a204196782
* basic-block.h (reg_set_iterator): New. (EXECUTE_IF_SET_IN_REG_SET): Make it iterator style. (EXECUTE_IF_AND_COMPL_IN_REG_SET): Likewise. (EXECUTE_IF_AND_IN_REG_SET): Likewise. * caller-save.c (save_call_clobbered_regs): Adjust to the new style. * cfgcleanup.c (thread_jump): Likewise. * cfgrtl.c (safe_insert_insn_on_edge): Likewise. * conflict.c (conflict_graph_compute): Likewise. * flow.c (verify_local_live_at_start, update_life_info, initialize_uninitialized_subregs, propagate_one_insn, init_propagate_block_info, free_propagate_block_info, propagate_block, dump_regset): Likewise. * global.c (global_conflicts): Likewise. * graph.c (start_bb): Likewise. * local-alloc.c (update_equiv_regs): Likewise. * loop.c (load_mems): Likewise. * reload1.c (compute_use_by_pseudos, order_regs_for_reload, find_reg, finish_spills): Likewise. * resource.c (mark_target_live_regs): Likewise. * sched-deps.c (sched_analyze_insn): Likewise. * sched-rgn.c (sched-rgn.c): Likewise. * config/frv/frv.c (frv_ifcvt_modify_tests): Likewise. From-SVN: r89226
1306 lines
39 KiB
C
1306 lines
39 KiB
C
/* Definitions for computing resource usage of specific insns.
|
||
Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004
|
||
Free Software Foundation, Inc.
|
||
|
||
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 2, 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 COPYING. If not, write to the Free
|
||
Software Foundation, 59 Temple Place - Suite 330, Boston, MA
|
||
02111-1307, USA. */
|
||
|
||
#include "config.h"
|
||
#include "system.h"
|
||
#include "coretypes.h"
|
||
#include "tm.h"
|
||
#include "toplev.h"
|
||
#include "rtl.h"
|
||
#include "tm_p.h"
|
||
#include "hard-reg-set.h"
|
||
#include "basic-block.h"
|
||
#include "function.h"
|
||
#include "regs.h"
|
||
#include "flags.h"
|
||
#include "output.h"
|
||
#include "resource.h"
|
||
#include "except.h"
|
||
#include "insn-attr.h"
|
||
#include "params.h"
|
||
|
||
/* This structure is used to record liveness information at the targets or
|
||
fallthrough insns of branches. We will most likely need the information
|
||
at targets again, so save them in a hash table rather than recomputing them
|
||
each time. */
|
||
|
||
struct target_info
|
||
{
|
||
int uid; /* INSN_UID of target. */
|
||
struct target_info *next; /* Next info for same hash bucket. */
|
||
HARD_REG_SET live_regs; /* Registers live at target. */
|
||
int block; /* Basic block number containing target. */
|
||
int bb_tick; /* Generation count of basic block info. */
|
||
};
|
||
|
||
#define TARGET_HASH_PRIME 257
|
||
|
||
/* Indicates what resources are required at the beginning of the epilogue. */
|
||
static struct resources start_of_epilogue_needs;
|
||
|
||
/* Indicates what resources are required at function end. */
|
||
static struct resources end_of_function_needs;
|
||
|
||
/* Define the hash table itself. */
|
||
static struct target_info **target_hash_table = NULL;
|
||
|
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/* For each basic block, we maintain a generation number of its basic
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||
block info, which is updated each time we move an insn from the
|
||
target of a jump. This is the generation number indexed by block
|
||
number. */
|
||
|
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static int *bb_ticks;
|
||
|
||
/* Marks registers possibly live at the current place being scanned by
|
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mark_target_live_regs. Also used by update_live_status. */
|
||
|
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static HARD_REG_SET current_live_regs;
|
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|
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/* Marks registers for which we have seen a REG_DEAD note but no assignment.
|
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Also only used by the next two functions. */
|
||
|
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static HARD_REG_SET pending_dead_regs;
|
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static void update_live_status (rtx, rtx, void *);
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static int find_basic_block (rtx, int);
|
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static rtx next_insn_no_annul (rtx);
|
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static rtx find_dead_or_set_registers (rtx, struct resources*,
|
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rtx*, int, struct resources,
|
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struct resources);
|
||
|
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/* Utility function called from mark_target_live_regs via note_stores.
|
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It deadens any CLOBBERed registers and livens any SET registers. */
|
||
|
||
static void
|
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update_live_status (rtx dest, rtx x, void *data ATTRIBUTE_UNUSED)
|
||
{
|
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int first_regno, last_regno;
|
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int i;
|
||
|
||
if (!REG_P (dest)
|
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&& (GET_CODE (dest) != SUBREG || !REG_P (SUBREG_REG (dest))))
|
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return;
|
||
|
||
if (GET_CODE (dest) == SUBREG)
|
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first_regno = subreg_regno (dest);
|
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else
|
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first_regno = REGNO (dest);
|
||
|
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last_regno = first_regno + hard_regno_nregs[first_regno][GET_MODE (dest)];
|
||
|
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if (GET_CODE (x) == CLOBBER)
|
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for (i = first_regno; i < last_regno; i++)
|
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CLEAR_HARD_REG_BIT (current_live_regs, i);
|
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else
|
||
for (i = first_regno; i < last_regno; i++)
|
||
{
|
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SET_HARD_REG_BIT (current_live_regs, i);
|
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CLEAR_HARD_REG_BIT (pending_dead_regs, i);
|
||
}
|
||
}
|
||
|
||
/* Find the number of the basic block with correct live register
|
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information that starts closest to INSN. Return -1 if we couldn't
|
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find such a basic block or the beginning is more than
|
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SEARCH_LIMIT instructions before INSN. Use SEARCH_LIMIT = -1 for
|
||
an unlimited search.
|
||
|
||
The delay slot filling code destroys the control-flow graph so,
|
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instead of finding the basic block containing INSN, we search
|
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backwards toward a BARRIER where the live register information is
|
||
correct. */
|
||
|
||
static int
|
||
find_basic_block (rtx insn, int search_limit)
|
||
{
|
||
basic_block bb;
|
||
|
||
/* Scan backwards to the previous BARRIER. Then see if we can find a
|
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label that starts a basic block. Return the basic block number. */
|
||
for (insn = prev_nonnote_insn (insn);
|
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insn && !BARRIER_P (insn) && search_limit != 0;
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insn = prev_nonnote_insn (insn), --search_limit)
|
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;
|
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|
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/* The closest BARRIER is too far away. */
|
||
if (search_limit == 0)
|
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return -1;
|
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|
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/* The start of the function. */
|
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else if (insn == 0)
|
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return ENTRY_BLOCK_PTR->next_bb->index;
|
||
|
||
/* See if any of the upcoming CODE_LABELs start a basic block. If we reach
|
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anything other than a CODE_LABEL or note, we can't find this code. */
|
||
for (insn = next_nonnote_insn (insn);
|
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insn && LABEL_P (insn);
|
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insn = next_nonnote_insn (insn))
|
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{
|
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FOR_EACH_BB (bb)
|
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if (insn == BB_HEAD (bb))
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return bb->index;
|
||
}
|
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|
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return -1;
|
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}
|
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|
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/* Similar to next_insn, but ignores insns in the delay slots of
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an annulled branch. */
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||
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||
static rtx
|
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next_insn_no_annul (rtx insn)
|
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{
|
||
if (insn)
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{
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/* If INSN is an annulled branch, skip any insns from the target
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of the branch. */
|
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if (INSN_P (insn)
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&& INSN_ANNULLED_BRANCH_P (insn)
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&& NEXT_INSN (PREV_INSN (insn)) != insn)
|
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{
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rtx next = NEXT_INSN (insn);
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enum rtx_code code = GET_CODE (next);
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|
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while ((code == INSN || code == JUMP_INSN || code == CALL_INSN)
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&& INSN_FROM_TARGET_P (next))
|
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{
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||
insn = next;
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next = NEXT_INSN (insn);
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code = GET_CODE (next);
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}
|
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}
|
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|
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insn = NEXT_INSN (insn);
|
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if (insn && NONJUMP_INSN_P (insn)
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&& GET_CODE (PATTERN (insn)) == SEQUENCE)
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insn = XVECEXP (PATTERN (insn), 0, 0);
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}
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return insn;
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}
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/* Given X, some rtl, and RES, a pointer to a `struct resource', mark
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which resources are referenced by the insn. If INCLUDE_DELAYED_EFFECTS
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is TRUE, resources used by the called routine will be included for
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CALL_INSNs. */
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void
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mark_referenced_resources (rtx x, struct resources *res,
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int include_delayed_effects)
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{
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enum rtx_code code = GET_CODE (x);
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int i, j;
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unsigned int r;
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const char *format_ptr;
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/* Handle leaf items for which we set resource flags. Also, special-case
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CALL, SET and CLOBBER operators. */
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switch (code)
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{
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case CONST:
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case CONST_INT:
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case CONST_DOUBLE:
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case CONST_VECTOR:
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case PC:
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case SYMBOL_REF:
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case LABEL_REF:
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return;
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case SUBREG:
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if (!REG_P (SUBREG_REG (x)))
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mark_referenced_resources (SUBREG_REG (x), res, 0);
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else
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{
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unsigned int regno = subreg_regno (x);
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unsigned int last_regno
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= regno + hard_regno_nregs[regno][GET_MODE (x)];
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gcc_assert (last_regno <= FIRST_PSEUDO_REGISTER);
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for (r = regno; r < last_regno; r++)
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SET_HARD_REG_BIT (res->regs, r);
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}
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return;
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case REG:
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{
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unsigned int regno = REGNO (x);
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unsigned int last_regno
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= regno + hard_regno_nregs[regno][GET_MODE (x)];
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gcc_assert (last_regno <= FIRST_PSEUDO_REGISTER);
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for (r = regno; r < last_regno; r++)
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SET_HARD_REG_BIT (res->regs, r);
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}
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return;
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case MEM:
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/* If this memory shouldn't change, it really isn't referencing
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memory. */
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if (MEM_READONLY_P (x))
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res->unch_memory = 1;
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else
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res->memory = 1;
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res->volatil |= MEM_VOLATILE_P (x);
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/* Mark registers used to access memory. */
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mark_referenced_resources (XEXP (x, 0), res, 0);
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return;
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case CC0:
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res->cc = 1;
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return;
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case UNSPEC_VOLATILE:
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case ASM_INPUT:
|
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/* Traditional asm's are always volatile. */
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res->volatil = 1;
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return;
|
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|
||
case TRAP_IF:
|
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res->volatil = 1;
|
||
break;
|
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|
||
case ASM_OPERANDS:
|
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res->volatil |= MEM_VOLATILE_P (x);
|
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|
||
/* For all ASM_OPERANDS, we must traverse the vector of input operands.
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We can not just fall through here since then we would be confused
|
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by the ASM_INPUT rtx inside ASM_OPERANDS, which do not indicate
|
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traditional asms unlike their normal usage. */
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|
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for (i = 0; i < ASM_OPERANDS_INPUT_LENGTH (x); i++)
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mark_referenced_resources (ASM_OPERANDS_INPUT (x, i), res, 0);
|
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return;
|
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|
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case CALL:
|
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/* The first operand will be a (MEM (xxx)) but doesn't really reference
|
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memory. The second operand may be referenced, though. */
|
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mark_referenced_resources (XEXP (XEXP (x, 0), 0), res, 0);
|
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mark_referenced_resources (XEXP (x, 1), res, 0);
|
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return;
|
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|
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case SET:
|
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/* Usually, the first operand of SET is set, not referenced. But
|
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registers used to access memory are referenced. SET_DEST is
|
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also referenced if it is a ZERO_EXTRACT or SIGN_EXTRACT. */
|
||
|
||
mark_referenced_resources (SET_SRC (x), res, 0);
|
||
|
||
x = SET_DEST (x);
|
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if (GET_CODE (x) == SIGN_EXTRACT
|
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|| GET_CODE (x) == ZERO_EXTRACT
|
||
|| GET_CODE (x) == STRICT_LOW_PART)
|
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mark_referenced_resources (x, res, 0);
|
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else if (GET_CODE (x) == SUBREG)
|
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x = SUBREG_REG (x);
|
||
if (MEM_P (x))
|
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mark_referenced_resources (XEXP (x, 0), res, 0);
|
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return;
|
||
|
||
case CLOBBER:
|
||
return;
|
||
|
||
case CALL_INSN:
|
||
if (include_delayed_effects)
|
||
{
|
||
/* A CALL references memory, the frame pointer if it exists, the
|
||
stack pointer, any global registers and any registers given in
|
||
USE insns immediately in front of the CALL.
|
||
|
||
However, we may have moved some of the parameter loading insns
|
||
into the delay slot of this CALL. If so, the USE's for them
|
||
don't count and should be skipped. */
|
||
rtx insn = PREV_INSN (x);
|
||
rtx sequence = 0;
|
||
int seq_size = 0;
|
||
int i;
|
||
|
||
/* If we are part of a delay slot sequence, point at the SEQUENCE. */
|
||
if (NEXT_INSN (insn) != x)
|
||
{
|
||
sequence = PATTERN (NEXT_INSN (insn));
|
||
seq_size = XVECLEN (sequence, 0);
|
||
gcc_assert (GET_CODE (sequence) == SEQUENCE);
|
||
}
|
||
|
||
res->memory = 1;
|
||
SET_HARD_REG_BIT (res->regs, STACK_POINTER_REGNUM);
|
||
if (frame_pointer_needed)
|
||
{
|
||
SET_HARD_REG_BIT (res->regs, FRAME_POINTER_REGNUM);
|
||
#if FRAME_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM
|
||
SET_HARD_REG_BIT (res->regs, HARD_FRAME_POINTER_REGNUM);
|
||
#endif
|
||
}
|
||
|
||
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
|
||
if (global_regs[i])
|
||
SET_HARD_REG_BIT (res->regs, i);
|
||
|
||
/* Check for a REG_SETJMP. If it exists, then we must
|
||
assume that this call can need any register.
|
||
|
||
This is done to be more conservative about how we handle setjmp.
|
||
We assume that they both use and set all registers. Using all
|
||
registers ensures that a register will not be considered dead
|
||
just because it crosses a setjmp call. A register should be
|
||
considered dead only if the setjmp call returns nonzero. */
|
||
if (find_reg_note (x, REG_SETJMP, NULL))
|
||
SET_HARD_REG_SET (res->regs);
|
||
|
||
{
|
||
rtx link;
|
||
|
||
for (link = CALL_INSN_FUNCTION_USAGE (x);
|
||
link;
|
||
link = XEXP (link, 1))
|
||
if (GET_CODE (XEXP (link, 0)) == USE)
|
||
{
|
||
for (i = 1; i < seq_size; i++)
|
||
{
|
||
rtx slot_pat = PATTERN (XVECEXP (sequence, 0, i));
|
||
if (GET_CODE (slot_pat) == SET
|
||
&& rtx_equal_p (SET_DEST (slot_pat),
|
||
XEXP (XEXP (link, 0), 0)))
|
||
break;
|
||
}
|
||
if (i >= seq_size)
|
||
mark_referenced_resources (XEXP (XEXP (link, 0), 0),
|
||
res, 0);
|
||
}
|
||
}
|
||
}
|
||
|
||
/* ... fall through to other INSN processing ... */
|
||
|
||
case INSN:
|
||
case JUMP_INSN:
|
||
|
||
#ifdef INSN_REFERENCES_ARE_DELAYED
|
||
if (! include_delayed_effects
|
||
&& INSN_REFERENCES_ARE_DELAYED (x))
|
||
return;
|
||
#endif
|
||
|
||
/* No special processing, just speed up. */
|
||
mark_referenced_resources (PATTERN (x), res, include_delayed_effects);
|
||
return;
|
||
|
||
default:
|
||
break;
|
||
}
|
||
|
||
/* Process each sub-expression and flag what it needs. */
|
||
format_ptr = GET_RTX_FORMAT (code);
|
||
for (i = 0; i < GET_RTX_LENGTH (code); i++)
|
||
switch (*format_ptr++)
|
||
{
|
||
case 'e':
|
||
mark_referenced_resources (XEXP (x, i), res, include_delayed_effects);
|
||
break;
|
||
|
||
case 'E':
|
||
for (j = 0; j < XVECLEN (x, i); j++)
|
||
mark_referenced_resources (XVECEXP (x, i, j), res,
|
||
include_delayed_effects);
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* A subroutine of mark_target_live_regs. Search forward from TARGET
|
||
looking for registers that are set before they are used. These are dead.
|
||
Stop after passing a few conditional jumps, and/or a small
|
||
number of unconditional branches. */
|
||
|
||
static rtx
|
||
find_dead_or_set_registers (rtx target, struct resources *res,
|
||
rtx *jump_target, int jump_count,
|
||
struct resources set, struct resources needed)
|
||
{
|
||
HARD_REG_SET scratch;
|
||
rtx insn, next;
|
||
rtx jump_insn = 0;
|
||
int i;
|
||
|
||
for (insn = target; insn; insn = next)
|
||
{
|
||
rtx this_jump_insn = insn;
|
||
|
||
next = NEXT_INSN (insn);
|
||
|
||
/* If this instruction can throw an exception, then we don't
|
||
know where we might end up next. That means that we have to
|
||
assume that whatever we have already marked as live really is
|
||
live. */
|
||
if (can_throw_internal (insn))
|
||
break;
|
||
|
||
switch (GET_CODE (insn))
|
||
{
|
||
case CODE_LABEL:
|
||
/* After a label, any pending dead registers that weren't yet
|
||
used can be made dead. */
|
||
AND_COMPL_HARD_REG_SET (pending_dead_regs, needed.regs);
|
||
AND_COMPL_HARD_REG_SET (res->regs, pending_dead_regs);
|
||
CLEAR_HARD_REG_SET (pending_dead_regs);
|
||
|
||
continue;
|
||
|
||
case BARRIER:
|
||
case NOTE:
|
||
continue;
|
||
|
||
case INSN:
|
||
if (GET_CODE (PATTERN (insn)) == USE)
|
||
{
|
||
/* If INSN is a USE made by update_block, we care about the
|
||
underlying insn. Any registers set by the underlying insn
|
||
are live since the insn is being done somewhere else. */
|
||
if (INSN_P (XEXP (PATTERN (insn), 0)))
|
||
mark_set_resources (XEXP (PATTERN (insn), 0), res, 0,
|
||
MARK_SRC_DEST_CALL);
|
||
|
||
/* All other USE insns are to be ignored. */
|
||
continue;
|
||
}
|
||
else if (GET_CODE (PATTERN (insn)) == CLOBBER)
|
||
continue;
|
||
else if (GET_CODE (PATTERN (insn)) == SEQUENCE)
|
||
{
|
||
/* An unconditional jump can be used to fill the delay slot
|
||
of a call, so search for a JUMP_INSN in any position. */
|
||
for (i = 0; i < XVECLEN (PATTERN (insn), 0); i++)
|
||
{
|
||
this_jump_insn = XVECEXP (PATTERN (insn), 0, i);
|
||
if (JUMP_P (this_jump_insn))
|
||
break;
|
||
}
|
||
}
|
||
|
||
default:
|
||
break;
|
||
}
|
||
|
||
if (JUMP_P (this_jump_insn))
|
||
{
|
||
if (jump_count++ < 10)
|
||
{
|
||
if (any_uncondjump_p (this_jump_insn)
|
||
|| GET_CODE (PATTERN (this_jump_insn)) == RETURN)
|
||
{
|
||
next = JUMP_LABEL (this_jump_insn);
|
||
if (jump_insn == 0)
|
||
{
|
||
jump_insn = insn;
|
||
if (jump_target)
|
||
*jump_target = JUMP_LABEL (this_jump_insn);
|
||
}
|
||
}
|
||
else if (any_condjump_p (this_jump_insn))
|
||
{
|
||
struct resources target_set, target_res;
|
||
struct resources fallthrough_res;
|
||
|
||
/* We can handle conditional branches here by following
|
||
both paths, and then IOR the results of the two paths
|
||
together, which will give us registers that are dead
|
||
on both paths. Since this is expensive, we give it
|
||
a much higher cost than unconditional branches. The
|
||
cost was chosen so that we will follow at most 1
|
||
conditional branch. */
|
||
|
||
jump_count += 4;
|
||
if (jump_count >= 10)
|
||
break;
|
||
|
||
mark_referenced_resources (insn, &needed, 1);
|
||
|
||
/* For an annulled branch, mark_set_resources ignores slots
|
||
filled by instructions from the target. This is correct
|
||
if the branch is not taken. Since we are following both
|
||
paths from the branch, we must also compute correct info
|
||
if the branch is taken. We do this by inverting all of
|
||
the INSN_FROM_TARGET_P bits, calling mark_set_resources,
|
||
and then inverting the INSN_FROM_TARGET_P bits again. */
|
||
|
||
if (GET_CODE (PATTERN (insn)) == SEQUENCE
|
||
&& INSN_ANNULLED_BRANCH_P (this_jump_insn))
|
||
{
|
||
for (i = 1; i < XVECLEN (PATTERN (insn), 0); i++)
|
||
INSN_FROM_TARGET_P (XVECEXP (PATTERN (insn), 0, i))
|
||
= ! INSN_FROM_TARGET_P (XVECEXP (PATTERN (insn), 0, i));
|
||
|
||
target_set = set;
|
||
mark_set_resources (insn, &target_set, 0,
|
||
MARK_SRC_DEST_CALL);
|
||
|
||
for (i = 1; i < XVECLEN (PATTERN (insn), 0); i++)
|
||
INSN_FROM_TARGET_P (XVECEXP (PATTERN (insn), 0, i))
|
||
= ! INSN_FROM_TARGET_P (XVECEXP (PATTERN (insn), 0, i));
|
||
|
||
mark_set_resources (insn, &set, 0, MARK_SRC_DEST_CALL);
|
||
}
|
||
else
|
||
{
|
||
mark_set_resources (insn, &set, 0, MARK_SRC_DEST_CALL);
|
||
target_set = set;
|
||
}
|
||
|
||
target_res = *res;
|
||
COPY_HARD_REG_SET (scratch, target_set.regs);
|
||
AND_COMPL_HARD_REG_SET (scratch, needed.regs);
|
||
AND_COMPL_HARD_REG_SET (target_res.regs, scratch);
|
||
|
||
fallthrough_res = *res;
|
||
COPY_HARD_REG_SET (scratch, set.regs);
|
||
AND_COMPL_HARD_REG_SET (scratch, needed.regs);
|
||
AND_COMPL_HARD_REG_SET (fallthrough_res.regs, scratch);
|
||
|
||
find_dead_or_set_registers (JUMP_LABEL (this_jump_insn),
|
||
&target_res, 0, jump_count,
|
||
target_set, needed);
|
||
find_dead_or_set_registers (next,
|
||
&fallthrough_res, 0, jump_count,
|
||
set, needed);
|
||
IOR_HARD_REG_SET (fallthrough_res.regs, target_res.regs);
|
||
AND_HARD_REG_SET (res->regs, fallthrough_res.regs);
|
||
break;
|
||
}
|
||
else
|
||
break;
|
||
}
|
||
else
|
||
{
|
||
/* Don't try this optimization if we expired our jump count
|
||
above, since that would mean there may be an infinite loop
|
||
in the function being compiled. */
|
||
jump_insn = 0;
|
||
break;
|
||
}
|
||
}
|
||
|
||
mark_referenced_resources (insn, &needed, 1);
|
||
mark_set_resources (insn, &set, 0, MARK_SRC_DEST_CALL);
|
||
|
||
COPY_HARD_REG_SET (scratch, set.regs);
|
||
AND_COMPL_HARD_REG_SET (scratch, needed.regs);
|
||
AND_COMPL_HARD_REG_SET (res->regs, scratch);
|
||
}
|
||
|
||
return jump_insn;
|
||
}
|
||
|
||
/* Given X, a part of an insn, and a pointer to a `struct resource',
|
||
RES, indicate which resources are modified by the insn. If
|
||
MARK_TYPE is MARK_SRC_DEST_CALL, also mark resources potentially
|
||
set by the called routine.
|
||
|
||
If IN_DEST is nonzero, it means we are inside a SET. Otherwise,
|
||
objects are being referenced instead of set.
|
||
|
||
We never mark the insn as modifying the condition code unless it explicitly
|
||
SETs CC0 even though this is not totally correct. The reason for this is
|
||
that we require a SET of CC0 to immediately precede the reference to CC0.
|
||
So if some other insn sets CC0 as a side-effect, we know it cannot affect
|
||
our computation and thus may be placed in a delay slot. */
|
||
|
||
void
|
||
mark_set_resources (rtx x, struct resources *res, int in_dest,
|
||
enum mark_resource_type mark_type)
|
||
{
|
||
enum rtx_code code;
|
||
int i, j;
|
||
unsigned int r;
|
||
const char *format_ptr;
|
||
|
||
restart:
|
||
|
||
code = GET_CODE (x);
|
||
|
||
switch (code)
|
||
{
|
||
case NOTE:
|
||
case BARRIER:
|
||
case CODE_LABEL:
|
||
case USE:
|
||
case CONST_INT:
|
||
case CONST_DOUBLE:
|
||
case CONST_VECTOR:
|
||
case LABEL_REF:
|
||
case SYMBOL_REF:
|
||
case CONST:
|
||
case PC:
|
||
/* These don't set any resources. */
|
||
return;
|
||
|
||
case CC0:
|
||
if (in_dest)
|
||
res->cc = 1;
|
||
return;
|
||
|
||
case CALL_INSN:
|
||
/* Called routine modifies the condition code, memory, any registers
|
||
that aren't saved across calls, global registers and anything
|
||
explicitly CLOBBERed immediately after the CALL_INSN. */
|
||
|
||
if (mark_type == MARK_SRC_DEST_CALL)
|
||
{
|
||
rtx link;
|
||
|
||
res->cc = res->memory = 1;
|
||
for (r = 0; r < FIRST_PSEUDO_REGISTER; r++)
|
||
if (call_used_regs[r] || global_regs[r])
|
||
SET_HARD_REG_BIT (res->regs, r);
|
||
|
||
for (link = CALL_INSN_FUNCTION_USAGE (x);
|
||
link; link = XEXP (link, 1))
|
||
if (GET_CODE (XEXP (link, 0)) == CLOBBER)
|
||
mark_set_resources (SET_DEST (XEXP (link, 0)), res, 1,
|
||
MARK_SRC_DEST);
|
||
|
||
/* Check for a REG_SETJMP. If it exists, then we must
|
||
assume that this call can clobber any register. */
|
||
if (find_reg_note (x, REG_SETJMP, NULL))
|
||
SET_HARD_REG_SET (res->regs);
|
||
}
|
||
|
||
/* ... and also what its RTL says it modifies, if anything. */
|
||
|
||
case JUMP_INSN:
|
||
case INSN:
|
||
|
||
/* An insn consisting of just a CLOBBER (or USE) is just for flow
|
||
and doesn't actually do anything, so we ignore it. */
|
||
|
||
#ifdef INSN_SETS_ARE_DELAYED
|
||
if (mark_type != MARK_SRC_DEST_CALL
|
||
&& INSN_SETS_ARE_DELAYED (x))
|
||
return;
|
||
#endif
|
||
|
||
x = PATTERN (x);
|
||
if (GET_CODE (x) != USE && GET_CODE (x) != CLOBBER)
|
||
goto restart;
|
||
return;
|
||
|
||
case SET:
|
||
/* If the source of a SET is a CALL, this is actually done by
|
||
the called routine. So only include it if we are to include the
|
||
effects of the calling routine. */
|
||
|
||
mark_set_resources (SET_DEST (x), res,
|
||
(mark_type == MARK_SRC_DEST_CALL
|
||
|| GET_CODE (SET_SRC (x)) != CALL),
|
||
mark_type);
|
||
|
||
mark_set_resources (SET_SRC (x), res, 0, MARK_SRC_DEST);
|
||
return;
|
||
|
||
case CLOBBER:
|
||
mark_set_resources (XEXP (x, 0), res, 1, MARK_SRC_DEST);
|
||
return;
|
||
|
||
case SEQUENCE:
|
||
for (i = 0; i < XVECLEN (x, 0); i++)
|
||
if (! (INSN_ANNULLED_BRANCH_P (XVECEXP (x, 0, 0))
|
||
&& INSN_FROM_TARGET_P (XVECEXP (x, 0, i))))
|
||
mark_set_resources (XVECEXP (x, 0, i), res, 0, mark_type);
|
||
return;
|
||
|
||
case POST_INC:
|
||
case PRE_INC:
|
||
case POST_DEC:
|
||
case PRE_DEC:
|
||
mark_set_resources (XEXP (x, 0), res, 1, MARK_SRC_DEST);
|
||
return;
|
||
|
||
case PRE_MODIFY:
|
||
case POST_MODIFY:
|
||
mark_set_resources (XEXP (x, 0), res, 1, MARK_SRC_DEST);
|
||
mark_set_resources (XEXP (XEXP (x, 1), 0), res, 0, MARK_SRC_DEST);
|
||
mark_set_resources (XEXP (XEXP (x, 1), 1), res, 0, MARK_SRC_DEST);
|
||
return;
|
||
|
||
case SIGN_EXTRACT:
|
||
case ZERO_EXTRACT:
|
||
mark_set_resources (XEXP (x, 0), res, in_dest, MARK_SRC_DEST);
|
||
mark_set_resources (XEXP (x, 1), res, 0, MARK_SRC_DEST);
|
||
mark_set_resources (XEXP (x, 2), res, 0, MARK_SRC_DEST);
|
||
return;
|
||
|
||
case MEM:
|
||
if (in_dest)
|
||
{
|
||
res->memory = 1;
|
||
res->unch_memory |= MEM_READONLY_P (x);
|
||
res->volatil |= MEM_VOLATILE_P (x);
|
||
}
|
||
|
||
mark_set_resources (XEXP (x, 0), res, 0, MARK_SRC_DEST);
|
||
return;
|
||
|
||
case SUBREG:
|
||
if (in_dest)
|
||
{
|
||
if (!REG_P (SUBREG_REG (x)))
|
||
mark_set_resources (SUBREG_REG (x), res, in_dest, mark_type);
|
||
else
|
||
{
|
||
unsigned int regno = subreg_regno (x);
|
||
unsigned int last_regno
|
||
= regno + hard_regno_nregs[regno][GET_MODE (x)];
|
||
|
||
gcc_assert (last_regno <= FIRST_PSEUDO_REGISTER);
|
||
for (r = regno; r < last_regno; r++)
|
||
SET_HARD_REG_BIT (res->regs, r);
|
||
}
|
||
}
|
||
return;
|
||
|
||
case REG:
|
||
if (in_dest)
|
||
{
|
||
unsigned int regno = REGNO (x);
|
||
unsigned int last_regno
|
||
= regno + hard_regno_nregs[regno][GET_MODE (x)];
|
||
|
||
gcc_assert (last_regno <= FIRST_PSEUDO_REGISTER);
|
||
for (r = regno; r < last_regno; r++)
|
||
SET_HARD_REG_BIT (res->regs, r);
|
||
}
|
||
return;
|
||
|
||
case UNSPEC_VOLATILE:
|
||
case ASM_INPUT:
|
||
/* Traditional asm's are always volatile. */
|
||
res->volatil = 1;
|
||
return;
|
||
|
||
case TRAP_IF:
|
||
res->volatil = 1;
|
||
break;
|
||
|
||
case ASM_OPERANDS:
|
||
res->volatil |= MEM_VOLATILE_P (x);
|
||
|
||
/* 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. */
|
||
|
||
for (i = 0; i < ASM_OPERANDS_INPUT_LENGTH (x); i++)
|
||
mark_set_resources (ASM_OPERANDS_INPUT (x, i), res, in_dest,
|
||
MARK_SRC_DEST);
|
||
return;
|
||
|
||
default:
|
||
break;
|
||
}
|
||
|
||
/* Process each sub-expression and flag what it needs. */
|
||
format_ptr = GET_RTX_FORMAT (code);
|
||
for (i = 0; i < GET_RTX_LENGTH (code); i++)
|
||
switch (*format_ptr++)
|
||
{
|
||
case 'e':
|
||
mark_set_resources (XEXP (x, i), res, in_dest, mark_type);
|
||
break;
|
||
|
||
case 'E':
|
||
for (j = 0; j < XVECLEN (x, i); j++)
|
||
mark_set_resources (XVECEXP (x, i, j), res, in_dest, mark_type);
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* Return TRUE if INSN is a return, possibly with a filled delay slot. */
|
||
|
||
static bool
|
||
return_insn_p (rtx insn)
|
||
{
|
||
if (GET_CODE (insn) == JUMP_INSN && GET_CODE (PATTERN (insn)) == RETURN)
|
||
return true;
|
||
|
||
if (GET_CODE (insn) == INSN && GET_CODE (PATTERN (insn)) == SEQUENCE)
|
||
return return_insn_p (XVECEXP (PATTERN (insn), 0, 0));
|
||
|
||
return false;
|
||
}
|
||
|
||
/* Set the resources that are live at TARGET.
|
||
|
||
If TARGET is zero, we refer to the end of the current function and can
|
||
return our precomputed value.
|
||
|
||
Otherwise, we try to find out what is live by consulting the basic block
|
||
information. This is tricky, because we must consider the actions of
|
||
reload and jump optimization, which occur after the basic block information
|
||
has been computed.
|
||
|
||
Accordingly, we proceed as follows::
|
||
|
||
We find the previous BARRIER and look at all immediately following labels
|
||
(with no intervening active insns) to see if any of them start a basic
|
||
block. If we hit the start of the function first, we use block 0.
|
||
|
||
Once we have found a basic block and a corresponding first insns, we can
|
||
accurately compute the live status from basic_block_live_regs and
|
||
reg_renumber. (By starting at a label following a BARRIER, we are immune
|
||
to actions taken by reload and jump.) Then we scan all insns between
|
||
that point and our target. For each CLOBBER (or for call-clobbered regs
|
||
when we pass a CALL_INSN), mark the appropriate registers are dead. For
|
||
a SET, mark them as live.
|
||
|
||
We have to be careful when using REG_DEAD notes because they are not
|
||
updated by such things as find_equiv_reg. So keep track of registers
|
||
marked as dead that haven't been assigned to, and mark them dead at the
|
||
next CODE_LABEL since reload and jump won't propagate values across labels.
|
||
|
||
If we cannot find the start of a basic block (should be a very rare
|
||
case, if it can happen at all), mark everything as potentially live.
|
||
|
||
Next, scan forward from TARGET looking for things set or clobbered
|
||
before they are used. These are not live.
|
||
|
||
Because we can be called many times on the same target, save our results
|
||
in a hash table indexed by INSN_UID. This is only done if the function
|
||
init_resource_info () was invoked before we are called. */
|
||
|
||
void
|
||
mark_target_live_regs (rtx insns, rtx target, struct resources *res)
|
||
{
|
||
int b = -1;
|
||
unsigned int i;
|
||
struct target_info *tinfo = NULL;
|
||
rtx insn;
|
||
rtx jump_insn = 0;
|
||
rtx jump_target;
|
||
HARD_REG_SET scratch;
|
||
struct resources set, needed;
|
||
|
||
/* Handle end of function. */
|
||
if (target == 0)
|
||
{
|
||
*res = end_of_function_needs;
|
||
return;
|
||
}
|
||
|
||
/* Handle return insn. */
|
||
else if (return_insn_p (target))
|
||
{
|
||
*res = end_of_function_needs;
|
||
mark_referenced_resources (target, res, 0);
|
||
return;
|
||
}
|
||
|
||
/* We have to assume memory is needed, but the CC isn't. */
|
||
res->memory = 1;
|
||
res->volatil = res->unch_memory = 0;
|
||
res->cc = 0;
|
||
|
||
/* See if we have computed this value already. */
|
||
if (target_hash_table != NULL)
|
||
{
|
||
for (tinfo = target_hash_table[INSN_UID (target) % TARGET_HASH_PRIME];
|
||
tinfo; tinfo = tinfo->next)
|
||
if (tinfo->uid == INSN_UID (target))
|
||
break;
|
||
|
||
/* Start by getting the basic block number. If we have saved
|
||
information, we can get it from there unless the insn at the
|
||
start of the basic block has been deleted. */
|
||
if (tinfo && tinfo->block != -1
|
||
&& ! INSN_DELETED_P (BB_HEAD (BASIC_BLOCK (tinfo->block))))
|
||
b = tinfo->block;
|
||
}
|
||
|
||
if (b == -1)
|
||
b = find_basic_block (target, MAX_DELAY_SLOT_LIVE_SEARCH);
|
||
|
||
if (target_hash_table != NULL)
|
||
{
|
||
if (tinfo)
|
||
{
|
||
/* If the information is up-to-date, use it. Otherwise, we will
|
||
update it below. */
|
||
if (b == tinfo->block && b != -1 && tinfo->bb_tick == bb_ticks[b])
|
||
{
|
||
COPY_HARD_REG_SET (res->regs, tinfo->live_regs);
|
||
return;
|
||
}
|
||
}
|
||
else
|
||
{
|
||
/* Allocate a place to put our results and chain it into the
|
||
hash table. */
|
||
tinfo = xmalloc (sizeof (struct target_info));
|
||
tinfo->uid = INSN_UID (target);
|
||
tinfo->block = b;
|
||
tinfo->next
|
||
= target_hash_table[INSN_UID (target) % TARGET_HASH_PRIME];
|
||
target_hash_table[INSN_UID (target) % TARGET_HASH_PRIME] = tinfo;
|
||
}
|
||
}
|
||
|
||
CLEAR_HARD_REG_SET (pending_dead_regs);
|
||
|
||
/* If we found a basic block, get the live registers from it and update
|
||
them with anything set or killed between its start and the insn before
|
||
TARGET. Otherwise, we must assume everything is live. */
|
||
if (b != -1)
|
||
{
|
||
regset regs_live = BASIC_BLOCK (b)->global_live_at_start;
|
||
unsigned int j;
|
||
unsigned int regno;
|
||
rtx start_insn, stop_insn;
|
||
reg_set_iterator rsi;
|
||
|
||
/* Compute hard regs live at start of block -- this is the real hard regs
|
||
marked live, plus live pseudo regs that have been renumbered to
|
||
hard regs. */
|
||
|
||
REG_SET_TO_HARD_REG_SET (current_live_regs, regs_live);
|
||
|
||
EXECUTE_IF_SET_IN_REG_SET (regs_live, FIRST_PSEUDO_REGISTER, i, rsi)
|
||
{
|
||
if (reg_renumber[i] >= 0)
|
||
{
|
||
regno = reg_renumber[i];
|
||
for (j = regno;
|
||
j < regno + hard_regno_nregs[regno][PSEUDO_REGNO_MODE (i)];
|
||
j++)
|
||
SET_HARD_REG_BIT (current_live_regs, j);
|
||
}
|
||
}
|
||
|
||
/* Get starting and ending insn, handling the case where each might
|
||
be a SEQUENCE. */
|
||
start_insn = (b == 0 ? insns : BB_HEAD (BASIC_BLOCK (b)));
|
||
stop_insn = target;
|
||
|
||
if (NONJUMP_INSN_P (start_insn)
|
||
&& GET_CODE (PATTERN (start_insn)) == SEQUENCE)
|
||
start_insn = XVECEXP (PATTERN (start_insn), 0, 0);
|
||
|
||
if (NONJUMP_INSN_P (stop_insn)
|
||
&& GET_CODE (PATTERN (stop_insn)) == SEQUENCE)
|
||
stop_insn = next_insn (PREV_INSN (stop_insn));
|
||
|
||
for (insn = start_insn; insn != stop_insn;
|
||
insn = next_insn_no_annul (insn))
|
||
{
|
||
rtx link;
|
||
rtx real_insn = insn;
|
||
enum rtx_code code = GET_CODE (insn);
|
||
|
||
/* If this insn is from the target of a branch, it isn't going to
|
||
be used in the sequel. If it is used in both cases, this
|
||
test will not be true. */
|
||
if ((code == INSN || code == JUMP_INSN || code == CALL_INSN)
|
||
&& INSN_FROM_TARGET_P (insn))
|
||
continue;
|
||
|
||
/* If this insn is a USE made by update_block, we care about the
|
||
underlying insn. */
|
||
if (code == INSN && GET_CODE (PATTERN (insn)) == USE
|
||
&& INSN_P (XEXP (PATTERN (insn), 0)))
|
||
real_insn = XEXP (PATTERN (insn), 0);
|
||
|
||
if (CALL_P (real_insn))
|
||
{
|
||
/* CALL clobbers all call-used regs that aren't fixed except
|
||
sp, ap, and fp. Do this before setting the result of the
|
||
call live. */
|
||
AND_COMPL_HARD_REG_SET (current_live_regs,
|
||
regs_invalidated_by_call);
|
||
|
||
/* A CALL_INSN sets any global register live, since it may
|
||
have been modified by the call. */
|
||
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
|
||
if (global_regs[i])
|
||
SET_HARD_REG_BIT (current_live_regs, i);
|
||
}
|
||
|
||
/* Mark anything killed in an insn to be deadened at the next
|
||
label. Ignore USE insns; the only REG_DEAD notes will be for
|
||
parameters. But they might be early. A CALL_INSN will usually
|
||
clobber registers used for parameters. It isn't worth bothering
|
||
with the unlikely case when it won't. */
|
||
if ((NONJUMP_INSN_P (real_insn)
|
||
&& GET_CODE (PATTERN (real_insn)) != USE
|
||
&& GET_CODE (PATTERN (real_insn)) != CLOBBER)
|
||
|| JUMP_P (real_insn)
|
||
|| CALL_P (real_insn))
|
||
{
|
||
for (link = REG_NOTES (real_insn); link; link = XEXP (link, 1))
|
||
if (REG_NOTE_KIND (link) == REG_DEAD
|
||
&& REG_P (XEXP (link, 0))
|
||
&& REGNO (XEXP (link, 0)) < FIRST_PSEUDO_REGISTER)
|
||
{
|
||
unsigned int first_regno = REGNO (XEXP (link, 0));
|
||
unsigned int last_regno
|
||
= (first_regno
|
||
+ hard_regno_nregs[first_regno]
|
||
[GET_MODE (XEXP (link, 0))]);
|
||
|
||
for (i = first_regno; i < last_regno; i++)
|
||
SET_HARD_REG_BIT (pending_dead_regs, i);
|
||
}
|
||
|
||
note_stores (PATTERN (real_insn), update_live_status, NULL);
|
||
|
||
/* If any registers were unused after this insn, kill them.
|
||
These notes will always be accurate. */
|
||
for (link = REG_NOTES (real_insn); link; link = XEXP (link, 1))
|
||
if (REG_NOTE_KIND (link) == REG_UNUSED
|
||
&& REG_P (XEXP (link, 0))
|
||
&& REGNO (XEXP (link, 0)) < FIRST_PSEUDO_REGISTER)
|
||
{
|
||
unsigned int first_regno = REGNO (XEXP (link, 0));
|
||
unsigned int last_regno
|
||
= (first_regno
|
||
+ hard_regno_nregs[first_regno]
|
||
[GET_MODE (XEXP (link, 0))]);
|
||
|
||
for (i = first_regno; i < last_regno; i++)
|
||
CLEAR_HARD_REG_BIT (current_live_regs, i);
|
||
}
|
||
}
|
||
|
||
else if (LABEL_P (real_insn))
|
||
{
|
||
/* A label clobbers the pending dead registers since neither
|
||
reload nor jump will propagate a value across a label. */
|
||
AND_COMPL_HARD_REG_SET (current_live_regs, pending_dead_regs);
|
||
CLEAR_HARD_REG_SET (pending_dead_regs);
|
||
}
|
||
|
||
/* The beginning of the epilogue corresponds to the end of the
|
||
RTL chain when there are no epilogue insns. Certain resources
|
||
are implicitly required at that point. */
|
||
else if (NOTE_P (real_insn)
|
||
&& NOTE_LINE_NUMBER (real_insn) == NOTE_INSN_EPILOGUE_BEG)
|
||
IOR_HARD_REG_SET (current_live_regs, start_of_epilogue_needs.regs);
|
||
}
|
||
|
||
COPY_HARD_REG_SET (res->regs, current_live_regs);
|
||
if (tinfo != NULL)
|
||
{
|
||
tinfo->block = b;
|
||
tinfo->bb_tick = bb_ticks[b];
|
||
}
|
||
}
|
||
else
|
||
/* We didn't find the start of a basic block. Assume everything
|
||
in use. This should happen only extremely rarely. */
|
||
SET_HARD_REG_SET (res->regs);
|
||
|
||
CLEAR_RESOURCE (&set);
|
||
CLEAR_RESOURCE (&needed);
|
||
|
||
jump_insn = find_dead_or_set_registers (target, res, &jump_target, 0,
|
||
set, needed);
|
||
|
||
/* If we hit an unconditional branch, we have another way of finding out
|
||
what is live: we can see what is live at the branch target and include
|
||
anything used but not set before the branch. We add the live
|
||
resources found using the test below to those found until now. */
|
||
|
||
if (jump_insn)
|
||
{
|
||
struct resources new_resources;
|
||
rtx stop_insn = next_active_insn (jump_insn);
|
||
|
||
mark_target_live_regs (insns, next_active_insn (jump_target),
|
||
&new_resources);
|
||
CLEAR_RESOURCE (&set);
|
||
CLEAR_RESOURCE (&needed);
|
||
|
||
/* Include JUMP_INSN in the needed registers. */
|
||
for (insn = target; insn != stop_insn; insn = next_active_insn (insn))
|
||
{
|
||
mark_referenced_resources (insn, &needed, 1);
|
||
|
||
COPY_HARD_REG_SET (scratch, needed.regs);
|
||
AND_COMPL_HARD_REG_SET (scratch, set.regs);
|
||
IOR_HARD_REG_SET (new_resources.regs, scratch);
|
||
|
||
mark_set_resources (insn, &set, 0, MARK_SRC_DEST_CALL);
|
||
}
|
||
|
||
IOR_HARD_REG_SET (res->regs, new_resources.regs);
|
||
}
|
||
|
||
if (tinfo != NULL)
|
||
{
|
||
COPY_HARD_REG_SET (tinfo->live_regs, res->regs);
|
||
}
|
||
}
|
||
|
||
/* Initialize the resources required by mark_target_live_regs ().
|
||
This should be invoked before the first call to mark_target_live_regs. */
|
||
|
||
void
|
||
init_resource_info (rtx epilogue_insn)
|
||
{
|
||
int i;
|
||
|
||
/* Indicate what resources are required to be valid at the end of the current
|
||
function. The condition code never is and memory always is. If the
|
||
frame pointer is needed, it is and so is the stack pointer unless
|
||
EXIT_IGNORE_STACK is nonzero. If the frame pointer is not needed, the
|
||
stack pointer is. Registers used to return the function value are
|
||
needed. Registers holding global variables are needed. */
|
||
|
||
end_of_function_needs.cc = 0;
|
||
end_of_function_needs.memory = 1;
|
||
end_of_function_needs.unch_memory = 0;
|
||
CLEAR_HARD_REG_SET (end_of_function_needs.regs);
|
||
|
||
if (frame_pointer_needed)
|
||
{
|
||
SET_HARD_REG_BIT (end_of_function_needs.regs, FRAME_POINTER_REGNUM);
|
||
#if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
|
||
SET_HARD_REG_BIT (end_of_function_needs.regs, HARD_FRAME_POINTER_REGNUM);
|
||
#endif
|
||
if (! EXIT_IGNORE_STACK
|
||
|| current_function_sp_is_unchanging)
|
||
SET_HARD_REG_BIT (end_of_function_needs.regs, STACK_POINTER_REGNUM);
|
||
}
|
||
else
|
||
SET_HARD_REG_BIT (end_of_function_needs.regs, STACK_POINTER_REGNUM);
|
||
|
||
if (current_function_return_rtx != 0)
|
||
mark_referenced_resources (current_function_return_rtx,
|
||
&end_of_function_needs, 1);
|
||
|
||
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
|
||
if (global_regs[i]
|
||
#ifdef EPILOGUE_USES
|
||
|| EPILOGUE_USES (i)
|
||
#endif
|
||
)
|
||
SET_HARD_REG_BIT (end_of_function_needs.regs, i);
|
||
|
||
/* The registers required to be live at the end of the function are
|
||
represented in the flow information as being dead just prior to
|
||
reaching the end of the function. For example, the return of a value
|
||
might be represented by a USE of the return register immediately
|
||
followed by an unconditional jump to the return label where the
|
||
return label is the end of the RTL chain. The end of the RTL chain
|
||
is then taken to mean that the return register is live.
|
||
|
||
This sequence is no longer maintained when epilogue instructions are
|
||
added to the RTL chain. To reconstruct the original meaning, the
|
||
start of the epilogue (NOTE_INSN_EPILOGUE_BEG) is regarded as the
|
||
point where these registers become live (start_of_epilogue_needs).
|
||
If epilogue instructions are present, the registers set by those
|
||
instructions won't have been processed by flow. Thus, those
|
||
registers are additionally required at the end of the RTL chain
|
||
(end_of_function_needs). */
|
||
|
||
start_of_epilogue_needs = end_of_function_needs;
|
||
|
||
while ((epilogue_insn = next_nonnote_insn (epilogue_insn)))
|
||
{
|
||
mark_set_resources (epilogue_insn, &end_of_function_needs, 0,
|
||
MARK_SRC_DEST_CALL);
|
||
if (return_insn_p (epilogue_insn))
|
||
break;
|
||
}
|
||
|
||
/* Allocate and initialize the tables used by mark_target_live_regs. */
|
||
target_hash_table = xcalloc (TARGET_HASH_PRIME, sizeof (struct target_info *));
|
||
bb_ticks = xcalloc (last_basic_block, sizeof (int));
|
||
}
|
||
|
||
/* Free up the resources allocated to mark_target_live_regs (). This
|
||
should be invoked after the last call to mark_target_live_regs (). */
|
||
|
||
void
|
||
free_resource_info (void)
|
||
{
|
||
if (target_hash_table != NULL)
|
||
{
|
||
int i;
|
||
|
||
for (i = 0; i < TARGET_HASH_PRIME; ++i)
|
||
{
|
||
struct target_info *ti = target_hash_table[i];
|
||
|
||
while (ti)
|
||
{
|
||
struct target_info *next = ti->next;
|
||
free (ti);
|
||
ti = next;
|
||
}
|
||
}
|
||
|
||
free (target_hash_table);
|
||
target_hash_table = NULL;
|
||
}
|
||
|
||
if (bb_ticks != NULL)
|
||
{
|
||
free (bb_ticks);
|
||
bb_ticks = NULL;
|
||
}
|
||
}
|
||
|
||
/* Clear any hashed information that we have stored for INSN. */
|
||
|
||
void
|
||
clear_hashed_info_for_insn (rtx insn)
|
||
{
|
||
struct target_info *tinfo;
|
||
|
||
if (target_hash_table != NULL)
|
||
{
|
||
for (tinfo = target_hash_table[INSN_UID (insn) % TARGET_HASH_PRIME];
|
||
tinfo; tinfo = tinfo->next)
|
||
if (tinfo->uid == INSN_UID (insn))
|
||
break;
|
||
|
||
if (tinfo)
|
||
tinfo->block = -1;
|
||
}
|
||
}
|
||
|
||
/* Increment the tick count for the basic block that contains INSN. */
|
||
|
||
void
|
||
incr_ticks_for_insn (rtx insn)
|
||
{
|
||
int b = find_basic_block (insn, MAX_DELAY_SLOT_LIVE_SEARCH);
|
||
|
||
if (b != -1)
|
||
bb_ticks[b]++;
|
||
}
|
||
|
||
/* Add TRIAL to the set of resources used at the end of the current
|
||
function. */
|
||
void
|
||
mark_end_of_function_resources (rtx trial, int include_delayed_effects)
|
||
{
|
||
mark_referenced_resources (trial, &end_of_function_needs,
|
||
include_delayed_effects);
|
||
}
|