blob: f75098c2bec94ba472e467c7da0f04c4e1af77d1 [file] [log] [blame]
/* Scanning of rtl for dataflow analysis.
Copyright (C) 1999-2017 Free Software Foundation, Inc.
Originally contributed by Michael P. Hayes
(m.hayes@elec.canterbury.ac.nz, mhayes@redhat.com)
Major rewrite contributed by Danny Berlin (dberlin@dberlin.org)
and Kenneth Zadeck (zadeck@naturalbridge.com).
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3. If not see
<http://www.gnu.org/licenses/>. */
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "backend.h"
#include "target.h"
#include "rtl.h"
#include "tree.h"
#include "df.h"
#include "memmodel.h"
#include "tm_p.h"
#include "regs.h"
#include "emit-rtl.h" /* FIXME: Can go away once crtl is moved to rtl.h. */
#include "dumpfile.h"
/* The set of hard registers in eliminables[i].from. */
static HARD_REG_SET elim_reg_set;
/* Initialize ur_in and ur_out as if all hard registers were partially
available. */
struct df_collection_rec
{
auto_vec<df_ref, 128> def_vec;
auto_vec<df_ref, 32> use_vec;
auto_vec<df_ref, 32> eq_use_vec;
auto_vec<df_mw_hardreg *, 32> mw_vec;
};
static void df_ref_record (enum df_ref_class, struct df_collection_rec *,
rtx, rtx *,
basic_block, struct df_insn_info *,
enum df_ref_type, int ref_flags);
static void df_def_record_1 (struct df_collection_rec *, rtx *,
basic_block, struct df_insn_info *,
int ref_flags);
static void df_defs_record (struct df_collection_rec *, rtx,
basic_block, struct df_insn_info *,
int ref_flags);
static void df_uses_record (struct df_collection_rec *,
rtx *, enum df_ref_type,
basic_block, struct df_insn_info *,
int ref_flags);
static void df_install_ref_incremental (df_ref);
static void df_insn_refs_collect (struct df_collection_rec*,
basic_block, struct df_insn_info *);
static void df_canonize_collection_rec (struct df_collection_rec *);
static void df_get_regular_block_artificial_uses (bitmap);
static void df_get_eh_block_artificial_uses (bitmap);
static void df_record_entry_block_defs (bitmap);
static void df_record_exit_block_uses (bitmap);
static void df_get_exit_block_use_set (bitmap);
static void df_get_entry_block_def_set (bitmap);
static void df_grow_ref_info (struct df_ref_info *, unsigned int);
static void df_ref_chain_delete_du_chain (df_ref);
static void df_ref_chain_delete (df_ref);
static void df_refs_add_to_chains (struct df_collection_rec *,
basic_block, rtx_insn *, unsigned int);
static bool df_insn_refs_verify (struct df_collection_rec *, basic_block,
rtx_insn *, bool);
static void df_entry_block_defs_collect (struct df_collection_rec *, bitmap);
static void df_exit_block_uses_collect (struct df_collection_rec *, bitmap);
static void df_install_ref (df_ref, struct df_reg_info *,
struct df_ref_info *, bool);
static int df_ref_compare (df_ref, df_ref);
static int df_ref_ptr_compare (const void *, const void *);
static int df_mw_compare (const df_mw_hardreg *, const df_mw_hardreg *);
static int df_mw_ptr_compare (const void *, const void *);
static void df_insn_info_delete (unsigned int);
/* Indexed by hardware reg number, is true if that register is ever
used in the current function.
In df-scan.c, this is set up to record the hard regs used
explicitly. Reload adds in the hard regs used for holding pseudo
regs. Final uses it to generate the code in the function prologue
and epilogue to save and restore registers as needed. */
static bool regs_ever_live[FIRST_PSEUDO_REGISTER];
/* Flags used to tell df_refs_add_to_chains() which vectors it should copy. */
static const unsigned int copy_defs = 0x1;
static const unsigned int copy_uses = 0x2;
static const unsigned int copy_eq_uses = 0x4;
static const unsigned int copy_mw = 0x8;
static const unsigned int copy_all = copy_defs | copy_uses | copy_eq_uses
| copy_mw;
/*----------------------------------------------------------------------------
SCANNING DATAFLOW PROBLEM
There are several ways in which scanning looks just like the other
dataflow problems. It shares the all the mechanisms for local info
as well as basic block info. Where it differs is when and how often
it gets run. It also has no need for the iterative solver.
----------------------------------------------------------------------------*/
/* Problem data for the scanning dataflow function. */
struct df_scan_problem_data
{
object_allocator<df_base_ref> *ref_base_pool;
object_allocator<df_artificial_ref> *ref_artificial_pool;
object_allocator<df_regular_ref> *ref_regular_pool;
object_allocator<df_insn_info> *insn_pool;
object_allocator<df_reg_info> *reg_pool;
object_allocator<df_mw_hardreg> *mw_reg_pool;
bitmap_obstack reg_bitmaps;
bitmap_obstack insn_bitmaps;
};
/* Internal function to shut down the scanning problem. */
static void
df_scan_free_internal (void)
{
struct df_scan_problem_data *problem_data
= (struct df_scan_problem_data *) df_scan->problem_data;
free (df->def_info.refs);
free (df->def_info.begin);
free (df->def_info.count);
memset (&df->def_info, 0, (sizeof (struct df_ref_info)));
free (df->use_info.refs);
free (df->use_info.begin);
free (df->use_info.count);
memset (&df->use_info, 0, (sizeof (struct df_ref_info)));
free (df->def_regs);
df->def_regs = NULL;
free (df->use_regs);
df->use_regs = NULL;
free (df->eq_use_regs);
df->eq_use_regs = NULL;
df->regs_size = 0;
DF_REG_SIZE (df) = 0;
free (df->insns);
df->insns = NULL;
DF_INSN_SIZE () = 0;
free (df_scan->block_info);
df_scan->block_info = NULL;
df_scan->block_info_size = 0;
bitmap_clear (&df->hardware_regs_used);
bitmap_clear (&df->regular_block_artificial_uses);
bitmap_clear (&df->eh_block_artificial_uses);
BITMAP_FREE (df->entry_block_defs);
BITMAP_FREE (df->exit_block_uses);
bitmap_clear (&df->insns_to_delete);
bitmap_clear (&df->insns_to_rescan);
bitmap_clear (&df->insns_to_notes_rescan);
delete problem_data->ref_base_pool;
delete problem_data->ref_artificial_pool;
delete problem_data->ref_regular_pool;
delete problem_data->insn_pool;
delete problem_data->reg_pool;
delete problem_data->mw_reg_pool;
bitmap_obstack_release (&problem_data->reg_bitmaps);
bitmap_obstack_release (&problem_data->insn_bitmaps);
free (df_scan->problem_data);
}
/* Free basic block info. */
static void
df_scan_free_bb_info (basic_block bb, void *vbb_info)
{
struct df_scan_bb_info *bb_info = (struct df_scan_bb_info *) vbb_info;
unsigned int bb_index = bb->index;
rtx_insn *insn;
FOR_BB_INSNS (bb, insn)
if (INSN_P (insn))
df_insn_info_delete (INSN_UID (insn));
if (bb_index < df_scan->block_info_size)
bb_info = df_scan_get_bb_info (bb_index);
/* Get rid of any artificial uses or defs. */
df_ref_chain_delete_du_chain (bb_info->artificial_defs);
df_ref_chain_delete_du_chain (bb_info->artificial_uses);
df_ref_chain_delete (bb_info->artificial_defs);
df_ref_chain_delete (bb_info->artificial_uses);
bb_info->artificial_defs = NULL;
bb_info->artificial_uses = NULL;
}
/* Allocate the problem data for the scanning problem. This should be
called when the problem is created or when the entire function is to
be rescanned. */
void
df_scan_alloc (bitmap all_blocks ATTRIBUTE_UNUSED)
{
struct df_scan_problem_data *problem_data;
unsigned int insn_num = get_max_uid () + 1;
basic_block bb;
/* Given the number of pools, this is really faster than tearing
everything apart. */
if (df_scan->problem_data)
df_scan_free_internal ();
problem_data = XNEW (struct df_scan_problem_data);
df_scan->problem_data = problem_data;
df_scan->computed = true;
problem_data->ref_base_pool = new object_allocator<df_base_ref>
("df_scan ref base");
problem_data->ref_artificial_pool = new object_allocator<df_artificial_ref>
("df_scan ref artificial");
problem_data->ref_regular_pool = new object_allocator<df_regular_ref>
("df_scan ref regular");
problem_data->insn_pool = new object_allocator<df_insn_info>
("df_scan insn");
problem_data->reg_pool = new object_allocator<df_reg_info>
("df_scan reg");
problem_data->mw_reg_pool = new object_allocator<df_mw_hardreg>
("df_scan mw_reg");
bitmap_obstack_initialize (&problem_data->reg_bitmaps);
bitmap_obstack_initialize (&problem_data->insn_bitmaps);
insn_num += insn_num / 4;
df_grow_reg_info ();
df_grow_insn_info ();
df_grow_bb_info (df_scan);
FOR_ALL_BB_FN (bb, cfun)
{
unsigned int bb_index = bb->index;
struct df_scan_bb_info *bb_info = df_scan_get_bb_info (bb_index);
bb_info->artificial_defs = NULL;
bb_info->artificial_uses = NULL;
}
bitmap_initialize (&df->hardware_regs_used, &problem_data->reg_bitmaps);
bitmap_initialize (&df->regular_block_artificial_uses, &problem_data->reg_bitmaps);
bitmap_initialize (&df->eh_block_artificial_uses, &problem_data->reg_bitmaps);
df->entry_block_defs = BITMAP_ALLOC (&problem_data->reg_bitmaps);
df->exit_block_uses = BITMAP_ALLOC (&problem_data->reg_bitmaps);
bitmap_initialize (&df->insns_to_delete, &problem_data->insn_bitmaps);
bitmap_initialize (&df->insns_to_rescan, &problem_data->insn_bitmaps);
bitmap_initialize (&df->insns_to_notes_rescan, &problem_data->insn_bitmaps);
df_scan->optional_p = false;
}
/* Free all of the data associated with the scan problem. */
static void
df_scan_free (void)
{
if (df_scan->problem_data)
df_scan_free_internal ();
if (df->blocks_to_analyze)
{
BITMAP_FREE (df->blocks_to_analyze);
df->blocks_to_analyze = NULL;
}
free (df_scan);
}
/* Dump the preamble for DF_SCAN dump. */
static void
df_scan_start_dump (FILE *file ATTRIBUTE_UNUSED)
{
int i;
int dcount = 0;
int ucount = 0;
int ecount = 0;
int icount = 0;
int ccount = 0;
basic_block bb;
rtx_insn *insn;
fprintf (file, ";; invalidated by call \t");
df_print_regset (file, regs_invalidated_by_call_regset);
fprintf (file, ";; hardware regs used \t");
df_print_regset (file, &df->hardware_regs_used);
fprintf (file, ";; regular block artificial uses \t");
df_print_regset (file, &df->regular_block_artificial_uses);
fprintf (file, ";; eh block artificial uses \t");
df_print_regset (file, &df->eh_block_artificial_uses);
fprintf (file, ";; entry block defs \t");
df_print_regset (file, df->entry_block_defs);
fprintf (file, ";; exit block uses \t");
df_print_regset (file, df->exit_block_uses);
fprintf (file, ";; regs ever live \t");
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
if (df_regs_ever_live_p (i))
fprintf (file, " %d [%s]", i, reg_names[i]);
fprintf (file, "\n;; ref usage \t");
for (i = 0; i < (int)df->regs_inited; i++)
if (DF_REG_DEF_COUNT (i) || DF_REG_USE_COUNT (i) || DF_REG_EQ_USE_COUNT (i))
{
const char * sep = "";
fprintf (file, "r%d={", i);
if (DF_REG_DEF_COUNT (i))
{
fprintf (file, "%dd", DF_REG_DEF_COUNT (i));
sep = ",";
dcount += DF_REG_DEF_COUNT (i);
}
if (DF_REG_USE_COUNT (i))
{
fprintf (file, "%s%du", sep, DF_REG_USE_COUNT (i));
sep = ",";
ucount += DF_REG_USE_COUNT (i);
}
if (DF_REG_EQ_USE_COUNT (i))
{
fprintf (file, "%s%de", sep, DF_REG_EQ_USE_COUNT (i));
ecount += DF_REG_EQ_USE_COUNT (i);
}
fprintf (file, "} ");
}
FOR_EACH_BB_FN (bb, cfun)
FOR_BB_INSNS (bb, insn)
if (INSN_P (insn))
{
if (CALL_P (insn))
ccount++;
else
icount++;
}
fprintf (file, "\n;; total ref usage %d{%dd,%du,%de}"
" in %d{%d regular + %d call} insns.\n",
dcount + ucount + ecount, dcount, ucount, ecount,
icount + ccount, icount, ccount);
}
/* Dump the bb_info for a given basic block. */
static void
df_scan_start_block (basic_block bb, FILE *file)
{
struct df_scan_bb_info *bb_info
= df_scan_get_bb_info (bb->index);
if (bb_info)
{
fprintf (file, ";; bb %d artificial_defs: ", bb->index);
df_refs_chain_dump (bb_info->artificial_defs, true, file);
fprintf (file, "\n;; bb %d artificial_uses: ", bb->index);
df_refs_chain_dump (bb_info->artificial_uses, true, file);
fprintf (file, "\n");
}
#if 0
{
rtx_insn *insn;
FOR_BB_INSNS (bb, insn)
if (INSN_P (insn))
df_insn_debug (insn, false, file);
}
#endif
}
static const struct df_problem problem_SCAN =
{
DF_SCAN, /* Problem id. */
DF_NONE, /* Direction. */
df_scan_alloc, /* Allocate the problem specific data. */
NULL, /* Reset global information. */
df_scan_free_bb_info, /* Free basic block info. */
NULL, /* Local compute function. */
NULL, /* Init the solution specific data. */
NULL, /* Iterative solver. */
NULL, /* Confluence operator 0. */
NULL, /* Confluence operator n. */
NULL, /* Transfer function. */
NULL, /* Finalize function. */
df_scan_free, /* Free all of the problem information. */
NULL, /* Remove this problem from the stack of dataflow problems. */
df_scan_start_dump, /* Debugging. */
df_scan_start_block, /* Debugging start block. */
NULL, /* Debugging end block. */
NULL, /* Debugging start insn. */
NULL, /* Debugging end insn. */
NULL, /* Incremental solution verify start. */
NULL, /* Incremental solution verify end. */
NULL, /* Dependent problem. */
sizeof (struct df_scan_bb_info),/* Size of entry of block_info array. */
TV_DF_SCAN, /* Timing variable. */
false /* Reset blocks on dropping out of blocks_to_analyze. */
};
/* Create a new DATAFLOW instance and add it to an existing instance
of DF. The returned structure is what is used to get at the
solution. */
void
df_scan_add_problem (void)
{
df_add_problem (&problem_SCAN);
}
/*----------------------------------------------------------------------------
Storage Allocation Utilities
----------------------------------------------------------------------------*/
/* First, grow the reg_info information. If the current size is less than
the number of pseudos, grow to 25% more than the number of
pseudos.
Second, assure that all of the slots up to max_reg_num have been
filled with reg_info structures. */
void
df_grow_reg_info (void)
{
unsigned int max_reg = max_reg_num ();
unsigned int new_size = max_reg;
struct df_scan_problem_data *problem_data
= (struct df_scan_problem_data *) df_scan->problem_data;
unsigned int i;
if (df->regs_size < new_size)
{
new_size += new_size / 4;
df->def_regs = XRESIZEVEC (struct df_reg_info *, df->def_regs, new_size);
df->use_regs = XRESIZEVEC (struct df_reg_info *, df->use_regs, new_size);
df->eq_use_regs = XRESIZEVEC (struct df_reg_info *, df->eq_use_regs,
new_size);
df->def_info.begin = XRESIZEVEC (unsigned, df->def_info.begin, new_size);
df->def_info.count = XRESIZEVEC (unsigned, df->def_info.count, new_size);
df->use_info.begin = XRESIZEVEC (unsigned, df->use_info.begin, new_size);
df->use_info.count = XRESIZEVEC (unsigned, df->use_info.count, new_size);
df->regs_size = new_size;
}
for (i = df->regs_inited; i < max_reg; i++)
{
struct df_reg_info *reg_info;
// TODO
reg_info = problem_data->reg_pool->allocate ();
memset (reg_info, 0, sizeof (struct df_reg_info));
df->def_regs[i] = reg_info;
reg_info = problem_data->reg_pool->allocate ();
memset (reg_info, 0, sizeof (struct df_reg_info));
df->use_regs[i] = reg_info;
reg_info = problem_data->reg_pool->allocate ();
memset (reg_info, 0, sizeof (struct df_reg_info));
df->eq_use_regs[i] = reg_info;
df->def_info.begin[i] = 0;
df->def_info.count[i] = 0;
df->use_info.begin[i] = 0;
df->use_info.count[i] = 0;
}
df->regs_inited = max_reg;
}
/* Grow the ref information. */
static void
df_grow_ref_info (struct df_ref_info *ref_info, unsigned int new_size)
{
if (ref_info->refs_size < new_size)
{
ref_info->refs = XRESIZEVEC (df_ref, ref_info->refs, new_size);
memset (ref_info->refs + ref_info->refs_size, 0,
(new_size - ref_info->refs_size) *sizeof (df_ref));
ref_info->refs_size = new_size;
}
}
/* Check and grow the ref information if necessary. This routine
guarantees total_size + BITMAP_ADDEND amount of entries in refs
array. It updates ref_info->refs_size only and does not change
ref_info->total_size. */
static void
df_check_and_grow_ref_info (struct df_ref_info *ref_info,
unsigned bitmap_addend)
{
if (ref_info->refs_size < ref_info->total_size + bitmap_addend)
{
int new_size = ref_info->total_size + bitmap_addend;
new_size += ref_info->total_size / 4;
df_grow_ref_info (ref_info, new_size);
}
}
/* Grow the ref information. If the current size is less than the
number of instructions, grow to 25% more than the number of
instructions. */
void
df_grow_insn_info (void)
{
unsigned int new_size = get_max_uid () + 1;
if (DF_INSN_SIZE () < new_size)
{
new_size += new_size / 4;
df->insns = XRESIZEVEC (struct df_insn_info *, df->insns, new_size);
memset (df->insns + df->insns_size, 0,
(new_size - DF_INSN_SIZE ()) *sizeof (struct df_insn_info *));
DF_INSN_SIZE () = new_size;
}
}
/*----------------------------------------------------------------------------
PUBLIC INTERFACES FOR SMALL GRAIN CHANGES TO SCANNING.
----------------------------------------------------------------------------*/
/* Rescan all of the block_to_analyze or all of the blocks in the
function if df_set_blocks if blocks_to_analyze is NULL; */
void
df_scan_blocks (void)
{
basic_block bb;
df->def_info.ref_order = DF_REF_ORDER_NO_TABLE;
df->use_info.ref_order = DF_REF_ORDER_NO_TABLE;
df_get_regular_block_artificial_uses (&df->regular_block_artificial_uses);
df_get_eh_block_artificial_uses (&df->eh_block_artificial_uses);
bitmap_ior_into (&df->eh_block_artificial_uses,
&df->regular_block_artificial_uses);
/* ENTRY and EXIT blocks have special defs/uses. */
df_get_entry_block_def_set (df->entry_block_defs);
df_record_entry_block_defs (df->entry_block_defs);
df_get_exit_block_use_set (df->exit_block_uses);
df_record_exit_block_uses (df->exit_block_uses);
df_set_bb_dirty (BASIC_BLOCK_FOR_FN (cfun, ENTRY_BLOCK));
df_set_bb_dirty (BASIC_BLOCK_FOR_FN (cfun, EXIT_BLOCK));
/* Regular blocks */
FOR_EACH_BB_FN (bb, cfun)
{
unsigned int bb_index = bb->index;
df_bb_refs_record (bb_index, true);
}
}
/* Create new refs under address LOC within INSN. This function is
only used externally. REF_FLAGS must be either 0 or DF_REF_IN_NOTE,
depending on whether LOC is inside PATTERN (INSN) or a note. */
void
df_uses_create (rtx *loc, rtx_insn *insn, int ref_flags)
{
gcc_assert (!(ref_flags & ~DF_REF_IN_NOTE));
df_uses_record (NULL, loc, DF_REF_REG_USE,
BLOCK_FOR_INSN (insn),
DF_INSN_INFO_GET (insn),
ref_flags);
}
static void
df_install_ref_incremental (df_ref ref)
{
struct df_reg_info **reg_info;
struct df_ref_info *ref_info;
df_ref *ref_ptr;
bool add_to_table;
rtx_insn *insn = DF_REF_INSN (ref);
basic_block bb = BLOCK_FOR_INSN (insn);
if (DF_REF_REG_DEF_P (ref))
{
reg_info = df->def_regs;
ref_info = &df->def_info;
ref_ptr = &DF_INSN_DEFS (insn);
add_to_table = ref_info->ref_order != DF_REF_ORDER_NO_TABLE;
}
else if (DF_REF_FLAGS (ref) & DF_REF_IN_NOTE)
{
reg_info = df->eq_use_regs;
ref_info = &df->use_info;
ref_ptr = &DF_INSN_EQ_USES (insn);
switch (ref_info->ref_order)
{
case DF_REF_ORDER_UNORDERED_WITH_NOTES:
case DF_REF_ORDER_BY_REG_WITH_NOTES:
case DF_REF_ORDER_BY_INSN_WITH_NOTES:
add_to_table = true;
break;
default:
add_to_table = false;
break;
}
}
else
{
reg_info = df->use_regs;
ref_info = &df->use_info;
ref_ptr = &DF_INSN_USES (insn);
add_to_table = ref_info->ref_order != DF_REF_ORDER_NO_TABLE;
}
/* Do not add if ref is not in the right blocks. */
if (add_to_table && df->analyze_subset)
add_to_table = bitmap_bit_p (df->blocks_to_analyze, bb->index);
df_install_ref (ref, reg_info[DF_REF_REGNO (ref)], ref_info, add_to_table);
if (add_to_table)
switch (ref_info->ref_order)
{
case DF_REF_ORDER_UNORDERED_WITH_NOTES:
case DF_REF_ORDER_BY_REG_WITH_NOTES:
case DF_REF_ORDER_BY_INSN_WITH_NOTES:
ref_info->ref_order = DF_REF_ORDER_UNORDERED_WITH_NOTES;
break;
default:
ref_info->ref_order = DF_REF_ORDER_UNORDERED;
break;
}
while (*ref_ptr && df_ref_compare (*ref_ptr, ref) < 0)
ref_ptr = &DF_REF_NEXT_LOC (*ref_ptr);
DF_REF_NEXT_LOC (ref) = *ref_ptr;
*ref_ptr = ref;
#if 0
if (dump_file)
{
fprintf (dump_file, "adding ref ");
df_ref_debug (ref, dump_file);
}
#endif
/* By adding the ref directly, df_insn_rescan my not find any
differences even though the block will have changed. So we need
to mark the block dirty ourselves. */
if (!DEBUG_INSN_P (DF_REF_INSN (ref)))
df_set_bb_dirty (bb);
}
/*----------------------------------------------------------------------------
UTILITIES TO CREATE AND DESTROY REFS AND CHAINS.
----------------------------------------------------------------------------*/
static void
df_free_ref (df_ref ref)
{
struct df_scan_problem_data *problem_data
= (struct df_scan_problem_data *) df_scan->problem_data;
switch (DF_REF_CLASS (ref))
{
case DF_REF_BASE:
problem_data->ref_base_pool->remove ((df_base_ref *) (ref));
break;
case DF_REF_ARTIFICIAL:
problem_data->ref_artificial_pool->remove
((df_artificial_ref *) (ref));
break;
case DF_REF_REGULAR:
problem_data->ref_regular_pool->remove
((df_regular_ref *) (ref));
break;
}
}
/* Unlink and delete REF at the reg_use, reg_eq_use or reg_def chain.
Also delete the def-use or use-def chain if it exists. */
static void
df_reg_chain_unlink (df_ref ref)
{
df_ref next = DF_REF_NEXT_REG (ref);
df_ref prev = DF_REF_PREV_REG (ref);
int id = DF_REF_ID (ref);
struct df_reg_info *reg_info;
df_ref *refs = NULL;
if (DF_REF_REG_DEF_P (ref))
{
int regno = DF_REF_REGNO (ref);
reg_info = DF_REG_DEF_GET (regno);
refs = df->def_info.refs;
}
else
{
if (DF_REF_FLAGS (ref) & DF_REF_IN_NOTE)
{
reg_info = DF_REG_EQ_USE_GET (DF_REF_REGNO (ref));
switch (df->use_info.ref_order)
{
case DF_REF_ORDER_UNORDERED_WITH_NOTES:
case DF_REF_ORDER_BY_REG_WITH_NOTES:
case DF_REF_ORDER_BY_INSN_WITH_NOTES:
refs = df->use_info.refs;
break;
default:
break;
}
}
else
{
reg_info = DF_REG_USE_GET (DF_REF_REGNO (ref));
refs = df->use_info.refs;
}
}
if (refs)
{
if (df->analyze_subset)
{
if (bitmap_bit_p (df->blocks_to_analyze, DF_REF_BBNO (ref)))
refs[id] = NULL;
}
else
refs[id] = NULL;
}
/* Delete any def-use or use-def chains that start here. It is
possible that there is trash in this field. This happens for
insns that have been deleted when rescanning has been deferred
and the chain problem has also been deleted. The chain tear down
code skips deleted insns. */
if (df_chain && DF_REF_CHAIN (ref))
df_chain_unlink (ref);
reg_info->n_refs--;
if (DF_REF_FLAGS_IS_SET (ref, DF_HARD_REG_LIVE))
{
gcc_assert (DF_REF_REGNO (ref) < FIRST_PSEUDO_REGISTER);
df->hard_regs_live_count[DF_REF_REGNO (ref)]--;
}
/* Unlink from the reg chain. If there is no prev, this is the
first of the list. If not, just join the next and prev. */
if (prev)
DF_REF_NEXT_REG (prev) = next;
else
{
gcc_assert (reg_info->reg_chain == ref);
reg_info->reg_chain = next;
}
if (next)
DF_REF_PREV_REG (next) = prev;
df_free_ref (ref);
}
/* Initialize INSN_INFO to describe INSN. */
static void
df_insn_info_init_fields (df_insn_info *insn_info, rtx_insn *insn)
{
memset (insn_info, 0, sizeof (struct df_insn_info));
insn_info->insn = insn;
}
/* Create the insn record for INSN. If there was one there, zero it
out. */
struct df_insn_info *
df_insn_create_insn_record (rtx_insn *insn)
{
struct df_scan_problem_data *problem_data
= (struct df_scan_problem_data *) df_scan->problem_data;
struct df_insn_info *insn_rec;
df_grow_insn_info ();
insn_rec = DF_INSN_INFO_GET (insn);
if (!insn_rec)
{
insn_rec = problem_data->insn_pool->allocate ();
DF_INSN_INFO_SET (insn, insn_rec);
}
df_insn_info_init_fields (insn_rec, insn);
return insn_rec;
}
/* Delete all du chain (DF_REF_CHAIN()) of all refs in the ref chain. */
static void
df_ref_chain_delete_du_chain (df_ref ref)
{
for (; ref; ref = DF_REF_NEXT_LOC (ref))
/* CHAIN is allocated by DF_CHAIN. So make sure to
pass df_scan instance for the problem. */
if (DF_REF_CHAIN (ref))
df_chain_unlink (ref);
}
/* Delete all refs in the ref chain. */
static void
df_ref_chain_delete (df_ref ref)
{
df_ref next;
for (; ref; ref = next)
{
next = DF_REF_NEXT_LOC (ref);
df_reg_chain_unlink (ref);
}
}
/* Delete the hardreg chain. */
static void
df_mw_hardreg_chain_delete (struct df_mw_hardreg *hardregs)
{
struct df_scan_problem_data *problem_data
= (struct df_scan_problem_data *) df_scan->problem_data;
df_mw_hardreg *next;
for (; hardregs; hardregs = next)
{
next = DF_MWS_NEXT (hardregs);
problem_data->mw_reg_pool->remove (hardregs);
}
}
/* Remove the contents of INSN_INFO (but don't free INSN_INFO itself). */
static void
df_insn_info_free_fields (df_insn_info *insn_info)
{
/* In general, notes do not have the insn_info fields
initialized. However, combine deletes insns by changing them
to notes. How clever. So we cannot just check if it is a
valid insn before short circuiting this code, we need to see
if we actually initialized it. */
df_mw_hardreg_chain_delete (insn_info->mw_hardregs);
if (df_chain)
{
df_ref_chain_delete_du_chain (insn_info->defs);
df_ref_chain_delete_du_chain (insn_info->uses);
df_ref_chain_delete_du_chain (insn_info->eq_uses);
}
df_ref_chain_delete (insn_info->defs);
df_ref_chain_delete (insn_info->uses);
df_ref_chain_delete (insn_info->eq_uses);
}
/* Delete all of the refs information from the insn with UID.
Internal helper for df_insn_delete, df_insn_rescan, and other
df-scan routines that don't have to work in deferred mode
and do not have to mark basic blocks for re-processing. */
static void
df_insn_info_delete (unsigned int uid)
{
struct df_insn_info *insn_info = DF_INSN_UID_SAFE_GET (uid);
bitmap_clear_bit (&df->insns_to_delete, uid);
bitmap_clear_bit (&df->insns_to_rescan, uid);
bitmap_clear_bit (&df->insns_to_notes_rescan, uid);
if (insn_info)
{
struct df_scan_problem_data *problem_data
= (struct df_scan_problem_data *) df_scan->problem_data;
df_insn_info_free_fields (insn_info);
problem_data->insn_pool->remove (insn_info);
DF_INSN_UID_SET (uid, NULL);
}
}
/* Delete all of the refs information from INSN, either right now
or marked for later in deferred mode. */
void
df_insn_delete (rtx_insn *insn)
{
unsigned int uid;
basic_block bb;
gcc_checking_assert (INSN_P (insn));
if (!df)
return;
uid = INSN_UID (insn);
bb = BLOCK_FOR_INSN (insn);
/* ??? bb can be NULL after pass_free_cfg. At that point, DF should
not exist anymore (as mentioned in df-core.c: "The only requirement
[for DF] is that there be a correct control flow graph." Clearly
that isn't the case after pass_free_cfg. But DF is freed much later
because some back-ends want to use DF info even though the CFG is
already gone. It's not clear to me whether that is safe, actually.
In any case, we expect BB to be non-NULL at least up to register
allocation, so disallow a non-NULL BB up to there. Not perfect
but better than nothing... */
gcc_checking_assert (bb != NULL || reload_completed);
df_grow_bb_info (df_scan);
df_grow_reg_info ();
/* The block must be marked as dirty now, rather than later as in
df_insn_rescan and df_notes_rescan because it may not be there at
rescanning time and the mark would blow up.
DEBUG_INSNs do not make a block's data flow solution dirty (at
worst the LUIDs are no longer contiguous). */
if (bb != NULL && NONDEBUG_INSN_P (insn))
df_set_bb_dirty (bb);
/* The client has deferred rescanning. */
if (df->changeable_flags & DF_DEFER_INSN_RESCAN)
{
struct df_insn_info *insn_info = DF_INSN_UID_SAFE_GET (uid);
if (insn_info)
{
bitmap_clear_bit (&df->insns_to_rescan, uid);
bitmap_clear_bit (&df->insns_to_notes_rescan, uid);
bitmap_set_bit (&df->insns_to_delete, uid);
}
if (dump_file)
fprintf (dump_file, "deferring deletion of insn with uid = %d.\n", uid);
return;
}
if (dump_file)
fprintf (dump_file, "deleting insn with uid = %d.\n", uid);
df_insn_info_delete (uid);
}
/* Free all of the refs and the mw_hardregs in COLLECTION_REC. */
static void
df_free_collection_rec (struct df_collection_rec *collection_rec)
{
unsigned int ix;
struct df_scan_problem_data *problem_data
= (struct df_scan_problem_data *) df_scan->problem_data;
df_ref ref;
struct df_mw_hardreg *mw;
FOR_EACH_VEC_ELT (collection_rec->def_vec, ix, ref)
df_free_ref (ref);
FOR_EACH_VEC_ELT (collection_rec->use_vec, ix, ref)
df_free_ref (ref);
FOR_EACH_VEC_ELT (collection_rec->eq_use_vec, ix, ref)
df_free_ref (ref);
FOR_EACH_VEC_ELT (collection_rec->mw_vec, ix, mw)
problem_data->mw_reg_pool->remove (mw);
collection_rec->def_vec.release ();
collection_rec->use_vec.release ();
collection_rec->eq_use_vec.release ();
collection_rec->mw_vec.release ();
}
/* Rescan INSN. Return TRUE if the rescanning produced any changes. */
bool
df_insn_rescan (rtx_insn *insn)
{
unsigned int uid = INSN_UID (insn);
struct df_insn_info *insn_info = NULL;
basic_block bb = BLOCK_FOR_INSN (insn);
struct df_collection_rec collection_rec;
if ((!df) || (!INSN_P (insn)))
return false;
if (!bb)
{
if (dump_file)
fprintf (dump_file, "no bb for insn with uid = %d.\n", uid);
return false;
}
/* The client has disabled rescanning and plans to do it itself. */
if (df->changeable_flags & DF_NO_INSN_RESCAN)
return false;
df_grow_bb_info (df_scan);
df_grow_reg_info ();
insn_info = DF_INSN_UID_SAFE_GET (uid);
/* The client has deferred rescanning. */
if (df->changeable_flags & DF_DEFER_INSN_RESCAN)
{
if (!insn_info)
{
insn_info = df_insn_create_insn_record (insn);
insn_info->defs = 0;
insn_info->uses = 0;
insn_info->eq_uses = 0;
insn_info->mw_hardregs = 0;
}
if (dump_file)
fprintf (dump_file, "deferring rescan insn with uid = %d.\n", uid);
bitmap_clear_bit (&df->insns_to_delete, uid);
bitmap_clear_bit (&df->insns_to_notes_rescan, uid);
bitmap_set_bit (&df->insns_to_rescan, INSN_UID (insn));
return false;
}
bitmap_clear_bit (&df->insns_to_delete, uid);
bitmap_clear_bit (&df->insns_to_rescan, uid);
bitmap_clear_bit (&df->insns_to_notes_rescan, uid);
if (insn_info)
{
int luid;
bool the_same = df_insn_refs_verify (&collection_rec, bb, insn, false);
/* If there's no change, return false. */
if (the_same)
{
df_free_collection_rec (&collection_rec);
if (dump_file)
fprintf (dump_file, "verify found no changes in insn with uid = %d.\n", uid);
return false;
}
if (dump_file)
fprintf (dump_file, "rescanning insn with uid = %d.\n", uid);
/* There's change - we need to delete the existing info.
Since the insn isn't moved, we can salvage its LUID. */
luid = DF_INSN_LUID (insn);
df_insn_info_free_fields (insn_info);
df_insn_info_init_fields (insn_info, insn);
DF_INSN_LUID (insn) = luid;
}
else
{
struct df_insn_info *insn_info = df_insn_create_insn_record (insn);
df_insn_refs_collect (&collection_rec, bb, insn_info);
if (dump_file)
fprintf (dump_file, "scanning new insn with uid = %d.\n", uid);
}
df_refs_add_to_chains (&collection_rec, bb, insn, copy_all);
if (!DEBUG_INSN_P (insn))
df_set_bb_dirty (bb);
return true;
}
/* Same as df_insn_rescan, but don't mark the basic block as
dirty. */
bool
df_insn_rescan_debug_internal (rtx_insn *insn)
{
unsigned int uid = INSN_UID (insn);
struct df_insn_info *insn_info;
gcc_assert (DEBUG_INSN_P (insn)
&& VAR_LOC_UNKNOWN_P (INSN_VAR_LOCATION_LOC (insn)));
if (!df)
return false;
insn_info = DF_INSN_UID_SAFE_GET (INSN_UID (insn));
if (!insn_info)
return false;
if (dump_file)
fprintf (dump_file, "deleting debug_insn with uid = %d.\n", uid);
bitmap_clear_bit (&df->insns_to_delete, uid);
bitmap_clear_bit (&df->insns_to_rescan, uid);
bitmap_clear_bit (&df->insns_to_notes_rescan, uid);
if (insn_info->defs == 0
&& insn_info->uses == 0
&& insn_info->eq_uses == 0
&& insn_info->mw_hardregs == 0)
return false;
df_mw_hardreg_chain_delete (insn_info->mw_hardregs);
if (df_chain)
{
df_ref_chain_delete_du_chain (insn_info->defs);
df_ref_chain_delete_du_chain (insn_info->uses);
df_ref_chain_delete_du_chain (insn_info->eq_uses);
}
df_ref_chain_delete (insn_info->defs);
df_ref_chain_delete (insn_info->uses);
df_ref_chain_delete (insn_info->eq_uses);
insn_info->defs = 0;
insn_info->uses = 0;
insn_info->eq_uses = 0;
insn_info->mw_hardregs = 0;
return true;
}
/* Rescan all of the insns in the function. Note that the artificial
uses and defs are not touched. This function will destroy def-use
or use-def chains. */
void
df_insn_rescan_all (void)
{
bool no_insn_rescan = false;
bool defer_insn_rescan = false;
basic_block bb;
bitmap_iterator bi;
unsigned int uid;
bitmap_head tmp;
bitmap_initialize (&tmp, &df_bitmap_obstack);
if (df->changeable_flags & DF_NO_INSN_RESCAN)
{
df_clear_flags (DF_NO_INSN_RESCAN);
no_insn_rescan = true;
}
if (df->changeable_flags & DF_DEFER_INSN_RESCAN)
{
df_clear_flags (DF_DEFER_INSN_RESCAN);
defer_insn_rescan = true;
}
bitmap_copy (&tmp, &df->insns_to_delete);
EXECUTE_IF_SET_IN_BITMAP (&tmp, 0, uid, bi)
{
struct df_insn_info *insn_info = DF_INSN_UID_SAFE_GET (uid);
if (insn_info)
df_insn_info_delete (uid);
}
bitmap_clear (&tmp);
bitmap_clear (&df->insns_to_delete);
bitmap_clear (&df->insns_to_rescan);
bitmap_clear (&df->insns_to_notes_rescan);
FOR_EACH_BB_FN (bb, cfun)
{
rtx_insn *insn;
FOR_BB_INSNS (bb, insn)
{
df_insn_rescan (insn);
}
}
if (no_insn_rescan)
df_set_flags (DF_NO_INSN_RESCAN);
if (defer_insn_rescan)
df_set_flags (DF_DEFER_INSN_RESCAN);
}
/* Process all of the deferred rescans or deletions. */
void
df_process_deferred_rescans (void)
{
bool no_insn_rescan = false;
bool defer_insn_rescan = false;
bitmap_iterator bi;
unsigned int uid;
bitmap_head tmp;
bitmap_initialize (&tmp, &df_bitmap_obstack);
if (df->changeable_flags & DF_NO_INSN_RESCAN)
{
df_clear_flags (DF_NO_INSN_RESCAN);
no_insn_rescan = true;
}
if (df->changeable_flags & DF_DEFER_INSN_RESCAN)
{
df_clear_flags (DF_DEFER_INSN_RESCAN);
defer_insn_rescan = true;
}
if (dump_file)
fprintf (dump_file, "starting the processing of deferred insns\n");
bitmap_copy (&tmp, &df->insns_to_delete);
EXECUTE_IF_SET_IN_BITMAP (&tmp, 0, uid, bi)
{
struct df_insn_info *insn_info = DF_INSN_UID_SAFE_GET (uid);
if (insn_info)
df_insn_info_delete (uid);
}
bitmap_copy (&tmp, &df->insns_to_rescan);
EXECUTE_IF_SET_IN_BITMAP (&tmp, 0, uid, bi)
{
struct df_insn_info *insn_info = DF_INSN_UID_SAFE_GET (uid);
if (insn_info)
df_insn_rescan (insn_info->insn);
}
bitmap_copy (&tmp, &df->insns_to_notes_rescan);
EXECUTE_IF_SET_IN_BITMAP (&tmp, 0, uid, bi)
{
struct df_insn_info *insn_info = DF_INSN_UID_SAFE_GET (uid);
if (insn_info)
df_notes_rescan (insn_info->insn);
}
if (dump_file)
fprintf (dump_file, "ending the processing of deferred insns\n");
bitmap_clear (&tmp);
bitmap_clear (&df->insns_to_delete);
bitmap_clear (&df->insns_to_rescan);
bitmap_clear (&df->insns_to_notes_rescan);
if (no_insn_rescan)
df_set_flags (DF_NO_INSN_RESCAN);
if (defer_insn_rescan)
df_set_flags (DF_DEFER_INSN_RESCAN);
/* If someone changed regs_ever_live during this pass, fix up the
entry and exit blocks. */
if (df->redo_entry_and_exit)
{
df_update_entry_exit_and_calls ();
df->redo_entry_and_exit = false;
}
}
/* Count the number of refs. Include the defs if INCLUDE_DEFS. Include
the uses if INCLUDE_USES. Include the eq_uses if
INCLUDE_EQ_USES. */
static unsigned int
df_count_refs (bool include_defs, bool include_uses,
bool include_eq_uses)
{
unsigned int regno;
int size = 0;
unsigned int m = df->regs_inited;
for (regno = 0; regno < m; regno++)
{
if (include_defs)
size += DF_REG_DEF_COUNT (regno);
if (include_uses)
size += DF_REG_USE_COUNT (regno);
if (include_eq_uses)
size += DF_REG_EQ_USE_COUNT (regno);
}
return size;
}
/* Take build ref table for either the uses or defs from the reg-use
or reg-def chains. This version processes the refs in reg order
which is likely to be best if processing the whole function. */
static void
df_reorganize_refs_by_reg_by_reg (struct df_ref_info *ref_info,
bool include_defs,
bool include_uses,
bool include_eq_uses)
{
unsigned int m = df->regs_inited;
unsigned int regno;
unsigned int offset = 0;
unsigned int start;
if (df->changeable_flags & DF_NO_HARD_REGS)
{
start = FIRST_PSEUDO_REGISTER;
memset (ref_info->begin, 0, sizeof (int) * FIRST_PSEUDO_REGISTER);
memset (ref_info->count, 0, sizeof (int) * FIRST_PSEUDO_REGISTER);
}
else
start = 0;
ref_info->total_size
= df_count_refs (include_defs, include_uses, include_eq_uses);
df_check_and_grow_ref_info (ref_info, 1);
for (regno = start; regno < m; regno++)
{
int count = 0;
ref_info->begin[regno] = offset;
if (include_defs)
{
df_ref ref = DF_REG_DEF_CHAIN (regno);
while (ref)
{
ref_info->refs[offset] = ref;
DF_REF_ID (ref) = offset++;
count++;
ref = DF_REF_NEXT_REG (ref);
gcc_checking_assert (offset < ref_info->refs_size);
}
}
if (include_uses)
{
df_ref ref = DF_REG_USE_CHAIN (regno);
while (ref)
{
ref_info->refs[offset] = ref;
DF_REF_ID (ref) = offset++;
count++;
ref = DF_REF_NEXT_REG (ref);
gcc_checking_assert (offset < ref_info->refs_size);
}
}
if (include_eq_uses)
{
df_ref ref = DF_REG_EQ_USE_CHAIN (regno);
while (ref)
{
ref_info->refs[offset] = ref;
DF_REF_ID (ref) = offset++;
count++;
ref = DF_REF_NEXT_REG (ref);
gcc_checking_assert (offset < ref_info->refs_size);
}
}
ref_info->count[regno] = count;
}
/* The bitmap size is not decremented when refs are deleted. So
reset it now that we have squished out all of the empty
slots. */
ref_info->table_size = offset;
}
/* Take build ref table for either the uses or defs from the reg-use
or reg-def chains. This version processes the refs in insn order
which is likely to be best if processing some segment of the
function. */
static void
df_reorganize_refs_by_reg_by_insn (struct df_ref_info *ref_info,
bool include_defs,
bool include_uses,
bool include_eq_uses)
{
bitmap_iterator bi;
unsigned int bb_index;
unsigned int m = df->regs_inited;
unsigned int offset = 0;
unsigned int r;
unsigned int start
= (df->changeable_flags & DF_NO_HARD_REGS) ? FIRST_PSEUDO_REGISTER : 0;
memset (ref_info->begin, 0, sizeof (int) * df->regs_inited);
memset (ref_info->count, 0, sizeof (int) * df->regs_inited);
ref_info->total_size = df_count_refs (include_defs, include_uses, include_eq_uses);
df_check_and_grow_ref_info (ref_info, 1);
EXECUTE_IF_SET_IN_BITMAP (df->blocks_to_analyze, 0, bb_index, bi)
{
basic_block bb = BASIC_BLOCK_FOR_FN (cfun, bb_index);
rtx_insn *insn;
df_ref def, use;
if (include_defs)
FOR_EACH_ARTIFICIAL_DEF (def, bb_index)
{
unsigned int regno = DF_REF_REGNO (def);
ref_info->count[regno]++;
}
if (include_uses)
FOR_EACH_ARTIFICIAL_USE (use, bb_index)
{
unsigned int regno = DF_REF_REGNO (use);
ref_info->count[regno]++;
}
FOR_BB_INSNS (bb, insn)
{
if (INSN_P (insn))
{
struct df_insn_info *insn_info = DF_INSN_INFO_GET (insn);
if (include_defs)
FOR_EACH_INSN_INFO_DEF (def, insn_info)
{
unsigned int regno = DF_REF_REGNO (def);
ref_info->count[regno]++;
}
if (include_uses)
FOR_EACH_INSN_INFO_USE (use, insn_info)
{
unsigned int regno = DF_REF_REGNO (use);
ref_info->count[regno]++;
}
if (include_eq_uses)
FOR_EACH_INSN_INFO_EQ_USE (use, insn_info)
{
unsigned int regno = DF_REF_REGNO (use);
ref_info->count[regno]++;
}
}
}
}
for (r = start; r < m; r++)
{
ref_info->begin[r] = offset;
offset += ref_info->count[r];
ref_info->count[r] = 0;
}
EXECUTE_IF_SET_IN_BITMAP (df->blocks_to_analyze, 0, bb_index, bi)
{
basic_block bb = BASIC_BLOCK_FOR_FN (cfun, bb_index);
rtx_insn *insn;
df_ref def, use;
if (include_defs)
FOR_EACH_ARTIFICIAL_DEF (def, bb_index)
{
unsigned int regno = DF_REF_REGNO (def);
if (regno >= start)
{
unsigned int id
= ref_info->begin[regno] + ref_info->count[regno]++;
DF_REF_ID (def) = id;
ref_info->refs[id] = def;
}
}
if (include_uses)
FOR_EACH_ARTIFICIAL_USE (use, bb_index)
{
unsigned int regno = DF_REF_REGNO (def);
if (regno >= start)
{
unsigned int id
= ref_info->begin[regno] + ref_info->count[regno]++;
DF_REF_ID (use) = id;
ref_info->refs[id] = use;
}
}
FOR_BB_INSNS (bb, insn)
{
if (INSN_P (insn))
{
struct df_insn_info *insn_info = DF_INSN_INFO_GET (insn);
if (include_defs)
FOR_EACH_INSN_INFO_DEF (def, insn_info)
{
unsigned int regno = DF_REF_REGNO (def);
if (regno >= start)
{
unsigned int id
= ref_info->begin[regno] + ref_info->count[regno]++;
DF_REF_ID (def) = id;
ref_info->refs[id] = def;
}
}
if (include_uses)
FOR_EACH_INSN_INFO_USE (use, insn_info)
{
unsigned int regno = DF_REF_REGNO (use);
if (regno >= start)
{
unsigned int id
= ref_info->begin[regno] + ref_info->count[regno]++;
DF_REF_ID (use) = id;
ref_info->refs[id] = use;
}
}
if (include_eq_uses)
FOR_EACH_INSN_INFO_EQ_USE (use, insn_info)
{
unsigned int regno = DF_REF_REGNO (use);
if (regno >= start)
{
unsigned int id
= ref_info->begin[regno] + ref_info->count[regno]++;
DF_REF_ID (use) = id;
ref_info->refs[id] = use;
}
}
}
}
}
/* The bitmap size is not decremented when refs are deleted. So
reset it now that we have squished out all of the empty
slots. */
ref_info->table_size = offset;
}
/* Take build ref table for either the uses or defs from the reg-use
or reg-def chains. */
static void
df_reorganize_refs_by_reg (struct df_ref_info *ref_info,
bool include_defs,
bool include_uses,
bool include_eq_uses)
{
if (df->analyze_subset)
df_reorganize_refs_by_reg_by_insn (ref_info, include_defs,
include_uses, include_eq_uses);
else
df_reorganize_refs_by_reg_by_reg (ref_info, include_defs,
include_uses, include_eq_uses);
}
/* Add the refs in REF_VEC to the table in REF_INFO starting at OFFSET. */
static unsigned int
df_add_refs_to_table (unsigned int offset,
struct df_ref_info *ref_info,
df_ref ref)
{
for (; ref; ref = DF_REF_NEXT_LOC (ref))
if (!(df->changeable_flags & DF_NO_HARD_REGS)
|| (DF_REF_REGNO (ref) >= FIRST_PSEUDO_REGISTER))
{
ref_info->refs[offset] = ref;
DF_REF_ID (ref) = offset++;
}
return offset;
}
/* Count the number of refs in all of the insns of BB. Include the
defs if INCLUDE_DEFS. Include the uses if INCLUDE_USES. Include the
eq_uses if INCLUDE_EQ_USES. */
static unsigned int
df_reorganize_refs_by_insn_bb (basic_block bb, unsigned int offset,
struct df_ref_info *ref_info,
bool include_defs, bool include_uses,
bool include_eq_uses)
{
rtx_insn *insn;
if (include_defs)
offset = df_add_refs_to_table (offset, ref_info,
df_get_artificial_defs (bb->index));
if (include_uses)
offset = df_add_refs_to_table (offset, ref_info,
df_get_artificial_uses (bb->index));
FOR_BB_INSNS (bb, insn)
if (INSN_P (insn))
{
unsigned int uid = INSN_UID (insn);
if (include_defs)
offset = df_add_refs_to_table (offset, ref_info,
DF_INSN_UID_DEFS (uid));
if (include_uses)
offset = df_add_refs_to_table (offset, ref_info,
DF_INSN_UID_USES (uid));
if (include_eq_uses)
offset = df_add_refs_to_table (offset, ref_info,
DF_INSN_UID_EQ_USES (uid));
}
return offset;
}
/* Organize the refs by insn into the table in REF_INFO. If
blocks_to_analyze is defined, use that set, otherwise the entire
program. Include the defs if INCLUDE_DEFS. Include the uses if
INCLUDE_USES. Include the eq_uses if INCLUDE_EQ_USES. */
static void
df_reorganize_refs_by_insn (struct df_ref_info *ref_info,
bool include_defs, bool include_uses,
bool include_eq_uses)
{
basic_block bb;
unsigned int offset = 0;
ref_info->total_size = df_count_refs (include_defs, include_uses, include_eq_uses);
df_check_and_grow_ref_info (ref_info, 1);
if (df->blocks_to_analyze)
{
bitmap_iterator bi;
unsigned int index;
EXECUTE_IF_SET_IN_BITMAP (df->blocks_to_analyze, 0, index, bi)
{
offset = df_reorganize_refs_by_insn_bb (BASIC_BLOCK_FOR_FN (cfun,
index),
offset, ref_info,
include_defs, include_uses,
include_eq_uses);
}
ref_info->table_size = offset;
}
else
{
FOR_ALL_BB_FN (bb, cfun)
offset = df_reorganize_refs_by_insn_bb (bb, offset, ref_info,
include_defs, include_uses,
include_eq_uses);
ref_info->table_size = offset;
}
}
/* If the use refs in DF are not organized, reorganize them. */
void
df_maybe_reorganize_use_refs (enum df_ref_order order)
{
if (order == df->use_info.ref_order)
return;
switch (order)
{
case DF_REF_ORDER_BY_REG:
df_reorganize_refs_by_reg (&df->use_info, false, true, false);
break;
case DF_REF_ORDER_BY_REG_WITH_NOTES:
df_reorganize_refs_by_reg (&df->use_info, false, true, true);
break;
case DF_REF_ORDER_BY_INSN:
df_reorganize_refs_by_insn (&df->use_info, false, true, false);
break;
case DF_REF_ORDER_BY_INSN_WITH_NOTES:
df_reorganize_refs_by_insn (&df->use_info, false, true, true);
break;
case DF_REF_ORDER_NO_TABLE:
free (df->use_info.refs);
df->use_info.refs = NULL;
df->use_info.refs_size = 0;
break;
case DF_REF_ORDER_UNORDERED:
case DF_REF_ORDER_UNORDERED_WITH_NOTES:
gcc_unreachable ();
break;
}
df->use_info.ref_order = order;
}
/* If the def refs in DF are not organized, reorganize them. */
void
df_maybe_reorganize_def_refs (enum df_ref_order order)
{
if (order == df->def_info.ref_order)
return;
switch (order)
{
case DF_REF_ORDER_BY_REG:
df_reorganize_refs_by_reg (&df->def_info, true, false, false);
break;
case DF_REF_ORDER_BY_INSN:
df_reorganize_refs_by_insn (&df->def_info, true, false, false);
break;
case DF_REF_ORDER_NO_TABLE:
free (df->def_info.refs);
df->def_info.refs = NULL;
df->def_info.refs_size = 0;
break;
case DF_REF_ORDER_BY_INSN_WITH_NOTES:
case DF_REF_ORDER_BY_REG_WITH_NOTES:
case DF_REF_ORDER_UNORDERED:
case DF_REF_ORDER_UNORDERED_WITH_NOTES:
gcc_unreachable ();
break;
}
df->def_info.ref_order = order;
}
/* Change all of the basic block references in INSN to use the insn's
current basic block. This function is called from routines that move
instructions from one block to another. */
void
df_insn_change_bb (rtx_insn *insn, basic_block new_bb)
{
basic_block old_bb = BLOCK_FOR_INSN (insn);
struct df_insn_info *insn_info;
unsigned int uid = INSN_UID (insn);
if (old_bb == new_bb)
return;
set_block_for_insn (insn, new_bb);
if (!df)
return;
if (dump_file)
fprintf (dump_file, "changing bb of uid %d\n", uid);
insn_info = DF_INSN_UID_SAFE_GET (uid);
if (insn_info == NULL)
{
if (dump_file)
fprintf (dump_file, " unscanned insn\n");
df_insn_rescan (insn);
return;
}
if (!INSN_P (insn))
return;
df_set_bb_dirty (new_bb);
if (old_bb)
{
if (dump_file)
fprintf (dump_file, " from %d to %d\n",
old_bb->index, new_bb->index);
df_set_bb_dirty (old_bb);
}
else
if (dump_file)
fprintf (dump_file, " to %d\n", new_bb->index);
}
/* Helper function for df_ref_change_reg_with_loc. */
static void
df_ref_change_reg_with_loc_1 (struct df_reg_info *old_df,
struct df_reg_info *new_df,
unsigned int new_regno, rtx loc)
{
df_ref the_ref = old_df->reg_chain;
while (the_ref)
{
if ((!DF_REF_IS_ARTIFICIAL (the_ref))
&& DF_REF_LOC (the_ref)
&& (*DF_REF_LOC (the_ref) == loc))
{
df_ref next_ref = DF_REF_NEXT_REG (the_ref);
df_ref prev_ref = DF_REF_PREV_REG (the_ref);
df_ref *ref_ptr;
struct df_insn_info *insn_info = DF_REF_INSN_INFO (the_ref);
DF_REF_REGNO (the_ref) = new_regno;
DF_REF_REG (the_ref) = regno_reg_rtx[new_regno];
/* Pull the_ref out of the old regno chain. */
if (prev_ref)
DF_REF_NEXT_REG (prev_ref) = next_ref;
else
old_df->reg_chain = next_ref;
if (next_ref)
DF_REF_PREV_REG (next_ref) = prev_ref;
old_df->n_refs--;
/* Put the ref into the new regno chain. */
DF_REF_PREV_REG (the_ref) = NULL;
DF_REF_NEXT_REG (the_ref) = new_df->reg_chain;
if (new_df->reg_chain)
DF_REF_PREV_REG (new_df->reg_chain) = the_ref;
new_df->reg_chain = the_ref;
new_df->n_refs++;
if (DF_REF_BB (the_ref))
df_set_bb_dirty (DF_REF_BB (the_ref));
/* Need to sort the record again that the ref was in because
the regno is a sorting key. First, find the right
record. */
if (DF_REF_REG_DEF_P (the_ref))
ref_ptr = &insn_info->defs;
else if (DF_REF_FLAGS (the_ref) & DF_REF_IN_NOTE)
ref_ptr = &insn_info->eq_uses;
else
ref_ptr = &insn_info->uses;
if (dump_file)
fprintf (dump_file, "changing reg in insn %d\n",
DF_REF_INSN_UID (the_ref));
/* Stop if we find the current reference or where the reference
needs to be. */
while (*ref_ptr != the_ref && df_ref_compare (*ref_ptr, the_ref) < 0)
ref_ptr = &DF_REF_NEXT_LOC (*ref_ptr);
if (*ref_ptr != the_ref)
{
/* The reference needs to be promoted up the list. */
df_ref next = DF_REF_NEXT_LOC (the_ref);
DF_REF_NEXT_LOC (the_ref) = *ref_ptr;
*ref_ptr = the_ref;
do
ref_ptr = &DF_REF_NEXT_LOC (*ref_ptr);
while (*ref_ptr != the_ref);
*ref_ptr = next;
}
else if (DF_REF_NEXT_LOC (the_ref)
&& df_ref_compare (the_ref, DF_REF_NEXT_LOC (the_ref)) > 0)
{
/* The reference needs to be demoted down the list. */
*ref_ptr = DF_REF_NEXT_LOC (the_ref);
do
ref_ptr = &DF_REF_NEXT_LOC (*ref_ptr);
while (*ref_ptr && df_ref_compare (the_ref, *ref_ptr) > 0);
DF_REF_NEXT_LOC (the_ref) = *ref_ptr;
*ref_ptr = the_ref;
}
the_ref = next_ref;
}
else
the_ref = DF_REF_NEXT_REG (the_ref);
}
}
/* Change the regno of register LOC to NEW_REGNO and update the df
information accordingly. Refs that do not match LOC are not changed
which means that artificial refs are not changed since they have no loc.
This call is to support the SET_REGNO macro. */
void
df_ref_change_reg_with_loc (rtx loc, unsigned int new_regno)
{
unsigned int old_regno = REGNO (loc);
if (old_regno == new_regno)
return;
if (df)
{
df_grow_reg_info ();
df_ref_change_reg_with_loc_1 (DF_REG_DEF_GET (old_regno),
DF_REG_DEF_GET (new_regno),
new_regno, loc);
df_ref_change_reg_with_loc_1 (DF_REG_USE_GET (old_regno),
DF_REG_USE_GET (new_regno),
new_regno, loc);
df_ref_change_reg_with_loc_1 (DF_REG_EQ_USE_GET (old_regno),
DF_REG_EQ_USE_GET (new_regno),
new_regno, loc);
}
set_mode_and_regno (loc, GET_MODE (loc), new_regno);
}
/* Delete the mw_hardregs that point into the eq_notes. */
static void
df_mw_hardreg_chain_delete_eq_uses (struct df_insn_info *insn_info)
{
struct df_mw_hardreg **mw_ptr = &insn_info->mw_hardregs;
struct df_scan_problem_data *problem_data
= (struct df_scan_problem_data *) df_scan->problem_data;
while (*mw_ptr)
{
df_mw_hardreg *mw = *mw_ptr;
if (mw->flags & DF_REF_IN_NOTE)
{
*mw_ptr = DF_MWS_NEXT (mw);
problem_data->mw_reg_pool->remove (mw);
}
else
mw_ptr = &DF_MWS_NEXT (mw);
}
}
/* Rescan only the REG_EQUIV/REG_EQUAL notes part of INSN. */
void
df_notes_rescan (rtx_insn *insn)
{
struct df_insn_info *insn_info;
unsigned int uid = INSN_UID (insn);
if (!df)
return;
/* The client has disabled rescanning and plans to do it itself. */
if (df->changeable_flags & DF_NO_INSN_RESCAN)
return;
/* Do nothing if the insn hasn't been emitted yet. */
if (!BLOCK_FOR_INSN (insn))
return;
df_grow_bb_info (df_scan);
df_grow_reg_info ();
insn_info = DF_INSN_UID_SAFE_GET (INSN_UID (insn));
/* The client has deferred rescanning. */
if (df->changeable_flags & DF_DEFER_INSN_RESCAN)
{
if (!insn_info)
{
insn_info = df_insn_create_insn_record (insn);
insn_info->defs = 0;
insn_info->uses = 0;
insn_info->eq_uses = 0;
insn_info->mw_hardregs = 0;
}
bitmap_clear_bit (&df->insns_to_delete, uid);
/* If the insn is set to be rescanned, it does not need to also
be notes rescanned. */
if (!bitmap_bit_p (&df->insns_to_rescan, uid))
bitmap_set_bit (&df->insns_to_notes_rescan, INSN_UID (insn));
return;
}
bitmap_clear_bit (&df->insns_to_delete, uid);
bitmap_clear_bit (&df->insns_to_notes_rescan, uid);
if (insn_info)
{
basic_block bb = BLOCK_FOR_INSN (insn);
rtx note;
struct df_collection_rec collection_rec;
unsigned int i;
df_mw_hardreg_chain_delete_eq_uses (insn_info);
df_ref_chain_delete (insn_info->eq_uses);
insn_info->eq_uses = NULL;
/* Process REG_EQUIV/REG_EQUAL notes */
for (note = REG_NOTES (insn); note;
note = XEXP (note, 1))
{
switch (REG_NOTE_KIND (note))
{
case REG_EQUIV:
case REG_EQUAL:
df_uses_record (&collection_rec,
&XEXP (note, 0), DF_REF_REG_USE,
bb, insn_info, DF_REF_IN_NOTE);
default:
break;
}
}
/* Find some place to put any new mw_hardregs. */
df_canonize_collection_rec (&collection_rec);
struct df_mw_hardreg **mw_ptr = &insn_info->mw_hardregs, *mw;
FOR_EACH_VEC_ELT (collection_rec.mw_vec, i, mw)
{
while (*mw_ptr && df_mw_compare (*mw_ptr, mw) < 0)
mw_ptr = &DF_MWS_NEXT (*mw_ptr);
DF_MWS_NEXT (mw) = *mw_ptr;
*mw_ptr = mw;
mw_ptr = &DF_MWS_NEXT (mw);
}
df_refs_add_to_chains (&collection_rec, bb, insn, copy_eq_uses);
}
else
df_insn_rescan (insn);
}
/*----------------------------------------------------------------------------
Hard core instruction scanning code. No external interfaces here,
just a lot of routines that look inside insns.
----------------------------------------------------------------------------*/
/* Return true if the contents of two df_ref's are identical.
It ignores DF_REF_MARKER. */
static bool
df_ref_equal_p (df_ref ref1, df_ref ref2)
{
if (!ref2)
return false;
if (ref1 == ref2)
return true;
if (DF_REF_CLASS (ref1) != DF_REF_CLASS (ref2)
|| DF_REF_REGNO (ref1) != DF_REF_REGNO (ref2)
|| DF_REF_REG (ref1) != DF_REF_REG (ref2)
|| DF_REF_TYPE (ref1) != DF_REF_TYPE (ref2)
|| ((DF_REF_FLAGS (ref1) & ~(DF_REF_REG_MARKER + DF_REF_MW_HARDREG))
!= (DF_REF_FLAGS (ref2) & ~(DF_REF_REG_MARKER + DF_REF_MW_HARDREG)))
|| DF_REF_BB (ref1) != DF_REF_BB (ref2)
|| DF_REF_INSN_INFO (ref1) != DF_REF_INSN_INFO (ref2))
return false;
switch (DF_REF_CLASS (ref1))
{
case DF_REF_ARTIFICIAL:
case DF_REF_BASE:
return true;
case DF_REF_REGULAR:
return DF_REF_LOC (ref1) == DF_REF_LOC (ref2);
default:
gcc_unreachable ();
}
return false;
}
/* Compare REF1 and REF2 for sorting. This is only called from places
where all of the refs are of the same type, in the same insn, and
have the same bb. So these fields are not checked. */
static int
df_ref_compare (df_ref ref1, df_ref ref2)
{
if (DF_REF_CLASS (ref1) != DF_REF_CLASS (ref2))
return (int)DF_REF_CLASS (ref1) - (int)DF_REF_CLASS (ref2);
if (DF_REF_REGNO (ref1) != DF_REF_REGNO (ref2))
return (int)DF_REF_REGNO (ref1) - (int)DF_REF_REGNO (ref2);
if (DF_REF_TYPE (ref1) != DF_REF_TYPE (ref2))
return (int)DF_REF_TYPE (ref1) - (int)DF_REF_TYPE (ref2);
if (DF_REF_REG (ref1) != DF_REF_REG (ref2))
return (int)DF_REF_ORDER (ref1) - (int)DF_REF_ORDER (ref2);
/* Cannot look at the LOC field on artificial refs. */
if (DF_REF_CLASS (ref1) != DF_REF_ARTIFICIAL
&& DF_REF_LOC (ref1) != DF_REF_LOC (ref2))
return (int)DF_REF_ORDER (ref1) - (int)DF_REF_ORDER (ref2);
if (DF_REF_FLAGS (ref1) != DF_REF_FLAGS (ref2))
{
/* If two refs are identical except that one of them has is from
a mw and one is not, we need to have the one with the mw
first. */
if (DF_REF_FLAGS_IS_SET (ref1, DF_REF_MW_HARDREG) ==
DF_REF_FLAGS_IS_SET (ref2, DF_REF_MW_HARDREG))
return DF_REF_FLAGS (ref1) - DF_REF_FLAGS (ref2);
else if (DF_REF_FLAGS_IS_SET (ref1, DF_REF_MW_HARDREG))
return -1;
else
return 1;
}
return (int)DF_REF_ORDER (ref1) - (int)DF_REF_ORDER (ref2);
}
/* Like df_ref_compare, but compare two df_ref* pointers R1 and R2. */
static int
df_ref_ptr_compare (const void *r1, const void *r2)
{
return df_ref_compare (*(const df_ref *) r1, *(const df_ref *) r2);
}
/* Sort and compress a set of refs. */
static void
df_sort_and_compress_refs (vec<df_ref, va_heap> *ref_vec)
{
unsigned int count;
unsigned int i;
unsigned int dist = 0;
count = ref_vec->length ();
/* If there are 1 or 0 elements, there is nothing to do. */
if (count < 2)
return;
else if (count == 2)
{
df_ref r0 = (*ref_vec)[0];
df_ref r1 = (*ref_vec)[1];
if (df_ref_compare (r0, r1) > 0)
std::swap ((*ref_vec)[0], (*ref_vec)[1]);
}
else
{
for (i = 0; i < count - 1; i++)
{
df_ref r0 = (*ref_vec)[i];
df_ref r1 = (*ref_vec)[i + 1];
if (df_ref_compare (r0, r1) >= 0)
break;
}
/* If the array is already strictly ordered,
which is the most common case for large COUNT case
(which happens for CALL INSNs),
no need to sort and filter out duplicate.
Simply return the count.
Make sure DF_GET_ADD_REFS adds refs in the increasing order
of DF_REF_COMPARE. */
if (i == count - 1)
return;
ref_vec->qsort (df_ref_ptr_compare);
}
for (i=0; i<count-dist; i++)
{
/* Find the next ref that is not equal to the current ref. */
while (i + dist + 1 < count
&& df_ref_equal_p ((*ref_vec)[i],
(*ref_vec)[i + dist + 1]))
{
df_free_ref ((*ref_vec)[i + dist + 1]);
dist++;
}
/* Copy it down to the next position. */
if (dist && i + dist + 1 < count)
(*ref_vec)[i + 1] = (*ref_vec)[i + dist + 1];
}
count -= dist;
ref_vec->truncate (count);
}
/* Return true if the contents of two df_ref's are identical.
It ignores DF_REF_MARKER. */
static bool
df_mw_equal_p (struct df_mw_hardreg *mw1, struct df_mw_hardreg *mw2)
{
if (!mw2)
return false;
return (mw1 == mw2) ||
(mw1->mw_reg == mw2->mw_reg
&& mw1->type == mw2->type
&& mw1->flags == mw2->flags
&& mw1->start_regno == mw2->start_regno
&& mw1->end_regno == mw2->end_regno);
}
/* Compare MW1 and MW2 for sorting. */
static int
df_mw_compare (const df_mw_hardreg *mw1, const df_mw_hardreg *mw2)
{
if (mw1->type != mw2->type)
return mw1->type - mw2->type;
if (mw1->flags != mw2->flags)
return mw1->flags - mw2->flags;
if (mw1->start_regno != mw2->start_regno)
return mw1->start_regno - mw2->start_regno;
if (mw1->end_regno != mw2->end_regno)
return mw1->end_regno - mw2->end_regno;
if (mw1->mw_reg != mw2->mw_reg)
return mw1->mw_order - mw2->mw_order;
return 0;
}
/* Like df_mw_compare, but compare two df_mw_hardreg** pointers R1 and R2. */
static int
df_mw_ptr_compare (const void *m1, const void *m2)
{
return df_mw_compare (*(const df_mw_hardreg *const *) m1,
*(const df_mw_hardreg *const *) m2);
}
/* Sort and compress a set of refs. */
static void
df_sort_and_compress_mws (vec<df_mw_hardreg *, va_heap> *mw_vec)
{
unsigned int count;
struct df_scan_problem_data *problem_data
= (struct df_scan_problem_data *) df_scan->problem_data;
unsigned int i;
unsigned int dist = 0;
count = mw_vec->length ();
if (count < 2)
return;
else if (count == 2)
{
struct df_mw_hardreg *m0 = (*mw_vec)[0];
struct df_mw_hardreg *m1 = (*mw_vec)[1];
if (df_mw_compare (m0, m1) > 0)
{
struct df_mw_hardreg *tmp = (*mw_vec)[0];
(*mw_vec)[0] = (*mw_vec)[1];
(*mw_vec)[1] = tmp;
}
}
else
mw_vec->qsort (df_mw_ptr_compare);
for (i=0; i<count-dist; i++)
{
/* Find the next ref that is not equal to the current ref. */
while (i + dist + 1 < count
&& df_mw_equal_p ((*mw_vec)[i], (*mw_vec)[i + dist + 1]))
{
problem_data->mw_reg_pool->remove ((*mw_vec)[i + dist + 1]);
dist++;
}
/* Copy it down to the next position. */
if (dist && i + dist + 1 < count)
(*mw_vec)[i + 1] = (*mw_vec)[i + dist + 1];
}
count -= dist;
mw_vec->truncate (count);
}
/* Sort and remove duplicates from the COLLECTION_REC. */
static void
df_canonize_collection_rec (struct df_collection_rec *collection_rec)
{
df_sort_and_compress_refs (&collection_rec->def_vec);
df_sort_and_compress_refs (&collection_rec->use_vec);
df_sort_and_compress_refs (&collection_rec->eq_use_vec);
df_sort_and_compress_mws (&collection_rec->mw_vec);
}
/* Add the new df_ref to appropriate reg_info/ref_info chains. */
static void
df_install_ref (df_ref this_ref,
struct df_reg_info *reg_info,
struct df_ref_info *ref_info,
bool add_to_table)
{
unsigned int regno = DF_REF_REGNO (this_ref);
/* Add the ref to the reg_{def,use,eq_use} chain. */
df_ref head = reg_info->reg_chain;
reg_info->reg_chain = this_ref;
reg_info->n_refs++;
if (DF_REF_FLAGS_IS_SET (this_ref, DF_HARD_REG_LIVE))
{
gcc_assert (regno < FIRST_PSEUDO_REGISTER);
df->hard_regs_live_count[regno]++;
}
gcc_checking_assert (DF_REF_NEXT_REG (this_ref) == NULL
&& DF_REF_PREV_REG (this_ref) == NULL);
DF_REF_NEXT_REG (this_ref) = head;
/* We cannot actually link to the head of the chain. */
DF_REF_PREV_REG (this_ref) = NULL;
if (head)
DF_REF_PREV_REG (head) = this_ref;
if (add_to_table)
{
gcc_assert (ref_info->ref_order != DF_REF_ORDER_NO_TABLE);
df_check_and_grow_ref_info (ref_info, 1);
DF_REF_ID (this_ref) = ref_info->table_size;
/* Add the ref to the big array of defs. */
ref_info->refs[ref_info->table_size] = this_ref;
ref_info->table_size++;
}
else
DF_REF_ID (this_ref) = -1;
ref_info->total_size++;
}
/* This function takes one of the groups of refs (defs, uses or
eq_uses) and installs the entire group into the insn. It also adds
each of these refs into the appropriate chains. */
static df_ref
df_install_refs (basic_block bb,
const vec<df_ref, va_heap> *old_vec,
struct df_reg_info **reg_info,
struct df_ref_info *ref_info,
bool is_notes)
{
unsigned int count = old_vec->length ();
if (count)
{
bool add_to_table;
df_ref this_ref;
unsigned int ix;
switch (ref_info->ref_order)
{
case DF_REF_ORDER_UNORDERED_WITH_NOTES:
case DF_REF_ORDER_BY_REG_WITH_NOTES:
case DF_REF_ORDER_BY_INSN_WITH_NOTES:
ref_info->ref_order = DF_REF_ORDER_UNORDERED_WITH_NOTES;
add_to_table = true;
break;
case DF_REF_ORDER_UNORDERED:
case DF_REF_ORDER_BY_REG:
case DF_REF_ORDER_BY_INSN:
ref_info->ref_order = DF_REF_ORDER_UNORDERED;
add_to_table = !is_notes;
break;
default:
add_to_table = false;
break;
}
/* Do not add if ref is not in the right blocks. */
if (add_to_table && df->analyze_subset)
add_to_table = bitmap_bit_p (df->blocks_to_analyze, bb->index);
FOR_EACH_VEC_ELT (*old_vec, ix, this_ref)
{
DF_REF_NEXT_LOC (this_ref) = (ix + 1 < old_vec->length ()
? (*old_vec)[ix + 1]
: NULL);
df_install_ref (this_ref, reg_info[DF_REF_REGNO (this_ref)],
ref_info, add_to_table);
}
return (*old_vec)[0];
}
else
return 0;
}
/* This function takes the mws installs the entire group into the
insn. */
static struct df_mw_hardreg *
df_install_mws (const vec<df_mw_hardreg *, va_heap> *old_vec)
{
unsigned int count = old_vec->length ();
if (count)
{
for (unsigned int i = 0; i < count - 1; i++)
DF_MWS_NEXT ((*old_vec)[i]) = (*old_vec)[i + 1];
DF_MWS_NEXT ((*old_vec)[count - 1]) = 0;
return (*old_vec)[0];
}
else
return 0;
}
/* Add a chain of df_refs to appropriate ref chain/reg_info/ref_info
chains and update other necessary information. */
static void
df_refs_add_to_chains (struct df_collection_rec *collection_rec,
basic_block bb, rtx_insn *insn, unsigned int flags)
{
if (insn)
{
struct df_insn_info *insn_rec = DF_INSN_INFO_GET (insn);
/* If there is a vector in the collection rec, add it to the
insn. A null rec is a signal that the caller will handle the
chain specially. */
if (flags & copy_defs)
{
gcc_checking_assert (!insn_rec->defs);
insn_rec->defs
= df_install_refs (bb, &collection_rec->def_vec,
df->def_regs,
&df->def_info, false);
}
if (flags & copy_uses)
{
gcc_checking_assert (!insn_rec->uses);
insn_rec->uses
= df_install_refs (bb, &collection_rec->use_vec,
df->use_regs,
&df->use_info, false);
}
if (flags & copy_eq_uses)
{
gcc_checking_assert (!insn_rec->eq_uses);
insn_rec->eq_uses
= df_install_refs (bb, &collection_rec->eq_use_vec,
df->eq_use_regs,
&df->use_info, true);
}
if (flags & copy_mw)
{
gcc_checking_assert (!insn_rec->mw_hardregs);
insn_rec->mw_hardregs
= df_install_mws (&collection_rec->mw_vec);
}
}
else
{
struct df_scan_bb_info *bb_info = df_scan_get_bb_info (bb->index);
gcc_checking_assert (!bb_info->artificial_defs);
bb_info->artificial_defs
= df_install_refs (bb, &collection_rec->def_vec,
df->def_regs,
&df->def_info, false);
gcc_checking_assert (!bb_info->artificial_uses);
bb_info->artificial_uses
= df_install_refs (bb, &collection_rec->use_vec,
df->use_regs,
&df->use_info, false);
}
}
/* Allocate a ref and initialize its fields. */
static df_ref
df_ref_create_structure (enum df_ref_class cl,
struct df_collection_rec *collection_rec,
rtx reg, rtx *loc,
basic_block bb, struct df_insn_info *info,
enum df_ref_type ref_type,
int ref_flags)
{
df_ref this_ref = NULL;
unsigned int regno = REGNO (GET_CODE (reg) == SUBREG ? SUBREG_REG (reg) : reg);
struct df_scan_problem_data *problem_data
= (struct df_scan_problem_data *) df_scan->problem_data;
switch (cl)
{
case DF_REF_BASE:
this_ref = (df_ref) (problem_data->ref_base_pool->allocate ());
gcc_checking_assert (loc == NULL);
break;
case DF_REF_ARTIFICIAL:
this_ref = (df_ref) (problem_data->ref_artificial_pool->allocate ());
this_ref->artificial_ref.bb = bb;
gcc_checking_assert (loc == NULL);
break;
case DF_REF_REGULAR:
this_ref = (df_ref) (problem_data->ref_regular_pool->allocate ());
this_ref->regular_ref.loc = loc;
gcc_checking_assert (loc);
break;
}
DF_REF_CLASS (this_ref) = cl;
DF_REF_ID (this_ref) = -1;
DF_REF_REG (this_ref) = reg;
DF_REF_REGNO (this_ref) = regno;
DF_REF_TYPE (this_ref) = ref_type;
DF_REF_INSN_INFO (this_ref) = info;
DF_REF_CHAIN (this_ref) = NULL;
DF_REF_FLAGS (this_ref) = ref_flags;
DF_REF_NEXT_REG (this_ref) = NULL;
DF_REF_PREV_REG (this_ref) = NULL;
DF_REF_ORDER (this_ref) = df->ref_order++;
/* We need to clear this bit because fwprop, and in the future
possibly other optimizations sometimes create new refs using ond
refs as the model. */
DF_REF_FLAGS_CLEAR (this_ref, DF_HARD_REG_LIVE);
/* See if this ref needs to have DF_HARD_REG_LIVE bit set. */
if (regno < FIRST_PSEUDO_REGISTER
&& !DF_REF_IS_ARTIFICIAL (this_ref)
&& !DEBUG_INSN_P (DF_REF_INSN (this_ref)))
{
if (DF_REF_REG_DEF_P (this_ref))
{
if (!DF_REF_FLAGS_IS_SET (this_ref, DF_REF_MAY_CLOBBER))
DF_REF_FLAGS_SET (this_ref, DF_HARD_REG_LIVE);
}
else if (!(TEST_HARD_REG_BIT (elim_reg_set, regno)
&& (regno == FRAME_POINTER_REGNUM
|| regno == ARG_POINTER_REGNUM)))
DF_REF_FLAGS_SET (this_ref, DF_HARD_REG_LIVE);
}
if (collection_rec)
{
if (DF_REF_REG_DEF_P (this_ref))
collection_rec->def_vec.safe_push (this_ref);
else if (DF_REF_FLAGS (this_ref) & DF_REF_IN_NOTE)
collection_rec->eq_use_vec.safe_push (this_ref);
else
collection_rec->use_vec.safe_push (this_ref);
}
else
df_install_ref_incremental (this_ref);
return this_ref;
}
/* Create new references of type DF_REF_TYPE for each part of register REG
at address LOC within INSN of BB. */
static void
df_ref_record (enum df_ref_class cl,
struct df_collection_rec *collection_rec,
rtx reg, rtx *loc,
basic_block bb, struct df_insn_info *insn_info,
enum df_ref_type ref_type,
int ref_flags)
{
unsigned int regno;
gcc_checking_assert (REG_P (reg) || GET_CODE (reg) == SUBREG);
regno = REGNO (GET_CODE (reg) == SUBREG ? SUBREG_REG (reg) : reg);
if (regno < FIRST_PSEUDO_REGISTER)
{
struct df_mw_hardreg *hardreg = NULL;
struct df_scan_problem_data *problem_data
= (struct df_scan_problem_data *) df_scan->problem_data;
unsigned int i;
unsigned int endregno;
df_ref ref;
if (GET_CODE (reg) == SUBREG)
{
regno += subreg_regno_offset (regno, GET_MODE (SUBREG_REG (reg)),
SUBREG_BYTE (reg), GET_MODE (reg));
endregno = regno + subreg_nregs (reg);
}
else
endregno = END_REGNO (reg);
/* If this is a multiword hardreg, we create some extra
datastructures that will enable us to easily build REG_DEAD
and REG_UNUSED notes. */
if (collection_rec
&& (endregno != regno + 1) && insn_info)
{
/* Sets to a subreg of a multiword register are partial.
Sets to a non-subreg of a multiword register are not. */
if (GET_CODE (reg) == SUBREG)
ref_flags |= DF_REF_PARTIAL;
ref_flags |= DF_REF_MW_HARDREG;
hardreg = problem_data->mw_reg_pool->allocate ();
hardreg->type = ref_type;
hardreg->flags = ref_flags;
hardreg->mw_reg = reg;
hardreg->start_regno = regno;
hardreg->end_regno = endregno - 1;
hardreg->mw_order = df->ref_order++;
collection_rec->mw_vec.safe_push (hardreg);
}
for (i = regno; i < endregno; i++)
{
ref = df_ref_create_structure (cl, collection_rec, regno_reg_rtx[i], loc,
bb, insn_info, ref_type, ref_flags);
gcc_assert (ORIGINAL_REGNO (DF_REF_REG (ref)) == i);
}
}
else
{
df_ref_create_structure (cl, collection_rec, reg, loc, bb, insn_info,
ref_type, ref_flags);
}
}
/* A set to a non-paradoxical SUBREG for which the number of word_mode units
covered by the outer mode is smaller than that covered by the inner mode,
is a read-modify-write operation.
This function returns true iff the SUBREG X is such a SUBREG. */
bool
df_read_modify_subreg_p (rtx x)
{
unsigned int isize, osize;
if (GET_CODE (x) != SUBREG)
return false;
isize = GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)));
osize = GET_MODE_SIZE (GET_MODE (x));
return isize > osize
&& isize > REGMODE_NATURAL_SIZE (GET_MODE (SUBREG_REG (x)));
}
/* Process all the registers defined in the rtx pointed by LOC.
Autoincrement/decrement definitions will be picked up by df_uses_record.
Any change here has to be matched in df_find_hard_reg_defs_1. */
static void
df_def_record_1 (struct df_collection_rec *collection_rec,
rtx *loc, basic_block bb, struct df_insn_info *insn_info,
int flags)
{
rtx dst = *loc;
/* It is legal to have a set destination be a parallel. */
if (GET_CODE (dst) == PARALLEL)
{
int i;
for (i = XVECLEN (dst, 0) - 1; i >= 0; i--)
{
rtx temp = XVECEXP (dst, 0, i);
gcc_assert (GET_CODE (temp) == EXPR_LIST);
df_def_record_1 (collection_rec, &XEXP (temp, 0),
bb, insn_info, flags);
}
return;
}
if (GET_CODE (dst) == STRICT_LOW_PART)
{
flags |= DF_REF_READ_WRITE | DF_REF_PARTIAL | DF_REF_STRICT_LOW_PART;
loc = &XEXP (dst, 0);
dst = *loc;
}
if (GET_CODE (dst) == ZERO_EXTRACT)
{
flags |= DF_REF_READ_WRITE | DF_REF_PARTIAL | DF_REF_ZERO_EXTRACT;
loc = &XEXP (dst, 0);
dst = *loc;
}
/* At this point if we do not have a reg or a subreg, just return. */
if (REG_P (dst))
{
df_ref_record (DF_REF_REGULAR, collection_rec,
dst, loc, bb, insn_info, DF_REF_REG_DEF, flags);
/* We want to keep sp alive everywhere - by making all
writes to sp also use of sp. */
if (REGNO (dst) == STACK_POINTER_REGNUM)
df_ref_record (DF_REF_BASE, collection_rec,
dst, NULL, bb, insn_info, DF_REF_REG_USE, flags);
}
else if (GET_CODE (dst) == SUBREG && REG_P (SUBREG_REG (dst)))
{
if (df_read_modify_subreg_p (dst))
flags |= DF_REF_READ_WRITE | DF_REF_PARTIAL;
flags |= DF_REF_SUBREG;
df_ref_record (DF_REF_REGULAR, collection_rec,
dst, loc, bb, insn_info, DF_REF_REG_DEF, flags);
}
}
/* Process all the registers defined in the pattern rtx, X. Any change
here has to be matched in df_find_hard_reg_defs. */
static void
df_defs_record (struct df_collection_rec *collection_rec,
rtx x, basic_block bb, struct df_insn_info *insn_info,
int flags)
{
RTX_CODE code = GET_CODE (x);
int i;
switch (code)
{
case SET:
df_def_record_1 (collection_rec, &SET_DEST (x), bb, insn_info, flags);
break;
case CLOBBER:
flags |= DF_REF_MUST_CLOBBER;
df_def_record_1 (collection_rec, &XEXP (x, 0), bb, insn_info, flags);
break;
case COND_EXEC:
df_defs_record (collection_rec, COND_EXEC_CODE (x),
bb, insn_info, DF_REF_CONDITIONAL);
break;
case PARALLEL:
for (i = 0; i < XVECLEN (x, 0); i++)
df_defs_record (collection_rec, XVECEXP (x, 0, i),
bb, insn_info, flags);
break;
default:
/* No DEFs to record in other cases */
break;
}
}
/* Set bits in *DEFS for hard registers found in the rtx DST, which is the
destination of a set or clobber. This has to match the logic in
df_defs_record_1. */
static void
df_find_hard_reg_defs_1 (rtx dst, HARD_REG_SET *defs)
{
/* It is legal to have a set destination be a parallel. */
if (GET_CODE (dst) == PARALLEL)
{
int i;
for (i = XVECLEN (dst, 0) - 1; i >= 0; i--)
{
rtx temp = XVECEXP (dst, 0, i);
gcc_assert (GET_CODE (temp) == EXPR_LIST);
df_find_hard_reg_defs_1 (XEXP (temp, 0), defs);
}
return;
}
if (GET_CODE (dst) == STRICT_LOW_PART)
dst = XEXP (dst, 0);
if (GET_CODE (dst) == ZERO_EXTRACT)
dst = XEXP (dst, 0);
/* At this point if we do not have a reg or a subreg, just return. */
if (REG_P (dst) && HARD_REGISTER_P (dst))
SET_HARD_REG_BIT (*defs, REGNO (dst));
else if (GET_CODE (dst) == SUBREG
&& REG_P (SUBREG_REG (dst)) && HARD_REGISTER_P (dst))
SET_HARD_REG_BIT (*defs, REGNO (SUBREG_REG (dst)));
}
/* Set bits in *DEFS for hard registers defined in the pattern X. This
has to match the logic in df_defs_record. */
static void
df_find_hard_reg_defs (rtx x, HARD_REG_SET *defs)
{
RTX_CODE code = GET_CODE (x);
int i;
switch (code)
{
case SET:
df_find_hard_reg_defs_1 (SET_DEST (x), defs);
break;
case CLOBBER:
df_find_hard_reg_defs_1 (XEXP (x, 0), defs);
break;
case COND_EXEC:
df_find_hard_reg_defs (COND_EXEC_CODE (x), defs);
break;
case PARALLEL:
for (i = 0; i < XVECLEN (x, 0); i++)
df_find_hard_reg_defs (XVECEXP (x, 0, i), defs);
break;
default:
/* No DEFs to record in other cases */
break;
}
}
/* Process all the registers used in the rtx at address LOC. */
static void
df_uses_record (struct df_collection_rec *collection_rec,
rtx *loc, enum df_ref_type ref_type,
basic_block bb, struct df_insn_info *insn_info,
int flags)
{
RTX_CODE code;
rtx x;
retry:
x = *loc;
if (!x)
return;
code = GET_CODE (x);
switch (code)
{
case LABEL_REF:
case SYMBOL_REF:
case CONST:
CASE_CONST_ANY:
case PC:
case CC0:
case ADDR_VEC:
case ADDR_DIFF_VEC:
return;
case CLOBBER:
/* If we are clobbering a MEM, mark any registers inside the address
as being used. */
if (MEM_P (XEXP (x, 0)))
df_uses_record (collection_rec,
&XEXP (XEXP (x, 0), 0),
DF_REF_REG_MEM_STORE,
bb, insn_info,
flags);
/* If we're clobbering a REG then we have a def so ignore. */
return;
case MEM:
df_uses_record (collection_rec,
&XEXP (x, 0), DF_REF_REG_MEM_LOAD,
bb, insn_info, flags & DF_REF_IN_NOTE);
return;
case SUBREG:
/* While we're here, optimize this case. */
flags |= DF_REF_PARTIAL;
/* In case the SUBREG is not of a REG, do not optimize. */
if (!REG_P (SUBREG_REG (x)))
{
loc = &SUBREG_REG (x);
df_uses_record (collection_rec, loc, ref_type, bb, insn_info, flags);
return;
}
/* Fall through */
case REG:
df_ref_record (DF_REF_REGULAR, collection_rec,
x, loc, bb, insn_info,
ref_type, flags);
return;
case SIGN_EXTRACT:
case ZERO_EXTRACT:
{
df_uses_record (collection_rec,
&XEXP (x, 1), ref_type, bb, insn_info, flags);
df_uses_record (collection_rec,
&XEXP (x, 2), ref_type, bb, insn_info, flags);
/* If the parameters to the zero or sign extract are
constants, strip them off and recurse, otherwise there is
no information that we can gain from this operation. */
if (code == ZERO_EXTRACT)
flags |= DF_REF_ZERO_EXTRACT;
else
flags |= DF_REF_SIGN_EXTRACT;
df_uses_record (collection_rec,
&XEXP (x, 0), ref_type, bb, insn_info, flags);
return;
}
break;
case SET:
{
rtx dst = SET_DEST (x);
gcc_assert (!(flags & DF_REF_IN_NOTE));
df_uses_record (collection_rec,
&SET_SRC (x), DF_REF_REG_USE, bb, insn_info, flags);
switch (GET_CODE (dst))
{
case SUBREG:
if (df_read_modify_subreg_p (dst))
{
df_uses_record (collection_rec, &SUBREG_REG (dst),
DF_REF_REG_USE, bb, insn_info,
flags | DF_REF_READ_WRITE | DF_REF_SUBREG);
break;
}
/* Fall through. */
case REG:
case PARALLEL:
case SCRATCH:
case PC:
case CC0:
break;
case MEM:
df_uses_record (collection_rec, &XEXP (dst, 0),
DF_REF_REG_MEM_STORE, bb, insn_info, flags);
break;
case STRICT_LOW_PART:
{
rtx *temp = &XEXP (dst, 0);
/* A strict_low_part uses the whole REG and not just the
SUBREG. */
dst = XEXP (dst, 0);
df_uses_record (collection_rec,
(GET_CODE (dst) == SUBREG) ? &SUBREG_REG (dst) : temp,
DF_REF_REG_USE, bb, insn_info,
DF_REF_READ_WRITE | DF_REF_STRICT_LOW_PART);
}
break;
case ZERO_EXTRACT:
{
df_uses_record (collection_rec, &XEXP (dst, 1),
DF_REF_REG_USE, bb, insn_info, flags);
df_uses_record (collection_rec, &XEXP (dst, 2),
DF_REF_REG_USE, bb, insn_info, flags);
if (GET_CODE (XEXP (dst,0)) == MEM)
df_uses_record (collection_rec, &XEXP (dst, 0),
DF_REF_REG_USE, bb, insn_info,
flags);
else
df_uses_record (collection_rec, &XEXP (dst, 0),
DF_REF_REG_USE, bb, insn_info,
DF_REF_READ_WRITE | DF_REF_ZERO_EXTRACT);
}
break;
default:
gcc_unreachable ();
}
return;
}
case RETURN:
case SIMPLE_RETURN:
break;
case ASM_OPERANDS:
case UNSPEC_VOLATILE:
case TRAP_IF:
case ASM_INPUT:
{
/* Traditional and volatile asm instructions must be
considered to use and clobber all hard registers, all
pseudo-registers and all of memory. So must TRAP_IF and
UNSPEC_VOLATILE operations.
Consider for instance a volatile asm that changes the fpu
rounding mode. An insn should not be moved across this
even if it only uses pseudo-regs because it might give an
incorrectly rounded result.
However, flow.c's liveness computation did *not* do this,
giving the reasoning as " ?!? Unfortunately, marking all
hard registers as live causes massive problems for the
register allocator and marking all pseudos as live creates
mountains of uninitialized variable warnings."
In order to maintain the status quo with regard to liveness
and uses, we do what flow.c did and just mark any regs we
can find in ASM_OPERANDS as used. In global asm insns are
scanned and regs_asm_clobbered is filled out.
For all ASM_OPERANDS, we must traverse the vector of input
operands. We can not just fall through here since then we
would be confused by the ASM_INPUT rtx inside ASM_OPERANDS,
which do not indicate traditional asms unlike their normal
usage. */
if (code == ASM_OPERANDS)
{
int j;
for (j = 0; j < ASM_OPERANDS_INPUT_LENGTH (x); j++)
df_uses_record (collection_rec, &ASM_OPERANDS_INPUT (x, j),
DF_REF_REG_USE, bb, insn_info, flags);
return;
}
break;
}
case VAR_LOCATION:
df_uses_record (collection_rec,
&PAT_VAR_LOCATION_LOC (x),
DF_REF_REG_USE, bb, insn_info, flags);
return;
case PRE_DEC:
case POST_DEC:
case PRE_INC:
case POST_INC:
case PRE_MODIFY:
case POST_MODIFY:
gcc_assert (!DEBUG_INSN_P (insn_info->insn));
/* Catch the def of the register being modified. */
df_ref_record (DF_REF_REGULAR, collection_rec, XEXP (x, 0), &XEXP (x, 0),
bb, insn_info,
DF_REF_REG_DEF,
flags | DF_REF_READ_WRITE | DF_REF_PRE_POST_MODIFY);
/* ... Fall through to handle uses ... */
default:
break;
}
/* Recursively scan the operands of this expression. */
{
const char *fmt = GET_RTX_FORMAT (code);
int i;
for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
{
if (fmt[i] == 'e')
{
/* Tail recursive case: save a function call level. */
if (i == 0)
{
loc = &XEXP (x, 0);
goto retry;
}
df_uses_record (collection_rec, &XEXP (x, i), ref_type,
bb, insn_info, flags);
}
else if (fmt[i] == 'E')
{
int j;
for (j = 0; j < XVECLEN (x, i); j++)
df_uses_record (collection_rec,
&XVECEXP (x, i, j), ref_type,
bb, insn_info, flags);
}
}
}
return;
}
/* For all DF_REF_CONDITIONAL defs, add a corresponding uses. */
static void
df_get_conditional_uses (struct df_collection_rec *collection_rec)
{
unsigned int ix;
df_ref ref;
FOR_EACH_VEC_ELT (collection_rec->def_vec, ix, ref)
{
if (DF_REF_FLAGS_IS_SET (ref, DF_REF_CONDITIONAL))
{
df_ref use;
use = df_ref_create_structure (DF_REF_CLASS (ref), collection_rec, DF_REF_REG (ref),
DF_REF_LOC (ref), DF_REF_BB (ref),
DF_REF_INSN_INFO (ref), DF_REF_REG_USE,
DF_REF_FLAGS (ref) & ~DF_REF_CONDITIONAL);
DF_REF_REGNO (use) = DF_REF_REGNO (ref);
}
}
}
/* Get call's extra defs and uses (track caller-saved registers). */
static void
df_get_call_refs (struct df_collection_rec *collection_rec,
basic_block bb,
struct df_insn_info *insn_info,
int flags)
{
rtx note;
bool is_sibling_call;
unsigned int i;
HARD_REG_SET defs_generated;
HARD_REG_SET fn_reg_set_usage;
CLEAR_HARD_REG_SET (defs_generated);
df_find_hard_reg_defs (PATTERN (insn_info->insn), &defs_generated);
is_sibling_call = SIBLING_CALL_P (insn_info->insn);
get_call_reg_set_usage (insn_info->insn, &fn_reg_set_usage,
regs_invalidated_by_call);
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
{
if (i == STACK_POINTER_REGNUM)
/* The stack ptr is used (honorarily) by a CALL insn. */
df_ref_record (DF_REF_BASE, collection_rec, regno_reg_rtx[i],
NULL, bb, insn_info, DF_REF_REG_USE,
DF_REF_CALL_STACK_USAGE | flags);
else if (global_regs[i])
{
/* Calls to const functions cannot access any global registers and
calls to pure functions cannot set them. All other calls may
reference any of the global registers, so they are recorded as
used. */
if (!RTL_CONST_CALL_P (insn_info->insn))
{
df_ref_record (DF_REF_BASE, collection_rec, regno_reg_rtx[i],
NULL, bb, insn_info, DF_REF_REG_USE, flags);
if (!RTL_PURE_CALL_P (insn_info->insn))
df_ref_record (DF_REF_BASE, collection_rec, regno_reg_rtx[i],
NULL, bb, insn_info, DF_REF_REG_DEF, flags);
}
}
else if (TEST_HARD_REG_BIT (fn_reg_set_usage, i)
/* no clobbers for regs that are the result of the call */
&& !TEST_HARD_REG_BIT (defs_generated, i)
&& (!is_sibling_call
|| !bitmap_bit_p (df->exit_block_uses, i)
|| refers_to_regno_p (i, crtl->return_rtx)))
df_ref_record (DF_REF_BASE, collection_rec, regno_reg_rtx[i],
NULL, bb, insn_info, DF_REF_REG_DEF,
DF_REF_MAY_CLOBBER | flags);
}
/* Record the registers used to pass arguments, and explicitly
noted as clobbered. */
for (note = CALL_INSN_FUNCTION_USAGE (insn_info->insn); note;
note = XEXP (note, 1))
{