
+ set_control_dependence_map_bit (current_block, edge_index);
+ }
+}
+
+/* Record all blocks' control dependences on all edges in the edge
+ list EL, ala Morgan, Section 3.6. */
+
+control_dependences::control_dependences (struct edge_list *edges)
+ : m_el (edges)
+{
+ timevar_push (TV_CONTROL_DEPENDENCES);
+ control_dependence_map.create (last_basic_block_for_fn (cfun));
+ for (int i = 0; i < last_basic_block_for_fn (cfun); ++i)
+ control_dependence_map.quick_push (BITMAP_ALLOC (NULL));
+ for (int i = 0; i < NUM_EDGES (m_el); ++i)
+ find_control_dependence (i);
+ timevar_pop (TV_CONTROL_DEPENDENCES);
+}
+
+/* Free control dependences and the associated edge list. */
+
+control_dependences::~control_dependences ()
+{
+ for (unsigned i = 0; i < control_dependence_map.length (); ++i)
+ BITMAP_FREE (control_dependence_map[i]);
+ control_dependence_map.release ();
+ free_edge_list (m_el);
+}
+
+/* Returns the bitmap of edges the basic-block I is dependent on. */
+
+bitmap
+control_dependences::get_edges_dependent_on (int i)
+{
+ return control_dependence_map[i];
+}
+
+/* Returns the edge with index I from the edge list. */
+
+edge
+control_dependences::get_edge (int i)
+{
+ return INDEX_EDGE (m_el, i);
+}
+
+
/* Given PRED and SUCC blocks, return the edge which connects the blocks.
If no such edge exists, return NULL. */
{
basic_block bb;
- FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR->next_bb, NULL, next_bb)
+ FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb, NULL, next_bb)
remove_fake_predecessors (bb);
}
void
remove_fake_exit_edges (void)
{
- remove_fake_predecessors (EXIT_BLOCK_PTR);
+ remove_fake_predecessors (EXIT_BLOCK_PTR_FOR_FN (cfun));
}
{
basic_block bb;
- FOR_EACH_BB (bb)
+ FOR_EACH_BB_FN (bb, cfun)
if (EDGE_COUNT (bb->succs) == 0)
- make_single_succ_edge (bb, EXIT_BLOCK_PTR, EDGE_FAKE);
+ make_single_succ_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun), EDGE_FAKE);
}
/* This function adds a fake edge between any infinite loops to the
void
connect_infinite_loops_to_exit (void)
{
- basic_block unvisited_block = EXIT_BLOCK_PTR;
+ basic_block unvisited_block = EXIT_BLOCK_PTR_FOR_FN (cfun);
basic_block deadend_block;
- struct depth_first_search_dsS dfs_ds;
+ depth_first_search_ds dfs_ds;
/* Perform depth-first search in the reverse graph to find nodes
reachable from the exit block. */
flow_dfs_compute_reverse_init (&dfs_ds);
- flow_dfs_compute_reverse_add_bb (&dfs_ds, EXIT_BLOCK_PTR);
+ flow_dfs_compute_reverse_add_bb (&dfs_ds, EXIT_BLOCK_PTR_FOR_FN (cfun));
/* Repeatedly add fake edges, updating the unreachable nodes. */
while (1)
break;
deadend_block = dfs_find_deadend (unvisited_block);
- make_edge (deadend_block, EXIT_BLOCK_PTR, EDGE_FAKE);
+ make_edge (deadend_block, EXIT_BLOCK_PTR_FOR_FN (cfun), EDGE_FAKE);
flow_dfs_compute_reverse_add_bb (&dfs_ds, deadend_block);
}
post_order[post_order_num++] = EXIT_BLOCK;
/* Allocate stack for back-tracking up CFG. */
- stack = XNEWVEC (edge_iterator, n_basic_blocks + 1);
+ stack = XNEWVEC (edge_iterator, n_basic_blocks_for_fn (cfun) + 1);
sp = 0;
/* Allocate bitmap to track nodes that have been visited. */
- visited = sbitmap_alloc (last_basic_block);
+ visited = sbitmap_alloc (last_basic_block_for_fn (cfun));
/* None of the nodes in the CFG have been visited yet. */
bitmap_clear (visited);
/* Push the first edge on to the stack. */
- stack[sp++] = ei_start (ENTRY_BLOCK_PTR->succs);
+ stack[sp++] = ei_start (ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs);
while (sp)
{
dest = ei_edge (ei)->dest;
/* Check if the edge destination has been visited yet. */
- if (dest != EXIT_BLOCK_PTR && ! bitmap_bit_p (visited, dest->index))
+ if (dest != EXIT_BLOCK_PTR_FOR_FN (cfun)
+ && ! bitmap_bit_p (visited, dest->index))
{
/* Mark that we have visited the destination. */
bitmap_set_bit (visited, dest->index);
}
else
{
- if (ei_one_before_end_p (ei) && src != ENTRY_BLOCK_PTR)
+ if (ei_one_before_end_p (ei)
+ && src != ENTRY_BLOCK_PTR_FOR_FN (cfun))
post_order[post_order_num++] = src->index;
if (!ei_one_before_end_p (ei))
/* Delete the unreachable blocks if some were found and we are
supposed to do it. */
- if (delete_unreachable && (count != n_basic_blocks))
+ if (delete_unreachable && (count != n_basic_blocks_for_fn (cfun)))
{
basic_block b;
basic_block next_bb;
- for (b = ENTRY_BLOCK_PTR->next_bb; b != EXIT_BLOCK_PTR; b = next_bb)
+ for (b = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; b
+ != EXIT_BLOCK_PTR_FOR_FN (cfun); b = next_bb)
{
next_bb = b->next_bb;
(from successors to predecessors).
This ordering can be used for forward dataflow problems among others.
+ Optionally if START_POINTS is specified, start from exit block and all
+ basic blocks in START_POINTS. This is used by CD-DCE.
+
This function assumes that all blocks in the CFG are reachable
from the ENTRY (but not necessarily from EXIT).
and do another inverted traversal from that block. */
int
-inverted_post_order_compute (int *post_order)
+inverted_post_order_compute (int *post_order,
+ sbitmap *start_points)
{
basic_block bb;
edge_iterator *stack;
int post_order_num = 0;
sbitmap visited;
+ if (flag_checking)
+ verify_no_unreachable_blocks ();
+
/* Allocate stack for back-tracking up CFG. */
- stack = XNEWVEC (edge_iterator, n_basic_blocks + 1);
+ stack = XNEWVEC (edge_iterator, n_basic_blocks_for_fn (cfun) + 1);
sp = 0;
/* Allocate bitmap to track nodes that have been visited. */
- visited = sbitmap_alloc (last_basic_block);
+ visited = sbitmap_alloc (last_basic_block_for_fn (cfun));
/* None of the nodes in the CFG have been visited yet. */
bitmap_clear (visited);
+ if (start_points)
+ {
+ FOR_ALL_BB_FN (bb, cfun)
+ if (bitmap_bit_p (*start_points, bb->index)
+ && EDGE_COUNT (bb->preds) > 0)
+ {
+ stack[sp++] = ei_start (bb->preds);
+ bitmap_set_bit (visited, bb->index);
+ }
+ if (EDGE_COUNT (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds))
+ {
+ stack[sp++] = ei_start (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds);
+ bitmap_set_bit (visited, EXIT_BLOCK_PTR_FOR_FN (cfun)->index);
+ }
+ }
+ else
/* Put all blocks that have no successor into the initial work list. */
- FOR_ALL_BB (bb)
+ FOR_ALL_BB_FN (bb, cfun)
if (EDGE_COUNT (bb->succs) == 0)
{
/* Push the initial edge on to the stack. */
}
else
{
- if (bb != EXIT_BLOCK_PTR && ei_one_before_end_p (ei))
+ if (bb != EXIT_BLOCK_PTR_FOR_FN (cfun)
+ && ei_one_before_end_p (ei))
post_order[post_order_num++] = bb->index;
if (!ei_one_before_end_p (ei))
/* Detect any infinite loop and activate the kludge.
Note that this doesn't check EXIT_BLOCK itself
since EXIT_BLOCK is always added after the outer do-while loop. */
- FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb)
+ FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR_FOR_FN (cfun),
+ EXIT_BLOCK_PTR_FOR_FN (cfun), next_bb)
if (!bitmap_bit_p (visited, bb->index))
{
has_unvisited_bb = true;
{
/* No blocks are reachable from EXIT at all.
Find a dead-end from the ENTRY, and restart the iteration. */
- basic_block be = dfs_find_deadend (ENTRY_BLOCK_PTR);
+ basic_block be = dfs_find_deadend (ENTRY_BLOCK_PTR_FOR_FN (cfun));
gcc_assert (be != NULL);
bitmap_set_bit (visited, be->index);
stack[sp++] = ei_start (be->preds);
return post_order_num;
}
-/* Compute the depth first search order and store in the array
- PRE_ORDER if nonzero, marking the nodes visited in VISITED. If
- REV_POST_ORDER is nonzero, return the reverse completion number for each
- node. Returns the number of nodes visited. A depth first search
- tries to get as far away from the starting point as quickly as
- possible.
+/* Compute the depth first search order of FN and store in the array
+ PRE_ORDER if nonzero. If REV_POST_ORDER is nonzero, return the
+ reverse completion number for each node. Returns the number of nodes
+ visited. A depth first search tries to get as far away from the starting
+ point as quickly as possible.
- pre_order is a really a preorder numbering of the graph.
- rev_post_order is really a reverse postorder numbering of the graph.
- */
+ In case the function has unreachable blocks the number of nodes
+ visited does not include them.
+
+ pre_order is a really a preorder numbering of the graph.
+ rev_post_order is really a reverse postorder numbering of the graph. */
int
-pre_and_rev_post_order_compute (int *pre_order, int *rev_post_order,
- bool include_entry_exit)
+pre_and_rev_post_order_compute_fn (struct function *fn,
+ int *pre_order, int *rev_post_order,
+ bool include_entry_exit)
{
edge_iterator *stack;
int sp;
int pre_order_num = 0;
- int rev_post_order_num = n_basic_blocks - 1;
+ int rev_post_order_num = n_basic_blocks_for_fn (cfun) - 1;
sbitmap visited;
/* Allocate stack for back-tracking up CFG. */
- stack = XNEWVEC (edge_iterator, n_basic_blocks + 1);
+ stack = XNEWVEC (edge_iterator, n_basic_blocks_for_fn (cfun) + 1);
sp = 0;
if (include_entry_exit)
pre_order[pre_order_num] = ENTRY_BLOCK;
pre_order_num++;
if (rev_post_order)
- rev_post_order[rev_post_order_num--] = ENTRY_BLOCK;
+ rev_post_order[rev_post_order_num--] = EXIT_BLOCK;
}
else
rev_post_order_num -= NUM_FIXED_BLOCKS;
/* Allocate bitmap to track nodes that have been visited. */
- visited = sbitmap_alloc (last_basic_block);
+ visited = sbitmap_alloc (last_basic_block_for_fn (cfun));
/* None of the nodes in the CFG have been visited yet. */
bitmap_clear (visited);
/* Push the first edge on to the stack. */
- stack[sp++] = ei_start (ENTRY_BLOCK_PTR->succs);
+ stack[sp++] = ei_start (ENTRY_BLOCK_PTR_FOR_FN (fn)->succs);
while (sp)
{
dest = ei_edge (ei)->dest;
/* Check if the edge destination has been visited yet. */
- if (dest != EXIT_BLOCK_PTR && ! bitmap_bit_p (visited, dest->index))
+ if (dest != EXIT_BLOCK_PTR_FOR_FN (fn)
+ && ! bitmap_bit_p (visited, dest->index))
{
/* Mark that we have visited the destination. */
bitmap_set_bit (visited, dest->index);
}
else
{
- if (ei_one_before_end_p (ei) && src != ENTRY_BLOCK_PTR
+ if (ei_one_before_end_p (ei)
+ && src != ENTRY_BLOCK_PTR_FOR_FN (fn)
&& rev_post_order)
/* There are no more successors for the SRC node
so assign its reverse completion number. */
pre_order[pre_order_num] = EXIT_BLOCK;
pre_order_num++;
if (rev_post_order)
- rev_post_order[rev_post_order_num--] = EXIT_BLOCK;
- /* The number of nodes visited should be the number of blocks. */
- gcc_assert (pre_order_num == n_basic_blocks);
+ rev_post_order[rev_post_order_num--] = ENTRY_BLOCK;
}
+
+ return pre_order_num;
+}
+
+/* Like pre_and_rev_post_order_compute_fn but operating on the
+ current function and asserting that all nodes were visited. */
+
+int
+pre_and_rev_post_order_compute (int *pre_order, int *rev_post_order,
+ bool include_entry_exit)
+{
+ int pre_order_num
+ = pre_and_rev_post_order_compute_fn (cfun, pre_order, rev_post_order,
+ include_entry_exit);
+ if (include_entry_exit)
+ /* The number of nodes visited should be the number of blocks. */
+ gcc_assert (pre_order_num == n_basic_blocks_for_fn (cfun));
else
/* The number of nodes visited should be the number of blocks minus
the entry and exit blocks which are not visited here. */
- gcc_assert (pre_order_num == n_basic_blocks - NUM_FIXED_BLOCKS);
+ gcc_assert (pre_order_num
+ == (n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS));
return pre_order_num;
}
element on the stack. */
static void
-flow_dfs_compute_reverse_init (depth_first_search_ds data)
+flow_dfs_compute_reverse_init (depth_first_search_ds *data)
{
/* Allocate stack for back-tracking up CFG. */
- data->stack = XNEWVEC (basic_block, n_basic_blocks);
+ data->stack = XNEWVEC (basic_block, n_basic_blocks_for_fn (cfun));
data->sp = 0;
/* Allocate bitmap to track nodes that have been visited. */
- data->visited_blocks = sbitmap_alloc (last_basic_block);
+ data->visited_blocks = sbitmap_alloc (last_basic_block_for_fn (cfun));
/* None of the nodes in the CFG have been visited yet. */
bitmap_clear (data->visited_blocks);
block. */
static void
-flow_dfs_compute_reverse_add_bb (depth_first_search_ds data, basic_block bb)
+flow_dfs_compute_reverse_add_bb (depth_first_search_ds *data, basic_block bb)
{
data->stack[data->sp++] = bb;
bitmap_set_bit (data->visited_blocks, bb->index);
available. */
static basic_block
-flow_dfs_compute_reverse_execute (depth_first_search_ds data,
+flow_dfs_compute_reverse_execute (depth_first_search_ds *data,
basic_block last_unvisited)
{
basic_block bb;
reverse graph. */
static void
-flow_dfs_compute_reverse_finish (depth_first_search_ds data)
+flow_dfs_compute_reverse_finish (depth_first_search_ds *data)
{
free (data->stack);
sbitmap_free (data->visited_blocks);
#define VISITED_P(BB) (bitmap_bit_p (visited, (BB)->index))
/* Resize the VISITED sbitmap if necessary. */
- size = last_basic_block;
+ size = last_basic_block_for_fn (cfun);
if (size < 10)
size = 10;
edge p;
edge_iterator ei;
basic_block b;
- FOR_EACH_BB (b)
+ FOR_EACH_BB_FN (b, cfun)
{
if (EDGE_COUNT (b->preds) >= 2)
{
{
basic_block runner = p->src;
basic_block domsb;
- if (runner == ENTRY_BLOCK_PTR)
+ if (runner == ENTRY_BLOCK_PTR_FOR_FN (cfun))
continue;
domsb = get_immediate_dominator (CDI_DOMINATORS, b);
{
bitmap_iterator bi;
unsigned bb_index, i;
- VEC(int,heap) *work_stack;
bitmap phi_insertion_points;
- work_stack = VEC_alloc (int, heap, n_basic_blocks);
+ /* Each block can appear at most twice on the work-stack. */
+ auto_vec<int> work_stack (2 * n_basic_blocks_for_fn (cfun));
phi_insertion_points = BITMAP_ALLOC (NULL);
/* Seed the work list with all the blocks in DEF_BLOCKS. We use
- VEC_quick_push here for speed. This is safe because we know that
+ vec::quick_push here for speed. This is safe because we know that
the number of definition blocks is no greater than the number of
basic blocks, which is the initial capacity of WORK_STACK. */
EXECUTE_IF_SET_IN_BITMAP (def_blocks, 0, bb_index, bi)
- VEC_quick_push (int, work_stack, bb_index);
+ work_stack.quick_push (bb_index);
/* Pop a block off the worklist, add every block that appears in
the original block's DF that we have not already processed to
the worklist. Iterate until the worklist is empty. Blocks
which are added to the worklist are potential sites for
PHI nodes. */
- while (VEC_length (int, work_stack) > 0)
+ while (work_stack.length () > 0)
{
- bb_index = VEC_pop (int, work_stack);
+ bb_index = work_stack.pop ();
/* Since the registration of NEW -> OLD name mappings is done
separately from the call to update_ssa, when updating the SSA
form, the basic blocks where new and/or old names are defined
may have disappeared by CFG cleanup calls. In this case,
we may pull a non-existing block from the work stack. */
- gcc_assert (bb_index < (unsigned) last_basic_block);
+ gcc_checking_assert (bb_index
+ < (unsigned) last_basic_block_for_fn (cfun));
EXECUTE_IF_AND_COMPL_IN_BITMAP (&dfs[bb_index], phi_insertion_points,
0, i, bi)
{
- /* Use a safe push because if there is a definition of VAR
- in every basic block, then WORK_STACK may eventually have
- more than N_BASIC_BLOCK entries. */
- VEC_safe_push (int, heap, work_stack, i);
+ work_stack.quick_push (i);
bitmap_set_bit (phi_insertion_points, i);
}
}
- VEC_free (int, heap, work_stack);
-
return phi_insertion_points;
}
for (e = NULL, ix = 0; ix < EDGE_COUNT (b->succs); ix++)
{
e = EDGE_SUCC (b, ix);
- if (e->dest == EXIT_BLOCK_PTR)
+ if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
continue;
bitmap_copy (dst, src[e->dest->index]);
SBITMAP_ELT_TYPE *p, *r;
e = EDGE_SUCC (b, ix);
- if (e->dest == EXIT_BLOCK_PTR)
+ if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
continue;
p = src[e->dest->index]->elms;
for (e = NULL, ix = 0; ix < EDGE_COUNT (b->preds); ix++)
{
e = EDGE_PRED (b, ix);
- if (e->src == ENTRY_BLOCK_PTR)
+ if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun))
continue;
bitmap_copy (dst, src[e->src->index]);
SBITMAP_ELT_TYPE *p, *r;
e = EDGE_PRED (b, ix);
- if (e->src == ENTRY_BLOCK_PTR)
+ if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun))
continue;
p = src[e->src->index]->elms;
for (ix = 0; ix < EDGE_COUNT (b->succs); ix++)
{
e = EDGE_SUCC (b, ix);
- if (e->dest == EXIT_BLOCK_PTR)
+ if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
continue;
bitmap_copy (dst, src[e->dest->index]);
SBITMAP_ELT_TYPE *p, *r;
e = EDGE_SUCC (b, ix);
- if (e->dest == EXIT_BLOCK_PTR)
+ if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
continue;
p = src[e->dest->index]->elms;
for (ix = 0; ix < EDGE_COUNT (b->preds); ix++)
{
e = EDGE_PRED (b, ix);
- if (e->src== ENTRY_BLOCK_PTR)
+ if (e->src== ENTRY_BLOCK_PTR_FOR_FN (cfun))
continue;
bitmap_copy (dst, src[e->src->index]);
SBITMAP_ELT_TYPE *p, *r;
e = EDGE_PRED (b, ix);
- if (e->src == ENTRY_BLOCK_PTR)
+ if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun))
continue;
p = src[e->src->index]->elms;
*r++ |= *p++;
}
}
+
+/* Returns the list of basic blocks in the function in an order that guarantees
+ that if a block X has just a single predecessor Y, then Y is after X in the
+ ordering. */
+
+basic_block *
+single_pred_before_succ_order (void)
+{
+ basic_block x, y;
+ basic_block *order = XNEWVEC (basic_block, n_basic_blocks_for_fn (cfun));
+ unsigned n = n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS;
+ unsigned np, i;
+ sbitmap visited = sbitmap_alloc (last_basic_block_for_fn (cfun));
+
+#define MARK_VISITED(BB) (bitmap_set_bit (visited, (BB)->index))
+#define VISITED_P(BB) (bitmap_bit_p (visited, (BB)->index))
+
+ bitmap_clear (visited);
+
+ MARK_VISITED (ENTRY_BLOCK_PTR_FOR_FN (cfun));
+ FOR_EACH_BB_FN (x, cfun)
+ {
+ if (VISITED_P (x))
+ continue;
+
+ /* Walk the predecessors of x as long as they have precisely one
+ predecessor and add them to the list, so that they get stored
+ after x. */
+ for (y = x, np = 1;
+ single_pred_p (y) && !VISITED_P (single_pred (y));
+ y = single_pred (y))
+ np++;
+ for (y = x, i = n - np;
+ single_pred_p (y) && !VISITED_P (single_pred (y));
+ y = single_pred (y), i++)
+ {
+ order[i] = y;
+ MARK_VISITED (y);
+ }
+ order[i] = y;
+ MARK_VISITED (y);
+
+ gcc_assert (i == n - 1);
+ n -= np;
+ }
+
+ sbitmap_free (visited);
+ gcc_assert (n == 0);
+ return order;
+
+#undef MARK_VISITED
+#undef VISITED_P
+}
projects / gcc.git / blobdiff