1351 lines
40 KiB
C
1351 lines
40 KiB
C
/* Generic partial redundancy elimination with lazy code motion support.
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Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
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This file is part of GCC.
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GCC is free software; you can redistribute it and/or modify it under
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the terms of the GNU General Public License as published by the Free
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Software Foundation; either version 2, or (at your option) any later
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version.
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GCC is distributed in the hope that it will be useful, but WITHOUT ANY
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WARRANTY; without even the implied warranty of MERCHANTABILITY or
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FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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for more details.
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You should have received a copy of the GNU General Public License
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along with GCC; see the file COPYING. If not, write to the Free
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Software Foundation, 59 Temple Place - Suite 330, Boston, MA
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02111-1307, USA. */
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/* These routines are meant to be used by various optimization
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passes which can be modeled as lazy code motion problems.
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Including, but not limited to:
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* Traditional partial redundancy elimination.
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* Placement of caller/caller register save/restores.
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* Load/store motion.
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* Copy motion.
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* Conversion of flat register files to a stacked register
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model.
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* Dead load/store elimination.
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These routines accept as input:
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* Basic block information (number of blocks, lists of
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predecessors and successors). Note the granularity
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does not need to be basic block, they could be statements
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or functions.
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* Bitmaps of local properties (computed, transparent and
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anticipatable expressions).
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The output of these routines is bitmap of redundant computations
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and a bitmap of optimal placement points. */
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#include "config.h"
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#include "system.h"
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#include "rtl.h"
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#include "regs.h"
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#include "hard-reg-set.h"
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#include "flags.h"
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#include "real.h"
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#include "insn-config.h"
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#include "recog.h"
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#include "basic-block.h"
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#include "output.h"
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#include "tm_p.h"
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/* We want target macros for the mode switching code to be able to refer
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to instruction attribute values. */
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#include "insn-attr.h"
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/* Edge based LCM routines. */
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static void compute_antinout_edge PARAMS ((sbitmap *, sbitmap *,
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sbitmap *, sbitmap *));
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static void compute_earliest PARAMS ((struct edge_list *, int,
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sbitmap *, sbitmap *,
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sbitmap *, sbitmap *,
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sbitmap *));
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static void compute_laterin PARAMS ((struct edge_list *, sbitmap *,
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sbitmap *, sbitmap *,
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sbitmap *));
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static void compute_insert_delete PARAMS ((struct edge_list *edge_list,
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sbitmap *, sbitmap *,
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sbitmap *, sbitmap *,
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sbitmap *));
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/* Edge based LCM routines on a reverse flowgraph. */
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static void compute_farthest PARAMS ((struct edge_list *, int,
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sbitmap *, sbitmap *,
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sbitmap*, sbitmap *,
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sbitmap *));
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static void compute_nearerout PARAMS ((struct edge_list *, sbitmap *,
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sbitmap *, sbitmap *,
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sbitmap *));
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static void compute_rev_insert_delete PARAMS ((struct edge_list *edge_list,
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sbitmap *, sbitmap *,
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sbitmap *, sbitmap *,
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sbitmap *));
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/* Edge based lcm routines. */
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/* Compute expression anticipatability at entrance and exit of each block.
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This is done based on the flow graph, and not on the pred-succ lists.
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Other than that, its pretty much identical to compute_antinout. */
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static void
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compute_antinout_edge (antloc, transp, antin, antout)
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sbitmap *antloc;
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sbitmap *transp;
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sbitmap *antin;
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sbitmap *antout;
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{
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basic_block bb;
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edge e;
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basic_block *worklist, *qin, *qout, *qend;
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unsigned int qlen;
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/* Allocate a worklist array/queue. Entries are only added to the
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list if they were not already on the list. So the size is
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bounded by the number of basic blocks. */
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qin = qout = worklist
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= (basic_block *) xmalloc (sizeof (basic_block) * n_basic_blocks);
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/* We want a maximal solution, so make an optimistic initialization of
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ANTIN. */
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sbitmap_vector_ones (antin, last_basic_block);
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/* Put every block on the worklist; this is necessary because of the
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optimistic initialization of ANTIN above. */
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FOR_EACH_BB_REVERSE (bb)
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{
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*qin++ =bb;
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bb->aux = bb;
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}
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qin = worklist;
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qend = &worklist[n_basic_blocks];
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qlen = n_basic_blocks;
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/* Mark blocks which are predecessors of the exit block so that we
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can easily identify them below. */
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for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
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e->src->aux = EXIT_BLOCK_PTR;
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/* Iterate until the worklist is empty. */
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while (qlen)
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{
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/* Take the first entry off the worklist. */
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bb = *qout++;
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qlen--;
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if (qout >= qend)
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qout = worklist;
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if (bb->aux == EXIT_BLOCK_PTR)
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/* Do not clear the aux field for blocks which are predecessors of
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the EXIT block. That way we never add then to the worklist
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again. */
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sbitmap_zero (antout[bb->index]);
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else
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{
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/* Clear the aux field of this block so that it can be added to
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the worklist again if necessary. */
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bb->aux = NULL;
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sbitmap_intersection_of_succs (antout[bb->index], antin, bb->index);
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}
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if (sbitmap_a_or_b_and_c_cg (antin[bb->index], antloc[bb->index],
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transp[bb->index], antout[bb->index]))
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/* If the in state of this block changed, then we need
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to add the predecessors of this block to the worklist
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if they are not already on the worklist. */
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for (e = bb->pred; e; e = e->pred_next)
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if (!e->src->aux && e->src != ENTRY_BLOCK_PTR)
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{
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*qin++ = e->src;
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e->src->aux = e;
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qlen++;
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if (qin >= qend)
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qin = worklist;
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}
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}
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clear_aux_for_edges ();
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clear_aux_for_blocks ();
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free (worklist);
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}
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/* Compute the earliest vector for edge based lcm. */
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static void
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compute_earliest (edge_list, n_exprs, antin, antout, avout, kill, earliest)
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struct edge_list *edge_list;
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int n_exprs;
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sbitmap *antin, *antout, *avout, *kill, *earliest;
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{
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sbitmap difference, temp_bitmap;
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int x, num_edges;
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basic_block pred, succ;
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num_edges = NUM_EDGES (edge_list);
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difference = sbitmap_alloc (n_exprs);
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temp_bitmap = sbitmap_alloc (n_exprs);
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for (x = 0; x < num_edges; x++)
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{
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pred = INDEX_EDGE_PRED_BB (edge_list, x);
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succ = INDEX_EDGE_SUCC_BB (edge_list, x);
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if (pred == ENTRY_BLOCK_PTR)
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sbitmap_copy (earliest[x], antin[succ->index]);
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else
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{
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if (succ == EXIT_BLOCK_PTR)
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sbitmap_zero (earliest[x]);
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else
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{
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sbitmap_difference (difference, antin[succ->index],
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avout[pred->index]);
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sbitmap_not (temp_bitmap, antout[pred->index]);
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sbitmap_a_and_b_or_c (earliest[x], difference,
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kill[pred->index], temp_bitmap);
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}
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}
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}
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sbitmap_free (temp_bitmap);
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sbitmap_free (difference);
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}
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/* later(p,s) is dependent on the calculation of laterin(p).
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laterin(p) is dependent on the calculation of later(p2,p).
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laterin(ENTRY) is defined as all 0's
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later(ENTRY, succs(ENTRY)) are defined using laterin(ENTRY)
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laterin(succs(ENTRY)) is defined by later(ENTRY, succs(ENTRY)).
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If we progress in this manner, starting with all basic blocks
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in the work list, anytime we change later(bb), we need to add
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succs(bb) to the worklist if they are not already on the worklist.
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Boundary conditions:
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We prime the worklist all the normal basic blocks. The ENTRY block can
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never be added to the worklist since it is never the successor of any
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block. We explicitly prevent the EXIT block from being added to the
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worklist.
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We optimistically initialize LATER. That is the only time this routine
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will compute LATER for an edge out of the entry block since the entry
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block is never on the worklist. Thus, LATERIN is neither used nor
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computed for the ENTRY block.
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Since the EXIT block is never added to the worklist, we will neither
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use nor compute LATERIN for the exit block. Edges which reach the
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EXIT block are handled in the normal fashion inside the loop. However,
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the insertion/deletion computation needs LATERIN(EXIT), so we have
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to compute it. */
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static void
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compute_laterin (edge_list, earliest, antloc, later, laterin)
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struct edge_list *edge_list;
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sbitmap *earliest, *antloc, *later, *laterin;
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{
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int num_edges, i;
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edge e;
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basic_block *worklist, *qin, *qout, *qend, bb;
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unsigned int qlen;
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num_edges = NUM_EDGES (edge_list);
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/* Allocate a worklist array/queue. Entries are only added to the
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list if they were not already on the list. So the size is
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bounded by the number of basic blocks. */
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qin = qout = worklist
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= (basic_block *) xmalloc (sizeof (basic_block) * (n_basic_blocks + 1));
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/* Initialize a mapping from each edge to its index. */
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for (i = 0; i < num_edges; i++)
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INDEX_EDGE (edge_list, i)->aux = (void *) (size_t) i;
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/* We want a maximal solution, so initially consider LATER true for
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all edges. This allows propagation through a loop since the incoming
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loop edge will have LATER set, so if all the other incoming edges
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to the loop are set, then LATERIN will be set for the head of the
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loop.
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If the optimistic setting of LATER on that edge was incorrect (for
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example the expression is ANTLOC in a block within the loop) then
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this algorithm will detect it when we process the block at the head
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of the optimistic edge. That will requeue the affected blocks. */
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sbitmap_vector_ones (later, num_edges);
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/* Note that even though we want an optimistic setting of LATER, we
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do not want to be overly optimistic. Consider an outgoing edge from
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the entry block. That edge should always have a LATER value the
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same as EARLIEST for that edge. */
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for (e = ENTRY_BLOCK_PTR->succ; e; e = e->succ_next)
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sbitmap_copy (later[(size_t) e->aux], earliest[(size_t) e->aux]);
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/* Add all the blocks to the worklist. This prevents an early exit from
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the loop given our optimistic initialization of LATER above. */
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FOR_EACH_BB (bb)
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{
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*qin++ = bb;
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bb->aux = bb;
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}
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qin = worklist;
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/* Note that we do not use the last allocated element for our queue,
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as EXIT_BLOCK is never inserted into it. In fact the above allocation
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of n_basic_blocks + 1 elements is not encessary. */
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qend = &worklist[n_basic_blocks];
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qlen = n_basic_blocks;
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/* Iterate until the worklist is empty. */
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while (qlen)
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{
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/* Take the first entry off the worklist. */
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bb = *qout++;
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bb->aux = NULL;
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qlen--;
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if (qout >= qend)
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qout = worklist;
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/* Compute the intersection of LATERIN for each incoming edge to B. */
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sbitmap_ones (laterin[bb->index]);
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for (e = bb->pred; e != NULL; e = e->pred_next)
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sbitmap_a_and_b (laterin[bb->index], laterin[bb->index], later[(size_t)e->aux]);
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/* Calculate LATER for all outgoing edges. */
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for (e = bb->succ; e != NULL; e = e->succ_next)
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if (sbitmap_union_of_diff_cg (later[(size_t) e->aux],
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earliest[(size_t) e->aux],
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laterin[e->src->index],
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antloc[e->src->index])
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/* If LATER for an outgoing edge was changed, then we need
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to add the target of the outgoing edge to the worklist. */
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&& e->dest != EXIT_BLOCK_PTR && e->dest->aux == 0)
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{
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*qin++ = e->dest;
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e->dest->aux = e;
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qlen++;
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if (qin >= qend)
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qin = worklist;
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}
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}
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/* Computation of insertion and deletion points requires computing LATERIN
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for the EXIT block. We allocated an extra entry in the LATERIN array
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for just this purpose. */
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sbitmap_ones (laterin[last_basic_block]);
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for (e = EXIT_BLOCK_PTR->pred; e != NULL; e = e->pred_next)
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sbitmap_a_and_b (laterin[last_basic_block],
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laterin[last_basic_block],
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later[(size_t) e->aux]);
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clear_aux_for_edges ();
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free (worklist);
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}
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/* Compute the insertion and deletion points for edge based LCM. */
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static void
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compute_insert_delete (edge_list, antloc, later, laterin,
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insert, delete)
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struct edge_list *edge_list;
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sbitmap *antloc, *later, *laterin, *insert, *delete;
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{
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int x;
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basic_block bb;
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FOR_EACH_BB (bb)
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sbitmap_difference (delete[bb->index], antloc[bb->index], laterin[bb->index]);
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for (x = 0; x < NUM_EDGES (edge_list); x++)
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{
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basic_block b = INDEX_EDGE_SUCC_BB (edge_list, x);
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if (b == EXIT_BLOCK_PTR)
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sbitmap_difference (insert[x], later[x], laterin[last_basic_block]);
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else
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sbitmap_difference (insert[x], later[x], laterin[b->index]);
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}
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}
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/* Given local properties TRANSP, ANTLOC, AVOUT, KILL return the insert and
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delete vectors for edge based LCM. Returns an edgelist which is used to
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map the insert vector to what edge an expression should be inserted on. */
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struct edge_list *
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pre_edge_lcm (file, n_exprs, transp, avloc, antloc, kill, insert, delete)
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FILE *file ATTRIBUTE_UNUSED;
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int n_exprs;
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sbitmap *transp;
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sbitmap *avloc;
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sbitmap *antloc;
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sbitmap *kill;
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sbitmap **insert;
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sbitmap **delete;
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{
|
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sbitmap *antin, *antout, *earliest;
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sbitmap *avin, *avout;
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sbitmap *later, *laterin;
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struct edge_list *edge_list;
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int num_edges;
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edge_list = create_edge_list ();
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num_edges = NUM_EDGES (edge_list);
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||
|
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#ifdef LCM_DEBUG_INFO
|
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if (file)
|
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{
|
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fprintf (file, "Edge List:\n");
|
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verify_edge_list (file, edge_list);
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print_edge_list (file, edge_list);
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dump_sbitmap_vector (file, "transp", "", transp, last_basic_block);
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dump_sbitmap_vector (file, "antloc", "", antloc, last_basic_block);
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dump_sbitmap_vector (file, "avloc", "", avloc, last_basic_block);
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dump_sbitmap_vector (file, "kill", "", kill, last_basic_block);
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}
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#endif
|
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|
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/* Compute global availability. */
|
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avin = sbitmap_vector_alloc (last_basic_block, n_exprs);
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||
avout = sbitmap_vector_alloc (last_basic_block, n_exprs);
|
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compute_available (avloc, kill, avout, avin);
|
||
sbitmap_vector_free (avin);
|
||
|
||
/* Compute global anticipatability. */
|
||
antin = sbitmap_vector_alloc (last_basic_block, n_exprs);
|
||
antout = sbitmap_vector_alloc (last_basic_block, n_exprs);
|
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compute_antinout_edge (antloc, transp, antin, antout);
|
||
|
||
#ifdef LCM_DEBUG_INFO
|
||
if (file)
|
||
{
|
||
dump_sbitmap_vector (file, "antin", "", antin, last_basic_block);
|
||
dump_sbitmap_vector (file, "antout", "", antout, last_basic_block);
|
||
}
|
||
#endif
|
||
|
||
/* Compute earliestness. */
|
||
earliest = sbitmap_vector_alloc (num_edges, n_exprs);
|
||
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);
|
||
#endif
|
||
|
||
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 (last_basic_block + 1, n_exprs);
|
||
compute_laterin (edge_list, earliest, antloc, later, laterin);
|
||
|
||
#ifdef LCM_DEBUG_INFO
|
||
if (file)
|
||
{
|
||
dump_sbitmap_vector (file, "laterin", "", laterin, last_basic_block + 1);
|
||
dump_sbitmap_vector (file, "later", "", later, num_edges);
|
||
}
|
||
#endif
|
||
|
||
sbitmap_vector_free (earliest);
|
||
|
||
*insert = sbitmap_vector_alloc (num_edges, n_exprs);
|
||
*delete = sbitmap_vector_alloc (last_basic_block, n_exprs);
|
||
compute_insert_delete (edge_list, antloc, later, laterin, *insert, *delete);
|
||
|
||
sbitmap_vector_free (laterin);
|
||
sbitmap_vector_free (later);
|
||
|
||
#ifdef LCM_DEBUG_INFO
|
||
if (file)
|
||
{
|
||
dump_sbitmap_vector (file, "pre_insert_map", "", *insert, num_edges);
|
||
dump_sbitmap_vector (file, "pre_delete_map", "", *delete,
|
||
last_basic_block);
|
||
}
|
||
#endif
|
||
|
||
return edge_list;
|
||
}
|
||
|
||
/* Compute the AVIN and AVOUT vectors from the AVLOC and KILL vectors.
|
||
Return the number of passes we performed to iterate to a solution. */
|
||
|
||
void
|
||
compute_available (avloc, kill, avout, avin)
|
||
sbitmap *avloc, *kill, *avout, *avin;
|
||
{
|
||
edge e;
|
||
basic_block *worklist, *qin, *qout, *qend, bb;
|
||
unsigned int qlen;
|
||
|
||
/* 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
|
||
= (basic_block *) xmalloc (sizeof (basic_block) * n_basic_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)
|
||
{
|
||
*qin++ = bb;
|
||
bb->aux = bb;
|
||
}
|
||
|
||
qin = worklist;
|
||
qend = &worklist[n_basic_blocks];
|
||
qlen = n_basic_blocks;
|
||
|
||
/* Mark blocks which are successors of the entry block so that we
|
||
can easily identify them below. */
|
||
for (e = ENTRY_BLOCK_PTR->succ; e; e = e->succ_next)
|
||
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 (e = bb->succ; e; e = e->succ_next)
|
||
if (!e->dest->aux && e->dest != EXIT_BLOCK_PTR)
|
||
{
|
||
*qin++ = e->dest;
|
||
e->dest->aux = e;
|
||
qlen++;
|
||
|
||
if (qin >= qend)
|
||
qin = worklist;
|
||
}
|
||
}
|
||
|
||
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;
|
||
{
|
||
sbitmap difference, temp_bitmap;
|
||
int x, num_edges;
|
||
basic_block pred, succ;
|
||
|
||
num_edges = NUM_EDGES (edge_list);
|
||
|
||
difference = sbitmap_alloc (n_exprs);
|
||
temp_bitmap = sbitmap_alloc (n_exprs);
|
||
|
||
for (x = 0; x < num_edges; x++)
|
||
{
|
||
pred = INDEX_EDGE_PRED_BB (edge_list, x);
|
||
succ = INDEX_EDGE_SUCC_BB (edge_list, x);
|
||
if (succ == EXIT_BLOCK_PTR)
|
||
sbitmap_copy (farthest[x], st_avout[pred->index]);
|
||
else
|
||
{
|
||
if (pred == ENTRY_BLOCK_PTR)
|
||
sbitmap_zero (farthest[x]);
|
||
else
|
||
{
|
||
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,
|
||
kill[succ->index], temp_bitmap);
|
||
}
|
||
}
|
||
}
|
||
|
||
sbitmap_free (temp_bitmap);
|
||
sbitmap_free (difference);
|
||
}
|
||
|
||
/* 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, farthest, st_avloc, nearer, nearerout)
|
||
struct edge_list *edge_list;
|
||
sbitmap *farthest, *st_avloc, *nearer, *nearerout;
|
||
{
|
||
int num_edges, i;
|
||
edge e;
|
||
basic_block *worklist, *tos, bb;
|
||
|
||
num_edges = NUM_EDGES (edge_list);
|
||
|
||
/* 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
|
||
= (basic_block *) xmalloc (sizeof (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 (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
|
||
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)
|
||
{
|
||
*tos++ = bb;
|
||
bb->aux = bb;
|
||
}
|
||
|
||
/* Iterate until the worklist is empty. */
|
||
while (tos != worklist)
|
||
{
|
||
/* 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 (e = bb->succ; e != NULL; e = e->succ_next)
|
||
sbitmap_a_and_b (nearerout[bb->index], nearerout[bb->index],
|
||
nearer[(size_t) e->aux]);
|
||
|
||
/* Calculate NEARER for all incoming edges. */
|
||
for (e = bb->pred; e != NULL; e = e->pred_next)
|
||
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;
|
||
}
|
||
}
|
||
|
||
/* 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 (e = ENTRY_BLOCK_PTR->succ; e != NULL; e = e->succ_next)
|
||
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;
|
||
{
|
||
int x;
|
||
basic_block bb;
|
||
|
||
FOR_EACH_BB (bb)
|
||
sbitmap_difference (delete[bb->index], st_avloc[bb->index], nearerout[bb->index]);
|
||
|
||
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[last_basic_block]);
|
||
else
|
||
sbitmap_difference (insert[x], nearer[x], nearerout[b->index]);
|
||
}
|
||
}
|
||
|
||
/* 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 ATTRIBUTE_UNUSED;
|
||
int n_exprs;
|
||
sbitmap *transp;
|
||
sbitmap *st_avloc;
|
||
sbitmap *st_antloc;
|
||
sbitmap *kill;
|
||
sbitmap **insert;
|
||
sbitmap **delete;
|
||
{
|
||
sbitmap *st_antin, *st_antout;
|
||
sbitmap *st_avout, *st_avin, *farthest;
|
||
sbitmap *nearer, *nearerout;
|
||
struct edge_list *edge_list;
|
||
int num_edges;
|
||
|
||
edge_list = create_edge_list ();
|
||
num_edges = NUM_EDGES (edge_list);
|
||
|
||
st_antin = (sbitmap *) sbitmap_vector_alloc (last_basic_block, n_exprs);
|
||
st_antout = (sbitmap *) 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 (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)
|
||
{
|
||
fprintf (file, "Edge List:\n");
|
||
verify_edge_list (file, edge_list);
|
||
print_edge_list (file, edge_list);
|
||
dump_sbitmap_vector (file, "transp", "", transp, last_basic_block);
|
||
dump_sbitmap_vector (file, "st_avloc", "", st_avloc, last_basic_block);
|
||
dump_sbitmap_vector (file, "st_antloc", "", st_antloc, last_basic_block);
|
||
dump_sbitmap_vector (file, "st_antin", "", st_antin, last_basic_block);
|
||
dump_sbitmap_vector (file, "st_antout", "", st_antout, last_basic_block);
|
||
dump_sbitmap_vector (file, "st_kill", "", kill, last_basic_block);
|
||
}
|
||
#endif
|
||
|
||
#ifdef LCM_DEBUG_INFO
|
||
if (file)
|
||
{
|
||
dump_sbitmap_vector (file, "st_avout", "", st_avout, last_basic_block);
|
||
dump_sbitmap_vector (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,
|
||
kill, farthest);
|
||
|
||
#ifdef LCM_DEBUG_INFO
|
||
if (file)
|
||
dump_sbitmap_vector (file, "farthest", "", farthest, num_edges);
|
||
#endif
|
||
|
||
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 (last_basic_block + 1, n_exprs);
|
||
compute_nearerout (edge_list, farthest, st_avloc, nearer, nearerout);
|
||
|
||
#ifdef LCM_DEBUG_INFO
|
||
if (file)
|
||
{
|
||
dump_sbitmap_vector (file, "nearerout", "", nearerout,
|
||
last_basic_block + 1);
|
||
dump_sbitmap_vector (file, "nearer", "", nearer, num_edges);
|
||
}
|
||
#endif
|
||
|
||
sbitmap_vector_free (farthest);
|
||
|
||
*insert = sbitmap_vector_alloc (num_edges, n_exprs);
|
||
*delete = sbitmap_vector_alloc (last_basic_block, n_exprs);
|
||
compute_rev_insert_delete (edge_list, st_avloc, nearer, nearerout,
|
||
*insert, *delete);
|
||
|
||
sbitmap_vector_free (nearerout);
|
||
sbitmap_vector_free (nearer);
|
||
|
||
#ifdef LCM_DEBUG_INFO
|
||
if (file)
|
||
{
|
||
dump_sbitmap_vector (file, "pre_insert_map", "", *insert, num_edges);
|
||
dump_sbitmap_vector (file, "pre_delete_map", "", *delete,
|
||
last_basic_block);
|
||
}
|
||
#endif
|
||
return edge_list;
|
||
}
|
||
|
||
/* Mode switching:
|
||
|
||
The algorithm for setting the modes consists of scanning the insn list
|
||
and finding all the insns which require a specific mode. Each insn gets
|
||
a unique struct seginfo element. These structures are inserted into a list
|
||
for each basic block. For each entity, there is an array of bb_info over
|
||
the flow graph basic blocks (local var 'bb_info'), and contains a list
|
||
of all insns within that basic block, in the order they are encountered.
|
||
|
||
For each entity, any basic block WITHOUT any insns requiring a specific
|
||
mode are given a single entry, without a mode. (Each basic block
|
||
in the flow graph must have at least one entry in the segment table.)
|
||
|
||
The LCM algorithm is then run over the flow graph to determine where to
|
||
place the sets to the highest-priority value in respect of first the first
|
||
insn in any one block. Any adjustments required to the transparancy
|
||
vectors are made, then the next iteration starts for the next-lower
|
||
priority mode, till for each entity all modes are exhasted.
|
||
|
||
More details are located in the code for optimize_mode_switching(). */
|
||
|
||
/* This structure contains the information for each insn which requires
|
||
either single or double mode to be set.
|
||
MODE is the mode this insn must be executed in.
|
||
INSN_PTR is the insn to be executed (may be the note that marks the
|
||
beginning of a basic block).
|
||
BBNUM is the flow graph basic block this insn occurs in.
|
||
NEXT is the next insn in the same basic block. */
|
||
struct seginfo
|
||
{
|
||
int mode;
|
||
rtx insn_ptr;
|
||
int bbnum;
|
||
struct seginfo *next;
|
||
HARD_REG_SET regs_live;
|
||
};
|
||
|
||
struct bb_info
|
||
{
|
||
struct seginfo *seginfo;
|
||
int computing;
|
||
};
|
||
|
||
/* These bitmaps are used for the LCM algorithm. */
|
||
|
||
#ifdef OPTIMIZE_MODE_SWITCHING
|
||
static sbitmap *antic;
|
||
static sbitmap *transp;
|
||
static sbitmap *comp;
|
||
static sbitmap *delete;
|
||
static sbitmap *insert;
|
||
|
||
static struct seginfo * new_seginfo PARAMS ((int, rtx, int, HARD_REG_SET));
|
||
static void add_seginfo PARAMS ((struct bb_info *, struct seginfo *));
|
||
static void reg_dies PARAMS ((rtx, HARD_REG_SET));
|
||
static void reg_becomes_live PARAMS ((rtx, rtx, void *));
|
||
static void make_preds_opaque PARAMS ((basic_block, int));
|
||
#endif
|
||
|
||
#ifdef OPTIMIZE_MODE_SWITCHING
|
||
|
||
/* This function will allocate a new BBINFO structure, initialized
|
||
with the MODE, INSN, and basic block BB parameters. */
|
||
|
||
static struct seginfo *
|
||
new_seginfo (mode, insn, bb, regs_live)
|
||
int mode;
|
||
rtx insn;
|
||
int bb;
|
||
HARD_REG_SET regs_live;
|
||
{
|
||
struct seginfo *ptr;
|
||
ptr = xmalloc (sizeof (struct seginfo));
|
||
ptr->mode = mode;
|
||
ptr->insn_ptr = insn;
|
||
ptr->bbnum = bb;
|
||
ptr->next = NULL;
|
||
COPY_HARD_REG_SET (ptr->regs_live, regs_live);
|
||
return ptr;
|
||
}
|
||
|
||
/* Add a seginfo element to the end of a list.
|
||
HEAD is a pointer to the list beginning.
|
||
INFO is the structure to be linked in. */
|
||
|
||
static void
|
||
add_seginfo (head, info)
|
||
struct bb_info *head;
|
||
struct seginfo *info;
|
||
{
|
||
struct seginfo *ptr;
|
||
|
||
if (head->seginfo == NULL)
|
||
head->seginfo = info;
|
||
else
|
||
{
|
||
ptr = head->seginfo;
|
||
while (ptr->next != NULL)
|
||
ptr = ptr->next;
|
||
ptr->next = info;
|
||
}
|
||
}
|
||
|
||
/* Make all predecessors of basic block B opaque, recursively, till we hit
|
||
some that are already non-transparent, or an edge where aux is set; that
|
||
denotes that a mode set is to be done on that edge.
|
||
J is the bit number in the bitmaps that corresponds to the entity that
|
||
we are currently handling mode-switching for. */
|
||
|
||
static void
|
||
make_preds_opaque (b, j)
|
||
basic_block b;
|
||
int j;
|
||
{
|
||
edge e;
|
||
|
||
for (e = b->pred; e; e = e->pred_next)
|
||
{
|
||
basic_block pb = e->src;
|
||
|
||
if (e->aux || ! TEST_BIT (transp[pb->index], j))
|
||
continue;
|
||
|
||
RESET_BIT (transp[pb->index], j);
|
||
make_preds_opaque (pb, j);
|
||
}
|
||
}
|
||
|
||
/* Record in LIVE that register REG died. */
|
||
|
||
static void
|
||
reg_dies (reg, live)
|
||
rtx reg;
|
||
HARD_REG_SET live;
|
||
{
|
||
int regno, nregs;
|
||
|
||
if (GET_CODE (reg) != REG)
|
||
return;
|
||
|
||
regno = REGNO (reg);
|
||
if (regno < FIRST_PSEUDO_REGISTER)
|
||
for (nregs = HARD_REGNO_NREGS (regno, GET_MODE (reg)) - 1; nregs >= 0;
|
||
nregs--)
|
||
CLEAR_HARD_REG_BIT (live, regno + nregs);
|
||
}
|
||
|
||
/* Record in LIVE that register REG became live.
|
||
This is called via note_stores. */
|
||
|
||
static void
|
||
reg_becomes_live (reg, setter, live)
|
||
rtx reg;
|
||
rtx setter ATTRIBUTE_UNUSED;
|
||
void *live;
|
||
{
|
||
int regno, nregs;
|
||
|
||
if (GET_CODE (reg) == SUBREG)
|
||
reg = SUBREG_REG (reg);
|
||
|
||
if (GET_CODE (reg) != REG)
|
||
return;
|
||
|
||
regno = REGNO (reg);
|
||
if (regno < FIRST_PSEUDO_REGISTER)
|
||
for (nregs = HARD_REGNO_NREGS (regno, GET_MODE (reg)) - 1; nregs >= 0;
|
||
nregs--)
|
||
SET_HARD_REG_BIT (* (HARD_REG_SET *) live, regno + nregs);
|
||
}
|
||
|
||
/* Find all insns that need a particular mode setting, and insert the
|
||
necessary mode switches. Return true if we did work. */
|
||
|
||
int
|
||
optimize_mode_switching (file)
|
||
FILE *file;
|
||
{
|
||
rtx insn;
|
||
int e;
|
||
basic_block bb;
|
||
int need_commit = 0;
|
||
sbitmap *kill;
|
||
struct edge_list *edge_list;
|
||
static const int num_modes[] = NUM_MODES_FOR_MODE_SWITCHING;
|
||
#define N_ENTITIES ARRAY_SIZE (num_modes)
|
||
int entity_map[N_ENTITIES];
|
||
struct bb_info *bb_info[N_ENTITIES];
|
||
int i, j;
|
||
int n_entities;
|
||
int max_num_modes = 0;
|
||
bool emited = false;
|
||
basic_block post_entry ATTRIBUTE_UNUSED, pre_exit ATTRIBUTE_UNUSED;
|
||
|
||
clear_bb_flags ();
|
||
|
||
for (e = N_ENTITIES - 1, n_entities = 0; e >= 0; e--)
|
||
if (OPTIMIZE_MODE_SWITCHING (e))
|
||
{
|
||
int entry_exit_extra = 0;
|
||
|
||
/* Create the list of segments within each basic block.
|
||
If NORMAL_MODE is defined, allow for two extra
|
||
blocks split from the entry and exit block. */
|
||
#ifdef NORMAL_MODE
|
||
entry_exit_extra = 2;
|
||
#endif
|
||
bb_info[n_entities]
|
||
= (struct bb_info *) xcalloc (last_basic_block + entry_exit_extra,
|
||
sizeof **bb_info);
|
||
entity_map[n_entities++] = e;
|
||
if (num_modes[e] > max_num_modes)
|
||
max_num_modes = num_modes[e];
|
||
}
|
||
|
||
if (! n_entities)
|
||
return 0;
|
||
|
||
#ifdef NORMAL_MODE
|
||
{
|
||
/* Split the edge from the entry block and the fallthrough edge to the
|
||
exit block, so that we can note that there NORMAL_MODE is supplied /
|
||
required. */
|
||
edge eg;
|
||
post_entry = split_edge (ENTRY_BLOCK_PTR->succ);
|
||
/* The only non-call predecessor at this stage is a block with a
|
||
fallthrough edge; there can be at most one, but there could be
|
||
none at all, e.g. when exit is called. */
|
||
for (pre_exit = 0, eg = EXIT_BLOCK_PTR->pred; eg; eg = eg->pred_next)
|
||
if (eg->flags & EDGE_FALLTHRU)
|
||
{
|
||
regset live_at_end = eg->src->global_live_at_end;
|
||
|
||
if (pre_exit)
|
||
abort ();
|
||
pre_exit = split_edge (eg);
|
||
COPY_REG_SET (pre_exit->global_live_at_start, live_at_end);
|
||
COPY_REG_SET (pre_exit->global_live_at_end, live_at_end);
|
||
}
|
||
}
|
||
#endif
|
||
|
||
/* Create the bitmap vectors. */
|
||
|
||
antic = sbitmap_vector_alloc (last_basic_block, n_entities);
|
||
transp = sbitmap_vector_alloc (last_basic_block, n_entities);
|
||
comp = sbitmap_vector_alloc (last_basic_block, n_entities);
|
||
|
||
sbitmap_vector_ones (transp, last_basic_block);
|
||
|
||
for (j = n_entities - 1; j >= 0; j--)
|
||
{
|
||
int e = entity_map[j];
|
||
int no_mode = num_modes[e];
|
||
struct bb_info *info = bb_info[j];
|
||
|
||
/* Determine what the first use (if any) need for a mode of entity E is.
|
||
This will be the mode that is anticipatable for this block.
|
||
Also compute the initial transparency settings. */
|
||
FOR_EACH_BB (bb)
|
||
{
|
||
struct seginfo *ptr;
|
||
int last_mode = no_mode;
|
||
HARD_REG_SET live_now;
|
||
|
||
REG_SET_TO_HARD_REG_SET (live_now,
|
||
bb->global_live_at_start);
|
||
for (insn = bb->head;
|
||
insn != NULL && insn != NEXT_INSN (bb->end);
|
||
insn = NEXT_INSN (insn))
|
||
{
|
||
if (INSN_P (insn))
|
||
{
|
||
int mode = MODE_NEEDED (e, insn);
|
||
rtx link;
|
||
|
||
if (mode != no_mode && mode != last_mode)
|
||
{
|
||
last_mode = mode;
|
||
ptr = new_seginfo (mode, insn, bb->index, live_now);
|
||
add_seginfo (info + bb->index, ptr);
|
||
RESET_BIT (transp[bb->index], j);
|
||
}
|
||
|
||
/* Update LIVE_NOW. */
|
||
for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
|
||
if (REG_NOTE_KIND (link) == REG_DEAD)
|
||
reg_dies (XEXP (link, 0), live_now);
|
||
|
||
note_stores (PATTERN (insn), reg_becomes_live, &live_now);
|
||
for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
|
||
if (REG_NOTE_KIND (link) == REG_UNUSED)
|
||
reg_dies (XEXP (link, 0), live_now);
|
||
}
|
||
}
|
||
|
||
info[bb->index].computing = last_mode;
|
||
/* Check for blocks without ANY mode requirements. */
|
||
if (last_mode == no_mode)
|
||
{
|
||
ptr = new_seginfo (no_mode, bb->end, bb->index, live_now);
|
||
add_seginfo (info + bb->index, ptr);
|
||
}
|
||
}
|
||
#ifdef NORMAL_MODE
|
||
{
|
||
int mode = NORMAL_MODE (e);
|
||
|
||
if (mode != no_mode)
|
||
{
|
||
bb = post_entry;
|
||
|
||
/* By always making this nontransparent, we save
|
||
an extra check in make_preds_opaque. We also
|
||
need this to avoid confusing pre_edge_lcm when
|
||
antic is cleared but transp and comp are set. */
|
||
RESET_BIT (transp[bb->index], j);
|
||
|
||
/* Insert a fake computing definition of MODE into entry
|
||
blocks which compute no mode. This represents the mode on
|
||
entry. */
|
||
info[bb->index].computing = mode;
|
||
|
||
if (pre_exit)
|
||
info[pre_exit->index].seginfo->mode = mode;
|
||
}
|
||
}
|
||
#endif /* NORMAL_MODE */
|
||
}
|
||
|
||
kill = sbitmap_vector_alloc (last_basic_block, n_entities);
|
||
for (i = 0; i < max_num_modes; i++)
|
||
{
|
||
int current_mode[N_ENTITIES];
|
||
|
||
/* Set the anticipatable and computing arrays. */
|
||
sbitmap_vector_zero (antic, last_basic_block);
|
||
sbitmap_vector_zero (comp, last_basic_block);
|
||
for (j = n_entities - 1; j >= 0; j--)
|
||
{
|
||
int m = current_mode[j] = MODE_PRIORITY_TO_MODE (entity_map[j], i);
|
||
struct bb_info *info = bb_info[j];
|
||
|
||
FOR_EACH_BB (bb)
|
||
{
|
||
if (info[bb->index].seginfo->mode == m)
|
||
SET_BIT (antic[bb->index], j);
|
||
|
||
if (info[bb->index].computing == m)
|
||
SET_BIT (comp[bb->index], j);
|
||
}
|
||
}
|
||
|
||
/* Calculate the optimal locations for the
|
||
placement mode switches to modes with priority I. */
|
||
|
||
FOR_EACH_BB (bb)
|
||
sbitmap_not (kill[bb->index], transp[bb->index]);
|
||
edge_list = pre_edge_lcm (file, 1, transp, comp, antic,
|
||
kill, &insert, &delete);
|
||
|
||
for (j = n_entities - 1; j >= 0; j--)
|
||
{
|
||
/* Insert all mode sets that have been inserted by lcm. */
|
||
int no_mode = num_modes[entity_map[j]];
|
||
|
||
/* Wherever we have moved a mode setting upwards in the flow graph,
|
||
the blocks between the new setting site and the now redundant
|
||
computation ceases to be transparent for any lower-priority
|
||
mode of the same entity. First set the aux field of each
|
||
insertion site edge non-transparent, then propagate the new
|
||
non-transparency from the redundant computation upwards till
|
||
we hit an insertion site or an already non-transparent block. */
|
||
for (e = NUM_EDGES (edge_list) - 1; e >= 0; e--)
|
||
{
|
||
edge eg = INDEX_EDGE (edge_list, e);
|
||
int mode;
|
||
basic_block src_bb;
|
||
HARD_REG_SET live_at_edge;
|
||
rtx mode_set;
|
||
|
||
eg->aux = 0;
|
||
|
||
if (! TEST_BIT (insert[e], j))
|
||
continue;
|
||
|
||
eg->aux = (void *)1;
|
||
|
||
mode = current_mode[j];
|
||
src_bb = eg->src;
|
||
|
||
REG_SET_TO_HARD_REG_SET (live_at_edge,
|
||
src_bb->global_live_at_end);
|
||
|
||
start_sequence ();
|
||
EMIT_MODE_SET (entity_map[j], mode, live_at_edge);
|
||
mode_set = get_insns ();
|
||
end_sequence ();
|
||
|
||
/* Do not bother to insert empty sequence. */
|
||
if (mode_set == NULL_RTX)
|
||
continue;
|
||
|
||
/* If this is an abnormal edge, we'll insert at the end
|
||
of the previous block. */
|
||
if (eg->flags & EDGE_ABNORMAL)
|
||
{
|
||
emited = true;
|
||
if (GET_CODE (src_bb->end) == JUMP_INSN)
|
||
emit_insn_before (mode_set, src_bb->end);
|
||
/* It doesn't make sense to switch to normal mode
|
||
after a CALL_INSN, so we're going to abort if we
|
||
find one. The cases in which a CALL_INSN may
|
||
have an abnormal edge are sibcalls and EH edges.
|
||
In the case of sibcalls, the dest basic-block is
|
||
the EXIT_BLOCK, that runs in normal mode; it is
|
||
assumed that a sibcall insn requires normal mode
|
||
itself, so no mode switch would be required after
|
||
the call (it wouldn't make sense, anyway). In
|
||
the case of EH edges, EH entry points also start
|
||
in normal mode, so a similar reasoning applies. */
|
||
else if (GET_CODE (src_bb->end) == INSN)
|
||
emit_insn_after (mode_set, src_bb->end);
|
||
else
|
||
abort ();
|
||
bb_info[j][src_bb->index].computing = mode;
|
||
RESET_BIT (transp[src_bb->index], j);
|
||
}
|
||
else
|
||
{
|
||
need_commit = 1;
|
||
insert_insn_on_edge (mode_set, eg);
|
||
}
|
||
}
|
||
|
||
FOR_EACH_BB_REVERSE (bb)
|
||
if (TEST_BIT (delete[bb->index], j))
|
||
{
|
||
make_preds_opaque (bb, j);
|
||
/* Cancel the 'deleted' mode set. */
|
||
bb_info[j][bb->index].seginfo->mode = no_mode;
|
||
}
|
||
}
|
||
|
||
clear_aux_for_edges ();
|
||
free_edge_list (edge_list);
|
||
}
|
||
|
||
/* Now output the remaining mode sets in all the segments. */
|
||
for (j = n_entities - 1; j >= 0; j--)
|
||
{
|
||
int no_mode = num_modes[entity_map[j]];
|
||
|
||
FOR_EACH_BB_REVERSE (bb)
|
||
{
|
||
struct seginfo *ptr, *next;
|
||
for (ptr = bb_info[j][bb->index].seginfo; ptr; ptr = next)
|
||
{
|
||
next = ptr->next;
|
||
if (ptr->mode != no_mode)
|
||
{
|
||
rtx mode_set;
|
||
|
||
start_sequence ();
|
||
EMIT_MODE_SET (entity_map[j], ptr->mode, ptr->regs_live);
|
||
mode_set = get_insns ();
|
||
end_sequence ();
|
||
|
||
/* Do not bother to insert empty sequence. */
|
||
if (mode_set == NULL_RTX)
|
||
continue;
|
||
|
||
emited = true;
|
||
if (GET_CODE (ptr->insn_ptr) == NOTE
|
||
&& (NOTE_LINE_NUMBER (ptr->insn_ptr)
|
||
== NOTE_INSN_BASIC_BLOCK))
|
||
emit_insn_after (mode_set, ptr->insn_ptr);
|
||
else
|
||
emit_insn_before (mode_set, ptr->insn_ptr);
|
||
}
|
||
|
||
free (ptr);
|
||
}
|
||
}
|
||
|
||
free (bb_info[j]);
|
||
}
|
||
|
||
/* Finished. Free up all the things we've allocated. */
|
||
|
||
sbitmap_vector_free (kill);
|
||
sbitmap_vector_free (antic);
|
||
sbitmap_vector_free (transp);
|
||
sbitmap_vector_free (comp);
|
||
sbitmap_vector_free (delete);
|
||
sbitmap_vector_free (insert);
|
||
|
||
if (need_commit)
|
||
commit_edge_insertions ();
|
||
|
||
#ifdef NORMAL_MODE
|
||
cleanup_cfg (CLEANUP_NO_INSN_DEL);
|
||
#else
|
||
if (!need_commit && !emited)
|
||
return 0;
|
||
#endif
|
||
|
||
max_regno = max_reg_num ();
|
||
allocate_reg_info (max_regno, FALSE, FALSE);
|
||
update_life_info_in_dirty_blocks (UPDATE_LIFE_GLOBAL_RM_NOTES,
|
||
(PROP_DEATH_NOTES | PROP_KILL_DEAD_CODE
|
||
| PROP_SCAN_DEAD_CODE));
|
||
|
||
return 1;
|
||
}
|
||
#endif /* OPTIMIZE_MODE_SWITCHING */
|