2373 lines
62 KiB
C
2373 lines
62 KiB
C
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/* Common subexpression elimination library for GNU compiler.
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Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
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1999, 2000, 2001, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
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Free Software Foundation, Inc.
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This file is part of GCC.
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GCC is free software; you can redistribute it and/or modify it under
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the terms of the GNU General Public License as published by the Free
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Software Foundation; either version 3, or (at your option) any later
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version.
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GCC is distributed in the hope that it will be useful, but WITHOUT ANY
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WARRANTY; without even the implied warranty of MERCHANTABILITY or
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FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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for more details.
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You should have received a copy of the GNU General Public License
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along with GCC; see the file COPYING3. If not see
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<http://www.gnu.org/licenses/>. */
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#include "config.h"
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#include "system.h"
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#include "coretypes.h"
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#include "tm.h"
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#include "rtl.h"
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#include "tm_p.h"
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#include "regs.h"
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#include "hard-reg-set.h"
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#include "flags.h"
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#include "real.h"
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#include "insn-config.h"
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#include "recog.h"
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#include "function.h"
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#include "emit-rtl.h"
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#include "toplev.h"
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#include "output.h"
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#include "ggc.h"
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#include "hashtab.h"
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#include "tree-pass.h"
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#include "cselib.h"
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#include "params.h"
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#include "alloc-pool.h"
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#include "target.h"
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static bool cselib_record_memory;
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static bool cselib_preserve_constants;
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static int entry_and_rtx_equal_p (const void *, const void *);
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static hashval_t get_value_hash (const void *);
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static struct elt_list *new_elt_list (struct elt_list *, cselib_val *);
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static struct elt_loc_list *new_elt_loc_list (struct elt_loc_list *, rtx);
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static void unchain_one_value (cselib_val *);
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static void unchain_one_elt_list (struct elt_list **);
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static void unchain_one_elt_loc_list (struct elt_loc_list **);
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static int discard_useless_locs (void **, void *);
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static int discard_useless_values (void **, void *);
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static void remove_useless_values (void);
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static unsigned int cselib_hash_rtx (rtx, int);
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static cselib_val *new_cselib_val (unsigned int, enum machine_mode, rtx);
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static void add_mem_for_addr (cselib_val *, cselib_val *, rtx);
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static cselib_val *cselib_lookup_mem (rtx, int);
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static void cselib_invalidate_regno (unsigned int, enum machine_mode);
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static void cselib_invalidate_mem (rtx);
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static void cselib_record_set (rtx, cselib_val *, cselib_val *);
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static void cselib_record_sets (rtx);
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struct expand_value_data
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{
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bitmap regs_active;
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cselib_expand_callback callback;
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void *callback_arg;
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bool dummy;
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};
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static rtx cselib_expand_value_rtx_1 (rtx, struct expand_value_data *, int);
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/* There are three ways in which cselib can look up an rtx:
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- for a REG, the reg_values table (which is indexed by regno) is used
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- for a MEM, we recursively look up its address and then follow the
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addr_list of that value
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- for everything else, we compute a hash value and go through the hash
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table. Since different rtx's can still have the same hash value,
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this involves walking the table entries for a given value and comparing
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the locations of the entries with the rtx we are looking up. */
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/* A table that enables us to look up elts by their value. */
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static htab_t cselib_hash_table;
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/* This is a global so we don't have to pass this through every function.
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It is used in new_elt_loc_list to set SETTING_INSN. */
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static rtx cselib_current_insn;
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/* The unique id that the next create value will take. */
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static unsigned int next_uid;
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/* The number of registers we had when the varrays were last resized. */
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static unsigned int cselib_nregs;
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/* Count values without known locations, or with only locations that
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wouldn't have been known except for debug insns. Whenever this
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grows too big, we remove these useless values from the table.
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Counting values with only debug values is a bit tricky. We don't
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want to increment n_useless_values when we create a value for a
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debug insn, for this would get n_useless_values out of sync, but we
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want increment it if all locs in the list that were ever referenced
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in nondebug insns are removed from the list.
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In the general case, once we do that, we'd have to stop accepting
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nondebug expressions in the loc list, to avoid having two values
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equivalent that, without debug insns, would have been made into
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separate values. However, because debug insns never introduce
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equivalences themselves (no assignments), the only means for
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growing loc lists is through nondebug assignments. If the locs
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also happen to be referenced in debug insns, it will work just fine.
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A consequence of this is that there's at most one debug-only loc in
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each loc list. If we keep it in the first entry, testing whether
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we have a debug-only loc list takes O(1).
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Furthermore, since any additional entry in a loc list containing a
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debug loc would have to come from an assignment (nondebug) that
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references both the initial debug loc and the newly-equivalent loc,
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the initial debug loc would be promoted to a nondebug loc, and the
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loc list would not contain debug locs any more.
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So the only case we have to be careful with in order to keep
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n_useless_values in sync between debug and nondebug compilations is
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to avoid incrementing n_useless_values when removing the single loc
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from a value that turns out to not appear outside debug values. We
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increment n_useless_debug_values instead, and leave such values
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alone until, for other reasons, we garbage-collect useless
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values. */
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static int n_useless_values;
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static int n_useless_debug_values;
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/* Count values whose locs have been taken exclusively from debug
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insns for the entire life of the value. */
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static int n_debug_values;
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/* Number of useless values before we remove them from the hash table. */
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#define MAX_USELESS_VALUES 32
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/* This table maps from register number to values. It does not
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contain pointers to cselib_val structures, but rather elt_lists.
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The purpose is to be able to refer to the same register in
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different modes. The first element of the list defines the mode in
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which the register was set; if the mode is unknown or the value is
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no longer valid in that mode, ELT will be NULL for the first
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element. */
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static struct elt_list **reg_values;
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static unsigned int reg_values_size;
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#define REG_VALUES(i) reg_values[i]
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/* The largest number of hard regs used by any entry added to the
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REG_VALUES table. Cleared on each cselib_clear_table() invocation. */
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static unsigned int max_value_regs;
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/* Here the set of indices I with REG_VALUES(I) != 0 is saved. This is used
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in cselib_clear_table() for fast emptying. */
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static unsigned int *used_regs;
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static unsigned int n_used_regs;
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/* We pass this to cselib_invalidate_mem to invalidate all of
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memory for a non-const call instruction. */
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static GTY(()) rtx callmem;
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/* Set by discard_useless_locs if it deleted the last location of any
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value. */
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static int values_became_useless;
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/* Used as stop element of the containing_mem list so we can check
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presence in the list by checking the next pointer. */
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static cselib_val dummy_val;
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/* If non-NULL, value of the eliminated arg_pointer_rtx or frame_pointer_rtx
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that is constant through the whole function and should never be
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eliminated. */
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static cselib_val *cfa_base_preserved_val;
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/* Used to list all values that contain memory reference.
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May or may not contain the useless values - the list is compacted
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each time memory is invalidated. */
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static cselib_val *first_containing_mem = &dummy_val;
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static alloc_pool elt_loc_list_pool, elt_list_pool, cselib_val_pool, value_pool;
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/* If nonnull, cselib will call this function before freeing useless
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VALUEs. A VALUE is deemed useless if its "locs" field is null. */
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void (*cselib_discard_hook) (cselib_val *);
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/* If nonnull, cselib will call this function before recording sets or
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even clobbering outputs of INSN. All the recorded sets will be
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represented in the array sets[n_sets]. new_val_min can be used to
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tell whether values present in sets are introduced by this
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instruction. */
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void (*cselib_record_sets_hook) (rtx insn, struct cselib_set *sets,
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int n_sets);
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#define PRESERVED_VALUE_P(RTX) \
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(RTL_FLAG_CHECK1("PRESERVED_VALUE_P", (RTX), VALUE)->unchanging)
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/* Allocate a struct elt_list and fill in its two elements with the
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arguments. */
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static inline struct elt_list *
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new_elt_list (struct elt_list *next, cselib_val *elt)
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{
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struct elt_list *el;
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el = (struct elt_list *) pool_alloc (elt_list_pool);
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el->next = next;
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el->elt = elt;
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return el;
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}
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/* Allocate a struct elt_loc_list and fill in its two elements with the
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arguments. */
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static inline struct elt_loc_list *
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new_elt_loc_list (struct elt_loc_list *next, rtx loc)
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{
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struct elt_loc_list *el;
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el = (struct elt_loc_list *) pool_alloc (elt_loc_list_pool);
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el->next = next;
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el->loc = loc;
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el->setting_insn = cselib_current_insn;
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gcc_assert (!next || !next->setting_insn
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|| !DEBUG_INSN_P (next->setting_insn));
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/* If we're creating the first loc in a debug insn context, we've
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just created a debug value. Count it. */
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if (!next && cselib_current_insn && DEBUG_INSN_P (cselib_current_insn))
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n_debug_values++;
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return el;
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}
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/* Promote loc L to a nondebug cselib_current_insn if L is marked as
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originating from a debug insn, maintaining the debug values
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count. */
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static inline void
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promote_debug_loc (struct elt_loc_list *l)
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{
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if (l->setting_insn && DEBUG_INSN_P (l->setting_insn)
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&& (!cselib_current_insn || !DEBUG_INSN_P (cselib_current_insn)))
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{
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n_debug_values--;
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l->setting_insn = cselib_current_insn;
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gcc_assert (!l->next);
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}
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}
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/* The elt_list at *PL is no longer needed. Unchain it and free its
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storage. */
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static inline void
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unchain_one_elt_list (struct elt_list **pl)
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{
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struct elt_list *l = *pl;
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*pl = l->next;
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pool_free (elt_list_pool, l);
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}
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/* Likewise for elt_loc_lists. */
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static void
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unchain_one_elt_loc_list (struct elt_loc_list **pl)
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{
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struct elt_loc_list *l = *pl;
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*pl = l->next;
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pool_free (elt_loc_list_pool, l);
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}
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/* Likewise for cselib_vals. This also frees the addr_list associated with
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V. */
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static void
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unchain_one_value (cselib_val *v)
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{
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while (v->addr_list)
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unchain_one_elt_list (&v->addr_list);
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pool_free (cselib_val_pool, v);
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}
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/* Remove all entries from the hash table. Also used during
|
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initialization. */
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void
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cselib_clear_table (void)
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{
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cselib_reset_table (1);
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}
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/* Remove from hash table all VALUEs except constants. */
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static int
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preserve_only_constants (void **x, void *info ATTRIBUTE_UNUSED)
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{
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cselib_val *v = (cselib_val *)*x;
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|
|
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if (v->locs != NULL
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&& v->locs->next == NULL)
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{
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if (CONSTANT_P (v->locs->loc)
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&& (GET_CODE (v->locs->loc) != CONST
|
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|| !references_value_p (v->locs->loc, 0)))
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return 1;
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if (cfa_base_preserved_val)
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|||
|
{
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|
if (v == cfa_base_preserved_val)
|
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return 1;
|
|||
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if (GET_CODE (v->locs->loc) == PLUS
|
|||
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&& CONST_INT_P (XEXP (v->locs->loc, 1))
|
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&& XEXP (v->locs->loc, 0) == cfa_base_preserved_val->val_rtx)
|
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return 1;
|
|||
|
}
|
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|
}
|
|||
|
|
|||
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htab_clear_slot (cselib_hash_table, x);
|
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return 1;
|
|||
|
}
|
|||
|
|
|||
|
/* Remove all entries from the hash table, arranging for the next
|
|||
|
value to be numbered NUM. */
|
|||
|
|
|||
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void
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cselib_reset_table (unsigned int num)
|
|||
|
{
|
|||
|
unsigned int i;
|
|||
|
|
|||
|
max_value_regs = 0;
|
|||
|
|
|||
|
if (cfa_base_preserved_val)
|
|||
|
{
|
|||
|
unsigned int regno = REGNO (cfa_base_preserved_val->locs->loc);
|
|||
|
unsigned int new_used_regs = 0;
|
|||
|
for (i = 0; i < n_used_regs; i++)
|
|||
|
if (used_regs[i] == regno)
|
|||
|
{
|
|||
|
new_used_regs = 1;
|
|||
|
continue;
|
|||
|
}
|
|||
|
else
|
|||
|
REG_VALUES (used_regs[i]) = 0;
|
|||
|
gcc_assert (new_used_regs == 1);
|
|||
|
n_used_regs = new_used_regs;
|
|||
|
used_regs[0] = regno;
|
|||
|
max_value_regs
|
|||
|
= hard_regno_nregs[regno][GET_MODE (cfa_base_preserved_val->locs->loc)];
|
|||
|
}
|
|||
|
else
|
|||
|
{
|
|||
|
for (i = 0; i < n_used_regs; i++)
|
|||
|
REG_VALUES (used_regs[i]) = 0;
|
|||
|
n_used_regs = 0;
|
|||
|
}
|
|||
|
|
|||
|
if (cselib_preserve_constants)
|
|||
|
htab_traverse (cselib_hash_table, preserve_only_constants, NULL);
|
|||
|
else
|
|||
|
htab_empty (cselib_hash_table);
|
|||
|
|
|||
|
n_useless_values = 0;
|
|||
|
n_useless_debug_values = 0;
|
|||
|
n_debug_values = 0;
|
|||
|
|
|||
|
next_uid = num;
|
|||
|
|
|||
|
first_containing_mem = &dummy_val;
|
|||
|
}
|
|||
|
|
|||
|
/* Return the number of the next value that will be generated. */
|
|||
|
|
|||
|
unsigned int
|
|||
|
cselib_get_next_uid (void)
|
|||
|
{
|
|||
|
return next_uid;
|
|||
|
}
|
|||
|
|
|||
|
/* The equality test for our hash table. The first argument ENTRY is a table
|
|||
|
element (i.e. a cselib_val), while the second arg X is an rtx. We know
|
|||
|
that all callers of htab_find_slot_with_hash will wrap CONST_INTs into a
|
|||
|
CONST of an appropriate mode. */
|
|||
|
|
|||
|
static int
|
|||
|
entry_and_rtx_equal_p (const void *entry, const void *x_arg)
|
|||
|
{
|
|||
|
struct elt_loc_list *l;
|
|||
|
const cselib_val *const v = (const cselib_val *) entry;
|
|||
|
rtx x = CONST_CAST_RTX ((const_rtx)x_arg);
|
|||
|
enum machine_mode mode = GET_MODE (x);
|
|||
|
|
|||
|
gcc_assert (!CONST_INT_P (x) && GET_CODE (x) != CONST_FIXED
|
|||
|
&& (mode != VOIDmode || GET_CODE (x) != CONST_DOUBLE));
|
|||
|
|
|||
|
if (mode != GET_MODE (v->val_rtx))
|
|||
|
return 0;
|
|||
|
|
|||
|
/* Unwrap X if necessary. */
|
|||
|
if (GET_CODE (x) == CONST
|
|||
|
&& (CONST_INT_P (XEXP (x, 0))
|
|||
|
|| GET_CODE (XEXP (x, 0)) == CONST_FIXED
|
|||
|
|| GET_CODE (XEXP (x, 0)) == CONST_DOUBLE))
|
|||
|
x = XEXP (x, 0);
|
|||
|
|
|||
|
/* We don't guarantee that distinct rtx's have different hash values,
|
|||
|
so we need to do a comparison. */
|
|||
|
for (l = v->locs; l; l = l->next)
|
|||
|
if (rtx_equal_for_cselib_p (l->loc, x))
|
|||
|
{
|
|||
|
promote_debug_loc (l);
|
|||
|
return 1;
|
|||
|
}
|
|||
|
|
|||
|
return 0;
|
|||
|
}
|
|||
|
|
|||
|
/* The hash function for our hash table. The value is always computed with
|
|||
|
cselib_hash_rtx when adding an element; this function just extracts the
|
|||
|
hash value from a cselib_val structure. */
|
|||
|
|
|||
|
static hashval_t
|
|||
|
get_value_hash (const void *entry)
|
|||
|
{
|
|||
|
const cselib_val *const v = (const cselib_val *) entry;
|
|||
|
return v->hash;
|
|||
|
}
|
|||
|
|
|||
|
/* Return true if X contains a VALUE rtx. If ONLY_USELESS is set, we
|
|||
|
only return true for values which point to a cselib_val whose value
|
|||
|
element has been set to zero, which implies the cselib_val will be
|
|||
|
removed. */
|
|||
|
|
|||
|
int
|
|||
|
references_value_p (const_rtx x, int only_useless)
|
|||
|
{
|
|||
|
const enum rtx_code code = GET_CODE (x);
|
|||
|
const char *fmt = GET_RTX_FORMAT (code);
|
|||
|
int i, j;
|
|||
|
|
|||
|
if (GET_CODE (x) == VALUE
|
|||
|
&& (! only_useless || CSELIB_VAL_PTR (x)->locs == 0))
|
|||
|
return 1;
|
|||
|
|
|||
|
for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
|
|||
|
{
|
|||
|
if (fmt[i] == 'e' && references_value_p (XEXP (x, i), only_useless))
|
|||
|
return 1;
|
|||
|
else if (fmt[i] == 'E')
|
|||
|
for (j = 0; j < XVECLEN (x, i); j++)
|
|||
|
if (references_value_p (XVECEXP (x, i, j), only_useless))
|
|||
|
return 1;
|
|||
|
}
|
|||
|
|
|||
|
return 0;
|
|||
|
}
|
|||
|
|
|||
|
/* For all locations found in X, delete locations that reference useless
|
|||
|
values (i.e. values without any location). Called through
|
|||
|
htab_traverse. */
|
|||
|
|
|||
|
static int
|
|||
|
discard_useless_locs (void **x, void *info ATTRIBUTE_UNUSED)
|
|||
|
{
|
|||
|
cselib_val *v = (cselib_val *)*x;
|
|||
|
struct elt_loc_list **p = &v->locs;
|
|||
|
bool had_locs = v->locs != NULL;
|
|||
|
rtx setting_insn = v->locs ? v->locs->setting_insn : NULL;
|
|||
|
|
|||
|
while (*p)
|
|||
|
{
|
|||
|
if (references_value_p ((*p)->loc, 1))
|
|||
|
unchain_one_elt_loc_list (p);
|
|||
|
else
|
|||
|
p = &(*p)->next;
|
|||
|
}
|
|||
|
|
|||
|
if (had_locs && v->locs == 0 && !PRESERVED_VALUE_P (v->val_rtx))
|
|||
|
{
|
|||
|
if (setting_insn && DEBUG_INSN_P (setting_insn))
|
|||
|
n_useless_debug_values++;
|
|||
|
else
|
|||
|
n_useless_values++;
|
|||
|
values_became_useless = 1;
|
|||
|
}
|
|||
|
return 1;
|
|||
|
}
|
|||
|
|
|||
|
/* If X is a value with no locations, remove it from the hashtable. */
|
|||
|
|
|||
|
static int
|
|||
|
discard_useless_values (void **x, void *info ATTRIBUTE_UNUSED)
|
|||
|
{
|
|||
|
cselib_val *v = (cselib_val *)*x;
|
|||
|
|
|||
|
if (v->locs == 0 && !PRESERVED_VALUE_P (v->val_rtx))
|
|||
|
{
|
|||
|
if (cselib_discard_hook)
|
|||
|
cselib_discard_hook (v);
|
|||
|
|
|||
|
CSELIB_VAL_PTR (v->val_rtx) = NULL;
|
|||
|
htab_clear_slot (cselib_hash_table, x);
|
|||
|
unchain_one_value (v);
|
|||
|
n_useless_values--;
|
|||
|
}
|
|||
|
|
|||
|
return 1;
|
|||
|
}
|
|||
|
|
|||
|
/* Clean out useless values (i.e. those which no longer have locations
|
|||
|
associated with them) from the hash table. */
|
|||
|
|
|||
|
static void
|
|||
|
remove_useless_values (void)
|
|||
|
{
|
|||
|
cselib_val **p, *v;
|
|||
|
|
|||
|
/* First pass: eliminate locations that reference the value. That in
|
|||
|
turn can make more values useless. */
|
|||
|
do
|
|||
|
{
|
|||
|
values_became_useless = 0;
|
|||
|
htab_traverse (cselib_hash_table, discard_useless_locs, 0);
|
|||
|
}
|
|||
|
while (values_became_useless);
|
|||
|
|
|||
|
/* Second pass: actually remove the values. */
|
|||
|
|
|||
|
p = &first_containing_mem;
|
|||
|
for (v = *p; v != &dummy_val; v = v->next_containing_mem)
|
|||
|
if (v->locs)
|
|||
|
{
|
|||
|
*p = v;
|
|||
|
p = &(*p)->next_containing_mem;
|
|||
|
}
|
|||
|
*p = &dummy_val;
|
|||
|
|
|||
|
n_useless_values += n_useless_debug_values;
|
|||
|
n_debug_values -= n_useless_debug_values;
|
|||
|
n_useless_debug_values = 0;
|
|||
|
|
|||
|
htab_traverse (cselib_hash_table, discard_useless_values, 0);
|
|||
|
|
|||
|
gcc_assert (!n_useless_values);
|
|||
|
}
|
|||
|
|
|||
|
/* Arrange for a value to not be removed from the hash table even if
|
|||
|
it becomes useless. */
|
|||
|
|
|||
|
void
|
|||
|
cselib_preserve_value (cselib_val *v)
|
|||
|
{
|
|||
|
PRESERVED_VALUE_P (v->val_rtx) = 1;
|
|||
|
}
|
|||
|
|
|||
|
/* Test whether a value is preserved. */
|
|||
|
|
|||
|
bool
|
|||
|
cselib_preserved_value_p (cselib_val *v)
|
|||
|
{
|
|||
|
return PRESERVED_VALUE_P (v->val_rtx);
|
|||
|
}
|
|||
|
|
|||
|
/* Arrange for a REG value to be assumed constant through the whole function,
|
|||
|
never invalidated and preserved across cselib_reset_table calls. */
|
|||
|
|
|||
|
void
|
|||
|
cselib_preserve_cfa_base_value (cselib_val *v)
|
|||
|
{
|
|||
|
if (cselib_preserve_constants
|
|||
|
&& v->locs
|
|||
|
&& REG_P (v->locs->loc))
|
|||
|
cfa_base_preserved_val = v;
|
|||
|
}
|
|||
|
|
|||
|
/* Clean all non-constant expressions in the hash table, but retain
|
|||
|
their values. */
|
|||
|
|
|||
|
void
|
|||
|
cselib_preserve_only_values (void)
|
|||
|
{
|
|||
|
int i;
|
|||
|
|
|||
|
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
|
|||
|
cselib_invalidate_regno (i, reg_raw_mode[i]);
|
|||
|
|
|||
|
cselib_invalidate_mem (callmem);
|
|||
|
|
|||
|
remove_useless_values ();
|
|||
|
|
|||
|
gcc_assert (first_containing_mem == &dummy_val);
|
|||
|
}
|
|||
|
|
|||
|
/* Return the mode in which a register was last set. If X is not a
|
|||
|
register, return its mode. If the mode in which the register was
|
|||
|
set is not known, or the value was already clobbered, return
|
|||
|
VOIDmode. */
|
|||
|
|
|||
|
enum machine_mode
|
|||
|
cselib_reg_set_mode (const_rtx x)
|
|||
|
{
|
|||
|
if (!REG_P (x))
|
|||
|
return GET_MODE (x);
|
|||
|
|
|||
|
if (REG_VALUES (REGNO (x)) == NULL
|
|||
|
|| REG_VALUES (REGNO (x))->elt == NULL)
|
|||
|
return VOIDmode;
|
|||
|
|
|||
|
return GET_MODE (REG_VALUES (REGNO (x))->elt->val_rtx);
|
|||
|
}
|
|||
|
|
|||
|
/* Return nonzero if we can prove that X and Y contain the same value, taking
|
|||
|
our gathered information into account. */
|
|||
|
|
|||
|
int
|
|||
|
rtx_equal_for_cselib_p (rtx x, rtx y)
|
|||
|
{
|
|||
|
enum rtx_code code;
|
|||
|
const char *fmt;
|
|||
|
int i;
|
|||
|
|
|||
|
if (REG_P (x) || MEM_P (x))
|
|||
|
{
|
|||
|
cselib_val *e = cselib_lookup (x, GET_MODE (x), 0);
|
|||
|
|
|||
|
if (e)
|
|||
|
x = e->val_rtx;
|
|||
|
}
|
|||
|
|
|||
|
if (REG_P (y) || MEM_P (y))
|
|||
|
{
|
|||
|
cselib_val *e = cselib_lookup (y, GET_MODE (y), 0);
|
|||
|
|
|||
|
if (e)
|
|||
|
y = e->val_rtx;
|
|||
|
}
|
|||
|
|
|||
|
if (x == y)
|
|||
|
return 1;
|
|||
|
|
|||
|
if (GET_CODE (x) == VALUE && GET_CODE (y) == VALUE)
|
|||
|
return CSELIB_VAL_PTR (x) == CSELIB_VAL_PTR (y);
|
|||
|
|
|||
|
if (GET_CODE (x) == VALUE)
|
|||
|
{
|
|||
|
cselib_val *e = CSELIB_VAL_PTR (x);
|
|||
|
struct elt_loc_list *l;
|
|||
|
|
|||
|
for (l = e->locs; l; l = l->next)
|
|||
|
{
|
|||
|
rtx t = l->loc;
|
|||
|
|
|||
|
/* Avoid infinite recursion. */
|
|||
|
if (REG_P (t) || MEM_P (t))
|
|||
|
continue;
|
|||
|
else if (rtx_equal_for_cselib_p (t, y))
|
|||
|
return 1;
|
|||
|
}
|
|||
|
|
|||
|
return 0;
|
|||
|
}
|
|||
|
|
|||
|
if (GET_CODE (y) == VALUE)
|
|||
|
{
|
|||
|
cselib_val *e = CSELIB_VAL_PTR (y);
|
|||
|
struct elt_loc_list *l;
|
|||
|
|
|||
|
for (l = e->locs; l; l = l->next)
|
|||
|
{
|
|||
|
rtx t = l->loc;
|
|||
|
|
|||
|
if (REG_P (t) || MEM_P (t))
|
|||
|
continue;
|
|||
|
else if (rtx_equal_for_cselib_p (x, t))
|
|||
|
return 1;
|
|||
|
}
|
|||
|
|
|||
|
return 0;
|
|||
|
}
|
|||
|
|
|||
|
if (GET_CODE (x) != GET_CODE (y) || GET_MODE (x) != GET_MODE (y))
|
|||
|
return 0;
|
|||
|
|
|||
|
/* These won't be handled correctly by the code below. */
|
|||
|
switch (GET_CODE (x))
|
|||
|
{
|
|||
|
case CONST_DOUBLE:
|
|||
|
case CONST_FIXED:
|
|||
|
case DEBUG_EXPR:
|
|||
|
return 0;
|
|||
|
|
|||
|
case LABEL_REF:
|
|||
|
return XEXP (x, 0) == XEXP (y, 0);
|
|||
|
|
|||
|
default:
|
|||
|
break;
|
|||
|
}
|
|||
|
|
|||
|
code = GET_CODE (x);
|
|||
|
fmt = GET_RTX_FORMAT (code);
|
|||
|
|
|||
|
for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
|
|||
|
{
|
|||
|
int j;
|
|||
|
|
|||
|
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_cselib_p (XVECEXP (x, i, j),
|
|||
|
XVECEXP (y, i, j)))
|
|||
|
return 0;
|
|||
|
break;
|
|||
|
|
|||
|
case 'e':
|
|||
|
if (i == 1
|
|||
|
&& targetm.commutative_p (x, UNKNOWN)
|
|||
|
&& rtx_equal_for_cselib_p (XEXP (x, 1), XEXP (y, 0))
|
|||
|
&& rtx_equal_for_cselib_p (XEXP (x, 0), XEXP (y, 1)))
|
|||
|
return 1;
|
|||
|
if (! rtx_equal_for_cselib_p (XEXP (x, i), XEXP (y, i)))
|
|||
|
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:
|
|||
|
gcc_unreachable ();
|
|||
|
}
|
|||
|
}
|
|||
|
return 1;
|
|||
|
}
|
|||
|
|
|||
|
/* We need to pass down the mode of constants through the hash table
|
|||
|
functions. For that purpose, wrap them in a CONST of the appropriate
|
|||
|
mode. */
|
|||
|
static rtx
|
|||
|
wrap_constant (enum machine_mode mode, rtx x)
|
|||
|
{
|
|||
|
if (!CONST_INT_P (x) && GET_CODE (x) != CONST_FIXED
|
|||
|
&& (GET_CODE (x) != CONST_DOUBLE || GET_MODE (x) != VOIDmode))
|
|||
|
return x;
|
|||
|
gcc_assert (mode != VOIDmode);
|
|||
|
return gen_rtx_CONST (mode, x);
|
|||
|
}
|
|||
|
|
|||
|
/* Hash an rtx. Return 0 if we couldn't hash the rtx.
|
|||
|
For registers and memory locations, we look up their cselib_val structure
|
|||
|
and return its VALUE element.
|
|||
|
Possible reasons for return 0 are: the object is volatile, or we couldn't
|
|||
|
find a register or memory location in the table and CREATE is zero. If
|
|||
|
CREATE is nonzero, table elts are created for regs and mem.
|
|||
|
N.B. this hash function returns the same hash value for RTXes that
|
|||
|
differ only in the order of operands, thus it is suitable for comparisons
|
|||
|
that take commutativity into account.
|
|||
|
If we wanted to also support associative rules, we'd have to use a different
|
|||
|
strategy to avoid returning spurious 0, e.g. return ~(~0U >> 1) .
|
|||
|
We used to have a MODE argument for hashing for CONST_INTs, but that
|
|||
|
didn't make sense, since it caused spurious hash differences between
|
|||
|
(set (reg:SI 1) (const_int))
|
|||
|
(plus:SI (reg:SI 2) (reg:SI 1))
|
|||
|
and
|
|||
|
(plus:SI (reg:SI 2) (const_int))
|
|||
|
If the mode is important in any context, it must be checked specifically
|
|||
|
in a comparison anyway, since relying on hash differences is unsafe. */
|
|||
|
|
|||
|
static unsigned int
|
|||
|
cselib_hash_rtx (rtx x, int create)
|
|||
|
{
|
|||
|
cselib_val *e;
|
|||
|
int i, j;
|
|||
|
enum rtx_code code;
|
|||
|
const char *fmt;
|
|||
|
unsigned int hash = 0;
|
|||
|
|
|||
|
code = GET_CODE (x);
|
|||
|
hash += (unsigned) code + (unsigned) GET_MODE (x);
|
|||
|
|
|||
|
switch (code)
|
|||
|
{
|
|||
|
case MEM:
|
|||
|
case REG:
|
|||
|
e = cselib_lookup (x, GET_MODE (x), create);
|
|||
|
if (! e)
|
|||
|
return 0;
|
|||
|
|
|||
|
return e->hash;
|
|||
|
|
|||
|
case DEBUG_EXPR:
|
|||
|
hash += ((unsigned) DEBUG_EXPR << 7)
|
|||
|
+ DEBUG_TEMP_UID (DEBUG_EXPR_TREE_DECL (x));
|
|||
|
return hash ? hash : (unsigned int) DEBUG_EXPR;
|
|||
|
|
|||
|
case CONST_INT:
|
|||
|
hash += ((unsigned) CONST_INT << 7) + INTVAL (x);
|
|||
|
return hash ? hash : (unsigned int) CONST_INT;
|
|||
|
|
|||
|
case CONST_DOUBLE:
|
|||
|
/* This is like the general case, except that it only counts
|
|||
|
the integers representing the constant. */
|
|||
|
hash += (unsigned) code + (unsigned) GET_MODE (x);
|
|||
|
if (GET_MODE (x) != VOIDmode)
|
|||
|
hash += real_hash (CONST_DOUBLE_REAL_VALUE (x));
|
|||
|
else
|
|||
|
hash += ((unsigned) CONST_DOUBLE_LOW (x)
|
|||
|
+ (unsigned) CONST_DOUBLE_HIGH (x));
|
|||
|
return hash ? hash : (unsigned int) CONST_DOUBLE;
|
|||
|
|
|||
|
case CONST_FIXED:
|
|||
|
hash += (unsigned int) code + (unsigned int) GET_MODE (x);
|
|||
|
hash += fixed_hash (CONST_FIXED_VALUE (x));
|
|||
|
return hash ? hash : (unsigned int) CONST_FIXED;
|
|||
|
|
|||
|
case CONST_VECTOR:
|
|||
|
{
|
|||
|
int units;
|
|||
|
rtx elt;
|
|||
|
|
|||
|
units = CONST_VECTOR_NUNITS (x);
|
|||
|
|
|||
|
for (i = 0; i < units; ++i)
|
|||
|
{
|
|||
|
elt = CONST_VECTOR_ELT (x, i);
|
|||
|
hash += cselib_hash_rtx (elt, 0);
|
|||
|
}
|
|||
|
|
|||
|
return hash;
|
|||
|
}
|
|||
|
|
|||
|
/* Assume there is only one rtx object for any given label. */
|
|||
|
case LABEL_REF:
|
|||
|
/* We don't hash on the address of the CODE_LABEL to avoid bootstrap
|
|||
|
differences and differences between each stage's debugging dumps. */
|
|||
|
hash += (((unsigned int) LABEL_REF << 7)
|
|||
|
+ CODE_LABEL_NUMBER (XEXP (x, 0)));
|
|||
|
return hash ? hash : (unsigned int) LABEL_REF;
|
|||
|
|
|||
|
case SYMBOL_REF:
|
|||
|
{
|
|||
|
/* Don't hash on the symbol's address to avoid bootstrap differences.
|
|||
|
Different hash values may cause expressions to be recorded in
|
|||
|
different orders and thus different registers to be used in the
|
|||
|
final assembler. This also avoids differences in the dump files
|
|||
|
between various stages. */
|
|||
|
unsigned int h = 0;
|
|||
|
const unsigned char *p = (const unsigned char *) XSTR (x, 0);
|
|||
|
|
|||
|
while (*p)
|
|||
|
h += (h << 7) + *p++; /* ??? revisit */
|
|||
|
|
|||
|
hash += ((unsigned int) SYMBOL_REF << 7) + h;
|
|||
|
return hash ? hash : (unsigned int) SYMBOL_REF;
|
|||
|
}
|
|||
|
|
|||
|
case PRE_DEC:
|
|||
|
case PRE_INC:
|
|||
|
case POST_DEC:
|
|||
|
case POST_INC:
|
|||
|
case POST_MODIFY:
|
|||
|
case PRE_MODIFY:
|
|||
|
case PC:
|
|||
|
case CC0:
|
|||
|
case CALL:
|
|||
|
case UNSPEC_VOLATILE:
|
|||
|
return 0;
|
|||
|
|
|||
|
case ASM_OPERANDS:
|
|||
|
if (MEM_VOLATILE_P (x))
|
|||
|
return 0;
|
|||
|
|
|||
|
break;
|
|||
|
|
|||
|
default:
|
|||
|
break;
|
|||
|
}
|
|||
|
|
|||
|
i = GET_RTX_LENGTH (code) - 1;
|
|||
|
fmt = GET_RTX_FORMAT (code);
|
|||
|
for (; i >= 0; i--)
|
|||
|
{
|
|||
|
switch (fmt[i])
|
|||
|
{
|
|||
|
case 'e':
|
|||
|
{
|
|||
|
rtx tem = XEXP (x, i);
|
|||
|
unsigned int tem_hash = cselib_hash_rtx (tem, create);
|
|||
|
|
|||
|
if (tem_hash == 0)
|
|||
|
return 0;
|
|||
|
|
|||
|
hash += tem_hash;
|
|||
|
}
|
|||
|
break;
|
|||
|
case 'E':
|
|||
|
for (j = 0; j < XVECLEN (x, i); j++)
|
|||
|
{
|
|||
|
unsigned int tem_hash
|
|||
|
= cselib_hash_rtx (XVECEXP (x, i, j), create);
|
|||
|
|
|||
|
if (tem_hash == 0)
|
|||
|
return 0;
|
|||
|
|
|||
|
hash += tem_hash;
|
|||
|
}
|
|||
|
break;
|
|||
|
|
|||
|
case 's':
|
|||
|
{
|
|||
|
const unsigned char *p = (const unsigned char *) XSTR (x, i);
|
|||
|
|
|||
|
if (p)
|
|||
|
while (*p)
|
|||
|
hash += *p++;
|
|||
|
break;
|
|||
|
}
|
|||
|
|
|||
|
case 'i':
|
|||
|
hash += XINT (x, i);
|
|||
|
break;
|
|||
|
|
|||
|
case '0':
|
|||
|
case 't':
|
|||
|
/* unused */
|
|||
|
break;
|
|||
|
|
|||
|
default:
|
|||
|
gcc_unreachable ();
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
return hash ? hash : 1 + (unsigned int) GET_CODE (x);
|
|||
|
}
|
|||
|
|
|||
|
/* Create a new value structure for VALUE and initialize it. The mode of the
|
|||
|
value is MODE. */
|
|||
|
|
|||
|
static inline cselib_val *
|
|||
|
new_cselib_val (unsigned int hash, enum machine_mode mode, rtx x)
|
|||
|
{
|
|||
|
cselib_val *e = (cselib_val *) pool_alloc (cselib_val_pool);
|
|||
|
|
|||
|
gcc_assert (hash);
|
|||
|
gcc_assert (next_uid);
|
|||
|
|
|||
|
e->hash = hash;
|
|||
|
e->uid = next_uid++;
|
|||
|
/* We use an alloc pool to allocate this RTL construct because it
|
|||
|
accounts for about 8% of the overall memory usage. We know
|
|||
|
precisely when we can have VALUE RTXen (when cselib is active)
|
|||
|
so we don't need to put them in garbage collected memory.
|
|||
|
??? Why should a VALUE be an RTX in the first place? */
|
|||
|
e->val_rtx = (rtx) pool_alloc (value_pool);
|
|||
|
memset (e->val_rtx, 0, RTX_HDR_SIZE);
|
|||
|
PUT_CODE (e->val_rtx, VALUE);
|
|||
|
PUT_MODE (e->val_rtx, mode);
|
|||
|
CSELIB_VAL_PTR (e->val_rtx) = e;
|
|||
|
e->addr_list = 0;
|
|||
|
e->locs = 0;
|
|||
|
e->next_containing_mem = 0;
|
|||
|
|
|||
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
|||
|
{
|
|||
|
fprintf (dump_file, "cselib value %u:%u ", e->uid, hash);
|
|||
|
if (flag_dump_noaddr || flag_dump_unnumbered)
|
|||
|
fputs ("# ", dump_file);
|
|||
|
else
|
|||
|
fprintf (dump_file, "%p ", (void*)e);
|
|||
|
print_rtl_single (dump_file, x);
|
|||
|
fputc ('\n', dump_file);
|
|||
|
}
|
|||
|
|
|||
|
return e;
|
|||
|
}
|
|||
|
|
|||
|
/* ADDR_ELT is a value that is used as address. MEM_ELT is the value that
|
|||
|
contains the data at this address. X is a MEM that represents the
|
|||
|
value. Update the two value structures to represent this situation. */
|
|||
|
|
|||
|
static void
|
|||
|
add_mem_for_addr (cselib_val *addr_elt, cselib_val *mem_elt, rtx x)
|
|||
|
{
|
|||
|
struct elt_loc_list *l;
|
|||
|
|
|||
|
/* Avoid duplicates. */
|
|||
|
for (l = mem_elt->locs; l; l = l->next)
|
|||
|
if (MEM_P (l->loc)
|
|||
|
&& CSELIB_VAL_PTR (XEXP (l->loc, 0)) == addr_elt)
|
|||
|
{
|
|||
|
promote_debug_loc (l);
|
|||
|
return;
|
|||
|
}
|
|||
|
|
|||
|
addr_elt->addr_list = new_elt_list (addr_elt->addr_list, mem_elt);
|
|||
|
mem_elt->locs
|
|||
|
= new_elt_loc_list (mem_elt->locs,
|
|||
|
replace_equiv_address_nv (x, addr_elt->val_rtx));
|
|||
|
if (mem_elt->next_containing_mem == NULL)
|
|||
|
{
|
|||
|
mem_elt->next_containing_mem = first_containing_mem;
|
|||
|
first_containing_mem = mem_elt;
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
/* Subroutine of cselib_lookup. Return a value for X, which is a MEM rtx.
|
|||
|
If CREATE, make a new one if we haven't seen it before. */
|
|||
|
|
|||
|
static cselib_val *
|
|||
|
cselib_lookup_mem (rtx x, int create)
|
|||
|
{
|
|||
|
enum machine_mode mode = GET_MODE (x);
|
|||
|
void **slot;
|
|||
|
cselib_val *addr;
|
|||
|
cselib_val *mem_elt;
|
|||
|
struct elt_list *l;
|
|||
|
|
|||
|
if (MEM_VOLATILE_P (x) || mode == BLKmode
|
|||
|
|| !cselib_record_memory
|
|||
|
|| (FLOAT_MODE_P (mode) && flag_float_store))
|
|||
|
return 0;
|
|||
|
|
|||
|
/* Look up the value for the address. */
|
|||
|
addr = cselib_lookup (XEXP (x, 0), mode, create);
|
|||
|
if (! addr)
|
|||
|
return 0;
|
|||
|
|
|||
|
/* Find a value that describes a value of our mode at that address. */
|
|||
|
for (l = addr->addr_list; l; l = l->next)
|
|||
|
if (GET_MODE (l->elt->val_rtx) == mode)
|
|||
|
{
|
|||
|
promote_debug_loc (l->elt->locs);
|
|||
|
return l->elt;
|
|||
|
}
|
|||
|
|
|||
|
if (! create)
|
|||
|
return 0;
|
|||
|
|
|||
|
mem_elt = new_cselib_val (next_uid, mode, x);
|
|||
|
add_mem_for_addr (addr, mem_elt, x);
|
|||
|
slot = htab_find_slot_with_hash (cselib_hash_table, wrap_constant (mode, x),
|
|||
|
mem_elt->hash, INSERT);
|
|||
|
*slot = mem_elt;
|
|||
|
return mem_elt;
|
|||
|
}
|
|||
|
|
|||
|
/* Search thru the possible substitutions in P. We prefer a non reg
|
|||
|
substitution because this allows us to expand the tree further. If
|
|||
|
we find, just a reg, take the lowest regno. There may be several
|
|||
|
non-reg results, we just take the first one because they will all
|
|||
|
expand to the same place. */
|
|||
|
|
|||
|
static rtx
|
|||
|
expand_loc (struct elt_loc_list *p, struct expand_value_data *evd,
|
|||
|
int max_depth)
|
|||
|
{
|
|||
|
rtx reg_result = NULL;
|
|||
|
unsigned int regno = UINT_MAX;
|
|||
|
struct elt_loc_list *p_in = p;
|
|||
|
|
|||
|
for (; p; p = p -> next)
|
|||
|
{
|
|||
|
/* Avoid infinite recursion trying to expand a reg into a
|
|||
|
the same reg. */
|
|||
|
if ((REG_P (p->loc))
|
|||
|
&& (REGNO (p->loc) < regno)
|
|||
|
&& !bitmap_bit_p (evd->regs_active, REGNO (p->loc)))
|
|||
|
{
|
|||
|
reg_result = p->loc;
|
|||
|
regno = REGNO (p->loc);
|
|||
|
}
|
|||
|
/* Avoid infinite recursion and do not try to expand the
|
|||
|
value. */
|
|||
|
else if (GET_CODE (p->loc) == VALUE
|
|||
|
&& CSELIB_VAL_PTR (p->loc)->locs == p_in)
|
|||
|
continue;
|
|||
|
else if (!REG_P (p->loc))
|
|||
|
{
|
|||
|
rtx result, note;
|
|||
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
|||
|
{
|
|||
|
print_inline_rtx (dump_file, p->loc, 0);
|
|||
|
fprintf (dump_file, "\n");
|
|||
|
}
|
|||
|
if (GET_CODE (p->loc) == LO_SUM
|
|||
|
&& GET_CODE (XEXP (p->loc, 1)) == SYMBOL_REF
|
|||
|
&& p->setting_insn
|
|||
|
&& (note = find_reg_note (p->setting_insn, REG_EQUAL, NULL_RTX))
|
|||
|
&& XEXP (note, 0) == XEXP (p->loc, 1))
|
|||
|
return XEXP (p->loc, 1);
|
|||
|
result = cselib_expand_value_rtx_1 (p->loc, evd, max_depth - 1);
|
|||
|
if (result)
|
|||
|
return result;
|
|||
|
}
|
|||
|
|
|||
|
}
|
|||
|
|
|||
|
if (regno != UINT_MAX)
|
|||
|
{
|
|||
|
rtx result;
|
|||
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
|||
|
fprintf (dump_file, "r%d\n", regno);
|
|||
|
|
|||
|
result = cselib_expand_value_rtx_1 (reg_result, evd, max_depth - 1);
|
|||
|
if (result)
|
|||
|
return result;
|
|||
|
}
|
|||
|
|
|||
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
|||
|
{
|
|||
|
if (reg_result)
|
|||
|
{
|
|||
|
print_inline_rtx (dump_file, reg_result, 0);
|
|||
|
fprintf (dump_file, "\n");
|
|||
|
}
|
|||
|
else
|
|||
|
fprintf (dump_file, "NULL\n");
|
|||
|
}
|
|||
|
return reg_result;
|
|||
|
}
|
|||
|
|
|||
|
|
|||
|
/* Forward substitute and expand an expression out to its roots.
|
|||
|
This is the opposite of common subexpression. Because local value
|
|||
|
numbering is such a weak optimization, the expanded expression is
|
|||
|
pretty much unique (not from a pointer equals point of view but
|
|||
|
from a tree shape point of view.
|
|||
|
|
|||
|
This function returns NULL if the expansion fails. The expansion
|
|||
|
will fail if there is no value number for one of the operands or if
|
|||
|
one of the operands has been overwritten between the current insn
|
|||
|
and the beginning of the basic block. For instance x has no
|
|||
|
expansion in:
|
|||
|
|
|||
|
r1 <- r1 + 3
|
|||
|
x <- r1 + 8
|
|||
|
|
|||
|
REGS_ACTIVE is a scratch bitmap that should be clear when passing in.
|
|||
|
It is clear on return. */
|
|||
|
|
|||
|
rtx
|
|||
|
cselib_expand_value_rtx (rtx orig, bitmap regs_active, int max_depth)
|
|||
|
{
|
|||
|
struct expand_value_data evd;
|
|||
|
|
|||
|
evd.regs_active = regs_active;
|
|||
|
evd.callback = NULL;
|
|||
|
evd.callback_arg = NULL;
|
|||
|
evd.dummy = false;
|
|||
|
|
|||
|
return cselib_expand_value_rtx_1 (orig, &evd, max_depth);
|
|||
|
}
|
|||
|
|
|||
|
/* Same as cselib_expand_value_rtx, but using a callback to try to
|
|||
|
resolve some expressions. The CB function should return ORIG if it
|
|||
|
can't or does not want to deal with a certain RTX. Any other
|
|||
|
return value, including NULL, will be used as the expansion for
|
|||
|
VALUE, without any further changes. */
|
|||
|
|
|||
|
rtx
|
|||
|
cselib_expand_value_rtx_cb (rtx orig, bitmap regs_active, int max_depth,
|
|||
|
cselib_expand_callback cb, void *data)
|
|||
|
{
|
|||
|
struct expand_value_data evd;
|
|||
|
|
|||
|
evd.regs_active = regs_active;
|
|||
|
evd.callback = cb;
|
|||
|
evd.callback_arg = data;
|
|||
|
evd.dummy = false;
|
|||
|
|
|||
|
return cselib_expand_value_rtx_1 (orig, &evd, max_depth);
|
|||
|
}
|
|||
|
|
|||
|
/* Similar to cselib_expand_value_rtx_cb, but no rtxs are actually copied
|
|||
|
or simplified. Useful to find out whether cselib_expand_value_rtx_cb
|
|||
|
would return NULL or non-NULL, without allocating new rtx. */
|
|||
|
|
|||
|
bool
|
|||
|
cselib_dummy_expand_value_rtx_cb (rtx orig, bitmap regs_active, int max_depth,
|
|||
|
cselib_expand_callback cb, void *data)
|
|||
|
{
|
|||
|
struct expand_value_data evd;
|
|||
|
|
|||
|
evd.regs_active = regs_active;
|
|||
|
evd.callback = cb;
|
|||
|
evd.callback_arg = data;
|
|||
|
evd.dummy = true;
|
|||
|
|
|||
|
return cselib_expand_value_rtx_1 (orig, &evd, max_depth) != NULL;
|
|||
|
}
|
|||
|
|
|||
|
/* Internal implementation of cselib_expand_value_rtx and
|
|||
|
cselib_expand_value_rtx_cb. */
|
|||
|
|
|||
|
static rtx
|
|||
|
cselib_expand_value_rtx_1 (rtx orig, struct expand_value_data *evd,
|
|||
|
int max_depth)
|
|||
|
{
|
|||
|
rtx copy, scopy;
|
|||
|
int i, j;
|
|||
|
RTX_CODE code;
|
|||
|
const char *format_ptr;
|
|||
|
enum machine_mode mode;
|
|||
|
|
|||
|
code = GET_CODE (orig);
|
|||
|
|
|||
|
/* For the context of dse, if we end up expand into a huge tree, we
|
|||
|
will not have a useful address, so we might as well just give up
|
|||
|
quickly. */
|
|||
|
if (max_depth <= 0)
|
|||
|
return NULL;
|
|||
|
|
|||
|
switch (code)
|
|||
|
{
|
|||
|
case REG:
|
|||
|
{
|
|||
|
struct elt_list *l = REG_VALUES (REGNO (orig));
|
|||
|
|
|||
|
if (l && l->elt == NULL)
|
|||
|
l = l->next;
|
|||
|
for (; l; l = l->next)
|
|||
|
if (GET_MODE (l->elt->val_rtx) == GET_MODE (orig))
|
|||
|
{
|
|||
|
rtx result;
|
|||
|
int regno = REGNO (orig);
|
|||
|
|
|||
|
/* The only thing that we are not willing to do (this
|
|||
|
is requirement of dse and if others potential uses
|
|||
|
need this function we should add a parm to control
|
|||
|
it) is that we will not substitute the
|
|||
|
STACK_POINTER_REGNUM, FRAME_POINTER or the
|
|||
|
HARD_FRAME_POINTER.
|
|||
|
|
|||
|
These expansions confuses the code that notices that
|
|||
|
stores into the frame go dead at the end of the
|
|||
|
function and that the frame is not effected by calls
|
|||
|
to subroutines. If you allow the
|
|||
|
STACK_POINTER_REGNUM substitution, then dse will
|
|||
|
think that parameter pushing also goes dead which is
|
|||
|
wrong. If you allow the FRAME_POINTER or the
|
|||
|
HARD_FRAME_POINTER then you lose the opportunity to
|
|||
|
make the frame assumptions. */
|
|||
|
if (regno == STACK_POINTER_REGNUM
|
|||
|
|| regno == FRAME_POINTER_REGNUM
|
|||
|
|| regno == HARD_FRAME_POINTER_REGNUM)
|
|||
|
return orig;
|
|||
|
|
|||
|
bitmap_set_bit (evd->regs_active, regno);
|
|||
|
|
|||
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
|||
|
fprintf (dump_file, "expanding: r%d into: ", regno);
|
|||
|
|
|||
|
result = expand_loc (l->elt->locs, evd, max_depth);
|
|||
|
bitmap_clear_bit (evd->regs_active, regno);
|
|||
|
|
|||
|
if (result)
|
|||
|
return result;
|
|||
|
else
|
|||
|
return orig;
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
case CONST_INT:
|
|||
|
case CONST_DOUBLE:
|
|||
|
case CONST_VECTOR:
|
|||
|
case SYMBOL_REF:
|
|||
|
case CODE_LABEL:
|
|||
|
case PC:
|
|||
|
case CC0:
|
|||
|
case SCRATCH:
|
|||
|
/* SCRATCH must be shared because they represent distinct values. */
|
|||
|
return orig;
|
|||
|
case CLOBBER:
|
|||
|
if (REG_P (XEXP (orig, 0)) && HARD_REGISTER_NUM_P (REGNO (XEXP (orig, 0))))
|
|||
|
return orig;
|
|||
|
break;
|
|||
|
|
|||
|
case CONST:
|
|||
|
if (shared_const_p (orig))
|
|||
|
return orig;
|
|||
|
break;
|
|||
|
|
|||
|
case SUBREG:
|
|||
|
{
|
|||
|
rtx subreg;
|
|||
|
|
|||
|
if (evd->callback)
|
|||
|
{
|
|||
|
subreg = evd->callback (orig, evd->regs_active, max_depth,
|
|||
|
evd->callback_arg);
|
|||
|
if (subreg != orig)
|
|||
|
return subreg;
|
|||
|
}
|
|||
|
|
|||
|
subreg = cselib_expand_value_rtx_1 (SUBREG_REG (orig), evd,
|
|||
|
max_depth - 1);
|
|||
|
if (!subreg)
|
|||
|
return NULL;
|
|||
|
scopy = simplify_gen_subreg (GET_MODE (orig), subreg,
|
|||
|
GET_MODE (SUBREG_REG (orig)),
|
|||
|
SUBREG_BYTE (orig));
|
|||
|
if (scopy == NULL
|
|||
|
|| (GET_CODE (scopy) == SUBREG
|
|||
|
&& !REG_P (SUBREG_REG (scopy))
|
|||
|
&& !MEM_P (SUBREG_REG (scopy))))
|
|||
|
return NULL;
|
|||
|
|
|||
|
return scopy;
|
|||
|
}
|
|||
|
|
|||
|
case VALUE:
|
|||
|
{
|
|||
|
rtx result;
|
|||
|
|
|||
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
|||
|
{
|
|||
|
fputs ("\nexpanding ", dump_file);
|
|||
|
print_rtl_single (dump_file, orig);
|
|||
|
fputs (" into...", dump_file);
|
|||
|
}
|
|||
|
|
|||
|
if (evd->callback)
|
|||
|
{
|
|||
|
result = evd->callback (orig, evd->regs_active, max_depth,
|
|||
|
evd->callback_arg);
|
|||
|
|
|||
|
if (result != orig)
|
|||
|
return result;
|
|||
|
}
|
|||
|
|
|||
|
result = expand_loc (CSELIB_VAL_PTR (orig)->locs, evd, max_depth);
|
|||
|
return result;
|
|||
|
}
|
|||
|
|
|||
|
case DEBUG_EXPR:
|
|||
|
if (evd->callback)
|
|||
|
return evd->callback (orig, evd->regs_active, max_depth,
|
|||
|
evd->callback_arg);
|
|||
|
return orig;
|
|||
|
|
|||
|
default:
|
|||
|
break;
|
|||
|
}
|
|||
|
|
|||
|
/* Copy the various flags, fields, and other information. We assume
|
|||
|
that all fields need copying, and then clear the fields that should
|
|||
|
not be copied. That is the sensible default behavior, and forces
|
|||
|
us to explicitly document why we are *not* copying a flag. */
|
|||
|
if (evd->dummy)
|
|||
|
copy = NULL;
|
|||
|
else
|
|||
|
copy = shallow_copy_rtx (orig);
|
|||
|
|
|||
|
format_ptr = GET_RTX_FORMAT (code);
|
|||
|
|
|||
|
for (i = 0; i < GET_RTX_LENGTH (code); i++)
|
|||
|
switch (*format_ptr++)
|
|||
|
{
|
|||
|
case 'e':
|
|||
|
if (XEXP (orig, i) != NULL)
|
|||
|
{
|
|||
|
rtx result = cselib_expand_value_rtx_1 (XEXP (orig, i), evd,
|
|||
|
max_depth - 1);
|
|||
|
if (!result)
|
|||
|
return NULL;
|
|||
|
if (copy)
|
|||
|
XEXP (copy, i) = result;
|
|||
|
}
|
|||
|
break;
|
|||
|
|
|||
|
case 'E':
|
|||
|
case 'V':
|
|||
|
if (XVEC (orig, i) != NULL)
|
|||
|
{
|
|||
|
if (copy)
|
|||
|
XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i));
|
|||
|
for (j = 0; j < XVECLEN (orig, i); j++)
|
|||
|
{
|
|||
|
rtx result = cselib_expand_value_rtx_1 (XVECEXP (orig, i, j),
|
|||
|
evd, max_depth - 1);
|
|||
|
if (!result)
|
|||
|
return NULL;
|
|||
|
if (copy)
|
|||
|
XVECEXP (copy, i, j) = result;
|
|||
|
}
|
|||
|
}
|
|||
|
break;
|
|||
|
|
|||
|
case 't':
|
|||
|
case 'w':
|
|||
|
case 'i':
|
|||
|
case 's':
|
|||
|
case 'S':
|
|||
|
case 'T':
|
|||
|
case 'u':
|
|||
|
case 'B':
|
|||
|
case '0':
|
|||
|
/* These are left unchanged. */
|
|||
|
break;
|
|||
|
|
|||
|
default:
|
|||
|
gcc_unreachable ();
|
|||
|
}
|
|||
|
|
|||
|
if (evd->dummy)
|
|||
|
return orig;
|
|||
|
|
|||
|
mode = GET_MODE (copy);
|
|||
|
/* If an operand has been simplified into CONST_INT, which doesn't
|
|||
|
have a mode and the mode isn't derivable from whole rtx's mode,
|
|||
|
try simplify_*_operation first with mode from original's operand
|
|||
|
and as a fallback wrap CONST_INT into gen_rtx_CONST. */
|
|||
|
scopy = copy;
|
|||
|
switch (GET_RTX_CLASS (code))
|
|||
|
{
|
|||
|
case RTX_UNARY:
|
|||
|
if (CONST_INT_P (XEXP (copy, 0))
|
|||
|
&& GET_MODE (XEXP (orig, 0)) != VOIDmode)
|
|||
|
{
|
|||
|
scopy = simplify_unary_operation (code, mode, XEXP (copy, 0),
|
|||
|
GET_MODE (XEXP (orig, 0)));
|
|||
|
if (scopy)
|
|||
|
return scopy;
|
|||
|
}
|
|||
|
break;
|
|||
|
case RTX_COMM_ARITH:
|
|||
|
case RTX_BIN_ARITH:
|
|||
|
/* These expressions can derive operand modes from the whole rtx's mode. */
|
|||
|
break;
|
|||
|
case RTX_TERNARY:
|
|||
|
case RTX_BITFIELD_OPS:
|
|||
|
if (CONST_INT_P (XEXP (copy, 0))
|
|||
|
&& GET_MODE (XEXP (orig, 0)) != VOIDmode)
|
|||
|
{
|
|||
|
scopy = simplify_ternary_operation (code, mode,
|
|||
|
GET_MODE (XEXP (orig, 0)),
|
|||
|
XEXP (copy, 0), XEXP (copy, 1),
|
|||
|
XEXP (copy, 2));
|
|||
|
if (scopy)
|
|||
|
return scopy;
|
|||
|
}
|
|||
|
break;
|
|||
|
case RTX_COMPARE:
|
|||
|
case RTX_COMM_COMPARE:
|
|||
|
if (CONST_INT_P (XEXP (copy, 0))
|
|||
|
&& GET_MODE (XEXP (copy, 1)) == VOIDmode
|
|||
|
&& (GET_MODE (XEXP (orig, 0)) != VOIDmode
|
|||
|
|| GET_MODE (XEXP (orig, 1)) != VOIDmode))
|
|||
|
{
|
|||
|
scopy = simplify_relational_operation (code, mode,
|
|||
|
(GET_MODE (XEXP (orig, 0))
|
|||
|
!= VOIDmode)
|
|||
|
? GET_MODE (XEXP (orig, 0))
|
|||
|
: GET_MODE (XEXP (orig, 1)),
|
|||
|
XEXP (copy, 0),
|
|||
|
XEXP (copy, 1));
|
|||
|
if (scopy)
|
|||
|
return scopy;
|
|||
|
}
|
|||
|
break;
|
|||
|
default:
|
|||
|
break;
|
|||
|
}
|
|||
|
scopy = simplify_rtx (copy);
|
|||
|
if (scopy)
|
|||
|
return scopy;
|
|||
|
return copy;
|
|||
|
}
|
|||
|
|
|||
|
/* Walk rtx X and replace all occurrences of REG and MEM subexpressions
|
|||
|
with VALUE expressions. This way, it becomes independent of changes
|
|||
|
to registers and memory.
|
|||
|
X isn't actually modified; if modifications are needed, new rtl is
|
|||
|
allocated. However, the return value can share rtl with X. */
|
|||
|
|
|||
|
rtx
|
|||
|
cselib_subst_to_values (rtx x)
|
|||
|
{
|
|||
|
enum rtx_code code = GET_CODE (x);
|
|||
|
const char *fmt = GET_RTX_FORMAT (code);
|
|||
|
cselib_val *e;
|
|||
|
struct elt_list *l;
|
|||
|
rtx copy = x;
|
|||
|
int i;
|
|||
|
|
|||
|
switch (code)
|
|||
|
{
|
|||
|
case REG:
|
|||
|
l = REG_VALUES (REGNO (x));
|
|||
|
if (l && l->elt == NULL)
|
|||
|
l = l->next;
|
|||
|
for (; l; l = l->next)
|
|||
|
if (GET_MODE (l->elt->val_rtx) == GET_MODE (x))
|
|||
|
return l->elt->val_rtx;
|
|||
|
|
|||
|
gcc_unreachable ();
|
|||
|
|
|||
|
case MEM:
|
|||
|
e = cselib_lookup_mem (x, 0);
|
|||
|
if (! e)
|
|||
|
{
|
|||
|
/* This happens for autoincrements. Assign a value that doesn't
|
|||
|
match any other. */
|
|||
|
e = new_cselib_val (next_uid, GET_MODE (x), x);
|
|||
|
}
|
|||
|
return e->val_rtx;
|
|||
|
|
|||
|
case CONST_DOUBLE:
|
|||
|
case CONST_VECTOR:
|
|||
|
case CONST_INT:
|
|||
|
case CONST_FIXED:
|
|||
|
return x;
|
|||
|
|
|||
|
case POST_INC:
|
|||
|
case PRE_INC:
|
|||
|
case POST_DEC:
|
|||
|
case PRE_DEC:
|
|||
|
case POST_MODIFY:
|
|||
|
case PRE_MODIFY:
|
|||
|
e = new_cselib_val (next_uid, GET_MODE (x), x);
|
|||
|
return e->val_rtx;
|
|||
|
|
|||
|
default:
|
|||
|
break;
|
|||
|
}
|
|||
|
|
|||
|
for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
|
|||
|
{
|
|||
|
if (fmt[i] == 'e')
|
|||
|
{
|
|||
|
rtx t = cselib_subst_to_values (XEXP (x, i));
|
|||
|
|
|||
|
if (t != XEXP (x, i))
|
|||
|
{
|
|||
|
if (x == copy)
|
|||
|
copy = shallow_copy_rtx (x);
|
|||
|
XEXP (copy, i) = t;
|
|||
|
}
|
|||
|
}
|
|||
|
else if (fmt[i] == 'E')
|
|||
|
{
|
|||
|
int j;
|
|||
|
|
|||
|
for (j = 0; j < XVECLEN (x, i); j++)
|
|||
|
{
|
|||
|
rtx t = cselib_subst_to_values (XVECEXP (x, i, j));
|
|||
|
|
|||
|
if (t != XVECEXP (x, i, j))
|
|||
|
{
|
|||
|
if (XVEC (x, i) == XVEC (copy, i))
|
|||
|
{
|
|||
|
if (x == copy)
|
|||
|
copy = shallow_copy_rtx (x);
|
|||
|
XVEC (copy, i) = shallow_copy_rtvec (XVEC (x, i));
|
|||
|
}
|
|||
|
XVECEXP (copy, i, j) = t;
|
|||
|
}
|
|||
|
}
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
return copy;
|
|||
|
}
|
|||
|
|
|||
|
/* Look up the rtl expression X in our tables and return the value it has.
|
|||
|
If CREATE is zero, we return NULL if we don't know the value. Otherwise,
|
|||
|
we create a new one if possible, using mode MODE if X doesn't have a mode
|
|||
|
(i.e. because it's a constant). */
|
|||
|
|
|||
|
static cselib_val *
|
|||
|
cselib_lookup_1 (rtx x, enum machine_mode mode, int create)
|
|||
|
{
|
|||
|
void **slot;
|
|||
|
cselib_val *e;
|
|||
|
unsigned int hashval;
|
|||
|
|
|||
|
if (GET_MODE (x) != VOIDmode)
|
|||
|
mode = GET_MODE (x);
|
|||
|
|
|||
|
if (GET_CODE (x) == VALUE)
|
|||
|
return CSELIB_VAL_PTR (x);
|
|||
|
|
|||
|
if (REG_P (x))
|
|||
|
{
|
|||
|
struct elt_list *l;
|
|||
|
unsigned int i = REGNO (x);
|
|||
|
|
|||
|
l = REG_VALUES (i);
|
|||
|
if (l && l->elt == NULL)
|
|||
|
l = l->next;
|
|||
|
for (; l; l = l->next)
|
|||
|
if (mode == GET_MODE (l->elt->val_rtx))
|
|||
|
{
|
|||
|
promote_debug_loc (l->elt->locs);
|
|||
|
return l->elt;
|
|||
|
}
|
|||
|
|
|||
|
if (! create)
|
|||
|
return 0;
|
|||
|
|
|||
|
if (i < FIRST_PSEUDO_REGISTER)
|
|||
|
{
|
|||
|
unsigned int n = hard_regno_nregs[i][mode];
|
|||
|
|
|||
|
if (n > max_value_regs)
|
|||
|
max_value_regs = n;
|
|||
|
}
|
|||
|
|
|||
|
e = new_cselib_val (next_uid, GET_MODE (x), x);
|
|||
|
e->locs = new_elt_loc_list (e->locs, x);
|
|||
|
if (REG_VALUES (i) == 0)
|
|||
|
{
|
|||
|
/* Maintain the invariant that the first entry of
|
|||
|
REG_VALUES, if present, must be the value used to set the
|
|||
|
register, or NULL. */
|
|||
|
used_regs[n_used_regs++] = i;
|
|||
|
REG_VALUES (i) = new_elt_list (REG_VALUES (i), NULL);
|
|||
|
}
|
|||
|
REG_VALUES (i)->next = new_elt_list (REG_VALUES (i)->next, e);
|
|||
|
slot = htab_find_slot_with_hash (cselib_hash_table, x, e->hash, INSERT);
|
|||
|
*slot = e;
|
|||
|
return e;
|
|||
|
}
|
|||
|
|
|||
|
if (MEM_P (x))
|
|||
|
return cselib_lookup_mem (x, create);
|
|||
|
|
|||
|
hashval = cselib_hash_rtx (x, create);
|
|||
|
/* Can't even create if hashing is not possible. */
|
|||
|
if (! hashval)
|
|||
|
return 0;
|
|||
|
|
|||
|
slot = htab_find_slot_with_hash (cselib_hash_table, wrap_constant (mode, x),
|
|||
|
hashval, create ? INSERT : NO_INSERT);
|
|||
|
if (slot == 0)
|
|||
|
return 0;
|
|||
|
|
|||
|
e = (cselib_val *) *slot;
|
|||
|
if (e)
|
|||
|
return e;
|
|||
|
|
|||
|
e = new_cselib_val (hashval, mode, x);
|
|||
|
|
|||
|
/* We have to fill the slot before calling cselib_subst_to_values:
|
|||
|
the hash table is inconsistent until we do so, and
|
|||
|
cselib_subst_to_values will need to do lookups. */
|
|||
|
*slot = (void *) e;
|
|||
|
e->locs = new_elt_loc_list (e->locs, cselib_subst_to_values (x));
|
|||
|
return e;
|
|||
|
}
|
|||
|
|
|||
|
/* Wrapper for cselib_lookup, that indicates X is in INSN. */
|
|||
|
|
|||
|
cselib_val *
|
|||
|
cselib_lookup_from_insn (rtx x, enum machine_mode mode,
|
|||
|
int create, rtx insn)
|
|||
|
{
|
|||
|
cselib_val *ret;
|
|||
|
|
|||
|
gcc_assert (!cselib_current_insn);
|
|||
|
cselib_current_insn = insn;
|
|||
|
|
|||
|
ret = cselib_lookup (x, mode, create);
|
|||
|
|
|||
|
cselib_current_insn = NULL;
|
|||
|
|
|||
|
return ret;
|
|||
|
}
|
|||
|
|
|||
|
/* Wrapper for cselib_lookup_1, that logs the lookup result and
|
|||
|
maintains invariants related with debug insns. */
|
|||
|
|
|||
|
cselib_val *
|
|||
|
cselib_lookup (rtx x, enum machine_mode mode, int create)
|
|||
|
{
|
|||
|
cselib_val *ret = cselib_lookup_1 (x, mode, create);
|
|||
|
|
|||
|
/* ??? Should we return NULL if we're not to create an entry, the
|
|||
|
found loc is a debug loc and cselib_current_insn is not DEBUG?
|
|||
|
If so, we should also avoid converting val to non-DEBUG; probably
|
|||
|
easiest setting cselib_current_insn to NULL before the call
|
|||
|
above. */
|
|||
|
|
|||
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
|||
|
{
|
|||
|
fputs ("cselib lookup ", dump_file);
|
|||
|
print_inline_rtx (dump_file, x, 2);
|
|||
|
fprintf (dump_file, " => %u:%u\n",
|
|||
|
ret ? ret->uid : 0,
|
|||
|
ret ? ret->hash : 0);
|
|||
|
}
|
|||
|
|
|||
|
return ret;
|
|||
|
}
|
|||
|
|
|||
|
/* Invalidate any entries in reg_values that overlap REGNO. This is called
|
|||
|
if REGNO is changing. MODE is the mode of the assignment to REGNO, which
|
|||
|
is used to determine how many hard registers are being changed. If MODE
|
|||
|
is VOIDmode, then only REGNO is being changed; this is used when
|
|||
|
invalidating call clobbered registers across a call. */
|
|||
|
|
|||
|
static void
|
|||
|
cselib_invalidate_regno (unsigned int regno, enum machine_mode mode)
|
|||
|
{
|
|||
|
unsigned int endregno;
|
|||
|
unsigned int i;
|
|||
|
|
|||
|
/* If we see pseudos after reload, something is _wrong_. */
|
|||
|
gcc_assert (!reload_completed || regno < FIRST_PSEUDO_REGISTER
|
|||
|
|| reg_renumber[regno] < 0);
|
|||
|
|
|||
|
/* Determine the range of registers that must be invalidated. For
|
|||
|
pseudos, only REGNO is affected. For hard regs, we must take MODE
|
|||
|
into account, and we must also invalidate lower register numbers
|
|||
|
if they contain values that overlap REGNO. */
|
|||
|
if (regno < FIRST_PSEUDO_REGISTER)
|
|||
|
{
|
|||
|
gcc_assert (mode != VOIDmode);
|
|||
|
|
|||
|
if (regno < max_value_regs)
|
|||
|
i = 0;
|
|||
|
else
|
|||
|
i = regno - max_value_regs;
|
|||
|
|
|||
|
endregno = end_hard_regno (mode, regno);
|
|||
|
}
|
|||
|
else
|
|||
|
{
|
|||
|
i = regno;
|
|||
|
endregno = regno + 1;
|
|||
|
}
|
|||
|
|
|||
|
for (; i < endregno; i++)
|
|||
|
{
|
|||
|
struct elt_list **l = ®_VALUES (i);
|
|||
|
|
|||
|
/* Go through all known values for this reg; if it overlaps the range
|
|||
|
we're invalidating, remove the value. */
|
|||
|
while (*l)
|
|||
|
{
|
|||
|
cselib_val *v = (*l)->elt;
|
|||
|
bool had_locs;
|
|||
|
rtx setting_insn;
|
|||
|
struct elt_loc_list **p;
|
|||
|
unsigned int this_last = i;
|
|||
|
|
|||
|
if (i < FIRST_PSEUDO_REGISTER && v != NULL)
|
|||
|
this_last = end_hard_regno (GET_MODE (v->val_rtx), i) - 1;
|
|||
|
|
|||
|
if (this_last < regno || v == NULL || v == cfa_base_preserved_val)
|
|||
|
{
|
|||
|
l = &(*l)->next;
|
|||
|
continue;
|
|||
|
}
|
|||
|
|
|||
|
/* We have an overlap. */
|
|||
|
if (*l == REG_VALUES (i))
|
|||
|
{
|
|||
|
/* Maintain the invariant that the first entry of
|
|||
|
REG_VALUES, if present, must be the value used to set
|
|||
|
the register, or NULL. This is also nice because
|
|||
|
then we won't push the same regno onto user_regs
|
|||
|
multiple times. */
|
|||
|
(*l)->elt = NULL;
|
|||
|
l = &(*l)->next;
|
|||
|
}
|
|||
|
else
|
|||
|
unchain_one_elt_list (l);
|
|||
|
|
|||
|
had_locs = v->locs != NULL;
|
|||
|
setting_insn = v->locs ? v->locs->setting_insn : NULL;
|
|||
|
|
|||
|
/* Now, we clear the mapping from value to reg. It must exist, so
|
|||
|
this code will crash intentionally if it doesn't. */
|
|||
|
for (p = &v->locs; ; p = &(*p)->next)
|
|||
|
{
|
|||
|
rtx x = (*p)->loc;
|
|||
|
|
|||
|
if (REG_P (x) && REGNO (x) == i)
|
|||
|
{
|
|||
|
unchain_one_elt_loc_list (p);
|
|||
|
break;
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
if (had_locs && v->locs == 0 && !PRESERVED_VALUE_P (v->val_rtx))
|
|||
|
{
|
|||
|
if (setting_insn && DEBUG_INSN_P (setting_insn))
|
|||
|
n_useless_debug_values++;
|
|||
|
else
|
|||
|
n_useless_values++;
|
|||
|
}
|
|||
|
}
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
/* Return 1 if X has a value that can vary even between two
|
|||
|
executions of the program. 0 means X can be compared reliably
|
|||
|
against certain constants or near-constants. */
|
|||
|
|
|||
|
static bool
|
|||
|
cselib_rtx_varies_p (const_rtx x ATTRIBUTE_UNUSED, bool from_alias ATTRIBUTE_UNUSED)
|
|||
|
{
|
|||
|
/* We actually don't need to verify very hard. This is because
|
|||
|
if X has actually changed, we invalidate the memory anyway,
|
|||
|
so assume that all common memory addresses are
|
|||
|
invariant. */
|
|||
|
return 0;
|
|||
|
}
|
|||
|
|
|||
|
/* Invalidate any locations in the table which are changed because of a
|
|||
|
store to MEM_RTX. If this is called because of a non-const call
|
|||
|
instruction, MEM_RTX is (mem:BLK const0_rtx). */
|
|||
|
|
|||
|
static void
|
|||
|
cselib_invalidate_mem (rtx mem_rtx)
|
|||
|
{
|
|||
|
cselib_val **vp, *v, *next;
|
|||
|
int num_mems = 0;
|
|||
|
rtx mem_addr;
|
|||
|
|
|||
|
mem_addr = canon_rtx (get_addr (XEXP (mem_rtx, 0)));
|
|||
|
mem_rtx = canon_rtx (mem_rtx);
|
|||
|
|
|||
|
vp = &first_containing_mem;
|
|||
|
for (v = *vp; v != &dummy_val; v = next)
|
|||
|
{
|
|||
|
bool has_mem = false;
|
|||
|
struct elt_loc_list **p = &v->locs;
|
|||
|
bool had_locs = v->locs != NULL;
|
|||
|
rtx setting_insn = v->locs ? v->locs->setting_insn : NULL;
|
|||
|
|
|||
|
while (*p)
|
|||
|
{
|
|||
|
rtx x = (*p)->loc;
|
|||
|
cselib_val *addr;
|
|||
|
struct elt_list **mem_chain;
|
|||
|
|
|||
|
/* MEMs may occur in locations only at the top level; below
|
|||
|
that every MEM or REG is substituted by its VALUE. */
|
|||
|
if (!MEM_P (x))
|
|||
|
{
|
|||
|
p = &(*p)->next;
|
|||
|
continue;
|
|||
|
}
|
|||
|
if (num_mems < PARAM_VALUE (PARAM_MAX_CSELIB_MEMORY_LOCATIONS)
|
|||
|
&& ! canon_true_dependence (mem_rtx, GET_MODE (mem_rtx), mem_addr,
|
|||
|
x, NULL_RTX, cselib_rtx_varies_p))
|
|||
|
{
|
|||
|
has_mem = true;
|
|||
|
num_mems++;
|
|||
|
p = &(*p)->next;
|
|||
|
continue;
|
|||
|
}
|
|||
|
|
|||
|
/* This one overlaps. */
|
|||
|
/* We must have a mapping from this MEM's address to the
|
|||
|
value (E). Remove that, too. */
|
|||
|
addr = cselib_lookup (XEXP (x, 0), VOIDmode, 0);
|
|||
|
mem_chain = &addr->addr_list;
|
|||
|
for (;;)
|
|||
|
{
|
|||
|
if ((*mem_chain)->elt == v)
|
|||
|
{
|
|||
|
unchain_one_elt_list (mem_chain);
|
|||
|
break;
|
|||
|
}
|
|||
|
|
|||
|
mem_chain = &(*mem_chain)->next;
|
|||
|
}
|
|||
|
|
|||
|
unchain_one_elt_loc_list (p);
|
|||
|
}
|
|||
|
|
|||
|
if (had_locs && v->locs == 0 && !PRESERVED_VALUE_P (v->val_rtx))
|
|||
|
{
|
|||
|
if (setting_insn && DEBUG_INSN_P (setting_insn))
|
|||
|
n_useless_debug_values++;
|
|||
|
else
|
|||
|
n_useless_values++;
|
|||
|
}
|
|||
|
|
|||
|
next = v->next_containing_mem;
|
|||
|
if (has_mem)
|
|||
|
{
|
|||
|
*vp = v;
|
|||
|
vp = &(*vp)->next_containing_mem;
|
|||
|
}
|
|||
|
else
|
|||
|
v->next_containing_mem = NULL;
|
|||
|
}
|
|||
|
*vp = &dummy_val;
|
|||
|
}
|
|||
|
|
|||
|
/* Invalidate DEST, which is being assigned to or clobbered. */
|
|||
|
|
|||
|
void
|
|||
|
cselib_invalidate_rtx (rtx dest)
|
|||
|
{
|
|||
|
while (GET_CODE (dest) == SUBREG
|
|||
|
|| GET_CODE (dest) == ZERO_EXTRACT
|
|||
|
|| GET_CODE (dest) == STRICT_LOW_PART)
|
|||
|
dest = XEXP (dest, 0);
|
|||
|
|
|||
|
if (REG_P (dest))
|
|||
|
cselib_invalidate_regno (REGNO (dest), GET_MODE (dest));
|
|||
|
else if (MEM_P (dest))
|
|||
|
cselib_invalidate_mem (dest);
|
|||
|
|
|||
|
/* Some machines don't define AUTO_INC_DEC, but they still use push
|
|||
|
instructions. We need to catch that case here in order to
|
|||
|
invalidate the stack pointer correctly. Note that invalidating
|
|||
|
the stack pointer is different from invalidating DEST. */
|
|||
|
if (push_operand (dest, GET_MODE (dest)))
|
|||
|
cselib_invalidate_rtx (stack_pointer_rtx);
|
|||
|
}
|
|||
|
|
|||
|
/* A wrapper for cselib_invalidate_rtx to be called via note_stores. */
|
|||
|
|
|||
|
static void
|
|||
|
cselib_invalidate_rtx_note_stores (rtx dest, const_rtx ignore ATTRIBUTE_UNUSED,
|
|||
|
void *data ATTRIBUTE_UNUSED)
|
|||
|
{
|
|||
|
cselib_invalidate_rtx (dest);
|
|||
|
}
|
|||
|
|
|||
|
/* Record the result of a SET instruction. DEST is being set; the source
|
|||
|
contains the value described by SRC_ELT. If DEST is a MEM, DEST_ADDR_ELT
|
|||
|
describes its address. */
|
|||
|
|
|||
|
static void
|
|||
|
cselib_record_set (rtx dest, cselib_val *src_elt, cselib_val *dest_addr_elt)
|
|||
|
{
|
|||
|
int dreg = REG_P (dest) ? (int) REGNO (dest) : -1;
|
|||
|
|
|||
|
if (src_elt == 0 || side_effects_p (dest))
|
|||
|
return;
|
|||
|
|
|||
|
if (dreg >= 0)
|
|||
|
{
|
|||
|
if (dreg < FIRST_PSEUDO_REGISTER)
|
|||
|
{
|
|||
|
unsigned int n = hard_regno_nregs[dreg][GET_MODE (dest)];
|
|||
|
|
|||
|
if (n > max_value_regs)
|
|||
|
max_value_regs = n;
|
|||
|
}
|
|||
|
|
|||
|
if (REG_VALUES (dreg) == 0)
|
|||
|
{
|
|||
|
used_regs[n_used_regs++] = dreg;
|
|||
|
REG_VALUES (dreg) = new_elt_list (REG_VALUES (dreg), src_elt);
|
|||
|
}
|
|||
|
else
|
|||
|
{
|
|||
|
/* The register should have been invalidated. */
|
|||
|
gcc_assert (REG_VALUES (dreg)->elt == 0);
|
|||
|
REG_VALUES (dreg)->elt = src_elt;
|
|||
|
}
|
|||
|
|
|||
|
if (src_elt->locs == 0 && !PRESERVED_VALUE_P (src_elt->val_rtx))
|
|||
|
n_useless_values--;
|
|||
|
src_elt->locs = new_elt_loc_list (src_elt->locs, dest);
|
|||
|
}
|
|||
|
else if (MEM_P (dest) && dest_addr_elt != 0
|
|||
|
&& cselib_record_memory)
|
|||
|
{
|
|||
|
if (src_elt->locs == 0 && !PRESERVED_VALUE_P (src_elt->val_rtx))
|
|||
|
n_useless_values--;
|
|||
|
add_mem_for_addr (dest_addr_elt, src_elt, dest);
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
/* There is no good way to determine how many elements there can be
|
|||
|
in a PARALLEL. Since it's fairly cheap, use a really large number. */
|
|||
|
#define MAX_SETS (FIRST_PSEUDO_REGISTER * 2)
|
|||
|
|
|||
|
/* Record the effects of any sets in INSN. */
|
|||
|
static void
|
|||
|
cselib_record_sets (rtx insn)
|
|||
|
{
|
|||
|
int n_sets = 0;
|
|||
|
int i;
|
|||
|
struct cselib_set sets[MAX_SETS];
|
|||
|
rtx body = PATTERN (insn);
|
|||
|
rtx cond = 0;
|
|||
|
|
|||
|
body = PATTERN (insn);
|
|||
|
if (GET_CODE (body) == COND_EXEC)
|
|||
|
{
|
|||
|
cond = COND_EXEC_TEST (body);
|
|||
|
body = COND_EXEC_CODE (body);
|
|||
|
}
|
|||
|
|
|||
|
/* Find all sets. */
|
|||
|
if (GET_CODE (body) == SET)
|
|||
|
{
|
|||
|
sets[0].src = SET_SRC (body);
|
|||
|
sets[0].dest = SET_DEST (body);
|
|||
|
n_sets = 1;
|
|||
|
}
|
|||
|
else if (GET_CODE (body) == PARALLEL)
|
|||
|
{
|
|||
|
/* Look through the PARALLEL and record the values being
|
|||
|
set, if possible. Also handle any CLOBBERs. */
|
|||
|
for (i = XVECLEN (body, 0) - 1; i >= 0; --i)
|
|||
|
{
|
|||
|
rtx x = XVECEXP (body, 0, i);
|
|||
|
|
|||
|
if (GET_CODE (x) == SET)
|
|||
|
{
|
|||
|
sets[n_sets].src = SET_SRC (x);
|
|||
|
sets[n_sets].dest = SET_DEST (x);
|
|||
|
n_sets++;
|
|||
|
}
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
if (n_sets == 1
|
|||
|
&& MEM_P (sets[0].src)
|
|||
|
&& !cselib_record_memory
|
|||
|
&& MEM_READONLY_P (sets[0].src))
|
|||
|
{
|
|||
|
rtx note = find_reg_equal_equiv_note (insn);
|
|||
|
|
|||
|
if (note && CONSTANT_P (XEXP (note, 0)))
|
|||
|
sets[0].src = XEXP (note, 0);
|
|||
|
}
|
|||
|
|
|||
|
/* Look up the values that are read. Do this before invalidating the
|
|||
|
locations that are written. */
|
|||
|
for (i = 0; i < n_sets; i++)
|
|||
|
{
|
|||
|
rtx dest = sets[i].dest;
|
|||
|
|
|||
|
/* A STRICT_LOW_PART can be ignored; we'll record the equivalence for
|
|||
|
the low part after invalidating any knowledge about larger modes. */
|
|||
|
if (GET_CODE (sets[i].dest) == STRICT_LOW_PART)
|
|||
|
sets[i].dest = dest = XEXP (dest, 0);
|
|||
|
|
|||
|
/* We don't know how to record anything but REG or MEM. */
|
|||
|
if (REG_P (dest)
|
|||
|
|| (MEM_P (dest) && cselib_record_memory))
|
|||
|
{
|
|||
|
rtx src = sets[i].src;
|
|||
|
if (cond)
|
|||
|
src = gen_rtx_IF_THEN_ELSE (GET_MODE (dest), cond, src, dest);
|
|||
|
sets[i].src_elt = cselib_lookup (src, GET_MODE (dest), 1);
|
|||
|
if (MEM_P (dest))
|
|||
|
{
|
|||
|
enum machine_mode address_mode
|
|||
|
= targetm.addr_space.address_mode (MEM_ADDR_SPACE (dest));
|
|||
|
|
|||
|
sets[i].dest_addr_elt = cselib_lookup (XEXP (dest, 0),
|
|||
|
address_mode, 1);
|
|||
|
}
|
|||
|
else
|
|||
|
sets[i].dest_addr_elt = 0;
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
if (cselib_record_sets_hook)
|
|||
|
cselib_record_sets_hook (insn, sets, n_sets);
|
|||
|
|
|||
|
/* Invalidate all locations written by this insn. Note that the elts we
|
|||
|
looked up in the previous loop aren't affected, just some of their
|
|||
|
locations may go away. */
|
|||
|
note_stores (body, cselib_invalidate_rtx_note_stores, NULL);
|
|||
|
|
|||
|
/* If this is an asm, look for duplicate sets. This can happen when the
|
|||
|
user uses the same value as an output multiple times. This is valid
|
|||
|
if the outputs are not actually used thereafter. Treat this case as
|
|||
|
if the value isn't actually set. We do this by smashing the destination
|
|||
|
to pc_rtx, so that we won't record the value later. */
|
|||
|
if (n_sets >= 2 && asm_noperands (body) >= 0)
|
|||
|
{
|
|||
|
for (i = 0; i < n_sets; i++)
|
|||
|
{
|
|||
|
rtx dest = sets[i].dest;
|
|||
|
if (REG_P (dest) || MEM_P (dest))
|
|||
|
{
|
|||
|
int j;
|
|||
|
for (j = i + 1; j < n_sets; j++)
|
|||
|
if (rtx_equal_p (dest, sets[j].dest))
|
|||
|
{
|
|||
|
sets[i].dest = pc_rtx;
|
|||
|
sets[j].dest = pc_rtx;
|
|||
|
}
|
|||
|
}
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
/* Now enter the equivalences in our tables. */
|
|||
|
for (i = 0; i < n_sets; i++)
|
|||
|
{
|
|||
|
rtx dest = sets[i].dest;
|
|||
|
if (REG_P (dest)
|
|||
|
|| (MEM_P (dest) && cselib_record_memory))
|
|||
|
cselib_record_set (dest, sets[i].src_elt, sets[i].dest_addr_elt);
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
/* Record the effects of INSN. */
|
|||
|
|
|||
|
void
|
|||
|
cselib_process_insn (rtx insn)
|
|||
|
{
|
|||
|
int i;
|
|||
|
rtx x;
|
|||
|
|
|||
|
cselib_current_insn = insn;
|
|||
|
|
|||
|
/* Forget everything at a CODE_LABEL, a volatile asm, or a setjmp. */
|
|||
|
if (LABEL_P (insn)
|
|||
|
|| (CALL_P (insn)
|
|||
|
&& find_reg_note (insn, REG_SETJMP, NULL))
|
|||
|
|| (NONJUMP_INSN_P (insn)
|
|||
|
&& GET_CODE (PATTERN (insn)) == ASM_OPERANDS
|
|||
|
&& MEM_VOLATILE_P (PATTERN (insn))))
|
|||
|
{
|
|||
|
cselib_reset_table (next_uid);
|
|||
|
cselib_current_insn = NULL_RTX;
|
|||
|
return;
|
|||
|
}
|
|||
|
|
|||
|
if (! INSN_P (insn))
|
|||
|
{
|
|||
|
cselib_current_insn = NULL_RTX;
|
|||
|
return;
|
|||
|
}
|
|||
|
|
|||
|
/* If this is a call instruction, forget anything stored in a
|
|||
|
call clobbered register, or, if this is not a const call, in
|
|||
|
memory. */
|
|||
|
if (CALL_P (insn))
|
|||
|
{
|
|||
|
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
|
|||
|
if (call_used_regs[i]
|
|||
|
|| (REG_VALUES (i) && REG_VALUES (i)->elt
|
|||
|
&& HARD_REGNO_CALL_PART_CLOBBERED (i,
|
|||
|
GET_MODE (REG_VALUES (i)->elt->val_rtx))))
|
|||
|
cselib_invalidate_regno (i, reg_raw_mode[i]);
|
|||
|
|
|||
|
/* Since it is not clear how cselib is going to be used, be
|
|||
|
conservative here and treat looping pure or const functions
|
|||
|
as if they were regular functions. */
|
|||
|
if (RTL_LOOPING_CONST_OR_PURE_CALL_P (insn)
|
|||
|
|| !(RTL_CONST_OR_PURE_CALL_P (insn)))
|
|||
|
cselib_invalidate_mem (callmem);
|
|||
|
}
|
|||
|
|
|||
|
cselib_record_sets (insn);
|
|||
|
|
|||
|
#ifdef AUTO_INC_DEC
|
|||
|
/* Clobber any registers which appear in REG_INC notes. We
|
|||
|
could keep track of the changes to their values, but it is
|
|||
|
unlikely to help. */
|
|||
|
for (x = REG_NOTES (insn); x; x = XEXP (x, 1))
|
|||
|
if (REG_NOTE_KIND (x) == REG_INC)
|
|||
|
cselib_invalidate_rtx (XEXP (x, 0));
|
|||
|
#endif
|
|||
|
|
|||
|
/* Look for any CLOBBERs in CALL_INSN_FUNCTION_USAGE, but only
|
|||
|
after we have processed the insn. */
|
|||
|
if (CALL_P (insn))
|
|||
|
for (x = CALL_INSN_FUNCTION_USAGE (insn); x; x = XEXP (x, 1))
|
|||
|
if (GET_CODE (XEXP (x, 0)) == CLOBBER)
|
|||
|
cselib_invalidate_rtx (XEXP (XEXP (x, 0), 0));
|
|||
|
|
|||
|
cselib_current_insn = NULL_RTX;
|
|||
|
|
|||
|
if (n_useless_values > MAX_USELESS_VALUES
|
|||
|
/* remove_useless_values is linear in the hash table size. Avoid
|
|||
|
quadratic behavior for very large hashtables with very few
|
|||
|
useless elements. */
|
|||
|
&& ((unsigned int)n_useless_values
|
|||
|
> (cselib_hash_table->n_elements
|
|||
|
- cselib_hash_table->n_deleted
|
|||
|
- n_debug_values) / 4))
|
|||
|
remove_useless_values ();
|
|||
|
}
|
|||
|
|
|||
|
/* Initialize cselib for one pass. The caller must also call
|
|||
|
init_alias_analysis. */
|
|||
|
|
|||
|
void
|
|||
|
cselib_init (int record_what)
|
|||
|
{
|
|||
|
elt_list_pool = create_alloc_pool ("elt_list",
|
|||
|
sizeof (struct elt_list), 10);
|
|||
|
elt_loc_list_pool = create_alloc_pool ("elt_loc_list",
|
|||
|
sizeof (struct elt_loc_list), 10);
|
|||
|
cselib_val_pool = create_alloc_pool ("cselib_val_list",
|
|||
|
sizeof (cselib_val), 10);
|
|||
|
value_pool = create_alloc_pool ("value", RTX_CODE_SIZE (VALUE), 100);
|
|||
|
cselib_record_memory = record_what & CSELIB_RECORD_MEMORY;
|
|||
|
cselib_preserve_constants = record_what & CSELIB_PRESERVE_CONSTANTS;
|
|||
|
|
|||
|
/* (mem:BLK (scratch)) is a special mechanism to conflict with everything,
|
|||
|
see canon_true_dependence. This is only created once. */
|
|||
|
if (! callmem)
|
|||
|
callmem = gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (VOIDmode));
|
|||
|
|
|||
|
cselib_nregs = max_reg_num ();
|
|||
|
|
|||
|
/* We preserve reg_values to allow expensive clearing of the whole thing.
|
|||
|
Reallocate it however if it happens to be too large. */
|
|||
|
if (!reg_values || reg_values_size < cselib_nregs
|
|||
|
|| (reg_values_size > 10 && reg_values_size > cselib_nregs * 4))
|
|||
|
{
|
|||
|
if (reg_values)
|
|||
|
free (reg_values);
|
|||
|
/* Some space for newly emit instructions so we don't end up
|
|||
|
reallocating in between passes. */
|
|||
|
reg_values_size = cselib_nregs + (63 + cselib_nregs) / 16;
|
|||
|
reg_values = XCNEWVEC (struct elt_list *, reg_values_size);
|
|||
|
}
|
|||
|
used_regs = XNEWVEC (unsigned int, cselib_nregs);
|
|||
|
n_used_regs = 0;
|
|||
|
cselib_hash_table = htab_create (31, get_value_hash,
|
|||
|
entry_and_rtx_equal_p, NULL);
|
|||
|
next_uid = 1;
|
|||
|
}
|
|||
|
|
|||
|
/* Called when the current user is done with cselib. */
|
|||
|
|
|||
|
void
|
|||
|
cselib_finish (void)
|
|||
|
{
|
|||
|
cselib_discard_hook = NULL;
|
|||
|
cselib_preserve_constants = false;
|
|||
|
cfa_base_preserved_val = NULL;
|
|||
|
free_alloc_pool (elt_list_pool);
|
|||
|
free_alloc_pool (elt_loc_list_pool);
|
|||
|
free_alloc_pool (cselib_val_pool);
|
|||
|
free_alloc_pool (value_pool);
|
|||
|
cselib_clear_table ();
|
|||
|
htab_delete (cselib_hash_table);
|
|||
|
free (used_regs);
|
|||
|
used_regs = 0;
|
|||
|
cselib_hash_table = 0;
|
|||
|
n_useless_values = 0;
|
|||
|
n_useless_debug_values = 0;
|
|||
|
n_debug_values = 0;
|
|||
|
next_uid = 0;
|
|||
|
}
|
|||
|
|
|||
|
/* Dump the cselib_val *X to FILE *info. */
|
|||
|
|
|||
|
static int
|
|||
|
dump_cselib_val (void **x, void *info)
|
|||
|
{
|
|||
|
cselib_val *v = (cselib_val *)*x;
|
|||
|
FILE *out = (FILE *)info;
|
|||
|
bool need_lf = true;
|
|||
|
|
|||
|
print_inline_rtx (out, v->val_rtx, 0);
|
|||
|
|
|||
|
if (v->locs)
|
|||
|
{
|
|||
|
struct elt_loc_list *l = v->locs;
|
|||
|
if (need_lf)
|
|||
|
{
|
|||
|
fputc ('\n', out);
|
|||
|
need_lf = false;
|
|||
|
}
|
|||
|
fputs (" locs:", out);
|
|||
|
do
|
|||
|
{
|
|||
|
fprintf (out, "\n from insn %i ",
|
|||
|
INSN_UID (l->setting_insn));
|
|||
|
print_inline_rtx (out, l->loc, 4);
|
|||
|
}
|
|||
|
while ((l = l->next));
|
|||
|
fputc ('\n', out);
|
|||
|
}
|
|||
|
else
|
|||
|
{
|
|||
|
fputs (" no locs", out);
|
|||
|
need_lf = true;
|
|||
|
}
|
|||
|
|
|||
|
if (v->addr_list)
|
|||
|
{
|
|||
|
struct elt_list *e = v->addr_list;
|
|||
|
if (need_lf)
|
|||
|
{
|
|||
|
fputc ('\n', out);
|
|||
|
need_lf = false;
|
|||
|
}
|
|||
|
fputs (" addr list:", out);
|
|||
|
do
|
|||
|
{
|
|||
|
fputs ("\n ", out);
|
|||
|
print_inline_rtx (out, e->elt->val_rtx, 2);
|
|||
|
}
|
|||
|
while ((e = e->next));
|
|||
|
fputc ('\n', out);
|
|||
|
}
|
|||
|
else
|
|||
|
{
|
|||
|
fputs (" no addrs", out);
|
|||
|
need_lf = true;
|
|||
|
}
|
|||
|
|
|||
|
if (v->next_containing_mem == &dummy_val)
|
|||
|
fputs (" last mem\n", out);
|
|||
|
else if (v->next_containing_mem)
|
|||
|
{
|
|||
|
fputs (" next mem ", out);
|
|||
|
print_inline_rtx (out, v->next_containing_mem->val_rtx, 2);
|
|||
|
fputc ('\n', out);
|
|||
|
}
|
|||
|
else if (need_lf)
|
|||
|
fputc ('\n', out);
|
|||
|
|
|||
|
return 1;
|
|||
|
}
|
|||
|
|
|||
|
/* Dump to OUT everything in the CSELIB table. */
|
|||
|
|
|||
|
void
|
|||
|
dump_cselib_table (FILE *out)
|
|||
|
{
|
|||
|
fprintf (out, "cselib hash table:\n");
|
|||
|
htab_traverse (cselib_hash_table, dump_cselib_val, out);
|
|||
|
if (first_containing_mem != &dummy_val)
|
|||
|
{
|
|||
|
fputs ("first mem ", out);
|
|||
|
print_inline_rtx (out, first_containing_mem->val_rtx, 2);
|
|||
|
fputc ('\n', out);
|
|||
|
}
|
|||
|
fprintf (out, "next uid %i\n", next_uid);
|
|||
|
}
|
|||
|
|
|||
|
#include "gt-cselib.h"
|