812 lines
26 KiB
C
812 lines
26 KiB
C
/* Generic partial redundancy elimination with lazy code motion support.
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Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
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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, 51 Franklin Street, Fifth Floor, Boston, MA
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02110-1301, 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 "coretypes.h"
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#include "tm.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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#include "function.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 (sbitmap *, sbitmap *, sbitmap *, sbitmap *);
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static void compute_earliest (struct edge_list *, int, sbitmap *, sbitmap *,
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sbitmap *, sbitmap *, sbitmap *);
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static void compute_laterin (struct edge_list *, sbitmap *, sbitmap *,
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sbitmap *, sbitmap *);
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static void compute_insert_delete (struct edge_list *edge_list, sbitmap *,
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sbitmap *, sbitmap *, sbitmap *, sbitmap *);
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/* Edge based LCM routines on a reverse flowgraph. */
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static void compute_farthest (struct edge_list *, int, sbitmap *, sbitmap *,
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sbitmap*, sbitmap *, sbitmap *);
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static void compute_nearerout (struct edge_list *, sbitmap *, sbitmap *,
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sbitmap *, sbitmap *);
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static void compute_rev_insert_delete (struct edge_list *edge_list, sbitmap *,
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sbitmap *, 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 (sbitmap *antloc, sbitmap *transp, 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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edge_iterator ei;
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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 = XNEWVEC (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 - NUM_FIXED_BLOCKS];
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qlen = n_basic_blocks - NUM_FIXED_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_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
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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_EACH_EDGE (e, ei, bb->preds)
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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 (struct edge_list *edge_list, int n_exprs, sbitmap *antin,
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sbitmap *antout, sbitmap *avout, sbitmap *kill,
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sbitmap *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 (struct edge_list *edge_list, sbitmap *earliest,
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sbitmap *antloc, sbitmap *later, sbitmap *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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edge_iterator ei;
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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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= XNEWVEC (basic_block, n_basic_blocks);
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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_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs)
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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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/* 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. */
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qin = worklist;
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qend = &worklist[n_basic_blocks - NUM_FIXED_BLOCKS];
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qlen = n_basic_blocks - NUM_FIXED_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_EACH_EDGE (e, ei, bb->preds)
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sbitmap_a_and_b (laterin[bb->index], laterin[bb->index],
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later[(size_t)e->aux]);
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/* Calculate LATER for all outgoing edges. */
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FOR_EACH_EDGE (e, ei, bb->succs)
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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_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
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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 (struct edge_list *edge_list, sbitmap *antloc,
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sbitmap *later, sbitmap *laterin, sbitmap *insert,
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sbitmap *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],
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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 (int n_exprs, sbitmap *transp,
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sbitmap *avloc, sbitmap *antloc, sbitmap *kill,
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sbitmap **insert, 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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#ifdef LCM_DEBUG_INFO
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if (dump_file)
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{
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fprintf (dump_file, "Edge List:\n");
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verify_edge_list (dump_file, edge_list);
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print_edge_list (dump_file, edge_list);
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dump_sbitmap_vector (dump_file, "transp", "", transp, last_basic_block);
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dump_sbitmap_vector (dump_file, "antloc", "", antloc, last_basic_block);
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dump_sbitmap_vector (dump_file, "avloc", "", avloc, last_basic_block);
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dump_sbitmap_vector (dump_file, "kill", "", kill, last_basic_block);
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}
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#endif
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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);
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sbitmap_vector_free (avin);
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/* Compute global anticipatability. */
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antin = sbitmap_vector_alloc (last_basic_block, n_exprs);
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antout = sbitmap_vector_alloc (last_basic_block, n_exprs);
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compute_antinout_edge (antloc, transp, antin, antout);
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#ifdef LCM_DEBUG_INFO
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if (dump_file)
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{
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dump_sbitmap_vector (dump_file, "antin", "", antin, last_basic_block);
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dump_sbitmap_vector (dump_file, "antout", "", antout, last_basic_block);
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}
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#endif
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/* Compute earliestness. */
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earliest = sbitmap_vector_alloc (num_edges, n_exprs);
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compute_earliest (edge_list, n_exprs, antin, antout, avout, kill, earliest);
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#ifdef LCM_DEBUG_INFO
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if (dump_file)
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dump_sbitmap_vector (dump_file, "earliest", "", earliest, num_edges);
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#endif
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sbitmap_vector_free (antout);
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sbitmap_vector_free (antin);
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sbitmap_vector_free (avout);
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later = sbitmap_vector_alloc (num_edges, n_exprs);
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/* Allocate an extra element for the exit block in the laterin vector. */
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laterin = sbitmap_vector_alloc (last_basic_block + 1, n_exprs);
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compute_laterin (edge_list, earliest, antloc, later, laterin);
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#ifdef LCM_DEBUG_INFO
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if (dump_file)
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{
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dump_sbitmap_vector (dump_file, "laterin", "", laterin, last_basic_block + 1);
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dump_sbitmap_vector (dump_file, "later", "", later, num_edges);
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}
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#endif
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sbitmap_vector_free (earliest);
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*insert = sbitmap_vector_alloc (num_edges, n_exprs);
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*delete = sbitmap_vector_alloc (last_basic_block, n_exprs);
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compute_insert_delete (edge_list, antloc, later, laterin, *insert, *delete);
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sbitmap_vector_free (laterin);
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sbitmap_vector_free (later);
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#ifdef LCM_DEBUG_INFO
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if (dump_file)
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{
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dump_sbitmap_vector (dump_file, "pre_insert_map", "", *insert, num_edges);
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dump_sbitmap_vector (dump_file, "pre_delete_map", "", *delete,
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last_basic_block);
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}
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#endif
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return edge_list;
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}
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/* Compute the AVIN and AVOUT vectors from the AVLOC and KILL vectors.
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Return the number of passes we performed to iterate to a solution. */
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void
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compute_available (sbitmap *avloc, sbitmap *kill, sbitmap *avout,
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sbitmap *avin)
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{
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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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edge_iterator ei;
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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
|
||
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)
|
||
{
|
||
*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;
|
||
}
|
||
}
|
||
|
||
clear_aux_for_edges ();
|
||
clear_aux_for_blocks ();
|
||
free (worklist);
|
||
}
|
||
|
||
/* Compute the farthest vector for edge based lcm. */
|
||
|
||
static void
|
||
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;
|
||
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 (struct edge_list *edge_list, sbitmap *farthest,
|
||
sbitmap *st_avloc, sbitmap *nearer, sbitmap *nearerout)
|
||
{
|
||
int num_edges, i;
|
||
edge e;
|
||
basic_block *worklist, *tos, bb;
|
||
edge_iterator ei;
|
||
|
||
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 = 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)
|
||
{
|
||
*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_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;
|
||
}
|
||
}
|
||
|
||
/* 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 (struct edge_list *edge_list, sbitmap *st_avloc,
|
||
sbitmap *nearer, sbitmap *nearerout,
|
||
sbitmap *insert, sbitmap *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 (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_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 (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 (dump_file)
|
||
{
|
||
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 (dump_file)
|
||
{
|
||
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,
|
||
kill, farthest);
|
||
|
||
#ifdef LCM_DEBUG_INFO
|
||
if (dump_file)
|
||
dump_sbitmap_vector (dump_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 (dump_file)
|
||
{
|
||
dump_sbitmap_vector (dump_file, "nearerout", "", nearerout,
|
||
last_basic_block + 1);
|
||
dump_sbitmap_vector (dump_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 (dump_file)
|
||
{
|
||
dump_sbitmap_vector (dump_file, "pre_insert_map", "", *insert, num_edges);
|
||
dump_sbitmap_vector (dump_file, "pre_delete_map", "", *delete,
|
||
last_basic_block);
|
||
}
|
||
#endif
|
||
return edge_list;
|
||
}
|
||
|