/* Optimize jump instructions, for GNU compiler.
Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997
- 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
+ 1998, 1999, 2000, 2001, 2002, 2003, 2004 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
+ The subroutines redirect_jump and invert_jump are used
from other passes as well. */
#include "config.h"
#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
#include "rtl.h"
#include "tm_p.h"
#include "flags.h"
#include "expr.h"
#include "real.h"
#include "except.h"
+#include "diagnostic.h"
#include "toplev.h"
#include "reload.h"
+#include "predict.h"
+#include "timevar.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;
-
-/* 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 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 delete_computation PARAMS ((rtx));
-static void redirect_exp_1 PARAMS ((rtx *, rtx, rtx, rtx));
-static int redirect_exp PARAMS ((rtx, rtx, rtx));
-static void invert_exp_1 PARAMS ((rtx));
-static int invert_exp PARAMS ((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 returnjump_p_1 PARAMS ((rtx *, void *));
-static void delete_prior_computation PARAMS ((rtx, rtx));
+static void init_label_info (rtx);
+static void mark_all_labels (rtx);
+static void delete_computation (rtx);
+static void redirect_exp_1 (rtx *, rtx, rtx, rtx);
+static int redirect_exp (rtx, rtx, rtx);
+static void invert_exp_1 (rtx);
+static int invert_exp (rtx);
+static int returnjump_p_1 (rtx *, void *);
+static void delete_prior_computation (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. */
void
-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;
+rebuild_jump_labels (rtx f)
{
- register rtx insn, next;
- int changed;
- int old_max_reg;
- int first = 1;
- int max_uid = 0;
- rtx last_insn;
-#ifdef HAVE_trap
- enum rtx_code reversed_code;
-#endif
-
- cross_jump_death_matters = (cross_jump == 2);
- max_uid = init_label_info (f) + 1;
-
- 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));
+ rtx insn;
- mark_all_labels (f, cross_jump);
+ timevar_push (TV_REBUILD_JUMP);
+ init_label_info (f);
+ 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
count doesn't drop to zero. */
for (insn = forced_labels; insn; insn = XEXP (insn, 1))
- if (GET_CODE (XEXP (insn, 0)) == CODE_LABEL)
+ if (LABEL_P (XEXP (insn, 0)))
LABEL_NUSES (XEXP (insn, 0))++;
-
- /* 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))
- if (GET_CODE (XEXP (insn, 0)) == CODE_LABEL)
- 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;
-
- last_insn = delete_unreferenced_labels (f);
-
- if (noop_moves)
- delete_noop_moves (f);
-
- /* Now iterate optimizing jumps until nothing changes over one pass. */
- changed = 1;
- old_max_reg = max_reg_num ();
- while (changed)
- {
- changed = 0;
-
- for (insn = f; insn; insn = next)
- {
- rtx reallabelprev;
- rtx temp, temp1, temp2 = NULL_RTX;
- rtx temp4 ATTRIBUTE_UNUSED;
- rtx nlabel;
- int this_is_any_uncondjump;
- int this_is_any_condjump;
- int this_is_onlyjump;
-
- 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
- && any_uncondjump_p (temp1)
- && onlyjump_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_any_condjump = any_condjump_p (insn);
- this_is_any_uncondjump = any_uncondjump_p (insn);
- this_is_onlyjump = onlyjump_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, 1);
-
- 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_any_condjump || this_is_any_uncondjump)
- && this_is_onlyjump)
- {
- 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_any_condjump && this_is_onlyjump
- && (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)
- {
- /* Ensure that we jump to the later of the two labels.
- Consider:
-
- if (test) goto L2;
- goto L1;
- ...
- L1:
- (clobber return-reg)
- L2:
- (use return-reg)
-
- If we leave the goto L1, we'll incorrectly leave
- return-reg dead for TEST true. */
-
- temp2 = next_active_insn (JUMP_LABEL (insn));
- if (!temp2)
- temp2 = get_last_insn ();
- if (GET_CODE (temp2) != CODE_LABEL)
- temp2 = prev_label (temp2);
- if (temp2 != JUMP_LABEL (temp))
- redirect_jump (temp, temp2, 1);
-
- delete_jump (insn);
- changed = 1;
- continue;
- }
- }
-
- /* Detect a conditional jump jumping over an unconditional jump. */
-
- else if (this_is_any_condjump
- && reallabelprev != 0
- && GET_CODE (reallabelprev) == JUMP_INSN
- && prev_active_insn (reallabelprev) == insn
- && no_labels_between_p (insn, reallabelprev)
- && any_uncondjump_p (reallabelprev)
- && onlyjump_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), 1))
- {
- /* 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_any_uncondjump
- && (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), 1);
- 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_any_condjump && this_is_onlyjump
- && 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))
- && ((reversed_code = reversed_comparison_code (temp2, insn))
- != UNKNOWN))
- {
- rtx new = gen_cond_trap (reversed_code,
- XEXP (temp2, 0), XEXP (temp2, 1),
- TRAP_CODE (PATTERN (reallabelprev)));
-
- 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_onlyjump
- && (temp = next_active_insn (JUMP_LABEL (insn)))
- && GET_CODE (temp) == INSN
- && GET_CODE (PATTERN (temp)) == TRAP_IF
- && (this_is_any_uncondjump
- || (this_is_any_condjump
- && (temp2 = get_condition (insn, &temp4)))))
- {
- rtx tc = TRAP_CONDITION (PATTERN (temp));
-
- if (tc == const_true_rtx
- || (! this_is_any_uncondjump && rtx_equal_p (temp2, tc)))
- {
- rtx new;
- /* Replace an unconditional jump to a trap with a trap. */
- if (this_is_any_uncondjump)
- {
- 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_any_condjump
- && 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), 1))
- {
- changed = 1;
- continue;
- }
- }
-#endif
- else
- {
- /* 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;
- }
- }
- }
- }
-
- first = 0;
- }
-
- /* 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)
- {
- 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_insn (insn);
- continue;
- }
-
- last_note = insn;
- }
- }
- }
-
-end:
- /* Clean up. */
- free (jump_chain);
- jump_chain = 0;
+ timevar_pop (TV_REBUILD_JUMP);
}
\f
-/* Initialize LABEL_NUSES and JUMP_LABEL fields. Delete any REG_LABEL
- notes whose labels don't occur in the insn any more. Returns the
- largest INSN_UID found. */
-static int
-init_label_info (f)
- rtx f;
-{
- int largest_uid = 0;
- rtx insn;
-
- for (insn = f; insn; insn = NEXT_INSN (insn))
- {
- if (GET_CODE (insn) == CODE_LABEL)
- LABEL_NUSES (insn) = (LABEL_PRESERVE_P (insn) != 0);
- else if (GET_CODE (insn) == JUMP_INSN)
- JUMP_LABEL (insn) = 0;
- else if (GET_CODE (insn) == INSN || GET_CODE (insn) == CALL_INSN)
- {
- rtx note, next;
-
- for (note = REG_NOTES (insn); note; note = next)
- {
- next = XEXP (note, 1);
- if (REG_NOTE_KIND (note) == REG_LABEL
- && ! reg_mentioned_p (XEXP (note, 0), PATTERN (insn)))
- remove_note (insn, note);
- }
- }
- if (INSN_UID (insn) > largest_uid)
- largest_uid = INSN_UID (insn);
- }
-
- 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;
+/* 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 (void)
{
- rtx insn;
- rtx set;
-
- for (insn = f; insn;)
+ rtx insn, next, prev;
+ for (insn = get_insns (); insn; insn = next)
{
- if (GET_CODE (insn) == BARRIER)
+ next = NEXT_INSN (insn);
+ if (BARRIER_P (insn))
{
- 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. */
+ prev = prev_nonnote_insn (insn);
+ if (BARRIER_P (prev))
+ delete_insn (insn);
+ else if (prev != PREV_INSN (insn))
+ reorder_insns (insn, insn, prev);
}
-
- /* 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
- && (set = pc_set (insn)) != NULL
- && SET_SRC (set) == pc_rtx
- && SET_DEST (set) == pc_rtx
- && onlyjump_p (insn))
- 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. */
-
-static void
-mark_all_labels (f, cross_jump)
- rtx f;
- int cross_jump;
+void
+purge_line_number_notes (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. */
for (insn = f; insn; insn = NEXT_INSN (insn))
- if (INSN_P (insn))
+ if (NOTE_P (insn))
{
- if (GET_CODE (insn) == CALL_INSN
- && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
+ 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)
{
- 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);
-
- /* 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, cross_jump, 0);
- XEXP (PATTERN (insn), 3) = XEXP (label_ref, 0);
- }
-
- continue;
- }
-
- mark_jump_label (PATTERN (insn), insn, cross_jump, 0);
- if (! INSN_DELETED_P (insn) && GET_CODE (insn) == JUMP_INSN)
- {
- /* 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)
- {
- 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, cross_jump, 0);
- XEXP (label_note, 0) = XEXP (label_ref, 0);
- JUMP_LABEL (insn) = XEXP (label_note, 0);
- }
- }
- 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)
+ /* Delete this note if it is identical to previous note. */
+ if (last_note
+#ifdef USE_MAPPED_LOCATION
+ && NOTE_SOURCE_LOCATION (insn) == NOTE_SOURCE_LOCATION (last_note)
+#else
+ && NOTE_SOURCE_FILE (insn) == NOTE_SOURCE_FILE (last_note)
+ && NOTE_LINE_NUMBER (insn) == NOTE_LINE_NUMBER (last_note)
+#endif
+)
{
- jump_chain[INSN_UID (insn)] = jump_chain[0];
- jump_chain[0] = insn;
+ delete_related_insns (insn);
+ continue;
}
- }
- }
-}
-
-/* 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_noop_p (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);
- }
- }
- insn = next;
- }
-}
-
-/* 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,
- followed by a jump to the exit of the loop. Then delete the unconditional
- jump after INSN.
-
- Return 1 if we made the change, else 0.
-
- This is only safe immediately after a regscan pass because it uses the
- values of regno_first_uid and regno_last_uid. */
-
-static int
-duplicate_loop_exit_test (loop_start)
- rtx loop_start;
-{
- rtx insn, set, reg, p, link;
- rtx copy = 0, first_copy = 0;
- int num_insns = 0;
- rtx exitcode = NEXT_INSN (JUMP_LABEL (next_nonnote_insn (loop_start)));
- rtx lastexit;
- int max_reg = max_reg_num ();
- rtx *reg_map = 0;
-
- /* Scan the exit code. We do not perform this optimization if any insn:
-
- is a CALL_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
- ASM_OPERANDS can confuse asm_noperands in some cases.
-
- Also, don't do this if the exit code is more than 20 insns. */
-
- for (insn = exitcode;
- insn
- && ! (GET_CODE (insn) == NOTE
- && NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_END);
- insn = NEXT_INSN (insn))
- {
- switch (GET_CODE (insn))
- {
- case CODE_LABEL:
- 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
- || NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END))
- /* If we were to duplicate this code, we would not move
- the BLOCK notes, and so debugging the moved code would
- be difficult. Thus, we only move the code with -O2 or
- higher. */
- return 0;
-
- break;
- case JUMP_INSN:
- case INSN:
- /* The code below would grossly mishandle REG_WAS_0 notes,
- so get rid of them here. */
- while ((p = find_reg_note (insn, REG_WAS_0, NULL_RTX)) != 0)
- remove_note (insn, p);
- if (++num_insns > 20
- || find_reg_note (insn, REG_RETVAL, NULL_RTX)
- || find_reg_note (insn, REG_LIBCALL, NULL_RTX))
- return 0;
- break;
- default:
- break;
- }
- }
-
- /* Unless INSN is zero, we can do the optimization. */
- if (insn == 0)
- return 0;
-
- lastexit = insn;
-
- /* See if any insn sets a register only used in the loop exit code and
- not a user variable. If so, replace it with a new register. */
- for (insn = exitcode; insn != lastexit; insn = NEXT_INSN (insn))
- if (GET_CODE (insn) == INSN
- && (set = single_set (insn)) != 0
- && ((reg = SET_DEST (set), GET_CODE (reg) == REG)
- || (GET_CODE (reg) == SUBREG
- && (reg = SUBREG_REG (reg), GET_CODE (reg) == REG)))
- && REGNO (reg) >= FIRST_PSEUDO_REGISTER
- && REGNO_FIRST_UID (REGNO (reg)) == INSN_UID (insn))
- {
- for (p = NEXT_INSN (insn); p != lastexit; p = NEXT_INSN (p))
- if (REGNO_LAST_UID (REGNO (reg)) == INSN_UID (p))
- break;
-
- if (p != lastexit)
- {
- /* We can do the replacement. Allocate reg_map if this is the
- first replacement we found. */
- if (reg_map == 0)
- reg_map = (rtx *) xcalloc (max_reg, sizeof (rtx));
- REG_LOOP_TEST_P (reg) = 1;
-
- reg_map[REGNO (reg)] = gen_reg_rtx (GET_MODE (reg));
+ last_note = insn;
}
}
+}
+\f
+/* Initialize LABEL_NUSES and JUMP_LABEL fields. Delete any REG_LABEL
+ notes whose labels don't occur in the insn any more. Returns the
+ largest INSN_UID found. */
+static void
+init_label_info (rtx f)
+{
+ rtx insn;
- /* Now copy each insn. */
- for (insn = exitcode; insn != lastexit; insn = NEXT_INSN (insn))
- {
- switch (GET_CODE (insn))
- {
- case BARRIER:
- copy = emit_barrier_before (loop_start);
- break;
- case NOTE:
- /* Only copy line-number notes. */
- if (NOTE_LINE_NUMBER (insn) >= 0)
- {
- copy = emit_note_before (NOTE_LINE_NUMBER (insn), loop_start);
- 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);
-
- /* 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_NOTE_KIND (link) != REG_LABEL)
- {
- if (GET_CODE (link) == EXPR_LIST)
- REG_NOTES (copy)
- = copy_insn_1 (gen_rtx_EXPR_LIST (REG_NOTE_KIND (link),
- XEXP (link, 0),
- REG_NOTES (copy)));
- else
- REG_NOTES (copy)
- = copy_insn_1 (gen_rtx_INSN_LIST (REG_NOTE_KIND (link),
- XEXP (link, 0),
- REG_NOTES (copy)));
- }
-
- 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);
- if (reg_map)
- replace_regs (PATTERN (copy), reg_map, max_reg, 1);
- mark_jump_label (PATTERN (copy), copy, 0, 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))
- {
- jump_chain[INSN_UID (copy)]
- = jump_chain[INSN_UID (JUMP_LABEL (copy))];
- jump_chain[INSN_UID (JUMP_LABEL (copy))] = copy;
- }
- break;
-
- default:
- abort ();
- }
-
- /* Record the first insn we copied. We need it so that we can
- scan the copied insns for new pseudo registers. */
- if (! first_copy)
- first_copy = copy;
- }
-
- /* Now clean up by emitting a jump to the end label and deleting the jump
- at the start of the loop. */
- if (! copy || GET_CODE (copy) != BARRIER)
- {
- copy = emit_jump_insn_before (gen_jump (get_label_after (insn)),
- loop_start);
-
- /* Record the first insn we copied. We need it so that we can
- scan the copied insns for new pseudo registers. This may not
- be strictly necessary since we should have copied at least one
- insn above. But I am going to be safe. */
- 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);
- }
+ for (insn = f; insn; insn = NEXT_INSN (insn))
+ if (LABEL_P (insn))
+ LABEL_NUSES (insn) = (LABEL_PRESERVE_P (insn) != 0);
+ else if (JUMP_P (insn))
+ JUMP_LABEL (insn) = 0;
+ else if (NONJUMP_INSN_P (insn) || CALL_P (insn))
+ {
+ rtx note, next;
- /* 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);
+ for (note = REG_NOTES (insn); note; note = next)
+ {
+ next = XEXP (note, 1);
+ if (REG_NOTE_KIND (note) == REG_LABEL
+ && ! reg_mentioned_p (XEXP (note, 0), PATTERN (insn)))
+ remove_note (insn, note);
+ }
+ }
+}
- /* Mark the exit code as the virtual top of the converted loop. */
- emit_note_before (NOTE_INSN_LOOP_VTOP, exitcode);
+/* Mark the label each jump jumps to.
+ Combine consecutive labels, and count uses of labels. */
- delete_insn (next_nonnote_insn (loop_start));
+static void
+mark_all_labels (rtx f)
+{
+ rtx insn;
- /* Clean up. */
- if (reg_map)
- free (reg_map);
+ for (insn = f; insn; insn = NEXT_INSN (insn))
+ if (INSN_P (insn))
+ {
+ mark_jump_label (PATTERN (insn), insn, 0);
+ if (! INSN_DELETED_P (insn) && JUMP_P (insn))
+ {
+ /* 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)
+ {
+ 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));
- return 1;
+ mark_jump_label (label_ref, insn, 0);
+ XEXP (label_note, 0) = XEXP (label_ref, 0);
+ JUMP_LABEL (insn) = XEXP (label_note, 0);
+ }
+ }
+ }
+ }
}
\f
/* Move all block-beg, block-end, loop-beg, loop-cont, loop-vtop, loop-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. */
+ 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. */
-rtx
-squeeze_notes (start, end)
- rtx start, end;
+bool
+squeeze_notes (rtx* startp, rtx* endp)
{
+ rtx start = *startp;
+ rtx end = *endp;
+
rtx insn;
rtx next;
+ rtx last = NULL;
+ rtx past_end = NEXT_INSN (end);
- for (insn = start; insn != end; insn = next)
+ for (insn = start; insn != past_end; insn = next)
{
next = NEXT_INSN (insn);
- if (GET_CODE (insn) == NOTE
+ if (NOTE_P (insn)
&& (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_LOOP_END))
{
if (insn == start)
start = next;
PREV_INSN (next) = prev;
}
}
+ else
+ last = insn;
}
- 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;
-
- 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
-
- /* 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;
- }
- }
-
- /* Insns fail to match; cross jumping is limited to the following
- insns. */
-
-#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
-
- /* 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;
- }
-
- 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;
- }
- }
-
- if (minimum <= 0 && last1 != 0 && last1 != e1)
- *f1 = last1, *f2 = last2;
-}
-
-static void
-do_cross_jump (insn, newjpos, newlpos)
- rtx insn, newjpos, newlpos;
-{
- /* Find an existing label at this point
- or make a new one if there is none. */
- register rtx label = get_label_before (newlpos);
-
- /* Make the same jump insn jump to the new point. */
- if (GET_CODE (PATTERN (insn)) == RETURN)
- {
- /* 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)
- {
- jump_chain[INSN_UID (insn)] = jump_chain[INSN_UID (label)];
- jump_chain[INSN_UID (label)] = insn;
- }
- }
- else
- redirect_jump (insn, label, 1);
+ /* There were no real instructions. */
+ if (start == past_end)
+ return true;
- /* 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. */
+ end = last;
- 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);
- }
+ *startp = start;
+ *endp = end;
+ return false;
}
\f
/* Return the label before INSN, or put a new label there. */
rtx
-get_label_before (insn)
- rtx insn;
+get_label_before (rtx insn)
{
rtx label;
or make a new one if there is none. */
label = prev_nonnote_insn (insn);
- if (label == 0 || GET_CODE (label) != CODE_LABEL)
+ if (label == 0 || !LABEL_P (label))
{
rtx prev = PREV_INSN (insn);
/* Return the label after INSN, or put a new label there. */
rtx
-get_label_after (insn)
- rtx insn;
+get_label_after (rtx insn)
{
rtx label;
or make a new one if there is none. */
label = next_nonnote_insn (insn);
- if (label == 0 || GET_CODE (label) != CODE_LABEL)
+ if (label == 0 || !LABEL_P (label))
{
label = gen_label_rtx ();
emit_label_after (label, insn);
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;
-{
- rtx cinsn, ctarget;
- enum rtx_code codei, codet;
- rtx set, tset;
-
- if (! any_condjump_p (insn)
- || any_uncondjump_p (target)
- || target != prev_real_insn (JUMP_LABEL (insn)))
- return 0;
- set = pc_set (insn);
- tset = pc_set (target);
-
- cinsn = XEXP (SET_SRC (set), 0);
- ctarget = XEXP (SET_SRC (tset), 0);
-
- codei = GET_CODE (cinsn);
- codet = GET_CODE (ctarget);
-
- if (XEXP (SET_SRC (set), 1) == pc_rtx)
- {
- codei = reversed_comparison_code (cinsn, insn);
- if (codei == UNKNOWN)
- return 0;
- }
-
- if (XEXP (SET_SRC (tset), 2) == pc_rtx)
- {
- codet = reversed_comparison_code (ctarget, target);
- if (codei == UNKNOWN)
- return 0;
- }
-
- 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 (CODE ARG0 ARG1), inside a insn, INSN, return an code
+/* 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;
+reversed_comparison_code_parts (enum rtx_code code, rtx arg0, rtx arg1, rtx insn)
{
enum machine_mode mode;
/* If this is not actually a comparison, we can't reverse it. */
- if (GET_RTX_CLASS (code) != '<')
+ if (GET_RTX_CLASS (code) != RTX_COMPARE
+ && GET_RTX_CLASS (code) != RTX_COMM_COMPARE)
return UNKNOWN;
mode = GET_MODE (arg0);
if (mode == VOIDmode)
mode = GET_MODE (arg1);
- /* 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
+ /* First see if machine description supplies us way to reverse the
+ comparison. Give it priority over everything else to allow
+ machine description to do tricks. */
if (GET_MODE_CLASS (mode) == MODE_CC
&& REVERSIBLE_CC_MODE (mode))
{
#ifdef REVERSE_CONDITION
- return REVERSE_CONDITION (code, mode);
-#endif
- return reverse_condition (code);
- }
+ return REVERSE_CONDITION (code, mode);
#endif
+ return reverse_condition (code);
+ }
- /* Try few special cases based on the comparison code. */
+ /* Try a few special cases based on the comparison code. */
switch (code)
{
- 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;
+ 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. Similarly 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;
}
- /* In case we give up IEEE compatibility, all comparisons are reversible. */
- if (TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT
- || flag_unsafe_math_optimizations)
- return reverse_condition (code);
-
- if (GET_MODE_CLASS (mode) == MODE_CC
-#ifdef HAVE_cc0
- || arg0 == cc0_rtx
-#endif
- )
+ if (GET_MODE_CLASS (mode) == MODE_CC || CC0_P (arg0))
{
rtx prev;
/* Try to search for the comparison to determine the real mode.
return UNKNOWN;
for (prev = prev_nonnote_insn (insn);
- prev != 0 && GET_CODE (prev) != CODE_LABEL;
+ prev != 0 && !LABEL_P (prev);
prev = prev_nonnote_insn (prev))
{
rtx set = set_of (arg0, prev);
mode = GET_MODE (XEXP (comparison, 1));
break;
}
- /* We can get past reg-reg moves. This may be usefull for model
+ /* 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))
{
}
}
- /* An integer condition. */
+ /* 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
- && ! FLOAT_MODE_P (mode)))
+ && !HONOR_NANS (mode)))
return reverse_condition (code);
return UNKNOWN;
}
-/* An wrapper around the previous function to take COMPARISON as rtx
+/* A 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;
+reversed_comparison_code (rtx comparison, rtx insn)
{
- if (GET_RTX_CLASS (GET_CODE (comparison)) != '<')
+ if (!COMPARISON_P (comparison))
return UNKNOWN;
return reversed_comparison_code_parts (GET_CODE (comparison),
XEXP (comparison, 0),
Use reversed_comparison_code instead. */
enum rtx_code
-reverse_condition (code)
- enum rtx_code code;
+reverse_condition (enum rtx_code code)
{
switch (code)
{
that the target will support them too... */
enum rtx_code
-reverse_condition_maybe_unordered (code)
- enum rtx_code code;
+reverse_condition_maybe_unordered (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:
This IS safe for IEEE floating-point. */
enum rtx_code
-swap_condition (code)
- enum rtx_code code;
+swap_condition (enum rtx_code code)
{
switch (code)
{
CODE is returned. */
enum rtx_code
-unsigned_condition (code)
- enum rtx_code code;
+unsigned_condition (enum rtx_code code)
{
switch (code)
{
/* Similarly, return the signed version of a comparison. */
enum rtx_code
-signed_condition (code)
- enum rtx_code code;
+signed_condition (enum rtx_code code)
{
switch (code)
{
}
}
\f
-/* Return non-zero if CODE1 is more strict than CODE2, i.e., if the
+/* Return nonzero if CODE1 is more strict than CODE2, i.e., if the
truth of CODE1 implies the truth of CODE2. */
int
-comparison_dominates_p (code1, code2)
- enum rtx_code code1, code2;
+comparison_dominates_p (enum rtx_code code1, enum rtx_code code2)
{
/* UNKNOWN comparison codes can happen as a result of trying to revert
comparison codes.
/* Return 1 if INSN is an unconditional jump and nothing else. */
int
-simplejump_p (insn)
- rtx insn;
+simplejump_p (rtx insn)
{
- return (GET_CODE (insn) == JUMP_INSN
+ return (JUMP_P (insn)
&& GET_CODE (PATTERN (insn)) == SET
&& GET_CODE (SET_DEST (PATTERN (insn))) == PC
&& GET_CODE (SET_SRC (PATTERN (insn))) == LABEL_REF);
/* Return nonzero if INSN is a (possibly) conditional jump
and nothing more.
- Use this function is deprecated, since we need to support combined
+ Use of this function is deprecated, since we need to support combined
branch and compare insns. Use any_condjump_p instead whenever possible. */
int
-condjump_p (insn)
- rtx insn;
+condjump_p (rtx insn)
{
- register rtx x = PATTERN (insn);
+ rtx x = PATTERN (insn);
if (GET_CODE (x) != SET
|| GET_CODE (SET_DEST (x)) != PC)
|| (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
branch and compare insns. Use any_condjump_p instead whenever possible. */
int
-condjump_in_parallel_p (insn)
- rtx insn;
+condjump_in_parallel_p (rtx insn)
{
- register rtx x = PATTERN (insn);
+ rtx x = PATTERN (insn);
if (GET_CODE (x) != PARALLEL)
return 0;
/* Return set of PC, otherwise NULL. */
rtx
-pc_set (insn)
- rtx insn;
+pc_set (rtx insn)
{
rtx pat;
- if (GET_CODE (insn) != JUMP_INSN)
+ if (!JUMP_P (insn))
return NULL_RTX;
pat = PATTERN (insn);
possibly bundled inside a PARALLEL. */
int
-any_uncondjump_p (insn)
- rtx insn;
+any_uncondjump_p (rtx insn)
{
rtx x = pc_set (insn);
if (!x)
return 0;
if (GET_CODE (SET_SRC (x)) != LABEL_REF)
return 0;
+ if (find_reg_note (insn, REG_NON_LOCAL_GOTO, NULL_RTX))
+ return 0;
return 1;
}
Note that unlike condjump_p it returns false for unconditional jumps. */
int
-any_condjump_p (insn)
- rtx insn;
+any_condjump_p (rtx insn)
{
rtx x = pc_set (insn);
enum rtx_code a, b;
/* Return the label of a conditional jump. */
rtx
-condjump_label (insn)
- rtx insn;
+condjump_label (rtx insn)
{
rtx x = pc_set (insn);
/* Return true if INSN is a (possibly conditional) return insn. */
static int
-returnjump_p_1 (loc, data)
- rtx *loc;
- void *data ATTRIBUTE_UNUSED;
+returnjump_p_1 (rtx *loc, 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
-returnjump_p (insn)
- rtx insn;
+returnjump_p (rtx insn)
{
- if (GET_CODE (insn) != JUMP_INSN)
+ if (!JUMP_P (insn))
return 0;
return for_each_rtx (&PATTERN (insn), returnjump_p_1, NULL);
}
nothing more. */
int
-onlyjump_p (insn)
- rtx insn;
+onlyjump_p (rtx insn)
{
rtx set;
- if (GET_CODE (insn) != JUMP_INSN)
+ if (!JUMP_P (insn))
return 0;
set = single_set (insn);
#ifdef HAVE_cc0
+/* Return nonzero if X is an RTX that only sets the condition codes
+ and has no side effects. */
+
+int
+only_sets_cc0_p (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,
but also does other things. */
int
-sets_cc0_p (x)
- rtx x ATTRIBUTE_UNUSED;
+sets_cc0_p (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)
\f
/* Follow any unconditional jump at LABEL;
return the ultimate label reached by any such chain of jumps.
+ Return null if the chain ultimately leads to a return instruction.
If LABEL is not followed by a jump, return LABEL.
If the chain loops or we can't find end, return LABEL,
since that tells caller to avoid changing the insn.
a USE or CLOBBER. */
rtx
-follow_jumps (label)
- rtx label;
+follow_jumps (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_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);
+ && BARRIER_P (next));
depth++)
{
/* Don't chain through the insn that jumps into a loop
rtx tem;
if (!reload_completed)
for (tem = value; tem != insn; tem = NEXT_INSN (tem))
- if (GET_CODE (tem) == NOTE
+ if (NOTE_P (tem)
&& (NOTE_LINE_NUMBER (tem) == NOTE_INSN_LOOP_BEG
/* ??? Optional. Disables some optimizations, but makes
gcov output more accurate with -O. */
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.
-
- 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. */
+ that loop-optimization is done with. */
void
-mark_jump_label (x, insn, cross_jump, in_mem)
- register rtx x;
- rtx insn;
- int cross_jump;
- int in_mem;
+mark_jump_label (rtx x, rtx insn, 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 PC:
case CC0:
case REG:
- case SUBREG:
case CONST_INT:
case CONST_DOUBLE:
case CLOBBER:
/* 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 (NOTE_P (label)
&& NOTE_LINE_NUMBER (label) == NOTE_INSN_DELETED_LABEL)
break;
- if (GET_CODE (label) != CODE_LABEL)
+ if (!LABEL_P (label))
abort ();
/* Ignore references to labels of containing functions. */
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 (insn)
{
- if (GET_CODE (insn) == JUMP_INSN)
+ if (JUMP_P (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;
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);
}
}
}
if that's what the previous thing was. */
void
-delete_jump (insn)
- rtx insn;
+delete_jump (rtx insn)
{
- register rtx set = single_set (insn);
+ rtx set = single_set (insn);
if (set && GET_CODE (SET_DEST (set)) == PC)
delete_computation (insn);
}
-/* Verify INSN is a BARRIER and delete it. */
-
-void
-delete_barrier (insn)
- rtx insn;
-{
- if (GET_CODE (insn) != BARRIER)
- abort ();
-
- delete_insn (insn);
-}
-
/* Recursively delete prior insns that compute the value (used only by INSN
which the caller is deleting) stored in the register mentioned by NOTE
which is a REG_DEAD note associated with INSN. */
static void
-delete_prior_computation (note, insn)
- rtx note;
- rtx insn;
+delete_prior_computation (rtx note, rtx insn)
{
rtx our_prev;
rtx reg = XEXP (note, 0);
for (our_prev = prev_nonnote_insn (insn);
- our_prev && (GET_CODE (our_prev) == INSN
- || GET_CODE (our_prev) == CALL_INSN);
+ our_prev && (NONJUMP_INSN_P (our_prev)
+ || CALL_P (our_prev));
our_prev = prev_nonnote_insn (our_prev))
{
rtx pat = PATTERN (our_prev);
/* 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)
+ if (CALL_P (our_prev)
+ && (! CONST_OR_PURE_CALL_P (our_prev)
|| GET_CODE (pat) != SET || GET_CODE (SET_SRC (pat)) != CALL))
break;
/* If we reach a SEQUENCE, it is too complex to try to
- do anything with it, so give up. */
+ do anything with it, so give up. We can be run during
+ and after reorg, so SEQUENCE rtl can legitimately show
+ up here. */
if (GET_CODE (pat) == SEQUENCE)
break;
if (GET_CODE (pat) == USE
- && GET_CODE (XEXP (pat, 0)) == INSN)
+ && NONJUMP_INSN_P (XEXP (pat, 0)))
/* reorg creates USEs that look like this. We leave them
alone because reorg needs them for its own purposes. */
break;
if (reg_set_p (reg, pat))
{
- if (side_effects_p (pat) && GET_CODE (our_prev) != CALL_INSN)
+ if (side_effects_p (pat) && !CALL_P (our_prev))
break;
if (GET_CODE (pat) == PARALLEL)
delete_computation (our_prev);
}
else if (GET_CODE (pat) == SET
- && GET_CODE (SET_DEST (pat)) == REG)
+ && REG_P (SET_DEST (pat)))
{
int dest_regno = REGNO (SET_DEST (pat));
int dest_endregno
= (dest_regno
+ (dest_regno < FIRST_PSEUDO_REGISTER
- ? HARD_REGNO_NREGS (dest_regno,
- GET_MODE (SET_DEST (pat))) : 1));
+ ? hard_regno_nregs[dest_regno]
+ [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));
+ ? hard_regno_nregs[regno][GET_MODE (reg)] : 1));
if (dest_regno >= regno
&& dest_endregno <= endregno)
delete the insn that set it. */
static void
-delete_computation (insn)
- rtx insn;
+delete_computation (rtx insn)
{
rtx note, next;
will use them. So if the previous insn
exists to set the CC's, delete it
(unless it performs auto-increments, etc.). */
- if (prev && GET_CODE (prev) == INSN
+ if (prev && NONJUMP_INSN_P (prev)
&& sets_cc0_p (PATTERN (prev)))
{
if (sets_cc0_p (PATTERN (prev)) > 0
if (REG_NOTE_KIND (note) != REG_DEAD
/* Verify that the REG_NOTE is legitimate. */
- || GET_CODE (XEXP (note, 0)) != REG)
+ || !REG_P (XEXP (note, 0)))
continue;
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 (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 = (LABEL_P (insn));
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)
- {
- 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);
- }
+ if (next != 0 && BARRIER_P (next))
+ delete_insn (next);
/* If deleting a jump, decrement the count of the label,
and delete the label if it is now unused. */
- if (GET_CODE (insn) == JUMP_INSN && JUMP_LABEL (insn))
+ if (JUMP_P (insn) && JUMP_LABEL (insn))
{
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
next = NEXT_INSN (next);
return next;
}
- else if ((lab_next = next_nonnote_insn (lab)) != NULL
- && GET_CODE (lab_next) == JUMP_INSN
- && (GET_CODE (PATTERN (lab_next)) == ADDR_VEC
- || GET_CODE (PATTERN (lab_next)) == ADDR_DIFF_VEC))
+ else if (tablejump_p (insn, NULL, &lab_next))
{
/* 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);
}
}
/* Likewise if we're deleting a dispatch table. */
- if (GET_CODE (insn) == JUMP_INSN
+ if (JUMP_P (insn)
&& (GET_CODE (PATTERN (insn)) == ADDR_VEC
|| GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC))
{
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)
+ if (NONJUMP_INSN_P (insn) || CALL_P (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_insn (XEXP (note, 0));
+ && LABEL_P (XEXP (note, 0)))
+ if (LABEL_NUSES (XEXP (note, 0)) == 0)
+ delete_related_insns (XEXP (note, 0));
- while (prev && (INSN_DELETED_P (prev) || GET_CODE (prev) == NOTE))
+ while (prev && (INSN_DELETED_P (prev) || NOTE_P (prev)))
prev = PREV_INSN (prev);
/* If INSN was a label and a dispatch table follows it,
if (was_code_label
&& NEXT_INSN (insn) != 0
- && GET_CODE (NEXT_INSN (insn)) == JUMP_INSN
+ && JUMP_P (NEXT_INSN (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)
+ if (was_code_label && prev && BARRIER_P (prev))
{
- register RTX_CODE code;
- while (next != 0
- && (GET_RTX_CLASS (code = GET_CODE (next)) == 'i'
- || code == NOTE || code == BARRIER
- || (code == CODE_LABEL && INSN_DELETED_P (next))))
+ enum rtx_code code;
+ while (next)
{
+ code = GET_CODE (next);
if (code == NOTE
&& NOTE_LINE_NUMBER (next) != NOTE_INSN_FUNCTION_END)
next = NEXT_INSN (next);
/* Keep going past other deleted labels to delete what follows. */
else if (code == CODE_LABEL && INSN_DELETED_P (next))
next = NEXT_INSN (next);
- else
+ else if (code == BARRIER || INSN_P (next))
/* Note: if this deletes a jump, it can cause more
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);
+ else
+ break;
}
}
return next;
}
-
-/* Advance from INSN till reaching something not deleted
- then return that. May return INSN itself. */
-
-rtx
-next_nondeleted_insn (insn)
- rtx insn;
-{
- while (INSN_DELETED_P (insn))
- insn = NEXT_INSN (insn);
- return insn;
-}
\f
/* Delete a range of insns from FROM to TO, inclusive.
This is for the sake of peephole optimization, so assume
peephole insn that will replace them. */
void
-delete_for_peephole (from, to)
- register rtx from, to;
+delete_for_peephole (rtx from, rtx 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)
+ if (!NOTE_P (insn))
{
INSN_DELETED_P (insn) = 1;
is also an unconditional jump in that case. */
}
\f
-/* We have determined that INSN is never reached, and are about to
- delete it. Print a warning if the user asked for one.
-
- To try to make this warning more useful, this should only be called
- once per basic block not reached, and it only warns when the basic
- block contains more than one line from the current function, and
- contains at least one operation. CSE and inlining can duplicate insns,
- so it's possible to get spurious warnings from this. */
-
-void
-never_reached_warning (avoided_insn)
- rtx avoided_insn;
-{
- rtx insn;
- rtx a_line_note = NULL;
- int two_avoided_lines = 0;
- int contains_insn = 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 (a_line_note == NULL)
- a_line_note = insn;
- else
- two_avoided_lines |= (NOTE_LINE_NUMBER (a_line_note)
- != NOTE_LINE_NUMBER (insn));
- }
- else if (INSN_P (insn))
- contains_insn = 1;
- }
- if (two_avoided_lines && contains_insn)
- warning_with_file_and_line (NOTE_SOURCE_FILE (a_line_note),
- NOTE_LINE_NUMBER (a_line_note),
- "will never be executed");
-}
-\f
/* Throughout LOC, redirect OLABEL to NLABEL. Treat null OLABEL or
NLABEL as a return. Accrue modifications into the change group. */
static void
-redirect_exp_1 (loc, olabel, nlabel, insn)
- rtx *loc;
- rtx olabel, nlabel;
- rtx insn;
+redirect_exp_1 (rtx *loc, rtx olabel, rtx 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)
{
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. */
static int
-redirect_exp (olabel, nlabel, insn)
- rtx olabel, nlabel;
- rtx insn;
+redirect_exp (rtx olabel, rtx nlabel, rtx insn)
{
rtx *loc;
not see how to do that. */
int
-redirect_jump_1 (jump, nlabel)
- rtx jump, nlabel;
+redirect_jump_1 (rtx jump, rtx nlabel)
{
int ochanges = num_validated_changes ();
rtx *loc;
(this can only occur for NLABEL == 0). */
int
-redirect_jump (jump, nlabel, delete_unused)
- rtx jump, nlabel;
- int delete_unused;
+redirect_jump (rtx jump, rtx nlabel, int delete_unused)
{
- register rtx olabel = JUMP_LABEL (jump);
+ rtx olabel = JUMP_LABEL (jump);
+ rtx note;
if (nlabel == olabel)
return 1;
if (! redirect_exp (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;
+ JUMP_LABEL (jump) = nlabel;
+ if (nlabel)
+ ++LABEL_NUSES (nlabel);
- delete_from_jump_chain (jump);
- if (label_index < max_jump_chain
- && INSN_UID (jump) < max_jump_chain)
+ /* Update labels in any REG_EQUAL note. */
+ if ((note = find_reg_note (jump, REG_EQUAL, NULL_RTX)) != NULL_RTX)
+ {
+ if (nlabel && olabel)
{
- jump_chain[INSN_UID (jump)] = jump_chain[label_index];
- jump_chain[label_index] = jump;
+ rtx dest = XEXP (note, 0);
+
+ if (GET_CODE (dest) == IF_THEN_ELSE)
+ {
+ if (GET_CODE (XEXP (dest, 1)) == LABEL_REF
+ && XEXP (XEXP (dest, 1), 0) == olabel)
+ XEXP (XEXP (dest, 1), 0) = nlabel;
+ if (GET_CODE (XEXP (dest, 2)) == LABEL_REF
+ && XEXP (XEXP (dest, 2), 0) == olabel)
+ XEXP (XEXP (dest, 2), 0) = nlabel;
+ }
+ else
+ remove_note (jump, note);
}
+ else
+ remove_note (jump, note);
}
- JUMP_LABEL (jump) = nlabel;
- if (nlabel)
- ++LABEL_NUSES (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 && nlabel
&& NEXT_INSN (olabel)
- && GET_CODE (NEXT_INSN (olabel)) == NOTE
+ && NOTE_P (NEXT_INSN (olabel))
&& 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_unused)
- 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;
}
Accrue the modifications into the change group. */
static void
-invert_exp_1 (insn)
- rtx insn;
+invert_exp_1 (rtx insn)
{
- register RTX_CODE code;
+ RTX_CODE code;
rtx x = pc_set (insn);
if (!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
matches a pattern. */
static int
-invert_exp (insn)
- rtx insn;
+invert_exp (rtx insn)
{
invert_exp_1 (insn);
if (num_validated_changes () == 0)
inversion and redirection. */
int
-invert_jump_1 (jump, nlabel)
- rtx jump, nlabel;
+invert_jump_1 (rtx jump, rtx nlabel)
{
int ochanges;
NLABEL instead of where it jumps now. Return true if successful. */
int
-invert_jump (jump, nlabel, delete_unused)
- rtx jump, nlabel;
- int delete_unused;
+invert_jump (rtx jump, rtx 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
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);
+ /* Remove REG_EQUAL note if we have one. */
+ rtx note = find_reg_note (jump, REG_EQUAL, NULL_RTX);
if (note)
- XEXP (note, 0) = GEN_INT (REG_BR_PROB_BASE - INTVAL (XEXP (note, 0)));
+ remove_note (jump, note);
+
+ invert_br_probabilities (jump);
return 1;
}
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);
- rtx *notep, note, next;
-
- /* 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;
- }
-
- for (notep = ®_NOTES (jump), note = *notep; note; note = next)
- {
- next = XEXP (note, 1);
-
- if (REG_NOTE_KIND (note) != REG_DEAD
- /* Verify that the REG_NOTE is legitimate. */
- || GET_CODE (XEXP (note, 0)) != REG
- || ! reg_mentioned_p (XEXP (note, 0), PATTERN (jump)))
- notep = &XEXP (note, 1);
- else
- {
- delete_prior_computation (note, jump);
- *notep = next;
- }
- }
-
- 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
case when the PLUS is inside a MEM. */
int
-rtx_renumbered_equal_p (x, y)
- rtx x, y;
+rtx_renumbered_equal_p (rtx x, rtx y)
{
- register int i;
- register RTX_CODE code = GET_CODE (x);
- register const char *fmt;
+ int i;
+ enum rtx_code code = GET_CODE (x);
+ const char *fmt;
if (x == y)
return 1;
- if ((code == REG || (code == SUBREG && GET_CODE (SUBREG_REG (x)) == REG))
- && (GET_CODE (y) == REG || (GET_CODE (y) == SUBREG
- && GET_CODE (SUBREG_REG (y)) == REG)))
+ if ((code == REG || (code == SUBREG && REG_P (SUBREG_REG (x))))
+ && (REG_P (y) || (GET_CODE (y) == SUBREG
+ && REG_P (SUBREG_REG (y)))))
{
int reg_x = -1, reg_y = -1;
int byte_x = 0, byte_y = 0;
case CC0:
case ADDR_VEC:
case ADDR_DIFF_VEC:
- return 0;
-
case CONST_INT:
- return INTVAL (x) == INTVAL (y);
+ return 0;
case LABEL_REF:
/* We can't assume nonlocal labels have their following insns yet. */
order. Also handle the simple binary and unary cases without a loop.
??? Don't consider PLUS a commutative operator; see comments above. */
- if ((code == EQ || code == NE || GET_RTX_CLASS (code) == 'c')
- && code != PLUS)
+ if (COMMUTATIVE_P (x) && code != PLUS)
return ((rtx_renumbered_equal_p (XEXP (x, 0), XEXP (y, 0))
&& rtx_renumbered_equal_p (XEXP (x, 1), XEXP (y, 1)))
|| (rtx_renumbered_equal_p (XEXP (x, 0), XEXP (y, 1))
&& rtx_renumbered_equal_p (XEXP (x, 1), XEXP (y, 0))));
- else if (GET_RTX_CLASS (code) == '<' || GET_RTX_CLASS (code) == '2')
+ else if (NON_COMMUTATIVE_P (x))
return (rtx_renumbered_equal_p (XEXP (x, 0), XEXP (y, 0))
&& rtx_renumbered_equal_p (XEXP (x, 1), XEXP (y, 1)));
- else if (GET_RTX_CLASS (code) == '1')
+ else if (UNARY_P (x))
return rtx_renumbered_equal_p (XEXP (x, 0), XEXP (y, 0));
/* Compare the elements. If any pair of corresponding elements
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;
case 'u':
if (XEXP (x, i) != XEXP (y, i))
return 0;
- /* fall through. */
+ /* Fall through. */
case '0':
break;
return -1. Any rtx is valid for X. */
int
-true_regnum (x)
- rtx x;
+true_regnum (rtx x)
{
- if (GET_CODE (x) == REG)
+ if (REG_P (x))
{
if (REGNO (x) >= FIRST_PSEUDO_REGISTER && reg_renumber[REGNO (x)] >= 0)
return reg_renumber[REGNO (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;
- enum rtx_code reversed_code1, reversed_code2;
-
- /* 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))
- {
- rtx set;
- rtx set2;
-
- /* Get to a candidate branch insn. */
- if (GET_CODE (b1) != JUMP_INSN
- || ! any_condjump_p (b1) || JUMP_LABEL (b1) == 0)
- continue;
-
- memset (modified_regs, 0, max_reg * sizeof (char));
- modified_mem = 0;
-
- memcpy (same_regs, all_reset, 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 (any_uncondjump_p (b2)
- && onlyjump_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
- || !any_condjump_p (b2)
- || !onlyjump_p (b2))
- continue;
- set = pc_set (b1);
- set2 = pc_set (b2);
-
- /* 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 (set), 0), 0);
- b1op1 = XEXP (XEXP (SET_SRC (set), 0), 1);
- code1 = GET_CODE (XEXP (SET_SRC (set), 0));
- reversed_code1 = code1;
- if (XEXP (SET_SRC (set), 1) == pc_rtx)
- code1 = reversed_comparison_code (XEXP (SET_SRC (set), 0), b1);
- else
- reversed_code1 = reversed_comparison_code (XEXP (SET_SRC (set), 0), b1);
-
- b2op0 = XEXP (XEXP (SET_SRC (set2), 0), 0);
- b2op1 = XEXP (XEXP (SET_SRC (set2), 0), 1);
- code2 = GET_CODE (XEXP (SET_SRC (set2), 0));
- reversed_code2 = code2;
- if (XEXP (SET_SRC (set2), 1) == pc_rtx)
- code2 = reversed_comparison_code (XEXP (SET_SRC (set2), 0), b2);
- else
- reversed_code2 = reversed_comparison_code (XEXP (SET_SRC (set2), 0), b2);
-
- /* 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)
- || comparison_dominates_p (code1, reversed_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, 1);
- }
- 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;
+/* Return regno of the register REG and handle subregs too. */
+unsigned int
+reg_or_subregno (rtx reg)
{
- 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_unsafe_math_optimizations)
- 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;
+ if (REG_P (reg))
+ return REGNO (reg);
+ if (GET_CODE (reg) == SUBREG)
+ return REGNO (SUBREG_REG (reg));
+ abort ();
}
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