3381 lines
95 KiB
C
3381 lines
95 KiB
C
/* Instruction scheduling pass.
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Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998,
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1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
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Contributed by Michael Tiemann (tiemann@cygnus.com) Enhanced by,
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and currently maintained by, Jim Wilson (wilson@cygnus.com)
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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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/* This pass implements list scheduling within basic blocks. It is
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run twice: (1) after flow analysis, but before register allocation,
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and (2) after register allocation.
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The first run performs interblock scheduling, moving insns between
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different blocks in the same "region", and the second runs only
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basic block scheduling.
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Interblock motions performed are useful motions and speculative
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motions, including speculative loads. Motions requiring code
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duplication are not supported. The identification of motion type
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and the check for validity of speculative motions requires
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construction and analysis of the function's control flow graph.
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The main entry point for this pass is schedule_insns(), called for
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each function. The work of the scheduler is organized in three
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levels: (1) function level: insns are subject to splitting,
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control-flow-graph is constructed, regions are computed (after
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reload, each region is of one block), (2) region level: control
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flow graph attributes required for interblock scheduling are
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computed (dominators, reachability, etc.), data dependences and
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priorities are computed, and (3) block level: insns in the block
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are actually scheduled. */
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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 "toplev.h"
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#include "rtl.h"
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#include "tm_p.h"
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#include "hard-reg-set.h"
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#include "regs.h"
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#include "function.h"
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#include "flags.h"
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#include "insn-config.h"
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#include "insn-attr.h"
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#include "except.h"
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#include "toplev.h"
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#include "recog.h"
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#include "cfglayout.h"
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#include "params.h"
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#include "sched-int.h"
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#include "target.h"
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#include "timevar.h"
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#include "tree-pass.h"
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/* Define when we want to do count REG_DEAD notes before and after scheduling
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for sanity checking. We can't do that when conditional execution is used,
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as REG_DEAD exist only for unconditional deaths. */
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#if !defined (HAVE_conditional_execution) && defined (ENABLE_CHECKING)
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#define CHECK_DEAD_NOTES 1
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#else
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#define CHECK_DEAD_NOTES 0
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#endif
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#ifdef INSN_SCHEDULING
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/* Some accessor macros for h_i_d members only used within this file. */
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#define INSN_REF_COUNT(INSN) (h_i_d[INSN_UID (INSN)].ref_count)
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#define FED_BY_SPEC_LOAD(insn) (h_i_d[INSN_UID (insn)].fed_by_spec_load)
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#define IS_LOAD_INSN(insn) (h_i_d[INSN_UID (insn)].is_load_insn)
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/* nr_inter/spec counts interblock/speculative motion for the function. */
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static int nr_inter, nr_spec;
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static int is_cfg_nonregular (void);
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static bool sched_is_disabled_for_current_region_p (void);
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/* A region is the main entity for interblock scheduling: insns
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are allowed to move between blocks in the same region, along
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control flow graph edges, in the 'up' direction. */
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typedef struct
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{
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/* Number of extended basic blocks in region. */
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int rgn_nr_blocks;
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/* cblocks in the region (actually index in rgn_bb_table). */
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int rgn_blocks;
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/* Dependencies for this region are already computed. Basically, indicates,
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that this is a recovery block. */
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unsigned int dont_calc_deps : 1;
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/* This region has at least one non-trivial ebb. */
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unsigned int has_real_ebb : 1;
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}
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region;
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/* Number of regions in the procedure. */
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static int nr_regions;
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/* Table of region descriptions. */
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static region *rgn_table;
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/* Array of lists of regions' blocks. */
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static int *rgn_bb_table;
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/* Topological order of blocks in the region (if b2 is reachable from
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b1, block_to_bb[b2] > block_to_bb[b1]). Note: A basic block is
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always referred to by either block or b, while its topological
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order name (in the region) is referred to by bb. */
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static int *block_to_bb;
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/* The number of the region containing a block. */
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static int *containing_rgn;
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/* The minimum probability of reaching a source block so that it will be
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considered for speculative scheduling. */
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static int min_spec_prob;
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#define RGN_NR_BLOCKS(rgn) (rgn_table[rgn].rgn_nr_blocks)
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#define RGN_BLOCKS(rgn) (rgn_table[rgn].rgn_blocks)
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#define RGN_DONT_CALC_DEPS(rgn) (rgn_table[rgn].dont_calc_deps)
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#define RGN_HAS_REAL_EBB(rgn) (rgn_table[rgn].has_real_ebb)
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#define BLOCK_TO_BB(block) (block_to_bb[block])
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#define CONTAINING_RGN(block) (containing_rgn[block])
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void debug_regions (void);
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static void find_single_block_region (void);
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static void find_rgns (void);
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static void extend_rgns (int *, int *, sbitmap, int *);
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static bool too_large (int, int *, int *);
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extern void debug_live (int, int);
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/* Blocks of the current region being scheduled. */
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static int current_nr_blocks;
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static int current_blocks;
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static int rgn_n_insns;
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/* The mapping from ebb to block. */
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/* ebb_head [i] - is index in rgn_bb_table, while
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EBB_HEAD (i) - is basic block index.
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BASIC_BLOCK (EBB_HEAD (i)) - head of ebb. */
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#define BB_TO_BLOCK(ebb) (rgn_bb_table[ebb_head[ebb]])
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#define EBB_FIRST_BB(ebb) BASIC_BLOCK (BB_TO_BLOCK (ebb))
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#define EBB_LAST_BB(ebb) BASIC_BLOCK (rgn_bb_table[ebb_head[ebb + 1] - 1])
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/* Target info declarations.
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The block currently being scheduled is referred to as the "target" block,
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while other blocks in the region from which insns can be moved to the
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target are called "source" blocks. The candidate structure holds info
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about such sources: are they valid? Speculative? Etc. */
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typedef struct
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{
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basic_block *first_member;
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int nr_members;
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}
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bblst;
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typedef struct
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{
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char is_valid;
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char is_speculative;
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int src_prob;
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bblst split_bbs;
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bblst update_bbs;
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}
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candidate;
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static candidate *candidate_table;
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/* A speculative motion requires checking live information on the path
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from 'source' to 'target'. The split blocks are those to be checked.
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After a speculative motion, live information should be modified in
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the 'update' blocks.
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Lists of split and update blocks for each candidate of the current
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target are in array bblst_table. */
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static basic_block *bblst_table;
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static int bblst_size, bblst_last;
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#define IS_VALID(src) ( candidate_table[src].is_valid )
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#define IS_SPECULATIVE(src) ( candidate_table[src].is_speculative )
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#define SRC_PROB(src) ( candidate_table[src].src_prob )
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/* The bb being currently scheduled. */
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static int target_bb;
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/* List of edges. */
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typedef struct
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{
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edge *first_member;
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int nr_members;
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}
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edgelst;
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static edge *edgelst_table;
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static int edgelst_last;
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static void extract_edgelst (sbitmap, edgelst *);
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/* Target info functions. */
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static void split_edges (int, int, edgelst *);
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static void compute_trg_info (int);
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void debug_candidate (int);
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void debug_candidates (int);
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/* Dominators array: dom[i] contains the sbitmap of dominators of
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bb i in the region. */
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static sbitmap *dom;
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/* bb 0 is the only region entry. */
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#define IS_RGN_ENTRY(bb) (!bb)
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/* Is bb_src dominated by bb_trg. */
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#define IS_DOMINATED(bb_src, bb_trg) \
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( TEST_BIT (dom[bb_src], bb_trg) )
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/* Probability: Prob[i] is an int in [0, REG_BR_PROB_BASE] which is
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the probability of bb i relative to the region entry. */
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static int *prob;
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/* Bit-set of edges, where bit i stands for edge i. */
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typedef sbitmap edgeset;
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/* Number of edges in the region. */
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static int rgn_nr_edges;
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/* Array of size rgn_nr_edges. */
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static edge *rgn_edges;
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/* Mapping from each edge in the graph to its number in the rgn. */
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#define EDGE_TO_BIT(edge) ((int)(size_t)(edge)->aux)
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#define SET_EDGE_TO_BIT(edge,nr) ((edge)->aux = (void *)(size_t)(nr))
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/* The split edges of a source bb is different for each target
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bb. In order to compute this efficiently, the 'potential-split edges'
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are computed for each bb prior to scheduling a region. This is actually
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the split edges of each bb relative to the region entry.
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pot_split[bb] is the set of potential split edges of bb. */
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static edgeset *pot_split;
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/* For every bb, a set of its ancestor edges. */
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static edgeset *ancestor_edges;
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/* Array of EBBs sizes. Currently we can get a ebb only through
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splitting of currently scheduling block, therefore, we don't need
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ebb_head array for every region, its sufficient to hold it only
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for current one. */
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static int *ebb_head;
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static void compute_dom_prob_ps (int);
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#define INSN_PROBABILITY(INSN) (SRC_PROB (BLOCK_TO_BB (BLOCK_NUM (INSN))))
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#define IS_SPECULATIVE_INSN(INSN) (IS_SPECULATIVE (BLOCK_TO_BB (BLOCK_NUM (INSN))))
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#define INSN_BB(INSN) (BLOCK_TO_BB (BLOCK_NUM (INSN)))
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/* Speculative scheduling functions. */
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static int check_live_1 (int, rtx);
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static void update_live_1 (int, rtx);
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static int check_live (rtx, int);
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static void update_live (rtx, int);
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static void set_spec_fed (rtx);
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static int is_pfree (rtx, int, int);
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static int find_conditional_protection (rtx, int);
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static int is_conditionally_protected (rtx, int, int);
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static int is_prisky (rtx, int, int);
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static int is_exception_free (rtx, int, int);
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static bool sets_likely_spilled (rtx);
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static void sets_likely_spilled_1 (rtx, rtx, void *);
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static void add_branch_dependences (rtx, rtx);
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static void compute_block_backward_dependences (int);
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void debug_dependencies (void);
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static void init_regions (void);
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static void schedule_region (int);
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static rtx concat_INSN_LIST (rtx, rtx);
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static void concat_insn_mem_list (rtx, rtx, rtx *, rtx *);
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static void propagate_deps (int, struct deps *);
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static void free_pending_lists (void);
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/* Functions for construction of the control flow graph. */
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/* Return 1 if control flow graph should not be constructed, 0 otherwise.
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We decide not to build the control flow graph if there is possibly more
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than one entry to the function, if computed branches exist, if we
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have nonlocal gotos, or if we have an unreachable loop. */
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static int
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is_cfg_nonregular (void)
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{
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basic_block b;
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rtx insn;
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/* If we have a label that could be the target of a nonlocal goto, then
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the cfg is not well structured. */
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if (nonlocal_goto_handler_labels)
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return 1;
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/* If we have any forced labels, then the cfg is not well structured. */
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if (forced_labels)
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return 1;
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/* If we have exception handlers, then we consider the cfg not well
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structured. ?!? We should be able to handle this now that flow.c
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computes an accurate cfg for EH. */
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if (current_function_has_exception_handlers ())
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return 1;
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/* If we have non-jumping insns which refer to labels, then we consider
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the cfg not well structured. */
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FOR_EACH_BB (b)
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FOR_BB_INSNS (b, insn)
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{
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/* Check for labels referred by non-jump insns. */
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if (NONJUMP_INSN_P (insn) || CALL_P (insn))
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{
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rtx note = find_reg_note (insn, REG_LABEL, NULL_RTX);
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if (note
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&& ! (JUMP_P (NEXT_INSN (insn))
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&& find_reg_note (NEXT_INSN (insn), REG_LABEL,
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XEXP (note, 0))))
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return 1;
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}
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/* If this function has a computed jump, then we consider the cfg
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not well structured. */
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else if (JUMP_P (insn) && computed_jump_p (insn))
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return 1;
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}
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/* Unreachable loops with more than one basic block are detected
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during the DFS traversal in find_rgns.
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Unreachable loops with a single block are detected here. This
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test is redundant with the one in find_rgns, but it's much
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cheaper to go ahead and catch the trivial case here. */
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FOR_EACH_BB (b)
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{
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if (EDGE_COUNT (b->preds) == 0
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|| (single_pred_p (b)
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&& single_pred (b) == b))
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return 1;
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}
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/* All the tests passed. Consider the cfg well structured. */
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return 0;
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}
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/* Extract list of edges from a bitmap containing EDGE_TO_BIT bits. */
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static void
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extract_edgelst (sbitmap set, edgelst *el)
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{
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unsigned int i = 0;
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sbitmap_iterator sbi;
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/* edgelst table space is reused in each call to extract_edgelst. */
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edgelst_last = 0;
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el->first_member = &edgelst_table[edgelst_last];
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el->nr_members = 0;
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/* Iterate over each word in the bitset. */
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EXECUTE_IF_SET_IN_SBITMAP (set, 0, i, sbi)
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{
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edgelst_table[edgelst_last++] = rgn_edges[i];
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el->nr_members++;
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}
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}
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||
|
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/* Functions for the construction of regions. */
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/* Print the regions, for debugging purposes. Callable from debugger. */
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void
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debug_regions (void)
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{
|
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int rgn, bb;
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fprintf (sched_dump, "\n;; ------------ REGIONS ----------\n\n");
|
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for (rgn = 0; rgn < nr_regions; rgn++)
|
||
{
|
||
fprintf (sched_dump, ";;\trgn %d nr_blocks %d:\n", rgn,
|
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rgn_table[rgn].rgn_nr_blocks);
|
||
fprintf (sched_dump, ";;\tbb/block: ");
|
||
|
||
/* We don't have ebb_head initialized yet, so we can't use
|
||
BB_TO_BLOCK (). */
|
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current_blocks = RGN_BLOCKS (rgn);
|
||
|
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for (bb = 0; bb < rgn_table[rgn].rgn_nr_blocks; bb++)
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fprintf (sched_dump, " %d/%d ", bb, rgn_bb_table[current_blocks + bb]);
|
||
|
||
fprintf (sched_dump, "\n\n");
|
||
}
|
||
}
|
||
|
||
/* Build a single block region for each basic block in the function.
|
||
This allows for using the same code for interblock and basic block
|
||
scheduling. */
|
||
|
||
static void
|
||
find_single_block_region (void)
|
||
{
|
||
basic_block bb;
|
||
|
||
nr_regions = 0;
|
||
|
||
FOR_EACH_BB (bb)
|
||
{
|
||
rgn_bb_table[nr_regions] = bb->index;
|
||
RGN_NR_BLOCKS (nr_regions) = 1;
|
||
RGN_BLOCKS (nr_regions) = nr_regions;
|
||
RGN_DONT_CALC_DEPS (nr_regions) = 0;
|
||
RGN_HAS_REAL_EBB (nr_regions) = 0;
|
||
CONTAINING_RGN (bb->index) = nr_regions;
|
||
BLOCK_TO_BB (bb->index) = 0;
|
||
nr_regions++;
|
||
}
|
||
}
|
||
|
||
/* Update number of blocks and the estimate for number of insns
|
||
in the region. Return true if the region is "too large" for interblock
|
||
scheduling (compile time considerations). */
|
||
|
||
static bool
|
||
too_large (int block, int *num_bbs, int *num_insns)
|
||
{
|
||
(*num_bbs)++;
|
||
(*num_insns) += (INSN_LUID (BB_END (BASIC_BLOCK (block)))
|
||
- INSN_LUID (BB_HEAD (BASIC_BLOCK (block))));
|
||
|
||
return ((*num_bbs > PARAM_VALUE (PARAM_MAX_SCHED_REGION_BLOCKS))
|
||
|| (*num_insns > PARAM_VALUE (PARAM_MAX_SCHED_REGION_INSNS)));
|
||
}
|
||
|
||
/* Update_loop_relations(blk, hdr): Check if the loop headed by max_hdr[blk]
|
||
is still an inner loop. Put in max_hdr[blk] the header of the most inner
|
||
loop containing blk. */
|
||
#define UPDATE_LOOP_RELATIONS(blk, hdr) \
|
||
{ \
|
||
if (max_hdr[blk] == -1) \
|
||
max_hdr[blk] = hdr; \
|
||
else if (dfs_nr[max_hdr[blk]] > dfs_nr[hdr]) \
|
||
RESET_BIT (inner, hdr); \
|
||
else if (dfs_nr[max_hdr[blk]] < dfs_nr[hdr]) \
|
||
{ \
|
||
RESET_BIT (inner,max_hdr[blk]); \
|
||
max_hdr[blk] = hdr; \
|
||
} \
|
||
}
|
||
|
||
/* Find regions for interblock scheduling.
|
||
|
||
A region for scheduling can be:
|
||
|
||
* A loop-free procedure, or
|
||
|
||
* A reducible inner loop, or
|
||
|
||
* A basic block not contained in any other region.
|
||
|
||
?!? In theory we could build other regions based on extended basic
|
||
blocks or reverse extended basic blocks. Is it worth the trouble?
|
||
|
||
Loop blocks that form a region are put into the region's block list
|
||
in topological order.
|
||
|
||
This procedure stores its results into the following global (ick) variables
|
||
|
||
* rgn_nr
|
||
* rgn_table
|
||
* rgn_bb_table
|
||
* block_to_bb
|
||
* containing region
|
||
|
||
We use dominator relationships to avoid making regions out of non-reducible
|
||
loops.
|
||
|
||
This procedure needs to be converted to work on pred/succ lists instead
|
||
of edge tables. That would simplify it somewhat. */
|
||
|
||
static void
|
||
find_rgns (void)
|
||
{
|
||
int *max_hdr, *dfs_nr, *degree;
|
||
char no_loops = 1;
|
||
int node, child, loop_head, i, head, tail;
|
||
int count = 0, sp, idx = 0;
|
||
edge_iterator current_edge;
|
||
edge_iterator *stack;
|
||
int num_bbs, num_insns, unreachable;
|
||
int too_large_failure;
|
||
basic_block bb;
|
||
|
||
/* Note if a block is a natural loop header. */
|
||
sbitmap header;
|
||
|
||
/* Note if a block is a natural inner loop header. */
|
||
sbitmap inner;
|
||
|
||
/* Note if a block is in the block queue. */
|
||
sbitmap in_queue;
|
||
|
||
/* Note if a block is in the block queue. */
|
||
sbitmap in_stack;
|
||
|
||
/* Perform a DFS traversal of the cfg. Identify loop headers, inner loops
|
||
and a mapping from block to its loop header (if the block is contained
|
||
in a loop, else -1).
|
||
|
||
Store results in HEADER, INNER, and MAX_HDR respectively, these will
|
||
be used as inputs to the second traversal.
|
||
|
||
STACK, SP and DFS_NR are only used during the first traversal. */
|
||
|
||
/* Allocate and initialize variables for the first traversal. */
|
||
max_hdr = XNEWVEC (int, last_basic_block);
|
||
dfs_nr = XCNEWVEC (int, last_basic_block);
|
||
stack = XNEWVEC (edge_iterator, n_edges);
|
||
|
||
inner = sbitmap_alloc (last_basic_block);
|
||
sbitmap_ones (inner);
|
||
|
||
header = sbitmap_alloc (last_basic_block);
|
||
sbitmap_zero (header);
|
||
|
||
in_queue = sbitmap_alloc (last_basic_block);
|
||
sbitmap_zero (in_queue);
|
||
|
||
in_stack = sbitmap_alloc (last_basic_block);
|
||
sbitmap_zero (in_stack);
|
||
|
||
for (i = 0; i < last_basic_block; i++)
|
||
max_hdr[i] = -1;
|
||
|
||
#define EDGE_PASSED(E) (ei_end_p ((E)) || ei_edge ((E))->aux)
|
||
#define SET_EDGE_PASSED(E) (ei_edge ((E))->aux = ei_edge ((E)))
|
||
|
||
/* DFS traversal to find inner loops in the cfg. */
|
||
|
||
current_edge = ei_start (single_succ (ENTRY_BLOCK_PTR)->succs);
|
||
sp = -1;
|
||
|
||
while (1)
|
||
{
|
||
if (EDGE_PASSED (current_edge))
|
||
{
|
||
/* We have reached a leaf node or a node that was already
|
||
processed. Pop edges off the stack until we find
|
||
an edge that has not yet been processed. */
|
||
while (sp >= 0 && EDGE_PASSED (current_edge))
|
||
{
|
||
/* Pop entry off the stack. */
|
||
current_edge = stack[sp--];
|
||
node = ei_edge (current_edge)->src->index;
|
||
gcc_assert (node != ENTRY_BLOCK);
|
||
child = ei_edge (current_edge)->dest->index;
|
||
gcc_assert (child != EXIT_BLOCK);
|
||
RESET_BIT (in_stack, child);
|
||
if (max_hdr[child] >= 0 && TEST_BIT (in_stack, max_hdr[child]))
|
||
UPDATE_LOOP_RELATIONS (node, max_hdr[child]);
|
||
ei_next (¤t_edge);
|
||
}
|
||
|
||
/* See if have finished the DFS tree traversal. */
|
||
if (sp < 0 && EDGE_PASSED (current_edge))
|
||
break;
|
||
|
||
/* Nope, continue the traversal with the popped node. */
|
||
continue;
|
||
}
|
||
|
||
/* Process a node. */
|
||
node = ei_edge (current_edge)->src->index;
|
||
gcc_assert (node != ENTRY_BLOCK);
|
||
SET_BIT (in_stack, node);
|
||
dfs_nr[node] = ++count;
|
||
|
||
/* We don't traverse to the exit block. */
|
||
child = ei_edge (current_edge)->dest->index;
|
||
if (child == EXIT_BLOCK)
|
||
{
|
||
SET_EDGE_PASSED (current_edge);
|
||
ei_next (¤t_edge);
|
||
continue;
|
||
}
|
||
|
||
/* If the successor is in the stack, then we've found a loop.
|
||
Mark the loop, if it is not a natural loop, then it will
|
||
be rejected during the second traversal. */
|
||
if (TEST_BIT (in_stack, child))
|
||
{
|
||
no_loops = 0;
|
||
SET_BIT (header, child);
|
||
UPDATE_LOOP_RELATIONS (node, child);
|
||
SET_EDGE_PASSED (current_edge);
|
||
ei_next (¤t_edge);
|
||
continue;
|
||
}
|
||
|
||
/* If the child was already visited, then there is no need to visit
|
||
it again. Just update the loop relationships and restart
|
||
with a new edge. */
|
||
if (dfs_nr[child])
|
||
{
|
||
if (max_hdr[child] >= 0 && TEST_BIT (in_stack, max_hdr[child]))
|
||
UPDATE_LOOP_RELATIONS (node, max_hdr[child]);
|
||
SET_EDGE_PASSED (current_edge);
|
||
ei_next (¤t_edge);
|
||
continue;
|
||
}
|
||
|
||
/* Push an entry on the stack and continue DFS traversal. */
|
||
stack[++sp] = current_edge;
|
||
SET_EDGE_PASSED (current_edge);
|
||
current_edge = ei_start (ei_edge (current_edge)->dest->succs);
|
||
}
|
||
|
||
/* Reset ->aux field used by EDGE_PASSED. */
|
||
FOR_ALL_BB (bb)
|
||
{
|
||
edge_iterator ei;
|
||
edge e;
|
||
FOR_EACH_EDGE (e, ei, bb->succs)
|
||
e->aux = NULL;
|
||
}
|
||
|
||
|
||
/* Another check for unreachable blocks. The earlier test in
|
||
is_cfg_nonregular only finds unreachable blocks that do not
|
||
form a loop.
|
||
|
||
The DFS traversal will mark every block that is reachable from
|
||
the entry node by placing a nonzero value in dfs_nr. Thus if
|
||
dfs_nr is zero for any block, then it must be unreachable. */
|
||
unreachable = 0;
|
||
FOR_EACH_BB (bb)
|
||
if (dfs_nr[bb->index] == 0)
|
||
{
|
||
unreachable = 1;
|
||
break;
|
||
}
|
||
|
||
/* Gross. To avoid wasting memory, the second pass uses the dfs_nr array
|
||
to hold degree counts. */
|
||
degree = dfs_nr;
|
||
|
||
FOR_EACH_BB (bb)
|
||
degree[bb->index] = EDGE_COUNT (bb->preds);
|
||
|
||
/* Do not perform region scheduling if there are any unreachable
|
||
blocks. */
|
||
if (!unreachable)
|
||
{
|
||
int *queue, *degree1 = NULL;
|
||
/* We use EXTENDED_RGN_HEADER as an addition to HEADER and put
|
||
there basic blocks, which are forced to be region heads.
|
||
This is done to try to assemble few smaller regions
|
||
from a too_large region. */
|
||
sbitmap extended_rgn_header = NULL;
|
||
bool extend_regions_p;
|
||
|
||
if (no_loops)
|
||
SET_BIT (header, 0);
|
||
|
||
/* Second traversal:find reducible inner loops and topologically sort
|
||
block of each region. */
|
||
|
||
queue = XNEWVEC (int, n_basic_blocks);
|
||
|
||
extend_regions_p = PARAM_VALUE (PARAM_MAX_SCHED_EXTEND_REGIONS_ITERS) > 0;
|
||
if (extend_regions_p)
|
||
{
|
||
degree1 = xmalloc (last_basic_block * sizeof (int));
|
||
extended_rgn_header = sbitmap_alloc (last_basic_block);
|
||
sbitmap_zero (extended_rgn_header);
|
||
}
|
||
|
||
/* Find blocks which are inner loop headers. We still have non-reducible
|
||
loops to consider at this point. */
|
||
FOR_EACH_BB (bb)
|
||
{
|
||
if (TEST_BIT (header, bb->index) && TEST_BIT (inner, bb->index))
|
||
{
|
||
edge e;
|
||
edge_iterator ei;
|
||
basic_block jbb;
|
||
|
||
/* Now check that the loop is reducible. We do this separate
|
||
from finding inner loops so that we do not find a reducible
|
||
loop which contains an inner non-reducible loop.
|
||
|
||
A simple way to find reducible/natural loops is to verify
|
||
that each block in the loop is dominated by the loop
|
||
header.
|
||
|
||
If there exists a block that is not dominated by the loop
|
||
header, then the block is reachable from outside the loop
|
||
and thus the loop is not a natural loop. */
|
||
FOR_EACH_BB (jbb)
|
||
{
|
||
/* First identify blocks in the loop, except for the loop
|
||
entry block. */
|
||
if (bb->index == max_hdr[jbb->index] && bb != jbb)
|
||
{
|
||
/* Now verify that the block is dominated by the loop
|
||
header. */
|
||
if (!dominated_by_p (CDI_DOMINATORS, jbb, bb))
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* If we exited the loop early, then I is the header of
|
||
a non-reducible loop and we should quit processing it
|
||
now. */
|
||
if (jbb != EXIT_BLOCK_PTR)
|
||
continue;
|
||
|
||
/* I is a header of an inner loop, or block 0 in a subroutine
|
||
with no loops at all. */
|
||
head = tail = -1;
|
||
too_large_failure = 0;
|
||
loop_head = max_hdr[bb->index];
|
||
|
||
if (extend_regions_p)
|
||
/* We save degree in case when we meet a too_large region
|
||
and cancel it. We need a correct degree later when
|
||
calling extend_rgns. */
|
||
memcpy (degree1, degree, last_basic_block * sizeof (int));
|
||
|
||
/* Decrease degree of all I's successors for topological
|
||
ordering. */
|
||
FOR_EACH_EDGE (e, ei, bb->succs)
|
||
if (e->dest != EXIT_BLOCK_PTR)
|
||
--degree[e->dest->index];
|
||
|
||
/* Estimate # insns, and count # blocks in the region. */
|
||
num_bbs = 1;
|
||
num_insns = (INSN_LUID (BB_END (bb))
|
||
- INSN_LUID (BB_HEAD (bb)));
|
||
|
||
/* Find all loop latches (blocks with back edges to the loop
|
||
header) or all the leaf blocks in the cfg has no loops.
|
||
|
||
Place those blocks into the queue. */
|
||
if (no_loops)
|
||
{
|
||
FOR_EACH_BB (jbb)
|
||
/* Leaf nodes have only a single successor which must
|
||
be EXIT_BLOCK. */
|
||
if (single_succ_p (jbb)
|
||
&& single_succ (jbb) == EXIT_BLOCK_PTR)
|
||
{
|
||
queue[++tail] = jbb->index;
|
||
SET_BIT (in_queue, jbb->index);
|
||
|
||
if (too_large (jbb->index, &num_bbs, &num_insns))
|
||
{
|
||
too_large_failure = 1;
|
||
break;
|
||
}
|
||
}
|
||
}
|
||
else
|
||
{
|
||
edge e;
|
||
|
||
FOR_EACH_EDGE (e, ei, bb->preds)
|
||
{
|
||
if (e->src == ENTRY_BLOCK_PTR)
|
||
continue;
|
||
|
||
node = e->src->index;
|
||
|
||
if (max_hdr[node] == loop_head && node != bb->index)
|
||
{
|
||
/* This is a loop latch. */
|
||
queue[++tail] = node;
|
||
SET_BIT (in_queue, node);
|
||
|
||
if (too_large (node, &num_bbs, &num_insns))
|
||
{
|
||
too_large_failure = 1;
|
||
break;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Now add all the blocks in the loop to the queue.
|
||
|
||
We know the loop is a natural loop; however the algorithm
|
||
above will not always mark certain blocks as being in the
|
||
loop. Consider:
|
||
node children
|
||
a b,c
|
||
b c
|
||
c a,d
|
||
d b
|
||
|
||
The algorithm in the DFS traversal may not mark B & D as part
|
||
of the loop (i.e. they will not have max_hdr set to A).
|
||
|
||
We know they can not be loop latches (else they would have
|
||
had max_hdr set since they'd have a backedge to a dominator
|
||
block). So we don't need them on the initial queue.
|
||
|
||
We know they are part of the loop because they are dominated
|
||
by the loop header and can be reached by a backwards walk of
|
||
the edges starting with nodes on the initial queue.
|
||
|
||
It is safe and desirable to include those nodes in the
|
||
loop/scheduling region. To do so we would need to decrease
|
||
the degree of a node if it is the target of a backedge
|
||
within the loop itself as the node is placed in the queue.
|
||
|
||
We do not do this because I'm not sure that the actual
|
||
scheduling code will properly handle this case. ?!? */
|
||
|
||
while (head < tail && !too_large_failure)
|
||
{
|
||
edge e;
|
||
child = queue[++head];
|
||
|
||
FOR_EACH_EDGE (e, ei, BASIC_BLOCK (child)->preds)
|
||
{
|
||
node = e->src->index;
|
||
|
||
/* See discussion above about nodes not marked as in
|
||
this loop during the initial DFS traversal. */
|
||
if (e->src == ENTRY_BLOCK_PTR
|
||
|| max_hdr[node] != loop_head)
|
||
{
|
||
tail = -1;
|
||
break;
|
||
}
|
||
else if (!TEST_BIT (in_queue, node) && node != bb->index)
|
||
{
|
||
queue[++tail] = node;
|
||
SET_BIT (in_queue, node);
|
||
|
||
if (too_large (node, &num_bbs, &num_insns))
|
||
{
|
||
too_large_failure = 1;
|
||
break;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
if (tail >= 0 && !too_large_failure)
|
||
{
|
||
/* Place the loop header into list of region blocks. */
|
||
degree[bb->index] = -1;
|
||
rgn_bb_table[idx] = bb->index;
|
||
RGN_NR_BLOCKS (nr_regions) = num_bbs;
|
||
RGN_BLOCKS (nr_regions) = idx++;
|
||
RGN_DONT_CALC_DEPS (nr_regions) = 0;
|
||
RGN_HAS_REAL_EBB (nr_regions) = 0;
|
||
CONTAINING_RGN (bb->index) = nr_regions;
|
||
BLOCK_TO_BB (bb->index) = count = 0;
|
||
|
||
/* Remove blocks from queue[] when their in degree
|
||
becomes zero. Repeat until no blocks are left on the
|
||
list. This produces a topological list of blocks in
|
||
the region. */
|
||
while (tail >= 0)
|
||
{
|
||
if (head < 0)
|
||
head = tail;
|
||
child = queue[head];
|
||
if (degree[child] == 0)
|
||
{
|
||
edge e;
|
||
|
||
degree[child] = -1;
|
||
rgn_bb_table[idx++] = child;
|
||
BLOCK_TO_BB (child) = ++count;
|
||
CONTAINING_RGN (child) = nr_regions;
|
||
queue[head] = queue[tail--];
|
||
|
||
FOR_EACH_EDGE (e, ei, BASIC_BLOCK (child)->succs)
|
||
if (e->dest != EXIT_BLOCK_PTR)
|
||
--degree[e->dest->index];
|
||
}
|
||
else
|
||
--head;
|
||
}
|
||
++nr_regions;
|
||
}
|
||
else if (extend_regions_p)
|
||
{
|
||
/* Restore DEGREE. */
|
||
int *t = degree;
|
||
|
||
degree = degree1;
|
||
degree1 = t;
|
||
|
||
/* And force successors of BB to be region heads.
|
||
This may provide several smaller regions instead
|
||
of one too_large region. */
|
||
FOR_EACH_EDGE (e, ei, bb->succs)
|
||
if (e->dest != EXIT_BLOCK_PTR)
|
||
SET_BIT (extended_rgn_header, e->dest->index);
|
||
}
|
||
}
|
||
}
|
||
free (queue);
|
||
|
||
if (extend_regions_p)
|
||
{
|
||
free (degree1);
|
||
|
||
sbitmap_a_or_b (header, header, extended_rgn_header);
|
||
sbitmap_free (extended_rgn_header);
|
||
|
||
extend_rgns (degree, &idx, header, max_hdr);
|
||
}
|
||
}
|
||
|
||
/* Any block that did not end up in a region is placed into a region
|
||
by itself. */
|
||
FOR_EACH_BB (bb)
|
||
if (degree[bb->index] >= 0)
|
||
{
|
||
rgn_bb_table[idx] = bb->index;
|
||
RGN_NR_BLOCKS (nr_regions) = 1;
|
||
RGN_BLOCKS (nr_regions) = idx++;
|
||
RGN_DONT_CALC_DEPS (nr_regions) = 0;
|
||
RGN_HAS_REAL_EBB (nr_regions) = 0;
|
||
CONTAINING_RGN (bb->index) = nr_regions++;
|
||
BLOCK_TO_BB (bb->index) = 0;
|
||
}
|
||
|
||
free (max_hdr);
|
||
free (degree);
|
||
free (stack);
|
||
sbitmap_free (header);
|
||
sbitmap_free (inner);
|
||
sbitmap_free (in_queue);
|
||
sbitmap_free (in_stack);
|
||
}
|
||
|
||
static int gather_region_statistics (int **);
|
||
static void print_region_statistics (int *, int, int *, int);
|
||
|
||
/* Calculate the histogram that shows the number of regions having the
|
||
given number of basic blocks, and store it in the RSP array. Return
|
||
the size of this array. */
|
||
static int
|
||
gather_region_statistics (int **rsp)
|
||
{
|
||
int i, *a = 0, a_sz = 0;
|
||
|
||
/* a[i] is the number of regions that have (i + 1) basic blocks. */
|
||
for (i = 0; i < nr_regions; i++)
|
||
{
|
||
int nr_blocks = RGN_NR_BLOCKS (i);
|
||
|
||
gcc_assert (nr_blocks >= 1);
|
||
|
||
if (nr_blocks > a_sz)
|
||
{
|
||
a = xrealloc (a, nr_blocks * sizeof (*a));
|
||
do
|
||
a[a_sz++] = 0;
|
||
while (a_sz != nr_blocks);
|
||
}
|
||
|
||
a[nr_blocks - 1]++;
|
||
}
|
||
|
||
*rsp = a;
|
||
return a_sz;
|
||
}
|
||
|
||
/* Print regions statistics. S1 and S2 denote the data before and after
|
||
calling extend_rgns, respectively. */
|
||
static void
|
||
print_region_statistics (int *s1, int s1_sz, int *s2, int s2_sz)
|
||
{
|
||
int i;
|
||
|
||
/* We iterate until s2_sz because extend_rgns does not decrease
|
||
the maximal region size. */
|
||
for (i = 1; i < s2_sz; i++)
|
||
{
|
||
int n1, n2;
|
||
|
||
n2 = s2[i];
|
||
|
||
if (n2 == 0)
|
||
continue;
|
||
|
||
if (i >= s1_sz)
|
||
n1 = 0;
|
||
else
|
||
n1 = s1[i];
|
||
|
||
fprintf (sched_dump, ";; Region extension statistics: size %d: " \
|
||
"was %d + %d more\n", i + 1, n1, n2 - n1);
|
||
}
|
||
}
|
||
|
||
/* Extend regions.
|
||
DEGREE - Array of incoming edge count, considering only
|
||
the edges, that don't have their sources in formed regions yet.
|
||
IDXP - pointer to the next available index in rgn_bb_table.
|
||
HEADER - set of all region heads.
|
||
LOOP_HDR - mapping from block to the containing loop
|
||
(two blocks can reside within one region if they have
|
||
the same loop header). */
|
||
static void
|
||
extend_rgns (int *degree, int *idxp, sbitmap header, int *loop_hdr)
|
||
{
|
||
int *order, i, rescan = 0, idx = *idxp, iter = 0, max_iter, *max_hdr;
|
||
int nblocks = n_basic_blocks - NUM_FIXED_BLOCKS;
|
||
|
||
max_iter = PARAM_VALUE (PARAM_MAX_SCHED_EXTEND_REGIONS_ITERS);
|
||
|
||
max_hdr = xmalloc (last_basic_block * sizeof (*max_hdr));
|
||
|
||
order = xmalloc (last_basic_block * sizeof (*order));
|
||
post_order_compute (order, false);
|
||
|
||
for (i = nblocks - 1; i >= 0; i--)
|
||
{
|
||
int bbn = order[i];
|
||
if (degree[bbn] >= 0)
|
||
{
|
||
max_hdr[bbn] = bbn;
|
||
rescan = 1;
|
||
}
|
||
else
|
||
/* This block already was processed in find_rgns. */
|
||
max_hdr[bbn] = -1;
|
||
}
|
||
|
||
/* The idea is to topologically walk through CFG in top-down order.
|
||
During the traversal, if all the predecessors of a node are
|
||
marked to be in the same region (they all have the same max_hdr),
|
||
then current node is also marked to be a part of that region.
|
||
Otherwise the node starts its own region.
|
||
CFG should be traversed until no further changes are made. On each
|
||
iteration the set of the region heads is extended (the set of those
|
||
blocks that have max_hdr[bbi] == bbi). This set is upper bounded by the
|
||
set of all basic blocks, thus the algorithm is guaranteed to terminate. */
|
||
|
||
while (rescan && iter < max_iter)
|
||
{
|
||
rescan = 0;
|
||
|
||
for (i = nblocks - 1; i >= 0; i--)
|
||
{
|
||
edge e;
|
||
edge_iterator ei;
|
||
int bbn = order[i];
|
||
|
||
if (max_hdr[bbn] != -1 && !TEST_BIT (header, bbn))
|
||
{
|
||
int hdr = -1;
|
||
|
||
FOR_EACH_EDGE (e, ei, BASIC_BLOCK (bbn)->preds)
|
||
{
|
||
int predn = e->src->index;
|
||
|
||
if (predn != ENTRY_BLOCK
|
||
/* If pred wasn't processed in find_rgns. */
|
||
&& max_hdr[predn] != -1
|
||
/* And pred and bb reside in the same loop.
|
||
(Or out of any loop). */
|
||
&& loop_hdr[bbn] == loop_hdr[predn])
|
||
{
|
||
if (hdr == -1)
|
||
/* Then bb extends the containing region of pred. */
|
||
hdr = max_hdr[predn];
|
||
else if (hdr != max_hdr[predn])
|
||
/* Too bad, there are at least two predecessors
|
||
that reside in different regions. Thus, BB should
|
||
begin its own region. */
|
||
{
|
||
hdr = bbn;
|
||
break;
|
||
}
|
||
}
|
||
else
|
||
/* BB starts its own region. */
|
||
{
|
||
hdr = bbn;
|
||
break;
|
||
}
|
||
}
|
||
|
||
if (hdr == bbn)
|
||
{
|
||
/* If BB start its own region,
|
||
update set of headers with BB. */
|
||
SET_BIT (header, bbn);
|
||
rescan = 1;
|
||
}
|
||
else
|
||
gcc_assert (hdr != -1);
|
||
|
||
max_hdr[bbn] = hdr;
|
||
}
|
||
}
|
||
|
||
iter++;
|
||
}
|
||
|
||
/* Statistics were gathered on the SPEC2000 package of tests with
|
||
mainline weekly snapshot gcc-4.1-20051015 on ia64.
|
||
|
||
Statistics for SPECint:
|
||
1 iteration : 1751 cases (38.7%)
|
||
2 iterations: 2770 cases (61.3%)
|
||
Blocks wrapped in regions by find_rgns without extension: 18295 blocks
|
||
Blocks wrapped in regions by 2 iterations in extend_rgns: 23821 blocks
|
||
(We don't count single block regions here).
|
||
|
||
Statistics for SPECfp:
|
||
1 iteration : 621 cases (35.9%)
|
||
2 iterations: 1110 cases (64.1%)
|
||
Blocks wrapped in regions by find_rgns without extension: 6476 blocks
|
||
Blocks wrapped in regions by 2 iterations in extend_rgns: 11155 blocks
|
||
(We don't count single block regions here).
|
||
|
||
By default we do at most 2 iterations.
|
||
This can be overridden with max-sched-extend-regions-iters parameter:
|
||
0 - disable region extension,
|
||
N > 0 - do at most N iterations. */
|
||
|
||
if (sched_verbose && iter != 0)
|
||
fprintf (sched_dump, ";; Region extension iterations: %d%s\n", iter,
|
||
rescan ? "... failed" : "");
|
||
|
||
if (!rescan && iter != 0)
|
||
{
|
||
int *s1 = NULL, s1_sz = 0;
|
||
|
||
/* Save the old statistics for later printout. */
|
||
if (sched_verbose >= 6)
|
||
s1_sz = gather_region_statistics (&s1);
|
||
|
||
/* We have succeeded. Now assemble the regions. */
|
||
for (i = nblocks - 1; i >= 0; i--)
|
||
{
|
||
int bbn = order[i];
|
||
|
||
if (max_hdr[bbn] == bbn)
|
||
/* BBN is a region head. */
|
||
{
|
||
edge e;
|
||
edge_iterator ei;
|
||
int num_bbs = 0, j, num_insns = 0, large;
|
||
|
||
large = too_large (bbn, &num_bbs, &num_insns);
|
||
|
||
degree[bbn] = -1;
|
||
rgn_bb_table[idx] = bbn;
|
||
RGN_BLOCKS (nr_regions) = idx++;
|
||
RGN_DONT_CALC_DEPS (nr_regions) = 0;
|
||
RGN_HAS_REAL_EBB (nr_regions) = 0;
|
||
CONTAINING_RGN (bbn) = nr_regions;
|
||
BLOCK_TO_BB (bbn) = 0;
|
||
|
||
FOR_EACH_EDGE (e, ei, BASIC_BLOCK (bbn)->succs)
|
||
if (e->dest != EXIT_BLOCK_PTR)
|
||
degree[e->dest->index]--;
|
||
|
||
if (!large)
|
||
/* Here we check whether the region is too_large. */
|
||
for (j = i - 1; j >= 0; j--)
|
||
{
|
||
int succn = order[j];
|
||
if (max_hdr[succn] == bbn)
|
||
{
|
||
if ((large = too_large (succn, &num_bbs, &num_insns)))
|
||
break;
|
||
}
|
||
}
|
||
|
||
if (large)
|
||
/* If the region is too_large, then wrap every block of
|
||
the region into single block region.
|
||
Here we wrap region head only. Other blocks are
|
||
processed in the below cycle. */
|
||
{
|
||
RGN_NR_BLOCKS (nr_regions) = 1;
|
||
nr_regions++;
|
||
}
|
||
|
||
num_bbs = 1;
|
||
|
||
for (j = i - 1; j >= 0; j--)
|
||
{
|
||
int succn = order[j];
|
||
|
||
if (max_hdr[succn] == bbn)
|
||
/* This cycle iterates over all basic blocks, that
|
||
are supposed to be in the region with head BBN,
|
||
and wraps them into that region (or in single
|
||
block region). */
|
||
{
|
||
gcc_assert (degree[succn] == 0);
|
||
|
||
degree[succn] = -1;
|
||
rgn_bb_table[idx] = succn;
|
||
BLOCK_TO_BB (succn) = large ? 0 : num_bbs++;
|
||
CONTAINING_RGN (succn) = nr_regions;
|
||
|
||
if (large)
|
||
/* Wrap SUCCN into single block region. */
|
||
{
|
||
RGN_BLOCKS (nr_regions) = idx;
|
||
RGN_NR_BLOCKS (nr_regions) = 1;
|
||
RGN_DONT_CALC_DEPS (nr_regions) = 0;
|
||
RGN_HAS_REAL_EBB (nr_regions) = 0;
|
||
nr_regions++;
|
||
}
|
||
|
||
idx++;
|
||
|
||
FOR_EACH_EDGE (e, ei, BASIC_BLOCK (succn)->succs)
|
||
if (e->dest != EXIT_BLOCK_PTR)
|
||
degree[e->dest->index]--;
|
||
}
|
||
}
|
||
|
||
if (!large)
|
||
{
|
||
RGN_NR_BLOCKS (nr_regions) = num_bbs;
|
||
nr_regions++;
|
||
}
|
||
}
|
||
}
|
||
|
||
if (sched_verbose >= 6)
|
||
{
|
||
int *s2, s2_sz;
|
||
|
||
/* Get the new statistics and print the comparison with the
|
||
one before calling this function. */
|
||
s2_sz = gather_region_statistics (&s2);
|
||
print_region_statistics (s1, s1_sz, s2, s2_sz);
|
||
free (s1);
|
||
free (s2);
|
||
}
|
||
}
|
||
|
||
free (order);
|
||
free (max_hdr);
|
||
|
||
*idxp = idx;
|
||
}
|
||
|
||
/* Functions for regions scheduling information. */
|
||
|
||
/* Compute dominators, probability, and potential-split-edges of bb.
|
||
Assume that these values were already computed for bb's predecessors. */
|
||
|
||
static void
|
||
compute_dom_prob_ps (int bb)
|
||
{
|
||
edge_iterator in_ei;
|
||
edge in_edge;
|
||
|
||
/* We shouldn't have any real ebbs yet. */
|
||
gcc_assert (ebb_head [bb] == bb + current_blocks);
|
||
|
||
if (IS_RGN_ENTRY (bb))
|
||
{
|
||
SET_BIT (dom[bb], 0);
|
||
prob[bb] = REG_BR_PROB_BASE;
|
||
return;
|
||
}
|
||
|
||
prob[bb] = 0;
|
||
|
||
/* Initialize dom[bb] to '111..1'. */
|
||
sbitmap_ones (dom[bb]);
|
||
|
||
FOR_EACH_EDGE (in_edge, in_ei, BASIC_BLOCK (BB_TO_BLOCK (bb))->preds)
|
||
{
|
||
int pred_bb;
|
||
edge out_edge;
|
||
edge_iterator out_ei;
|
||
|
||
if (in_edge->src == ENTRY_BLOCK_PTR)
|
||
continue;
|
||
|
||
pred_bb = BLOCK_TO_BB (in_edge->src->index);
|
||
sbitmap_a_and_b (dom[bb], dom[bb], dom[pred_bb]);
|
||
sbitmap_a_or_b (ancestor_edges[bb],
|
||
ancestor_edges[bb], ancestor_edges[pred_bb]);
|
||
|
||
SET_BIT (ancestor_edges[bb], EDGE_TO_BIT (in_edge));
|
||
|
||
sbitmap_a_or_b (pot_split[bb], pot_split[bb], pot_split[pred_bb]);
|
||
|
||
FOR_EACH_EDGE (out_edge, out_ei, in_edge->src->succs)
|
||
SET_BIT (pot_split[bb], EDGE_TO_BIT (out_edge));
|
||
|
||
prob[bb] += ((prob[pred_bb] * in_edge->probability) / REG_BR_PROB_BASE);
|
||
}
|
||
|
||
SET_BIT (dom[bb], bb);
|
||
sbitmap_difference (pot_split[bb], pot_split[bb], ancestor_edges[bb]);
|
||
|
||
if (sched_verbose >= 2)
|
||
fprintf (sched_dump, ";; bb_prob(%d, %d) = %3d\n", bb, BB_TO_BLOCK (bb),
|
||
(100 * prob[bb]) / REG_BR_PROB_BASE);
|
||
}
|
||
|
||
/* Functions for target info. */
|
||
|
||
/* Compute in BL the list of split-edges of bb_src relatively to bb_trg.
|
||
Note that bb_trg dominates bb_src. */
|
||
|
||
static void
|
||
split_edges (int bb_src, int bb_trg, edgelst *bl)
|
||
{
|
||
sbitmap src = sbitmap_alloc (pot_split[bb_src]->n_bits);
|
||
sbitmap_copy (src, pot_split[bb_src]);
|
||
|
||
sbitmap_difference (src, src, pot_split[bb_trg]);
|
||
extract_edgelst (src, bl);
|
||
sbitmap_free (src);
|
||
}
|
||
|
||
/* Find the valid candidate-source-blocks for the target block TRG, compute
|
||
their probability, and check if they are speculative or not.
|
||
For speculative sources, compute their update-blocks and split-blocks. */
|
||
|
||
static void
|
||
compute_trg_info (int trg)
|
||
{
|
||
candidate *sp;
|
||
edgelst el;
|
||
int i, j, k, update_idx;
|
||
basic_block block;
|
||
sbitmap visited;
|
||
edge_iterator ei;
|
||
edge e;
|
||
|
||
/* Define some of the fields for the target bb as well. */
|
||
sp = candidate_table + trg;
|
||
sp->is_valid = 1;
|
||
sp->is_speculative = 0;
|
||
sp->src_prob = REG_BR_PROB_BASE;
|
||
|
||
visited = sbitmap_alloc (last_basic_block);
|
||
|
||
for (i = trg + 1; i < current_nr_blocks; i++)
|
||
{
|
||
sp = candidate_table + i;
|
||
|
||
sp->is_valid = IS_DOMINATED (i, trg);
|
||
if (sp->is_valid)
|
||
{
|
||
int tf = prob[trg], cf = prob[i];
|
||
|
||
/* In CFGs with low probability edges TF can possibly be zero. */
|
||
sp->src_prob = (tf ? ((cf * REG_BR_PROB_BASE) / tf) : 0);
|
||
sp->is_valid = (sp->src_prob >= min_spec_prob);
|
||
}
|
||
|
||
if (sp->is_valid)
|
||
{
|
||
split_edges (i, trg, &el);
|
||
sp->is_speculative = (el.nr_members) ? 1 : 0;
|
||
if (sp->is_speculative && !flag_schedule_speculative)
|
||
sp->is_valid = 0;
|
||
}
|
||
|
||
if (sp->is_valid)
|
||
{
|
||
/* Compute split blocks and store them in bblst_table.
|
||
The TO block of every split edge is a split block. */
|
||
sp->split_bbs.first_member = &bblst_table[bblst_last];
|
||
sp->split_bbs.nr_members = el.nr_members;
|
||
for (j = 0; j < el.nr_members; bblst_last++, j++)
|
||
bblst_table[bblst_last] = el.first_member[j]->dest;
|
||
sp->update_bbs.first_member = &bblst_table[bblst_last];
|
||
|
||
/* Compute update blocks and store them in bblst_table.
|
||
For every split edge, look at the FROM block, and check
|
||
all out edges. For each out edge that is not a split edge,
|
||
add the TO block to the update block list. This list can end
|
||
up with a lot of duplicates. We need to weed them out to avoid
|
||
overrunning the end of the bblst_table. */
|
||
|
||
update_idx = 0;
|
||
sbitmap_zero (visited);
|
||
for (j = 0; j < el.nr_members; j++)
|
||
{
|
||
block = el.first_member[j]->src;
|
||
FOR_EACH_EDGE (e, ei, block->succs)
|
||
{
|
||
if (!TEST_BIT (visited, e->dest->index))
|
||
{
|
||
for (k = 0; k < el.nr_members; k++)
|
||
if (e == el.first_member[k])
|
||
break;
|
||
|
||
if (k >= el.nr_members)
|
||
{
|
||
bblst_table[bblst_last++] = e->dest;
|
||
SET_BIT (visited, e->dest->index);
|
||
update_idx++;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
sp->update_bbs.nr_members = update_idx;
|
||
|
||
/* Make sure we didn't overrun the end of bblst_table. */
|
||
gcc_assert (bblst_last <= bblst_size);
|
||
}
|
||
else
|
||
{
|
||
sp->split_bbs.nr_members = sp->update_bbs.nr_members = 0;
|
||
|
||
sp->is_speculative = 0;
|
||
sp->src_prob = 0;
|
||
}
|
||
}
|
||
|
||
sbitmap_free (visited);
|
||
}
|
||
|
||
/* Print candidates info, for debugging purposes. Callable from debugger. */
|
||
|
||
void
|
||
debug_candidate (int i)
|
||
{
|
||
if (!candidate_table[i].is_valid)
|
||
return;
|
||
|
||
if (candidate_table[i].is_speculative)
|
||
{
|
||
int j;
|
||
fprintf (sched_dump, "src b %d bb %d speculative \n", BB_TO_BLOCK (i), i);
|
||
|
||
fprintf (sched_dump, "split path: ");
|
||
for (j = 0; j < candidate_table[i].split_bbs.nr_members; j++)
|
||
{
|
||
int b = candidate_table[i].split_bbs.first_member[j]->index;
|
||
|
||
fprintf (sched_dump, " %d ", b);
|
||
}
|
||
fprintf (sched_dump, "\n");
|
||
|
||
fprintf (sched_dump, "update path: ");
|
||
for (j = 0; j < candidate_table[i].update_bbs.nr_members; j++)
|
||
{
|
||
int b = candidate_table[i].update_bbs.first_member[j]->index;
|
||
|
||
fprintf (sched_dump, " %d ", b);
|
||
}
|
||
fprintf (sched_dump, "\n");
|
||
}
|
||
else
|
||
{
|
||
fprintf (sched_dump, " src %d equivalent\n", BB_TO_BLOCK (i));
|
||
}
|
||
}
|
||
|
||
/* Print candidates info, for debugging purposes. Callable from debugger. */
|
||
|
||
void
|
||
debug_candidates (int trg)
|
||
{
|
||
int i;
|
||
|
||
fprintf (sched_dump, "----------- candidate table: target: b=%d bb=%d ---\n",
|
||
BB_TO_BLOCK (trg), trg);
|
||
for (i = trg + 1; i < current_nr_blocks; i++)
|
||
debug_candidate (i);
|
||
}
|
||
|
||
/* Functions for speculative scheduling. */
|
||
|
||
/* Return 0 if x is a set of a register alive in the beginning of one
|
||
of the split-blocks of src, otherwise return 1. */
|
||
|
||
static int
|
||
check_live_1 (int src, rtx x)
|
||
{
|
||
int i;
|
||
int regno;
|
||
rtx reg = SET_DEST (x);
|
||
|
||
if (reg == 0)
|
||
return 1;
|
||
|
||
while (GET_CODE (reg) == SUBREG
|
||
|| GET_CODE (reg) == ZERO_EXTRACT
|
||
|| GET_CODE (reg) == STRICT_LOW_PART)
|
||
reg = XEXP (reg, 0);
|
||
|
||
if (GET_CODE (reg) == PARALLEL)
|
||
{
|
||
int i;
|
||
|
||
for (i = XVECLEN (reg, 0) - 1; i >= 0; i--)
|
||
if (XEXP (XVECEXP (reg, 0, i), 0) != 0)
|
||
if (check_live_1 (src, XEXP (XVECEXP (reg, 0, i), 0)))
|
||
return 1;
|
||
|
||
return 0;
|
||
}
|
||
|
||
if (!REG_P (reg))
|
||
return 1;
|
||
|
||
regno = REGNO (reg);
|
||
|
||
if (regno < FIRST_PSEUDO_REGISTER && global_regs[regno])
|
||
{
|
||
/* Global registers are assumed live. */
|
||
return 0;
|
||
}
|
||
else
|
||
{
|
||
if (regno < FIRST_PSEUDO_REGISTER)
|
||
{
|
||
/* Check for hard registers. */
|
||
int j = hard_regno_nregs[regno][GET_MODE (reg)];
|
||
while (--j >= 0)
|
||
{
|
||
for (i = 0; i < candidate_table[src].split_bbs.nr_members; i++)
|
||
{
|
||
basic_block b = candidate_table[src].split_bbs.first_member[i];
|
||
|
||
/* We can have split blocks, that were recently generated.
|
||
such blocks are always outside current region. */
|
||
gcc_assert (glat_start[b->index]
|
||
|| CONTAINING_RGN (b->index)
|
||
!= CONTAINING_RGN (BB_TO_BLOCK (src)));
|
||
if (!glat_start[b->index]
|
||
|| REGNO_REG_SET_P (glat_start[b->index],
|
||
regno + j))
|
||
{
|
||
return 0;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
else
|
||
{
|
||
/* Check for pseudo registers. */
|
||
for (i = 0; i < candidate_table[src].split_bbs.nr_members; i++)
|
||
{
|
||
basic_block b = candidate_table[src].split_bbs.first_member[i];
|
||
|
||
gcc_assert (glat_start[b->index]
|
||
|| CONTAINING_RGN (b->index)
|
||
!= CONTAINING_RGN (BB_TO_BLOCK (src)));
|
||
if (!glat_start[b->index]
|
||
|| REGNO_REG_SET_P (glat_start[b->index], regno))
|
||
{
|
||
return 0;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
return 1;
|
||
}
|
||
|
||
/* If x is a set of a register R, mark that R is alive in the beginning
|
||
of every update-block of src. */
|
||
|
||
static void
|
||
update_live_1 (int src, rtx x)
|
||
{
|
||
int i;
|
||
int regno;
|
||
rtx reg = SET_DEST (x);
|
||
|
||
if (reg == 0)
|
||
return;
|
||
|
||
while (GET_CODE (reg) == SUBREG
|
||
|| GET_CODE (reg) == ZERO_EXTRACT
|
||
|| GET_CODE (reg) == STRICT_LOW_PART)
|
||
reg = XEXP (reg, 0);
|
||
|
||
if (GET_CODE (reg) == PARALLEL)
|
||
{
|
||
int i;
|
||
|
||
for (i = XVECLEN (reg, 0) - 1; i >= 0; i--)
|
||
if (XEXP (XVECEXP (reg, 0, i), 0) != 0)
|
||
update_live_1 (src, XEXP (XVECEXP (reg, 0, i), 0));
|
||
|
||
return;
|
||
}
|
||
|
||
if (!REG_P (reg))
|
||
return;
|
||
|
||
/* Global registers are always live, so the code below does not apply
|
||
to them. */
|
||
|
||
regno = REGNO (reg);
|
||
|
||
if (regno >= FIRST_PSEUDO_REGISTER || !global_regs[regno])
|
||
{
|
||
if (regno < FIRST_PSEUDO_REGISTER)
|
||
{
|
||
int j = hard_regno_nregs[regno][GET_MODE (reg)];
|
||
while (--j >= 0)
|
||
{
|
||
for (i = 0; i < candidate_table[src].update_bbs.nr_members; i++)
|
||
{
|
||
basic_block b = candidate_table[src].update_bbs.first_member[i];
|
||
|
||
SET_REGNO_REG_SET (glat_start[b->index], regno + j);
|
||
}
|
||
}
|
||
}
|
||
else
|
||
{
|
||
for (i = 0; i < candidate_table[src].update_bbs.nr_members; i++)
|
||
{
|
||
basic_block b = candidate_table[src].update_bbs.first_member[i];
|
||
|
||
SET_REGNO_REG_SET (glat_start[b->index], regno);
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Return 1 if insn can be speculatively moved from block src to trg,
|
||
otherwise return 0. Called before first insertion of insn to
|
||
ready-list or before the scheduling. */
|
||
|
||
static int
|
||
check_live (rtx insn, int src)
|
||
{
|
||
/* Find the registers set by instruction. */
|
||
if (GET_CODE (PATTERN (insn)) == SET
|
||
|| GET_CODE (PATTERN (insn)) == CLOBBER)
|
||
return check_live_1 (src, PATTERN (insn));
|
||
else if (GET_CODE (PATTERN (insn)) == PARALLEL)
|
||
{
|
||
int j;
|
||
for (j = XVECLEN (PATTERN (insn), 0) - 1; j >= 0; j--)
|
||
if ((GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET
|
||
|| GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == CLOBBER)
|
||
&& !check_live_1 (src, XVECEXP (PATTERN (insn), 0, j)))
|
||
return 0;
|
||
|
||
return 1;
|
||
}
|
||
|
||
return 1;
|
||
}
|
||
|
||
/* Update the live registers info after insn was moved speculatively from
|
||
block src to trg. */
|
||
|
||
static void
|
||
update_live (rtx insn, int src)
|
||
{
|
||
/* Find the registers set by instruction. */
|
||
if (GET_CODE (PATTERN (insn)) == SET
|
||
|| GET_CODE (PATTERN (insn)) == CLOBBER)
|
||
update_live_1 (src, PATTERN (insn));
|
||
else if (GET_CODE (PATTERN (insn)) == PARALLEL)
|
||
{
|
||
int j;
|
||
for (j = XVECLEN (PATTERN (insn), 0) - 1; j >= 0; j--)
|
||
if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET
|
||
|| GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == CLOBBER)
|
||
update_live_1 (src, XVECEXP (PATTERN (insn), 0, j));
|
||
}
|
||
}
|
||
|
||
/* Nonzero if block bb_to is equal to, or reachable from block bb_from. */
|
||
#define IS_REACHABLE(bb_from, bb_to) \
|
||
(bb_from == bb_to \
|
||
|| IS_RGN_ENTRY (bb_from) \
|
||
|| (TEST_BIT (ancestor_edges[bb_to], \
|
||
EDGE_TO_BIT (single_pred_edge (BASIC_BLOCK (BB_TO_BLOCK (bb_from)))))))
|
||
|
||
/* Turns on the fed_by_spec_load flag for insns fed by load_insn. */
|
||
|
||
static void
|
||
set_spec_fed (rtx load_insn)
|
||
{
|
||
rtx link;
|
||
|
||
for (link = INSN_DEPEND (load_insn); link; link = XEXP (link, 1))
|
||
if (GET_MODE (link) == VOIDmode)
|
||
FED_BY_SPEC_LOAD (XEXP (link, 0)) = 1;
|
||
} /* set_spec_fed */
|
||
|
||
/* On the path from the insn to load_insn_bb, find a conditional
|
||
branch depending on insn, that guards the speculative load. */
|
||
|
||
static int
|
||
find_conditional_protection (rtx insn, int load_insn_bb)
|
||
{
|
||
rtx link;
|
||
|
||
/* Iterate through DEF-USE forward dependences. */
|
||
for (link = INSN_DEPEND (insn); link; link = XEXP (link, 1))
|
||
{
|
||
rtx next = XEXP (link, 0);
|
||
if ((CONTAINING_RGN (BLOCK_NUM (next)) ==
|
||
CONTAINING_RGN (BB_TO_BLOCK (load_insn_bb)))
|
||
&& IS_REACHABLE (INSN_BB (next), load_insn_bb)
|
||
&& load_insn_bb != INSN_BB (next)
|
||
&& GET_MODE (link) == VOIDmode
|
||
&& (JUMP_P (next)
|
||
|| find_conditional_protection (next, load_insn_bb)))
|
||
return 1;
|
||
}
|
||
return 0;
|
||
} /* find_conditional_protection */
|
||
|
||
/* Returns 1 if the same insn1 that participates in the computation
|
||
of load_insn's address is feeding a conditional branch that is
|
||
guarding on load_insn. This is true if we find a the two DEF-USE
|
||
chains:
|
||
insn1 -> ... -> conditional-branch
|
||
insn1 -> ... -> load_insn,
|
||
and if a flow path exist:
|
||
insn1 -> ... -> conditional-branch -> ... -> load_insn,
|
||
and if insn1 is on the path
|
||
region-entry -> ... -> bb_trg -> ... load_insn.
|
||
|
||
Locate insn1 by climbing on LOG_LINKS from load_insn.
|
||
Locate the branch by following INSN_DEPEND from insn1. */
|
||
|
||
static int
|
||
is_conditionally_protected (rtx load_insn, int bb_src, int bb_trg)
|
||
{
|
||
rtx link;
|
||
|
||
for (link = LOG_LINKS (load_insn); link; link = XEXP (link, 1))
|
||
{
|
||
rtx insn1 = XEXP (link, 0);
|
||
|
||
/* Must be a DEF-USE dependence upon non-branch. */
|
||
if (GET_MODE (link) != VOIDmode
|
||
|| JUMP_P (insn1))
|
||
continue;
|
||
|
||
/* Must exist a path: region-entry -> ... -> bb_trg -> ... load_insn. */
|
||
if (INSN_BB (insn1) == bb_src
|
||
|| (CONTAINING_RGN (BLOCK_NUM (insn1))
|
||
!= CONTAINING_RGN (BB_TO_BLOCK (bb_src)))
|
||
|| (!IS_REACHABLE (bb_trg, INSN_BB (insn1))
|
||
&& !IS_REACHABLE (INSN_BB (insn1), bb_trg)))
|
||
continue;
|
||
|
||
/* Now search for the conditional-branch. */
|
||
if (find_conditional_protection (insn1, bb_src))
|
||
return 1;
|
||
|
||
/* Recursive step: search another insn1, "above" current insn1. */
|
||
return is_conditionally_protected (insn1, bb_src, bb_trg);
|
||
}
|
||
|
||
/* The chain does not exist. */
|
||
return 0;
|
||
} /* is_conditionally_protected */
|
||
|
||
/* Returns 1 if a clue for "similar load" 'insn2' is found, and hence
|
||
load_insn can move speculatively from bb_src to bb_trg. All the
|
||
following must hold:
|
||
|
||
(1) both loads have 1 base register (PFREE_CANDIDATEs).
|
||
(2) load_insn and load1 have a def-use dependence upon
|
||
the same insn 'insn1'.
|
||
(3) either load2 is in bb_trg, or:
|
||
- there's only one split-block, and
|
||
- load1 is on the escape path, and
|
||
|
||
From all these we can conclude that the two loads access memory
|
||
addresses that differ at most by a constant, and hence if moving
|
||
load_insn would cause an exception, it would have been caused by
|
||
load2 anyhow. */
|
||
|
||
static int
|
||
is_pfree (rtx load_insn, int bb_src, int bb_trg)
|
||
{
|
||
rtx back_link;
|
||
candidate *candp = candidate_table + bb_src;
|
||
|
||
if (candp->split_bbs.nr_members != 1)
|
||
/* Must have exactly one escape block. */
|
||
return 0;
|
||
|
||
for (back_link = LOG_LINKS (load_insn);
|
||
back_link; back_link = XEXP (back_link, 1))
|
||
{
|
||
rtx insn1 = XEXP (back_link, 0);
|
||
|
||
if (GET_MODE (back_link) == VOIDmode)
|
||
{
|
||
/* Found a DEF-USE dependence (insn1, load_insn). */
|
||
rtx fore_link;
|
||
|
||
for (fore_link = INSN_DEPEND (insn1);
|
||
fore_link; fore_link = XEXP (fore_link, 1))
|
||
{
|
||
rtx insn2 = XEXP (fore_link, 0);
|
||
if (GET_MODE (fore_link) == VOIDmode)
|
||
{
|
||
/* Found a DEF-USE dependence (insn1, insn2). */
|
||
if (haifa_classify_insn (insn2) != PFREE_CANDIDATE)
|
||
/* insn2 not guaranteed to be a 1 base reg load. */
|
||
continue;
|
||
|
||
if (INSN_BB (insn2) == bb_trg)
|
||
/* insn2 is the similar load, in the target block. */
|
||
return 1;
|
||
|
||
if (*(candp->split_bbs.first_member) == BLOCK_FOR_INSN (insn2))
|
||
/* insn2 is a similar load, in a split-block. */
|
||
return 1;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Couldn't find a similar load. */
|
||
return 0;
|
||
} /* is_pfree */
|
||
|
||
/* Return 1 if load_insn is prisky (i.e. if load_insn is fed by
|
||
a load moved speculatively, or if load_insn is protected by
|
||
a compare on load_insn's address). */
|
||
|
||
static int
|
||
is_prisky (rtx load_insn, int bb_src, int bb_trg)
|
||
{
|
||
if (FED_BY_SPEC_LOAD (load_insn))
|
||
return 1;
|
||
|
||
if (LOG_LINKS (load_insn) == NULL)
|
||
/* Dependence may 'hide' out of the region. */
|
||
return 1;
|
||
|
||
if (is_conditionally_protected (load_insn, bb_src, bb_trg))
|
||
return 1;
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* Insn is a candidate to be moved speculatively from bb_src to bb_trg.
|
||
Return 1 if insn is exception-free (and the motion is valid)
|
||
and 0 otherwise. */
|
||
|
||
static int
|
||
is_exception_free (rtx insn, int bb_src, int bb_trg)
|
||
{
|
||
int insn_class = haifa_classify_insn (insn);
|
||
|
||
/* Handle non-load insns. */
|
||
switch (insn_class)
|
||
{
|
||
case TRAP_FREE:
|
||
return 1;
|
||
case TRAP_RISKY:
|
||
return 0;
|
||
default:;
|
||
}
|
||
|
||
/* Handle loads. */
|
||
if (!flag_schedule_speculative_load)
|
||
return 0;
|
||
IS_LOAD_INSN (insn) = 1;
|
||
switch (insn_class)
|
||
{
|
||
case IFREE:
|
||
return (1);
|
||
case IRISKY:
|
||
return 0;
|
||
case PFREE_CANDIDATE:
|
||
if (is_pfree (insn, bb_src, bb_trg))
|
||
return 1;
|
||
/* Don't 'break' here: PFREE-candidate is also PRISKY-candidate. */
|
||
case PRISKY_CANDIDATE:
|
||
if (!flag_schedule_speculative_load_dangerous
|
||
|| is_prisky (insn, bb_src, bb_trg))
|
||
return 0;
|
||
break;
|
||
default:;
|
||
}
|
||
|
||
return flag_schedule_speculative_load_dangerous;
|
||
}
|
||
|
||
/* The number of insns from the current block scheduled so far. */
|
||
static int sched_target_n_insns;
|
||
/* The number of insns from the current block to be scheduled in total. */
|
||
static int target_n_insns;
|
||
/* The number of insns from the entire region scheduled so far. */
|
||
static int sched_n_insns;
|
||
|
||
/* Implementations of the sched_info functions for region scheduling. */
|
||
static void init_ready_list (void);
|
||
static int can_schedule_ready_p (rtx);
|
||
static void begin_schedule_ready (rtx, rtx);
|
||
static ds_t new_ready (rtx, ds_t);
|
||
static int schedule_more_p (void);
|
||
static const char *rgn_print_insn (rtx, int);
|
||
static int rgn_rank (rtx, rtx);
|
||
static int contributes_to_priority (rtx, rtx);
|
||
static void compute_jump_reg_dependencies (rtx, regset, regset, regset);
|
||
|
||
/* Functions for speculative scheduling. */
|
||
static void add_remove_insn (rtx, int);
|
||
static void extend_regions (void);
|
||
static void add_block1 (basic_block, basic_block);
|
||
static void fix_recovery_cfg (int, int, int);
|
||
static basic_block advance_target_bb (basic_block, rtx);
|
||
static void check_dead_notes1 (int, sbitmap);
|
||
#ifdef ENABLE_CHECKING
|
||
static int region_head_or_leaf_p (basic_block, int);
|
||
#endif
|
||
|
||
/* Return nonzero if there are more insns that should be scheduled. */
|
||
|
||
static int
|
||
schedule_more_p (void)
|
||
{
|
||
return sched_target_n_insns < target_n_insns;
|
||
}
|
||
|
||
/* Add all insns that are initially ready to the ready list READY. Called
|
||
once before scheduling a set of insns. */
|
||
|
||
static void
|
||
init_ready_list (void)
|
||
{
|
||
rtx prev_head = current_sched_info->prev_head;
|
||
rtx next_tail = current_sched_info->next_tail;
|
||
int bb_src;
|
||
rtx insn;
|
||
|
||
target_n_insns = 0;
|
||
sched_target_n_insns = 0;
|
||
sched_n_insns = 0;
|
||
|
||
/* Print debugging information. */
|
||
if (sched_verbose >= 5)
|
||
debug_dependencies ();
|
||
|
||
/* Prepare current target block info. */
|
||
if (current_nr_blocks > 1)
|
||
{
|
||
candidate_table = XNEWVEC (candidate, current_nr_blocks);
|
||
|
||
bblst_last = 0;
|
||
/* bblst_table holds split blocks and update blocks for each block after
|
||
the current one in the region. split blocks and update blocks are
|
||
the TO blocks of region edges, so there can be at most rgn_nr_edges
|
||
of them. */
|
||
bblst_size = (current_nr_blocks - target_bb) * rgn_nr_edges;
|
||
bblst_table = XNEWVEC (basic_block, bblst_size);
|
||
|
||
edgelst_last = 0;
|
||
edgelst_table = XNEWVEC (edge, rgn_nr_edges);
|
||
|
||
compute_trg_info (target_bb);
|
||
}
|
||
|
||
/* Initialize ready list with all 'ready' insns in target block.
|
||
Count number of insns in the target block being scheduled. */
|
||
for (insn = NEXT_INSN (prev_head); insn != next_tail; insn = NEXT_INSN (insn))
|
||
{
|
||
try_ready (insn);
|
||
target_n_insns++;
|
||
|
||
gcc_assert (!(TODO_SPEC (insn) & BEGIN_CONTROL));
|
||
}
|
||
|
||
/* Add to ready list all 'ready' insns in valid source blocks.
|
||
For speculative insns, check-live, exception-free, and
|
||
issue-delay. */
|
||
for (bb_src = target_bb + 1; bb_src < current_nr_blocks; bb_src++)
|
||
if (IS_VALID (bb_src))
|
||
{
|
||
rtx src_head;
|
||
rtx src_next_tail;
|
||
rtx tail, head;
|
||
|
||
get_ebb_head_tail (EBB_FIRST_BB (bb_src), EBB_LAST_BB (bb_src),
|
||
&head, &tail);
|
||
src_next_tail = NEXT_INSN (tail);
|
||
src_head = head;
|
||
|
||
for (insn = src_head; insn != src_next_tail; insn = NEXT_INSN (insn))
|
||
if (INSN_P (insn))
|
||
try_ready (insn);
|
||
}
|
||
}
|
||
|
||
/* Called after taking INSN from the ready list. Returns nonzero if this
|
||
insn can be scheduled, nonzero if we should silently discard it. */
|
||
|
||
static int
|
||
can_schedule_ready_p (rtx insn)
|
||
{
|
||
/* An interblock motion? */
|
||
if (INSN_BB (insn) != target_bb
|
||
&& IS_SPECULATIVE_INSN (insn)
|
||
&& !check_live (insn, INSN_BB (insn)))
|
||
return 0;
|
||
else
|
||
return 1;
|
||
}
|
||
|
||
/* Updates counter and other information. Split from can_schedule_ready_p ()
|
||
because when we schedule insn speculatively then insn passed to
|
||
can_schedule_ready_p () differs from the one passed to
|
||
begin_schedule_ready (). */
|
||
static void
|
||
begin_schedule_ready (rtx insn, rtx last ATTRIBUTE_UNUSED)
|
||
{
|
||
/* An interblock motion? */
|
||
if (INSN_BB (insn) != target_bb)
|
||
{
|
||
if (IS_SPECULATIVE_INSN (insn))
|
||
{
|
||
gcc_assert (check_live (insn, INSN_BB (insn)));
|
||
|
||
update_live (insn, INSN_BB (insn));
|
||
|
||
/* For speculative load, mark insns fed by it. */
|
||
if (IS_LOAD_INSN (insn) || FED_BY_SPEC_LOAD (insn))
|
||
set_spec_fed (insn);
|
||
|
||
nr_spec++;
|
||
}
|
||
nr_inter++;
|
||
}
|
||
else
|
||
{
|
||
/* In block motion. */
|
||
sched_target_n_insns++;
|
||
}
|
||
sched_n_insns++;
|
||
}
|
||
|
||
/* Called after INSN has all its hard dependencies resolved and the speculation
|
||
of type TS is enough to overcome them all.
|
||
Return nonzero if it should be moved to the ready list or the queue, or zero
|
||
if we should silently discard it. */
|
||
static ds_t
|
||
new_ready (rtx next, ds_t ts)
|
||
{
|
||
if (INSN_BB (next) != target_bb)
|
||
{
|
||
int not_ex_free = 0;
|
||
|
||
/* For speculative insns, before inserting to ready/queue,
|
||
check live, exception-free, and issue-delay. */
|
||
if (!IS_VALID (INSN_BB (next))
|
||
|| CANT_MOVE (next)
|
||
|| (IS_SPECULATIVE_INSN (next)
|
||
&& ((recog_memoized (next) >= 0
|
||
&& min_insn_conflict_delay (curr_state, next, next)
|
||
> PARAM_VALUE (PARAM_MAX_SCHED_INSN_CONFLICT_DELAY))
|
||
|| IS_SPECULATION_CHECK_P (next)
|
||
|| !check_live (next, INSN_BB (next))
|
||
|| (not_ex_free = !is_exception_free (next, INSN_BB (next),
|
||
target_bb)))))
|
||
{
|
||
if (not_ex_free
|
||
/* We are here because is_exception_free () == false.
|
||
But we possibly can handle that with control speculation. */
|
||
&& current_sched_info->flags & DO_SPECULATION)
|
||
/* Here we got new control-speculative instruction. */
|
||
ts = set_dep_weak (ts, BEGIN_CONTROL, MAX_DEP_WEAK);
|
||
else
|
||
ts = (ts & ~SPECULATIVE) | HARD_DEP;
|
||
}
|
||
}
|
||
|
||
return ts;
|
||
}
|
||
|
||
/* Return a string that contains the insn uid and optionally anything else
|
||
necessary to identify this insn in an output. It's valid to use a
|
||
static buffer for this. The ALIGNED parameter should cause the string
|
||
to be formatted so that multiple output lines will line up nicely. */
|
||
|
||
static const char *
|
||
rgn_print_insn (rtx insn, int aligned)
|
||
{
|
||
static char tmp[80];
|
||
|
||
if (aligned)
|
||
sprintf (tmp, "b%3d: i%4d", INSN_BB (insn), INSN_UID (insn));
|
||
else
|
||
{
|
||
if (current_nr_blocks > 1 && INSN_BB (insn) != target_bb)
|
||
sprintf (tmp, "%d/b%d", INSN_UID (insn), INSN_BB (insn));
|
||
else
|
||
sprintf (tmp, "%d", INSN_UID (insn));
|
||
}
|
||
return tmp;
|
||
}
|
||
|
||
/* Compare priority of two insns. Return a positive number if the second
|
||
insn is to be preferred for scheduling, and a negative one if the first
|
||
is to be preferred. Zero if they are equally good. */
|
||
|
||
static int
|
||
rgn_rank (rtx insn1, rtx insn2)
|
||
{
|
||
/* Some comparison make sense in interblock scheduling only. */
|
||
if (INSN_BB (insn1) != INSN_BB (insn2))
|
||
{
|
||
int spec_val, prob_val;
|
||
|
||
/* Prefer an inblock motion on an interblock motion. */
|
||
if ((INSN_BB (insn2) == target_bb) && (INSN_BB (insn1) != target_bb))
|
||
return 1;
|
||
if ((INSN_BB (insn1) == target_bb) && (INSN_BB (insn2) != target_bb))
|
||
return -1;
|
||
|
||
/* Prefer a useful motion on a speculative one. */
|
||
spec_val = IS_SPECULATIVE_INSN (insn1) - IS_SPECULATIVE_INSN (insn2);
|
||
if (spec_val)
|
||
return spec_val;
|
||
|
||
/* Prefer a more probable (speculative) insn. */
|
||
prob_val = INSN_PROBABILITY (insn2) - INSN_PROBABILITY (insn1);
|
||
if (prob_val)
|
||
return prob_val;
|
||
}
|
||
return 0;
|
||
}
|
||
|
||
/* NEXT is an instruction that depends on INSN (a backward dependence);
|
||
return nonzero if we should include this dependence in priority
|
||
calculations. */
|
||
|
||
static int
|
||
contributes_to_priority (rtx next, rtx insn)
|
||
{
|
||
/* NEXT and INSN reside in one ebb. */
|
||
return BLOCK_TO_BB (BLOCK_NUM (next)) == BLOCK_TO_BB (BLOCK_NUM (insn));
|
||
}
|
||
|
||
/* INSN is a JUMP_INSN, COND_SET is the set of registers that are
|
||
conditionally set before INSN. Store the set of registers that
|
||
must be considered as used by this jump in USED and that of
|
||
registers that must be considered as set in SET. */
|
||
|
||
static void
|
||
compute_jump_reg_dependencies (rtx insn ATTRIBUTE_UNUSED,
|
||
regset cond_exec ATTRIBUTE_UNUSED,
|
||
regset used ATTRIBUTE_UNUSED,
|
||
regset set ATTRIBUTE_UNUSED)
|
||
{
|
||
/* Nothing to do here, since we postprocess jumps in
|
||
add_branch_dependences. */
|
||
}
|
||
|
||
/* Used in schedule_insns to initialize current_sched_info for scheduling
|
||
regions (or single basic blocks). */
|
||
|
||
static struct sched_info region_sched_info =
|
||
{
|
||
init_ready_list,
|
||
can_schedule_ready_p,
|
||
schedule_more_p,
|
||
new_ready,
|
||
rgn_rank,
|
||
rgn_print_insn,
|
||
contributes_to_priority,
|
||
compute_jump_reg_dependencies,
|
||
|
||
NULL, NULL,
|
||
NULL, NULL,
|
||
0, 0, 0,
|
||
|
||
add_remove_insn,
|
||
begin_schedule_ready,
|
||
add_block1,
|
||
advance_target_bb,
|
||
fix_recovery_cfg,
|
||
#ifdef ENABLE_CHECKING
|
||
region_head_or_leaf_p,
|
||
#endif
|
||
SCHED_RGN | USE_GLAT
|
||
#ifdef ENABLE_CHECKING
|
||
| DETACH_LIFE_INFO
|
||
#endif
|
||
};
|
||
|
||
/* Determine if PAT sets a CLASS_LIKELY_SPILLED_P register. */
|
||
|
||
static bool
|
||
sets_likely_spilled (rtx pat)
|
||
{
|
||
bool ret = false;
|
||
note_stores (pat, sets_likely_spilled_1, &ret);
|
||
return ret;
|
||
}
|
||
|
||
static void
|
||
sets_likely_spilled_1 (rtx x, rtx pat, void *data)
|
||
{
|
||
bool *ret = (bool *) data;
|
||
|
||
if (GET_CODE (pat) == SET
|
||
&& REG_P (x)
|
||
&& REGNO (x) < FIRST_PSEUDO_REGISTER
|
||
&& CLASS_LIKELY_SPILLED_P (REGNO_REG_CLASS (REGNO (x))))
|
||
*ret = true;
|
||
}
|
||
|
||
/* Add dependences so that branches are scheduled to run last in their
|
||
block. */
|
||
|
||
static void
|
||
add_branch_dependences (rtx head, rtx tail)
|
||
{
|
||
rtx insn, last;
|
||
|
||
/* For all branches, calls, uses, clobbers, cc0 setters, and instructions
|
||
that can throw exceptions, force them to remain in order at the end of
|
||
the block by adding dependencies and giving the last a high priority.
|
||
There may be notes present, and prev_head may also be a note.
|
||
|
||
Branches must obviously remain at the end. Calls should remain at the
|
||
end since moving them results in worse register allocation. Uses remain
|
||
at the end to ensure proper register allocation.
|
||
|
||
cc0 setters remain at the end because they can't be moved away from
|
||
their cc0 user.
|
||
|
||
COND_EXEC insns cannot be moved past a branch (see e.g. PR17808).
|
||
|
||
Insns setting CLASS_LIKELY_SPILLED_P registers (usually return values)
|
||
are not moved before reload because we can wind up with register
|
||
allocation failures. */
|
||
|
||
insn = tail;
|
||
last = 0;
|
||
while (CALL_P (insn)
|
||
|| JUMP_P (insn)
|
||
|| (NONJUMP_INSN_P (insn)
|
||
&& (GET_CODE (PATTERN (insn)) == USE
|
||
|| GET_CODE (PATTERN (insn)) == CLOBBER
|
||
|| can_throw_internal (insn)
|
||
#ifdef HAVE_cc0
|
||
|| sets_cc0_p (PATTERN (insn))
|
||
#endif
|
||
|| (!reload_completed
|
||
&& sets_likely_spilled (PATTERN (insn)))))
|
||
|| NOTE_P (insn))
|
||
{
|
||
if (!NOTE_P (insn))
|
||
{
|
||
if (last != 0 && !find_insn_list (insn, LOG_LINKS (last)))
|
||
{
|
||
if (! sched_insns_conditions_mutex_p (last, insn))
|
||
add_dependence (last, insn, REG_DEP_ANTI);
|
||
INSN_REF_COUNT (insn)++;
|
||
}
|
||
|
||
CANT_MOVE (insn) = 1;
|
||
|
||
last = insn;
|
||
}
|
||
|
||
/* Don't overrun the bounds of the basic block. */
|
||
if (insn == head)
|
||
break;
|
||
|
||
insn = PREV_INSN (insn);
|
||
}
|
||
|
||
/* Make sure these insns are scheduled last in their block. */
|
||
insn = last;
|
||
if (insn != 0)
|
||
while (insn != head)
|
||
{
|
||
insn = prev_nonnote_insn (insn);
|
||
|
||
if (INSN_REF_COUNT (insn) != 0)
|
||
continue;
|
||
|
||
if (! sched_insns_conditions_mutex_p (last, insn))
|
||
add_dependence (last, insn, REG_DEP_ANTI);
|
||
INSN_REF_COUNT (insn) = 1;
|
||
}
|
||
|
||
#ifdef HAVE_conditional_execution
|
||
/* Finally, if the block ends in a jump, and we are doing intra-block
|
||
scheduling, make sure that the branch depends on any COND_EXEC insns
|
||
inside the block to avoid moving the COND_EXECs past the branch insn.
|
||
|
||
We only have to do this after reload, because (1) before reload there
|
||
are no COND_EXEC insns, and (2) the region scheduler is an intra-block
|
||
scheduler after reload.
|
||
|
||
FIXME: We could in some cases move COND_EXEC insns past the branch if
|
||
this scheduler would be a little smarter. Consider this code:
|
||
|
||
T = [addr]
|
||
C ? addr += 4
|
||
!C ? X += 12
|
||
C ? T += 1
|
||
C ? jump foo
|
||
|
||
On a target with a one cycle stall on a memory access the optimal
|
||
sequence would be:
|
||
|
||
T = [addr]
|
||
C ? addr += 4
|
||
C ? T += 1
|
||
C ? jump foo
|
||
!C ? X += 12
|
||
|
||
We don't want to put the 'X += 12' before the branch because it just
|
||
wastes a cycle of execution time when the branch is taken.
|
||
|
||
Note that in the example "!C" will always be true. That is another
|
||
possible improvement for handling COND_EXECs in this scheduler: it
|
||
could remove always-true predicates. */
|
||
|
||
if (!reload_completed || ! JUMP_P (tail))
|
||
return;
|
||
|
||
insn = tail;
|
||
while (insn != head)
|
||
{
|
||
insn = PREV_INSN (insn);
|
||
|
||
/* Note that we want to add this dependency even when
|
||
sched_insns_conditions_mutex_p returns true. The whole point
|
||
is that we _want_ this dependency, even if these insns really
|
||
are independent. */
|
||
if (INSN_P (insn) && GET_CODE (PATTERN (insn)) == COND_EXEC)
|
||
add_dependence (tail, insn, REG_DEP_ANTI);
|
||
}
|
||
#endif
|
||
}
|
||
|
||
/* Data structures for the computation of data dependences in a regions. We
|
||
keep one `deps' structure for every basic block. Before analyzing the
|
||
data dependences for a bb, its variables are initialized as a function of
|
||
the variables of its predecessors. When the analysis for a bb completes,
|
||
we save the contents to the corresponding bb_deps[bb] variable. */
|
||
|
||
static struct deps *bb_deps;
|
||
|
||
/* Duplicate the INSN_LIST elements of COPY and prepend them to OLD. */
|
||
|
||
static rtx
|
||
concat_INSN_LIST (rtx copy, rtx old)
|
||
{
|
||
rtx new = old;
|
||
for (; copy ; copy = XEXP (copy, 1))
|
||
new = alloc_INSN_LIST (XEXP (copy, 0), new);
|
||
return new;
|
||
}
|
||
|
||
static void
|
||
concat_insn_mem_list (rtx copy_insns, rtx copy_mems, rtx *old_insns_p,
|
||
rtx *old_mems_p)
|
||
{
|
||
rtx new_insns = *old_insns_p;
|
||
rtx new_mems = *old_mems_p;
|
||
|
||
while (copy_insns)
|
||
{
|
||
new_insns = alloc_INSN_LIST (XEXP (copy_insns, 0), new_insns);
|
||
new_mems = alloc_EXPR_LIST (VOIDmode, XEXP (copy_mems, 0), new_mems);
|
||
copy_insns = XEXP (copy_insns, 1);
|
||
copy_mems = XEXP (copy_mems, 1);
|
||
}
|
||
|
||
*old_insns_p = new_insns;
|
||
*old_mems_p = new_mems;
|
||
}
|
||
|
||
/* After computing the dependencies for block BB, propagate the dependencies
|
||
found in TMP_DEPS to the successors of the block. */
|
||
static void
|
||
propagate_deps (int bb, struct deps *pred_deps)
|
||
{
|
||
basic_block block = BASIC_BLOCK (BB_TO_BLOCK (bb));
|
||
edge_iterator ei;
|
||
edge e;
|
||
|
||
/* bb's structures are inherited by its successors. */
|
||
FOR_EACH_EDGE (e, ei, block->succs)
|
||
{
|
||
struct deps *succ_deps;
|
||
unsigned reg;
|
||
reg_set_iterator rsi;
|
||
|
||
/* Only bbs "below" bb, in the same region, are interesting. */
|
||
if (e->dest == EXIT_BLOCK_PTR
|
||
|| CONTAINING_RGN (block->index) != CONTAINING_RGN (e->dest->index)
|
||
|| BLOCK_TO_BB (e->dest->index) <= bb)
|
||
continue;
|
||
|
||
succ_deps = bb_deps + BLOCK_TO_BB (e->dest->index);
|
||
|
||
/* The reg_last lists are inherited by successor. */
|
||
EXECUTE_IF_SET_IN_REG_SET (&pred_deps->reg_last_in_use, 0, reg, rsi)
|
||
{
|
||
struct deps_reg *pred_rl = &pred_deps->reg_last[reg];
|
||
struct deps_reg *succ_rl = &succ_deps->reg_last[reg];
|
||
|
||
succ_rl->uses = concat_INSN_LIST (pred_rl->uses, succ_rl->uses);
|
||
succ_rl->sets = concat_INSN_LIST (pred_rl->sets, succ_rl->sets);
|
||
succ_rl->clobbers = concat_INSN_LIST (pred_rl->clobbers,
|
||
succ_rl->clobbers);
|
||
succ_rl->uses_length += pred_rl->uses_length;
|
||
succ_rl->clobbers_length += pred_rl->clobbers_length;
|
||
}
|
||
IOR_REG_SET (&succ_deps->reg_last_in_use, &pred_deps->reg_last_in_use);
|
||
|
||
/* Mem read/write lists are inherited by successor. */
|
||
concat_insn_mem_list (pred_deps->pending_read_insns,
|
||
pred_deps->pending_read_mems,
|
||
&succ_deps->pending_read_insns,
|
||
&succ_deps->pending_read_mems);
|
||
concat_insn_mem_list (pred_deps->pending_write_insns,
|
||
pred_deps->pending_write_mems,
|
||
&succ_deps->pending_write_insns,
|
||
&succ_deps->pending_write_mems);
|
||
|
||
succ_deps->last_pending_memory_flush
|
||
= concat_INSN_LIST (pred_deps->last_pending_memory_flush,
|
||
succ_deps->last_pending_memory_flush);
|
||
|
||
succ_deps->pending_lists_length += pred_deps->pending_lists_length;
|
||
succ_deps->pending_flush_length += pred_deps->pending_flush_length;
|
||
|
||
/* last_function_call is inherited by successor. */
|
||
succ_deps->last_function_call
|
||
= concat_INSN_LIST (pred_deps->last_function_call,
|
||
succ_deps->last_function_call);
|
||
|
||
/* sched_before_next_call is inherited by successor. */
|
||
succ_deps->sched_before_next_call
|
||
= concat_INSN_LIST (pred_deps->sched_before_next_call,
|
||
succ_deps->sched_before_next_call);
|
||
}
|
||
|
||
/* These lists should point to the right place, for correct
|
||
freeing later. */
|
||
bb_deps[bb].pending_read_insns = pred_deps->pending_read_insns;
|
||
bb_deps[bb].pending_read_mems = pred_deps->pending_read_mems;
|
||
bb_deps[bb].pending_write_insns = pred_deps->pending_write_insns;
|
||
bb_deps[bb].pending_write_mems = pred_deps->pending_write_mems;
|
||
|
||
/* Can't allow these to be freed twice. */
|
||
pred_deps->pending_read_insns = 0;
|
||
pred_deps->pending_read_mems = 0;
|
||
pred_deps->pending_write_insns = 0;
|
||
pred_deps->pending_write_mems = 0;
|
||
}
|
||
|
||
/* Compute backward dependences inside bb. In a multiple blocks region:
|
||
(1) a bb is analyzed after its predecessors, and (2) the lists in
|
||
effect at the end of bb (after analyzing for bb) are inherited by
|
||
bb's successors.
|
||
|
||
Specifically for reg-reg data dependences, the block insns are
|
||
scanned by sched_analyze () top-to-bottom. Two lists are
|
||
maintained by sched_analyze (): reg_last[].sets for register DEFs,
|
||
and reg_last[].uses for register USEs.
|
||
|
||
When analysis is completed for bb, we update for its successors:
|
||
; - DEFS[succ] = Union (DEFS [succ], DEFS [bb])
|
||
; - USES[succ] = Union (USES [succ], DEFS [bb])
|
||
|
||
The mechanism for computing mem-mem data dependence is very
|
||
similar, and the result is interblock dependences in the region. */
|
||
|
||
static void
|
||
compute_block_backward_dependences (int bb)
|
||
{
|
||
rtx head, tail;
|
||
struct deps tmp_deps;
|
||
|
||
tmp_deps = bb_deps[bb];
|
||
|
||
/* Do the analysis for this block. */
|
||
gcc_assert (EBB_FIRST_BB (bb) == EBB_LAST_BB (bb));
|
||
get_ebb_head_tail (EBB_FIRST_BB (bb), EBB_LAST_BB (bb), &head, &tail);
|
||
sched_analyze (&tmp_deps, head, tail);
|
||
add_branch_dependences (head, tail);
|
||
|
||
if (current_nr_blocks > 1)
|
||
propagate_deps (bb, &tmp_deps);
|
||
|
||
/* Free up the INSN_LISTs. */
|
||
free_deps (&tmp_deps);
|
||
}
|
||
|
||
/* Remove all INSN_LISTs and EXPR_LISTs from the pending lists and add
|
||
them to the unused_*_list variables, so that they can be reused. */
|
||
|
||
static void
|
||
free_pending_lists (void)
|
||
{
|
||
int bb;
|
||
|
||
for (bb = 0; bb < current_nr_blocks; bb++)
|
||
{
|
||
free_INSN_LIST_list (&bb_deps[bb].pending_read_insns);
|
||
free_INSN_LIST_list (&bb_deps[bb].pending_write_insns);
|
||
free_EXPR_LIST_list (&bb_deps[bb].pending_read_mems);
|
||
free_EXPR_LIST_list (&bb_deps[bb].pending_write_mems);
|
||
}
|
||
}
|
||
|
||
/* Print dependences for debugging, callable from debugger. */
|
||
|
||
void
|
||
debug_dependencies (void)
|
||
{
|
||
int bb;
|
||
|
||
fprintf (sched_dump, ";; --------------- forward dependences: ------------ \n");
|
||
for (bb = 0; bb < current_nr_blocks; bb++)
|
||
{
|
||
rtx head, tail;
|
||
rtx next_tail;
|
||
rtx insn;
|
||
|
||
gcc_assert (EBB_FIRST_BB (bb) == EBB_LAST_BB (bb));
|
||
get_ebb_head_tail (EBB_FIRST_BB (bb), EBB_LAST_BB (bb), &head, &tail);
|
||
next_tail = NEXT_INSN (tail);
|
||
fprintf (sched_dump, "\n;; --- Region Dependences --- b %d bb %d \n",
|
||
BB_TO_BLOCK (bb), bb);
|
||
|
||
fprintf (sched_dump, ";; %7s%6s%6s%6s%6s%6s%14s\n",
|
||
"insn", "code", "bb", "dep", "prio", "cost",
|
||
"reservation");
|
||
fprintf (sched_dump, ";; %7s%6s%6s%6s%6s%6s%14s\n",
|
||
"----", "----", "--", "---", "----", "----",
|
||
"-----------");
|
||
|
||
for (insn = head; insn != next_tail; insn = NEXT_INSN (insn))
|
||
{
|
||
rtx link;
|
||
|
||
if (! INSN_P (insn))
|
||
{
|
||
int n;
|
||
fprintf (sched_dump, ";; %6d ", INSN_UID (insn));
|
||
if (NOTE_P (insn))
|
||
{
|
||
n = NOTE_LINE_NUMBER (insn);
|
||
if (n < 0)
|
||
fprintf (sched_dump, "%s\n", GET_NOTE_INSN_NAME (n));
|
||
else
|
||
{
|
||
expanded_location xloc;
|
||
NOTE_EXPANDED_LOCATION (xloc, insn);
|
||
fprintf (sched_dump, "line %d, file %s\n",
|
||
xloc.line, xloc.file);
|
||
}
|
||
}
|
||
else
|
||
fprintf (sched_dump, " {%s}\n", GET_RTX_NAME (GET_CODE (insn)));
|
||
continue;
|
||
}
|
||
|
||
fprintf (sched_dump,
|
||
";; %s%5d%6d%6d%6d%6d%6d ",
|
||
(SCHED_GROUP_P (insn) ? "+" : " "),
|
||
INSN_UID (insn),
|
||
INSN_CODE (insn),
|
||
INSN_BB (insn),
|
||
INSN_DEP_COUNT (insn),
|
||
INSN_PRIORITY (insn),
|
||
insn_cost (insn, 0, 0));
|
||
|
||
if (recog_memoized (insn) < 0)
|
||
fprintf (sched_dump, "nothing");
|
||
else
|
||
print_reservation (sched_dump, insn);
|
||
|
||
fprintf (sched_dump, "\t: ");
|
||
for (link = INSN_DEPEND (insn); link; link = XEXP (link, 1))
|
||
fprintf (sched_dump, "%d ", INSN_UID (XEXP (link, 0)));
|
||
fprintf (sched_dump, "\n");
|
||
}
|
||
}
|
||
fprintf (sched_dump, "\n");
|
||
}
|
||
|
||
/* Returns true if all the basic blocks of the current region have
|
||
NOTE_DISABLE_SCHED_OF_BLOCK which means not to schedule that region. */
|
||
static bool
|
||
sched_is_disabled_for_current_region_p (void)
|
||
{
|
||
int bb;
|
||
|
||
for (bb = 0; bb < current_nr_blocks; bb++)
|
||
if (!(BASIC_BLOCK (BB_TO_BLOCK (bb))->flags & BB_DISABLE_SCHEDULE))
|
||
return false;
|
||
|
||
return true;
|
||
}
|
||
|
||
/* Schedule a region. A region is either an inner loop, a loop-free
|
||
subroutine, or a single basic block. Each bb in the region is
|
||
scheduled after its flow predecessors. */
|
||
|
||
static void
|
||
schedule_region (int rgn)
|
||
{
|
||
basic_block block;
|
||
edge_iterator ei;
|
||
edge e;
|
||
int bb;
|
||
int sched_rgn_n_insns = 0;
|
||
|
||
rgn_n_insns = 0;
|
||
/* Set variables for the current region. */
|
||
current_nr_blocks = RGN_NR_BLOCKS (rgn);
|
||
current_blocks = RGN_BLOCKS (rgn);
|
||
|
||
/* See comments in add_block1, for what reasons we allocate +1 element. */
|
||
ebb_head = xrealloc (ebb_head, (current_nr_blocks + 1) * sizeof (*ebb_head));
|
||
for (bb = 0; bb <= current_nr_blocks; bb++)
|
||
ebb_head[bb] = current_blocks + bb;
|
||
|
||
/* Don't schedule region that is marked by
|
||
NOTE_DISABLE_SCHED_OF_BLOCK. */
|
||
if (sched_is_disabled_for_current_region_p ())
|
||
return;
|
||
|
||
if (!RGN_DONT_CALC_DEPS (rgn))
|
||
{
|
||
init_deps_global ();
|
||
|
||
/* Initializations for region data dependence analysis. */
|
||
bb_deps = XNEWVEC (struct deps, current_nr_blocks);
|
||
for (bb = 0; bb < current_nr_blocks; bb++)
|
||
init_deps (bb_deps + bb);
|
||
|
||
/* Compute LOG_LINKS. */
|
||
for (bb = 0; bb < current_nr_blocks; bb++)
|
||
compute_block_backward_dependences (bb);
|
||
|
||
/* Compute INSN_DEPEND. */
|
||
for (bb = current_nr_blocks - 1; bb >= 0; bb--)
|
||
{
|
||
rtx head, tail;
|
||
|
||
gcc_assert (EBB_FIRST_BB (bb) == EBB_LAST_BB (bb));
|
||
get_ebb_head_tail (EBB_FIRST_BB (bb), EBB_LAST_BB (bb), &head, &tail);
|
||
|
||
compute_forward_dependences (head, tail);
|
||
|
||
if (targetm.sched.dependencies_evaluation_hook)
|
||
targetm.sched.dependencies_evaluation_hook (head, tail);
|
||
}
|
||
|
||
free_pending_lists ();
|
||
|
||
finish_deps_global ();
|
||
|
||
free (bb_deps);
|
||
}
|
||
else
|
||
/* This is a recovery block. It is always a single block region. */
|
||
gcc_assert (current_nr_blocks == 1);
|
||
|
||
/* Set priorities. */
|
||
current_sched_info->sched_max_insns_priority = 0;
|
||
for (bb = 0; bb < current_nr_blocks; bb++)
|
||
{
|
||
rtx head, tail;
|
||
|
||
gcc_assert (EBB_FIRST_BB (bb) == EBB_LAST_BB (bb));
|
||
get_ebb_head_tail (EBB_FIRST_BB (bb), EBB_LAST_BB (bb), &head, &tail);
|
||
|
||
rgn_n_insns += set_priorities (head, tail);
|
||
}
|
||
current_sched_info->sched_max_insns_priority++;
|
||
|
||
/* Compute interblock info: probabilities, split-edges, dominators, etc. */
|
||
if (current_nr_blocks > 1)
|
||
{
|
||
prob = XNEWVEC (int, current_nr_blocks);
|
||
|
||
dom = sbitmap_vector_alloc (current_nr_blocks, current_nr_blocks);
|
||
sbitmap_vector_zero (dom, current_nr_blocks);
|
||
|
||
/* Use ->aux to implement EDGE_TO_BIT mapping. */
|
||
rgn_nr_edges = 0;
|
||
FOR_EACH_BB (block)
|
||
{
|
||
if (CONTAINING_RGN (block->index) != rgn)
|
||
continue;
|
||
FOR_EACH_EDGE (e, ei, block->succs)
|
||
SET_EDGE_TO_BIT (e, rgn_nr_edges++);
|
||
}
|
||
|
||
rgn_edges = XNEWVEC (edge, rgn_nr_edges);
|
||
rgn_nr_edges = 0;
|
||
FOR_EACH_BB (block)
|
||
{
|
||
if (CONTAINING_RGN (block->index) != rgn)
|
||
continue;
|
||
FOR_EACH_EDGE (e, ei, block->succs)
|
||
rgn_edges[rgn_nr_edges++] = e;
|
||
}
|
||
|
||
/* Split edges. */
|
||
pot_split = sbitmap_vector_alloc (current_nr_blocks, rgn_nr_edges);
|
||
sbitmap_vector_zero (pot_split, current_nr_blocks);
|
||
ancestor_edges = sbitmap_vector_alloc (current_nr_blocks, rgn_nr_edges);
|
||
sbitmap_vector_zero (ancestor_edges, current_nr_blocks);
|
||
|
||
/* Compute probabilities, dominators, split_edges. */
|
||
for (bb = 0; bb < current_nr_blocks; bb++)
|
||
compute_dom_prob_ps (bb);
|
||
|
||
/* Cleanup ->aux used for EDGE_TO_BIT mapping. */
|
||
/* We don't need them anymore. But we want to avoid duplication of
|
||
aux fields in the newly created edges. */
|
||
FOR_EACH_BB (block)
|
||
{
|
||
if (CONTAINING_RGN (block->index) != rgn)
|
||
continue;
|
||
FOR_EACH_EDGE (e, ei, block->succs)
|
||
e->aux = NULL;
|
||
}
|
||
}
|
||
|
||
/* Now we can schedule all blocks. */
|
||
for (bb = 0; bb < current_nr_blocks; bb++)
|
||
{
|
||
basic_block first_bb, last_bb, curr_bb;
|
||
rtx head, tail;
|
||
int b = BB_TO_BLOCK (bb);
|
||
|
||
first_bb = EBB_FIRST_BB (bb);
|
||
last_bb = EBB_LAST_BB (bb);
|
||
|
||
get_ebb_head_tail (first_bb, last_bb, &head, &tail);
|
||
|
||
if (no_real_insns_p (head, tail))
|
||
{
|
||
gcc_assert (first_bb == last_bb);
|
||
continue;
|
||
}
|
||
|
||
current_sched_info->prev_head = PREV_INSN (head);
|
||
current_sched_info->next_tail = NEXT_INSN (tail);
|
||
|
||
if (write_symbols != NO_DEBUG)
|
||
{
|
||
save_line_notes (b, head, tail);
|
||
rm_line_notes (head, tail);
|
||
}
|
||
|
||
/* rm_other_notes only removes notes which are _inside_ the
|
||
block---that is, it won't remove notes before the first real insn
|
||
or after the last real insn of the block. So if the first insn
|
||
has a REG_SAVE_NOTE which would otherwise be emitted before the
|
||
insn, it is redundant with the note before the start of the
|
||
block, and so we have to take it out. */
|
||
if (INSN_P (head))
|
||
{
|
||
rtx note;
|
||
|
||
for (note = REG_NOTES (head); note; note = XEXP (note, 1))
|
||
if (REG_NOTE_KIND (note) == REG_SAVE_NOTE)
|
||
remove_note (head, note);
|
||
}
|
||
else
|
||
/* This means that first block in ebb is empty.
|
||
It looks to me as an impossible thing. There at least should be
|
||
a recovery check, that caused the splitting. */
|
||
gcc_unreachable ();
|
||
|
||
/* Remove remaining note insns from the block, save them in
|
||
note_list. These notes are restored at the end of
|
||
schedule_block (). */
|
||
rm_other_notes (head, tail);
|
||
|
||
unlink_bb_notes (first_bb, last_bb);
|
||
|
||
target_bb = bb;
|
||
|
||
gcc_assert (flag_schedule_interblock || current_nr_blocks == 1);
|
||
current_sched_info->queue_must_finish_empty = current_nr_blocks == 1;
|
||
|
||
curr_bb = first_bb;
|
||
schedule_block (&curr_bb, rgn_n_insns);
|
||
gcc_assert (EBB_FIRST_BB (bb) == first_bb);
|
||
sched_rgn_n_insns += sched_n_insns;
|
||
|
||
/* Clean up. */
|
||
if (current_nr_blocks > 1)
|
||
{
|
||
free (candidate_table);
|
||
free (bblst_table);
|
||
free (edgelst_table);
|
||
}
|
||
}
|
||
|
||
/* Sanity check: verify that all region insns were scheduled. */
|
||
gcc_assert (sched_rgn_n_insns == rgn_n_insns);
|
||
|
||
/* Restore line notes. */
|
||
if (write_symbols != NO_DEBUG)
|
||
{
|
||
for (bb = 0; bb < current_nr_blocks; bb++)
|
||
{
|
||
rtx head, tail;
|
||
|
||
get_ebb_head_tail (EBB_FIRST_BB (bb), EBB_LAST_BB (bb), &head, &tail);
|
||
restore_line_notes (head, tail);
|
||
}
|
||
}
|
||
|
||
/* Done with this region. */
|
||
|
||
if (current_nr_blocks > 1)
|
||
{
|
||
free (prob);
|
||
sbitmap_vector_free (dom);
|
||
sbitmap_vector_free (pot_split);
|
||
sbitmap_vector_free (ancestor_edges);
|
||
free (rgn_edges);
|
||
}
|
||
}
|
||
|
||
/* Indexed by region, holds the number of death notes found in that region.
|
||
Used for consistency checks. */
|
||
static int *deaths_in_region;
|
||
|
||
/* Initialize data structures for region scheduling. */
|
||
|
||
static void
|
||
init_regions (void)
|
||
{
|
||
sbitmap blocks;
|
||
int rgn;
|
||
|
||
nr_regions = 0;
|
||
rgn_table = 0;
|
||
rgn_bb_table = 0;
|
||
block_to_bb = 0;
|
||
containing_rgn = 0;
|
||
extend_regions ();
|
||
|
||
/* Compute regions for scheduling. */
|
||
if (reload_completed
|
||
|| n_basic_blocks == NUM_FIXED_BLOCKS + 1
|
||
|| !flag_schedule_interblock
|
||
|| is_cfg_nonregular ())
|
||
{
|
||
find_single_block_region ();
|
||
}
|
||
else
|
||
{
|
||
/* Compute the dominators and post dominators. */
|
||
calculate_dominance_info (CDI_DOMINATORS);
|
||
|
||
/* Find regions. */
|
||
find_rgns ();
|
||
|
||
if (sched_verbose >= 3)
|
||
debug_regions ();
|
||
|
||
/* For now. This will move as more and more of haifa is converted
|
||
to using the cfg code in flow.c. */
|
||
free_dominance_info (CDI_DOMINATORS);
|
||
}
|
||
RGN_BLOCKS (nr_regions) = RGN_BLOCKS (nr_regions - 1) +
|
||
RGN_NR_BLOCKS (nr_regions - 1);
|
||
|
||
|
||
if (CHECK_DEAD_NOTES)
|
||
{
|
||
blocks = sbitmap_alloc (last_basic_block);
|
||
deaths_in_region = XNEWVEC (int, nr_regions);
|
||
/* Remove all death notes from the subroutine. */
|
||
for (rgn = 0; rgn < nr_regions; rgn++)
|
||
check_dead_notes1 (rgn, blocks);
|
||
|
||
sbitmap_free (blocks);
|
||
}
|
||
else
|
||
count_or_remove_death_notes (NULL, 1);
|
||
}
|
||
|
||
/* The one entry point in this file. */
|
||
|
||
void
|
||
schedule_insns (void)
|
||
{
|
||
sbitmap large_region_blocks, blocks;
|
||
int rgn;
|
||
int any_large_regions;
|
||
basic_block bb;
|
||
|
||
/* Taking care of this degenerate case makes the rest of
|
||
this code simpler. */
|
||
if (n_basic_blocks == NUM_FIXED_BLOCKS)
|
||
return;
|
||
|
||
nr_inter = 0;
|
||
nr_spec = 0;
|
||
|
||
/* We need current_sched_info in init_dependency_caches, which is
|
||
invoked via sched_init. */
|
||
current_sched_info = ®ion_sched_info;
|
||
|
||
sched_init ();
|
||
|
||
min_spec_prob = ((PARAM_VALUE (PARAM_MIN_SPEC_PROB) * REG_BR_PROB_BASE)
|
||
/ 100);
|
||
|
||
init_regions ();
|
||
|
||
/* EBB_HEAD is a region-scope structure. But we realloc it for
|
||
each region to save time/memory/something else. */
|
||
ebb_head = 0;
|
||
|
||
/* Schedule every region in the subroutine. */
|
||
for (rgn = 0; rgn < nr_regions; rgn++)
|
||
schedule_region (rgn);
|
||
|
||
free(ebb_head);
|
||
|
||
/* Update life analysis for the subroutine. Do single block regions
|
||
first so that we can verify that live_at_start didn't change. Then
|
||
do all other blocks. */
|
||
/* ??? There is an outside possibility that update_life_info, or more
|
||
to the point propagate_block, could get called with nonzero flags
|
||
more than once for one basic block. This would be kinda bad if it
|
||
were to happen, since REG_INFO would be accumulated twice for the
|
||
block, and we'd have twice the REG_DEAD notes.
|
||
|
||
I'm fairly certain that this _shouldn't_ happen, since I don't think
|
||
that live_at_start should change at region heads. Not sure what the
|
||
best way to test for this kind of thing... */
|
||
|
||
if (current_sched_info->flags & DETACH_LIFE_INFO)
|
||
/* this flag can be set either by the target or by ENABLE_CHECKING. */
|
||
attach_life_info ();
|
||
|
||
allocate_reg_life_data ();
|
||
|
||
any_large_regions = 0;
|
||
large_region_blocks = sbitmap_alloc (last_basic_block);
|
||
sbitmap_zero (large_region_blocks);
|
||
FOR_EACH_BB (bb)
|
||
SET_BIT (large_region_blocks, bb->index);
|
||
|
||
blocks = sbitmap_alloc (last_basic_block);
|
||
sbitmap_zero (blocks);
|
||
|
||
/* Update life information. For regions consisting of multiple blocks
|
||
we've possibly done interblock scheduling that affects global liveness.
|
||
For regions consisting of single blocks we need to do only local
|
||
liveness. */
|
||
for (rgn = 0; rgn < nr_regions; rgn++)
|
||
if (RGN_NR_BLOCKS (rgn) > 1
|
||
/* Or the only block of this region has been split. */
|
||
|| RGN_HAS_REAL_EBB (rgn)
|
||
/* New blocks (e.g. recovery blocks) should be processed
|
||
as parts of large regions. */
|
||
|| !glat_start[rgn_bb_table[RGN_BLOCKS (rgn)]])
|
||
any_large_regions = 1;
|
||
else
|
||
{
|
||
SET_BIT (blocks, rgn_bb_table[RGN_BLOCKS (rgn)]);
|
||
RESET_BIT (large_region_blocks, rgn_bb_table[RGN_BLOCKS (rgn)]);
|
||
}
|
||
|
||
/* Don't update reg info after reload, since that affects
|
||
regs_ever_live, which should not change after reload. */
|
||
update_life_info (blocks, UPDATE_LIFE_LOCAL,
|
||
(reload_completed ? PROP_DEATH_NOTES
|
||
: (PROP_DEATH_NOTES | PROP_REG_INFO)));
|
||
if (any_large_regions)
|
||
{
|
||
update_life_info (large_region_blocks, UPDATE_LIFE_GLOBAL,
|
||
(reload_completed ? PROP_DEATH_NOTES
|
||
: (PROP_DEATH_NOTES | PROP_REG_INFO)));
|
||
|
||
#ifdef ENABLE_CHECKING
|
||
check_reg_live (true);
|
||
#endif
|
||
}
|
||
|
||
if (CHECK_DEAD_NOTES)
|
||
{
|
||
/* Verify the counts of basic block notes in single basic block
|
||
regions. */
|
||
for (rgn = 0; rgn < nr_regions; rgn++)
|
||
if (RGN_NR_BLOCKS (rgn) == 1)
|
||
{
|
||
sbitmap_zero (blocks);
|
||
SET_BIT (blocks, rgn_bb_table[RGN_BLOCKS (rgn)]);
|
||
|
||
gcc_assert (deaths_in_region[rgn]
|
||
== count_or_remove_death_notes (blocks, 0));
|
||
}
|
||
free (deaths_in_region);
|
||
}
|
||
|
||
/* Reposition the prologue and epilogue notes in case we moved the
|
||
prologue/epilogue insns. */
|
||
if (reload_completed)
|
||
reposition_prologue_and_epilogue_notes (get_insns ());
|
||
|
||
/* Delete redundant line notes. */
|
||
if (write_symbols != NO_DEBUG)
|
||
rm_redundant_line_notes ();
|
||
|
||
if (sched_verbose)
|
||
{
|
||
if (reload_completed == 0 && flag_schedule_interblock)
|
||
{
|
||
fprintf (sched_dump,
|
||
"\n;; Procedure interblock/speculative motions == %d/%d \n",
|
||
nr_inter, nr_spec);
|
||
}
|
||
else
|
||
gcc_assert (nr_inter <= 0);
|
||
fprintf (sched_dump, "\n\n");
|
||
}
|
||
|
||
/* Clean up. */
|
||
free (rgn_table);
|
||
free (rgn_bb_table);
|
||
free (block_to_bb);
|
||
free (containing_rgn);
|
||
|
||
sched_finish ();
|
||
|
||
sbitmap_free (blocks);
|
||
sbitmap_free (large_region_blocks);
|
||
}
|
||
|
||
/* INSN has been added to/removed from current region. */
|
||
static void
|
||
add_remove_insn (rtx insn, int remove_p)
|
||
{
|
||
if (!remove_p)
|
||
rgn_n_insns++;
|
||
else
|
||
rgn_n_insns--;
|
||
|
||
if (INSN_BB (insn) == target_bb)
|
||
{
|
||
if (!remove_p)
|
||
target_n_insns++;
|
||
else
|
||
target_n_insns--;
|
||
}
|
||
}
|
||
|
||
/* Extend internal data structures. */
|
||
static void
|
||
extend_regions (void)
|
||
{
|
||
rgn_table = XRESIZEVEC (region, rgn_table, n_basic_blocks);
|
||
rgn_bb_table = XRESIZEVEC (int, rgn_bb_table, n_basic_blocks);
|
||
block_to_bb = XRESIZEVEC (int, block_to_bb, last_basic_block);
|
||
containing_rgn = XRESIZEVEC (int, containing_rgn, last_basic_block);
|
||
}
|
||
|
||
/* BB was added to ebb after AFTER. */
|
||
static void
|
||
add_block1 (basic_block bb, basic_block after)
|
||
{
|
||
extend_regions ();
|
||
|
||
if (after == 0 || after == EXIT_BLOCK_PTR)
|
||
{
|
||
int i;
|
||
|
||
i = RGN_BLOCKS (nr_regions);
|
||
/* I - first free position in rgn_bb_table. */
|
||
|
||
rgn_bb_table[i] = bb->index;
|
||
RGN_NR_BLOCKS (nr_regions) = 1;
|
||
RGN_DONT_CALC_DEPS (nr_regions) = after == EXIT_BLOCK_PTR;
|
||
RGN_HAS_REAL_EBB (nr_regions) = 0;
|
||
CONTAINING_RGN (bb->index) = nr_regions;
|
||
BLOCK_TO_BB (bb->index) = 0;
|
||
|
||
nr_regions++;
|
||
|
||
RGN_BLOCKS (nr_regions) = i + 1;
|
||
|
||
if (CHECK_DEAD_NOTES)
|
||
{
|
||
sbitmap blocks = sbitmap_alloc (last_basic_block);
|
||
deaths_in_region = xrealloc (deaths_in_region, nr_regions *
|
||
sizeof (*deaths_in_region));
|
||
|
||
check_dead_notes1 (nr_regions - 1, blocks);
|
||
|
||
sbitmap_free (blocks);
|
||
}
|
||
}
|
||
else
|
||
{
|
||
int i, pos;
|
||
|
||
/* We need to fix rgn_table, block_to_bb, containing_rgn
|
||
and ebb_head. */
|
||
|
||
BLOCK_TO_BB (bb->index) = BLOCK_TO_BB (after->index);
|
||
|
||
/* We extend ebb_head to one more position to
|
||
easily find the last position of the last ebb in
|
||
the current region. Thus, ebb_head[BLOCK_TO_BB (after) + 1]
|
||
is _always_ valid for access. */
|
||
|
||
i = BLOCK_TO_BB (after->index) + 1;
|
||
pos = ebb_head[i] - 1;
|
||
/* Now POS is the index of the last block in the region. */
|
||
|
||
/* Find index of basic block AFTER. */
|
||
for (; rgn_bb_table[pos] != after->index; pos--);
|
||
|
||
pos++;
|
||
gcc_assert (pos > ebb_head[i - 1]);
|
||
|
||
/* i - ebb right after "AFTER". */
|
||
/* ebb_head[i] - VALID. */
|
||
|
||
/* Source position: ebb_head[i]
|
||
Destination position: ebb_head[i] + 1
|
||
Last position:
|
||
RGN_BLOCKS (nr_regions) - 1
|
||
Number of elements to copy: (last_position) - (source_position) + 1
|
||
*/
|
||
|
||
memmove (rgn_bb_table + pos + 1,
|
||
rgn_bb_table + pos,
|
||
((RGN_BLOCKS (nr_regions) - 1) - (pos) + 1)
|
||
* sizeof (*rgn_bb_table));
|
||
|
||
rgn_bb_table[pos] = bb->index;
|
||
|
||
for (; i <= current_nr_blocks; i++)
|
||
ebb_head [i]++;
|
||
|
||
i = CONTAINING_RGN (after->index);
|
||
CONTAINING_RGN (bb->index) = i;
|
||
|
||
RGN_HAS_REAL_EBB (i) = 1;
|
||
|
||
for (++i; i <= nr_regions; i++)
|
||
RGN_BLOCKS (i)++;
|
||
|
||
/* We don't need to call check_dead_notes1 () because this new block
|
||
is just a split of the old. We don't want to count anything twice. */
|
||
}
|
||
}
|
||
|
||
/* Fix internal data after interblock movement of jump instruction.
|
||
For parameter meaning please refer to
|
||
sched-int.h: struct sched_info: fix_recovery_cfg. */
|
||
static void
|
||
fix_recovery_cfg (int bbi, int check_bbi, int check_bb_nexti)
|
||
{
|
||
int old_pos, new_pos, i;
|
||
|
||
BLOCK_TO_BB (check_bb_nexti) = BLOCK_TO_BB (bbi);
|
||
|
||
for (old_pos = ebb_head[BLOCK_TO_BB (check_bbi) + 1] - 1;
|
||
rgn_bb_table[old_pos] != check_bb_nexti;
|
||
old_pos--);
|
||
gcc_assert (old_pos > ebb_head[BLOCK_TO_BB (check_bbi)]);
|
||
|
||
for (new_pos = ebb_head[BLOCK_TO_BB (bbi) + 1] - 1;
|
||
rgn_bb_table[new_pos] != bbi;
|
||
new_pos--);
|
||
new_pos++;
|
||
gcc_assert (new_pos > ebb_head[BLOCK_TO_BB (bbi)]);
|
||
|
||
gcc_assert (new_pos < old_pos);
|
||
|
||
memmove (rgn_bb_table + new_pos + 1,
|
||
rgn_bb_table + new_pos,
|
||
(old_pos - new_pos) * sizeof (*rgn_bb_table));
|
||
|
||
rgn_bb_table[new_pos] = check_bb_nexti;
|
||
|
||
for (i = BLOCK_TO_BB (bbi) + 1; i <= BLOCK_TO_BB (check_bbi); i++)
|
||
ebb_head[i]++;
|
||
}
|
||
|
||
/* Return next block in ebb chain. For parameter meaning please refer to
|
||
sched-int.h: struct sched_info: advance_target_bb. */
|
||
static basic_block
|
||
advance_target_bb (basic_block bb, rtx insn)
|
||
{
|
||
if (insn)
|
||
return 0;
|
||
|
||
gcc_assert (BLOCK_TO_BB (bb->index) == target_bb
|
||
&& BLOCK_TO_BB (bb->next_bb->index) == target_bb);
|
||
return bb->next_bb;
|
||
}
|
||
|
||
/* Count and remove death notes in region RGN, which consists of blocks
|
||
with indecies in BLOCKS. */
|
||
static void
|
||
check_dead_notes1 (int rgn, sbitmap blocks)
|
||
{
|
||
int b;
|
||
|
||
sbitmap_zero (blocks);
|
||
for (b = RGN_NR_BLOCKS (rgn) - 1; b >= 0; --b)
|
||
SET_BIT (blocks, rgn_bb_table[RGN_BLOCKS (rgn) + b]);
|
||
|
||
deaths_in_region[rgn] = count_or_remove_death_notes (blocks, 1);
|
||
}
|
||
|
||
#ifdef ENABLE_CHECKING
|
||
/* Return non zero, if BB is head or leaf (depending of LEAF_P) block in
|
||
current region. For more information please refer to
|
||
sched-int.h: struct sched_info: region_head_or_leaf_p. */
|
||
static int
|
||
region_head_or_leaf_p (basic_block bb, int leaf_p)
|
||
{
|
||
if (!leaf_p)
|
||
return bb->index == rgn_bb_table[RGN_BLOCKS (CONTAINING_RGN (bb->index))];
|
||
else
|
||
{
|
||
int i;
|
||
edge e;
|
||
edge_iterator ei;
|
||
|
||
i = CONTAINING_RGN (bb->index);
|
||
|
||
FOR_EACH_EDGE (e, ei, bb->succs)
|
||
if (e->dest != EXIT_BLOCK_PTR
|
||
&& CONTAINING_RGN (e->dest->index) == i
|
||
/* except self-loop. */
|
||
&& e->dest != bb)
|
||
return 0;
|
||
|
||
return 1;
|
||
}
|
||
}
|
||
#endif /* ENABLE_CHECKING */
|
||
|
||
#endif
|
||
|
||
static bool
|
||
gate_handle_sched (void)
|
||
{
|
||
#ifdef INSN_SCHEDULING
|
||
return flag_schedule_insns;
|
||
#else
|
||
return 0;
|
||
#endif
|
||
}
|
||
|
||
/* Run instruction scheduler. */
|
||
static unsigned int
|
||
rest_of_handle_sched (void)
|
||
{
|
||
#ifdef INSN_SCHEDULING
|
||
/* Do control and data sched analysis,
|
||
and write some of the results to dump file. */
|
||
|
||
schedule_insns ();
|
||
#endif
|
||
return 0;
|
||
}
|
||
|
||
static bool
|
||
gate_handle_sched2 (void)
|
||
{
|
||
#ifdef INSN_SCHEDULING
|
||
return optimize > 0 && flag_schedule_insns_after_reload;
|
||
#else
|
||
return 0;
|
||
#endif
|
||
}
|
||
|
||
/* Run second scheduling pass after reload. */
|
||
static unsigned int
|
||
rest_of_handle_sched2 (void)
|
||
{
|
||
#ifdef INSN_SCHEDULING
|
||
/* Do control and data sched analysis again,
|
||
and write some more of the results to dump file. */
|
||
|
||
split_all_insns (1);
|
||
|
||
if (flag_sched2_use_superblocks || flag_sched2_use_traces)
|
||
{
|
||
schedule_ebbs ();
|
||
/* No liveness updating code yet, but it should be easy to do.
|
||
reg-stack recomputes the liveness when needed for now. */
|
||
count_or_remove_death_notes (NULL, 1);
|
||
cleanup_cfg (CLEANUP_EXPENSIVE);
|
||
}
|
||
else
|
||
schedule_insns ();
|
||
#endif
|
||
return 0;
|
||
}
|
||
|
||
struct tree_opt_pass pass_sched =
|
||
{
|
||
"sched1", /* name */
|
||
gate_handle_sched, /* gate */
|
||
rest_of_handle_sched, /* execute */
|
||
NULL, /* sub */
|
||
NULL, /* next */
|
||
0, /* static_pass_number */
|
||
TV_SCHED, /* tv_id */
|
||
0, /* properties_required */
|
||
0, /* properties_provided */
|
||
0, /* properties_destroyed */
|
||
0, /* todo_flags_start */
|
||
TODO_dump_func |
|
||
TODO_ggc_collect, /* todo_flags_finish */
|
||
'S' /* letter */
|
||
};
|
||
|
||
struct tree_opt_pass pass_sched2 =
|
||
{
|
||
"sched2", /* name */
|
||
gate_handle_sched2, /* gate */
|
||
rest_of_handle_sched2, /* execute */
|
||
NULL, /* sub */
|
||
NULL, /* next */
|
||
0, /* static_pass_number */
|
||
TV_SCHED2, /* tv_id */
|
||
0, /* properties_required */
|
||
0, /* properties_provided */
|
||
0, /* properties_destroyed */
|
||
0, /* todo_flags_start */
|
||
TODO_dump_func |
|
||
TODO_ggc_collect, /* todo_flags_finish */
|
||
'R' /* letter */
|
||
};
|
||
|