-/* Generic partial redundancy elimination with lazy code motion
- support.
- Copyright (C) 1998 Free Software Foundation, Inc.
+/* Generic partial redundancy elimination with lazy code motion support.
+ Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008
+ Free Software Foundation, Inc.
-This file is part of GNU CC.
+This file is part of GCC.
-GNU CC is free software; you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2, or (at your option)
-any later version.
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
-GNU CC is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-GNU General Public License for more details.
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+for more details.
You should have received a copy of the GNU General Public License
-along with GNU CC; see the file COPYING. If not, write to
-the Free Software Foundation, 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, USA. */
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
/* These routines are meant to be used by various optimization
- passes which can be modeled as lazy code motion problems.
+ passes which can be modeled as lazy code motion problems.
Including, but not limited to:
* Traditional partial redundancy elimination.
#include "config.h"
#include "system.h"
-
+#include "coretypes.h"
+#include "tm.h"
#include "rtl.h"
#include "regs.h"
#include "hard-reg-set.h"
#include "flags.h"
-#include "real.h"
#include "insn-config.h"
#include "recog.h"
#include "basic-block.h"
+#include "output.h"
+#include "tm_p.h"
+#include "function.h"
+#include "sbitmap.h"
+
+/* We want target macros for the mode switching code to be able to refer
+ to instruction attribute values. */
+#include "insn-attr.h"
/* Edge based LCM routines. */
-static void compute_antinout_edge PROTO ((sbitmap *, sbitmap *,
- sbitmap *, sbitmap *));
-static void compute_earliest PROTO((struct edge_list *, int, sbitmap *,
- sbitmap *, sbitmap *, sbitmap *,
- sbitmap *));
-static void compute_laterin PROTO((struct edge_list *, int, sbitmap *,
- sbitmap *, sbitmap *, sbitmap *));
-static void compute_insert_delete PROTO ((struct edge_list *edge_list,
- sbitmap *, sbitmap *, sbitmap *,
- sbitmap *, sbitmap *));
+static void compute_antinout_edge (sbitmap *, sbitmap *, sbitmap *, sbitmap *);
+static void compute_earliest (struct edge_list *, int, sbitmap *, sbitmap *,
+ sbitmap *, sbitmap *, sbitmap *);
+static void compute_laterin (struct edge_list *, sbitmap *, sbitmap *,
+ sbitmap *, sbitmap *);
+static void compute_insert_delete (struct edge_list *edge_list, sbitmap *,
+ sbitmap *, sbitmap *, sbitmap *, sbitmap *);
/* Edge based LCM routines on a reverse flowgraph. */
-static void compute_farthest PROTO ((struct edge_list *, int, sbitmap *,
- sbitmap *, sbitmap*, sbitmap *,
- sbitmap *));
-static void compute_nearerout PROTO((struct edge_list *, int, sbitmap *,
- sbitmap *, sbitmap *, sbitmap *));
-static void compute_rev_insert_delete PROTO ((struct edge_list *edge_list,
- sbitmap *, sbitmap *, sbitmap *,
- sbitmap *, sbitmap *));
-
+static void compute_farthest (struct edge_list *, int, sbitmap *, sbitmap *,
+ sbitmap*, sbitmap *, sbitmap *);
+static void compute_nearerout (struct edge_list *, sbitmap *, sbitmap *,
+ sbitmap *, sbitmap *);
+static void compute_rev_insert_delete (struct edge_list *edge_list, sbitmap *,
+ sbitmap *, sbitmap *, sbitmap *,
+ sbitmap *);
\f
/* Edge based lcm routines. */
-/* Compute expression anticipatability at entrance and exit of each block.
- This is done based on the flow graph, and not on the pred-succ lists.
+/* Compute expression anticipatability at entrance and exit of each block.
+ This is done based on the flow graph, and not on the pred-succ lists.
Other than that, its pretty much identical to compute_antinout. */
static void
-compute_antinout_edge (antloc, transp, antin, antout)
- sbitmap *antloc;
- sbitmap *transp;
- sbitmap *antin;
- sbitmap *antout;
+compute_antinout_edge (sbitmap *antloc, sbitmap *transp, sbitmap *antin,
+ sbitmap *antout)
{
- int i, changed, passes;
- sbitmap old_changed, new_changed;
+ basic_block bb;
edge e;
+ basic_block *worklist, *qin, *qout, *qend;
+ unsigned int qlen;
+ edge_iterator ei;
+
+ /* Allocate a worklist array/queue. Entries are only added to the
+ list if they were not already on the list. So the size is
+ bounded by the number of basic blocks. */
+ qin = qout = worklist = XNEWVEC (basic_block, n_basic_blocks);
+
+ /* We want a maximal solution, so make an optimistic initialization of
+ ANTIN. */
+ sbitmap_vector_ones (antin, last_basic_block);
+
+ /* Put every block on the worklist; this is necessary because of the
+ optimistic initialization of ANTIN above. */
+ FOR_EACH_BB_REVERSE (bb)
+ {
+ *qin++ = bb;
+ bb->aux = bb;
+ }
- sbitmap_vector_zero (antout, n_basic_blocks);
- sbitmap_vector_ones (antin, n_basic_blocks);
+ qin = worklist;
+ qend = &worklist[n_basic_blocks - NUM_FIXED_BLOCKS];
+ qlen = n_basic_blocks - NUM_FIXED_BLOCKS;
- old_changed = sbitmap_alloc (n_basic_blocks);
- new_changed = sbitmap_alloc (n_basic_blocks);
- sbitmap_ones (old_changed);
+ /* Mark blocks which are predecessors of the exit block so that we
+ can easily identify them below. */
+ FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
+ e->src->aux = EXIT_BLOCK_PTR;
- passes = 0;
- changed = 1;
- while (changed)
+ /* Iterate until the worklist is empty. */
+ while (qlen)
{
- changed = 0;
- sbitmap_zero (new_changed);
-
- /* We scan the blocks in the reverse order to speed up
- the convergence. */
- for (i = n_basic_blocks - 1; i >= 0; i--)
+ /* Take the first entry off the worklist. */
+ bb = *qout++;
+ qlen--;
+
+ if (qout >= qend)
+ qout = worklist;
+
+ if (bb->aux == EXIT_BLOCK_PTR)
+ /* Do not clear the aux field for blocks which are predecessors of
+ the EXIT block. That way we never add then to the worklist
+ again. */
+ sbitmap_zero (antout[bb->index]);
+ else
{
- basic_block bb = BASIC_BLOCK (i);
- /* If none of the successors of this block have changed,
- then this block is not going to change. */
- for (e = bb->succ ; e; e = e->succ_next)
- {
- if (e->dest == EXIT_BLOCK_PTR)
- break;
-
- if (TEST_BIT (old_changed, e->dest->index)
- || TEST_BIT (new_changed, e->dest->index))
- break;
- }
-
- if (!e)
- continue;
-
- /* If an Exit blocks is the ONLY successor, its has a zero ANTIN,
- which is the opposite of the default definition for an
- intersection of succs definition. */
- if (e->dest == EXIT_BLOCK_PTR && e->succ_next == NULL
- && e->src->succ == e)
- sbitmap_zero (antout[bb->index]);
- else
- {
- sbitmap_intersection_of_succs (antout[bb->index],
- antin,
- bb->index);
- }
+ /* Clear the aux field of this block so that it can be added to
+ the worklist again if necessary. */
+ bb->aux = NULL;
+ sbitmap_intersection_of_succs (antout[bb->index], antin, bb->index);
+ }
- if (sbitmap_a_or_b_and_c (antin[bb->index], antloc[bb->index],
- transp[bb->index], antout[bb->index]))
+ if (sbitmap_a_or_b_and_c_cg (antin[bb->index], antloc[bb->index],
+ transp[bb->index], antout[bb->index]))
+ /* If the in state of this block changed, then we need
+ to add the predecessors of this block to the worklist
+ if they are not already on the worklist. */
+ FOR_EACH_EDGE (e, ei, bb->preds)
+ if (!e->src->aux && e->src != ENTRY_BLOCK_PTR)
{
- changed = 1;
- SET_BIT (new_changed, bb->index);
+ *qin++ = e->src;
+ e->src->aux = e;
+ qlen++;
+ if (qin >= qend)
+ qin = worklist;
}
- }
- sbitmap_copy (old_changed, new_changed);
- passes++;
}
- free (old_changed);
- free (new_changed);
+ clear_aux_for_edges ();
+ clear_aux_for_blocks ();
+ free (worklist);
}
/* Compute the earliest vector for edge based lcm. */
+
static void
-compute_earliest (edge_list, n_exprs, antin, antout, avout, kill, earliest)
- struct edge_list *edge_list;
- int n_exprs;
- sbitmap *antin, *antout, *avout, *kill, *earliest;
+compute_earliest (struct edge_list *edge_list, int n_exprs, sbitmap *antin,
+ sbitmap *antout, sbitmap *avout, sbitmap *kill,
+ sbitmap *earliest)
{
sbitmap difference, temp_bitmap;
- int x, num_edges;
+ int x, num_edges;
basic_block pred, succ;
num_edges = NUM_EDGES (edge_list);
if (pred == ENTRY_BLOCK_PTR)
sbitmap_copy (earliest[x], antin[succ->index]);
else
- {
+ {
if (succ == EXIT_BLOCK_PTR)
- {
- sbitmap_zero (earliest[x]);
- }
+ sbitmap_zero (earliest[x]);
else
{
- sbitmap_difference (difference, antin[succ->index],
- avout[pred->index]);
+ sbitmap_difference (difference, antin[succ->index],
+ avout[pred->index]);
sbitmap_not (temp_bitmap, antout[pred->index]);
- sbitmap_a_and_b_or_c (earliest[x], difference, kill[pred->index],
- temp_bitmap);
+ sbitmap_a_and_b_or_c (earliest[x], difference,
+ kill[pred->index], temp_bitmap);
}
}
}
- free (temp_bitmap);
- free (difference);
+
+ sbitmap_free (temp_bitmap);
+ sbitmap_free (difference);
}
-/* Compute later and laterin vectors for edge based lcm. */
+/* later(p,s) is dependent on the calculation of laterin(p).
+ laterin(p) is dependent on the calculation of later(p2,p).
+
+ laterin(ENTRY) is defined as all 0's
+ later(ENTRY, succs(ENTRY)) are defined using laterin(ENTRY)
+ laterin(succs(ENTRY)) is defined by later(ENTRY, succs(ENTRY)).
+
+ If we progress in this manner, starting with all basic blocks
+ in the work list, anytime we change later(bb), we need to add
+ succs(bb) to the worklist if they are not already on the worklist.
+
+ Boundary conditions:
+
+ We prime the worklist all the normal basic blocks. The ENTRY block can
+ never be added to the worklist since it is never the successor of any
+ block. We explicitly prevent the EXIT block from being added to the
+ worklist.
+
+ We optimistically initialize LATER. That is the only time this routine
+ will compute LATER for an edge out of the entry block since the entry
+ block is never on the worklist. Thus, LATERIN is neither used nor
+ computed for the ENTRY block.
+
+ Since the EXIT block is never added to the worklist, we will neither
+ use nor compute LATERIN for the exit block. Edges which reach the
+ EXIT block are handled in the normal fashion inside the loop. However,
+ the insertion/deletion computation needs LATERIN(EXIT), so we have
+ to compute it. */
+
static void
-compute_laterin (edge_list, n_exprs,
- earliest, antloc, later, laterin)
- struct edge_list *edge_list;
- int n_exprs;
- sbitmap *earliest, *antloc, *later, *laterin;
+compute_laterin (struct edge_list *edge_list, sbitmap *earliest,
+ sbitmap *antloc, sbitmap *later, sbitmap *laterin)
{
- sbitmap difference, temp_bitmap;
- int x, num_edges;
- basic_block pred, succ;
- int done = 0;
+ int num_edges, i;
+ edge e;
+ basic_block *worklist, *qin, *qout, *qend, bb;
+ unsigned int qlen;
+ edge_iterator ei;
num_edges = NUM_EDGES (edge_list);
- /* Laterin has an extra block allocated for the exit block. */
- sbitmap_vector_ones (laterin, n_basic_blocks + 1);
- sbitmap_vector_zero (later, num_edges);
-
- /* Initialize laterin to the intersection of EARLIEST for all edges
- from predecessors to this block. */
-
- for (x = 0; x < num_edges; x++)
+ /* Allocate a worklist array/queue. Entries are only added to the
+ list if they were not already on the list. So the size is
+ bounded by the number of basic blocks. */
+ qin = qout = worklist
+ = XNEWVEC (basic_block, n_basic_blocks);
+
+ /* Initialize a mapping from each edge to its index. */
+ for (i = 0; i < num_edges; i++)
+ INDEX_EDGE (edge_list, i)->aux = (void *) (size_t) i;
+
+ /* We want a maximal solution, so initially consider LATER true for
+ all edges. This allows propagation through a loop since the incoming
+ loop edge will have LATER set, so if all the other incoming edges
+ to the loop are set, then LATERIN will be set for the head of the
+ loop.
+
+ If the optimistic setting of LATER on that edge was incorrect (for
+ example the expression is ANTLOC in a block within the loop) then
+ this algorithm will detect it when we process the block at the head
+ of the optimistic edge. That will requeue the affected blocks. */
+ sbitmap_vector_ones (later, num_edges);
+
+ /* Note that even though we want an optimistic setting of LATER, we
+ do not want to be overly optimistic. Consider an outgoing edge from
+ the entry block. That edge should always have a LATER value the
+ same as EARLIEST for that edge. */
+ FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs)
+ sbitmap_copy (later[(size_t) e->aux], earliest[(size_t) e->aux]);
+
+ /* Add all the blocks to the worklist. This prevents an early exit from
+ the loop given our optimistic initialization of LATER above. */
+ FOR_EACH_BB (bb)
{
- succ = INDEX_EDGE_SUCC_BB (edge_list, x);
- pred = INDEX_EDGE_PRED_BB (edge_list, x);
- if (succ != EXIT_BLOCK_PTR)
- sbitmap_a_and_b (laterin[succ->index], laterin[succ->index],
- earliest[x]);
- /* We already know the correct value of later for edges from
- the entry node, so set it now. */
- if (pred == ENTRY_BLOCK_PTR)
- sbitmap_copy (later[x], earliest[x]);
+ *qin++ = bb;
+ bb->aux = bb;
}
- difference = sbitmap_alloc (n_exprs);
+ /* Note that we do not use the last allocated element for our queue,
+ as EXIT_BLOCK is never inserted into it. */
+ qin = worklist;
+ qend = &worklist[n_basic_blocks - NUM_FIXED_BLOCKS];
+ qlen = n_basic_blocks - NUM_FIXED_BLOCKS;
- while (!done)
+ /* Iterate until the worklist is empty. */
+ while (qlen)
{
- done = 1;
- for (x = 0; x < num_edges; x++)
- {
- pred = INDEX_EDGE_PRED_BB (edge_list, x);
- if (pred != ENTRY_BLOCK_PTR)
- {
- sbitmap_difference (difference, laterin[pred->index],
- antloc[pred->index]);
- if (sbitmap_a_or_b (later[x], difference, earliest[x]))
- done = 0;
- }
- }
- if (done)
- break;
-
- sbitmap_vector_ones (laterin, n_basic_blocks);
-
- for (x = 0; x < num_edges; x++)
- {
- succ = INDEX_EDGE_SUCC_BB (edge_list, x);
- if (succ != EXIT_BLOCK_PTR)
- sbitmap_a_and_b (laterin[succ->index], laterin[succ->index],
- later[x]);
- else
- /* We allocated an extra block for the exit node. */
- sbitmap_a_and_b (laterin[n_basic_blocks], laterin[n_basic_blocks],
- later[x]);
- }
+ /* Take the first entry off the worklist. */
+ bb = *qout++;
+ bb->aux = NULL;
+ qlen--;
+ if (qout >= qend)
+ qout = worklist;
+
+ /* Compute the intersection of LATERIN for each incoming edge to B. */
+ sbitmap_ones (laterin[bb->index]);
+ FOR_EACH_EDGE (e, ei, bb->preds)
+ sbitmap_a_and_b (laterin[bb->index], laterin[bb->index],
+ later[(size_t)e->aux]);
+
+ /* Calculate LATER for all outgoing edges. */
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ if (sbitmap_union_of_diff_cg (later[(size_t) e->aux],
+ earliest[(size_t) e->aux],
+ laterin[e->src->index],
+ antloc[e->src->index])
+ /* If LATER for an outgoing edge was changed, then we need
+ to add the target of the outgoing edge to the worklist. */
+ && e->dest != EXIT_BLOCK_PTR && e->dest->aux == 0)
+ {
+ *qin++ = e->dest;
+ e->dest->aux = e;
+ qlen++;
+ if (qin >= qend)
+ qin = worklist;
+ }
}
- free (difference);
+ /* Computation of insertion and deletion points requires computing LATERIN
+ for the EXIT block. We allocated an extra entry in the LATERIN array
+ for just this purpose. */
+ sbitmap_ones (laterin[last_basic_block]);
+ FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
+ sbitmap_a_and_b (laterin[last_basic_block],
+ laterin[last_basic_block],
+ later[(size_t) e->aux]);
+
+ clear_aux_for_edges ();
+ free (worklist);
}
/* Compute the insertion and deletion points for edge based LCM. */
+
static void
-compute_insert_delete (edge_list, antloc, later, laterin,
- insert, delete)
- struct edge_list *edge_list;
- sbitmap *antloc, *later, *laterin, *insert, *delete;
+compute_insert_delete (struct edge_list *edge_list, sbitmap *antloc,
+ sbitmap *later, sbitmap *laterin, sbitmap *insert,
+ sbitmap *del)
{
int x;
+ basic_block bb;
+
+ FOR_EACH_BB (bb)
+ sbitmap_difference (del[bb->index], antloc[bb->index],
+ laterin[bb->index]);
- for (x = 0; x < n_basic_blocks; x++)
- sbitmap_difference (delete[x], antloc[x], laterin[x]);
-
for (x = 0; x < NUM_EDGES (edge_list); x++)
{
basic_block b = INDEX_EDGE_SUCC_BB (edge_list, x);
+
if (b == EXIT_BLOCK_PTR)
- sbitmap_difference (insert[x], later[x], laterin[n_basic_blocks]);
+ sbitmap_difference (insert[x], later[x], laterin[last_basic_block]);
else
sbitmap_difference (insert[x], later[x], laterin[b->index]);
}
}
-/* Given local properties TRANSP, ANTLOC, AVOUT, KILL return the
- insert and delete vectors for edge based LCM. Returns an
- edgelist which is used to map the insert vector to what edge
- an expression should be inserted on. */
+/* Given local properties TRANSP, ANTLOC, AVOUT, KILL return the insert and
+ delete vectors for edge based LCM. Returns an edgelist which is used to
+ map the insert vector to what edge an expression should be inserted on. */
struct edge_list *
-pre_edge_lcm (file, n_exprs, transp, avloc, antloc, kill, insert, delete)
- FILE *file;
- int n_exprs;
- sbitmap *transp;
- sbitmap *avloc;
- sbitmap *antloc;
- sbitmap *kill;
- sbitmap **insert;
- sbitmap **delete;
+pre_edge_lcm (int n_exprs, sbitmap *transp,
+ sbitmap *avloc, sbitmap *antloc, sbitmap *kill,
+ sbitmap **insert, sbitmap **del)
{
sbitmap *antin, *antout, *earliest;
sbitmap *avin, *avout;
num_edges = NUM_EDGES (edge_list);
#ifdef LCM_DEBUG_INFO
- if (file)
+ if (dump_file)
{
- fprintf (file, "Edge List:\n");
- verify_edge_list (file, edge_list);
- print_edge_list (file, edge_list);
- dump_sbitmap_vector (file, "transp", "", transp, n_basic_blocks);
- dump_sbitmap_vector (file, "antloc", "", antloc, n_basic_blocks);
- dump_sbitmap_vector (file, "avloc", "", avloc, n_basic_blocks);
- dump_sbitmap_vector (file, "kill", "", kill, n_basic_blocks);
+ fprintf (dump_file, "Edge List:\n");
+ verify_edge_list (dump_file, edge_list);
+ print_edge_list (dump_file, edge_list);
+ dump_sbitmap_vector (dump_file, "transp", "", transp, last_basic_block);
+ dump_sbitmap_vector (dump_file, "antloc", "", antloc, last_basic_block);
+ dump_sbitmap_vector (dump_file, "avloc", "", avloc, last_basic_block);
+ dump_sbitmap_vector (dump_file, "kill", "", kill, last_basic_block);
}
#endif
/* Compute global availability. */
- avin = sbitmap_vector_alloc (n_basic_blocks, n_exprs);
- avout = sbitmap_vector_alloc (n_basic_blocks, n_exprs);
+ avin = sbitmap_vector_alloc (last_basic_block, n_exprs);
+ avout = sbitmap_vector_alloc (last_basic_block, n_exprs);
compute_available (avloc, kill, avout, avin);
-
- free (avin);
+ sbitmap_vector_free (avin);
/* Compute global anticipatability. */
- antin = sbitmap_vector_alloc (n_basic_blocks, n_exprs);
- antout = sbitmap_vector_alloc (n_basic_blocks, n_exprs);
+ antin = sbitmap_vector_alloc (last_basic_block, n_exprs);
+ antout = sbitmap_vector_alloc (last_basic_block, n_exprs);
compute_antinout_edge (antloc, transp, antin, antout);
#ifdef LCM_DEBUG_INFO
- if (file)
+ if (dump_file)
{
- dump_sbitmap_vector (file, "antin", "", antin, n_basic_blocks);
- dump_sbitmap_vector (file, "antout", "", antout, n_basic_blocks);
+ dump_sbitmap_vector (dump_file, "antin", "", antin, last_basic_block);
+ dump_sbitmap_vector (dump_file, "antout", "", antout, last_basic_block);
}
#endif
compute_earliest (edge_list, n_exprs, antin, antout, avout, kill, earliest);
#ifdef LCM_DEBUG_INFO
- if (file)
- dump_sbitmap_vector (file, "earliest", "", earliest, num_edges);
+ if (dump_file)
+ dump_sbitmap_vector (dump_file, "earliest", "", earliest, num_edges);
#endif
- free (antout);
- free (antin);
- free (avout);
+ sbitmap_vector_free (antout);
+ sbitmap_vector_free (antin);
+ sbitmap_vector_free (avout);
later = sbitmap_vector_alloc (num_edges, n_exprs);
+
/* Allocate an extra element for the exit block in the laterin vector. */
- laterin = sbitmap_vector_alloc (n_basic_blocks + 1, n_exprs);
- compute_laterin (edge_list, n_exprs, earliest, antloc, later, laterin);
+ laterin = sbitmap_vector_alloc (last_basic_block + 1, n_exprs);
+ compute_laterin (edge_list, earliest, antloc, later, laterin);
#ifdef LCM_DEBUG_INFO
- if (file)
+ if (dump_file)
{
- dump_sbitmap_vector (file, "laterin", "", laterin, n_basic_blocks + 1);
- dump_sbitmap_vector (file, "later", "", later, num_edges);
+ dump_sbitmap_vector (dump_file, "laterin", "", laterin, last_basic_block + 1);
+ dump_sbitmap_vector (dump_file, "later", "", later, num_edges);
}
#endif
- free (earliest);
+ sbitmap_vector_free (earliest);
*insert = sbitmap_vector_alloc (num_edges, n_exprs);
- *delete = sbitmap_vector_alloc (n_basic_blocks, n_exprs);
- compute_insert_delete (edge_list, antloc, later, laterin, *insert, *delete);
+ *del = sbitmap_vector_alloc (last_basic_block, n_exprs);
+ compute_insert_delete (edge_list, antloc, later, laterin, *insert, *del);
- free (laterin);
- free (later);
+ sbitmap_vector_free (laterin);
+ sbitmap_vector_free (later);
#ifdef LCM_DEBUG_INFO
- if (file)
+ if (dump_file)
{
- dump_sbitmap_vector (file, "pre_insert_map", "", *insert, num_edges);
- dump_sbitmap_vector (file, "pre_delete_map", "", *delete, n_basic_blocks);
+ dump_sbitmap_vector (dump_file, "pre_insert_map", "", *insert, num_edges);
+ dump_sbitmap_vector (dump_file, "pre_delete_map", "", *del,
+ last_basic_block);
}
#endif
/* Compute the AVIN and AVOUT vectors from the AVLOC and KILL vectors.
Return the number of passes we performed to iterate to a solution. */
-int
-compute_available (avloc, kill, avout, avin)
- sbitmap *avloc, *kill, *avout, *avin;
+
+void
+compute_available (sbitmap *avloc, sbitmap *kill, sbitmap *avout,
+ sbitmap *avin)
{
- int bb, changed, passes;
- int last = n_basic_blocks - 1;
-
- sbitmap_zero (avin[0]);
- sbitmap_copy (avout[0] /*dst*/, avloc[0] /*src*/);
-
- for (bb = 1; bb < n_basic_blocks; bb++)
- sbitmap_not (avout[bb], kill[bb]);
-
- passes = 0;
- changed = 1;
- while (changed)
+ edge e;
+ basic_block *worklist, *qin, *qout, *qend, bb;
+ unsigned int qlen;
+ edge_iterator ei;
+
+ /* Allocate a worklist array/queue. Entries are only added to the
+ list if they were not already on the list. So the size is
+ bounded by the number of basic blocks. */
+ qin = qout = worklist =
+ XNEWVEC (basic_block, n_basic_blocks - NUM_FIXED_BLOCKS);
+
+ /* We want a maximal solution. */
+ sbitmap_vector_ones (avout, last_basic_block);
+
+ /* Put every block on the worklist; this is necessary because of the
+ optimistic initialization of AVOUT above. */
+ FOR_EACH_BB (bb)
{
- changed = 0;
- for (bb = 1; bb < n_basic_blocks; bb++)
- {
- sbitmap_intersection_of_preds (avin[bb], avout, bb);
- changed |= sbitmap_union_of_diff (avout[bb], avloc[bb],
- avin[bb], kill[bb]);
- }
- passes++;
+ *qin++ = bb;
+ bb->aux = bb;
+ }
+
+ qin = worklist;
+ qend = &worklist[n_basic_blocks - NUM_FIXED_BLOCKS];
+ qlen = n_basic_blocks - NUM_FIXED_BLOCKS;
+
+ /* Mark blocks which are successors of the entry block so that we
+ can easily identify them below. */
+ FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs)
+ e->dest->aux = ENTRY_BLOCK_PTR;
+
+ /* Iterate until the worklist is empty. */
+ while (qlen)
+ {
+ /* Take the first entry off the worklist. */
+ bb = *qout++;
+ qlen--;
+
+ if (qout >= qend)
+ qout = worklist;
+
+ /* If one of the predecessor blocks is the ENTRY block, then the
+ intersection of avouts is the null set. We can identify such blocks
+ by the special value in the AUX field in the block structure. */
+ if (bb->aux == ENTRY_BLOCK_PTR)
+ /* Do not clear the aux field for blocks which are successors of the
+ ENTRY block. That way we never add then to the worklist again. */
+ sbitmap_zero (avin[bb->index]);
+ else
+ {
+ /* Clear the aux field of this block so that it can be added to
+ the worklist again if necessary. */
+ bb->aux = NULL;
+ sbitmap_intersection_of_preds (avin[bb->index], avout, bb->index);
+ }
+
+ if (sbitmap_union_of_diff_cg (avout[bb->index], avloc[bb->index],
+ avin[bb->index], kill[bb->index]))
+ /* If the out state of this block changed, then we need
+ to add the successors of this block to the worklist
+ if they are not already on the worklist. */
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ if (!e->dest->aux && e->dest != EXIT_BLOCK_PTR)
+ {
+ *qin++ = e->dest;
+ e->dest->aux = e;
+ qlen++;
+
+ if (qin >= qend)
+ qin = worklist;
+ }
}
- return passes;
+
+ clear_aux_for_edges ();
+ clear_aux_for_blocks ();
+ free (worklist);
}
/* Compute the farthest vector for edge based lcm. */
+
static void
-compute_farthest (edge_list, n_exprs, st_avout, st_avin, st_antin,
- kill, farthest)
- struct edge_list *edge_list;
- int n_exprs;
- sbitmap *st_avout, *st_avin, *st_antin, *kill, *farthest;
+compute_farthest (struct edge_list *edge_list, int n_exprs,
+ sbitmap *st_avout, sbitmap *st_avin, sbitmap *st_antin,
+ sbitmap *kill, sbitmap *farthest)
{
sbitmap difference, temp_bitmap;
- int x, num_edges;
+ int x, num_edges;
basic_block pred, succ;
num_edges = NUM_EDGES (edge_list);
else
{
if (pred == ENTRY_BLOCK_PTR)
- {
- sbitmap_zero (farthest[x]);
- }
+ sbitmap_zero (farthest[x]);
else
{
- sbitmap_difference (difference, st_avout[pred->index],
+ sbitmap_difference (difference, st_avout[pred->index],
st_antin[succ->index]);
sbitmap_not (temp_bitmap, st_avin[succ->index]);
- sbitmap_a_and_b_or_c (farthest[x], difference,
+ sbitmap_a_and_b_or_c (farthest[x], difference,
kill[succ->index], temp_bitmap);
}
}
}
- free (temp_bitmap);
- free (difference);
+
+ sbitmap_free (temp_bitmap);
+ sbitmap_free (difference);
}
-/* Compute nearer and nearerout vectors for edge based lcm. */
+/* Compute nearer and nearerout vectors for edge based lcm.
+
+ This is the mirror of compute_laterin, additional comments on the
+ implementation can be found before compute_laterin. */
+
static void
-compute_nearerout (edge_list, n_exprs,
- farthest, st_avloc, nearer, nearerout)
- struct edge_list *edge_list;
- int n_exprs;
- sbitmap *farthest, *st_avloc, *nearer, *nearerout;
+compute_nearerout (struct edge_list *edge_list, sbitmap *farthest,
+ sbitmap *st_avloc, sbitmap *nearer, sbitmap *nearerout)
{
- sbitmap difference, temp_bitmap;
- int x, num_edges;
- basic_block pred, succ;
- int done = 0;
+ int num_edges, i;
+ edge e;
+ basic_block *worklist, *tos, bb;
+ edge_iterator ei;
num_edges = NUM_EDGES (edge_list);
- /* nearout has an extra block allocated for the entry block. */
- sbitmap_vector_ones (nearerout, n_basic_blocks + 1);
- sbitmap_vector_zero (nearer, num_edges);
-
- /* Initialize nearerout to the intersection of FARTHEST for all edges
- from predecessors to this block. */
-
- for (x = 0; x < num_edges; x++)
+ /* Allocate a worklist array/queue. Entries are only added to the
+ list if they were not already on the list. So the size is
+ bounded by the number of basic blocks. */
+ tos = worklist = XNEWVEC (basic_block, n_basic_blocks + 1);
+
+ /* Initialize NEARER for each edge and build a mapping from an edge to
+ its index. */
+ for (i = 0; i < num_edges; i++)
+ INDEX_EDGE (edge_list, i)->aux = (void *) (size_t) i;
+
+ /* We want a maximal solution. */
+ sbitmap_vector_ones (nearer, num_edges);
+
+ /* Note that even though we want an optimistic setting of NEARER, we
+ do not want to be overly optimistic. Consider an incoming edge to
+ the exit block. That edge should always have a NEARER value the
+ same as FARTHEST for that edge. */
+ FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
+ sbitmap_copy (nearer[(size_t)e->aux], farthest[(size_t)e->aux]);
+
+ /* Add all the blocks to the worklist. This prevents an early exit
+ from the loop given our optimistic initialization of NEARER. */
+ FOR_EACH_BB (bb)
{
- succ = INDEX_EDGE_SUCC_BB (edge_list, x);
- pred = INDEX_EDGE_PRED_BB (edge_list, x);
- if (pred != ENTRY_BLOCK_PTR)
- {
- sbitmap_a_and_b (nearerout[pred->index], nearerout[pred->index],
- farthest[x]);
- }
- /* We already know the correct value of nearer for edges to
- the exit node. */
- if (succ == EXIT_BLOCK_PTR)
- sbitmap_copy (nearer[x], farthest[x]);
+ *tos++ = bb;
+ bb->aux = bb;
}
- difference = sbitmap_alloc (n_exprs);
-
- while (!done)
+ /* Iterate until the worklist is empty. */
+ while (tos != worklist)
{
- done = 1;
- for (x = 0; x < num_edges; x++)
- {
- succ = INDEX_EDGE_SUCC_BB (edge_list, x);
- if (succ != EXIT_BLOCK_PTR)
- {
- sbitmap_difference (difference, nearerout[succ->index],
- st_avloc[succ->index]);
- if (sbitmap_a_or_b (nearer[x], difference, farthest[x]))
- done = 0;
- }
- }
-
- if (done)
- break;
-
- sbitmap_vector_zero (nearerout, n_basic_blocks);
-
- for (x = 0; x < num_edges; x++)
- {
- pred = INDEX_EDGE_PRED_BB (edge_list, x);
- if (pred != ENTRY_BLOCK_PTR)
- sbitmap_a_and_b (nearerout[pred->index],
- nearerout[pred->index], nearer[x]);
- else
- sbitmap_a_and_b (nearerout[n_basic_blocks],
- nearerout[n_basic_blocks], nearer[x]);
- }
+ /* Take the first entry off the worklist. */
+ bb = *--tos;
+ bb->aux = NULL;
+
+ /* Compute the intersection of NEARER for each outgoing edge from B. */
+ sbitmap_ones (nearerout[bb->index]);
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ sbitmap_a_and_b (nearerout[bb->index], nearerout[bb->index],
+ nearer[(size_t) e->aux]);
+
+ /* Calculate NEARER for all incoming edges. */
+ FOR_EACH_EDGE (e, ei, bb->preds)
+ if (sbitmap_union_of_diff_cg (nearer[(size_t) e->aux],
+ farthest[(size_t) e->aux],
+ nearerout[e->dest->index],
+ st_avloc[e->dest->index])
+ /* If NEARER for an incoming edge was changed, then we need
+ to add the source of the incoming edge to the worklist. */
+ && e->src != ENTRY_BLOCK_PTR && e->src->aux == 0)
+ {
+ *tos++ = e->src;
+ e->src->aux = e;
+ }
}
- free (difference);
+ /* Computation of insertion and deletion points requires computing NEAREROUT
+ for the ENTRY block. We allocated an extra entry in the NEAREROUT array
+ for just this purpose. */
+ sbitmap_ones (nearerout[last_basic_block]);
+ FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs)
+ sbitmap_a_and_b (nearerout[last_basic_block],
+ nearerout[last_basic_block],
+ nearer[(size_t) e->aux]);
+
+ clear_aux_for_edges ();
+ free (tos);
}
/* Compute the insertion and deletion points for edge based LCM. */
+
static void
-compute_rev_insert_delete (edge_list, st_avloc, nearer, nearerout,
- insert, delete)
- struct edge_list *edge_list;
- sbitmap *st_avloc, *nearer, *nearerout, *insert, *delete;
+compute_rev_insert_delete (struct edge_list *edge_list, sbitmap *st_avloc,
+ sbitmap *nearer, sbitmap *nearerout,
+ sbitmap *insert, sbitmap *del)
{
int x;
+ basic_block bb;
+
+ FOR_EACH_BB (bb)
+ sbitmap_difference (del[bb->index], st_avloc[bb->index],
+ nearerout[bb->index]);
- for (x = 0; x < n_basic_blocks; x++)
- sbitmap_difference (delete[x], st_avloc[x], nearerout[x]);
-
for (x = 0; x < NUM_EDGES (edge_list); x++)
{
basic_block b = INDEX_EDGE_PRED_BB (edge_list, x);
if (b == ENTRY_BLOCK_PTR)
- sbitmap_difference (insert[x], nearer[x], nearerout[n_basic_blocks]);
+ sbitmap_difference (insert[x], nearer[x], nearerout[last_basic_block]);
else
sbitmap_difference (insert[x], nearer[x], nearerout[b->index]);
}
}
-/* Given local properties TRANSP, ST_AVLOC, ST_ANTLOC, KILL return the
+/* Given local properties TRANSP, ST_AVLOC, ST_ANTLOC, KILL return the
insert and delete vectors for edge based reverse LCM. Returns an
edgelist which is used to map the insert vector to what edge
an expression should be inserted on. */
struct edge_list *
-pre_edge_rev_lcm (file, n_exprs, transp, st_avloc, st_antloc, kill,
- insert, delete)
- FILE *file;
- int n_exprs;
- sbitmap *transp;
- sbitmap *st_avloc;
- sbitmap *st_antloc;
- sbitmap *kill;
- sbitmap **insert;
- sbitmap **delete;
+pre_edge_rev_lcm (int n_exprs, sbitmap *transp,
+ sbitmap *st_avloc, sbitmap *st_antloc, sbitmap *kill,
+ sbitmap **insert, sbitmap **del)
{
sbitmap *st_antin, *st_antout;
sbitmap *st_avout, *st_avin, *farthest;
sbitmap *nearer, *nearerout;
struct edge_list *edge_list;
- int x,num_edges;
+ int num_edges;
edge_list = create_edge_list ();
num_edges = NUM_EDGES (edge_list);
- st_antin = (sbitmap *) sbitmap_vector_alloc (n_basic_blocks, n_exprs);
- st_antout = (sbitmap *) sbitmap_vector_alloc (n_basic_blocks, n_exprs);
- sbitmap_vector_zero (st_antin, n_basic_blocks);
- sbitmap_vector_zero (st_antout, n_basic_blocks);
+ st_antin = sbitmap_vector_alloc (last_basic_block, n_exprs);
+ st_antout = sbitmap_vector_alloc (last_basic_block, n_exprs);
+ sbitmap_vector_zero (st_antin, last_basic_block);
+ sbitmap_vector_zero (st_antout, last_basic_block);
compute_antinout_edge (st_antloc, transp, st_antin, st_antout);
/* Compute global anticipatability. */
- st_avout = sbitmap_vector_alloc (n_basic_blocks, n_exprs);
- st_avin = sbitmap_vector_alloc (n_basic_blocks, n_exprs);
+ st_avout = sbitmap_vector_alloc (last_basic_block, n_exprs);
+ st_avin = sbitmap_vector_alloc (last_basic_block, n_exprs);
compute_available (st_avloc, kill, st_avout, st_avin);
#ifdef LCM_DEBUG_INFO
- if (file)
+ if (dump_file)
{
- fprintf (file, "Edge List:\n");
- verify_edge_list (file, edge_list);
- print_edge_list (file, edge_list);
- dump_sbitmap_vector (file, "transp", "", transp, n_basic_blocks);
- dump_sbitmap_vector (file, "st_avloc", "", st_avloc, n_basic_blocks);
- dump_sbitmap_vector (file, "st_antloc", "", st_antloc, n_basic_blocks);
- dump_sbitmap_vector (file, "st_antin", "", st_antin, n_basic_blocks);
- dump_sbitmap_vector (file, "st_antout", "", st_antout, n_basic_blocks);
- dump_sbitmap_vector (file, "st_kill", "", kill, n_basic_blocks);
+ fprintf (dump_file, "Edge List:\n");
+ verify_edge_list (dump_file, edge_list);
+ print_edge_list (dump_file, edge_list);
+ dump_sbitmap_vector (dump_file, "transp", "", transp, last_basic_block);
+ dump_sbitmap_vector (dump_file, "st_avloc", "", st_avloc, last_basic_block);
+ dump_sbitmap_vector (dump_file, "st_antloc", "", st_antloc, last_basic_block);
+ dump_sbitmap_vector (dump_file, "st_antin", "", st_antin, last_basic_block);
+ dump_sbitmap_vector (dump_file, "st_antout", "", st_antout, last_basic_block);
+ dump_sbitmap_vector (dump_file, "st_kill", "", kill, last_basic_block);
}
#endif
#ifdef LCM_DEBUG_INFO
- if (file)
+ if (dump_file)
{
- dump_sbitmap_vector (file, "st_avout", "", st_avout, n_basic_blocks);
- dump_sbitmap_vector (file, "st_avin", "", st_avin, n_basic_blocks);
+ dump_sbitmap_vector (dump_file, "st_avout", "", st_avout, last_basic_block);
+ dump_sbitmap_vector (dump_file, "st_avin", "", st_avin, last_basic_block);
}
#endif
/* Compute farthestness. */
farthest = sbitmap_vector_alloc (num_edges, n_exprs);
- compute_farthest (edge_list, n_exprs, st_avout, st_avin, st_antin,
+ compute_farthest (edge_list, n_exprs, st_avout, st_avin, st_antin,
kill, farthest);
#ifdef LCM_DEBUG_INFO
- if (file)
- dump_sbitmap_vector (file, "farthest", "", farthest, num_edges);
+ if (dump_file)
+ dump_sbitmap_vector (dump_file, "farthest", "", farthest, num_edges);
#endif
- free (st_avin);
- free (st_avout);
+ sbitmap_vector_free (st_antin);
+ sbitmap_vector_free (st_antout);
+
+ sbitmap_vector_free (st_avin);
+ sbitmap_vector_free (st_avout);
nearer = sbitmap_vector_alloc (num_edges, n_exprs);
+
/* Allocate an extra element for the entry block. */
- nearerout = sbitmap_vector_alloc (n_basic_blocks + 1, n_exprs);
- compute_nearerout (edge_list, n_exprs, farthest, st_avloc, nearer, nearerout);
+ nearerout = sbitmap_vector_alloc (last_basic_block + 1, n_exprs);
+ compute_nearerout (edge_list, farthest, st_avloc, nearer, nearerout);
#ifdef LCM_DEBUG_INFO
- if (file)
+ if (dump_file)
{
- dump_sbitmap_vector (file, "nearerout", "", nearerout,
- n_basic_blocks + 1);
- dump_sbitmap_vector (file, "nearer", "", nearer, num_edges);
+ dump_sbitmap_vector (dump_file, "nearerout", "", nearerout,
+ last_basic_block + 1);
+ dump_sbitmap_vector (dump_file, "nearer", "", nearer, num_edges);
}
#endif
- free (farthest);
+ sbitmap_vector_free (farthest);
*insert = sbitmap_vector_alloc (num_edges, n_exprs);
- *delete = sbitmap_vector_alloc (n_basic_blocks, n_exprs);
- compute_rev_insert_delete (edge_list, st_avloc, nearer, nearerout, *insert, *delete);
+ *del = sbitmap_vector_alloc (last_basic_block, n_exprs);
+ compute_rev_insert_delete (edge_list, st_avloc, nearer, nearerout,
+ *insert, *del);
- free (nearerout);
- free (nearer);
+ sbitmap_vector_free (nearerout);
+ sbitmap_vector_free (nearer);
#ifdef LCM_DEBUG_INFO
- if (file)
+ if (dump_file)
{
- dump_sbitmap_vector (file, "pre_insert_map", "", *insert, num_edges);
- dump_sbitmap_vector (file, "pre_delete_map", "", *delete, n_basic_blocks);
+ dump_sbitmap_vector (dump_file, "pre_insert_map", "", *insert, num_edges);
+ dump_sbitmap_vector (dump_file, "pre_delete_map", "", *del,
+ last_basic_block);
}
#endif
-
return edge_list;
}
+
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