/* Common subexpression elimination library for GNU compiler.
Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
- 1999, 2000, 2001, 2003, 2004 Free Software Foundation, Inc.
+ 1999, 2000, 2001, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011,
+ 2012 Free Software Foundation, Inc.
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
-Software Foundation; either version 2, or (at your option) any later
+Software Foundation; either version 3, or (at your option) any later
version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
for more details.
You should have received a copy of the GNU General Public License
-along with GCC; see the file COPYING. If not, write to the Free
-Software Foundation, 59 Temple Place - Suite 330, Boston, MA
-02111-1307, USA. */
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
#include "config.h"
#include "system.h"
#include "regs.h"
#include "hard-reg-set.h"
#include "flags.h"
-#include "real.h"
#include "insn-config.h"
#include "recog.h"
#include "function.h"
-#include "expr.h"
-#include "toplev.h"
+#include "emit-rtl.h"
+#include "diagnostic-core.h"
#include "output.h"
#include "ggc.h"
#include "hashtab.h"
+#include "tree-pass.h"
#include "cselib.h"
#include "params.h"
#include "alloc-pool.h"
+#include "target.h"
+#include "bitmap.h"
+/* A list of cselib_val structures. */
+struct elt_list {
+ struct elt_list *next;
+ cselib_val *elt;
+};
+
+static bool cselib_record_memory;
+static bool cselib_preserve_constants;
static int entry_and_rtx_equal_p (const void *, const void *);
static hashval_t get_value_hash (const void *);
static struct elt_list *new_elt_list (struct elt_list *, cselib_val *);
-static struct elt_loc_list *new_elt_loc_list (struct elt_loc_list *, rtx);
+static void new_elt_loc_list (cselib_val *, rtx);
static void unchain_one_value (cselib_val *);
static void unchain_one_elt_list (struct elt_list **);
static void unchain_one_elt_loc_list (struct elt_loc_list **);
-static void clear_table (void);
static int discard_useless_locs (void **, void *);
static int discard_useless_values (void **, void *);
static void remove_useless_values (void);
-static rtx wrap_constant (enum machine_mode, rtx);
-static unsigned int hash_rtx (rtx, enum machine_mode, int);
-static cselib_val *new_cselib_val (unsigned int, enum machine_mode);
+static int rtx_equal_for_cselib_1 (rtx, rtx, enum machine_mode);
+static unsigned int cselib_hash_rtx (rtx, int, enum machine_mode);
+static cselib_val *new_cselib_val (unsigned int, enum machine_mode, rtx);
static void add_mem_for_addr (cselib_val *, cselib_val *, rtx);
static cselib_val *cselib_lookup_mem (rtx, int);
static void cselib_invalidate_regno (unsigned int, enum machine_mode);
static void cselib_invalidate_mem (rtx);
-static void cselib_invalidate_rtx (rtx, rtx, void *);
static void cselib_record_set (rtx, cselib_val *, cselib_val *);
static void cselib_record_sets (rtx);
+struct expand_value_data
+{
+ bitmap regs_active;
+ cselib_expand_callback callback;
+ void *callback_arg;
+ bool dummy;
+};
+
+static rtx cselib_expand_value_rtx_1 (rtx, struct expand_value_data *, int);
+
/* There are three ways in which cselib can look up an rtx:
- for a REG, the reg_values table (which is indexed by regno) is used
- for a MEM, we recursively look up its address and then follow the
the locations of the entries with the rtx we are looking up. */
/* A table that enables us to look up elts by their value. */
-static htab_t hash_table;
+static htab_t cselib_hash_table;
/* This is a global so we don't have to pass this through every function.
It is used in new_elt_loc_list to set SETTING_INSN. */
static rtx cselib_current_insn;
-static bool cselib_current_insn_in_libcall;
-/* Every new unknown value gets a unique number. */
-static unsigned int next_unknown_value;
+/* The unique id that the next create value will take. */
+static unsigned int next_uid;
/* The number of registers we had when the varrays were last resized. */
static unsigned int cselib_nregs;
-/* Count values without known locations. Whenever this grows too big, we
- remove these useless values from the table. */
+/* Count values without known locations, or with only locations that
+ wouldn't have been known except for debug insns. Whenever this
+ grows too big, we remove these useless values from the table.
+
+ Counting values with only debug values is a bit tricky. We don't
+ want to increment n_useless_values when we create a value for a
+ debug insn, for this would get n_useless_values out of sync, but we
+ want increment it if all locs in the list that were ever referenced
+ in nondebug insns are removed from the list.
+
+ In the general case, once we do that, we'd have to stop accepting
+ nondebug expressions in the loc list, to avoid having two values
+ equivalent that, without debug insns, would have been made into
+ separate values. However, because debug insns never introduce
+ equivalences themselves (no assignments), the only means for
+ growing loc lists is through nondebug assignments. If the locs
+ also happen to be referenced in debug insns, it will work just fine.
+
+ A consequence of this is that there's at most one debug-only loc in
+ each loc list. If we keep it in the first entry, testing whether
+ we have a debug-only loc list takes O(1).
+
+ Furthermore, since any additional entry in a loc list containing a
+ debug loc would have to come from an assignment (nondebug) that
+ references both the initial debug loc and the newly-equivalent loc,
+ the initial debug loc would be promoted to a nondebug loc, and the
+ loc list would not contain debug locs any more.
+
+ So the only case we have to be careful with in order to keep
+ n_useless_values in sync between debug and nondebug compilations is
+ to avoid incrementing n_useless_values when removing the single loc
+ from a value that turns out to not appear outside debug values. We
+ increment n_useless_debug_values instead, and leave such values
+ alone until, for other reasons, we garbage-collect useless
+ values. */
static int n_useless_values;
+static int n_useless_debug_values;
+
+/* Count values whose locs have been taken exclusively from debug
+ insns for the entire life of the value. */
+static int n_debug_values;
/* Number of useless values before we remove them from the hash table. */
#define MAX_USELESS_VALUES 32
which the register was set; if the mode is unknown or the value is
no longer valid in that mode, ELT will be NULL for the first
element. */
-struct elt_list **reg_values;
-unsigned int reg_values_size;
+static struct elt_list **reg_values;
+static unsigned int reg_values_size;
#define REG_VALUES(i) reg_values[i]
/* The largest number of hard regs used by any entry added to the
- REG_VALUES table. Cleared on each clear_table() invocation. */
+ REG_VALUES table. Cleared on each cselib_clear_table() invocation. */
static unsigned int max_value_regs;
/* Here the set of indices I with REG_VALUES(I) != 0 is saved. This is used
- in clear_table() for fast emptying. */
+ in cselib_clear_table() for fast emptying. */
static unsigned int *used_regs;
static unsigned int n_used_regs;
presence in the list by checking the next pointer. */
static cselib_val dummy_val;
+/* If non-NULL, value of the eliminated arg_pointer_rtx or frame_pointer_rtx
+ that is constant through the whole function and should never be
+ eliminated. */
+static cselib_val *cfa_base_preserved_val;
+static unsigned int cfa_base_preserved_regno = INVALID_REGNUM;
+
/* Used to list all values that contain memory reference.
May or may not contain the useless values - the list is compacted
each time memory is invalidated. */
static cselib_val *first_containing_mem = &dummy_val;
static alloc_pool elt_loc_list_pool, elt_list_pool, cselib_val_pool, value_pool;
+
+/* If nonnull, cselib will call this function before freeing useless
+ VALUEs. A VALUE is deemed useless if its "locs" field is null. */
+void (*cselib_discard_hook) (cselib_val *);
+
+/* If nonnull, cselib will call this function before recording sets or
+ even clobbering outputs of INSN. All the recorded sets will be
+ represented in the array sets[n_sets]. new_val_min can be used to
+ tell whether values present in sets are introduced by this
+ instruction. */
+void (*cselib_record_sets_hook) (rtx insn, struct cselib_set *sets,
+ int n_sets);
+
+#define PRESERVED_VALUE_P(RTX) \
+ (RTL_FLAG_CHECK1("PRESERVED_VALUE_P", (RTX), VALUE)->unchanging)
+
\f
/* Allocate a struct elt_list and fill in its two elements with the
new_elt_list (struct elt_list *next, cselib_val *elt)
{
struct elt_list *el;
- el = pool_alloc (elt_list_pool);
+ el = (struct elt_list *) pool_alloc (elt_list_pool);
el->next = next;
el->elt = elt;
return el;
}
-/* Allocate a struct elt_loc_list and fill in its two elements with the
- arguments. */
+/* Allocate a struct elt_loc_list with LOC and prepend it to VAL's loc
+ list. */
-static inline struct elt_loc_list *
-new_elt_loc_list (struct elt_loc_list *next, rtx loc)
+static inline void
+new_elt_loc_list (cselib_val *val, rtx loc)
{
- struct elt_loc_list *el;
- el = pool_alloc (elt_loc_list_pool);
- el->next = next;
+ struct elt_loc_list *el, *next = val->locs;
+
+ gcc_checking_assert (!next || !next->setting_insn
+ || !DEBUG_INSN_P (next->setting_insn)
+ || cselib_current_insn == next->setting_insn);
+
+ /* If we're creating the first loc in a debug insn context, we've
+ just created a debug value. Count it. */
+ if (!next && cselib_current_insn && DEBUG_INSN_P (cselib_current_insn))
+ n_debug_values++;
+
+ val = canonical_cselib_val (val);
+ next = val->locs;
+
+ if (GET_CODE (loc) == VALUE)
+ {
+ loc = canonical_cselib_val (CSELIB_VAL_PTR (loc))->val_rtx;
+
+ gcc_checking_assert (PRESERVED_VALUE_P (loc)
+ == PRESERVED_VALUE_P (val->val_rtx));
+
+ if (val->val_rtx == loc)
+ return;
+ else if (val->uid > CSELIB_VAL_PTR (loc)->uid)
+ {
+ /* Reverse the insertion. */
+ new_elt_loc_list (CSELIB_VAL_PTR (loc), val->val_rtx);
+ return;
+ }
+
+ gcc_checking_assert (val->uid < CSELIB_VAL_PTR (loc)->uid);
+
+ if (CSELIB_VAL_PTR (loc)->locs)
+ {
+ /* Bring all locs from LOC to VAL. */
+ for (el = CSELIB_VAL_PTR (loc)->locs; el->next; el = el->next)
+ {
+ /* Adjust values that have LOC as canonical so that VAL
+ becomes their canonical. */
+ if (el->loc && GET_CODE (el->loc) == VALUE)
+ {
+ gcc_checking_assert (CSELIB_VAL_PTR (el->loc)->locs->loc
+ == loc);
+ CSELIB_VAL_PTR (el->loc)->locs->loc = val->val_rtx;
+ }
+ }
+ el->next = val->locs;
+ next = val->locs = CSELIB_VAL_PTR (loc)->locs;
+ }
+
+ if (CSELIB_VAL_PTR (loc)->addr_list)
+ {
+ /* Bring in addr_list into canonical node. */
+ struct elt_list *last = CSELIB_VAL_PTR (loc)->addr_list;
+ while (last->next)
+ last = last->next;
+ last->next = val->addr_list;
+ val->addr_list = CSELIB_VAL_PTR (loc)->addr_list;
+ CSELIB_VAL_PTR (loc)->addr_list = NULL;
+ }
+
+ if (CSELIB_VAL_PTR (loc)->next_containing_mem != NULL
+ && val->next_containing_mem == NULL)
+ {
+ /* Add VAL to the containing_mem list after LOC. LOC will
+ be removed when we notice it doesn't contain any
+ MEMs. */
+ val->next_containing_mem = CSELIB_VAL_PTR (loc)->next_containing_mem;
+ CSELIB_VAL_PTR (loc)->next_containing_mem = val;
+ }
+
+ /* Chain LOC back to VAL. */
+ el = (struct elt_loc_list *) pool_alloc (elt_loc_list_pool);
+ el->loc = val->val_rtx;
+ el->setting_insn = cselib_current_insn;
+ el->next = NULL;
+ CSELIB_VAL_PTR (loc)->locs = el;
+ }
+
+ el = (struct elt_loc_list *) pool_alloc (elt_loc_list_pool);
el->loc = loc;
- el->canon_loc = NULL;
el->setting_insn = cselib_current_insn;
- el->in_libcall = cselib_current_insn_in_libcall;
- return el;
+ el->next = next;
+ val->locs = el;
+}
+
+/* Promote loc L to a nondebug cselib_current_insn if L is marked as
+ originating from a debug insn, maintaining the debug values
+ count. */
+
+static inline void
+promote_debug_loc (struct elt_loc_list *l)
+{
+ if (l->setting_insn && DEBUG_INSN_P (l->setting_insn)
+ && (!cselib_current_insn || !DEBUG_INSN_P (cselib_current_insn)))
+ {
+ n_debug_values--;
+ l->setting_insn = cselib_current_insn;
+ if (cselib_preserve_constants && l->next)
+ {
+ gcc_assert (l->next->setting_insn
+ && DEBUG_INSN_P (l->next->setting_insn)
+ && !l->next->next);
+ l->next->setting_insn = cselib_current_insn;
+ }
+ else
+ gcc_assert (!l->next);
+ }
}
/* The elt_list at *PL is no longer needed. Unchain it and free its
}
/* Remove all entries from the hash table. Also used during
- initialization. If CLEAR_ALL isn't set, then only clear the entries
- which are known to have been used. */
+ initialization. */
-static void
-clear_table (void)
+void
+cselib_clear_table (void)
{
- unsigned int i;
+ cselib_reset_table (1);
+}
+
+/* Remove from hash table all VALUEs except constants
+ and function invariants. */
+
+static int
+preserve_only_constants (void **x, void *info ATTRIBUTE_UNUSED)
+{
+ cselib_val *v = (cselib_val *)*x;
+ struct elt_loc_list *l;
+
+ if (v->locs != NULL
+ && v->locs->next == NULL)
+ {
+ if (CONSTANT_P (v->locs->loc)
+ && (GET_CODE (v->locs->loc) != CONST
+ || !references_value_p (v->locs->loc, 0)))
+ return 1;
+ /* Although a debug expr may be bound to different expressions,
+ we can preserve it as if it was constant, to get unification
+ and proper merging within var-tracking. */
+ if (GET_CODE (v->locs->loc) == DEBUG_EXPR
+ || GET_CODE (v->locs->loc) == DEBUG_IMPLICIT_PTR
+ || GET_CODE (v->locs->loc) == ENTRY_VALUE
+ || GET_CODE (v->locs->loc) == DEBUG_PARAMETER_REF)
+ return 1;
+ if (cfa_base_preserved_val)
+ {
+ if (v == cfa_base_preserved_val)
+ return 1;
+ if (GET_CODE (v->locs->loc) == PLUS
+ && CONST_INT_P (XEXP (v->locs->loc, 1))
+ && XEXP (v->locs->loc, 0) == cfa_base_preserved_val->val_rtx)
+ return 1;
+ }
+ }
- for (i = 0; i < n_used_regs; i++)
- REG_VALUES (used_regs[i]) = 0;
+ /* Keep VALUE equivalences around. */
+ for (l = v->locs; l; l = l->next)
+ if (GET_CODE (l->loc) == VALUE)
+ return 1;
+
+ htab_clear_slot (cselib_hash_table, x);
+ return 1;
+}
+
+/* Remove all entries from the hash table, arranging for the next
+ value to be numbered NUM. */
+
+void
+cselib_reset_table (unsigned int num)
+{
+ unsigned int i;
max_value_regs = 0;
- n_used_regs = 0;
+ if (cfa_base_preserved_val)
+ {
+ unsigned int regno = cfa_base_preserved_regno;
+ 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;
+ }
- htab_empty (hash_table);
+ 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_unknown_value = 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;
+}
+
+/* See the documentation of cselib_find_slot below. */
+static enum machine_mode find_slot_memmode;
+
+/* Search for X, whose hashcode is HASH, in CSELIB_HASH_TABLE,
+ INSERTing if requested. When X is part of the address of a MEM,
+ MEMMODE should specify the mode of the MEM. While searching the
+ table, MEMMODE is held in FIND_SLOT_MEMMODE, so that autoinc RTXs
+ in X can be resolved. */
+
+static void **
+cselib_find_slot (rtx x, hashval_t hash, enum insert_option insert,
+ enum machine_mode memmode)
+{
+ void **slot;
+ find_slot_memmode = memmode;
+ slot = htab_find_slot_with_hash (cselib_hash_table, x, hash, insert);
+ find_slot_memmode = VOIDmode;
+ return slot;
+}
+
/* 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
entry_and_rtx_equal_p (const void *entry, const void *x_arg)
{
struct elt_loc_list *l;
- const cselib_val *v = (const cselib_val *) entry;
- rtx x = (rtx) x_arg;
+ 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);
- if (GET_CODE (x) == CONST_INT
- || (mode == VOIDmode && GET_CODE (x) == CONST_DOUBLE))
- abort ();
- if (mode != GET_MODE (v->u.val_rtx))
+ 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
- && (GET_CODE (XEXP (x, 0)) == CONST_INT
+ && (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))
- return 1;
+ if (rtx_equal_for_cselib_1 (l->loc, x, find_slot_memmode))
+ {
+ promote_debug_loc (l);
+ return 1;
+ }
return 0;
}
/* The hash function for our hash table. The value is always computed with
- hash_rtx when adding an element; this function just extracts the hash
- value from a cselib_val structure. */
+ 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 *v = (const cselib_val *) entry;
- return v->value;
+ 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
removed. */
int
-references_value_p (rtx x, int only_useless)
+references_value_p (const_rtx x, int only_useless)
{
- enum rtx_code code = GET_CODE (x);
+ 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))
+ && (! only_useless ||
+ (CSELIB_VAL_PTR (x)->locs == 0 && !PRESERVED_VALUE_P (x))))
return 1;
for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
{
cselib_val *v = (cselib_val *)*x;
struct elt_loc_list **p = &v->locs;
- int had_locs = v->locs != 0;
+ bool had_locs = v->locs != NULL;
+ rtx setting_insn = v->locs ? v->locs->setting_insn : NULL;
while (*p)
{
p = &(*p)->next;
}
- if (had_locs && v->locs == 0)
+ if (had_locs && v->locs == 0 && !PRESERVED_VALUE_P (v->val_rtx))
{
- n_useless_values++;
+ if (setting_insn && DEBUG_INSN_P (setting_insn))
+ n_useless_debug_values++;
+ else
+ n_useless_values++;
values_became_useless = 1;
}
return 1;
{
cselib_val *v = (cselib_val *)*x;
- if (v->locs == 0)
+ if (v->locs == 0 && !PRESERVED_VALUE_P (v->val_rtx))
{
- CSELIB_VAL_PTR (v->u.val_rtx) = NULL;
- htab_clear_slot (hash_table, x);
+ 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--;
}
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 (hash_table, discard_useless_locs, 0);
+ htab_traverse (cselib_hash_table, discard_useless_locs, 0);
}
while (values_became_useless);
p = &first_containing_mem;
for (v = *p; v != &dummy_val; v = v->next_containing_mem)
- if (v->locs)
+ if (v->locs && v == canonical_cselib_val (v))
{
*p = v;
p = &(*p)->next_containing_mem;
}
*p = &dummy_val;
- htab_traverse (hash_table, discard_useless_values, 0);
+ 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, unsigned int regno)
+{
+ if (cselib_preserve_constants
+ && v->locs
+ && REG_P (v->locs->loc))
+ {
+ cfa_base_preserved_val = v;
+ cfa_base_preserved_regno = regno;
+ }
+}
+
+/* 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);
- if (n_useless_values != 0)
- abort ();
+ 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
VOIDmode. */
enum machine_mode
-cselib_reg_set_mode (rtx x)
+cselib_reg_set_mode (const_rtx x)
{
- if (GET_CODE (x) != REG)
+ 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->u.val_rtx);
+ 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
int
rtx_equal_for_cselib_p (rtx x, rtx y)
{
+ return rtx_equal_for_cselib_1 (x, y, VOIDmode);
+}
+
+/* If x is a PLUS or an autoinc operation, expand the operation,
+ storing the offset, if any, in *OFF. */
+
+static rtx
+autoinc_split (rtx x, rtx *off, enum machine_mode memmode)
+{
+ switch (GET_CODE (x))
+ {
+ case PLUS:
+ *off = XEXP (x, 1);
+ return XEXP (x, 0);
+
+ case PRE_DEC:
+ if (memmode == VOIDmode)
+ return x;
+
+ *off = GEN_INT (-GET_MODE_SIZE (memmode));
+ return XEXP (x, 0);
+ break;
+
+ case PRE_INC:
+ if (memmode == VOIDmode)
+ return x;
+
+ *off = GEN_INT (GET_MODE_SIZE (memmode));
+ return XEXP (x, 0);
+
+ case PRE_MODIFY:
+ return XEXP (x, 1);
+
+ case POST_DEC:
+ case POST_INC:
+ case POST_MODIFY:
+ return XEXP (x, 0);
+
+ default:
+ return x;
+ }
+}
+
+/* Return nonzero if we can prove that X and Y contain the same value,
+ taking our gathered information into account. MEMMODE holds the
+ mode of the enclosing MEM, if any, as required to deal with autoinc
+ addressing modes. If X and Y are not (known to be) part of
+ addresses, MEMMODE should be VOIDmode. */
+
+static int
+rtx_equal_for_cselib_1 (rtx x, rtx y, enum machine_mode memmode)
+{
enum rtx_code code;
const char *fmt;
int i;
- if (GET_CODE (x) == REG || GET_CODE (x) == MEM)
+ if (REG_P (x) || MEM_P (x))
{
- cselib_val *e = cselib_lookup (x, GET_MODE (x), 0);
+ cselib_val *e = cselib_lookup (x, GET_MODE (x), 0, memmode);
if (e)
- x = e->u.val_rtx;
+ x = e->val_rtx;
}
- if (GET_CODE (y) == REG || GET_CODE (y) == MEM)
+ if (REG_P (y) || MEM_P (y))
{
- cselib_val *e = cselib_lookup (y, GET_MODE (y), 0);
+ cselib_val *e = cselib_lookup (y, GET_MODE (y), 0, memmode);
if (e)
- y = e->u.val_rtx;
+ 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);
+ cselib_val *e = canonical_cselib_val (CSELIB_VAL_PTR (x));
struct elt_loc_list *l;
+ if (GET_CODE (y) == VALUE)
+ return e == canonical_cselib_val (CSELIB_VAL_PTR (y));
+
for (l = e->locs; l; l = l->next)
{
rtx t = l->loc;
- /* Avoid infinite recursion. */
- if (GET_CODE (t) == REG || GET_CODE (t) == MEM)
+ /* Avoid infinite recursion. We know we have the canonical
+ value, so we can just skip any values in the equivalence
+ list. */
+ if (REG_P (t) || MEM_P (t) || GET_CODE (t) == VALUE)
continue;
- else if (rtx_equal_for_cselib_p (t, y))
+ else if (rtx_equal_for_cselib_1 (t, y, memmode))
return 1;
}
return 0;
}
-
- if (GET_CODE (y) == VALUE)
+ else if (GET_CODE (y) == VALUE)
{
- cselib_val *e = CSELIB_VAL_PTR (y);
+ cselib_val *e = canonical_cselib_val (CSELIB_VAL_PTR (y));
struct elt_loc_list *l;
for (l = e->locs; l; l = l->next)
{
rtx t = l->loc;
- if (GET_CODE (t) == REG || GET_CODE (t) == MEM)
+ if (REG_P (t) || MEM_P (t) || GET_CODE (t) == VALUE)
continue;
- else if (rtx_equal_for_cselib_p (x, t))
+ else if (rtx_equal_for_cselib_1 (x, t, memmode))
return 1;
}
return 0;
}
- if (GET_CODE (x) != GET_CODE (y) || GET_MODE (x) != GET_MODE (y))
+ if (GET_MODE (x) != GET_MODE (y))
return 0;
- /* This won't be handled correctly by the code below. */
- if (GET_CODE (x) == LABEL_REF)
- return XEXP (x, 0) == XEXP (y, 0);
+ if (GET_CODE (x) != GET_CODE (y))
+ {
+ rtx xorig = x, yorig = y;
+ rtx xoff = NULL, yoff = NULL;
+
+ x = autoinc_split (x, &xoff, memmode);
+ y = autoinc_split (y, &yoff, memmode);
+
+ if (!xoff != !yoff)
+ return 0;
+
+ if (xoff && !rtx_equal_for_cselib_1 (xoff, yoff, memmode))
+ return 0;
+
+ /* Don't recurse if nothing changed. */
+ if (x != xorig || y != yorig)
+ return rtx_equal_for_cselib_1 (x, y, memmode);
+
+ 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 DEBUG_IMPLICIT_PTR:
+ return DEBUG_IMPLICIT_PTR_DECL (x)
+ == DEBUG_IMPLICIT_PTR_DECL (y);
+
+ case DEBUG_PARAMETER_REF:
+ return DEBUG_PARAMETER_REF_DECL (x)
+ == DEBUG_PARAMETER_REF_DECL (y);
+
+ case ENTRY_VALUE:
+ /* ENTRY_VALUEs are function invariant, it is thus undesirable to
+ use rtx_equal_for_cselib_1 to compare the operands. */
+ return rtx_equal_p (ENTRY_VALUE_EXP (x), ENTRY_VALUE_EXP (y));
+
+ case LABEL_REF:
+ return XEXP (x, 0) == XEXP (y, 0);
+
+ case MEM:
+ /* We have to compare any autoinc operations in the addresses
+ using this MEM's mode. */
+ return rtx_equal_for_cselib_1 (XEXP (x, 0), XEXP (y, 0), GET_MODE (x));
+
+ default:
+ break;
+ }
code = GET_CODE (x);
fmt = GET_RTX_FORMAT (code);
/* 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)))
+ if (! rtx_equal_for_cselib_1 (XVECEXP (x, i, j),
+ XVECEXP (y, i, j), memmode))
return 0;
break;
case 'e':
- if (! rtx_equal_for_cselib_p (XEXP (x, i), XEXP (y, i)))
+ if (i == 1
+ && targetm.commutative_p (x, UNKNOWN)
+ && rtx_equal_for_cselib_1 (XEXP (x, 1), XEXP (y, 0), memmode)
+ && rtx_equal_for_cselib_1 (XEXP (x, 0), XEXP (y, 1), memmode))
+ return 1;
+ if (! rtx_equal_for_cselib_1 (XEXP (x, i), XEXP (y, i), memmode))
return 0;
break;
contain anything but integers and other rtx's,
except for within LABEL_REFs and SYMBOL_REFs. */
default:
- abort ();
+ gcc_unreachable ();
}
}
return 1;
static rtx
wrap_constant (enum machine_mode mode, rtx x)
{
- if (GET_CODE (x) != CONST_INT
+ if (!CONST_INT_P (x) && GET_CODE (x) != CONST_FIXED
&& (GET_CODE (x) != CONST_DOUBLE || GET_MODE (x) != VOIDmode))
return x;
- if (mode == VOIDmode)
- abort ();
+ gcc_assert (mode != VOIDmode);
return gen_rtx_CONST (mode, x);
}
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.
- MODE is used in hashing for CONST_INTs only;
- otherwise the mode of X is used. */
+ 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) .
+ MEMMODE indicates the mode of an enclosing MEM, and it's only
+ used to compute autoinc values.
+ 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
-hash_rtx (rtx x, enum machine_mode mode, int create)
+cselib_hash_rtx (rtx x, int create, enum machine_mode memmode)
{
cselib_val *e;
int i, j;
switch (code)
{
+ case VALUE:
+ e = CSELIB_VAL_PTR (x);
+ return e->hash;
+
case MEM:
case REG:
- e = cselib_lookup (x, GET_MODE (x), create);
+ e = cselib_lookup (x, GET_MODE (x), create, memmode);
if (! e)
return 0;
- return e->value;
+ 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 DEBUG_IMPLICIT_PTR:
+ hash += ((unsigned) DEBUG_IMPLICIT_PTR << 7)
+ + DECL_UID (DEBUG_IMPLICIT_PTR_DECL (x));
+ return hash ? hash : (unsigned int) DEBUG_IMPLICIT_PTR;
+
+ case DEBUG_PARAMETER_REF:
+ hash += ((unsigned) DEBUG_PARAMETER_REF << 7)
+ + DECL_UID (DEBUG_PARAMETER_REF_DECL (x));
+ return hash ? hash : (unsigned int) DEBUG_PARAMETER_REF;
+
+ case ENTRY_VALUE:
+ /* ENTRY_VALUEs are function invariant, thus try to avoid
+ recursing on argument if ENTRY_VALUE is one of the
+ forms emitted by expand_debug_expr, otherwise
+ ENTRY_VALUE hash would depend on the current value
+ in some register or memory. */
+ if (REG_P (ENTRY_VALUE_EXP (x)))
+ hash += (unsigned int) REG
+ + (unsigned int) GET_MODE (ENTRY_VALUE_EXP (x))
+ + (unsigned int) REGNO (ENTRY_VALUE_EXP (x));
+ else if (MEM_P (ENTRY_VALUE_EXP (x))
+ && REG_P (XEXP (ENTRY_VALUE_EXP (x), 0)))
+ hash += (unsigned int) MEM
+ + (unsigned int) GET_MODE (XEXP (ENTRY_VALUE_EXP (x), 0))
+ + (unsigned int) REGNO (XEXP (ENTRY_VALUE_EXP (x), 0));
+ else
+ hash += cselib_hash_rtx (ENTRY_VALUE_EXP (x), create, memmode);
+ return hash ? hash : (unsigned int) ENTRY_VALUE;
case CONST_INT:
- hash += ((unsigned) CONST_INT << 7) + (unsigned) mode + INTVAL (x);
+ hash += ((unsigned) CONST_INT << 7) + INTVAL (x);
return hash ? hash : (unsigned int) CONST_INT;
case CONST_DOUBLE:
+ (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;
for (i = 0; i < units; ++i)
{
elt = CONST_VECTOR_ELT (x, i);
- hash += hash_rtx (elt, GET_MODE (elt), 0);
+ hash += cselib_hash_rtx (elt, 0, memmode);
}
return hash;
/* Assume there is only one rtx object for any given label. */
case LABEL_REF:
- hash
- += ((unsigned) LABEL_REF << 7) + (unsigned long) XEXP (x, 0);
+ /* 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:
- hash
- += ((unsigned) SYMBOL_REF << 7) + (unsigned long) XSTR (x, 0);
- return hash ? hash : (unsigned int) 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:
+ /* We can't compute these without knowing the MEM mode. */
+ gcc_assert (memmode != VOIDmode);
+ i = GET_MODE_SIZE (memmode);
+ if (code == PRE_DEC)
+ i = -i;
+ /* Adjust the hash so that (mem:MEMMODE (pre_* (reg))) hashes
+ like (mem:MEMMODE (plus (reg) (const_int I))). */
+ hash += (unsigned) PLUS - (unsigned)code
+ + cselib_hash_rtx (XEXP (x, 0), create, memmode)
+ + cselib_hash_rtx (GEN_INT (i), create, memmode);
+ return hash ? hash : 1 + (unsigned) PLUS;
+
+ case PRE_MODIFY:
+ gcc_assert (memmode != VOIDmode);
+ return cselib_hash_rtx (XEXP (x, 1), create, memmode);
+
case POST_DEC:
case POST_INC:
case POST_MODIFY:
- case PRE_MODIFY:
+ gcc_assert (memmode != VOIDmode);
+ return cselib_hash_rtx (XEXP (x, 0), create, memmode);
+
case PC:
case CC0:
case CALL:
fmt = GET_RTX_FORMAT (code);
for (; i >= 0; i--)
{
- if (fmt[i] == 'e')
+ switch (fmt[i])
{
- rtx tem = XEXP (x, i);
- unsigned int tem_hash = hash_rtx (tem, 0, create);
-
- if (tem_hash == 0)
- return 0;
-
- hash += tem_hash;
- }
- else if (fmt[i] == 'E')
- for (j = 0; j < XVECLEN (x, i); j++)
+ case 'e':
{
- unsigned int tem_hash = hash_rtx (XVECEXP (x, i, j), 0, create);
+ rtx tem = XEXP (x, i);
+ unsigned int tem_hash = cselib_hash_rtx (tem, create, memmode);
if (tem_hash == 0)
return 0;
hash += tem_hash;
}
- else if (fmt[i] == 's')
- {
- const unsigned char *p = (const unsigned char *) XSTR (x, i);
+ break;
+ case 'E':
+ for (j = 0; j < XVECLEN (x, i); j++)
+ {
+ unsigned int tem_hash
+ = cselib_hash_rtx (XVECEXP (x, i, j), create, memmode);
+
+ if (tem_hash == 0)
+ return 0;
+
+ hash += tem_hash;
+ }
+ break;
- if (p)
- while (*p)
- hash += *p++;
+ 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 ();
}
- else if (fmt[i] == 'i')
- hash += XINT (x, i);
- else if (fmt[i] == '0' || fmt[i] == 't')
- /* unused */;
- else
- abort ();
}
return hash ? hash : 1 + (unsigned int) GET_CODE (x);
value is MODE. */
static inline cselib_val *
-new_cselib_val (unsigned int value, enum machine_mode mode)
+new_cselib_val (unsigned int hash, enum machine_mode mode, rtx x)
{
- cselib_val *e = pool_alloc (cselib_val_pool);
-
-#ifdef ENABLE_CHECKING
- if (value == 0)
- abort ();
-#endif
-
- e->value = value;
- /* We use custom method to allocate this RTL construct because it accounts
- about 8% of overall memory usage. */
- e->u.val_rtx = pool_alloc (value_pool);
- memset (e->u.val_rtx, 0, RTX_HDR_SIZE);
- PUT_CODE (e->u.val_rtx, VALUE);
- PUT_MODE (e->u.val_rtx, mode);
- CSELIB_VAL_PTR (e->u.val_rtx) = e;
+ 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_CSELIB))
+ {
+ 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;
}
{
struct elt_loc_list *l;
+ addr_elt = canonical_cselib_val (addr_elt);
+ mem_elt = canonical_cselib_val (mem_elt);
+
/* Avoid duplicates. */
for (l = mem_elt->locs; l; l = l->next)
- if (GET_CODE (l->loc) == MEM
+ if (MEM_P (l->loc)
&& CSELIB_VAL_PTR (XEXP (l->loc, 0)) == addr_elt)
- return;
+ {
+ 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->u.val_rtx));
+ new_elt_loc_list (mem_elt,
+ replace_equiv_address_nv (x, addr_elt->val_rtx));
if (mem_elt->next_containing_mem == NULL)
{
mem_elt->next_containing_mem = first_containing_mem;
cselib_lookup_mem (rtx x, int create)
{
enum machine_mode mode = GET_MODE (x);
+ enum machine_mode addr_mode;
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;
+ addr_mode = GET_MODE (XEXP (x, 0));
+ if (addr_mode == VOIDmode)
+ addr_mode = Pmode;
+
/* Look up the value for the address. */
- addr = cselib_lookup (XEXP (x, 0), mode, create);
+ addr = cselib_lookup (XEXP (x, 0), addr_mode, create, mode);
if (! addr)
return 0;
+ addr = canonical_cselib_val (addr);
/* 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->u.val_rtx) == mode)
- return l->elt;
+ 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_unknown_value, mode);
+ mem_elt = new_cselib_val (next_uid, mode, x);
add_mem_for_addr (addr, mem_elt, x);
- slot = htab_find_slot_with_hash (hash_table, wrap_constant (mode, x),
- mem_elt->value, INSERT);
+ slot = cselib_find_slot (wrap_constant (mode, x), mem_elt->hash,
+ INSERT, mode);
*slot = mem_elt;
return mem_elt;
}
-/* 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. */
+/* 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. */
-rtx
-cselib_subst_to_values (rtx x)
+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)
+ {
+ /* Return these right away to avoid returning stack pointer based
+ expressions for frame pointer and vice versa, which is something
+ that would confuse DSE. See the comment in cselib_expand_value_rtx_1
+ for more details. */
+ if (REG_P (p->loc)
+ && (REGNO (p->loc) == STACK_POINTER_REGNUM
+ || REGNO (p->loc) == FRAME_POINTER_REGNUM
+ || REGNO (p->loc) == HARD_FRAME_POINTER_REGNUM
+ || REGNO (p->loc) == cfa_base_preserved_regno))
+ return p->loc;
+ /* 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_CSELIB))
+ {
+ 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_CSELIB))
+ 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_CSELIB))
+ {
+ 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;
+ unsigned 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
+ || regno == cfa_base_preserved_regno)
+ return orig;
+
+ bitmap_set_bit (evd->regs_active, regno);
+
+ if (dump_file && (dump_flags & TDF_CSELIB))
+ 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_CSELIB))
+ {
+ 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.
+ If X is within a MEM, MEMMODE must be the mode of the MEM. */
+
+rtx
+cselib_subst_to_values (rtx x, enum machine_mode memmode)
{
enum rtx_code code = GET_CODE (x);
const char *fmt = GET_RTX_FORMAT (code);
if (l && l->elt == NULL)
l = l->next;
for (; l; l = l->next)
- if (GET_MODE (l->elt->u.val_rtx) == GET_MODE (x))
- return l->elt->u.val_rtx;
+ if (GET_MODE (l->elt->val_rtx) == GET_MODE (x))
+ return l->elt->val_rtx;
- abort ();
+ gcc_unreachable ();
case MEM:
e = cselib_lookup_mem (x, 0);
+ /* This used to happen for autoincrements, but we deal with them
+ properly now. Remove the if stmt for the next release. */
if (! e)
{
- /* This happens for autoincrements. Assign a value that doesn't
- match any other. */
- e = new_cselib_val (++next_unknown_value, GET_MODE (x));
+ /* Assign a value that doesn't match any other. */
+ e = new_cselib_val (next_uid, GET_MODE (x), x);
}
- return e->u.val_rtx;
+ return e->val_rtx;
+
+ case ENTRY_VALUE:
+ e = cselib_lookup (x, GET_MODE (x), 0, memmode);
+ if (! e)
+ break;
+ return e->val_rtx;
case CONST_DOUBLE:
case CONST_VECTOR:
case CONST_INT:
+ case CONST_FIXED:
return x;
- case POST_INC:
+ case PRE_DEC:
case PRE_INC:
+ gcc_assert (memmode != VOIDmode);
+ i = GET_MODE_SIZE (memmode);
+ if (code == PRE_DEC)
+ i = -i;
+ return cselib_subst_to_values (plus_constant (XEXP (x, 0), i),
+ memmode);
+
+ case PRE_MODIFY:
+ gcc_assert (memmode != VOIDmode);
+ return cselib_subst_to_values (XEXP (x, 1), memmode);
+
case POST_DEC:
- case PRE_DEC:
+ case POST_INC:
case POST_MODIFY:
- case PRE_MODIFY:
- e = new_cselib_val (++next_unknown_value, GET_MODE (x));
- return e->u.val_rtx;
+ gcc_assert (memmode != VOIDmode);
+ return cselib_subst_to_values (XEXP (x, 0), memmode);
default:
break;
{
if (fmt[i] == 'e')
{
- rtx t = cselib_subst_to_values (XEXP (x, i));
+ rtx t = cselib_subst_to_values (XEXP (x, i), memmode);
- if (t != XEXP (x, i) && x == copy)
- copy = shallow_copy_rtx (x);
-
- XEXP (copy, i) = t;
+ if (t != XEXP (x, i))
+ {
+ if (x == copy)
+ copy = shallow_copy_rtx (x);
+ XEXP (copy, i) = t;
+ }
}
else if (fmt[i] == 'E')
{
- int j, k;
+ int j;
for (j = 0; j < XVECLEN (x, i); j++)
{
- rtx t = cselib_subst_to_values (XVECEXP (x, i, j));
+ rtx t = cselib_subst_to_values (XVECEXP (x, i, j), memmode);
- if (t != XVECEXP (x, i, j) && XVEC (x, i) == XVEC (copy, i))
+ if (t != XVECEXP (x, i, j))
{
- if (x == copy)
- copy = shallow_copy_rtx (x);
-
- XVEC (copy, i) = rtvec_alloc (XVECLEN (x, i));
- for (k = 0; k < j; k++)
- XVECEXP (copy, i, k) = XVECEXP (x, i, k);
+ 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;
}
-
- 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). */
+/* Wrapper for cselib_subst_to_values, that indicates X is in INSN. */
-cselib_val *
-cselib_lookup (rtx x, enum machine_mode mode, int create)
+rtx
+cselib_subst_to_values_from_insn (rtx x, enum machine_mode memmode, rtx insn)
+{
+ rtx ret;
+ gcc_assert (!cselib_current_insn);
+ cselib_current_insn = insn;
+ ret = cselib_subst_to_values (x, memmode);
+ cselib_current_insn = NULL;
+ return ret;
+}
+
+/* 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). When X is part
+ of an address, MEMMODE should be the mode of the enclosing MEM if
+ we're tracking autoinc expressions. */
+
+static cselib_val *
+cselib_lookup_1 (rtx x, enum machine_mode mode,
+ int create, enum machine_mode memmode)
{
void **slot;
cselib_val *e;
if (GET_CODE (x) == VALUE)
return CSELIB_VAL_PTR (x);
- if (GET_CODE (x) == REG)
+ if (REG_P (x))
{
struct elt_list *l;
unsigned int i = REGNO (x);
if (l && l->elt == NULL)
l = l->next;
for (; l; l = l->next)
- if (mode == GET_MODE (l->elt->u.val_rtx))
- return l->elt;
+ if (mode == GET_MODE (l->elt->val_rtx))
+ {
+ promote_debug_loc (l->elt->locs);
+ return l->elt;
+ }
if (! create)
return 0;
max_value_regs = n;
}
- e = new_cselib_val (++next_unknown_value, GET_MODE (x));
- e->locs = new_elt_loc_list (e->locs, x);
+ e = new_cselib_val (next_uid, GET_MODE (x), x);
+ new_elt_loc_list (e, x);
if (REG_VALUES (i) == 0)
{
/* Maintain the invariant that the first entry of
used_regs[n_used_regs++] = i;
REG_VALUES (i) = new_elt_list (REG_VALUES (i), NULL);
}
+ else if (cselib_preserve_constants
+ && GET_MODE_CLASS (mode) == MODE_INT)
+ {
+ /* During var-tracking, try harder to find equivalences
+ for SUBREGs. If a setter sets say a DImode register
+ and user uses that register only in SImode, add a lowpart
+ subreg location. */
+ struct elt_list *lwider = NULL;
+ l = REG_VALUES (i);
+ if (l && l->elt == NULL)
+ l = l->next;
+ for (; l; l = l->next)
+ if (GET_MODE_CLASS (GET_MODE (l->elt->val_rtx)) == MODE_INT
+ && GET_MODE_SIZE (GET_MODE (l->elt->val_rtx))
+ > GET_MODE_SIZE (mode)
+ && (lwider == NULL
+ || GET_MODE_SIZE (GET_MODE (l->elt->val_rtx))
+ < GET_MODE_SIZE (GET_MODE (lwider->elt->val_rtx))))
+ {
+ struct elt_loc_list *el;
+ if (i < FIRST_PSEUDO_REGISTER
+ && hard_regno_nregs[i][GET_MODE (l->elt->val_rtx)] != 1)
+ continue;
+ for (el = l->elt->locs; el; el = el->next)
+ if (!REG_P (el->loc))
+ break;
+ if (el)
+ lwider = l;
+ }
+ if (lwider)
+ {
+ rtx sub = lowpart_subreg (mode, lwider->elt->val_rtx,
+ GET_MODE (lwider->elt->val_rtx));
+ if (sub)
+ new_elt_loc_list (e, sub);
+ }
+ }
REG_VALUES (i)->next = new_elt_list (REG_VALUES (i)->next, e);
- slot = htab_find_slot_with_hash (hash_table, x, e->value, INSERT);
+ slot = cselib_find_slot (x, e->hash, INSERT, memmode);
*slot = e;
return e;
}
- if (GET_CODE (x) == MEM)
+ if (MEM_P (x))
return cselib_lookup_mem (x, create);
- hashval = hash_rtx (x, mode, create);
+ hashval = cselib_hash_rtx (x, create, memmode);
/* Can't even create if hashing is not possible. */
if (! hashval)
return 0;
- slot = htab_find_slot_with_hash (hash_table, wrap_constant (mode, x),
- hashval, create ? INSERT : NO_INSERT);
+ slot = cselib_find_slot (wrap_constant (mode, x), hashval,
+ create ? INSERT : NO_INSERT, memmode);
if (slot == 0)
return 0;
if (e)
return e;
- e = new_cselib_val (hashval, mode);
+ 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));
+ new_elt_loc_list (e, cselib_subst_to_values (x, memmode));
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, enum machine_mode memmode, rtx insn)
+{
+ cselib_val *ret;
+
+ gcc_assert (!cselib_current_insn);
+ cselib_current_insn = insn;
+
+ ret = cselib_lookup (x, mode, create, memmode);
+
+ 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, enum machine_mode memmode)
+{
+ cselib_val *ret = cselib_lookup_1 (x, mode, create, memmode);
+
+ /* ??? 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_CSELIB))
+ {
+ 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
unsigned int i;
/* If we see pseudos after reload, something is _wrong_. */
- if (reload_completed && regno >= FIRST_PSEUDO_REGISTER
- && reg_renumber[regno] >= 0)
- abort ();
+ 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
if they contain values that overlap REGNO. */
if (regno < FIRST_PSEUDO_REGISTER)
{
- if (mode == VOIDmode)
- abort ();
+ gcc_assert (mode != VOIDmode);
if (regno < max_value_regs)
i = 0;
else
i = regno - max_value_regs;
- endregno = regno + hard_regno_nregs[regno][mode];
+ endregno = end_hard_regno (mode, regno);
}
else
{
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 += hard_regno_nregs[i][GET_MODE (v->u.val_rtx)] - 1;
+ this_last = end_hard_regno (GET_MODE (v->val_rtx), i) - 1;
- if (this_last < regno || v == NULL)
+ if (this_last < regno || v == NULL
+ || (v == cfa_base_preserved_val
+ && i == cfa_base_preserved_regno))
{
l = &(*l)->next;
continue;
else
unchain_one_elt_list (l);
+ v = canonical_cselib_val (v);
+
+ 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 (GET_CODE (x) == REG && REGNO (x) == i)
+ if (REG_P (x) && REGNO (x) == i)
{
unchain_one_elt_loc_list (p);
break;
}
}
- if (v->locs == 0)
- n_useless_values++;
+
+ 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++;
+ }
}
}
}
\f
-/* 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 int
-cselib_rtx_varies_p (rtx x ATTRIBUTE_UNUSED, int 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). */
{
bool has_mem = false;
struct elt_loc_list **p = &v->locs;
- int had_locs = v->locs != 0;
+ bool had_locs = v->locs != NULL;
+ rtx setting_insn = v->locs ? v->locs->setting_insn : NULL;
while (*p)
{
rtx x = (*p)->loc;
- rtx canon_x = (*p)->canon_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 (GET_CODE (x) != MEM)
+ if (!MEM_P (x))
{
p = &(*p)->next;
continue;
}
- if (!canon_x)
- canon_x = (*p)->canon_loc = canon_rtx (x);
if (num_mems < PARAM_VALUE (PARAM_MAX_CSELIB_MEMORY_LOCATIONS)
- && ! canon_true_dependence (mem_rtx, GET_MODE (mem_rtx), mem_addr,
- x, cselib_rtx_varies_p))
+ && ! canon_true_dependence (mem_rtx, GET_MODE (mem_rtx),
+ mem_addr, x, NULL_RTX))
{
has_mem = true;
num_mems++;
/* 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);
+ addr = cselib_lookup (XEXP (x, 0), VOIDmode, 0, GET_MODE (x));
+ addr = canonical_cselib_val (addr);
+ gcc_checking_assert (v == canonical_cselib_val (v));
mem_chain = &addr->addr_list;
for (;;)
{
- if ((*mem_chain)->elt == v)
+ cselib_val *canon = canonical_cselib_val ((*mem_chain)->elt);
+
+ if (canon == v)
{
unchain_one_elt_list (mem_chain);
break;
}
+ /* Record canonicalized elt. */
+ (*mem_chain)->elt = canon;
+
mem_chain = &(*mem_chain)->next;
}
unchain_one_elt_loc_list (p);
}
- if (had_locs && v->locs == 0)
- n_useless_values++;
+ 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 = &dummy_val;
}
-/* Invalidate DEST, which is being assigned to or clobbered. The second and
- the third parameter exist so that this function can be passed to
- note_stores; they are ignored. */
+/* Invalidate DEST, which is being assigned to or clobbered. */
-static void
-cselib_invalidate_rtx (rtx dest, rtx ignore ATTRIBUTE_UNUSED,
- void *data ATTRIBUTE_UNUSED)
+void
+cselib_invalidate_rtx (rtx dest)
{
- while (GET_CODE (dest) == STRICT_LOW_PART || GET_CODE (dest) == SIGN_EXTRACT
- || GET_CODE (dest) == ZERO_EXTRACT || GET_CODE (dest) == SUBREG)
+ while (GET_CODE (dest) == SUBREG
+ || GET_CODE (dest) == ZERO_EXTRACT
+ || GET_CODE (dest) == STRICT_LOW_PART)
dest = XEXP (dest, 0);
- if (GET_CODE (dest) == REG)
+ if (REG_P (dest))
cselib_invalidate_regno (REGNO (dest), GET_MODE (dest));
- else if (GET_CODE (dest) == MEM)
+ 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, NULL_RTX, NULL);
+/* 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
static void
cselib_record_set (rtx dest, cselib_val *src_elt, cselib_val *dest_addr_elt)
{
- int dreg = GET_CODE (dest) == REG ? (int) REGNO (dest) : -1;
+ int dreg = REG_P (dest) ? (int) REGNO (dest) : -1;
if (src_elt == 0 || side_effects_p (dest))
return;
}
else
{
- if (REG_VALUES (dreg)->elt == 0)
- REG_VALUES (dreg)->elt = src_elt;
- else
- /* The register should have been invalidated. */
- abort ();
+ /* The register should have been invalidated. */
+ gcc_assert (REG_VALUES (dreg)->elt == 0);
+ REG_VALUES (dreg)->elt = src_elt;
}
- if (src_elt->locs == 0)
+ 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);
+ new_elt_loc_list (src_elt, dest);
}
- else if (GET_CODE (dest) == MEM && dest_addr_elt != 0)
+ else if (MEM_P (dest) && dest_addr_elt != 0
+ && cselib_record_memory)
{
- if (src_elt->locs == 0)
+ 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);
}
}
-/* Describe a single set that is part of an insn. */
-struct set
+/* Make ELT and X's VALUE equivalent to each other at INSN. */
+
+void
+cselib_add_permanent_equiv (cselib_val *elt, rtx x, rtx insn)
{
- rtx src;
- rtx dest;
- cselib_val *src_elt;
- cselib_val *dest_addr_elt;
-};
+ cselib_val *nelt;
+ rtx save_cselib_current_insn = cselib_current_insn;
+
+ gcc_checking_assert (elt);
+ gcc_checking_assert (PRESERVED_VALUE_P (elt->val_rtx));
+ gcc_checking_assert (!side_effects_p (x));
+
+ cselib_current_insn = insn;
+
+ nelt = cselib_lookup (x, GET_MODE (elt->val_rtx), 1, VOIDmode);
+
+ if (nelt != elt)
+ {
+ if (!PRESERVED_VALUE_P (nelt->val_rtx))
+ cselib_preserve_value (nelt);
+
+ new_elt_loc_list (nelt, elt->val_rtx);
+ }
+
+ cselib_current_insn = save_cselib_current_insn;
+}
/* 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. */
+struct cselib_record_autoinc_data
+{
+ struct cselib_set *sets;
+ int n_sets;
+};
+
+/* Callback for for_each_inc_dec. Records in ARG the SETs implied by
+ autoinc RTXs: SRC plus SRCOFF if non-NULL is stored in DEST. */
+
+static int
+cselib_record_autoinc_cb (rtx mem ATTRIBUTE_UNUSED, rtx op ATTRIBUTE_UNUSED,
+ rtx dest, rtx src, rtx srcoff, void *arg)
+{
+ struct cselib_record_autoinc_data *data;
+ data = (struct cselib_record_autoinc_data *)arg;
+
+ data->sets[data->n_sets].dest = dest;
+
+ if (srcoff)
+ data->sets[data->n_sets].src = gen_rtx_PLUS (GET_MODE (src), src, srcoff);
+ else
+ data->sets[data->n_sets].src = src;
+
+ data->n_sets++;
+
+ return -1;
+}
+
+/* Record the effects of any sets and autoincs in INSN. */
static void
cselib_record_sets (rtx insn)
{
int n_sets = 0;
int i;
- struct set sets[MAX_SETS];
+ struct cselib_set sets[MAX_SETS];
rtx body = PATTERN (insn);
rtx cond = 0;
+ int n_sets_before_autoinc;
+ struct cselib_record_autoinc_data data;
body = PATTERN (insn);
if (GET_CODE (body) == COND_EXEC)
}
}
+ 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);
+ }
+
+ data.sets = sets;
+ data.n_sets = n_sets_before_autoinc = n_sets;
+ for_each_inc_dec (&insn, cselib_record_autoinc_cb, &data);
+ n_sets = data.n_sets;
+
/* Look up the values that are read. Do this before invalidating the
locations that are written. */
for (i = 0; i < n_sets; i++)
sets[i].dest = dest = XEXP (dest, 0);
/* We don't know how to record anything but REG or MEM. */
- if (GET_CODE (dest) == REG || GET_CODE (dest) == 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 (src), cond, src, dest);
- sets[i].src_elt = cselib_lookup (src, GET_MODE (dest), 1);
- if (GET_CODE (dest) == MEM)
- sets[i].dest_addr_elt = cselib_lookup (XEXP (dest, 0), Pmode, 1);
+ src = gen_rtx_IF_THEN_ELSE (GET_MODE (dest), cond, src, dest);
+ sets[i].src_elt = cselib_lookup (src, GET_MODE (dest), 1, VOIDmode);
+ 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,
+ GET_MODE (dest));
+ }
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, NULL);
+ note_stores (body, cselib_invalidate_rtx_note_stores, NULL);
+
+ for (i = n_sets_before_autoinc; i < n_sets; i++)
+ cselib_invalidate_rtx (sets[i].dest);
/* 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
for (i = 0; i < n_sets; i++)
{
rtx dest = sets[i].dest;
- if (GET_CODE (dest) == REG || GET_CODE (dest) == MEM)
+ if (REG_P (dest) || MEM_P (dest))
{
int j;
for (j = i + 1; j < n_sets; j++)
for (i = 0; i < n_sets; i++)
{
rtx dest = sets[i].dest;
- if (GET_CODE (dest) == REG || GET_CODE (dest) == MEM)
+ if (REG_P (dest)
+ || (MEM_P (dest) && cselib_record_memory))
cselib_record_set (dest, sets[i].src_elt, sets[i].dest_addr_elt);
}
}
int i;
rtx x;
- if (find_reg_note (insn, REG_LIBCALL, NULL))
- cselib_current_insn_in_libcall = true;
- if (find_reg_note (insn, REG_RETVAL, NULL))
- cselib_current_insn_in_libcall = false;
cselib_current_insn = insn;
/* Forget everything at a CODE_LABEL, a volatile asm, or a setjmp. */
- if (GET_CODE (insn) == CODE_LABEL
- || (GET_CODE (insn) == CALL_INSN
+ if (LABEL_P (insn)
+ || (CALL_P (insn)
&& find_reg_note (insn, REG_SETJMP, NULL))
- || (GET_CODE (insn) == INSN
+ || (NONJUMP_INSN_P (insn)
&& GET_CODE (PATTERN (insn)) == ASM_OPERANDS
&& MEM_VOLATILE_P (PATTERN (insn))))
{
- clear_table ();
+ cselib_reset_table (next_uid);
+ cselib_current_insn = NULL_RTX;
return;
}
if (! INSN_P (insn))
{
- cselib_current_insn = 0;
+ 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 (GET_CODE (insn) == CALL_INSN)
+ if (CALL_P (insn))
{
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- if (call_used_regs[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]);
- if (! CONST_OR_PURE_CALL_P (insn))
+ /* 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), NULL_RTX, NULL);
-#endif
-
/* Look for any CLOBBERs in CALL_INSN_FUNCTION_USAGE, but only
after we have processed the insn. */
- if (GET_CODE (insn) == CALL_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), NULL_RTX, NULL);
-
- cselib_current_insn = 0;
-
- if (n_useless_values > MAX_USELESS_VALUES)
+ 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 ();
}
init_alias_analysis. */
void
-cselib_init (void)
+cselib_init (int record_what)
{
- elt_list_pool = create_alloc_pool ("elt_list",
+ elt_list_pool = create_alloc_pool ("elt_list",
sizeof (struct elt_list), 10);
- elt_loc_list_pool = create_alloc_pool ("elt_loc_list",
+ 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",
+ cselib_val_pool = create_alloc_pool ("cselib_val_list",
sizeof (cselib_val), 10);
- value_pool = create_alloc_pool ("value",
- RTX_SIZE (VALUE), 100);
- /* This is only created once. */
+ 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, const0_rtx);
+ callmem = gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (VOIDmode));
cselib_nregs = max_reg_num ();
if (!reg_values || reg_values_size < cselib_nregs
|| (reg_values_size > 10 && reg_values_size > cselib_nregs * 4))
{
- if (reg_values)
- free (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 = xcalloc (reg_values_size, sizeof (reg_values));
+ reg_values = XCNEWVEC (struct elt_list *, reg_values_size);
}
- used_regs = xmalloc (sizeof (*used_regs) * cselib_nregs);
+ used_regs = XNEWVEC (unsigned int, cselib_nregs);
n_used_regs = 0;
- hash_table = htab_create (31, get_value_hash, entry_and_rtx_equal_p, NULL);
- cselib_current_insn_in_libcall = false;
+ 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;
+ cfa_base_preserved_regno = INVALID_REGNUM;
free_alloc_pool (elt_list_pool);
free_alloc_pool (elt_loc_list_pool);
free_alloc_pool (cselib_val_pool);
free_alloc_pool (value_pool);
- clear_table ();
- htab_delete (hash_table);
+ cselib_clear_table ();
+ htab_delete (cselib_hash_table);
free (used_regs);
used_regs = 0;
- hash_table = 0;
+ cselib_hash_table = 0;
n_useless_values = 0;
- next_unknown_value = 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
+ {
+ if (l->setting_insn)
+ fprintf (out, "\n from insn %i ",
+ INSN_UID (l->setting_insn));
+ else
+ fprintf (out, "\n ");
+ 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"
OSDN Git Service
