/* Optimize jump instructions, for GNU compiler.
Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997
- 1998, 1999, 2000 Free Software Foundation, Inc.
+ 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
-This file is part of GNU CC.
+This file is part of GCC.
-GNU CC 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 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.
-GNU CC 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.
+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 GNU CC; see the file COPYING. If not, write to
-the Free Software Foundation, 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, USA. */
+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. */
-
-/* This is the jump-optimization pass of the compiler.
- It is run two or three times: once before cse, sometimes once after cse,
- and once after reload (before final).
-
- jump_optimize deletes unreachable code and labels that are not used.
- It also deletes jumps that jump to the following insn,
- and simplifies jumps around unconditional jumps and jumps
- to unconditional jumps.
+/* This is the pathetic reminder of old fame of the jump-optimization pass
+ of the compiler. Now it contains basically set of utility function to
+ operate with jumps.
Each CODE_LABEL has a count of the times it is used
stored in the LABEL_NUSES internal field, and each JUMP_INSN
formerly used them. The JUMP_LABEL info is sometimes looked
at by later passes.
- Optionally, cross-jumping can be done. Currently it is done
- only the last time (when after reload and before final).
- In fact, the code for cross-jumping now assumes that register
- allocation has been done, since it uses `rtx_renumbered_equal_p'.
-
- Jump optimization is done after cse when cse's constant-propagation
- causes jumps to become unconditional or to be deleted.
-
- Unreachable loops are not detected here, because the labels
- have references and the insns appear reachable from the labels.
- find_basic_blocks in flow.c finds and deletes such loops.
-
The subroutines delete_insn, redirect_jump, and invert_jump are used
from other passes as well. */
#include "hard-reg-set.h"
#include "regs.h"
#include "insn-config.h"
-#include "insn-flags.h"
#include "insn-attr.h"
#include "recog.h"
#include "function.h"
#include "real.h"
#include "except.h"
#include "toplev.h"
+#include "reload.h"
+#include "predict.h"
-/* ??? Eventually must record somehow the labels used by jumps
- from nested functions. */
-/* Pre-record the next or previous real insn for each label?
- No, this pass is very fast anyway. */
-/* Condense consecutive labels?
- This would make life analysis faster, maybe. */
/* Optimize jump y; x: ... y: jumpif... x?
Don't know if it is worth bothering with. */
/* Optimize two cases of conditional jump to conditional jump?
or even change what is live at any point.
So perhaps let combiner do it. */
-/* Vector indexed by uid.
- For each CODE_LABEL, index by its uid to get first unconditional jump
- that jumps to the label.
- For each JUMP_INSN, index by its uid to get the next unconditional jump
- that jumps to the same label.
- Element 0 is the start of a chain of all return insns.
- (It is safe to use element 0 because insn uid 0 is not used. */
-
-static rtx *jump_chain;
-
-/* Maximum index in jump_chain. */
-
-static int max_jump_chain;
-
-/* Set nonzero by jump_optimize if control can fall through
- to the end of the function. */
-int can_reach_end;
-
-/* Indicates whether death notes are significant in cross jump analysis.
- Normally they are not significant, because of A and B jump to C,
- and R dies in A, it must die in B. But this might not be true after
- stack register conversion, and we must compare death notes in that
- case. */
-
-static int cross_jump_death_matters = 0;
-
static int init_label_info PARAMS ((rtx));
-static void delete_barrier_successors PARAMS ((rtx));
-static void mark_all_labels PARAMS ((rtx, int));
-static rtx delete_unreferenced_labels PARAMS ((rtx));
-static void delete_noop_moves PARAMS ((rtx));
-static int calculate_can_reach_end PARAMS ((rtx, int));
+static void mark_all_labels PARAMS ((rtx));
static int duplicate_loop_exit_test PARAMS ((rtx));
-static void find_cross_jump PARAMS ((rtx, rtx, int, rtx *, rtx *));
-static void do_cross_jump PARAMS ((rtx, rtx, rtx));
-static int jump_back_p PARAMS ((rtx, rtx));
-static int tension_vector_labels PARAMS ((rtx, int));
-static void mark_jump_label PARAMS ((rtx, rtx, int, int));
static void delete_computation PARAMS ((rtx));
static void redirect_exp_1 PARAMS ((rtx *, rtx, rtx, rtx));
-static void invert_exp_1 PARAMS ((rtx, rtx));
-static void delete_from_jump_chain PARAMS ((rtx));
-static int delete_labelref_insn PARAMS ((rtx, rtx, int));
-static void mark_modified_reg PARAMS ((rtx, rtx, void *));
-static void redirect_tablejump PARAMS ((rtx, rtx));
-static void jump_optimize_1 PARAMS ((rtx, int, int, int, int, int));
+static int redirect_exp PARAMS ((rtx, rtx, rtx));
+static void invert_exp_1 PARAMS ((rtx));
+static int invert_exp PARAMS ((rtx));
static int returnjump_p_1 PARAMS ((rtx *, void *));
static void delete_prior_computation PARAMS ((rtx, rtx));
\f
-/* Main external entry point into the jump optimizer. See comments before
- jump_optimize_1 for descriptions of the arguments. */
-void
-jump_optimize (f, cross_jump, noop_moves, after_regscan)
- rtx f;
- int cross_jump;
- int noop_moves;
- int after_regscan;
-{
- jump_optimize_1 (f, cross_jump, noop_moves, after_regscan, 0, 0);
-}
-
/* Alternate entry into the jump optimizer. This entry point only rebuilds
the JUMP_LABEL field in jumping insns and REG_LABEL notes in non-jumping
instructions. */
rebuild_jump_labels (f)
rtx f;
{
- jump_optimize_1 (f, 0, 0, 0, 1, 0);
-}
-
-/* Alternate entry into the jump optimizer. Do only trivial optimizations. */
-void
-jump_optimize_minimal (f)
- rtx f;
-{
- jump_optimize_1 (f, 0, 0, 0, 0, 1);
-}
-\f
-/* Delete no-op jumps and optimize jumps to jumps
- and jumps around jumps.
- Delete unused labels and unreachable code.
-
- If CROSS_JUMP is 1, detect matching code
- before a jump and its destination and unify them.
- If CROSS_JUMP is 2, do cross-jumping, but pay attention to death notes.
-
- If NOOP_MOVES is nonzero, delete no-op move insns.
-
- If AFTER_REGSCAN is nonzero, then this jump pass is being run immediately
- after regscan, and it is safe to use regno_first_uid and regno_last_uid.
-
- If MARK_LABELS_ONLY is nonzero, then we only rebuild the jump chain
- and JUMP_LABEL field for jumping insns.
-
- If `optimize' is zero, don't change any code,
- just determine whether control drops off the end of the function.
- This case occurs when we have -W and not -O.
- It works because `delete_insn' checks the value of `optimize'
- and refrains from actually deleting when that is 0.
-
- If MINIMAL is nonzero, then we only perform trivial optimizations:
-
- * Removal of unreachable code after BARRIERs.
- * Removal of unreferenced CODE_LABELs.
- * Removal of a jump to the next instruction.
- * Removal of a conditional jump followed by an unconditional jump
- to the same target as the conditional jump.
- * Simplify a conditional jump around an unconditional jump.
- * Simplify a jump to a jump.
- * Delete extraneous line number notes.
- */
-
-static void
-jump_optimize_1 (f, cross_jump, noop_moves, after_regscan,
- mark_labels_only, minimal)
- rtx f;
- int cross_jump;
- int noop_moves;
- int after_regscan;
- int mark_labels_only;
- int minimal;
-{
- register rtx insn, next;
- int changed;
- int old_max_reg;
- int first = 1;
+ rtx insn;
int max_uid = 0;
- rtx last_insn;
- cross_jump_death_matters = (cross_jump == 2);
max_uid = init_label_info (f) + 1;
- /* If we are performing cross jump optimizations, then initialize
- tables mapping UIDs to EH regions to avoid incorrect movement
- of insns from one EH region to another. */
- if (flag_exceptions && cross_jump)
- init_insn_eh_region (f, max_uid);
-
- if (! mark_labels_only)
- delete_barrier_successors (f);
-
- /* Leave some extra room for labels and duplicate exit test insns
- we make. */
- max_jump_chain = max_uid * 14 / 10;
- jump_chain = (rtx *) xcalloc (max_jump_chain, sizeof (rtx));
-
- mark_all_labels (f, cross_jump);
+ mark_all_labels (f);
/* Keep track of labels used from static data; we don't track them
closely enough to delete them here, so make sure their reference
for (insn = forced_labels; insn; insn = XEXP (insn, 1))
if (GET_CODE (XEXP (insn, 0)) == CODE_LABEL)
LABEL_NUSES (XEXP (insn, 0))++;
-
- check_exception_handler_labels ();
-
- /* Keep track of labels used for marking handlers for exception
- regions; they cannot usually be deleted. */
-
- for (insn = exception_handler_labels; insn; insn = XEXP (insn, 1))
- LABEL_NUSES (XEXP (insn, 0))++;
-
- /* Quit now if we just wanted to rebuild the JUMP_LABEL and REG_LABEL
- notes and recompute LABEL_NUSES. */
- if (mark_labels_only)
- goto end;
-
- if (! minimal)
- exception_optimize ();
-
- last_insn = delete_unreferenced_labels (f);
-
- if (noop_moves)
- delete_noop_moves (f);
-
- /* If we haven't yet gotten to reload and we have just run regscan,
- delete any insn that sets a register that isn't used elsewhere.
- This helps some of the optimizations below by having less insns
- being jumped around. */
-
- if (optimize && ! reload_completed && after_regscan)
- for (insn = f; insn; insn = next)
- {
- rtx set = single_set (insn);
-
- next = NEXT_INSN (insn);
-
- if (set && GET_CODE (SET_DEST (set)) == REG
- && REGNO (SET_DEST (set)) >= FIRST_PSEUDO_REGISTER
- && REGNO_FIRST_UID (REGNO (SET_DEST (set))) == INSN_UID (insn)
- /* We use regno_last_note_uid so as not to delete the setting
- of a reg that's used in notes. A subsequent optimization
- might arrange to use that reg for real. */
- && REGNO_LAST_NOTE_UID (REGNO (SET_DEST (set))) == INSN_UID (insn)
- && ! side_effects_p (SET_SRC (set))
- && ! find_reg_note (insn, REG_RETVAL, 0)
- /* An ADDRESSOF expression can turn into a use of the internal arg
- pointer, so do not delete the initialization of the internal
- arg pointer yet. If it is truly dead, flow will delete the
- initializing insn. */
- && SET_DEST (set) != current_function_internal_arg_pointer)
- delete_insn (insn);
- }
-
- /* Now iterate optimizing jumps until nothing changes over one pass. */
- changed = 1;
- old_max_reg = max_reg_num ();
- while (changed)
+}
+\f
+/* Some old code expects exactly one BARRIER as the NEXT_INSN of a
+ non-fallthru insn. This is not generally true, as multiple barriers
+ may have crept in, or the BARRIER may be separated from the last
+ real insn by one or more NOTEs.
+
+ This simple pass moves barriers and removes duplicates so that the
+ old code is happy.
+ */
+void
+cleanup_barriers ()
+{
+ rtx insn, next, prev;
+ for (insn = get_insns (); insn; insn = next)
{
- changed = 0;
-
- for (insn = f; insn; insn = next)
+ next = NEXT_INSN (insn);
+ if (GET_CODE (insn) == BARRIER)
{
- rtx reallabelprev;
- rtx temp, temp1, temp2 = NULL_RTX;
- rtx temp4 ATTRIBUTE_UNUSED;
- rtx nlabel;
- int this_is_simplejump, this_is_condjump;
- int this_is_condjump_in_parallel;
-
- next = NEXT_INSN (insn);
-
- /* See if this is a NOTE_INSN_LOOP_BEG followed by an unconditional
- jump. Try to optimize by duplicating the loop exit test if so.
- This is only safe immediately after regscan, because it uses
- the values of regno_first_uid and regno_last_uid. */
- if (after_regscan && GET_CODE (insn) == NOTE
- && NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG
- && (temp1 = next_nonnote_insn (insn)) != 0
- && simplejump_p (temp1))
- {
- temp = PREV_INSN (insn);
- if (duplicate_loop_exit_test (insn))
- {
- changed = 1;
- next = NEXT_INSN (temp);
- continue;
- }
- }
-
- if (GET_CODE (insn) != JUMP_INSN)
- continue;
-
- this_is_simplejump = simplejump_p (insn);
- this_is_condjump = condjump_p (insn);
- this_is_condjump_in_parallel = condjump_in_parallel_p (insn);
-
- /* Tension the labels in dispatch tables. */
-
- if (GET_CODE (PATTERN (insn)) == ADDR_VEC)
- changed |= tension_vector_labels (PATTERN (insn), 0);
- if (GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC)
- changed |= tension_vector_labels (PATTERN (insn), 1);
-
- /* See if this jump goes to another jump and redirect if so. */
- nlabel = follow_jumps (JUMP_LABEL (insn));
- if (nlabel != JUMP_LABEL (insn))
- changed |= redirect_jump (insn, nlabel);
-
- if (! optimize || minimal)
- continue;
-
- /* If a dispatch table always goes to the same place,
- get rid of it and replace the insn that uses it. */
-
- if (GET_CODE (PATTERN (insn)) == ADDR_VEC
- || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC)
- {
- int i;
- rtx pat = PATTERN (insn);
- int diff_vec_p = GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC;
- int len = XVECLEN (pat, diff_vec_p);
- rtx dispatch = prev_real_insn (insn);
- rtx set;
-
- for (i = 0; i < len; i++)
- if (XEXP (XVECEXP (pat, diff_vec_p, i), 0)
- != XEXP (XVECEXP (pat, diff_vec_p, 0), 0))
- break;
-
- if (i == len
- && dispatch != 0
- && GET_CODE (dispatch) == JUMP_INSN
- && JUMP_LABEL (dispatch) != 0
- /* Don't mess with a casesi insn.
- XXX according to the comment before computed_jump_p(),
- all casesi insns should be a parallel of the jump
- and a USE of a LABEL_REF. */
- && ! ((set = single_set (dispatch)) != NULL
- && (GET_CODE (SET_SRC (set)) == IF_THEN_ELSE))
- && next_real_insn (JUMP_LABEL (dispatch)) == insn)
- {
- redirect_tablejump (dispatch,
- XEXP (XVECEXP (pat, diff_vec_p, 0), 0));
- changed = 1;
- }
- }
-
- reallabelprev = prev_active_insn (JUMP_LABEL (insn));
-
- /* Detect jump to following insn. */
- if (reallabelprev == insn && this_is_condjump)
- {
- next = next_real_insn (JUMP_LABEL (insn));
- delete_jump (insn);
-
- /* Remove the "inactive" but "real" insns (i.e. uses and
- clobbers) in between here and there. */
- temp = insn;
- while ((temp = next_real_insn (temp)) != next)
- delete_insn (temp);
-
- changed = 1;
- continue;
- }
-
- /* Detect a conditional jump going to the same place
- as an immediately following unconditional jump. */
- else if (this_is_condjump
- && (temp = next_active_insn (insn)) != 0
- && simplejump_p (temp)
- && (next_active_insn (JUMP_LABEL (insn))
- == next_active_insn (JUMP_LABEL (temp))))
- {
- /* Don't mess up test coverage analysis. */
- temp2 = temp;
- if (flag_test_coverage && !reload_completed)
- for (temp2 = insn; temp2 != temp; temp2 = NEXT_INSN (temp2))
- if (GET_CODE (temp2) == NOTE && NOTE_LINE_NUMBER (temp2) > 0)
- break;
-
- if (temp2 == temp)
- {
- delete_jump (insn);
- changed = 1;
- continue;
- }
- }
-
- /* Detect a conditional jump jumping over an unconditional jump. */
-
- else if ((this_is_condjump || this_is_condjump_in_parallel)
- && ! this_is_simplejump
- && reallabelprev != 0
- && GET_CODE (reallabelprev) == JUMP_INSN
- && prev_active_insn (reallabelprev) == insn
- && no_labels_between_p (insn, reallabelprev)
- && simplejump_p (reallabelprev))
- {
- /* When we invert the unconditional jump, we will be
- decrementing the usage count of its old label.
- Make sure that we don't delete it now because that
- might cause the following code to be deleted. */
- rtx prev_uses = prev_nonnote_insn (reallabelprev);
- rtx prev_label = JUMP_LABEL (insn);
-
- if (prev_label)
- ++LABEL_NUSES (prev_label);
-
- if (invert_jump (insn, JUMP_LABEL (reallabelprev)))
- {
- /* It is very likely that if there are USE insns before
- this jump, they hold REG_DEAD notes. These REG_DEAD
- notes are no longer valid due to this optimization,
- and will cause the life-analysis that following passes
- (notably delayed-branch scheduling) to think that
- these registers are dead when they are not.
-
- To prevent this trouble, we just remove the USE insns
- from the insn chain. */
-
- while (prev_uses && GET_CODE (prev_uses) == INSN
- && GET_CODE (PATTERN (prev_uses)) == USE)
- {
- rtx useless = prev_uses;
- prev_uses = prev_nonnote_insn (prev_uses);
- delete_insn (useless);
- }
-
- delete_insn (reallabelprev);
- changed = 1;
- }
-
- /* We can now safely delete the label if it is unreferenced
- since the delete_insn above has deleted the BARRIER. */
- if (prev_label && --LABEL_NUSES (prev_label) == 0)
- delete_insn (prev_label);
-
- next = NEXT_INSN (insn);
- }
-
- /* If we have an unconditional jump preceded by a USE, try to put
- the USE before the target and jump there. This simplifies many
- of the optimizations below since we don't have to worry about
- dealing with these USE insns. We only do this if the label
- being branch to already has the identical USE or if code
- never falls through to that label. */
-
- else if (this_is_simplejump
- && (temp = prev_nonnote_insn (insn)) != 0
- && GET_CODE (temp) == INSN
- && GET_CODE (PATTERN (temp)) == USE
- && (temp1 = prev_nonnote_insn (JUMP_LABEL (insn))) != 0
- && (GET_CODE (temp1) == BARRIER
- || (GET_CODE (temp1) == INSN
- && rtx_equal_p (PATTERN (temp), PATTERN (temp1))))
- /* Don't do this optimization if we have a loop containing
- only the USE instruction, and the loop start label has
- a usage count of 1. This is because we will redo this
- optimization everytime through the outer loop, and jump
- opt will never exit. */
- && ! ((temp2 = prev_nonnote_insn (temp)) != 0
- && temp2 == JUMP_LABEL (insn)
- && LABEL_NUSES (temp2) == 1))
- {
- if (GET_CODE (temp1) == BARRIER)
- {
- emit_insn_after (PATTERN (temp), temp1);
- temp1 = NEXT_INSN (temp1);
- }
-
- delete_insn (temp);
- redirect_jump (insn, get_label_before (temp1));
- reallabelprev = prev_real_insn (temp1);
- changed = 1;
- next = NEXT_INSN (insn);
- }
-
-#ifdef HAVE_trap
- /* Detect a conditional jump jumping over an unconditional trap. */
- if (HAVE_trap
- && this_is_condjump && ! this_is_simplejump
- && reallabelprev != 0
- && GET_CODE (reallabelprev) == INSN
- && GET_CODE (PATTERN (reallabelprev)) == TRAP_IF
- && TRAP_CONDITION (PATTERN (reallabelprev)) == const_true_rtx
- && prev_active_insn (reallabelprev) == insn
- && no_labels_between_p (insn, reallabelprev)
- && (temp2 = get_condition (insn, &temp4))
- && can_reverse_comparison_p (temp2, insn))
- {
- rtx new = gen_cond_trap (reverse_condition (GET_CODE (temp2)),
- XEXP (temp2, 0), XEXP (temp2, 1),
- TRAP_CODE (PATTERN (reallabelprev)));
+ prev = prev_nonnote_insn (insn);
+ if (GET_CODE (prev) == BARRIER)
+ delete_barrier (insn);
+ else if (prev != PREV_INSN (insn))
+ reorder_insns (insn, insn, prev);
+ }
+ }
+}
+\f
+void
+copy_loop_headers (f)
+ rtx f;
+{
+ rtx insn, next;
+ /* Now iterate optimizing jumps until nothing changes over one pass. */
+ for (insn = f; insn; insn = next)
+ {
+ rtx temp, temp1;
- if (new)
- {
- emit_insn_before (new, temp4);
- delete_insn (reallabelprev);
- delete_jump (insn);
- changed = 1;
- continue;
- }
- }
- /* Detect a jump jumping to an unconditional trap. */
- else if (HAVE_trap && this_is_condjump
- && (temp = next_active_insn (JUMP_LABEL (insn)))
- && GET_CODE (temp) == INSN
- && GET_CODE (PATTERN (temp)) == TRAP_IF
- && (this_is_simplejump
- || (temp2 = get_condition (insn, &temp4))))
- {
- rtx tc = TRAP_CONDITION (PATTERN (temp));
+ next = NEXT_INSN (insn);
- if (tc == const_true_rtx
- || (! this_is_simplejump && rtx_equal_p (temp2, tc)))
- {
- rtx new;
- /* Replace an unconditional jump to a trap with a trap. */
- if (this_is_simplejump)
- {
- emit_barrier_after (emit_insn_before (gen_trap (), insn));
- delete_jump (insn);
- changed = 1;
- continue;
- }
- new = gen_cond_trap (GET_CODE (temp2), XEXP (temp2, 0),
- XEXP (temp2, 1),
- TRAP_CODE (PATTERN (temp)));
- if (new)
- {
- emit_insn_before (new, temp4);
- delete_jump (insn);
- changed = 1;
- continue;
- }
- }
- /* If the trap condition and jump condition are mutually
- exclusive, redirect the jump to the following insn. */
- else if (GET_RTX_CLASS (GET_CODE (tc)) == '<'
- && ! this_is_simplejump
- && swap_condition (GET_CODE (temp2)) == GET_CODE (tc)
- && rtx_equal_p (XEXP (tc, 0), XEXP (temp2, 0))
- && rtx_equal_p (XEXP (tc, 1), XEXP (temp2, 1))
- && redirect_jump (insn, get_label_after (temp)))
- {
- changed = 1;
- continue;
- }
- }
-#endif
- else
+ /* See if this is a NOTE_INSN_LOOP_BEG followed by an unconditional
+ jump. Try to optimize by duplicating the loop exit test if so.
+ This is only safe immediately after regscan, because it uses
+ the values of regno_first_uid and regno_last_uid. */
+ if (GET_CODE (insn) == NOTE
+ && NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG
+ && (temp1 = next_nonnote_insn (insn)) != 0
+ && any_uncondjump_p (temp1) && onlyjump_p (temp1))
+ {
+ temp = PREV_INSN (insn);
+ if (duplicate_loop_exit_test (insn))
{
- /* Now that the jump has been tensioned,
- try cross jumping: check for identical code
- before the jump and before its target label. */
-
- /* First, cross jumping of conditional jumps: */
-
- if (cross_jump && condjump_p (insn))
- {
- rtx newjpos, newlpos;
- rtx x = prev_real_insn (JUMP_LABEL (insn));
-
- /* A conditional jump may be crossjumped
- only if the place it jumps to follows
- an opposing jump that comes back here. */
-
- if (x != 0 && ! jump_back_p (x, insn))
- /* We have no opposing jump;
- cannot cross jump this insn. */
- x = 0;
-
- newjpos = 0;
- /* TARGET is nonzero if it is ok to cross jump
- to code before TARGET. If so, see if matches. */
- if (x != 0)
- find_cross_jump (insn, x, 2,
- &newjpos, &newlpos);
-
- if (newjpos != 0)
- {
- do_cross_jump (insn, newjpos, newlpos);
- /* Make the old conditional jump
- into an unconditional one. */
- SET_SRC (PATTERN (insn))
- = gen_rtx_LABEL_REF (VOIDmode, JUMP_LABEL (insn));
- INSN_CODE (insn) = -1;
- emit_barrier_after (insn);
- /* Add to jump_chain unless this is a new label
- whose UID is too large. */
- if (INSN_UID (JUMP_LABEL (insn)) < max_jump_chain)
- {
- jump_chain[INSN_UID (insn)]
- = jump_chain[INSN_UID (JUMP_LABEL (insn))];
- jump_chain[INSN_UID (JUMP_LABEL (insn))] = insn;
- }
- changed = 1;
- next = insn;
- }
- }
-
- /* Cross jumping of unconditional jumps:
- a few differences. */
-
- if (cross_jump && simplejump_p (insn))
- {
- rtx newjpos, newlpos;
- rtx target;
-
- newjpos = 0;
-
- /* TARGET is nonzero if it is ok to cross jump
- to code before TARGET. If so, see if matches. */
- find_cross_jump (insn, JUMP_LABEL (insn), 1,
- &newjpos, &newlpos);
-
- /* If cannot cross jump to code before the label,
- see if we can cross jump to another jump to
- the same label. */
- /* Try each other jump to this label. */
- if (INSN_UID (JUMP_LABEL (insn)) < max_uid)
- for (target = jump_chain[INSN_UID (JUMP_LABEL (insn))];
- target != 0 && newjpos == 0;
- target = jump_chain[INSN_UID (target)])
- if (target != insn
- && JUMP_LABEL (target) == JUMP_LABEL (insn)
- /* Ignore TARGET if it's deleted. */
- && ! INSN_DELETED_P (target))
- find_cross_jump (insn, target, 2,
- &newjpos, &newlpos);
-
- if (newjpos != 0)
- {
- do_cross_jump (insn, newjpos, newlpos);
- changed = 1;
- next = insn;
- }
- }
-
- /* This code was dead in the previous jump.c! */
- if (cross_jump && GET_CODE (PATTERN (insn)) == RETURN)
- {
- /* Return insns all "jump to the same place"
- so we can cross-jump between any two of them. */
-
- rtx newjpos, newlpos, target;
-
- newjpos = 0;
-
- /* If cannot cross jump to code before the label,
- see if we can cross jump to another jump to
- the same label. */
- /* Try each other jump to this label. */
- for (target = jump_chain[0];
- target != 0 && newjpos == 0;
- target = jump_chain[INSN_UID (target)])
- if (target != insn
- && ! INSN_DELETED_P (target)
- && GET_CODE (PATTERN (target)) == RETURN)
- find_cross_jump (insn, target, 2,
- &newjpos, &newlpos);
-
- if (newjpos != 0)
- {
- do_cross_jump (insn, newjpos, newlpos);
- changed = 1;
- next = insn;
- }
- }
+ next = NEXT_INSN (temp);
}
}
-
- first = 0;
}
+}
+void
+purge_line_number_notes (f)
+ rtx f;
+{
+ rtx last_note = 0;
+ rtx insn;
/* Delete extraneous line number notes.
Note that two consecutive notes for different lines are not really
extraneous. There should be some indication where that line belonged,
even if it became empty. */
- {
- rtx last_note = 0;
-
- for (insn = f; insn; insn = NEXT_INSN (insn))
- if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) >= 0)
- {
- /* Delete this note if it is identical to previous note. */
- if (last_note
- && NOTE_SOURCE_FILE (insn) == NOTE_SOURCE_FILE (last_note)
- && NOTE_LINE_NUMBER (insn) == NOTE_LINE_NUMBER (last_note))
- {
- delete_insn (insn);
- continue;
- }
-
- last_note = insn;
- }
- }
-
- /* CAN_REACH_END is persistent for each function. Once set it should
- not be cleared. This is especially true for the case where we
- delete the NOTE_FUNCTION_END note. CAN_REACH_END is cleared by
- the front-end before compiling each function. */
- if (! minimal && calculate_can_reach_end (last_insn, optimize != 0))
- can_reach_end = 1;
+ for (insn = f; insn; insn = NEXT_INSN (insn))
+ if (GET_CODE (insn) == NOTE)
+ {
+ if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_BEG)
+ /* Any previous line note was for the prologue; gdb wants a new
+ note after the prologue even if it is for the same line. */
+ last_note = NULL_RTX;
+ else if (NOTE_LINE_NUMBER (insn) >= 0)
+ {
+ /* Delete this note if it is identical to previous note. */
+ if (last_note
+ && NOTE_SOURCE_FILE (insn) == NOTE_SOURCE_FILE (last_note)
+ && NOTE_LINE_NUMBER (insn) == NOTE_LINE_NUMBER (last_note))
+ {
+ delete_related_insns (insn);
+ continue;
+ }
-end:
- /* Clean up. */
- free (jump_chain);
- jump_chain = 0;
+ last_note = insn;
+ }
+ }
}
\f
/* Initialize LABEL_NUSES and JUMP_LABEL fields. Delete any REG_LABEL
return largest_uid;
}
-/* Delete insns following barriers, up to next label.
-
- Also delete no-op jumps created by gcse. */
-
-static void
-delete_barrier_successors (f)
- rtx f;
-{
- rtx insn;
-
- for (insn = f; insn;)
- {
- if (GET_CODE (insn) == BARRIER)
- {
- insn = NEXT_INSN (insn);
-
- never_reached_warning (insn);
-
- while (insn != 0 && GET_CODE (insn) != CODE_LABEL)
- {
- if (GET_CODE (insn) == NOTE
- && NOTE_LINE_NUMBER (insn) != NOTE_INSN_FUNCTION_END)
- insn = NEXT_INSN (insn);
- else
- insn = delete_insn (insn);
- }
- /* INSN is now the code_label. */
- }
-
- /* Also remove (set (pc) (pc)) insns which can be created by
- gcse. We eliminate such insns now to avoid having them
- cause problems later. */
- else if (GET_CODE (insn) == JUMP_INSN
- && GET_CODE (PATTERN (insn)) == SET
- && SET_SRC (PATTERN (insn)) == pc_rtx
- && SET_DEST (PATTERN (insn)) == pc_rtx)
- insn = delete_insn (insn);
-
- else
- insn = NEXT_INSN (insn);
- }
-}
-
/* Mark the label each jump jumps to.
- Combine consecutive labels, and count uses of labels.
-
- For each label, make a chain (using `jump_chain')
- of all the *unconditional* jumps that jump to it;
- also make a chain of all returns.
-
- CROSS_JUMP indicates whether we are doing cross jumping
- and if we are whether we will be paying attention to
- death notes or not. */
+ Combine consecutive labels, and count uses of labels. */
static void
-mark_all_labels (f, cross_jump)
+mark_all_labels (f)
rtx f;
- int cross_jump;
{
rtx insn;
for (insn = f; insn; insn = NEXT_INSN (insn))
- if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
+ if (INSN_P (insn))
{
if (GET_CODE (insn) == CALL_INSN
&& GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
{
- mark_all_labels (XEXP (PATTERN (insn), 0), cross_jump);
- mark_all_labels (XEXP (PATTERN (insn), 1), cross_jump);
- mark_all_labels (XEXP (PATTERN (insn), 2), cross_jump);
+ mark_all_labels (XEXP (PATTERN (insn), 0));
+ mark_all_labels (XEXP (PATTERN (insn), 1));
+ mark_all_labels (XEXP (PATTERN (insn), 2));
+
+ /* Canonicalize the tail recursion label attached to the
+ CALL_PLACEHOLDER insn. */
+ if (XEXP (PATTERN (insn), 3))
+ {
+ rtx label_ref = gen_rtx_LABEL_REF (VOIDmode,
+ XEXP (PATTERN (insn), 3));
+ mark_jump_label (label_ref, insn, 0);
+ XEXP (PATTERN (insn), 3) = XEXP (label_ref, 0);
+ }
+
continue;
}
-
- mark_jump_label (PATTERN (insn), insn, cross_jump, 0);
+
+ mark_jump_label (PATTERN (insn), insn, 0);
if (! INSN_DELETED_P (insn) && GET_CODE (insn) == JUMP_INSN)
{
- if (JUMP_LABEL (insn) != 0 && simplejump_p (insn))
- {
- jump_chain[INSN_UID (insn)]
- = jump_chain[INSN_UID (JUMP_LABEL (insn))];
- jump_chain[INSN_UID (JUMP_LABEL (insn))] = insn;
- }
- if (GET_CODE (PATTERN (insn)) == RETURN)
+ /* When we know the LABEL_REF contained in a REG used in
+ an indirect jump, we'll have a REG_LABEL note so that
+ flow can tell where it's going. */
+ if (JUMP_LABEL (insn) == 0)
{
- jump_chain[INSN_UID (insn)] = jump_chain[0];
- jump_chain[0] = insn;
+ rtx label_note = find_reg_note (insn, REG_LABEL, NULL_RTX);
+ if (label_note)
+ {
+ /* But a LABEL_REF around the REG_LABEL note, so
+ that we can canonicalize it. */
+ rtx label_ref = gen_rtx_LABEL_REF (VOIDmode,
+ XEXP (label_note, 0));
+
+ mark_jump_label (label_ref, insn, 0);
+ XEXP (label_note, 0) = XEXP (label_ref, 0);
+ JUMP_LABEL (insn) = XEXP (label_note, 0);
+ }
}
}
}
}
-/* Delete all labels already not referenced.
- Also find and return the last insn. */
-
-static rtx
-delete_unreferenced_labels (f)
- rtx f;
-{
- rtx final = NULL_RTX;
- rtx insn;
-
- for (insn = f; insn; )
- {
- if (GET_CODE (insn) == CODE_LABEL
- && LABEL_NUSES (insn) == 0
- && LABEL_ALTERNATE_NAME (insn) == NULL)
- insn = delete_insn (insn);
- else
- {
- final = insn;
- insn = NEXT_INSN (insn);
- }
- }
-
- return final;
-}
-
-/* Delete various simple forms of moves which have no necessary
- side effect. */
-
-static void
-delete_noop_moves (f)
- rtx f;
-{
- rtx insn, next;
-
- for (insn = f; insn; )
- {
- next = NEXT_INSN (insn);
-
- if (GET_CODE (insn) == INSN)
- {
- register rtx body = PATTERN (insn);
-
- /* Detect and delete no-op move instructions
- resulting from not allocating a parameter in a register. */
-
- if (GET_CODE (body) == SET
- && (SET_DEST (body) == SET_SRC (body)
- || (GET_CODE (SET_DEST (body)) == MEM
- && GET_CODE (SET_SRC (body)) == MEM
- && rtx_equal_p (SET_SRC (body), SET_DEST (body))))
- && ! (GET_CODE (SET_DEST (body)) == MEM
- && MEM_VOLATILE_P (SET_DEST (body)))
- && ! (GET_CODE (SET_SRC (body)) == MEM
- && MEM_VOLATILE_P (SET_SRC (body))))
- delete_computation (insn);
-
- /* Detect and ignore no-op move instructions
- resulting from smart or fortuitous register allocation. */
-
- else if (GET_CODE (body) == SET)
- {
- int sreg = true_regnum (SET_SRC (body));
- int dreg = true_regnum (SET_DEST (body));
-
- if (sreg == dreg && sreg >= 0)
- delete_insn (insn);
- else if (sreg >= 0 && dreg >= 0)
- {
- rtx trial;
- rtx tem = find_equiv_reg (NULL_RTX, insn, 0,
- sreg, NULL_PTR, dreg,
- GET_MODE (SET_SRC (body)));
-
- if (tem != 0
- && GET_MODE (tem) == GET_MODE (SET_DEST (body)))
- {
- /* DREG may have been the target of a REG_DEAD note in
- the insn which makes INSN redundant. If so, reorg
- would still think it is dead. So search for such a
- note and delete it if we find it. */
- if (! find_regno_note (insn, REG_UNUSED, dreg))
- for (trial = prev_nonnote_insn (insn);
- trial && GET_CODE (trial) != CODE_LABEL;
- trial = prev_nonnote_insn (trial))
- if (find_regno_note (trial, REG_DEAD, dreg))
- {
- remove_death (dreg, trial);
- break;
- }
-
- /* Deleting insn could lose a death-note for SREG. */
- if ((trial = find_regno_note (insn, REG_DEAD, sreg)))
- {
- /* Change this into a USE so that we won't emit
- code for it, but still can keep the note. */
- PATTERN (insn)
- = gen_rtx_USE (VOIDmode, XEXP (trial, 0));
- INSN_CODE (insn) = -1;
- /* Remove all reg notes but the REG_DEAD one. */
- REG_NOTES (insn) = trial;
- XEXP (trial, 1) = NULL_RTX;
- }
- else
- delete_insn (insn);
- }
- }
- else if (dreg >= 0 && CONSTANT_P (SET_SRC (body))
- && find_equiv_reg (SET_SRC (body), insn, 0, dreg,
- NULL_PTR, 0,
- GET_MODE (SET_DEST (body))))
- {
- /* This handles the case where we have two consecutive
- assignments of the same constant to pseudos that didn't
- get a hard reg. Each SET from the constant will be
- converted into a SET of the spill register and an
- output reload will be made following it. This produces
- two loads of the same constant into the same spill
- register. */
-
- rtx in_insn = insn;
-
- /* Look back for a death note for the first reg.
- If there is one, it is no longer accurate. */
- while (in_insn && GET_CODE (in_insn) != CODE_LABEL)
- {
- if ((GET_CODE (in_insn) == INSN
- || GET_CODE (in_insn) == JUMP_INSN)
- && find_regno_note (in_insn, REG_DEAD, dreg))
- {
- remove_death (dreg, in_insn);
- break;
- }
- in_insn = PREV_INSN (in_insn);
- }
-
- /* Delete the second load of the value. */
- delete_insn (insn);
- }
- }
- else if (GET_CODE (body) == PARALLEL)
- {
- /* If each part is a set between two identical registers or
- a USE or CLOBBER, delete the insn. */
- int i, sreg, dreg;
- rtx tem;
-
- for (i = XVECLEN (body, 0) - 1; i >= 0; i--)
- {
- tem = XVECEXP (body, 0, i);
- if (GET_CODE (tem) == USE || GET_CODE (tem) == CLOBBER)
- continue;
-
- if (GET_CODE (tem) != SET
- || (sreg = true_regnum (SET_SRC (tem))) < 0
- || (dreg = true_regnum (SET_DEST (tem))) < 0
- || dreg != sreg)
- break;
- }
-
- if (i < 0)
- delete_insn (insn);
- }
- /* Also delete insns to store bit fields if they are no-ops. */
- /* Not worth the hair to detect this in the big-endian case. */
- else if (! BYTES_BIG_ENDIAN
- && GET_CODE (body) == SET
- && GET_CODE (SET_DEST (body)) == ZERO_EXTRACT
- && XEXP (SET_DEST (body), 2) == const0_rtx
- && XEXP (SET_DEST (body), 0) == SET_SRC (body)
- && ! (GET_CODE (SET_SRC (body)) == MEM
- && MEM_VOLATILE_P (SET_SRC (body))))
- delete_insn (insn);
- }
- insn = next;
- }
-}
-
-/* See if there is still a NOTE_INSN_FUNCTION_END in this function.
- If so indicate that this function can drop off the end by returning
- 1, else return 0.
-
- CHECK_DELETED indicates whether we must check if the note being
- searched for has the deleted flag set.
-
- DELETE_FINAL_NOTE indicates whether we should delete the note
- if we find it. */
-
-static int
-calculate_can_reach_end (last, delete_final_note)
- rtx last;
- int delete_final_note;
-{
- rtx insn = last;
- int n_labels = 1;
-
- while (insn != NULL_RTX)
- {
- int ok = 0;
-
- /* One label can follow the end-note: the return label. */
- if (GET_CODE (insn) == CODE_LABEL && n_labels-- > 0)
- ok = 1;
- /* Ordinary insns can follow it if returning a structure. */
- else if (GET_CODE (insn) == INSN)
- ok = 1;
- /* If machine uses explicit RETURN insns, no epilogue,
- then one of them follows the note. */
- else if (GET_CODE (insn) == JUMP_INSN
- && GET_CODE (PATTERN (insn)) == RETURN)
- ok = 1;
- /* A barrier can follow the return insn. */
- else if (GET_CODE (insn) == BARRIER)
- ok = 1;
- /* Other kinds of notes can follow also. */
- else if (GET_CODE (insn) == NOTE
- && NOTE_LINE_NUMBER (insn) != NOTE_INSN_FUNCTION_END)
- ok = 1;
-
- if (ok != 1)
- break;
-
- insn = PREV_INSN (insn);
- }
-
- /* See if we backed up to the appropriate type of note. */
- if (insn != NULL_RTX
- && GET_CODE (insn) == NOTE
- && NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_END)
- {
- if (delete_final_note)
- delete_insn (insn);
- return 1;
- }
-
- return 0;
-}
-
/* LOOP_START is a NOTE_INSN_LOOP_BEG note that is followed by an unconditional
jump. Assume that this unconditional jump is to the exit test code. If
the code is sufficiently simple, make a copy of it before INSN,
rtx lastexit;
int max_reg = max_reg_num ();
rtx *reg_map = 0;
+ rtx loop_pre_header_label;
/* Scan the exit code. We do not perform this optimization if any insn:
is a CODE_LABEL
has a REG_RETVAL or REG_LIBCALL note (hard to adjust)
is a NOTE_INSN_LOOP_BEG because this means we have a nested loop
- is a NOTE_INSN_BLOCK_{BEG,END} because duplicating these notes
- is not valid.
We also do not do this if we find an insn with ASM_OPERANDS. While
this restriction should not be necessary, copying an insn with
case CALL_INSN:
return 0;
case NOTE:
- /* We could be in front of the wrong NOTE_INSN_LOOP_END if there is
- a jump immediately after the loop start that branches outside
- the loop but within an outer loop, near the exit test.
- If we copied this exit test and created a phony
- NOTE_INSN_LOOP_VTOP, this could make instructions immediately
- before the exit test look like these could be safely moved
- out of the loop even if they actually may be never executed.
- This can be avoided by checking here for NOTE_INSN_LOOP_CONT. */
-
- if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG
- || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_CONT)
- return 0;
if (optimize < 2
&& (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG
reg_map[REGNO (reg)] = gen_reg_rtx (GET_MODE (reg));
}
}
+ loop_pre_header_label = gen_label_rtx ();
/* Now copy each insn. */
for (insn = exitcode; insn != lastexit; insn = NEXT_INSN (insn))
NOTE_SOURCE_FILE (copy) = NOTE_SOURCE_FILE (insn);
}
break;
-
+
case INSN:
copy = emit_insn_before (copy_insn (PATTERN (insn)), loop_start);
if (reg_map)
replace_regs (PATTERN (copy), reg_map, max_reg, 1);
-
- mark_jump_label (PATTERN (copy), copy, 0, 0);
-
+
+ mark_jump_label (PATTERN (copy), copy, 0);
+ INSN_SCOPE (copy) = INSN_SCOPE (insn);
+
/* Copy all REG_NOTES except REG_LABEL since mark_jump_label will
make them. */
for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
if (reg_map && REG_NOTES (copy))
replace_regs (REG_NOTES (copy), reg_map, max_reg, 1);
break;
-
+
case JUMP_INSN:
- copy = emit_jump_insn_before (copy_insn (PATTERN (insn)), loop_start);
+ copy = emit_jump_insn_before (copy_insn (PATTERN (insn)),
+ loop_start);
+ INSN_SCOPE (copy) = INSN_SCOPE (insn);
if (reg_map)
replace_regs (PATTERN (copy), reg_map, max_reg, 1);
- mark_jump_label (PATTERN (copy), copy, 0, 0);
+ mark_jump_label (PATTERN (copy), copy, 0);
if (REG_NOTES (insn))
{
REG_NOTES (copy) = copy_insn_1 (REG_NOTES (insn));
if (reg_map)
replace_regs (REG_NOTES (copy), reg_map, max_reg, 1);
}
-
- /* If this is a simple jump, add it to the jump chain. */
-
- if (INSN_UID (copy) < max_jump_chain && JUMP_LABEL (copy)
- && simplejump_p (copy))
+
+ /* Predict conditional jump that do make loop looping as taken.
+ Other jumps are probably exit conditions, so predict
+ them as untaken. */
+ if (any_condjump_p (copy))
{
- jump_chain[INSN_UID (copy)]
- = jump_chain[INSN_UID (JUMP_LABEL (copy))];
- jump_chain[INSN_UID (JUMP_LABEL (copy))] = copy;
+ rtx label = JUMP_LABEL (copy);
+ if (label)
+ {
+ /* The jump_insn after loop_start should be followed
+ by barrier and loopback label. */
+ if (prev_nonnote_insn (label)
+ && (prev_nonnote_insn (prev_nonnote_insn (label))
+ == next_nonnote_insn (loop_start)))
+ {
+ predict_insn_def (copy, PRED_LOOP_HEADER, TAKEN);
+ /* To keep pre-header, we need to redirect all loop
+ entrances before the LOOP_BEG note. */
+ redirect_jump (copy, loop_pre_header_label, 0);
+ }
+ else
+ predict_insn_def (copy, PRED_LOOP_HEADER, NOT_TAKEN);
+ }
}
break;
-
+
default:
abort ();
}
if (! first_copy)
first_copy = copy;
- mark_jump_label (PATTERN (copy), copy, 0, 0);
- if (INSN_UID (copy) < max_jump_chain
- && INSN_UID (JUMP_LABEL (copy)) < max_jump_chain)
- {
- jump_chain[INSN_UID (copy)]
- = jump_chain[INSN_UID (JUMP_LABEL (copy))];
- jump_chain[INSN_UID (JUMP_LABEL (copy))] = copy;
- }
- emit_barrier_before (loop_start);
- }
-
- /* Now scan from the first insn we copied to the last insn we copied
- (copy) for new pseudo registers. Do this after the code to jump to
- the end label since that might create a new pseudo too. */
- reg_scan_update (first_copy, copy, max_reg);
-
- /* Mark the exit code as the virtual top of the converted loop. */
- emit_note_before (NOTE_INSN_LOOP_VTOP, exitcode);
-
- delete_insn (next_nonnote_insn (loop_start));
-
- /* Clean up. */
- if (reg_map)
- free (reg_map);
-
- return 1;
-}
-\f
-/* Move all block-beg, block-end, loop-beg, loop-cont, loop-vtop, loop-end,
- eh-beg, eh-end notes between START and END out before START. Assume that
- END is not such a note. START may be such a note. Returns the value
- of the new starting insn, which may be different if the original start
- was such a note. */
-
-rtx
-squeeze_notes (start, end)
- rtx start, end;
-{
- rtx insn;
- rtx next;
-
- for (insn = start; insn != end; insn = next)
- {
- next = NEXT_INSN (insn);
- if (GET_CODE (insn) == NOTE
- && (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END
- || NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG
- || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG
- || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_END
- || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_CONT
- || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_VTOP
- || NOTE_LINE_NUMBER (insn) == NOTE_INSN_EH_REGION_BEG
- || NOTE_LINE_NUMBER (insn) == NOTE_INSN_EH_REGION_END))
- {
- if (insn == start)
- start = next;
- else
- {
- rtx prev = PREV_INSN (insn);
- PREV_INSN (insn) = PREV_INSN (start);
- NEXT_INSN (insn) = start;
- NEXT_INSN (PREV_INSN (insn)) = insn;
- PREV_INSN (NEXT_INSN (insn)) = insn;
- NEXT_INSN (prev) = next;
- PREV_INSN (next) = prev;
- }
- }
- }
-
- return start;
-}
-\f
-/* Compare the instructions before insn E1 with those before E2
- to find an opportunity for cross jumping.
- (This means detecting identical sequences of insns followed by
- jumps to the same place, or followed by a label and a jump
- to that label, and replacing one with a jump to the other.)
-
- Assume E1 is a jump that jumps to label E2
- (that is not always true but it might as well be).
- Find the longest possible equivalent sequences
- and store the first insns of those sequences into *F1 and *F2.
- Store zero there if no equivalent preceding instructions are found.
-
- We give up if we find a label in stream 1.
- Actually we could transfer that label into stream 2. */
-
-static void
-find_cross_jump (e1, e2, minimum, f1, f2)
- rtx e1, e2;
- int minimum;
- rtx *f1, *f2;
-{
- register rtx i1 = e1, i2 = e2;
- register rtx p1, p2;
- int lose = 0;
-
- rtx last1 = 0, last2 = 0;
- rtx afterlast1 = 0, afterlast2 = 0;
-
- *f1 = 0;
- *f2 = 0;
-
- while (1)
- {
- i1 = prev_nonnote_insn (i1);
-
- i2 = PREV_INSN (i2);
- while (i2 && (GET_CODE (i2) == NOTE || GET_CODE (i2) == CODE_LABEL))
- i2 = PREV_INSN (i2);
-
- if (i1 == 0)
- break;
-
- /* Don't allow the range of insns preceding E1 or E2
- to include the other (E2 or E1). */
- if (i2 == e1 || i1 == e2)
- break;
-
- /* If we will get to this code by jumping, those jumps will be
- tensioned to go directly to the new label (before I2),
- so this cross-jumping won't cost extra. So reduce the minimum. */
- if (GET_CODE (i1) == CODE_LABEL)
- {
- --minimum;
- break;
- }
-
- if (i2 == 0 || GET_CODE (i1) != GET_CODE (i2))
- break;
-
- /* Avoid moving insns across EH regions if either of the insns
- can throw. */
- if (flag_exceptions
- && (asynchronous_exceptions || GET_CODE (i1) == CALL_INSN)
- && !in_same_eh_region (i1, i2))
- break;
-
- p1 = PATTERN (i1);
- p2 = PATTERN (i2);
-
- /* If this is a CALL_INSN, compare register usage information.
- If we don't check this on stack register machines, the two
- CALL_INSNs might be merged leaving reg-stack.c with mismatching
- numbers of stack registers in the same basic block.
- If we don't check this on machines with delay slots, a delay slot may
- be filled that clobbers a parameter expected by the subroutine.
-
- ??? We take the simple route for now and assume that if they're
- equal, they were constructed identically. */
-
- if (GET_CODE (i1) == CALL_INSN
- && ! rtx_equal_p (CALL_INSN_FUNCTION_USAGE (i1),
- CALL_INSN_FUNCTION_USAGE (i2)))
- lose = 1;
-
-#ifdef STACK_REGS
- /* If cross_jump_death_matters is not 0, the insn's mode
- indicates whether or not the insn contains any stack-like
- regs. */
-
- if (!lose && cross_jump_death_matters && stack_regs_mentioned (i1))
- {
- /* If register stack conversion has already been done, then
- death notes must also be compared before it is certain that
- the two instruction streams match. */
-
- rtx note;
- HARD_REG_SET i1_regset, i2_regset;
-
- CLEAR_HARD_REG_SET (i1_regset);
- CLEAR_HARD_REG_SET (i2_regset);
-
- for (note = REG_NOTES (i1); note; note = XEXP (note, 1))
- if (REG_NOTE_KIND (note) == REG_DEAD
- && STACK_REG_P (XEXP (note, 0)))
- SET_HARD_REG_BIT (i1_regset, REGNO (XEXP (note, 0)));
-
- for (note = REG_NOTES (i2); note; note = XEXP (note, 1))
- if (REG_NOTE_KIND (note) == REG_DEAD
- && STACK_REG_P (XEXP (note, 0)))
- SET_HARD_REG_BIT (i2_regset, REGNO (XEXP (note, 0)));
-
- GO_IF_HARD_REG_EQUAL (i1_regset, i2_regset, done);
-
- lose = 1;
-
- done:
- ;
- }
-#endif
+ mark_jump_label (PATTERN (copy), copy, 0);
+ emit_barrier_before (loop_start);
+ }
- /* Don't allow old-style asm or volatile extended asms to be accepted
- for cross jumping purposes. It is conceptually correct to allow
- them, since cross-jumping preserves the dynamic instruction order
- even though it is changing the static instruction order. However,
- if an asm is being used to emit an assembler pseudo-op, such as
- the MIPS `.set reorder' pseudo-op, then the static instruction order
- matters and it must be preserved. */
- if (GET_CODE (p1) == ASM_INPUT || GET_CODE (p2) == ASM_INPUT
- || (GET_CODE (p1) == ASM_OPERANDS && MEM_VOLATILE_P (p1))
- || (GET_CODE (p2) == ASM_OPERANDS && MEM_VOLATILE_P (p2)))
- lose = 1;
-
- if (lose || GET_CODE (p1) != GET_CODE (p2)
- || ! rtx_renumbered_equal_p (p1, p2))
- {
- /* The following code helps take care of G++ cleanups. */
- rtx equiv1;
- rtx equiv2;
-
- if (!lose && GET_CODE (p1) == GET_CODE (p2)
- && ((equiv1 = find_reg_note (i1, REG_EQUAL, NULL_RTX)) != 0
- || (equiv1 = find_reg_note (i1, REG_EQUIV, NULL_RTX)) != 0)
- && ((equiv2 = find_reg_note (i2, REG_EQUAL, NULL_RTX)) != 0
- || (equiv2 = find_reg_note (i2, REG_EQUIV, NULL_RTX)) != 0)
- /* If the equivalences are not to a constant, they may
- reference pseudos that no longer exist, so we can't
- use them. */
- && CONSTANT_P (XEXP (equiv1, 0))
- && rtx_equal_p (XEXP (equiv1, 0), XEXP (equiv2, 0)))
- {
- rtx s1 = single_set (i1);
- rtx s2 = single_set (i2);
- if (s1 != 0 && s2 != 0
- && rtx_renumbered_equal_p (SET_DEST (s1), SET_DEST (s2)))
- {
- validate_change (i1, &SET_SRC (s1), XEXP (equiv1, 0), 1);
- validate_change (i2, &SET_SRC (s2), XEXP (equiv2, 0), 1);
- if (! rtx_renumbered_equal_p (p1, p2))
- cancel_changes (0);
- else if (apply_change_group ())
- goto win;
- }
- }
+ emit_label_before (loop_pre_header_label, loop_start);
- /* Insns fail to match; cross jumping is limited to the following
- insns. */
+ /* Now scan from the first insn we copied to the last insn we copied
+ (copy) for new pseudo registers. Do this after the code to jump to
+ the end label since that might create a new pseudo too. */
+ reg_scan_update (first_copy, copy, max_reg);
-#ifdef HAVE_cc0
- /* Don't allow the insn after a compare to be shared by
- cross-jumping unless the compare is also shared.
- Here, if either of these non-matching insns is a compare,
- exclude the following insn from possible cross-jumping. */
- if (sets_cc0_p (p1) || sets_cc0_p (p2))
- last1 = afterlast1, last2 = afterlast2, ++minimum;
-#endif
+ /* Mark the exit code as the virtual top of the converted loop. */
+ emit_note_before (NOTE_INSN_LOOP_VTOP, exitcode);
- /* If cross-jumping here will feed a jump-around-jump
- optimization, this jump won't cost extra, so reduce
- the minimum. */
- if (GET_CODE (i1) == JUMP_INSN
- && JUMP_LABEL (i1)
- && prev_real_insn (JUMP_LABEL (i1)) == e1)
- --minimum;
- break;
- }
+ delete_related_insns (next_nonnote_insn (loop_start));
- win:
- if (GET_CODE (p1) != USE && GET_CODE (p1) != CLOBBER)
- {
- /* Ok, this insn is potentially includable in a cross-jump here. */
- afterlast1 = last1, afterlast2 = last2;
- last1 = i1, last2 = i2, --minimum;
- }
- }
+ /* Clean up. */
+ if (reg_map)
+ free (reg_map);
- if (minimum <= 0 && last1 != 0 && last1 != e1)
- *f1 = last1, *f2 = last2;
+ return 1;
}
-
-static void
-do_cross_jump (insn, newjpos, newlpos)
- rtx insn, newjpos, newlpos;
+\f
+/* Move all block-beg, block-end, loop-beg, loop-cont, loop-vtop, loop-end,
+ notes between START and END out before START. START and END may be such
+ notes. Returns the values of the new starting and ending insns, which
+ may be different if the original ones were such notes.
+ Return true if there were only such notes and no real instructions. */
+
+bool
+squeeze_notes (startp, endp)
+ rtx* startp;
+ rtx* endp;
{
- /* Find an existing label at this point
- or make a new one if there is none. */
- register rtx label = get_label_before (newlpos);
+ rtx start = *startp;
+ rtx end = *endp;
+
+ rtx insn;
+ rtx next;
+ rtx last = NULL;
+ rtx past_end = NEXT_INSN (end);
- /* Make the same jump insn jump to the new point. */
- if (GET_CODE (PATTERN (insn)) == RETURN)
+ for (insn = start; insn != past_end; insn = next)
{
- /* Remove from jump chain of returns. */
- delete_from_jump_chain (insn);
- /* Change the insn. */
- PATTERN (insn) = gen_jump (label);
- INSN_CODE (insn) = -1;
- JUMP_LABEL (insn) = label;
- LABEL_NUSES (label)++;
- /* Add to new the jump chain. */
- if (INSN_UID (label) < max_jump_chain
- && INSN_UID (insn) < max_jump_chain)
+ next = NEXT_INSN (insn);
+ if (GET_CODE (insn) == NOTE
+ && (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END
+ || NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG
+ || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG
+ || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_END
+ || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_CONT
+ || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_VTOP))
{
- jump_chain[INSN_UID (insn)] = jump_chain[INSN_UID (label)];
- jump_chain[INSN_UID (label)] = insn;
+ if (insn == start)
+ start = next;
+ else
+ {
+ rtx prev = PREV_INSN (insn);
+ PREV_INSN (insn) = PREV_INSN (start);
+ NEXT_INSN (insn) = start;
+ NEXT_INSN (PREV_INSN (insn)) = insn;
+ PREV_INSN (NEXT_INSN (insn)) = insn;
+ NEXT_INSN (prev) = next;
+ PREV_INSN (next) = prev;
+ }
}
+ else
+ last = insn;
}
- else
- redirect_jump (insn, label);
- /* Delete the matching insns before the jump. Also, remove any REG_EQUAL
- or REG_EQUIV note in the NEWLPOS stream that isn't also present in
- the NEWJPOS stream. */
+ /* There were no real instructions. */
+ if (start == past_end)
+ return true;
- while (newjpos != insn)
- {
- rtx lnote;
-
- for (lnote = REG_NOTES (newlpos); lnote; lnote = XEXP (lnote, 1))
- if ((REG_NOTE_KIND (lnote) == REG_EQUAL
- || REG_NOTE_KIND (lnote) == REG_EQUIV)
- && ! find_reg_note (newjpos, REG_EQUAL, XEXP (lnote, 0))
- && ! find_reg_note (newjpos, REG_EQUIV, XEXP (lnote, 0)))
- remove_note (newlpos, lnote);
-
- delete_insn (newjpos);
- newjpos = next_real_insn (newjpos);
- newlpos = next_real_insn (newlpos);
- }
+ end = last;
+
+ *startp = start;
+ *endp = end;
+ return false;
}
\f
/* Return the label before INSN, or put a new label there. */
return label;
}
\f
-/* Return 1 if INSN is a jump that jumps to right after TARGET
- only on the condition that TARGET itself would drop through.
- Assumes that TARGET is a conditional jump. */
-
-static int
-jump_back_p (insn, target)
- rtx insn, target;
+/* Given a comparison (CODE ARG0 ARG1), inside an insn, INSN, return a code
+ of reversed comparison if it is possible to do so. Otherwise return UNKNOWN.
+ UNKNOWN may be returned in case we are having CC_MODE compare and we don't
+ know whether it's source is floating point or integer comparison. Machine
+ description should define REVERSIBLE_CC_MODE and REVERSE_CONDITION macros
+ to help this function avoid overhead in these cases. */
+enum rtx_code
+reversed_comparison_code_parts (code, arg0, arg1, insn)
+ rtx insn, arg0, arg1;
+ enum rtx_code code;
{
- rtx cinsn, ctarget;
- enum rtx_code codei, codet;
-
- if (simplejump_p (insn) || ! condjump_p (insn)
- || simplejump_p (target)
- || target != prev_real_insn (JUMP_LABEL (insn)))
- return 0;
+ enum machine_mode mode;
- cinsn = XEXP (SET_SRC (PATTERN (insn)), 0);
- ctarget = XEXP (SET_SRC (PATTERN (target)), 0);
+ /* If this is not actually a comparison, we can't reverse it. */
+ if (GET_RTX_CLASS (code) != '<')
+ return UNKNOWN;
- codei = GET_CODE (cinsn);
- codet = GET_CODE (ctarget);
+ mode = GET_MODE (arg0);
+ if (mode == VOIDmode)
+ mode = GET_MODE (arg1);
- if (XEXP (SET_SRC (PATTERN (insn)), 1) == pc_rtx)
+ /* First see if machine description supply us way to reverse the comparison.
+ Give it priority over everything else to allow machine description to do
+ tricks. */
+#ifdef REVERSIBLE_CC_MODE
+ if (GET_MODE_CLASS (mode) == MODE_CC
+ && REVERSIBLE_CC_MODE (mode))
{
- if (! can_reverse_comparison_p (cinsn, insn))
- return 0;
- codei = reverse_condition (codei);
+#ifdef REVERSE_CONDITION
+ return REVERSE_CONDITION (code, mode);
+#endif
+ return reverse_condition (code);
}
+#endif
- if (XEXP (SET_SRC (PATTERN (target)), 2) == pc_rtx)
+ /* Try a few special cases based on the comparison code. */
+ switch (code)
{
- if (! can_reverse_comparison_p (ctarget, target))
- return 0;
- codet = reverse_condition (codet);
+ case GEU:
+ case GTU:
+ case LEU:
+ case LTU:
+ case NE:
+ case EQ:
+ /* It is always safe to reverse EQ and NE, even for the floating
+ point. Similary the unsigned comparisons are never used for
+ floating point so we can reverse them in the default way. */
+ return reverse_condition (code);
+ case ORDERED:
+ case UNORDERED:
+ case LTGT:
+ case UNEQ:
+ /* In case we already see unordered comparison, we can be sure to
+ be dealing with floating point so we don't need any more tests. */
+ return reverse_condition_maybe_unordered (code);
+ case UNLT:
+ case UNLE:
+ case UNGT:
+ case UNGE:
+ /* We don't have safe way to reverse these yet. */
+ return UNKNOWN;
+ default:
+ break;
}
- return (codei == codet
- && rtx_renumbered_equal_p (XEXP (cinsn, 0), XEXP (ctarget, 0))
- && rtx_renumbered_equal_p (XEXP (cinsn, 1), XEXP (ctarget, 1)));
-}
-\f
-/* Given a comparison, COMPARISON, inside a conditional jump insn, INSN,
- return non-zero if it is safe to reverse this comparison. It is if our
- floating-point is not IEEE, if this is an NE or EQ comparison, or if
- this is known to be an integer comparison. */
-
-int
-can_reverse_comparison_p (comparison, insn)
- rtx comparison;
- rtx insn;
-{
- rtx arg0;
-
- /* If this is not actually a comparison, we can't reverse it. */
- if (GET_RTX_CLASS (GET_CODE (comparison)) != '<')
- return 0;
-
- if (TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT
- /* If this is an NE comparison, it is safe to reverse it to an EQ
- comparison and vice versa, even for floating point. If no operands
- are NaNs, the reversal is valid. If some operand is a NaN, EQ is
- always false and NE is always true, so the reversal is also valid. */
- || flag_fast_math
- || GET_CODE (comparison) == NE
- || GET_CODE (comparison) == EQ)
- return 1;
-
- arg0 = XEXP (comparison, 0);
-
- /* Make sure ARG0 is one of the actual objects being compared. If we
- can't do this, we can't be sure the comparison can be reversed.
-
- Handle cc0 and a MODE_CC register. */
- if ((GET_CODE (arg0) == REG && GET_MODE_CLASS (GET_MODE (arg0)) == MODE_CC)
+ if (GET_MODE_CLASS (mode) == MODE_CC
#ifdef HAVE_cc0
|| arg0 == cc0_rtx
#endif
)
{
- rtx prev = prev_nonnote_insn (insn);
- rtx set;
+ rtx prev;
+ /* Try to search for the comparison to determine the real mode.
+ This code is expensive, but with sane machine description it
+ will be never used, since REVERSIBLE_CC_MODE will return true
+ in all cases. */
+ if (! insn)
+ return UNKNOWN;
- /* First see if the condition code mode alone if enough to say we can
- reverse the condition. If not, then search backwards for a set of
- ARG0. We do not need to check for an insn clobbering it since valid
- code will contain set a set with no intervening clobber. But
- stop when we reach a label. */
-#ifdef REVERSIBLE_CC_MODE
- if (GET_MODE_CLASS (GET_MODE (arg0)) == MODE_CC
- && REVERSIBLE_CC_MODE (GET_MODE (arg0)))
- return 1;
-#endif
-
for (prev = prev_nonnote_insn (insn);
prev != 0 && GET_CODE (prev) != CODE_LABEL;
prev = prev_nonnote_insn (prev))
- if ((set = single_set (prev)) != 0
- && rtx_equal_p (SET_DEST (set), arg0))
- {
- arg0 = SET_SRC (set);
+ {
+ rtx set = set_of (arg0, prev);
+ if (set && GET_CODE (set) == SET
+ && rtx_equal_p (SET_DEST (set), arg0))
+ {
+ rtx src = SET_SRC (set);
- if (GET_CODE (arg0) == COMPARE)
- arg0 = XEXP (arg0, 0);
- break;
- }
+ if (GET_CODE (src) == COMPARE)
+ {
+ rtx comparison = src;
+ arg0 = XEXP (src, 0);
+ mode = GET_MODE (arg0);
+ if (mode == VOIDmode)
+ mode = GET_MODE (XEXP (comparison, 1));
+ break;
+ }
+ /* We can get past reg-reg moves. This may be useful for model
+ of i387 comparisons that first move flag registers around. */
+ if (REG_P (src))
+ {
+ arg0 = src;
+ continue;
+ }
+ }
+ /* If register is clobbered in some ununderstandable way,
+ give up. */
+ if (set)
+ return UNKNOWN;
+ }
}
- /* We can reverse this if ARG0 is a CONST_INT or if its mode is
- not VOIDmode and neither a MODE_CC nor MODE_FLOAT type. */
- return (GET_CODE (arg0) == CONST_INT
- || (GET_MODE (arg0) != VOIDmode
- && GET_MODE_CLASS (GET_MODE (arg0)) != MODE_CC
- && GET_MODE_CLASS (GET_MODE (arg0)) != MODE_FLOAT));
+ /* Test for an integer condition, or a floating-point comparison
+ in which NaNs can be ignored. */
+ if (GET_CODE (arg0) == CONST_INT
+ || (GET_MODE (arg0) != VOIDmode
+ && GET_MODE_CLASS (mode) != MODE_CC
+ && !HONOR_NANS (mode)))
+ return reverse_condition (code);
+
+ return UNKNOWN;
}
+/* An wrapper around the previous function to take COMPARISON as rtx
+ expression. This simplifies many callers. */
+enum rtx_code
+reversed_comparison_code (comparison, insn)
+ rtx comparison, insn;
+{
+ if (GET_RTX_CLASS (GET_CODE (comparison)) != '<')
+ return UNKNOWN;
+ return reversed_comparison_code_parts (GET_CODE (comparison),
+ XEXP (comparison, 0),
+ XEXP (comparison, 1), insn);
+}
+\f
/* Given an rtx-code for a comparison, return the code for the negated
comparison. If no such code exists, return UNKNOWN.
WATCH OUT! reverse_condition is not safe to use on a jump that might
be acting on the results of an IEEE floating point comparison, because
- of the special treatment of non-signaling nans in comparisons.
- Use can_reverse_comparison_p to be sure. */
+ of the special treatment of non-signaling nans in comparisons.
+ Use reversed_comparison_code instead. */
enum rtx_code
reverse_condition (code)
reverse_condition_maybe_unordered (code)
enum rtx_code code;
{
- /* Non-IEEE formats don't have unordered conditions. */
- if (TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT)
- return reverse_condition (code);
-
switch (code)
{
case EQ:
return UNGT;
case LTGT:
return UNEQ;
- case GTU:
- return LEU;
- case GEU:
- return LTU;
- case LTU:
- return GEU;
- case LEU:
- return GTU;
case UNORDERED:
return ORDERED;
case ORDERED:
comparison_dominates_p (code1, code2)
enum rtx_code code1, code2;
{
+ /* UNKNOWN comparison codes can happen as a result of trying to revert
+ comparison codes.
+ They can't match anything, so we have to reject them here. */
+ if (code1 == UNKNOWN || code2 == UNKNOWN)
+ return 0;
+
if (code1 == code2)
return 1;
switch (code1)
{
+ case UNEQ:
+ if (code2 == UNLE || code2 == UNGE)
+ return 1;
+ break;
+
case EQ:
if (code2 == LE || code2 == LEU || code2 == GE || code2 == GEU
|| code2 == ORDERED)
return 1;
break;
+ case UNLT:
+ if (code2 == UNLE || code2 == NE)
+ return 1;
+ break;
+
case LT:
- if (code2 == LE || code2 == NE || code2 == ORDERED)
+ if (code2 == LE || code2 == NE || code2 == ORDERED || code2 == LTGT)
+ return 1;
+ break;
+
+ case UNGT:
+ if (code2 == UNGE || code2 == NE)
return 1;
break;
case GT:
- if (code2 == GE || code2 == NE || code2 == ORDERED)
+ if (code2 == GE || code2 == NE || code2 == ORDERED || code2 == LTGT)
return 1;
break;
break;
case UNORDERED:
- if (code2 == NE)
+ if (code2 == NE || code2 == UNEQ || code2 == UNLE || code2 == UNLT
+ || code2 == UNGE || code2 == UNGT)
return 1;
break;
-
+
default:
break;
}
}
/* Return nonzero if INSN is a (possibly) conditional jump
- and nothing more.
-
+ and nothing more.
+
Use this function is deprecated, since we need to support combined
branch and compare insns. Use any_condjump_p instead whenever possible. */
condjump_p (insn)
rtx insn;
{
- register rtx x = PATTERN (insn);
+ rtx x = PATTERN (insn);
if (GET_CODE (x) != SET
|| GET_CODE (SET_DEST (x)) != PC)
x = SET_SRC (x);
if (GET_CODE (x) == LABEL_REF)
return 1;
- else return (GET_CODE (x) == IF_THEN_ELSE
- && ((GET_CODE (XEXP (x, 2)) == PC
- && (GET_CODE (XEXP (x, 1)) == LABEL_REF
- || GET_CODE (XEXP (x, 1)) == RETURN))
- || (GET_CODE (XEXP (x, 1)) == PC
- && (GET_CODE (XEXP (x, 2)) == LABEL_REF
- || GET_CODE (XEXP (x, 2)) == RETURN))));
+ else
+ return (GET_CODE (x) == IF_THEN_ELSE
+ && ((GET_CODE (XEXP (x, 2)) == PC
+ && (GET_CODE (XEXP (x, 1)) == LABEL_REF
+ || GET_CODE (XEXP (x, 1)) == RETURN))
+ || (GET_CODE (XEXP (x, 1)) == PC
+ && (GET_CODE (XEXP (x, 2)) == LABEL_REF
+ || GET_CODE (XEXP (x, 2)) == RETURN))));
return 0;
}
/* Return nonzero if INSN is a (possibly) conditional jump inside a
PARALLEL.
-
+
Use this function is deprecated, since we need to support combined
branch and compare insns. Use any_condjump_p instead whenever possible. */
condjump_in_parallel_p (insn)
rtx insn;
{
- register rtx x = PATTERN (insn);
+ rtx x = PATTERN (insn);
if (GET_CODE (x) != PARALLEL)
return 0;
/* Return true when insn is a conditional jump. This function works for
instructions containing PC sets in PARALLELs. The instruction may have
various other effects so before removing the jump you must verify
- safe_to_remove_jump_p.
+ onlyjump_p.
Note that unlike condjump_p it returns false for unconditional jumps. */
b = GET_CODE (XEXP (SET_SRC (x), 2));
return ((b == PC && (a == LABEL_REF || a == RETURN))
- || (a == PC && (b == LABEL_REF || b == RETURN)));
+ || (a == PC && (b == LABEL_REF || b == RETURN)));
}
/* Return the label of a conditional jump. */
void *data ATTRIBUTE_UNUSED;
{
rtx x = *loc;
- return x && GET_CODE (x) == RETURN;
+
+ return x && (GET_CODE (x) == RETURN
+ || (GET_CODE (x) == SET && SET_IS_RETURN_P (x)));
}
int
#ifdef HAVE_cc0
+/* Return non-zero if X is an RTX that only sets the condition codes
+ and has no side effects. */
+
+int
+only_sets_cc0_p (x)
+ rtx x;
+{
+
+ if (! x)
+ return 0;
+
+ if (INSN_P (x))
+ x = PATTERN (x);
+
+ return sets_cc0_p (x) == 1 && ! side_effects_p (x);
+}
+
/* Return 1 if X is an RTX that does nothing but set the condition codes
and CLOBBER or USE registers.
Return -1 if X does explicitly set the condition codes,
int
sets_cc0_p (x)
- rtx x ATTRIBUTE_UNUSED;
+ rtx x;
{
+
+ if (! x)
+ return 0;
+
+ if (INSN_P (x))
+ x = PATTERN (x);
+
if (GET_CODE (x) == SET && SET_DEST (x) == cc0_rtx)
return 1;
if (GET_CODE (x) == PARALLEL)
follow_jumps (label)
rtx label;
{
- register rtx insn;
- register rtx next;
- register rtx value = label;
- register int depth;
+ rtx insn;
+ rtx next;
+ rtx value = label;
+ int depth;
for (depth = 0;
(depth < 10
&& (insn = next_active_insn (value)) != 0
&& GET_CODE (insn) == JUMP_INSN
- && ((JUMP_LABEL (insn) != 0 && simplejump_p (insn))
+ && ((JUMP_LABEL (insn) != 0 && any_uncondjump_p (insn)
+ && onlyjump_p (insn))
|| GET_CODE (PATTERN (insn)) == RETURN)
&& (next = NEXT_INSN (insn))
&& GET_CODE (next) == BARRIER);
return value;
}
-/* Assuming that field IDX of X is a vector of label_refs,
- replace each of them by the ultimate label reached by it.
- Return nonzero if a change is made.
- If IGNORE_LOOPS is 0, we do not chain across a NOTE_INSN_LOOP_BEG. */
-
-static int
-tension_vector_labels (x, idx)
- register rtx x;
- register int idx;
-{
- int changed = 0;
- register int i;
- for (i = XVECLEN (x, idx) - 1; i >= 0; i--)
- {
- register rtx olabel = XEXP (XVECEXP (x, idx, i), 0);
- register rtx nlabel = follow_jumps (olabel);
- if (nlabel && nlabel != olabel)
- {
- XEXP (XVECEXP (x, idx, i), 0) = nlabel;
- ++LABEL_NUSES (nlabel);
- if (--LABEL_NUSES (olabel) == 0)
- delete_insn (olabel);
- changed = 1;
- }
- }
- return changed;
-}
\f
/* Find all CODE_LABELs referred to in X, and increment their use counts.
If INSN is a JUMP_INSN and there is at least one CODE_LABEL referenced
must be kept distinct if we have not yet done loop-optimization,
because the gap between them is where loop-optimize
will want to move invariant code to. CROSS_JUMP tells us
- that loop-optimization is done with.
+ that loop-optimization is done with. */
- Once reload has completed (CROSS_JUMP non-zero), we need not consider
- two labels distinct if they are separated by only USE or CLOBBER insns. */
-
-static void
-mark_jump_label (x, insn, cross_jump, in_mem)
- register rtx x;
+void
+mark_jump_label (x, insn, in_mem)
+ rtx x;
rtx insn;
- int cross_jump;
int in_mem;
{
- register RTX_CODE code = GET_CODE (x);
- register int i;
- register const char *fmt;
+ RTX_CODE code = GET_CODE (x);
+ int i;
+ const char *fmt;
switch (code)
{
case SYMBOL_REF:
if (!in_mem)
- return;
+ return;
/* If this is a constant-pool reference, see if it is a label. */
if (CONSTANT_POOL_ADDRESS_P (x))
- mark_jump_label (get_pool_constant (x), insn, cross_jump, in_mem);
+ mark_jump_label (get_pool_constant (x), insn, in_mem);
break;
case LABEL_REF:
{
rtx label = XEXP (x, 0);
- rtx olabel = label;
- rtx note;
- rtx next;
/* Ignore remaining references to unreachable labels that
have been deleted. */
- if (GET_CODE (label) == NOTE
+ if (GET_CODE (label) == NOTE
&& NOTE_LINE_NUMBER (label) == NOTE_INSN_DELETED_LABEL)
break;
if (LABEL_REF_NONLOCAL_P (x))
break;
- /* If there are other labels following this one,
- replace it with the last of the consecutive labels. */
- for (next = NEXT_INSN (label); next; next = NEXT_INSN (next))
- {
- if (GET_CODE (next) == CODE_LABEL)
- label = next;
- else if (cross_jump && GET_CODE (next) == INSN
- && (GET_CODE (PATTERN (next)) == USE
- || GET_CODE (PATTERN (next)) == CLOBBER))
- continue;
- else if (GET_CODE (next) != NOTE)
- break;
- else if (! cross_jump
- && (NOTE_LINE_NUMBER (next) == NOTE_INSN_LOOP_BEG
- || NOTE_LINE_NUMBER (next) == NOTE_INSN_FUNCTION_END
- /* ??? Optional. Disables some optimizations, but
- makes gcov output more accurate with -O. */
- || (flag_test_coverage && NOTE_LINE_NUMBER (next) > 0)))
- break;
- }
-
XEXP (x, 0) = label;
if (! insn || ! INSN_DELETED_P (insn))
++LABEL_NUSES (label);
{
if (GET_CODE (insn) == JUMP_INSN)
JUMP_LABEL (insn) = label;
-
- /* If we've changed OLABEL and we had a REG_LABEL note
- for it, update it as well. */
- else if (label != olabel
- && (note = find_reg_note (insn, REG_LABEL, olabel)) != 0)
- XEXP (note, 0) = label;
-
- /* Otherwise, add a REG_LABEL note for LABEL unless there already
- is one. */
- else if (! find_reg_note (insn, REG_LABEL, label))
+ else
{
- /* This code used to ignore labels which refered to dispatch
- tables to avoid flow.c generating worse code.
-
- However, in the presense of global optimizations like
- gcse which call find_basic_blocks without calling
- life_analysis, not recording such labels will lead
- to compiler aborts because of inconsistencies in the
- flow graph. So we go ahead and record the label.
-
- It may also be the case that the optimization argument
- is no longer valid because of the more accurate cfg
- we build in find_basic_blocks -- it no longer pessimizes
- code when it finds a REG_LABEL note. */
- REG_NOTES (insn) = gen_rtx_INSN_LIST (REG_LABEL, label,
- REG_NOTES (insn));
+ /* Add a REG_LABEL note for LABEL unless there already
+ is one. All uses of a label, except for labels
+ that are the targets of jumps, must have a
+ REG_LABEL note. */
+ if (! find_reg_note (insn, REG_LABEL, label))
+ REG_NOTES (insn) = gen_rtx_INSN_LIST (REG_LABEL, label,
+ REG_NOTES (insn));
}
}
return;
int eltnum = code == ADDR_DIFF_VEC ? 1 : 0;
for (i = 0; i < XVECLEN (x, eltnum); i++)
- mark_jump_label (XVECEXP (x, eltnum, i), NULL_RTX,
- cross_jump, in_mem);
+ mark_jump_label (XVECEXP (x, eltnum, i), NULL_RTX, in_mem);
}
return;
-
+
default:
break;
}
for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
{
if (fmt[i] == 'e')
- mark_jump_label (XEXP (x, i), insn, cross_jump, in_mem);
+ mark_jump_label (XEXP (x, i), insn, in_mem);
else if (fmt[i] == 'E')
{
- register int j;
+ int j;
for (j = 0; j < XVECLEN (x, i); j++)
- mark_jump_label (XVECEXP (x, i, j), insn, cross_jump, in_mem);
+ mark_jump_label (XVECEXP (x, i, j), insn, in_mem);
}
}
}
delete_jump (insn)
rtx insn;
{
- register rtx set = single_set (insn);
+ rtx set = single_set (insn);
if (set && GET_CODE (SET_DEST (set)) == PC)
delete_computation (insn);
/* If we reach a CALL which is not calling a const function
or the callee pops the arguments, then give up. */
if (GET_CODE (our_prev) == CALL_INSN
- && (! CONST_CALL_P (our_prev)
+ && (! CONST_OR_PURE_CALL_P (our_prev)
|| GET_CODE (pat) != SET || GET_CODE (SET_SRC (pat)) != CALL))
break;
{
int dest_regno = REGNO (SET_DEST (pat));
int dest_endregno
- = dest_regno + (dest_regno < FIRST_PSEUDO_REGISTER
+ = (dest_regno
+ + (dest_regno < FIRST_PSEUDO_REGISTER
? HARD_REGNO_NREGS (dest_regno,
- GET_MODE (SET_DEST (pat))) : 1);
+ GET_MODE (SET_DEST (pat))) : 1));
int regno = REGNO (reg);
- int endregno = regno + (regno < FIRST_PSEUDO_REGISTER
- ? HARD_REGNO_NREGS (regno, GET_MODE (reg)) : 1);
+ int endregno
+ = (regno
+ + (regno < FIRST_PSEUDO_REGISTER
+ ? HARD_REGNO_NREGS (regno, GET_MODE (reg)) : 1));
if (dest_regno >= regno
&& dest_endregno <= endregno)
int i;
REG_NOTES (our_prev)
- = gen_rtx_EXPR_LIST (REG_UNUSED, reg, REG_NOTES (our_prev));
+ = gen_rtx_EXPR_LIST (REG_UNUSED, reg,
+ REG_NOTES (our_prev));
for (i = dest_regno; i < dest_endregno; i++)
if (! find_regno_note (our_prev, REG_UNUSED, i))
rtx insn;
{
rtx note, next;
- rtx set;
#ifdef HAVE_cc0
if (reg_referenced_p (cc0_rtx, PATTERN (insn)))
}
#endif
-#ifdef INSN_SCHEDULING
- /* ?!? The schedulers do not keep REG_DEAD notes accurate after
- reload has completed. The schedulers need to be fixed. Until
- they are, we must not rely on the death notes here. */
- if (reload_completed && flag_schedule_insns_after_reload)
- {
- delete_insn (insn);
- return;
- }
-#endif
-
- /* The REG_DEAD note may have been omitted for a register
- which is both set and used by the insn. */
- set = single_set (insn);
- if (set && GET_CODE (SET_DEST (set)) == REG)
- {
- int dest_regno = REGNO (SET_DEST (set));
- int dest_endregno
- = dest_regno + (dest_regno < FIRST_PSEUDO_REGISTER
- ? HARD_REGNO_NREGS (dest_regno,
- GET_MODE (SET_DEST (set))) : 1);
- int i;
-
- for (i = dest_regno; i < dest_endregno; i++)
- {
- if (! refers_to_regno_p (i, i + 1, SET_SRC (set), NULL_PTR)
- || find_regno_note (insn, REG_DEAD, i))
- continue;
-
- note = gen_rtx_EXPR_LIST (REG_DEAD, (i < FIRST_PSEUDO_REGISTER
- ? gen_rtx_REG (reg_raw_mode[i], i)
- : SET_DEST (set)), NULL_RTX);
- delete_prior_computation (note, insn);
- }
- }
-
for (note = REG_NOTES (insn); note; note = next)
{
next = XEXP (note, 1);
delete_prior_computation (note, insn);
}
- delete_insn (insn);
+ delete_related_insns (insn);
}
\f
-/* Delete insn INSN from the chain of insns and update label ref counts.
- May delete some following insns as a consequence; may even delete
- a label elsewhere and insns that follow it.
+/* Delete insn INSN from the chain of insns and update label ref counts
+ and delete insns now unreachable.
+
+ Returns the first insn after INSN that was not deleted.
- Returns the first insn after INSN that was not deleted. */
+ Usage of this instruction is deprecated. Use delete_insn instead and
+ subsequent cfg_cleanup pass to delete unreachable code if needed. */
rtx
-delete_insn (insn)
- register rtx insn;
+delete_related_insns (insn)
+ rtx insn;
{
- register rtx next = NEXT_INSN (insn);
- register rtx prev = PREV_INSN (insn);
- register int was_code_label = (GET_CODE (insn) == CODE_LABEL);
- register int dont_really_delete = 0;
+ int was_code_label = (GET_CODE (insn) == CODE_LABEL);
+ rtx note;
+ rtx next = NEXT_INSN (insn), prev = PREV_INSN (insn);
while (next && INSN_DELETED_P (next))
next = NEXT_INSN (next);
if (INSN_DELETED_P (insn))
return next;
- if (was_code_label)
- remove_node_from_expr_list (insn, &nonlocal_goto_handler_labels);
-
- /* Don't delete user-declared labels. When optimizing, convert them
- to special NOTEs instead. When not optimizing, leave them alone. */
- if (was_code_label && LABEL_NAME (insn) != 0)
- {
- if (! optimize)
- dont_really_delete = 1;
- else if (! dont_really_delete)
- {
- const char *name = LABEL_NAME (insn);
- PUT_CODE (insn, NOTE);
- NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED_LABEL;
- NOTE_SOURCE_FILE (insn) = name;
- dont_really_delete = 1;
- }
- }
- else
- /* Mark this insn as deleted. */
- INSN_DELETED_P (insn) = 1;
-
- /* If this is an unconditional jump, delete it from the jump chain. */
- if (simplejump_p (insn))
- delete_from_jump_chain (insn);
+ delete_insn (insn);
/* If instruction is followed by a barrier,
delete the barrier too. */
if (next != 0 && GET_CODE (next) == BARRIER)
- {
- INSN_DELETED_P (next) = 1;
- next = NEXT_INSN (next);
- }
-
- /* Patch out INSN (and the barrier if any) */
-
- if (! dont_really_delete)
- {
- if (prev)
- {
- NEXT_INSN (prev) = next;
- if (GET_CODE (prev) == INSN && GET_CODE (PATTERN (prev)) == SEQUENCE)
- NEXT_INSN (XVECEXP (PATTERN (prev), 0,
- XVECLEN (PATTERN (prev), 0) - 1)) = next;
- }
-
- if (next)
- {
- PREV_INSN (next) = prev;
- if (GET_CODE (next) == INSN && GET_CODE (PATTERN (next)) == SEQUENCE)
- PREV_INSN (XVECEXP (PATTERN (next), 0, 0)) = prev;
- }
-
- if (prev && NEXT_INSN (prev) == 0)
- set_last_insn (prev);
- }
+ delete_insn (next);
/* If deleting a jump, decrement the count of the label,
and delete the label if it is now unused. */
{
rtx lab = JUMP_LABEL (insn), lab_next;
- if (--LABEL_NUSES (lab) == 0)
+ if (LABEL_NUSES (lab) == 0)
{
/* This can delete NEXT or PREV,
either directly if NEXT is JUMP_LABEL (INSN),
or indirectly through more levels of jumps. */
- delete_insn (lab);
+ delete_related_insns (lab);
/* I feel a little doubtful about this loop,
but I see no clean and sure alternative way
|| GET_CODE (PATTERN (lab_next)) == ADDR_DIFF_VEC))
{
/* If we're deleting the tablejump, delete the dispatch table.
- We may not be able to kill the label immediately preceeding
+ We may not be able to kill the label immediately preceding
just yet, as it might be referenced in code leading up to
the tablejump. */
- delete_insn (lab_next);
+ delete_related_insns (lab_next);
}
}
int len = XVECLEN (pat, diff_vec_p);
for (i = 0; i < len; i++)
- if (--LABEL_NUSES (XEXP (XVECEXP (pat, diff_vec_p, i), 0)) == 0)
- delete_insn (XEXP (XVECEXP (pat, diff_vec_p, i), 0));
+ if (LABEL_NUSES (XEXP (XVECEXP (pat, diff_vec_p, i), 0)) == 0)
+ delete_related_insns (XEXP (XVECEXP (pat, diff_vec_p, i), 0));
while (next && INSN_DELETED_P (next))
next = NEXT_INSN (next);
return next;
}
+ /* Likewise for an ordinary INSN / CALL_INSN with a REG_LABEL note. */
+ if (GET_CODE (insn) == INSN || GET_CODE (insn) == CALL_INSN)
+ for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
+ if (REG_NOTE_KIND (note) == REG_LABEL
+ /* This could also be a NOTE_INSN_DELETED_LABEL note. */
+ && GET_CODE (XEXP (note, 0)) == CODE_LABEL)
+ if (LABEL_NUSES (XEXP (note, 0)) == 0)
+ delete_related_insns (XEXP (note, 0));
+
while (prev && (INSN_DELETED_P (prev) || GET_CODE (prev) == NOTE))
prev = PREV_INSN (prev);
&& GET_CODE (NEXT_INSN (insn)) == JUMP_INSN
&& (GET_CODE (PATTERN (NEXT_INSN (insn))) == ADDR_VEC
|| GET_CODE (PATTERN (NEXT_INSN (insn))) == ADDR_DIFF_VEC))
- next = delete_insn (NEXT_INSN (insn));
+ next = delete_related_insns (NEXT_INSN (insn));
/* If INSN was a label, delete insns following it if now unreachable. */
if (was_code_label && prev && GET_CODE (prev) == BARRIER)
{
- register RTX_CODE code;
+ RTX_CODE code;
while (next != 0
&& (GET_RTX_CLASS (code = GET_CODE (next)) == 'i'
|| code == NOTE || code == BARRIER
deletion of unreachable code, after a different label.
As long as the value from this recursive call is correct,
this invocation functions correctly. */
- next = delete_insn (next);
+ next = delete_related_insns (next);
}
}
void
delete_for_peephole (from, to)
- register rtx from, to;
+ rtx from, to;
{
- register rtx insn = from;
+ rtx insn = from;
while (1)
{
- register rtx next = NEXT_INSN (insn);
- register rtx prev = PREV_INSN (insn);
+ rtx next = NEXT_INSN (insn);
+ rtx prev = PREV_INSN (insn);
if (GET_CODE (insn) != NOTE)
{
so it's possible to get spurious warnings from this. */
void
-never_reached_warning (avoided_insn)
- rtx avoided_insn;
+never_reached_warning (avoided_insn, finish)
+ rtx avoided_insn, finish;
{
rtx insn;
rtx a_line_note = NULL;
- int two_avoided_lines = 0;
- int contains_insn = 0;
-
+ int two_avoided_lines = 0, contains_insn = 0, reached_end = 0;
+
if (! warn_notreached)
return;
/* Scan forwards, looking at LINE_NUMBER notes, until
we hit a LABEL or we run out of insns. */
-
+
for (insn = avoided_insn; insn != NULL; insn = NEXT_INSN (insn))
{
- if (GET_CODE (insn) == CODE_LABEL)
- break;
- else if (GET_CODE (insn) == NOTE /* A line number note? */
- && NOTE_LINE_NUMBER (insn) >= 0)
+ if (finish == NULL && GET_CODE (insn) == CODE_LABEL)
+ break;
+
+ if (GET_CODE (insn) == NOTE /* A line number note? */
+ && NOTE_LINE_NUMBER (insn) >= 0)
{
if (a_line_note == NULL)
a_line_note = insn;
two_avoided_lines |= (NOTE_LINE_NUMBER (a_line_note)
!= NOTE_LINE_NUMBER (insn));
}
- else if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
- contains_insn = 1;
+ else if (INSN_P (insn))
+ {
+ if (reached_end)
+ break;
+ contains_insn = 1;
+ }
+
+ if (insn == finish)
+ reached_end = 1;
}
if (two_avoided_lines && contains_insn)
warning_with_file_and_line (NOTE_SOURCE_FILE (a_line_note),
rtx olabel, nlabel;
rtx insn;
{
- register rtx x = *loc;
- register RTX_CODE code = GET_CODE (x);
- register int i;
- register const char *fmt;
+ rtx x = *loc;
+ RTX_CODE code = GET_CODE (x);
+ int i;
+ const char *fmt;
if (code == LABEL_REF)
{
if (nlabel)
n = gen_rtx_LABEL_REF (VOIDmode, nlabel);
else
- n = gen_rtx_RETURN (VOIDmode);
+ n = gen_rtx_RETURN (VOIDmode);
validate_change (insn, loc, n, 1);
return;
redirect_exp_1 (&XEXP (x, i), olabel, nlabel, insn);
else if (fmt[i] == 'E')
{
- register int j;
+ int j;
for (j = 0; j < XVECLEN (x, i); j++)
redirect_exp_1 (&XVECEXP (x, i, j), olabel, nlabel, insn);
}
/* Similar, but apply the change group and report success or failure. */
-int
-redirect_exp (loc, olabel, nlabel, insn)
- rtx *loc;
+static int
+redirect_exp (olabel, nlabel, insn)
rtx olabel, nlabel;
rtx insn;
{
+ rtx *loc;
+
+ if (GET_CODE (PATTERN (insn)) == PARALLEL)
+ loc = &XVECEXP (PATTERN (insn), 0, 0);
+ else
+ loc = &PATTERN (insn);
+
redirect_exp_1 (loc, olabel, nlabel, insn);
if (num_validated_changes () == 0)
return 0;
rtx jump, nlabel;
{
int ochanges = num_validated_changes ();
- redirect_exp_1 (&PATTERN (jump), JUMP_LABEL (jump), nlabel, jump);
+ rtx *loc;
+
+ if (GET_CODE (PATTERN (jump)) == PARALLEL)
+ loc = &XVECEXP (PATTERN (jump), 0, 0);
+ else
+ loc = &PATTERN (jump);
+
+ redirect_exp_1 (loc, JUMP_LABEL (jump), nlabel, jump);
return num_validated_changes () > ochanges;
}
(this can only occur for NLABEL == 0). */
int
-redirect_jump (jump, nlabel)
+redirect_jump (jump, nlabel, delete_unused)
rtx jump, nlabel;
+ int delete_unused;
{
- register rtx olabel = JUMP_LABEL (jump);
+ rtx olabel = JUMP_LABEL (jump);
if (nlabel == olabel)
return 1;
- if (! redirect_exp (&PATTERN (jump), olabel, nlabel, jump))
- return 0;
-
- /* If this is an unconditional branch, delete it from the jump_chain of
- OLABEL and add it to the jump_chain of NLABEL (assuming both labels
- have UID's in range and JUMP_CHAIN is valid). */
- if (jump_chain && (simplejump_p (jump)
- || GET_CODE (PATTERN (jump)) == RETURN))
- {
- int label_index = nlabel ? INSN_UID (nlabel) : 0;
-
- delete_from_jump_chain (jump);
- if (label_index < max_jump_chain
- && INSN_UID (jump) < max_jump_chain)
- {
- jump_chain[INSN_UID (jump)] = jump_chain[label_index];
- jump_chain[label_index] = jump;
- }
- }
+ if (! redirect_exp (olabel, nlabel, jump))
+ return 0;
JUMP_LABEL (jump) = nlabel;
if (nlabel)
/* If we're eliding the jump over exception cleanups at the end of a
function, move the function end note so that -Wreturn-type works. */
- if (olabel && NEXT_INSN (olabel)
+ if (olabel && nlabel
+ && NEXT_INSN (olabel)
&& GET_CODE (NEXT_INSN (olabel)) == NOTE
&& NOTE_LINE_NUMBER (NEXT_INSN (olabel)) == NOTE_INSN_FUNCTION_END)
emit_note_after (NOTE_INSN_FUNCTION_END, nlabel);
- if (olabel && --LABEL_NUSES (olabel) == 0)
- delete_insn (olabel);
+ if (olabel && --LABEL_NUSES (olabel) == 0 && delete_unused
+ /* Undefined labels will remain outside the insn stream. */
+ && INSN_UID (olabel))
+ delete_related_insns (olabel);
return 1;
}
-/* Invert the jump condition of rtx X contained in jump insn, INSN.
+/* Invert the jump condition of rtx X contained in jump insn, INSN.
Accrue the modifications into the change group. */
static void
-invert_exp_1 (x, insn)
- rtx x;
+invert_exp_1 (insn)
rtx insn;
{
- register RTX_CODE code;
- register int i;
- register const char *fmt;
+ RTX_CODE code;
+ rtx x = pc_set (insn);
+
+ if (!x)
+ abort ();
+ x = SET_SRC (x);
code = GET_CODE (x);
if (code == IF_THEN_ELSE)
{
- register rtx comp = XEXP (x, 0);
- register rtx tem;
+ rtx comp = XEXP (x, 0);
+ rtx tem;
+ enum rtx_code reversed_code;
/* We can do this in two ways: The preferable way, which can only
be done if this is not an integer comparison, is to reverse
the comparison code. Otherwise, swap the THEN-part and ELSE-part
of the IF_THEN_ELSE. If we can't do either, fail. */
- if (can_reverse_comparison_p (comp, insn))
+ reversed_code = reversed_comparison_code (comp, insn);
+
+ if (reversed_code != UNKNOWN)
{
validate_change (insn, &XEXP (x, 0),
- gen_rtx_fmt_ee (reverse_condition (GET_CODE (comp)),
+ gen_rtx_fmt_ee (reversed_code,
GET_MODE (comp), XEXP (comp, 0),
XEXP (comp, 1)),
1);
return;
}
-
+
tem = XEXP (x, 1);
validate_change (insn, &XEXP (x, 1), XEXP (x, 2), 1);
validate_change (insn, &XEXP (x, 2), tem, 1);
- return;
- }
-
- fmt = GET_RTX_FORMAT (code);
- for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
- {
- if (fmt[i] == 'e')
- invert_exp_1 (XEXP (x, i), insn);
- else if (fmt[i] == 'E')
- {
- register int j;
- for (j = 0; j < XVECLEN (x, i); j++)
- invert_exp_1 (XVECEXP (x, i, j), insn);
- }
}
+ else
+ abort ();
}
-/* Invert the jump condition of rtx X contained in jump insn, INSN.
+/* Invert the jump condition of conditional jump insn, INSN.
Return 1 if we can do so, 0 if we cannot find a way to do so that
matches a pattern. */
-int
-invert_exp (x, insn)
- rtx x;
+static int
+invert_exp (insn)
rtx insn;
{
- invert_exp_1 (x, insn);
+ invert_exp_1 (insn);
if (num_validated_changes () == 0)
return 0;
int ochanges;
ochanges = num_validated_changes ();
- invert_exp_1 (PATTERN (jump), jump);
+ invert_exp_1 (jump);
if (num_validated_changes () == ochanges)
return 0;
NLABEL instead of where it jumps now. Return true if successful. */
int
-invert_jump (jump, nlabel)
+invert_jump (jump, nlabel, delete_unused)
rtx jump, nlabel;
+ int delete_unused;
{
/* We have to either invert the condition and change the label or
do neither. Either operation could fail. We first try to invert
the jump. If that succeeds, we try changing the label. If that fails,
we invert the jump back to what it was. */
- if (! invert_exp (PATTERN (jump), jump))
+ if (! invert_exp (jump))
return 0;
- if (redirect_jump (jump, nlabel))
+ if (redirect_jump (jump, nlabel, delete_unused))
{
- /* An inverted jump means that a probability taken becomes a
- probability not taken. Subtract the branch probability from the
- probability base to convert it back to a taken probability. */
-
- rtx note = find_reg_note (jump, REG_BR_PROB, NULL_RTX);
- if (note)
- XEXP (note, 0) = GEN_INT (REG_BR_PROB_BASE - INTVAL (XEXP (note, 0)));
+ invert_br_probabilities (jump);
return 1;
}
- if (! invert_exp (PATTERN (jump), jump))
+ if (! invert_exp (jump))
/* This should just be putting it back the way it was. */
abort ();
return 0;
}
-/* Delete the instruction JUMP from any jump chain it might be on. */
-
-static void
-delete_from_jump_chain (jump)
- rtx jump;
-{
- int index;
- rtx olabel = JUMP_LABEL (jump);
-
- /* Handle unconditional jumps. */
- if (jump_chain && olabel != 0
- && INSN_UID (olabel) < max_jump_chain
- && simplejump_p (jump))
- index = INSN_UID (olabel);
- /* Handle return insns. */
- else if (jump_chain && GET_CODE (PATTERN (jump)) == RETURN)
- index = 0;
- else return;
-
- if (jump_chain[index] == jump)
- jump_chain[index] = jump_chain[INSN_UID (jump)];
- else
- {
- rtx insn;
-
- for (insn = jump_chain[index];
- insn != 0;
- insn = jump_chain[INSN_UID (insn)])
- if (jump_chain[INSN_UID (insn)] == jump)
- {
- jump_chain[INSN_UID (insn)] = jump_chain[INSN_UID (jump)];
- break;
- }
- }
-}
-\f
-/* Make jump JUMP jump to label NLABEL, assuming it used to be a tablejump.
-
- If the old jump target label (before the dispatch table) becomes unused,
- it and the dispatch table may be deleted. In that case, find the insn
- before the jump references that label and delete it and logical successors
- too. */
-
-static void
-redirect_tablejump (jump, nlabel)
- rtx jump, nlabel;
-{
- register rtx olabel = JUMP_LABEL (jump);
-
- /* Add this jump to the jump_chain of NLABEL. */
- if (jump_chain && INSN_UID (nlabel) < max_jump_chain
- && INSN_UID (jump) < max_jump_chain)
- {
- jump_chain[INSN_UID (jump)] = jump_chain[INSN_UID (nlabel)];
- jump_chain[INSN_UID (nlabel)] = jump;
- }
-
- PATTERN (jump) = gen_jump (nlabel);
- JUMP_LABEL (jump) = nlabel;
- ++LABEL_NUSES (nlabel);
- INSN_CODE (jump) = -1;
-
- if (--LABEL_NUSES (olabel) == 0)
- {
- delete_labelref_insn (jump, olabel, 0);
- delete_insn (olabel);
- }
-}
-
-/* Find the insn referencing LABEL that is a logical predecessor of INSN.
- If we found one, delete it and then delete this insn if DELETE_THIS is
- non-zero. Return non-zero if INSN or a predecessor references LABEL. */
-
-static int
-delete_labelref_insn (insn, label, delete_this)
- rtx insn, label;
- int delete_this;
-{
- int deleted = 0;
- rtx link;
-
- if (GET_CODE (insn) != NOTE
- && reg_mentioned_p (label, PATTERN (insn)))
- {
- if (delete_this)
- {
- delete_insn (insn);
- deleted = 1;
- }
- else
- return 1;
- }
-
- for (link = LOG_LINKS (insn); link; link = XEXP (link, 1))
- if (delete_labelref_insn (XEXP (link, 0), label, 1))
- {
- if (delete_this)
- {
- delete_insn (insn);
- deleted = 1;
- }
- else
- return 1;
- }
-
- return deleted;
-}
\f
/* Like rtx_equal_p except that it considers two REGs as equal
if they renumber to the same value and considers two commutative
rtx_renumbered_equal_p (x, y)
rtx x, y;
{
- register int i;
- register RTX_CODE code = GET_CODE (x);
- register const char *fmt;
-
+ int i;
+ RTX_CODE code = GET_CODE (x);
+ const char *fmt;
+
if (x == y)
return 1;
&& GET_CODE (SUBREG_REG (y)) == REG)))
{
int reg_x = -1, reg_y = -1;
- int word_x = 0, word_y = 0;
+ int byte_x = 0, byte_y = 0;
if (GET_MODE (x) != GET_MODE (y))
return 0;
if (code == SUBREG)
{
reg_x = REGNO (SUBREG_REG (x));
- word_x = SUBREG_WORD (x);
+ byte_x = SUBREG_BYTE (x);
if (reg_renumber[reg_x] >= 0)
{
- reg_x = reg_renumber[reg_x] + word_x;
- word_x = 0;
+ reg_x = subreg_regno_offset (reg_renumber[reg_x],
+ GET_MODE (SUBREG_REG (x)),
+ byte_x,
+ GET_MODE (x));
+ byte_x = 0;
}
}
-
else
{
reg_x = REGNO (x);
if (GET_CODE (y) == SUBREG)
{
reg_y = REGNO (SUBREG_REG (y));
- word_y = SUBREG_WORD (y);
+ byte_y = SUBREG_BYTE (y);
if (reg_renumber[reg_y] >= 0)
{
- reg_y = reg_renumber[reg_y];
- word_y = 0;
+ reg_y = subreg_regno_offset (reg_renumber[reg_y],
+ GET_MODE (SUBREG_REG (y)),
+ byte_y,
+ GET_MODE (y));
+ byte_y = 0;
}
}
-
else
{
reg_y = REGNO (y);
reg_y = reg_renumber[reg_y];
}
- return reg_x >= 0 && reg_x == reg_y && word_x == word_y;
+ return reg_x >= 0 && reg_x == reg_y && byte_x == byte_y;
}
- /* Now we have disposed of all the cases
+ /* Now we have disposed of all the cases
in which different rtx codes can match. */
if (code != GET_CODE (y))
return 0;
fmt = GET_RTX_FORMAT (code);
for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
{
- register int j;
+ int j;
switch (fmt[i])
{
case 'w':
return 0;
break;
+ case 't':
+ if (XTREE (x, i) != XTREE (y, i))
+ return 0;
+ break;
+
case 's':
if (strcmp (XSTR (x, i), XSTR (y, i)))
return 0;
{
int base = true_regnum (SUBREG_REG (x));
if (base >= 0 && base < FIRST_PSEUDO_REGISTER)
- return SUBREG_WORD (x) + base;
+ return base + subreg_regno_offset (REGNO (SUBREG_REG (x)),
+ GET_MODE (SUBREG_REG (x)),
+ SUBREG_BYTE (x), GET_MODE (x));
}
return -1;
}
-\f
-/* Optimize code of the form:
-
- for (x = a[i]; x; ...)
- ...
- for (x = a[i]; x; ...)
- ...
- foo:
-
- Loop optimize will change the above code into
-
- if (x = a[i])
- for (;;)
- { ...; if (! (x = ...)) break; }
- if (x = a[i])
- for (;;)
- { ...; if (! (x = ...)) break; }
- foo:
-
- In general, if the first test fails, the program can branch
- directly to `foo' and skip the second try which is doomed to fail.
- We run this after loop optimization and before flow analysis. */
-
-/* When comparing the insn patterns, we track the fact that different
- pseudo-register numbers may have been used in each computation.
- The following array stores an equivalence -- same_regs[I] == J means
- that pseudo register I was used in the first set of tests in a context
- where J was used in the second set. We also count the number of such
- pending equivalences. If nonzero, the expressions really aren't the
- same. */
-
-static int *same_regs;
-
-static int num_same_regs;
-
-/* Track any registers modified between the target of the first jump and
- the second jump. They never compare equal. */
-
-static char *modified_regs;
-
-/* Record if memory was modified. */
-
-static int modified_mem;
-
-/* Called via note_stores on each insn between the target of the first
- branch and the second branch. It marks any changed registers. */
-
-static void
-mark_modified_reg (dest, x, data)
- rtx dest;
- rtx x ATTRIBUTE_UNUSED;
- void *data ATTRIBUTE_UNUSED;
-{
- int regno;
- unsigned int i;
-
- if (GET_CODE (dest) == SUBREG)
- dest = SUBREG_REG (dest);
-
- if (GET_CODE (dest) == MEM)
- modified_mem = 1;
-
- if (GET_CODE (dest) != REG)
- return;
-
- regno = REGNO (dest);
- if (regno >= FIRST_PSEUDO_REGISTER)
- modified_regs[regno] = 1;
- else
- for (i = 0; i < HARD_REGNO_NREGS (regno, GET_MODE (dest)); i++)
- modified_regs[regno + i] = 1;
-}
-
-/* F is the first insn in the chain of insns. */
-
-void
-thread_jumps (f, max_reg, flag_before_loop)
- rtx f;
- int max_reg;
- int flag_before_loop;
-{
- /* Basic algorithm is to find a conditional branch,
- the label it may branch to, and the branch after
- that label. If the two branches test the same condition,
- walk back from both branch paths until the insn patterns
- differ, or code labels are hit. If we make it back to
- the target of the first branch, then we know that the first branch
- will either always succeed or always fail depending on the relative
- senses of the two branches. So adjust the first branch accordingly
- in this case. */
-
- rtx label, b1, b2, t1, t2;
- enum rtx_code code1, code2;
- rtx b1op0, b1op1, b2op0, b2op1;
- int changed = 1;
- int i;
- int *all_reset;
-
- /* Allocate register tables and quick-reset table. */
- modified_regs = (char *) xmalloc (max_reg * sizeof (char));
- same_regs = (int *) xmalloc (max_reg * sizeof (int));
- all_reset = (int *) xmalloc (max_reg * sizeof (int));
- for (i = 0; i < max_reg; i++)
- all_reset[i] = -1;
-
- while (changed)
- {
- changed = 0;
-
- for (b1 = f; b1; b1 = NEXT_INSN (b1))
- {
- /* Get to a candidate branch insn. */
- if (GET_CODE (b1) != JUMP_INSN
- || ! condjump_p (b1) || simplejump_p (b1)
- || JUMP_LABEL (b1) == 0)
- continue;
-
- bzero (modified_regs, max_reg * sizeof (char));
- modified_mem = 0;
-
- bcopy ((char *) all_reset, (char *) same_regs,
- max_reg * sizeof (int));
- num_same_regs = 0;
-
- label = JUMP_LABEL (b1);
-
- /* Look for a branch after the target. Record any registers and
- memory modified between the target and the branch. Stop when we
- get to a label since we can't know what was changed there. */
- for (b2 = NEXT_INSN (label); b2; b2 = NEXT_INSN (b2))
- {
- if (GET_CODE (b2) == CODE_LABEL)
- break;
-
- else if (GET_CODE (b2) == JUMP_INSN)
- {
- /* If this is an unconditional jump and is the only use of
- its target label, we can follow it. */
- if (simplejump_p (b2)
- && JUMP_LABEL (b2) != 0
- && LABEL_NUSES (JUMP_LABEL (b2)) == 1)
- {
- b2 = JUMP_LABEL (b2);
- continue;
- }
- else
- break;
- }
-
- if (GET_CODE (b2) != CALL_INSN && GET_CODE (b2) != INSN)
- continue;
-
- if (GET_CODE (b2) == CALL_INSN)
- {
- modified_mem = 1;
- for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- if (call_used_regs[i] && ! fixed_regs[i]
- && i != STACK_POINTER_REGNUM
- && i != FRAME_POINTER_REGNUM
- && i != HARD_FRAME_POINTER_REGNUM
- && i != ARG_POINTER_REGNUM)
- modified_regs[i] = 1;
- }
-
- note_stores (PATTERN (b2), mark_modified_reg, NULL);
- }
-
- /* Check the next candidate branch insn from the label
- of the first. */
- if (b2 == 0
- || GET_CODE (b2) != JUMP_INSN
- || b2 == b1
- || ! condjump_p (b2)
- || simplejump_p (b2))
- continue;
-
- /* Get the comparison codes and operands, reversing the
- codes if appropriate. If we don't have comparison codes,
- we can't do anything. */
- b1op0 = XEXP (XEXP (SET_SRC (PATTERN (b1)), 0), 0);
- b1op1 = XEXP (XEXP (SET_SRC (PATTERN (b1)), 0), 1);
- code1 = GET_CODE (XEXP (SET_SRC (PATTERN (b1)), 0));
- if (XEXP (SET_SRC (PATTERN (b1)), 1) == pc_rtx)
- code1 = reverse_condition (code1);
-
- b2op0 = XEXP (XEXP (SET_SRC (PATTERN (b2)), 0), 0);
- b2op1 = XEXP (XEXP (SET_SRC (PATTERN (b2)), 0), 1);
- code2 = GET_CODE (XEXP (SET_SRC (PATTERN (b2)), 0));
- if (XEXP (SET_SRC (PATTERN (b2)), 1) == pc_rtx)
- code2 = reverse_condition (code2);
-
- /* If they test the same things and knowing that B1 branches
- tells us whether or not B2 branches, check if we
- can thread the branch. */
- if (rtx_equal_for_thread_p (b1op0, b2op0, b2)
- && rtx_equal_for_thread_p (b1op1, b2op1, b2)
- && (comparison_dominates_p (code1, code2)
- || (can_reverse_comparison_p (XEXP (SET_SRC (PATTERN (b1)),
- 0),
- b1)
- && comparison_dominates_p (code1, reverse_condition (code2)))))
-
- {
- t1 = prev_nonnote_insn (b1);
- t2 = prev_nonnote_insn (b2);
-
- while (t1 != 0 && t2 != 0)
- {
- if (t2 == label)
- {
- /* We have reached the target of the first branch.
- If there are no pending register equivalents,
- we know that this branch will either always
- succeed (if the senses of the two branches are
- the same) or always fail (if not). */
- rtx new_label;
-
- if (num_same_regs != 0)
- break;
-
- if (comparison_dominates_p (code1, code2))
- new_label = JUMP_LABEL (b2);
- else
- new_label = get_label_after (b2);
-
- if (JUMP_LABEL (b1) != new_label)
- {
- rtx prev = PREV_INSN (new_label);
-
- if (flag_before_loop
- && GET_CODE (prev) == NOTE
- && NOTE_LINE_NUMBER (prev) == NOTE_INSN_LOOP_BEG)
- {
- /* Don't thread to the loop label. If a loop
- label is reused, loop optimization will
- be disabled for that loop. */
- new_label = gen_label_rtx ();
- emit_label_after (new_label, PREV_INSN (prev));
- }
- changed |= redirect_jump (b1, new_label);
- }
- break;
- }
-
- /* If either of these is not a normal insn (it might be
- a JUMP_INSN, CALL_INSN, or CODE_LABEL) we fail. (NOTEs
- have already been skipped above.) Similarly, fail
- if the insns are different. */
- if (GET_CODE (t1) != INSN || GET_CODE (t2) != INSN
- || recog_memoized (t1) != recog_memoized (t2)
- || ! rtx_equal_for_thread_p (PATTERN (t1),
- PATTERN (t2), t2))
- break;
-
- t1 = prev_nonnote_insn (t1);
- t2 = prev_nonnote_insn (t2);
- }
- }
- }
- }
-
- /* Clean up. */
- free (modified_regs);
- free (same_regs);
- free (all_reset);
-}
-\f
-/* This is like RTX_EQUAL_P except that it knows about our handling of
- possibly equivalent registers and knows to consider volatile and
- modified objects as not equal.
-
- YINSN is the insn containing Y. */
-
-int
-rtx_equal_for_thread_p (x, y, yinsn)
- rtx x, y;
- rtx yinsn;
-{
- register int i;
- register int j;
- register enum rtx_code code;
- register const char *fmt;
-
- code = GET_CODE (x);
- /* Rtx's of different codes cannot be equal. */
- if (code != GET_CODE (y))
- return 0;
-
- /* (MULT:SI x y) and (MULT:HI x y) are NOT equivalent.
- (REG:SI x) and (REG:HI x) are NOT equivalent. */
-
- if (GET_MODE (x) != GET_MODE (y))
- return 0;
-
- /* For floating-point, consider everything unequal. This is a bit
- pessimistic, but this pass would only rarely do anything for FP
- anyway. */
- if (TARGET_FLOAT_FORMAT == IEEE_FLOAT_FORMAT
- && FLOAT_MODE_P (GET_MODE (x)) && ! flag_fast_math)
- return 0;
-
- /* For commutative operations, the RTX match if the operand match in any
- order. Also handle the simple binary and unary cases without a loop. */
- if (code == EQ || code == NE || GET_RTX_CLASS (code) == 'c')
- return ((rtx_equal_for_thread_p (XEXP (x, 0), XEXP (y, 0), yinsn)
- && rtx_equal_for_thread_p (XEXP (x, 1), XEXP (y, 1), yinsn))
- || (rtx_equal_for_thread_p (XEXP (x, 0), XEXP (y, 1), yinsn)
- && rtx_equal_for_thread_p (XEXP (x, 1), XEXP (y, 0), yinsn)));
- else if (GET_RTX_CLASS (code) == '<' || GET_RTX_CLASS (code) == '2')
- return (rtx_equal_for_thread_p (XEXP (x, 0), XEXP (y, 0), yinsn)
- && rtx_equal_for_thread_p (XEXP (x, 1), XEXP (y, 1), yinsn));
- else if (GET_RTX_CLASS (code) == '1')
- return rtx_equal_for_thread_p (XEXP (x, 0), XEXP (y, 0), yinsn);
-
- /* Handle special-cases first. */
- switch (code)
- {
- case REG:
- if (REGNO (x) == REGNO (y) && ! modified_regs[REGNO (x)])
- return 1;
-
- /* If neither is user variable or hard register, check for possible
- equivalence. */
- if (REG_USERVAR_P (x) || REG_USERVAR_P (y)
- || REGNO (x) < FIRST_PSEUDO_REGISTER
- || REGNO (y) < FIRST_PSEUDO_REGISTER)
- return 0;
-
- if (same_regs[REGNO (x)] == -1)
- {
- same_regs[REGNO (x)] = REGNO (y);
- num_same_regs++;
-
- /* If this is the first time we are seeing a register on the `Y'
- side, see if it is the last use. If not, we can't thread the
- jump, so mark it as not equivalent. */
- if (REGNO_LAST_UID (REGNO (y)) != INSN_UID (yinsn))
- return 0;
-
- return 1;
- }
- else
- return (same_regs[REGNO (x)] == (int) REGNO (y));
-
- break;
-
- case MEM:
- /* If memory modified or either volatile, not equivalent.
- Else, check address. */
- if (modified_mem || MEM_VOLATILE_P (x) || MEM_VOLATILE_P (y))
- return 0;
-
- return rtx_equal_for_thread_p (XEXP (x, 0), XEXP (y, 0), yinsn);
-
- case ASM_INPUT:
- if (MEM_VOLATILE_P (x) || MEM_VOLATILE_P (y))
- return 0;
-
- break;
-
- case SET:
- /* Cancel a pending `same_regs' if setting equivalenced registers.
- Then process source. */
- if (GET_CODE (SET_DEST (x)) == REG
- && GET_CODE (SET_DEST (y)) == REG)
- {
- if (same_regs[REGNO (SET_DEST (x))] == (int) REGNO (SET_DEST (y)))
- {
- same_regs[REGNO (SET_DEST (x))] = -1;
- num_same_regs--;
- }
- else if (REGNO (SET_DEST (x)) != REGNO (SET_DEST (y)))
- return 0;
- }
- else
- if (rtx_equal_for_thread_p (SET_DEST (x), SET_DEST (y), yinsn) == 0)
- return 0;
-
- return rtx_equal_for_thread_p (SET_SRC (x), SET_SRC (y), yinsn);
-
- case LABEL_REF:
- return XEXP (x, 0) == XEXP (y, 0);
-
- case SYMBOL_REF:
- return XSTR (x, 0) == XSTR (y, 0);
-
- default:
- break;
- }
-
- if (x == y)
- return 1;
-
- fmt = GET_RTX_FORMAT (code);
- for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
- {
- switch (fmt[i])
- {
- case 'w':
- if (XWINT (x, i) != XWINT (y, i))
- return 0;
- break;
-
- case 'n':
- case 'i':
- if (XINT (x, i) != XINT (y, i))
- return 0;
- break;
-
- case 'V':
- case 'E':
- /* Two vectors must have the same length. */
- if (XVECLEN (x, i) != XVECLEN (y, i))
- return 0;
-
- /* And the corresponding elements must match. */
- for (j = 0; j < XVECLEN (x, i); j++)
- if (rtx_equal_for_thread_p (XVECEXP (x, i, j),
- XVECEXP (y, i, j), yinsn) == 0)
- return 0;
- break;
-
- case 'e':
- if (rtx_equal_for_thread_p (XEXP (x, i), XEXP (y, i), yinsn) == 0)
- return 0;
- break;
-
- case 'S':
- case 's':
- if (strcmp (XSTR (x, i), XSTR (y, i)))
- return 0;
- break;
-
- case 'u':
- /* These are just backpointers, so they don't matter. */
- break;
-
- case '0':
- case 't':
- break;
-
- /* It is believed that rtx's at this level will never
- contain anything but integers and other rtx's,
- except for within LABEL_REFs and SYMBOL_REFs. */
- default:
- abort ();
- }
- }
- return 1;
-}
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