gcc/gcc/tree-data-ref.h
Daniel Berlin 14b33c04a1 tree-data-ref.c (analyze_array_indexes): Add estimate_only parameter.
2005-09-15  Daniel Berlin  <dberlin@dberlin.org>

	* tree-data-ref.c (analyze_array_indexes): Add estimate_only
	parameter.
	Update callers.
	(estimate_iters_using_array): New function.
	* tree-data-ref.h (estimate_iters_using_array): Prototype
	* tree-ssa-loop-niter.c (infer_loop_bounds_from_undefined):
	Use estimate_iters_using_array instead of analyze_array.

From-SVN: r104312
2005-09-15 17:21:48 +00:00

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/* Data references and dependences detectors.
Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
Contributed by Sebastian Pop <s.pop@laposte.net>
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
version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING. If not, write to the Free
Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301, USA. */
#ifndef GCC_TREE_DATA_REF_H
#define GCC_TREE_DATA_REF_H
#include "lambda.h"
/** {base_address + offset + init} is the first location accessed by data-ref
in the loop, and step is the stride of data-ref in the loop in bytes;
e.g.:
Example 1 Example 2
data-ref a[j].b[i][j] a + x + 16B (a is int*)
First location info:
base_address &a a
offset j_0*D_j + i_0*D_i + C_a x
init C_b 16
step D_j 4
access_fn NULL {16, +, 1}
Base object info:
base_object a NULL
access_fn <access_fns of indexes of b> NULL
**/
struct first_location_in_loop
{
tree base_address;
tree offset;
tree init;
tree step;
/* Access function related to first location in the loop. */
VEC(tree,heap) *access_fns;
};
struct base_object_info
{
/* The object. */
tree base_object;
/* A list of chrecs. Access functions related to BASE_OBJECT. */
VEC(tree,heap) *access_fns;
};
enum data_ref_type {
ARRAY_REF_TYPE,
POINTER_REF_TYPE
};
struct data_reference
{
/* A pointer to the statement that contains this DR. */
tree stmt;
/* A pointer to the ARRAY_REF node. */
tree ref;
/* Auxiliary info specific to a pass. */
int aux;
/* True when the data reference is in RHS of a stmt. */
bool is_read;
/* First location accessed by the data-ref in the loop. */
struct first_location_in_loop first_location;
/* Base object related info. */
struct base_object_info object_info;
/* Aliasing information. This field represents the symbol that
should be aliased by a pointer holding the address of this data
reference. If the original data reference was a pointer
dereference, then this field contains the memory tag that should
be used by the new vector-pointer. */
tree memtag;
struct ptr_info_def *ptr_info;
subvar_t subvars;
/* Alignment information. */
/* The offset of the data-reference from its base in bytes. */
tree misalignment;
/* The maximum data-ref's alignment. */
tree aligned_to;
/* The type of the data-ref. */
enum data_ref_type type;
};
#define DR_STMT(DR) (DR)->stmt
#define DR_REF(DR) (DR)->ref
#define DR_BASE_OBJECT(DR) (DR)->object_info.base_object
#define DR_TYPE(DR) (DR)->type
#define DR_ACCESS_FNS(DR)\
(DR_TYPE(DR) == ARRAY_REF_TYPE ? \
(DR)->object_info.access_fns : (DR)->first_location.access_fns)
#define DR_ACCESS_FN(DR, I) VEC_index (tree, DR_ACCESS_FNS (DR), I)
#define DR_NUM_DIMENSIONS(DR) VEC_length (tree, DR_ACCESS_FNS (DR))
#define DR_IS_READ(DR) (DR)->is_read
#define DR_BASE_ADDRESS(DR) (DR)->first_location.base_address
#define DR_OFFSET(DR) (DR)->first_location.offset
#define DR_INIT(DR) (DR)->first_location.init
#define DR_STEP(DR) (DR)->first_location.step
#define DR_MEMTAG(DR) (DR)->memtag
#define DR_ALIGNED_TO(DR) (DR)->aligned_to
#define DR_OFFSET_MISALIGNMENT(DR) (DR)->misalignment
#define DR_PTR_INFO(DR) (DR)->ptr_info
#define DR_SUBVARS(DR) (DR)->subvars
#define DR_ACCESS_FNS_ADDR(DR) \
(DR_TYPE(DR) == ARRAY_REF_TYPE ? \
&((DR)->object_info.access_fns) : &((DR)->first_location.access_fns))
#define DR_SET_ACCESS_FNS(DR, ACC_FNS) \
{ \
if (DR_TYPE(DR) == ARRAY_REF_TYPE) \
(DR)->object_info.access_fns = ACC_FNS; \
else \
(DR)->first_location.access_fns = ACC_FNS; \
}
#define DR_FREE_ACCESS_FNS(DR) \
{ \
if (DR_TYPE(DR) == ARRAY_REF_TYPE) \
VEC_free (tree, heap, (DR)->object_info.access_fns); \
else \
VEC_free (tree, heap, (DR)->first_location.access_fns); \
}
enum data_dependence_direction {
dir_positive,
dir_negative,
dir_equal,
dir_positive_or_negative,
dir_positive_or_equal,
dir_negative_or_equal,
dir_star,
dir_independent
};
/* What is a subscript? Given two array accesses a subscript is the
tuple composed of the access functions for a given dimension.
Example: Given A[f1][f2][f3] and B[g1][g2][g3], there are three
subscripts: (f1, g1), (f2, g2), (f3, g3). These three subscripts
are stored in the data_dependence_relation structure under the form
of an array of subscripts. */
struct subscript
{
/* A description of the iterations for which the elements are
accessed twice. */
tree conflicting_iterations_in_a;
tree conflicting_iterations_in_b;
/* This field stores the information about the iteration domain
validity of the dependence relation. */
tree last_conflict;
/* Distance from the iteration that access a conflicting element in
A to the iteration that access this same conflicting element in
B. The distance is a tree scalar expression, i.e. a constant or a
symbolic expression, but certainly not a chrec function. */
tree distance;
};
#define SUB_CONFLICTS_IN_A(SUB) SUB->conflicting_iterations_in_a
#define SUB_CONFLICTS_IN_B(SUB) SUB->conflicting_iterations_in_b
#define SUB_LAST_CONFLICT(SUB) SUB->last_conflict
#define SUB_DISTANCE(SUB) SUB->distance
/* A data_dependence_relation represents a relation between two
data_references A and B. */
struct data_dependence_relation
{
struct data_reference *a;
struct data_reference *b;
/* When the dependence relation is affine, it can be represented by
a distance vector. */
bool affine_p;
/* A "yes/no/maybe" field for the dependence relation:
- when "ARE_DEPENDENT == NULL_TREE", there exist a dependence
relation between A and B, and the description of this relation
is given in the SUBSCRIPTS array,
- when "ARE_DEPENDENT == chrec_known", there is no dependence and
SUBSCRIPTS is empty,
- when "ARE_DEPENDENT == chrec_dont_know", there may be a dependence,
but the analyzer cannot be more specific. */
tree are_dependent;
/* For each subscript in the dependence test, there is an element in
this array. This is the attribute that labels the edge A->B of
the data_dependence_relation. */
varray_type subscripts;
/* The size of the direction/distance vectors. */
int size_vect;
/* The classic direction vector. */
lambda_vector dir_vect;
/* The classic distance vector. */
lambda_vector dist_vect;
};
#define DDR_A(DDR) DDR->a
#define DDR_B(DDR) DDR->b
#define DDR_AFFINE_P(DDR) DDR->affine_p
#define DDR_ARE_DEPENDENT(DDR) DDR->are_dependent
#define DDR_SUBSCRIPTS(DDR) DDR->subscripts
#define DDR_SUBSCRIPTS_VECTOR_INIT(DDR, N) \
VARRAY_GENERIC_PTR_INIT (DDR_SUBSCRIPTS (DDR), N, "subscripts_vector");
#define DDR_SUBSCRIPT(DDR, I) VARRAY_GENERIC_PTR (DDR_SUBSCRIPTS (DDR), I)
#define DDR_NUM_SUBSCRIPTS(DDR) VARRAY_ACTIVE_SIZE (DDR_SUBSCRIPTS (DDR))
#define DDR_SIZE_VECT(DDR) DDR->size_vect
#define DDR_DIR_VECT(DDR) DDR->dir_vect
#define DDR_DIST_VECT(DDR) DDR->dist_vect
extern tree find_data_references_in_loop (struct loop *, varray_type *);
extern struct data_dependence_relation *initialize_data_dependence_relation
(struct data_reference *, struct data_reference *);
extern void compute_affine_dependence (struct data_dependence_relation *);
extern void analyze_all_data_dependences (struct loops *);
extern void compute_data_dependences_for_loop (struct loop *, bool,
varray_type *, varray_type *);
extern void dump_subscript (FILE *, struct subscript *);
extern void dump_ddrs (FILE *, varray_type);
extern void dump_dist_dir_vectors (FILE *, varray_type);
extern void dump_data_reference (FILE *, struct data_reference *);
extern void dump_data_references (FILE *, varray_type);
extern void dump_data_dependence_relation (FILE *,
struct data_dependence_relation *);
extern void dump_data_dependence_relations (FILE *, varray_type);
extern void dump_data_dependence_direction (FILE *,
enum data_dependence_direction);
extern void free_dependence_relation (struct data_dependence_relation *);
extern void free_dependence_relations (varray_type);
extern void free_data_refs (varray_type);
extern void compute_subscript_distance (struct data_dependence_relation *);
extern struct data_reference *analyze_array (tree, tree, bool);
extern void estimate_iters_using_array (tree, tree);
#endif /* GCC_TREE_DATA_REF_H */