/* Move registers around to reduce number of move instructions needed.
- Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
- 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+ Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997,
+ 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
+ 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
+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
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, 51 Franklin Street, Fifth Floor, Boston, MA
-02110-1301, USA. */
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
/* This module looks for cases where matching constraints would force
#include "reload.h"
#include "timevar.h"
#include "tree-pass.h"
-
-
-/* Turn STACK_GROWS_DOWNWARD into a boolean. */
-#ifdef STACK_GROWS_DOWNWARD
-#undef STACK_GROWS_DOWNWARD
-#define STACK_GROWS_DOWNWARD 1
-#else
-#define STACK_GROWS_DOWNWARD 0
-#endif
+#include "df.h"
static int perhaps_ends_bb_p (rtx);
static int optimize_reg_copy_1 (rtx, rtx, rtx);
static void optimize_reg_copy_2 (rtx, rtx, rtx);
static void optimize_reg_copy_3 (rtx, rtx, rtx);
-static void copy_src_to_dest (rtx, rtx, rtx, int);
-static int *regmove_bb_head;
+static void copy_src_to_dest (rtx, rtx, rtx);
struct match {
int with[MAX_RECOG_OPERANDS];
static rtx discover_flags_reg (void);
static void mark_flags_life_zones (rtx);
-static void flags_set_1 (rtx, rtx, void *);
+static void flags_set_1 (rtx, const_rtx, void *);
static int try_auto_increment (rtx, rtx, rtx, rtx, HOST_WIDE_INT, int);
static int find_matches (rtx, struct match *);
&& ! CLASS_LIKELY_SPILLED_P (class1)));
}
+/* Find the place in the rtx X where REG is used as a memory address.
+ Return the MEM rtx that so uses it.
+ If PLUSCONST is nonzero, search instead for a memory address equivalent to
+ (plus REG (const_int PLUSCONST)).
+
+ If such an address does not appear, return 0.
+ If REG appears more than once, or is used other than in such an address,
+ return (rtx) 1. */
+
+static rtx
+find_use_as_address (rtx x, rtx reg, HOST_WIDE_INT plusconst)
+{
+ enum rtx_code code = GET_CODE (x);
+ const char * const fmt = GET_RTX_FORMAT (code);
+ int i;
+ rtx value = 0;
+ rtx tem;
+
+ if (code == MEM && XEXP (x, 0) == reg && plusconst == 0)
+ return x;
+
+ if (code == MEM && GET_CODE (XEXP (x, 0)) == PLUS
+ && XEXP (XEXP (x, 0), 0) == reg
+ && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT
+ && INTVAL (XEXP (XEXP (x, 0), 1)) == plusconst)
+ return x;
+
+ if (code == SIGN_EXTRACT || code == ZERO_EXTRACT)
+ {
+ /* If REG occurs inside a MEM used in a bit-field reference,
+ that is unacceptable. */
+ if (find_use_as_address (XEXP (x, 0), reg, 0) != 0)
+ return (rtx) (size_t) 1;
+ }
+
+ if (x == reg)
+ return (rtx) (size_t) 1;
+
+ for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
+ {
+ if (fmt[i] == 'e')
+ {
+ tem = find_use_as_address (XEXP (x, i), reg, plusconst);
+ if (value == 0)
+ value = tem;
+ else if (tem != 0)
+ return (rtx) (size_t) 1;
+ }
+ else if (fmt[i] == 'E')
+ {
+ int j;
+ for (j = XVECLEN (x, i) - 1; j >= 0; j--)
+ {
+ tem = find_use_as_address (XVECEXP (x, i, j), reg, plusconst);
+ if (value == 0)
+ value = tem;
+ else if (tem != 0)
+ return (rtx) (size_t) 1;
+ }
+ }
+ }
+
+ return value;
+}
+
+
/* INC_INSN is an instruction that adds INCREMENT to REG.
Try to fold INC_INSN as a post/pre in/decrement into INSN.
Iff INC_INSN_SET is nonzero, inc_insn has a destination different from src.
{
int i;
for (i = 0; i < flags_nregs; ++i)
- live |= REGNO_REG_SET_P (block->il.rtl->global_live_at_start,
- flags_regno + i);
+ live |= REGNO_REG_SET_P (df_get_live_in (block), flags_regno + i);
}
#endif
/* A subroutine of mark_flags_life_zones, called through note_stores. */
static void
-flags_set_1 (rtx x, rtx pat, void *data ATTRIBUTE_UNUSED)
+flags_set_1 (rtx x, const_rtx pat, void *data ATTRIBUTE_UNUSED)
{
if (GET_CODE (pat) == SET
&& reg_overlap_mentioned_p (x, flags_set_1_rtx))
if (INSN_P (q))
{
if (reg_mentioned_p (dest, PATTERN (q)))
- PATTERN (q) = replace_rtx (PATTERN (q), dest, src);
+ {
+ PATTERN (q) = replace_rtx (PATTERN (q), dest, src);
+ df_insn_rescan (q);
+ }
if (CALL_P (q))
{
instead moving the value to dest directly before the operation. */
static void
-copy_src_to_dest (rtx insn, rtx src, rtx dest, int old_max_uid)
+copy_src_to_dest (rtx insn, rtx src, rtx dest)
{
rtx seq;
rtx link;
rtx *p_move_notes;
int src_regno;
int dest_regno;
- int bb;
int insn_uid;
int move_uid;
*p_move_notes = NULL_RTX;
*p_insn_notes = NULL_RTX;
- /* Is the insn the head of a basic block? If so extend it. */
insn_uid = INSN_UID (insn);
move_uid = INSN_UID (move_insn);
- if (insn_uid < old_max_uid)
- {
- bb = regmove_bb_head[insn_uid];
- if (bb >= 0)
- {
- BB_HEAD (BASIC_BLOCK (bb)) = move_insn;
- regmove_bb_head[insn_uid] = -1;
- }
- }
/* Update the various register tables. */
dest_regno = REGNO (dest);
- REG_N_SETS (dest_regno) ++;
+ INC_REG_N_SETS (dest_regno, 1);
REG_LIVE_LENGTH (dest_regno)++;
- if (REGNO_FIRST_UID (dest_regno) == insn_uid)
- REGNO_FIRST_UID (dest_regno) = move_uid;
-
src_regno = REGNO (src);
if (! find_reg_note (move_insn, REG_DEAD, src))
REG_LIVE_LENGTH (src_regno)++;
-
- if (REGNO_FIRST_UID (src_regno) == insn_uid)
- REGNO_FIRST_UID (src_regno) = move_uid;
-
- if (REGNO_LAST_UID (src_regno) == insn_uid)
- REGNO_LAST_UID (src_regno) = move_uid;
}
}
may increase register pressure and make reload harder. If REG is
set in the same basic block as INSN, we don't worry about it,
because we'll probably need a register anyhow (??? but what if REG
- is used in a different basic block as well as this one?). FIRST is
- the first insn in the function. */
+ is used in a different basic block as well as this one?). */
static bool
reg_is_remote_constant_p (rtx reg, rtx insn)
reg_set_in_bb = xcalloc (max, sizeof (*reg_set_in_bb));
FOR_EACH_BB (bb)
- for (p = BB_HEAD (bb); p != NEXT_INSN (BB_END (bb));
- p = NEXT_INSN (p))
- {
- rtx s;
-
- if (!INSN_P (p))
- continue;
- s = single_set (p);
- /* This is the instruction which sets REG. If there is a
- REG_EQUAL note, then REG is equivalent to a constant. */
- if (s != 0
- && REG_P (SET_DEST (s))
- && REG_N_SETS (REGNO (SET_DEST (s))) == 1
- && find_reg_note (p, REG_EQUAL, NULL_RTX))
- reg_set_in_bb[REGNO (SET_DEST (s))] = bb;
- }
+ FOR_BB_INSNS (bb, p)
+ {
+ rtx s;
+
+ if (!INSN_P (p))
+ continue;
+ s = single_set (p);
+ /* This is the instruction which sets REG. If there is a
+ REG_EQUAL note, then REG is equivalent to a constant. */
+ if (s != 0
+ && REG_P (SET_DEST (s))
+ && REG_N_SETS (REGNO (SET_DEST (s))) == 1
+ && find_reg_note (p, REG_EQUAL, NULL_RTX))
+ reg_set_in_bb[REGNO (SET_DEST (s))] = bb;
+ }
}
+
gcc_assert (REGNO (reg) < max_reg_computed);
if (reg_set_in_bb[REGNO (reg)] == NULL)
return false;
- if (reg_set_in_bb[REGNO (reg)] != BLOCK_FOR_INSN (insn))
- return true;
- /* Look for the set. */
- for (p = BB_HEAD (BLOCK_FOR_INSN (insn)); p != insn; p = NEXT_INSN (p))
- {
- rtx s;
-
- if (!INSN_P (p))
- continue;
- s = single_set (p);
- if (s != 0
- && REG_P (SET_DEST (s)) && REGNO (SET_DEST (s)) == REGNO (reg))
- {
- /* The register is set in the same basic block. */
- return false;
- }
- }
- return true;
+ return (reg_set_in_bb[REGNO (reg)] != BLOCK_FOR_INSN (insn));
}
/* INSN is adding a CONST_INT to a REG. We search backwards looking for
static void
regmove_optimize (rtx f, int nregs)
{
- int old_max_uid = get_max_uid ();
rtx insn;
struct match match;
int pass;
int i;
rtx copy_src, copy_dst;
- basic_block bb;
/* ??? Hack. Regmove doesn't examine the CFG, and gets mightily
confused by non-call exceptions ending blocks. */
if (flag_non_call_exceptions)
return;
+ df_note_add_problem ();
+ df_analyze ();
+
+ regstat_init_n_sets_and_refs ();
+ regstat_compute_ri ();
+
/* Find out where a potential flags register is live, and so that we
can suppress some optimizations in those zones. */
mark_flags_life_zones (discover_flags_reg ());
regno_src_regno = XNEWVEC (int, nregs);
- for (i = nregs; --i >= 0; ) regno_src_regno[i] = -1;
-
- regmove_bb_head = XNEWVEC (int, old_max_uid + 1);
- for (i = old_max_uid; i >= 0; i--) regmove_bb_head[i] = -1;
- FOR_EACH_BB (bb)
- regmove_bb_head[INSN_UID (BB_HEAD (bb))] = bb->index;
+ for (i = nregs; --i >= 0; )
+ regno_src_regno[i] = -1;
/* A forward/backward pass. Replace output operands with input operands. */
dstno = REGNO (dst);
srcno = REGNO (src);
- REG_N_SETS (dstno)++;
- REG_N_SETS (srcno)--;
+ INC_REG_N_SETS (dstno, 1);
+ INC_REG_N_SETS (srcno, -1);
REG_N_CALLS_CROSSED (dstno) += num_calls;
REG_N_CALLS_CROSSED (srcno) -= num_calls;
/* If we weren't able to replace any of the alternatives, try an
alternative approach of copying the source to the destination. */
if (!success && copy_src != NULL_RTX)
- copy_src_to_dest (insn, copy_src, copy_dst, old_max_uid);
-
+ copy_src_to_dest (insn, copy_src, copy_dst);
}
}
- /* In fixup_match_1, some insns may have been inserted after basic block
- ends. Fix that here. */
- FOR_EACH_BB (bb)
- {
- rtx end = BB_END (bb);
- rtx new = end;
- rtx next = NEXT_INSN (new);
- while (next != 0 && INSN_UID (next) >= old_max_uid
- && (bb->next_bb == EXIT_BLOCK_PTR || BB_HEAD (bb->next_bb) != next))
- new = next, next = NEXT_INSN (new);
- BB_END (bb) = new;
- }
-
done:
/* Clean up. */
free (regno_src_regno);
- free (regmove_bb_head);
if (reg_set_in_bb)
{
free (reg_set_in_bb);
reg_set_in_bb = NULL;
}
+ regstat_free_n_sets_and_refs ();
+ regstat_free_ri ();
}
/* Returns nonzero if INSN's pattern has matching constraints for any operand.
&& try_auto_increment (search_end, post_inc, 0, src, newconst, 1))
post_inc = 0;
validate_change (insn, &XEXP (SET_SRC (set), 1), GEN_INT (insn_const), 0);
- REG_N_SETS (REGNO (src))++;
+ INC_REG_N_SETS (REGNO (src), 1);
REG_LIVE_LENGTH (REGNO (src))++;
}
if (overlap)
p = emit_insn_after_setloc (pat, PREV_INSN (p), INSN_LOCATOR (insn));
delete_insn (insn);
REG_NOTES (p) = notes;
+ df_notes_rescan (p);
}
}
/* Sometimes we'd generate src = const; src += n;
&& validate_change (insn, &SET_SRC (set), XEXP (note, 0), 0))
{
delete_insn (q);
- REG_N_SETS (REGNO (src))--;
+ INC_REG_N_SETS (REGNO (src), -1);
REG_N_CALLS_CROSSED (REGNO (src)) -= num_calls2;
REG_LIVE_LENGTH (REGNO (src)) -= s_length2;
insn_const = 0;
REG_N_CALLS_CROSSED (REGNO (src)) += s_num_calls;
}
- REG_N_SETS (REGNO (src))++;
- REG_N_SETS (REGNO (dst))--;
+ INC_REG_N_SETS (REGNO (src), 1);
+ INC_REG_N_SETS (REGNO (dst), -1);
REG_N_CALLS_CROSSED (REGNO (dst)) -= num_calls;
rest_of_handle_regmove (void)
{
regmove_optimize (get_insns (), max_reg_num ());
- cleanup_cfg (CLEANUP_EXPENSIVE | CLEANUP_UPDATE_LIFE);
return 0;
}
0, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
+ TODO_df_finish | TODO_verify_rtl_sharing |
TODO_dump_func |
TODO_ggc_collect, /* todo_flags_finish */
'N' /* letter */