/* Move registers around to reduce number of move instructions needed.
- Copyright (C) 1987, 88, 89, 92-97, 1998 Free Software Foundation, Inc.
+ Copyright (C) 1987, 88, 89, 92-98, 1999 Free Software Foundation, Inc.
This file is part of GNU CC.
You should have received a copy of the GNU General Public License
along with GNU CC; see the file COPYING. If not, write to
-the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+the Free Software Foundation, 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA. */
/* This module looks for cases where matching constraints would force
#include "config.h"
#include "system.h"
#include "rtl.h" /* stdio.h must precede rtl.h for FFS. */
+#include "tm_p.h"
#include "insn-config.h"
#include "recog.h"
#include "output.h"
#include "regs.h"
#include "hard-reg-set.h"
#include "flags.h"
+#include "function.h"
#include "expr.h"
#include "insn-flags.h"
#include "basic-block.h"
static void optimize_reg_copy_2 PROTO((rtx, rtx, rtx));
static void optimize_reg_copy_3 PROTO((rtx, rtx, rtx));
static rtx gen_add3_insn PROTO((rtx, rtx, rtx));
-static void copy_src_to_dest PROTO((rtx, rtx, rtx, int));
+static void copy_src_to_dest PROTO((rtx, rtx, rtx, int, int));
static int *regmove_bb_head;
struct match {
int early_clobber[MAX_RECOG_OPERANDS];
};
-#ifdef AUTO_INC_DEC
+static rtx discover_flags_reg PROTO((void));
+static void mark_flags_life_zones PROTO((rtx));
+static void flags_set_1 PROTO((rtx, rtx));
+
static int try_auto_increment PROTO((rtx, rtx, rtx, rtx, HOST_WIDE_INT, int));
-#endif
static int find_matches PROTO((rtx, struct match *));
static int fixup_match_1 PROTO((rtx, rtx, rtx, rtx, rtx, int, int, int, FILE *))
;
static int reg_is_remote_constant_p PROTO((rtx, rtx, rtx));
-static int stable_but_for_p PROTO((rtx, rtx, rtx));
+static int stable_and_no_regs_but_for_p PROTO((rtx, rtx, rtx));
static int regclass_compatible_p PROTO((int, int));
static int loop_depth;
int icode = (int) add_optab->handlers[(int) GET_MODE (r0)].insn_code;
if (icode == CODE_FOR_nothing
- || ! (*insn_operand_predicate[icode][0]) (r0, insn_operand_mode[icode][0])
- || ! (*insn_operand_predicate[icode][1]) (r1, insn_operand_mode[icode][1])
- || ! (*insn_operand_predicate[icode][2]) (c, insn_operand_mode[icode][2]))
+ || ! ((*insn_data[icode].operand[0].predicate)
+ (r0, insn_data[icode].operand[0].mode))
+ || ! ((*insn_data[icode].operand[1].predicate)
+ (r1, insn_data[icode].operand[1].mode))
+ || ! ((*insn_data[icode].operand[2].predicate)
+ (c, insn_data[icode].operand[2].mode)))
return NULL_RTX;
return (GEN_FCN (icode) (r0, r1, c));
}
-#ifdef AUTO_INC_DEC
/* INC_INSN is an instruction that adds INCREMENT to REG.
Try to fold INC_INSN as a post/pre in/decrement into INSN.
{
int size = GET_MODE_SIZE (GET_MODE (use));
if (0
-#ifdef HAVE_POST_INCREMENT
- || (pre == 0 && (inc_code = POST_INC, increment == size))
-#endif
-#ifdef HAVE_PRE_INCREMENT
- || (pre == 1 && (inc_code = PRE_INC, increment == size))
-#endif
-#ifdef HAVE_POST_DECREMENT
- || (pre == 0 && (inc_code = POST_DEC, increment == -size))
-#endif
-#ifdef HAVE_PRE_DECREMENT
- || (pre == 1 && (inc_code = PRE_DEC, increment == -size))
-#endif
+ || (HAVE_POST_INCREMENT
+ && pre == 0 && (inc_code = POST_INC, increment == size))
+ || (HAVE_PRE_INCREMENT
+ && pre == 1 && (inc_code = PRE_INC, increment == size))
+ || (HAVE_POST_DECREMENT
+ && pre == 0 && (inc_code = POST_DEC, increment == -size))
+ || (HAVE_PRE_DECREMENT
+ && pre == 1 && (inc_code = PRE_DEC, increment == -size))
)
{
if (inc_insn_set)
}
return 0;
}
-#endif /* AUTO_INC_DEC */
+\f
+/* Determine if the pattern generated by add_optab has a clobber,
+ such as might be issued for a flags hard register. To make the
+ code elsewhere simpler, we handle cc0 in this same framework.
+
+ Return the register if one was discovered. Return NULL_RTX if
+ if no flags were found. Return pc_rtx if we got confused. */
+
+static rtx
+discover_flags_reg ()
+{
+ rtx tmp;
+ tmp = gen_rtx_REG (word_mode, 10000);
+ tmp = gen_add3_insn (tmp, tmp, GEN_INT (2));
+
+ /* If we get something that isn't a simple set, or a
+ [(set ..) (clobber ..)], this whole function will go wrong. */
+ if (GET_CODE (tmp) == SET)
+ return NULL_RTX;
+ else if (GET_CODE (tmp) == PARALLEL)
+ {
+ int found;
+
+ if (XVECLEN (tmp, 0) != 2)
+ return pc_rtx;
+ tmp = XVECEXP (tmp, 0, 1);
+ if (GET_CODE (tmp) != CLOBBER)
+ return pc_rtx;
+ tmp = XEXP (tmp, 0);
+
+ /* Don't do anything foolish if the md wanted to clobber a
+ scratch or something. We only care about hard regs.
+ Moreover we don't like the notion of subregs of hard regs. */
+ if (GET_CODE (tmp) == SUBREG
+ && GET_CODE (SUBREG_REG (tmp)) == REG
+ && REGNO (SUBREG_REG (tmp)) < FIRST_PSEUDO_REGISTER)
+ return pc_rtx;
+ found = (GET_CODE (tmp) == REG && REGNO (tmp) < FIRST_PSEUDO_REGISTER);
+
+ return (found ? tmp : NULL_RTX);
+ }
+
+ return pc_rtx;
+}
+
+/* It is a tedious task identifying when the flags register is live and
+ when it is safe to optimize. Since we process the instruction stream
+ multiple times, locate and record these live zones by marking the
+ mode of the instructions --
+
+ QImode is used on the instruction at which the flags becomes live.
+
+ HImode is used within the range (exclusive) that the flags are
+ live. Thus the user of the flags is not marked.
+
+ All other instructions are cleared to VOIDmode. */
+
+/* Used to communicate with flags_set_1. */
+static rtx flags_set_1_rtx;
+static int flags_set_1_set;
+
+static void
+mark_flags_life_zones (flags)
+ rtx flags;
+{
+ int flags_regno;
+ int flags_nregs;
+ int block;
+
+#ifdef HAVE_cc0
+ /* If we found a flags register on a cc0 host, bail. */
+ if (flags == NULL_RTX)
+ flags = cc0_rtx;
+ else if (flags != cc0_rtx)
+ flags = pc_rtx;
+#endif
+
+ /* Simple cases first: if no flags, clear all modes. If confusing,
+ mark the entire function as being in a flags shadow. */
+ if (flags == NULL_RTX || flags == pc_rtx)
+ {
+ enum machine_mode mode = (flags ? HImode : VOIDmode);
+ rtx insn;
+ for (insn = get_insns(); insn; insn = NEXT_INSN (insn))
+ PUT_MODE (insn, mode);
+ return;
+ }
+
+#ifdef HAVE_cc0
+ flags_regno = -1;
+ flags_nregs = 1;
+#else
+ flags_regno = REGNO (flags);
+ flags_nregs = HARD_REGNO_NREGS (flags_regno, GET_MODE (flags));
+#endif
+ flags_set_1_rtx = flags;
+
+ /* Process each basic block. */
+ for (block = n_basic_blocks - 1; block >= 0; block--)
+ {
+ rtx insn, end;
+ int live;
+
+ insn = BLOCK_HEAD (block);
+ end = BLOCK_END (block);
+
+ /* Look out for the (unlikely) case of flags being live across
+ basic block boundaries. */
+ live = 0;
+#ifndef HAVE_cc0
+ {
+ int i;
+ for (i = 0; i < flags_nregs; ++i)
+ live |= REGNO_REG_SET_P (BASIC_BLOCK (block)->global_live_at_start,
+ flags_regno + i);
+ }
+#endif
+
+ while (1)
+ {
+ /* Process liveness in reverse order of importance --
+ alive, death, birth. This lets more important info
+ overwrite the mode of lesser info. */
+
+ if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
+ {
+#ifdef HAVE_cc0
+ /* In the cc0 case, death is not marked in reg notes,
+ but is instead the mere use of cc0 when it is alive. */
+ if (live && reg_mentioned_p (cc0_rtx, PATTERN (insn)))
+ live = 0;
+#else
+ /* In the hard reg case, we watch death notes. */
+ if (live && find_regno_note (insn, REG_DEAD, flags_regno))
+ live = 0;
+#endif
+ PUT_MODE (insn, (live ? HImode : VOIDmode));
+
+ /* In either case, birth is denoted simply by it's presence
+ as the destination of a set. */
+ flags_set_1_set = 0;
+ note_stores (PATTERN (insn), flags_set_1);
+ if (flags_set_1_set)
+ {
+ live = 1;
+ PUT_MODE (insn, QImode);
+ }
+ }
+ else
+ PUT_MODE (insn, (live ? HImode : VOIDmode));
+
+ if (insn == end)
+ break;
+ insn = NEXT_INSN (insn);
+ }
+ }
+}
+
+/* A subroutine of mark_flags_life_zones, called through note_stores. */
+static void
+flags_set_1 (x, pat)
+ rtx x, pat;
+{
+ if (GET_CODE (pat) == SET
+ && reg_overlap_mentioned_p (x, flags_set_1_rtx))
+ flags_set_1_set = 1;
+}
+\f
static int *regno_src_regno;
/* Indicate how good a choice REG (which appears as a source) is to replace
&& GET_MODE (XEXP (note, 0)) == GET_MODE (src))
{
int failed = 0;
- int length = 0;
int d_length = 0;
- int n_calls = 0;
+ int s_length = 0;
int d_n_calls = 0;
+ int s_n_calls = 0;
/* We can do the optimization. Scan forward from INSN again,
replacing regs as we go. Set FAILED if a replacement can't
insn in the REG_N_REFS updates below. If this is not
correct, no great harm is done.
-
- We do not undo this substitution if something later
- fails. Therefore, we must update the other REG_N_*
- counters now to keep them accurate. */
+ Since we do not know if we will change the lifetime of
+ SREGNO or DREGNO, we must not update REG_LIVE_LENGTH
+ or REG_N_CALLS_CROSSED at this time. */
if (sregno >= FIRST_PSEUDO_REGISTER)
- {
- REG_N_REFS (sregno) -= loop_depth;
-
- if (REG_LIVE_LENGTH (sregno) >= 0)
- {
- REG_LIVE_LENGTH (sregno) -= length;
- /* REG_LIVE_LENGTH is only an approximation after
- combine if sched is not run, so make sure that
- we still have a reasonable value. */
- if (REG_LIVE_LENGTH (sregno) < 2)
- REG_LIVE_LENGTH (sregno) = 2;
- }
-
- REG_N_CALLS_CROSSED (sregno) -= n_calls;
- }
+ REG_N_REFS (sregno) -= loop_depth;
if (dregno >= FIRST_PSEUDO_REGISTER)
- {
- REG_N_REFS (dregno) += loop_depth;
-
- if (REG_LIVE_LENGTH (dregno) >= 0)
- REG_LIVE_LENGTH (dregno) += d_length;
-
- REG_N_CALLS_CROSSED (dregno) += d_n_calls;
- }
-
- /* We've done a substitution, clear the counters. */
- length = 0;
- d_length = 0;
- n_calls = 0;
- d_n_calls = 0;
+ REG_N_REFS (dregno) += loop_depth;
}
else
{
}
}
- /* Count the insns and CALL_INSNs passed. If we passed the
- death note of DEST, show increased live length. */
- length++;
+ /* For SREGNO, count the total number of insns scanned.
+ For DREGNO, count the total number of insns scanned after
+ passing the death note for DREGNO. */
+ s_length++;
if (dest_death)
d_length++;
as a call that has been crossed. Otherwise, count it. */
if (q != p && GET_CODE (q) == CALL_INSN)
{
- n_calls++;
+ /* Similarly, total calls for SREGNO, total calls beyond
+ the death note for DREGNO. */
+ s_n_calls++;
if (dest_death)
d_n_calls++;
}
if (! failed)
{
+ /* These counters need to be updated if and only if we are
+ going to move the REG_DEAD note. */
if (sregno >= FIRST_PSEUDO_REGISTER)
{
if (REG_LIVE_LENGTH (sregno) >= 0)
{
- REG_LIVE_LENGTH (sregno) -= length;
+ REG_LIVE_LENGTH (sregno) -= s_length;
/* REG_LIVE_LENGTH is only an approximation after
combine if sched is not run, so make sure that we
still have a reasonable value. */
REG_LIVE_LENGTH (sregno) = 2;
}
- REG_N_CALLS_CROSSED (sregno) -= n_calls;
- }
-
- if (dregno >= FIRST_PSEUDO_REGISTER)
- {
- if (REG_LIVE_LENGTH (dregno) >= 0)
- REG_LIVE_LENGTH (dregno) += d_length;
-
- REG_N_CALLS_CROSSED (dregno) += d_n_calls;
+ REG_N_CALLS_CROSSED (sregno) -= s_n_calls;
}
/* Move death note of SRC from P to INSN. */
{
XEXP (dest_death, 1) = REG_NOTES (p);
REG_NOTES (p) = dest_death;
+
+ if (dregno >= FIRST_PSEUDO_REGISTER)
+ {
+ /* If and only if we are moving the death note for DREGNO,
+ then we need to update its counters. */
+ if (REG_LIVE_LENGTH (dregno) >= 0)
+ REG_LIVE_LENGTH (dregno) += d_length;
+ REG_N_CALLS_CROSSED (dregno) += d_n_calls;
+ }
}
return ! failed;
instead moving the value to dest directly before the operation. */
static void
-copy_src_to_dest (insn, src, dest, loop_depth)
+copy_src_to_dest (insn, src, dest, loop_depth, old_max_uid)
rtx insn;
rtx src;
rtx dest;
int loop_depth;
+ int old_max_uid;
{
rtx seq;
rtx link;
/* Is the insn the head of a basic block? If so extend it */
insn_uid = INSN_UID (insn);
move_uid = INSN_UID (move_insn);
- bb = regmove_bb_head[insn_uid];
- if (bb >= 0)
+ if (insn_uid < old_max_uid)
{
- basic_block_head[bb] = move_insn;
- regmove_bb_head[insn_uid] = -1;
+ bb = regmove_bb_head[insn_uid];
+ if (bb >= 0)
+ {
+ BLOCK_HEAD (bb) = move_insn;
+ regmove_bb_head[insn_uid] = -1;
+ }
}
/* Update the various register tables. */
int i;
rtx copy_src, copy_dst;
+ /* Find out where a potential flags register is live, and so that we
+ can supress some optimizations in those zones. */
+ mark_flags_life_zones (discover_flags_reg ());
+
regno_src_regno = (int *)alloca (sizeof *regno_src_regno * nregs);
for (i = nregs; --i >= 0; ) regno_src_regno[i] = -1;
regmove_bb_head = (int *)alloca (sizeof (int) * (old_max_uid + 1));
for (i = old_max_uid; i >= 0; i--) regmove_bb_head[i] = -1;
for (i = 0; i < n_basic_blocks; i++)
- regmove_bb_head[INSN_UID (basic_block_head[i])] = i;
+ regmove_bb_head[INSN_UID (BLOCK_HEAD (i))] = i;
/* A forward/backward pass. Replace output operands with input operands. */
insn = pass ? PREV_INSN (insn) : NEXT_INSN (insn))
{
rtx set;
- int insn_code_number;
- int operand_number, match_number;
+ int op_no, match_no;
if (GET_CODE (insn) == NOTE)
{
}
}
}
-#ifdef REGISTER_CONSTRAINTS
- insn_code_number
- = find_matches (insn, &match);
+ if (! flag_regmove)
+ continue;
- if (insn_code_number < 0)
+ if (! find_matches (insn, &match))
continue;
/* Now scan through the operands looking for a source operand
If it dies there, then replace the dest in both operands with
the source operand. */
- for (operand_number = 0;
- operand_number < insn_n_operands[insn_code_number];
- operand_number++)
+ for (op_no = 0; op_no < recog_data.n_operands; op_no++)
{
rtx src, dst, src_subreg;
enum reg_class src_class, dst_class;
- match_number = match.with[operand_number];
+ match_no = match.with[op_no];
/* Nothing to do if the two operands aren't supposed to match. */
- if (match_number < 0)
+ if (match_no < 0)
continue;
- src = recog_operand[operand_number];
- dst = recog_operand[match_number];
+ src = recog_data.operand[op_no];
+ dst = recog_data.operand[match_no];
if (GET_CODE (src) != REG)
continue;
if (REGNO (src) < FIRST_PSEUDO_REGISTER)
{
- if (match.commutative[operand_number] < operand_number)
+ if (match.commutative[op_no] < op_no)
regno_src_regno[REGNO (dst)] = REGNO (src);
continue;
}
if (REG_LIVE_LENGTH (REGNO (src)) < 0)
continue;
- /* operand_number/src must be a read-only operand, and
+ /* op_no/src must be a read-only operand, and
match_operand/dst must be a write-only operand. */
- if (match.use[operand_number] != READ
- || match.use[match_number] != WRITE)
+ if (match.use[op_no] != READ
+ || match.use[match_no] != WRITE)
continue;
- if (match.early_clobber[match_number]
+ if (match.early_clobber[match_no]
&& count_occurrences (PATTERN (insn), src) > 1)
continue;
/* Make sure match_operand is the destination. */
- if (recog_operand[match_number] != SET_DEST (set))
+ if (recog_data.operand[match_no] != SET_DEST (set))
continue;
- /* If the operands already match, then there is nothing to do. */
- /* But in the commutative case, we might find a better match. */
- if (operands_match_p (src, dst)
- || (match.commutative[operand_number] >= 0
- && operands_match_p (recog_operand[match.commutative
- [operand_number]], dst)
- && (replacement_quality (recog_operand[match.commutative
- [operand_number]])
- >= replacement_quality (src))))
+ /* If the operands already match, then there is nothing to do. */
+ if (operands_match_p (src, dst))
continue;
+ /* But in the commutative case, we might find a better match. */
+ if (match.commutative[op_no] >= 0)
+ {
+ rtx comm = recog_data.operand[match.commutative[op_no]];
+ if (operands_match_p (comm, dst)
+ && (replacement_quality (comm)
+ >= replacement_quality (src)))
+ continue;
+ }
+
src_class = reg_preferred_class (REGNO (src));
dst_class = reg_preferred_class (REGNO (dst));
if (! regclass_compatible_p (src_class, dst_class))
continue;
if (fixup_match_1 (insn, set, src, src_subreg, dst, pass,
- operand_number, match_number,
+ op_no, match_no,
regmove_dump_file))
break;
}
}
if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
{
- int insn_code_number = find_matches (insn, &match);
- int operand_number, match_number;
+ int op_no, match_no;
int success = 0;
-
- if (insn_code_number < 0)
+
+ if (! find_matches (insn, &match))
continue;
/* Now scan through the operands looking for a destination operand
copy_src = NULL_RTX;
copy_dst = NULL_RTX;
- for (operand_number = 0;
- operand_number < insn_n_operands[insn_code_number];
- operand_number++)
+ for (op_no = 0; op_no < recog_data.n_operands; op_no++)
{
rtx set, p, src, dst;
rtx src_note, dst_note;
enum reg_class src_class, dst_class;
int length;
- match_number = match.with[operand_number];
+ match_no = match.with[op_no];
/* Nothing to do if the two operands aren't supposed to match. */
- if (match_number < 0)
+ if (match_no < 0)
continue;
- dst = recog_operand[match_number];
- src = recog_operand[operand_number];
+ dst = recog_data.operand[match_no];
+ src = recog_data.operand[op_no];
if (GET_CODE (src) != REG)
continue;
|| REG_LIVE_LENGTH (REGNO (dst)) < 0)
continue;
- /* If the operands already match, then there is nothing to do. */
- if (operands_match_p (src, dst)
- || (match.commutative[operand_number] >= 0
- && operands_match_p (recog_operand[match.commutative[operand_number]], dst)))
+ /* If the operands already match, then there is nothing to do. */
+ if (operands_match_p (src, dst))
continue;
+ if (match.commutative[op_no] >= 0)
+ {
+ rtx comm = recog_data.operand[match.commutative[op_no]];
+ if (operands_match_p (comm, dst))
+ continue;
+ }
+
set = single_set (insn);
if (! set)
continue;
- /* match_number/dst must be a write-only operand, and
+ /* match_no/dst must be a write-only operand, and
operand_operand/src must be a read-only operand. */
- if (match.use[operand_number] != READ
- || match.use[match_number] != WRITE)
+ if (match.use[op_no] != READ
+ || match.use[match_no] != WRITE)
continue;
- if (match.early_clobber[match_number]
+ if (match.early_clobber[match_no]
&& count_occurrences (PATTERN (insn), src) > 1)
continue;
- /* Make sure match_number is the destination. */
- if (recog_operand[match_number] != SET_DEST (set))
+ /* Make sure match_no is the destination. */
+ if (recog_data.operand[match_no] != SET_DEST (set))
continue;
if (REGNO (src) < FIRST_PSEUDO_REGISTER)
if (regmove_dump_file)
fprintf (regmove_dump_file,
"Could fix operand %d of insn %d matching operand %d.\n",
- operand_number, INSN_UID (insn), match_number);
+ op_no, INSN_UID (insn), match_no);
/* Scan backward to find the first instruction that uses
the input operand. If the operand is set here, then
- replace it in both instructions with match_number. */
+ replace it in both instructions with match_no. */
for (length = 0, p = PREV_INSN (insn); p; p = PREV_INSN (p))
{
validate_replace_rtx (dst, src, insn);
/* Now make sure the dst is right. */
validate_change (insn,
- recog_operand_loc[match_number],
+ recog_data.operand_loc[match_no],
dst, 0);
}
}
if (regmove_dump_file)
fprintf (regmove_dump_file,
"Fixed operand %d of insn %d matching operand %d.\n",
- operand_number, INSN_UID (insn), match_number);
+ op_no, INSN_UID (insn), match_no);
break;
}
/* If we weren't able to replace any of the alternatives, try an
alternative appoach of copying the source to the destination. */
if (!success && copy_src != NULL_RTX)
- copy_src_to_dest (insn, copy_src, copy_dst, loop_depth);
+ copy_src_to_dest (insn, copy_src, copy_dst, loop_depth,
+ old_max_uid);
}
}
-#endif /* REGISTER_CONSTRAINTS */
/* In fixup_match_1, some insns may have been inserted after basic block
ends. Fix that here. */
for (i = 0; i < n_basic_blocks; i++)
{
- rtx end = basic_block_end[i];
+ rtx end = BLOCK_END (i);
rtx new = end;
rtx next = NEXT_INSN (new);
while (next != 0 && INSN_UID (next) >= old_max_uid
- && (i == n_basic_blocks - 1 || basic_block_head[i + 1] != next))
+ && (i == n_basic_blocks - 1 || BLOCK_HEAD (i + 1) != next))
new = next, next = NEXT_INSN (new);
- basic_block_end[i] = new;
+ BLOCK_END (i) = new;
}
}
-/* Returns the INSN_CODE for INSN if its pattern has matching constraints for
- any operand. Returns -1 if INSN can't be recognized, or if the alternative
- can't be determined.
+/* Returns nonzero if INSN's pattern has matching constraints for any operand.
+ Returns 0 if INSN can't be recognized, or if the alternative can't be
+ determined.
Initialize the info in MATCHP based on the constraints. */
struct match *matchp;
{
int likely_spilled[MAX_RECOG_OPERANDS];
- int operand_number;
- int insn_code_number = recog_memoized (insn);
+ int op_no;
int any_matches = 0;
- if (insn_code_number < 0)
- return -1;
-
- insn_extract (insn);
- if (! constrain_operands (insn_code_number, 0))
- return -1;
+ extract_insn (insn);
+ if (! constrain_operands (0))
+ return 0;
/* Must initialize this before main loop, because the code for
the commutative case may set matches for operands other than
the current one. */
- for (operand_number = insn_n_operands[insn_code_number];
- --operand_number >= 0; )
- matchp->with[operand_number] = matchp->commutative[operand_number] = -1;
+ for (op_no = recog_data.n_operands; --op_no >= 0; )
+ matchp->with[op_no] = matchp->commutative[op_no] = -1;
- for (operand_number = 0; operand_number < insn_n_operands[insn_code_number];
- operand_number++)
+ for (op_no = 0; op_no < recog_data.n_operands; op_no++)
{
- char *p, c;
+ const char *p;
+ char c;
int i = 0;
- p = insn_operand_constraint[insn_code_number][operand_number];
+ p = recog_data.constraints[op_no];
- likely_spilled[operand_number] = 0;
- matchp->use[operand_number] = READ;
- matchp->early_clobber[operand_number] = 0;
+ likely_spilled[op_no] = 0;
+ matchp->use[op_no] = READ;
+ matchp->early_clobber[op_no] = 0;
if (*p == '=')
- matchp->use[operand_number] = WRITE;
+ matchp->use[op_no] = WRITE;
else if (*p == '+')
- matchp->use[operand_number] = READWRITE;
+ matchp->use[op_no] = READWRITE;
for (;*p && i < which_alternative; p++)
if (*p == ',')
case '+':
break;
case '&':
- matchp->early_clobber[operand_number] = 1;
+ matchp->early_clobber[op_no] = 1;
break;
case '%':
- matchp->commutative[operand_number] = operand_number + 1;
- matchp->commutative[operand_number + 1] = operand_number;
+ matchp->commutative[op_no] = op_no + 1;
+ matchp->commutative[op_no + 1] = op_no;
break;
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
c -= '0';
- if (c < operand_number && likely_spilled[(unsigned char) c])
+ if (c < op_no && likely_spilled[(unsigned char) c])
break;
- matchp->with[operand_number] = c;
+ matchp->with[op_no] = c;
any_matches = 1;
- if (matchp->commutative[operand_number] >= 0)
- matchp->with[matchp->commutative[operand_number]] = c;
+ if (matchp->commutative[op_no] >= 0)
+ matchp->with[matchp->commutative[op_no]] = c;
break;
case 'a': case 'b': case 'c': case 'd': case 'e': case 'f': case 'h':
case 'j': case 'k': case 'l': case 'p': case 'q': case 't': case 'u':
case 'v': case 'w': case 'x': case 'y': case 'z': case 'A': case 'B':
case 'C': case 'D': case 'W': case 'Y': case 'Z':
- if (CLASS_LIKELY_SPILLED_P (REG_CLASS_FROM_LETTER (c)))
- likely_spilled[operand_number] = 1;
+ if (CLASS_LIKELY_SPILLED_P (REG_CLASS_FROM_LETTER ((unsigned char)c)))
+ likely_spilled[op_no] = 1;
break;
}
}
- return any_matches ? insn_code_number : -1;
+ return any_matches;
}
/* Try to replace output operand DST in SET, with input operand SRC. SET is
- the only set in INSN. INSN has just been recgnized and constrained.
+ the only set in INSN. INSN has just been recognized and constrained.
SRC is operand number OPERAND_NUMBER in INSN.
DST is operand number MATCH_NUMBER in INSN.
If BACKWARD is nonzero, we have been called in a backward pass.
rtx src_note = find_reg_note (insn, REG_DEAD, src), dst_note;
int length, s_length, true_loop_depth;
+ /* If SRC is marked as unchanging, we may not change it.
+ ??? Maybe we could get better code by removing the unchanging bit
+ instead, and changing it back if we don't succeed? */
+ if (RTX_UNCHANGING_P (src))
+ return 0;
+
if (! src_note)
{
/* Look for (set (regX) (op regA constX))
&& XEXP (SET_SRC (set), 0) == src
&& GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
insn_const = INTVAL (XEXP (SET_SRC (set), 1));
- else if (! stable_but_for_p (SET_SRC (set), src, dst))
+ else if (! stable_and_no_regs_but_for_p (SET_SRC (set), src, dst))
return 0;
else
/* We might find a src_note while scanning. */
if ((dst_note = find_regno_note (p, REG_DEAD, REGNO (dst)))
&& (GET_MODE (XEXP (dst_note, 0)) == GET_MODE (dst)))
{
+ /* If we would be moving INSN, check that we won't move it
+ into the shadow of a live a live flags register. */
+ /* ??? We only try to move it in front of P, although
+ we could move it anywhere between OVERLAP and P. */
+ if (overlap && GET_MODE (PREV_INSN (p)) != VOIDmode)
+ break;
+
if (! src_note)
{
rtx q;
&& GET_CODE (SET_DEST (single_set (p))) == REG
&& (REGNO (SET_DEST (single_set (p)))
< FIRST_PSEUDO_REGISTER))
-#ifdef HAVE_cc0
- /* We may not emit an insn directly
- after P if the latter sets CC0. */
- && ! sets_cc0_p (PATTERN (p))
-#endif
- )
-
+ /* We may only emit an insn directly after P if we
+ are not in the shadow of a live flags register. */
+ && GET_MODE (p) == VOIDmode)
{
search_end = q;
q = insn;
validate_change (q, &XEXP (SET_SRC (set2), 1),
GEN_INT (newconst), 1);
}
- validate_change (insn, recog_operand_loc[match_number], src, 1);
+ validate_change (insn, recog_data.operand_loc[match_number], src, 1);
if (validate_replace_rtx (dst, src_subreg, p))
success = 1;
break;
break;
if (! src_note && reg_overlap_mentioned_p (src, PATTERN (p)))
{
- /* INSN was already checked to be movable when
- we found no REG_DEAD note for src on it. */
+ /* INSN was already checked to be movable wrt. the registers that it
+ sets / uses when we found no REG_DEAD note for src on it, but it
+ still might clobber the flags register. We'll have to check that
+ we won't insert it into the shadow of a live flags register when
+ we finally know where we are to move it. */
overlap = p;
src_note = find_reg_note (p, REG_DEAD, src);
}
if (code == MINUS)
{
post_inc = emit_insn_after (copy_rtx (PATTERN (insn)), p);
-#if defined (HAVE_PRE_INCREMENT) || defined (HAVE_PRE_DECREMENT)
- if (search_end
+ if ((HAVE_PRE_INCREMENT || HAVE_PRE_DECREMENT)
+ && search_end
&& try_auto_increment (search_end, post_inc, 0, src, newconst, 1))
post_inc = 0;
-#endif
validate_change (insn, &XEXP (SET_SRC (set), 1), GEN_INT (insn_const), 0);
REG_N_SETS (REGNO (src))++;
REG_N_REFS (REGNO (src)) += true_loop_depth;
rtx pat = PATTERN (insn);
if (src_note)
remove_note (overlap, src_note);
-#if defined (HAVE_POST_INCREMENT) || defined (HAVE_POST_DECREMENT)
- if (code == PLUS
+ if ((HAVE_POST_INCREMENT || HAVE_POST_DECREMENT)
+ && code == PLUS
&& try_auto_increment (overlap, insn, 0, src, insn_const, 0))
insn = overlap;
else
-#endif
{
rtx notes = REG_NOTES (insn);
NOTE_SOURCE_FILE (insn) = 0;
/* emit_insn_after_with_line_notes has no
return value, so search for the new insn. */
- for (insn = p; PATTERN (insn) != pat; )
+ insn = p;
+ while (GET_RTX_CLASS (GET_CODE (insn)) != 'i'
+ || PATTERN (insn) != pat)
insn = PREV_INSN (insn);
REG_NOTES (insn) = notes;
}
}
- /* Don't remove this seemingly useless if, it is needed to pair with the
- else in the next two conditionally included code blocks. */
- if (0)
- {;}
-#if defined (HAVE_PRE_INCREMENT) || defined (HAVE_PRE_DECREMENT)
- else if ((code == PLUS || code == MINUS) && insn_const
+ if ((HAVE_PRE_INCREMENT || HAVE_PRE_DECREMENT)
+ && (code == PLUS || code == MINUS) && insn_const
&& try_auto_increment (p, insn, 0, src, insn_const, 1))
insn = p;
-#endif
-#if defined (HAVE_POST_INCREMENT) || defined (HAVE_POST_DECREMENT)
- else if (post_inc
+ else if ((HAVE_POST_INCREMENT || HAVE_POST_DECREMENT)
+ && post_inc
&& try_auto_increment (p, post_inc, post_inc_set, src, newconst, 0))
post_inc = 0;
-#endif
-#if defined (HAVE_PRE_INCREMENT) || defined (HAVE_PRE_DECREMENT)
/* If post_inc still prevails, try to find an
insn where it can be used as a pre-in/decrement.
If code is MINUS, this was already tried. */
if (post_inc && code == PLUS
/* Check that newconst is likely to be usable
in a pre-in/decrement before starting the search. */
- && (0
-#if defined (HAVE_PRE_INCREMENT)
- || (newconst > 0 && newconst <= MOVE_MAX)
-#endif
-#if defined (HAVE_PRE_DECREMENT)
- || (newconst < 0 && newconst >= -MOVE_MAX)
-#endif
- ) && exact_log2 (newconst))
+ && ((HAVE_PRE_INCREMENT && newconst > 0 && newconst <= MOVE_MAX)
+ || (HAVE_PRE_DECREMENT && newconst < 0 && newconst >= -MOVE_MAX))
+ && exact_log2 (newconst))
{
rtx q, inc_dest;
}
}
}
-#endif /* defined (HAVE_PRE_INCREMENT) || defined (HAVE_PRE_DECREMENT) */
/* Move the death note for DST to INSN if it is used
there. */
if (reg_overlap_mentioned_p (dst, PATTERN (insn)))
}
-/* return nonzero if X is stable but for mentioning SRC or mentioning /
- changing DST . If in doubt, presume it is unstable. */
+/* return nonzero if X is stable and mentions no regsiters but for
+ mentioning SRC or mentioning / changing DST . If in doubt, presume
+ it is unstable.
+ The rationale is that we want to check if we can move an insn easily
+ while just paying attention to SRC and DST. A register is considered
+ stable if it has the RTX_UNCHANGING_P bit set, but that would still
+ leave the burden to update REG_DEAD / REG_UNUSED notes, so we don't
+ want any registers but SRC and DST. */
static int
-stable_but_for_p (x, src, dst)
+stable_and_no_regs_but_for_p (x, src, dst)
rtx x, src, dst;
{
RTX_CODE code = GET_CODE (x);
case '<': case '1': case 'c': case '2': case 'b': case '3':
{
int i;
- char *fmt = GET_RTX_FORMAT (code);
+ const char *fmt = GET_RTX_FORMAT (code);
for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
- if (fmt[i] == 'e' && ! stable_but_for_p (XEXP (x, i), src, dst))
+ if (fmt[i] == 'e'
+ && ! stable_and_no_regs_but_for_p (XEXP (x, i), src, dst))
return 0;
return 1;
}
case 'o':
- if (x == src || x == dst)
- return 1;
+ if (code == REG)
+ return x == src || x == dst;
+ /* If this is a MEM, look inside - there might be a register hidden in
+ the address of an unchanging MEM. */
+ if (code == MEM
+ && ! stable_and_no_regs_but_for_p (XEXP (x, 0), src, dst))
+ return 0;
/* fall through */
default:
return ! rtx_unstable_p (x);
}
}
-
-/* Test if regmove seems profitable for this target. Regmove is useful only
- if some common patterns are two address, i.e. require matching constraints,
- so we check that condition here. */
-
-int
-regmove_profitable_p ()
-{
-#ifdef REGISTER_CONSTRAINTS
- struct match match;
- enum machine_mode mode;
- optab tstoptab = add_optab;
- do /* check add_optab and ashl_optab */
- for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT); mode != VOIDmode;
- mode = GET_MODE_WIDER_MODE (mode))
- {
- int icode = (int) tstoptab->handlers[(int) mode].insn_code;
- rtx reg0, reg1, reg2, pat;
- int i;
-
- if (GET_MODE_BITSIZE (mode) < 32 || icode == CODE_FOR_nothing)
- continue;
- for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- if (TEST_HARD_REG_BIT (reg_class_contents[GENERAL_REGS], i))
- break;
- if (i + 2 >= FIRST_PSEUDO_REGISTER)
- break;
- reg0 = gen_rtx_REG (insn_operand_mode[icode][0], i);
- reg1 = gen_rtx_REG (insn_operand_mode[icode][1], i + 1);
- reg2 = gen_rtx_REG (insn_operand_mode[icode][2], i + 2);
- if (! (*insn_operand_predicate[icode][0]) (reg0, VOIDmode)
- || ! (*insn_operand_predicate[icode][1]) (reg1, VOIDmode)
- || ! (*insn_operand_predicate[icode][2]) (reg2, VOIDmode))
- break;
- pat = GEN_FCN (icode) (reg0, reg1, reg2);
- if (! pat)
- continue;
- if (GET_CODE (pat) == SEQUENCE)
- pat = XVECEXP (pat, 0, XVECLEN (pat, 0) - 1);
- else
- pat = make_insn_raw (pat);
- if (! single_set (pat)
- || GET_CODE (SET_SRC (single_set (pat))) != tstoptab->code)
- /* Unexpected complexity; don't need to handle this unless
- we find a machine where this occurs and regmove should
- be enabled. */
- break;
- if (find_matches (pat, &match) >= 0)
- return 1;
- break;
- }
- while (tstoptab != ashl_optab && (tstoptab = ashl_optab, 1));
-#endif /* REGISTER_CONSTRAINTS */
- return 0;
-}
OSDN Git Service
