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Diffstat (limited to 'gcc-4.2.1-5666.3/gcc/tree-data-ref.c')
-rw-r--r-- | gcc-4.2.1-5666.3/gcc/tree-data-ref.c | 4495 |
1 files changed, 0 insertions, 4495 deletions
diff --git a/gcc-4.2.1-5666.3/gcc/tree-data-ref.c b/gcc-4.2.1-5666.3/gcc/tree-data-ref.c deleted file mode 100644 index 75b57392a..000000000 --- a/gcc-4.2.1-5666.3/gcc/tree-data-ref.c +++ /dev/null @@ -1,4495 +0,0 @@ - -/* Data references and dependences detectors. - Copyright (C) 2003, 2004, 2005, 2006 Free Software Foundation, Inc. - Contributed by Sebastian Pop <pop@cri.ensmp.fr> - -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. */ - -/* This pass walks a given loop structure searching for array - references. The information about the array accesses is recorded - in DATA_REFERENCE structures. - - The basic test for determining the dependences is: - given two access functions chrec1 and chrec2 to a same array, and - x and y two vectors from the iteration domain, the same element of - the array is accessed twice at iterations x and y if and only if: - | chrec1 (x) == chrec2 (y). - - The goals of this analysis are: - - - to determine the independence: the relation between two - independent accesses is qualified with the chrec_known (this - information allows a loop parallelization), - - - when two data references access the same data, to qualify the - dependence relation with classic dependence representations: - - - distance vectors - - direction vectors - - loop carried level dependence - - polyhedron dependence - or with the chains of recurrences based representation, - - - to define a knowledge base for storing the data dependence - information, - - - to define an interface to access this data. - - - Definitions: - - - 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). - - - Diophantine equation: an equation whose coefficients and - solutions are integer constants, for example the equation - | 3*x + 2*y = 1 - has an integer solution x = 1 and y = -1. - - References: - - - "Advanced Compilation for High Performance Computing" by Randy - Allen and Ken Kennedy. - http://citeseer.ist.psu.edu/goff91practical.html - - - "Loop Transformations for Restructuring Compilers - The Foundations" - by Utpal Banerjee. - - -*/ - -#include "config.h" -#include "system.h" -#include "coretypes.h" -#include "tm.h" -#include "ggc.h" -#include "tree.h" - -/* These RTL headers are needed for basic-block.h. */ -#include "rtl.h" -#include "basic-block.h" -#include "diagnostic.h" -#include "tree-flow.h" -#include "tree-dump.h" -#include "timevar.h" -#include "cfgloop.h" -#include "tree-chrec.h" -#include "tree-data-ref.h" -#include "tree-scalar-evolution.h" -#include "tree-pass.h" - -static struct datadep_stats -{ - int num_dependence_tests; - int num_dependence_dependent; - int num_dependence_independent; - int num_dependence_undetermined; - - int num_subscript_tests; - int num_subscript_undetermined; - int num_same_subscript_function; - - int num_ziv; - int num_ziv_independent; - int num_ziv_dependent; - int num_ziv_unimplemented; - - int num_siv; - int num_siv_independent; - int num_siv_dependent; - int num_siv_unimplemented; - - int num_miv; - int num_miv_independent; - int num_miv_dependent; - int num_miv_unimplemented; -} dependence_stats; - -static tree object_analysis (tree, tree, bool, struct data_reference **, - tree *, tree *, tree *, tree *, tree *, - struct ptr_info_def **, subvar_t *); -static struct data_reference * init_data_ref (tree, tree, tree, tree, bool, - tree, tree, tree, tree, tree, - struct ptr_info_def *, - enum data_ref_type); -static bool subscript_dependence_tester_1 (struct data_dependence_relation *, - struct data_reference *, - struct data_reference *); - -/* Determine if PTR and DECL may alias, the result is put in ALIASED. - Return FALSE if there is no symbol memory tag for PTR. */ - -static bool -ptr_decl_may_alias_p (tree ptr, tree decl, - struct data_reference *ptr_dr, - bool *aliased) -{ - tree tag = NULL_TREE; - struct ptr_info_def *pi = DR_PTR_INFO (ptr_dr); - - gcc_assert (TREE_CODE (ptr) == SSA_NAME && DECL_P (decl)); - - if (pi) - tag = pi->name_mem_tag; - if (!tag) - tag = get_var_ann (SSA_NAME_VAR (ptr))->symbol_mem_tag; - if (!tag) - tag = DR_MEMTAG (ptr_dr); - if (!tag) - return false; - - *aliased = is_aliased_with (tag, decl); - return true; -} - - -/* Determine if two pointers may alias, the result is put in ALIASED. - Return FALSE if there is no symbol memory tag for one of the pointers. */ - -static bool -ptr_ptr_may_alias_p (tree ptr_a, tree ptr_b, - struct data_reference *dra, - struct data_reference *drb, - bool *aliased) -{ - tree tag_a = NULL_TREE, tag_b = NULL_TREE; - struct ptr_info_def *pi_a = DR_PTR_INFO (dra); - struct ptr_info_def *pi_b = DR_PTR_INFO (drb); - - if (pi_a && pi_a->name_mem_tag && pi_b && pi_b->name_mem_tag) - { - tag_a = pi_a->name_mem_tag; - tag_b = pi_b->name_mem_tag; - } - else - { - tag_a = get_var_ann (SSA_NAME_VAR (ptr_a))->symbol_mem_tag; - if (!tag_a) - tag_a = DR_MEMTAG (dra); - if (!tag_a) - return false; - - tag_b = get_var_ann (SSA_NAME_VAR (ptr_b))->symbol_mem_tag; - if (!tag_b) - tag_b = DR_MEMTAG (drb); - if (!tag_b) - return false; - } - - if (tag_a == tag_b) - *aliased = true; - else - *aliased = may_aliases_intersect (tag_a, tag_b); - - return true; -} - - -/* Determine if BASE_A and BASE_B may alias, the result is put in ALIASED. - Return FALSE if there is no symbol memory tag for one of the symbols. */ - -static bool -may_alias_p (tree base_a, tree base_b, - struct data_reference *dra, - struct data_reference *drb, - bool *aliased) -{ - if (TREE_CODE (base_a) == ADDR_EXPR || TREE_CODE (base_b) == ADDR_EXPR) - { - if (TREE_CODE (base_a) == ADDR_EXPR && TREE_CODE (base_b) == ADDR_EXPR) - { - *aliased = (TREE_OPERAND (base_a, 0) == TREE_OPERAND (base_b, 0)); - return true; - } - if (TREE_CODE (base_a) == ADDR_EXPR) - return ptr_decl_may_alias_p (base_b, TREE_OPERAND (base_a, 0), drb, - aliased); - else - return ptr_decl_may_alias_p (base_a, TREE_OPERAND (base_b, 0), dra, - aliased); - } - - return ptr_ptr_may_alias_p (base_a, base_b, dra, drb, aliased); -} - - -/* Determine if a pointer (BASE_A) and a record/union access (BASE_B) - are not aliased. Return TRUE if they differ. */ -static bool -record_ptr_differ_p (struct data_reference *dra, - struct data_reference *drb) -{ - bool aliased; - tree base_a = DR_BASE_OBJECT (dra); - tree base_b = DR_BASE_OBJECT (drb); - - if (TREE_CODE (base_b) != COMPONENT_REF) - return false; - - /* Peel COMPONENT_REFs to get to the base. Do not peel INDIRECT_REFs. - For a.b.c.d[i] we will get a, and for a.b->c.d[i] we will get a.b. - Probably will be unnecessary with struct alias analysis. */ - while (TREE_CODE (base_b) == COMPONENT_REF) - base_b = TREE_OPERAND (base_b, 0); - /* Compare a record/union access (b.c[i] or p->c[i]) and a pointer - ((*q)[i]). */ - if (TREE_CODE (base_a) == INDIRECT_REF - && ((TREE_CODE (base_b) == VAR_DECL - && (ptr_decl_may_alias_p (TREE_OPERAND (base_a, 0), base_b, dra, - &aliased) - && !aliased)) - || (TREE_CODE (base_b) == INDIRECT_REF - && (ptr_ptr_may_alias_p (TREE_OPERAND (base_a, 0), - TREE_OPERAND (base_b, 0), dra, drb, - &aliased) - && !aliased)))) - return true; - else - return false; -} - -/* Determine if two record/union accesses are aliased. Return TRUE if they - differ. */ -static bool -record_record_differ_p (struct data_reference *dra, - struct data_reference *drb) -{ - bool aliased; - tree base_a = DR_BASE_OBJECT (dra); - tree base_b = DR_BASE_OBJECT (drb); - - if (TREE_CODE (base_b) != COMPONENT_REF - || TREE_CODE (base_a) != COMPONENT_REF) - return false; - - /* Peel COMPONENT_REFs to get to the base. Do not peel INDIRECT_REFs. - For a.b.c.d[i] we will get a, and for a.b->c.d[i] we will get a.b. - Probably will be unnecessary with struct alias analysis. */ - while (TREE_CODE (base_b) == COMPONENT_REF) - base_b = TREE_OPERAND (base_b, 0); - while (TREE_CODE (base_a) == COMPONENT_REF) - base_a = TREE_OPERAND (base_a, 0); - - if (TREE_CODE (base_a) == INDIRECT_REF - && TREE_CODE (base_b) == INDIRECT_REF - && ptr_ptr_may_alias_p (TREE_OPERAND (base_a, 0), - TREE_OPERAND (base_b, 0), - dra, drb, &aliased) - && !aliased) - return true; - else - return false; -} - -/* Determine if an array access (BASE_A) and a record/union access (BASE_B) - are not aliased. Return TRUE if they differ. */ -static bool -record_array_differ_p (struct data_reference *dra, - struct data_reference *drb) -{ - bool aliased; - tree base_a = DR_BASE_OBJECT (dra); - tree base_b = DR_BASE_OBJECT (drb); - - if (TREE_CODE (base_b) != COMPONENT_REF) - return false; - - /* Peel COMPONENT_REFs to get to the base. Do not peel INDIRECT_REFs. - For a.b.c.d[i] we will get a, and for a.b->c.d[i] we will get a.b. - Probably will be unnecessary with struct alias analysis. */ - while (TREE_CODE (base_b) == COMPONENT_REF) - base_b = TREE_OPERAND (base_b, 0); - - /* Compare a record/union access (b.c[i] or p->c[i]) and an array access - (a[i]). In case of p->c[i] use alias analysis to verify that p is not - pointing to a. */ - if (TREE_CODE (base_a) == VAR_DECL - && (TREE_CODE (base_b) == VAR_DECL - || (TREE_CODE (base_b) == INDIRECT_REF - && (ptr_decl_may_alias_p (TREE_OPERAND (base_b, 0), base_a, drb, - &aliased) - && !aliased)))) - return true; - else - return false; -} - - -/* Determine if an array access (BASE_A) and a pointer (BASE_B) - are not aliased. Return TRUE if they differ. */ -static bool -array_ptr_differ_p (tree base_a, tree base_b, - struct data_reference *drb) -{ - bool aliased; - - /* In case one of the bases is a pointer (a[i] and (*p)[i]), we check with the - help of alias analysis that p is not pointing to a. */ - if (TREE_CODE (base_a) == VAR_DECL && TREE_CODE (base_b) == INDIRECT_REF - && (ptr_decl_may_alias_p (TREE_OPERAND (base_b, 0), base_a, drb, &aliased) - && !aliased)) - return true; - else - return false; -} - - -/* This is the simplest data dependence test: determines whether the - data references A and B access the same array/region. Returns - false when the property is not computable at compile time. - Otherwise return true, and DIFFER_P will record the result. This - utility will not be necessary when alias_sets_conflict_p will be - less conservative. */ - -static bool -base_object_differ_p (struct data_reference *a, - struct data_reference *b, - bool *differ_p) -{ - tree base_a = DR_BASE_OBJECT (a); - tree base_b = DR_BASE_OBJECT (b); - bool aliased; - - if (!base_a || !base_b) - return false; - - /* Determine if same base. Example: for the array accesses - a[i], b[i] or pointer accesses *a, *b, bases are a, b. */ - if (base_a == base_b) - { - *differ_p = false; - return true; - } - - /* For pointer based accesses, (*p)[i], (*q)[j], the bases are (*p) - and (*q) */ - if (TREE_CODE (base_a) == INDIRECT_REF && TREE_CODE (base_b) == INDIRECT_REF - && TREE_OPERAND (base_a, 0) == TREE_OPERAND (base_b, 0)) - { - *differ_p = false; - return true; - } - - /* Record/union based accesses - s.a[i], t.b[j]. bases are s.a,t.b. */ - if (TREE_CODE (base_a) == COMPONENT_REF && TREE_CODE (base_b) == COMPONENT_REF - && TREE_OPERAND (base_a, 0) == TREE_OPERAND (base_b, 0) - && TREE_OPERAND (base_a, 1) == TREE_OPERAND (base_b, 1)) - { - *differ_p = false; - return true; - } - - - /* Determine if different bases. */ - - /* At this point we know that base_a != base_b. However, pointer - accesses of the form x=(*p) and y=(*q), whose bases are p and q, - may still be pointing to the same base. In SSAed GIMPLE p and q will - be SSA_NAMES in this case. Therefore, here we check if they are - really two different declarations. */ - if (TREE_CODE (base_a) == VAR_DECL && TREE_CODE (base_b) == VAR_DECL) - { - *differ_p = true; - return true; - } - - /* In case one of the bases is a pointer (a[i] and (*p)[i]), we check with the - help of alias analysis that p is not pointing to a. */ - if (array_ptr_differ_p (base_a, base_b, b) - || array_ptr_differ_p (base_b, base_a, a)) - { - *differ_p = true; - return true; - } - - /* If the bases are pointers ((*q)[i] and (*p)[i]), we check with the - help of alias analysis they don't point to the same bases. */ - if (TREE_CODE (base_a) == INDIRECT_REF && TREE_CODE (base_b) == INDIRECT_REF - && (may_alias_p (TREE_OPERAND (base_a, 0), TREE_OPERAND (base_b, 0), a, b, - &aliased) - && !aliased)) - { - *differ_p = true; - return true; - } - - /* Compare two record/union bases s.a and t.b: s != t or (a != b and - s and t are not unions). */ - if (TREE_CODE (base_a) == COMPONENT_REF && TREE_CODE (base_b) == COMPONENT_REF - && ((TREE_CODE (TREE_OPERAND (base_a, 0)) == VAR_DECL - && TREE_CODE (TREE_OPERAND (base_b, 0)) == VAR_DECL - && TREE_OPERAND (base_a, 0) != TREE_OPERAND (base_b, 0)) - || (TREE_CODE (TREE_TYPE (TREE_OPERAND (base_a, 0))) == RECORD_TYPE - && TREE_CODE (TREE_TYPE (TREE_OPERAND (base_b, 0))) == RECORD_TYPE - && TREE_OPERAND (base_a, 1) != TREE_OPERAND (base_b, 1)))) - { - *differ_p = true; - return true; - } - - /* Compare a record/union access (b.c[i] or p->c[i]) and a pointer - ((*q)[i]). */ - if (record_ptr_differ_p (a, b) || record_ptr_differ_p (b, a)) - { - *differ_p = true; - return true; - } - - /* Compare a record/union access (b.c[i] or p->c[i]) and an array access - (a[i]). In case of p->c[i] use alias analysis to verify that p is not - pointing to a. */ - if (record_array_differ_p (a, b) || record_array_differ_p (b, a)) - { - *differ_p = true; - return true; - } - - /* Compare two record/union accesses (b.c[i] or p->c[i]). */ - if (record_record_differ_p (a, b)) - { - *differ_p = true; - return true; - } - - return false; -} - -/* Function base_addr_differ_p. - - This is the simplest data dependence test: determines whether the - data references DRA and DRB access the same array/region. Returns - false when the property is not computable at compile time. - Otherwise return true, and DIFFER_P will record the result. - - The algorithm: - 1. if (both DRA and DRB are represented as arrays) - compare DRA.BASE_OBJECT and DRB.BASE_OBJECT - 2. else if (both DRA and DRB are represented as pointers) - try to prove that DRA.FIRST_LOCATION == DRB.FIRST_LOCATION - 3. else if (DRA and DRB are represented differently or 2. fails) - only try to prove that the bases are surely different -*/ - -static bool -base_addr_differ_p (struct data_reference *dra, - struct data_reference *drb, - bool *differ_p) -{ - tree addr_a = DR_BASE_ADDRESS (dra); - tree addr_b = DR_BASE_ADDRESS (drb); - tree type_a, type_b; - bool aliased; - - if (!addr_a || !addr_b) - return false; - - type_a = TREE_TYPE (addr_a); - type_b = TREE_TYPE (addr_b); - - gcc_assert (POINTER_TYPE_P (type_a) && POINTER_TYPE_P (type_b)); - - /* 1. if (both DRA and DRB are represented as arrays) - compare DRA.BASE_OBJECT and DRB.BASE_OBJECT. */ - if (DR_TYPE (dra) == ARRAY_REF_TYPE && DR_TYPE (drb) == ARRAY_REF_TYPE) - return base_object_differ_p (dra, drb, differ_p); - - /* 2. else if (both DRA and DRB are represented as pointers) - try to prove that DRA.FIRST_LOCATION == DRB.FIRST_LOCATION. */ - /* If base addresses are the same, we check the offsets, since the access of - the data-ref is described by {base addr + offset} and its access function, - i.e., in order to decide whether the bases of data-refs are the same we - compare both base addresses and offsets. */ - if (DR_TYPE (dra) == POINTER_REF_TYPE && DR_TYPE (drb) == POINTER_REF_TYPE - && (addr_a == addr_b - || (TREE_CODE (addr_a) == ADDR_EXPR && TREE_CODE (addr_b) == ADDR_EXPR - && TREE_OPERAND (addr_a, 0) == TREE_OPERAND (addr_b, 0)))) - { - /* Compare offsets. */ - tree offset_a = DR_OFFSET (dra); - tree offset_b = DR_OFFSET (drb); - - STRIP_NOPS (offset_a); - STRIP_NOPS (offset_b); - - /* FORNOW: we only compare offsets that are MULT_EXPR, i.e., we don't handle - PLUS_EXPR. */ - if (offset_a == offset_b - || (TREE_CODE (offset_a) == MULT_EXPR - && TREE_CODE (offset_b) == MULT_EXPR - && TREE_OPERAND (offset_a, 0) == TREE_OPERAND (offset_b, 0) - && TREE_OPERAND (offset_a, 1) == TREE_OPERAND (offset_b, 1))) - { - *differ_p = false; - return true; - } - } - - /* 3. else if (DRA and DRB are represented differently or 2. fails) - only try to prove that the bases are surely different. */ - - /* Apply alias analysis. */ - if (may_alias_p (addr_a, addr_b, dra, drb, &aliased) && !aliased) - { - *differ_p = true; - return true; - } - - /* An instruction writing through a restricted pointer is "independent" of any - instruction reading or writing through a different pointer, in the same - block/scope. */ - else if ((TYPE_RESTRICT (type_a) && !DR_IS_READ (dra)) - || (TYPE_RESTRICT (type_b) && !DR_IS_READ (drb))) - { - *differ_p = true; - return true; - } - return false; -} - -/* Returns true iff A divides B. */ - -static inline bool -tree_fold_divides_p (tree a, - tree b) -{ - /* Determines whether (A == gcd (A, B)). */ - return tree_int_cst_equal (a, tree_fold_gcd (a, b)); -} - -/* Returns true iff A divides B. */ - -static inline bool -int_divides_p (int a, int b) -{ - return ((b % a) == 0); -} - - - -/* Dump into FILE all the data references from DATAREFS. */ - -void -dump_data_references (FILE *file, VEC (data_reference_p, heap) *datarefs) -{ - unsigned int i; - struct data_reference *dr; - - for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++) - dump_data_reference (file, dr); -} - -/* Dump into FILE all the dependence relations from DDRS. */ - -void -dump_data_dependence_relations (FILE *file, - VEC (ddr_p, heap) *ddrs) -{ - unsigned int i; - struct data_dependence_relation *ddr; - - for (i = 0; VEC_iterate (ddr_p, ddrs, i, ddr); i++) - dump_data_dependence_relation (file, ddr); -} - -/* Dump function for a DATA_REFERENCE structure. */ - -void -dump_data_reference (FILE *outf, - struct data_reference *dr) -{ - unsigned int i; - - fprintf (outf, "(Data Ref: \n stmt: "); - print_generic_stmt (outf, DR_STMT (dr), 0); - fprintf (outf, " ref: "); - print_generic_stmt (outf, DR_REF (dr), 0); - fprintf (outf, " base_object: "); - print_generic_stmt (outf, DR_BASE_OBJECT (dr), 0); - - for (i = 0; i < DR_NUM_DIMENSIONS (dr); i++) - { - fprintf (outf, " Access function %d: ", i); - print_generic_stmt (outf, DR_ACCESS_FN (dr, i), 0); - } - fprintf (outf, ")\n"); -} - -/* Dump function for a SUBSCRIPT structure. */ - -void -dump_subscript (FILE *outf, struct subscript *subscript) -{ - tree chrec = SUB_CONFLICTS_IN_A (subscript); - - fprintf (outf, "\n (subscript \n"); - fprintf (outf, " iterations_that_access_an_element_twice_in_A: "); - print_generic_stmt (outf, chrec, 0); - if (chrec == chrec_known) - fprintf (outf, " (no dependence)\n"); - else if (chrec_contains_undetermined (chrec)) - fprintf (outf, " (don't know)\n"); - else - { - tree last_iteration = SUB_LAST_CONFLICT (subscript); - fprintf (outf, " last_conflict: "); - print_generic_stmt (outf, last_iteration, 0); - } - - chrec = SUB_CONFLICTS_IN_B (subscript); - fprintf (outf, " iterations_that_access_an_element_twice_in_B: "); - print_generic_stmt (outf, chrec, 0); - if (chrec == chrec_known) - fprintf (outf, " (no dependence)\n"); - else if (chrec_contains_undetermined (chrec)) - fprintf (outf, " (don't know)\n"); - else - { - tree last_iteration = SUB_LAST_CONFLICT (subscript); - fprintf (outf, " last_conflict: "); - print_generic_stmt (outf, last_iteration, 0); - } - - fprintf (outf, " (Subscript distance: "); - print_generic_stmt (outf, SUB_DISTANCE (subscript), 0); - fprintf (outf, " )\n"); - fprintf (outf, " )\n"); -} - -/* Print the classic direction vector DIRV to OUTF. */ - -void -print_direction_vector (FILE *outf, - lambda_vector dirv, - int length) -{ - int eq; - - for (eq = 0; eq < length; eq++) - { - enum data_dependence_direction dir = dirv[eq]; - - switch (dir) - { - case dir_positive: - fprintf (outf, " +"); - break; - case dir_negative: - fprintf (outf, " -"); - break; - case dir_equal: - fprintf (outf, " ="); - break; - case dir_positive_or_equal: - fprintf (outf, " +="); - break; - case dir_positive_or_negative: - fprintf (outf, " +-"); - break; - case dir_negative_or_equal: - fprintf (outf, " -="); - break; - case dir_star: - fprintf (outf, " *"); - break; - default: - fprintf (outf, "indep"); - break; - } - } - fprintf (outf, "\n"); -} - -/* Print a vector of direction vectors. */ - -void -print_dir_vectors (FILE *outf, VEC (lambda_vector, heap) *dir_vects, - int length) -{ - unsigned j; - lambda_vector v; - - for (j = 0; VEC_iterate (lambda_vector, dir_vects, j, v); j++) - print_direction_vector (outf, v, length); -} - -/* Print a vector of distance vectors. */ - -void -print_dist_vectors (FILE *outf, VEC (lambda_vector, heap) *dist_vects, - int length) -{ - unsigned j; - lambda_vector v; - - for (j = 0; VEC_iterate (lambda_vector, dist_vects, j, v); j++) - print_lambda_vector (outf, v, length); -} - -/* Debug version. */ - -void -debug_data_dependence_relation (struct data_dependence_relation *ddr) -{ - dump_data_dependence_relation (stderr, ddr); -} - -/* Dump function for a DATA_DEPENDENCE_RELATION structure. */ - -void -dump_data_dependence_relation (FILE *outf, - struct data_dependence_relation *ddr) -{ - struct data_reference *dra, *drb; - - dra = DDR_A (ddr); - drb = DDR_B (ddr); - fprintf (outf, "(Data Dep: \n"); - if (DDR_ARE_DEPENDENT (ddr) == chrec_dont_know) - fprintf (outf, " (don't know)\n"); - - else if (DDR_ARE_DEPENDENT (ddr) == chrec_known) - fprintf (outf, " (no dependence)\n"); - - else if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) - { - unsigned int i; - struct loop *loopi; - - for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) - { - fprintf (outf, " access_fn_A: "); - print_generic_stmt (outf, DR_ACCESS_FN (dra, i), 0); - fprintf (outf, " access_fn_B: "); - print_generic_stmt (outf, DR_ACCESS_FN (drb, i), 0); - dump_subscript (outf, DDR_SUBSCRIPT (ddr, i)); - } - - fprintf (outf, " loop nest: ("); - for (i = 0; VEC_iterate (loop_p, DDR_LOOP_NEST (ddr), i, loopi); i++) - fprintf (outf, "%d ", loopi->num); - fprintf (outf, ")\n"); - - for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) - { - fprintf (outf, " distance_vector: "); - print_lambda_vector (outf, DDR_DIST_VECT (ddr, i), - DDR_NB_LOOPS (ddr)); - } - - for (i = 0; i < DDR_NUM_DIR_VECTS (ddr); i++) - { - fprintf (outf, " direction_vector: "); - print_direction_vector (outf, DDR_DIR_VECT (ddr, i), - DDR_NB_LOOPS (ddr)); - } - } - - fprintf (outf, ")\n"); -} - -/* Dump function for a DATA_DEPENDENCE_DIRECTION structure. */ - -void -dump_data_dependence_direction (FILE *file, - enum data_dependence_direction dir) -{ - switch (dir) - { - case dir_positive: - fprintf (file, "+"); - break; - - case dir_negative: - fprintf (file, "-"); - break; - - case dir_equal: - fprintf (file, "="); - break; - - case dir_positive_or_negative: - fprintf (file, "+-"); - break; - - case dir_positive_or_equal: - fprintf (file, "+="); - break; - - case dir_negative_or_equal: - fprintf (file, "-="); - break; - - case dir_star: - fprintf (file, "*"); - break; - - default: - break; - } -} - -/* Dumps the distance and direction vectors in FILE. DDRS contains - the dependence relations, and VECT_SIZE is the size of the - dependence vectors, or in other words the number of loops in the - considered nest. */ - -void -dump_dist_dir_vectors (FILE *file, VEC (ddr_p, heap) *ddrs) -{ - unsigned int i, j; - struct data_dependence_relation *ddr; - lambda_vector v; - - for (i = 0; VEC_iterate (ddr_p, ddrs, i, ddr); i++) - if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE && DDR_AFFINE_P (ddr)) - { - for (j = 0; VEC_iterate (lambda_vector, DDR_DIST_VECTS (ddr), j, v); j++) - { - fprintf (file, "DISTANCE_V ("); - print_lambda_vector (file, v, DDR_NB_LOOPS (ddr)); - fprintf (file, ")\n"); - } - - for (j = 0; VEC_iterate (lambda_vector, DDR_DIR_VECTS (ddr), j, v); j++) - { - fprintf (file, "DIRECTION_V ("); - print_direction_vector (file, v, DDR_NB_LOOPS (ddr)); - fprintf (file, ")\n"); - } - } - - fprintf (file, "\n\n"); -} - -/* Dumps the data dependence relations DDRS in FILE. */ - -void -dump_ddrs (FILE *file, VEC (ddr_p, heap) *ddrs) -{ - unsigned int i; - struct data_dependence_relation *ddr; - - for (i = 0; VEC_iterate (ddr_p, ddrs, i, ddr); i++) - dump_data_dependence_relation (file, ddr); - - fprintf (file, "\n\n"); -} - - - -/* Estimate the number of iterations from the size of the data and the - access functions. */ - -static void -estimate_niter_from_size_of_data (struct loop *loop, - tree opnd0, - tree access_fn, - tree stmt) -{ - tree estimation = NULL_TREE; - tree array_size, data_size, element_size; - tree init, step; - - init = initial_condition (access_fn); - step = evolution_part_in_loop_num (access_fn, loop->num); - - array_size = TYPE_SIZE (TREE_TYPE (opnd0)); - element_size = TYPE_SIZE (TREE_TYPE (TREE_TYPE (opnd0))); - if (array_size == NULL_TREE - || TREE_CODE (array_size) != INTEGER_CST - || TREE_CODE (element_size) != INTEGER_CST) - return; - - data_size = fold_build2 (EXACT_DIV_EXPR, integer_type_node, - array_size, element_size); - - if (init != NULL_TREE - && step != NULL_TREE - && TREE_CODE (init) == INTEGER_CST - && TREE_CODE (step) == INTEGER_CST) - { - tree i_plus_s = fold_build2 (PLUS_EXPR, integer_type_node, init, step); - tree sign = fold_binary (GT_EXPR, boolean_type_node, i_plus_s, init); - - if (sign == boolean_true_node) - estimation = fold_build2 (CEIL_DIV_EXPR, integer_type_node, - fold_build2 (MINUS_EXPR, integer_type_node, - data_size, init), step); - - /* When the step is negative, as in PR23386: (init = 3, step = - 0ffffffff, data_size = 100), we have to compute the - estimation as ceil_div (init, 0 - step) + 1. */ - else if (sign == boolean_false_node) - estimation = - fold_build2 (PLUS_EXPR, integer_type_node, - fold_build2 (CEIL_DIV_EXPR, integer_type_node, - init, - fold_build2 (MINUS_EXPR, unsigned_type_node, - integer_zero_node, step)), - integer_one_node); - - if (estimation) - record_estimate (loop, estimation, boolean_true_node, stmt); - } -} - -/* Given an ARRAY_REF node REF, records its access functions. - Example: given A[i][3], record in ACCESS_FNS the opnd1 function, - i.e. the constant "3", then recursively call the function on opnd0, - i.e. the ARRAY_REF "A[i]". - If ESTIMATE_ONLY is true, we just set the estimated number of loop - iterations, we don't store the access function. - The function returns the base name: "A". */ - -static tree -analyze_array_indexes (struct loop *loop, - VEC(tree,heap) **access_fns, - tree ref, tree stmt, - bool estimate_only) -{ - tree opnd0, opnd1; - tree access_fn; - - opnd0 = TREE_OPERAND (ref, 0); - opnd1 = TREE_OPERAND (ref, 1); - - /* The detection of the evolution function for this data access is - postponed until the dependence test. This lazy strategy avoids - the computation of access functions that are of no interest for - the optimizers. */ - access_fn = instantiate_parameters - (loop, analyze_scalar_evolution (loop, opnd1)); - - if (estimate_only - && chrec_contains_undetermined (loop->estimated_nb_iterations)) - estimate_niter_from_size_of_data (loop, opnd0, access_fn, stmt); - - if (!estimate_only) - VEC_safe_push (tree, heap, *access_fns, access_fn); - - /* Recursively record other array access functions. */ - if (TREE_CODE (opnd0) == ARRAY_REF) - return analyze_array_indexes (loop, access_fns, opnd0, stmt, estimate_only); - - /* Return the base name of the data access. */ - else - return opnd0; -} - -/* For an array reference REF contained in STMT, attempt to bound the - number of iterations in the loop containing STMT */ - -void -estimate_iters_using_array (tree stmt, tree ref) -{ - analyze_array_indexes (loop_containing_stmt (stmt), NULL, ref, stmt, - true); -} - -/* For a data reference REF contained in the statement STMT, initialize - a DATA_REFERENCE structure, and return it. IS_READ flag has to be - set to true when REF is in the right hand side of an - assignment. */ - -struct data_reference * -analyze_array (tree stmt, tree ref, bool is_read) -{ - struct data_reference *res; - VEC(tree,heap) *acc_fns; - - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "(analyze_array \n"); - fprintf (dump_file, " (ref = "); - print_generic_stmt (dump_file, ref, 0); - fprintf (dump_file, ")\n"); - } - - res = XNEW (struct data_reference); - - DR_STMT (res) = stmt; - DR_REF (res) = ref; - acc_fns = VEC_alloc (tree, heap, 3); - DR_BASE_OBJECT (res) = analyze_array_indexes - (loop_containing_stmt (stmt), &acc_fns, ref, stmt, false); - DR_TYPE (res) = ARRAY_REF_TYPE; - DR_SET_ACCESS_FNS (res, acc_fns); - DR_IS_READ (res) = is_read; - DR_BASE_ADDRESS (res) = NULL_TREE; - DR_OFFSET (res) = NULL_TREE; - DR_INIT (res) = NULL_TREE; - DR_STEP (res) = NULL_TREE; - DR_OFFSET_MISALIGNMENT (res) = NULL_TREE; - DR_MEMTAG (res) = NULL_TREE; - DR_PTR_INFO (res) = NULL; - - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, ")\n"); - - return res; -} - -/* Analyze an indirect memory reference, REF, that comes from STMT. - IS_READ is true if this is an indirect load, and false if it is - an indirect store. - Return a new data reference structure representing the indirect_ref, or - NULL if we cannot describe the access function. */ - -static struct data_reference * -analyze_indirect_ref (tree stmt, tree ref, bool is_read) -{ - struct loop *loop = loop_containing_stmt (stmt); - tree ptr_ref = TREE_OPERAND (ref, 0); - tree access_fn = analyze_scalar_evolution (loop, ptr_ref); - tree init = initial_condition_in_loop_num (access_fn, loop->num); - tree base_address = NULL_TREE, evolution, step = NULL_TREE; - struct ptr_info_def *ptr_info = NULL; - - if (TREE_CODE (ptr_ref) == SSA_NAME) - ptr_info = SSA_NAME_PTR_INFO (ptr_ref); - - STRIP_NOPS (init); - if (access_fn == chrec_dont_know || !init || init == chrec_dont_know) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\nBad access function of ptr: "); - print_generic_expr (dump_file, ref, TDF_SLIM); - fprintf (dump_file, "\n"); - } - return NULL; - } - - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\nAccess function of ptr: "); - print_generic_expr (dump_file, access_fn, TDF_SLIM); - fprintf (dump_file, "\n"); - } - - if (!expr_invariant_in_loop_p (loop, init)) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "\ninitial condition is not loop invariant.\n"); - } - else - { - base_address = init; - evolution = evolution_part_in_loop_num (access_fn, loop->num); - if (evolution != chrec_dont_know) - { - if (!evolution) - step = ssize_int (0); - else - { - if (TREE_CODE (evolution) == INTEGER_CST) - step = fold_convert (ssizetype, evolution); - else - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "\nnon constant step for ptr access.\n"); - } - } - else - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "\nunknown evolution of ptr.\n"); - } - return init_data_ref (stmt, ref, NULL_TREE, access_fn, is_read, base_address, - NULL_TREE, step, NULL_TREE, NULL_TREE, - ptr_info, POINTER_REF_TYPE); -} - -/* For a data reference REF contained in the statement STMT, initialize - a DATA_REFERENCE structure, and return it. */ - -struct data_reference * -init_data_ref (tree stmt, - tree ref, - tree base, - tree access_fn, - bool is_read, - tree base_address, - tree init_offset, - tree step, - tree misalign, - tree memtag, - struct ptr_info_def *ptr_info, - enum data_ref_type type) -{ - struct data_reference *res; - VEC(tree,heap) *acc_fns; - - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "(init_data_ref \n"); - fprintf (dump_file, " (ref = "); - print_generic_stmt (dump_file, ref, 0); - fprintf (dump_file, ")\n"); - } - - res = XNEW (struct data_reference); - - DR_STMT (res) = stmt; - DR_REF (res) = ref; - DR_BASE_OBJECT (res) = base; - DR_TYPE (res) = type; - acc_fns = VEC_alloc (tree, heap, 3); - DR_SET_ACCESS_FNS (res, acc_fns); - VEC_quick_push (tree, DR_ACCESS_FNS (res), access_fn); - DR_IS_READ (res) = is_read; - DR_BASE_ADDRESS (res) = base_address; - DR_OFFSET (res) = init_offset; - DR_INIT (res) = NULL_TREE; - DR_STEP (res) = step; - DR_OFFSET_MISALIGNMENT (res) = misalign; - DR_MEMTAG (res) = memtag; - DR_PTR_INFO (res) = ptr_info; - - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, ")\n"); - - return res; -} - -/* Function strip_conversions - - Strip conversions that don't narrow the mode. */ - -static tree -strip_conversion (tree expr) -{ - tree to, ti, oprnd0; - - while (TREE_CODE (expr) == NOP_EXPR || TREE_CODE (expr) == CONVERT_EXPR) - { - to = TREE_TYPE (expr); - oprnd0 = TREE_OPERAND (expr, 0); - ti = TREE_TYPE (oprnd0); - - if (!INTEGRAL_TYPE_P (to) || !INTEGRAL_TYPE_P (ti)) - return NULL_TREE; - if (GET_MODE_SIZE (TYPE_MODE (to)) < GET_MODE_SIZE (TYPE_MODE (ti))) - return NULL_TREE; - - expr = oprnd0; - } - return expr; -} - - -/* Function analyze_offset_expr - - Given an offset expression EXPR received from get_inner_reference, analyze - it and create an expression for INITIAL_OFFSET by substituting the variables - of EXPR with initial_condition of the corresponding access_fn in the loop. - E.g., - for i - for (j = 3; j < N; j++) - a[j].b[i][j] = 0; - - For a[j].b[i][j], EXPR will be 'i * C_i + j * C_j + C'. 'i' cannot be - substituted, since its access_fn in the inner loop is i. 'j' will be - substituted with 3. An INITIAL_OFFSET will be 'i * C_i + C`', where - C` = 3 * C_j + C. - - Compute MISALIGN (the misalignment of the data reference initial access from - its base). Misalignment can be calculated only if all the variables can be - substituted with constants, otherwise, we record maximum possible alignment - in ALIGNED_TO. In the above example, since 'i' cannot be substituted, MISALIGN - will be NULL_TREE, and the biggest divider of C_i (a power of 2) will be - recorded in ALIGNED_TO. - - STEP is an evolution of the data reference in this loop in bytes. - In the above example, STEP is C_j. - - Return FALSE, if the analysis fails, e.g., there is no access_fn for a - variable. In this case, all the outputs (INITIAL_OFFSET, MISALIGN, ALIGNED_TO - and STEP) are NULL_TREEs. Otherwise, return TRUE. - -*/ - -static bool -analyze_offset_expr (tree expr, - struct loop *loop, - tree *initial_offset, - tree *misalign, - tree *aligned_to, - tree *step) -{ - tree oprnd0; - tree oprnd1; - tree left_offset = ssize_int (0); - tree right_offset = ssize_int (0); - tree left_misalign = ssize_int (0); - tree right_misalign = ssize_int (0); - tree left_step = ssize_int (0); - tree right_step = ssize_int (0); - enum tree_code code; - tree init, evolution; - tree left_aligned_to = NULL_TREE, right_aligned_to = NULL_TREE; - - *step = NULL_TREE; - *misalign = NULL_TREE; - *aligned_to = NULL_TREE; - *initial_offset = NULL_TREE; - - /* Strip conversions that don't narrow the mode. */ - expr = strip_conversion (expr); - if (!expr) - return false; - - /* Stop conditions: - 1. Constant. */ - if (TREE_CODE (expr) == INTEGER_CST) - { - *initial_offset = fold_convert (ssizetype, expr); - *misalign = fold_convert (ssizetype, expr); - *step = ssize_int (0); - return true; - } - - /* 2. Variable. Try to substitute with initial_condition of the corresponding - access_fn in the current loop. */ - if (SSA_VAR_P (expr)) - { - tree access_fn = analyze_scalar_evolution (loop, expr); - - if (access_fn == chrec_dont_know) - /* No access_fn. */ - return false; - - init = initial_condition_in_loop_num (access_fn, loop->num); - if (!expr_invariant_in_loop_p (loop, init)) - /* Not enough information: may be not loop invariant. - E.g., for a[b[i]], we get a[D], where D=b[i]. EXPR is D, its - initial_condition is D, but it depends on i - loop's induction - variable. */ - return false; - - evolution = evolution_part_in_loop_num (access_fn, loop->num); - if (evolution && TREE_CODE (evolution) != INTEGER_CST) - /* Evolution is not constant. */ - return false; - - if (TREE_CODE (init) == INTEGER_CST) - *misalign = fold_convert (ssizetype, init); - else - /* Not constant, misalignment cannot be calculated. */ - *misalign = NULL_TREE; - - *initial_offset = fold_convert (ssizetype, init); - - *step = evolution ? fold_convert (ssizetype, evolution) : ssize_int (0); - return true; - } - - /* Recursive computation. */ - if (!BINARY_CLASS_P (expr)) - { - /* We expect to get binary expressions (PLUS/MINUS and MULT). */ - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\nNot binary expression "); - print_generic_expr (dump_file, expr, TDF_SLIM); - fprintf (dump_file, "\n"); - } - return false; - } - oprnd0 = TREE_OPERAND (expr, 0); - oprnd1 = TREE_OPERAND (expr, 1); - - if (!analyze_offset_expr (oprnd0, loop, &left_offset, &left_misalign, - &left_aligned_to, &left_step) - || !analyze_offset_expr (oprnd1, loop, &right_offset, &right_misalign, - &right_aligned_to, &right_step)) - return false; - - /* The type of the operation: plus, minus or mult. */ - code = TREE_CODE (expr); - switch (code) - { - case MULT_EXPR: - if (TREE_CODE (right_offset) != INTEGER_CST) - /* RIGHT_OFFSET can be not constant. For example, for arrays of variable - sized types. - FORNOW: We don't support such cases. */ - return false; - - /* Strip conversions that don't narrow the mode. */ - left_offset = strip_conversion (left_offset); - if (!left_offset) - return false; - /* Misalignment computation. */ - if (SSA_VAR_P (left_offset)) - { - /* If the left side contains variables that can't be substituted with - constants, the misalignment is unknown. However, if the right side - is a multiple of some alignment, we know that the expression is - aligned to it. Therefore, we record such maximum possible value. - */ - *misalign = NULL_TREE; - *aligned_to = ssize_int (highest_pow2_factor (right_offset)); - } - else - { - /* The left operand was successfully substituted with constant. */ - if (left_misalign) - { - /* In case of EXPR '(i * C1 + j) * C2', LEFT_MISALIGN is - NULL_TREE. */ - *misalign = size_binop (code, left_misalign, right_misalign); - if (left_aligned_to && right_aligned_to) - *aligned_to = size_binop (MIN_EXPR, left_aligned_to, - right_aligned_to); - else - *aligned_to = left_aligned_to ? - left_aligned_to : right_aligned_to; - } - else - *misalign = NULL_TREE; - } - - /* Step calculation. */ - /* Multiply the step by the right operand. */ - *step = size_binop (MULT_EXPR, left_step, right_offset); - break; - - case PLUS_EXPR: - case MINUS_EXPR: - /* Combine the recursive calculations for step and misalignment. */ - *step = size_binop (code, left_step, right_step); - - /* Unknown alignment. */ - if ((!left_misalign && !left_aligned_to) - || (!right_misalign && !right_aligned_to)) - { - *misalign = NULL_TREE; - *aligned_to = NULL_TREE; - break; - } - - if (left_misalign && right_misalign) - *misalign = size_binop (code, left_misalign, right_misalign); - else - *misalign = left_misalign ? left_misalign : right_misalign; - - if (left_aligned_to && right_aligned_to) - *aligned_to = size_binop (MIN_EXPR, left_aligned_to, right_aligned_to); - else - *aligned_to = left_aligned_to ? left_aligned_to : right_aligned_to; - - break; - - default: - gcc_unreachable (); - } - - /* Compute offset. */ - *initial_offset = fold_convert (ssizetype, - fold_build2 (code, TREE_TYPE (left_offset), - left_offset, - right_offset)); - return true; -} - -/* Function address_analysis - - Return the BASE of the address expression EXPR. - Also compute the OFFSET from BASE, MISALIGN and STEP. - - Input: - EXPR - the address expression that is being analyzed - STMT - the statement that contains EXPR or its original memory reference - IS_READ - TRUE if STMT reads from EXPR, FALSE if writes to EXPR - DR - data_reference struct for the original memory reference - - Output: - BASE (returned value) - the base of the data reference EXPR. - INITIAL_OFFSET - initial offset of EXPR from BASE (an expression) - MISALIGN - offset of EXPR from BASE in bytes (a constant) or NULL_TREE if the - computation is impossible - ALIGNED_TO - maximum alignment of EXPR or NULL_TREE if MISALIGN can be - calculated (doesn't depend on variables) - STEP - evolution of EXPR in the loop - - If something unexpected is encountered (an unsupported form of data-ref), - then NULL_TREE is returned. - */ - -static tree -address_analysis (tree expr, tree stmt, bool is_read, struct data_reference *dr, - tree *offset, tree *misalign, tree *aligned_to, tree *step) -{ - tree oprnd0, oprnd1, base_address, offset_expr, base_addr0, base_addr1; - tree address_offset = ssize_int (0), address_misalign = ssize_int (0); - tree dummy, address_aligned_to = NULL_TREE; - struct ptr_info_def *dummy1; - subvar_t dummy2; - - switch (TREE_CODE (expr)) - { - case PLUS_EXPR: - case MINUS_EXPR: - /* EXPR is of form {base +/- offset} (or {offset +/- base}). */ - oprnd0 = TREE_OPERAND (expr, 0); - oprnd1 = TREE_OPERAND (expr, 1); - - STRIP_NOPS (oprnd0); - STRIP_NOPS (oprnd1); - - /* Recursively try to find the base of the address contained in EXPR. - For offset, the returned base will be NULL. */ - base_addr0 = address_analysis (oprnd0, stmt, is_read, dr, &address_offset, - &address_misalign, &address_aligned_to, - step); - - base_addr1 = address_analysis (oprnd1, stmt, is_read, dr, &address_offset, - &address_misalign, &address_aligned_to, - step); - - /* We support cases where only one of the operands contains an - address. */ - if ((base_addr0 && base_addr1) || (!base_addr0 && !base_addr1)) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, - "\neither more than one address or no addresses in expr "); - print_generic_expr (dump_file, expr, TDF_SLIM); - fprintf (dump_file, "\n"); - } - return NULL_TREE; - } - - /* To revert STRIP_NOPS. */ - oprnd0 = TREE_OPERAND (expr, 0); - oprnd1 = TREE_OPERAND (expr, 1); - - offset_expr = base_addr0 ? - fold_convert (ssizetype, oprnd1) : fold_convert (ssizetype, oprnd0); - - /* EXPR is of form {base +/- offset} (or {offset +/- base}). If offset is - a number, we can add it to the misalignment value calculated for base, - otherwise, misalignment is NULL. */ - if (TREE_CODE (offset_expr) == INTEGER_CST && address_misalign) - { - *misalign = size_binop (TREE_CODE (expr), address_misalign, - offset_expr); - *aligned_to = address_aligned_to; - } - else - { - *misalign = NULL_TREE; - *aligned_to = NULL_TREE; - } - - /* Combine offset (from EXPR {base + offset}) with the offset calculated - for base. */ - *offset = size_binop (TREE_CODE (expr), address_offset, offset_expr); - return base_addr0 ? base_addr0 : base_addr1; - - case ADDR_EXPR: - base_address = object_analysis (TREE_OPERAND (expr, 0), stmt, is_read, - &dr, offset, misalign, aligned_to, step, - &dummy, &dummy1, &dummy2); - return base_address; - - case SSA_NAME: - if (!POINTER_TYPE_P (TREE_TYPE (expr))) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\nnot pointer SSA_NAME "); - print_generic_expr (dump_file, expr, TDF_SLIM); - fprintf (dump_file, "\n"); - } - return NULL_TREE; - } - *aligned_to = ssize_int (TYPE_ALIGN_UNIT (TREE_TYPE (TREE_TYPE (expr)))); - *misalign = ssize_int (0); - *offset = ssize_int (0); - *step = ssize_int (0); - return expr; - - default: - return NULL_TREE; - } -} - - -/* Function object_analysis - - Create a data-reference structure DR for MEMREF. - Return the BASE of the data reference MEMREF if the analysis is possible. - Also compute the INITIAL_OFFSET from BASE, MISALIGN and STEP. - E.g., for EXPR a.b[i] + 4B, BASE is a, and OFFSET is the overall offset - 'a.b[i] + 4B' from a (can be an expression), MISALIGN is an OFFSET - instantiated with initial_conditions of access_functions of variables, - and STEP is the evolution of the DR_REF in this loop. - - Function get_inner_reference is used for the above in case of ARRAY_REF and - COMPONENT_REF. - - The structure of the function is as follows: - Part 1: - Case 1. For handled_component_p refs - 1.1 build data-reference structure for MEMREF - 1.2 call get_inner_reference - 1.2.1 analyze offset expr received from get_inner_reference - (fall through with BASE) - Case 2. For declarations - 2.1 set MEMTAG - Case 3. For INDIRECT_REFs - 3.1 build data-reference structure for MEMREF - 3.2 analyze evolution and initial condition of MEMREF - 3.3 set data-reference structure for MEMREF - 3.4 call address_analysis to analyze INIT of the access function - 3.5 extract memory tag - - Part 2: - Combine the results of object and address analysis to calculate - INITIAL_OFFSET, STEP and misalignment info. - - Input: - MEMREF - the memory reference that is being analyzed - STMT - the statement that contains MEMREF - IS_READ - TRUE if STMT reads from MEMREF, FALSE if writes to MEMREF - - Output: - BASE_ADDRESS (returned value) - the base address of the data reference MEMREF - E.g, if MEMREF is a.b[k].c[i][j] the returned - base is &a. - DR - data_reference struct for MEMREF - INITIAL_OFFSET - initial offset of MEMREF from BASE (an expression) - MISALIGN - offset of MEMREF from BASE in bytes (a constant) modulo alignment of - ALIGNMENT or NULL_TREE if the computation is impossible - ALIGNED_TO - maximum alignment of EXPR or NULL_TREE if MISALIGN can be - calculated (doesn't depend on variables) - STEP - evolution of the DR_REF in the loop - MEMTAG - memory tag for aliasing purposes - PTR_INFO - NULL or points-to aliasing info from a pointer SSA_NAME - SUBVARS - Sub-variables of the variable - - If the analysis of MEMREF evolution in the loop fails, NULL_TREE is returned, - but DR can be created anyway. - -*/ - -static tree -object_analysis (tree memref, tree stmt, bool is_read, - struct data_reference **dr, tree *offset, tree *misalign, - tree *aligned_to, tree *step, tree *memtag, - struct ptr_info_def **ptr_info, subvar_t *subvars) -{ - tree base = NULL_TREE, base_address = NULL_TREE; - tree object_offset = ssize_int (0), object_misalign = ssize_int (0); - tree object_step = ssize_int (0), address_step = ssize_int (0); - tree address_offset = ssize_int (0), address_misalign = ssize_int (0); - HOST_WIDE_INT pbitsize, pbitpos; - tree poffset, bit_pos_in_bytes; - enum machine_mode pmode; - int punsignedp, pvolatilep; - tree ptr_step = ssize_int (0), ptr_init = NULL_TREE; - struct loop *loop = loop_containing_stmt (stmt); - struct data_reference *ptr_dr = NULL; - tree object_aligned_to = NULL_TREE, address_aligned_to = NULL_TREE; - tree comp_ref = NULL_TREE; - - *ptr_info = NULL; - - /* Part 1: */ - /* Case 1. handled_component_p refs. */ - if (handled_component_p (memref)) - { - /* 1.1 build data-reference structure for MEMREF. */ - if (!(*dr)) - { - if (TREE_CODE (memref) == ARRAY_REF) - *dr = analyze_array (stmt, memref, is_read); - else if (TREE_CODE (memref) == COMPONENT_REF) - comp_ref = memref; - else - { - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\ndata-ref of unsupported type "); - print_generic_expr (dump_file, memref, TDF_SLIM); - fprintf (dump_file, "\n"); - } - return NULL_TREE; - } - } - - /* 1.2 call get_inner_reference. */ - /* Find the base and the offset from it. */ - base = get_inner_reference (memref, &pbitsize, &pbitpos, &poffset, - &pmode, &punsignedp, &pvolatilep, false); - if (!base) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\nfailed to get inner ref for "); - print_generic_expr (dump_file, memref, TDF_SLIM); - fprintf (dump_file, "\n"); - } - return NULL_TREE; - } - - /* 1.2.1 analyze offset expr received from get_inner_reference. */ - if (poffset - && !analyze_offset_expr (poffset, loop, &object_offset, - &object_misalign, &object_aligned_to, - &object_step)) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\nfailed to compute offset or step for "); - print_generic_expr (dump_file, memref, TDF_SLIM); - fprintf (dump_file, "\n"); - } - return NULL_TREE; - } - - /* Add bit position to OFFSET and MISALIGN. */ - - bit_pos_in_bytes = ssize_int (pbitpos/BITS_PER_UNIT); - /* Check that there is no remainder in bits. */ - if (pbitpos%BITS_PER_UNIT) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "\nbit offset alignment.\n"); - return NULL_TREE; - } - object_offset = size_binop (PLUS_EXPR, bit_pos_in_bytes, object_offset); - if (object_misalign) - object_misalign = size_binop (PLUS_EXPR, object_misalign, - bit_pos_in_bytes); - - memref = base; /* To continue analysis of BASE. */ - /* fall through */ - } - - /* Part 1: Case 2. Declarations. */ - if (DECL_P (memref)) - { - /* We expect to get a decl only if we already have a DR, or with - COMPONENT_REFs of type 'a[i].b'. */ - if (!(*dr)) - { - if (comp_ref && TREE_CODE (TREE_OPERAND (comp_ref, 0)) == ARRAY_REF) - { - *dr = analyze_array (stmt, TREE_OPERAND (comp_ref, 0), is_read); - if (DR_NUM_DIMENSIONS (*dr) != 1) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\n multidimensional component ref "); - print_generic_expr (dump_file, comp_ref, TDF_SLIM); - fprintf (dump_file, "\n"); - } - return NULL_TREE; - } - } - else - { - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\nunhandled decl "); - print_generic_expr (dump_file, memref, TDF_SLIM); - fprintf (dump_file, "\n"); - } - return NULL_TREE; - } - } - - /* TODO: if during the analysis of INDIRECT_REF we get to an object, put - the object in BASE_OBJECT field if we can prove that this is O.K., - i.e., the data-ref access is bounded by the bounds of the BASE_OBJECT. - (e.g., if the object is an array base 'a', where 'a[N]', we must prove - that every access with 'p' (the original INDIRECT_REF based on '&a') - in the loop is within the array boundaries - from a[0] to a[N-1]). - Otherwise, our alias analysis can be incorrect. - Even if an access function based on BASE_OBJECT can't be build, update - BASE_OBJECT field to enable us to prove that two data-refs are - different (without access function, distance analysis is impossible). - */ - if (SSA_VAR_P (memref) && var_can_have_subvars (memref)) - *subvars = get_subvars_for_var (memref); - base_address = build_fold_addr_expr (memref); - /* 2.1 set MEMTAG. */ - *memtag = memref; - } - - /* Part 1: Case 3. INDIRECT_REFs. */ - else if (TREE_CODE (memref) == INDIRECT_REF) - { - tree ptr_ref = TREE_OPERAND (memref, 0); - if (TREE_CODE (ptr_ref) == SSA_NAME) - *ptr_info = SSA_NAME_PTR_INFO (ptr_ref); - - /* 3.1 build data-reference structure for MEMREF. */ - ptr_dr = analyze_indirect_ref (stmt, memref, is_read); - if (!ptr_dr) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\nfailed to create dr for "); - print_generic_expr (dump_file, memref, TDF_SLIM); - fprintf (dump_file, "\n"); - } - return NULL_TREE; - } - - /* 3.2 analyze evolution and initial condition of MEMREF. */ - ptr_step = DR_STEP (ptr_dr); - ptr_init = DR_BASE_ADDRESS (ptr_dr); - if (!ptr_init || !ptr_step || !POINTER_TYPE_P (TREE_TYPE (ptr_init))) - { - *dr = (*dr) ? *dr : ptr_dr; - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\nbad pointer access "); - print_generic_expr (dump_file, memref, TDF_SLIM); - fprintf (dump_file, "\n"); - } - return NULL_TREE; - } - - if (integer_zerop (ptr_step) && !(*dr)) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "\nptr is loop invariant.\n"); - *dr = ptr_dr; - return NULL_TREE; - - /* If there exists DR for MEMREF, we are analyzing the base of - handled component (PTR_INIT), which not necessary has evolution in - the loop. */ - } - object_step = size_binop (PLUS_EXPR, object_step, ptr_step); - - /* 3.3 set data-reference structure for MEMREF. */ - if (!*dr) - *dr = ptr_dr; - - /* 3.4 call address_analysis to analyze INIT of the access - function. */ - base_address = address_analysis (ptr_init, stmt, is_read, *dr, - &address_offset, &address_misalign, - &address_aligned_to, &address_step); - if (!base_address) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\nfailed to analyze address "); - print_generic_expr (dump_file, ptr_init, TDF_SLIM); - fprintf (dump_file, "\n"); - } - return NULL_TREE; - } - - /* 3.5 extract memory tag. */ - switch (TREE_CODE (base_address)) - { - case SSA_NAME: - *memtag = get_var_ann (SSA_NAME_VAR (base_address))->symbol_mem_tag; - if (!(*memtag) && TREE_CODE (TREE_OPERAND (memref, 0)) == SSA_NAME) - *memtag = get_var_ann ( - SSA_NAME_VAR (TREE_OPERAND (memref, 0)))->symbol_mem_tag; - break; - case ADDR_EXPR: - *memtag = TREE_OPERAND (base_address, 0); - break; - default: - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\nno memtag for "); - print_generic_expr (dump_file, memref, TDF_SLIM); - fprintf (dump_file, "\n"); - } - *memtag = NULL_TREE; - break; - } - } - - if (!base_address) - { - /* MEMREF cannot be analyzed. */ - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\ndata-ref of unsupported type "); - print_generic_expr (dump_file, memref, TDF_SLIM); - fprintf (dump_file, "\n"); - } - return NULL_TREE; - } - - if (comp_ref) - DR_REF (*dr) = comp_ref; - - if (SSA_VAR_P (*memtag) && var_can_have_subvars (*memtag)) - *subvars = get_subvars_for_var (*memtag); - - /* Part 2: Combine the results of object and address analysis to calculate - INITIAL_OFFSET, STEP and misalignment info. */ - *offset = size_binop (PLUS_EXPR, object_offset, address_offset); - - if ((!object_misalign && !object_aligned_to) - || (!address_misalign && !address_aligned_to)) - { - *misalign = NULL_TREE; - *aligned_to = NULL_TREE; - } - else - { - if (object_misalign && address_misalign) - *misalign = size_binop (PLUS_EXPR, object_misalign, address_misalign); - else - *misalign = object_misalign ? object_misalign : address_misalign; - if (object_aligned_to && address_aligned_to) - *aligned_to = size_binop (MIN_EXPR, object_aligned_to, - address_aligned_to); - else - *aligned_to = object_aligned_to ? - object_aligned_to : address_aligned_to; - } - *step = size_binop (PLUS_EXPR, object_step, address_step); - - return base_address; -} - -/* Function analyze_offset. - - Extract INVARIANT and CONSTANT parts from OFFSET. - -*/ -static bool -analyze_offset (tree offset, tree *invariant, tree *constant) -{ - tree op0, op1, constant_0, constant_1, invariant_0, invariant_1; - enum tree_code code = TREE_CODE (offset); - - *invariant = NULL_TREE; - *constant = NULL_TREE; - - /* Not PLUS/MINUS expression - recursion stop condition. */ - if (code != PLUS_EXPR && code != MINUS_EXPR) - { - if (TREE_CODE (offset) == INTEGER_CST) - *constant = offset; - else - *invariant = offset; - return true; - } - - op0 = TREE_OPERAND (offset, 0); - op1 = TREE_OPERAND (offset, 1); - - /* Recursive call with the operands. */ - if (!analyze_offset (op0, &invariant_0, &constant_0) - || !analyze_offset (op1, &invariant_1, &constant_1)) - return false; - - /* Combine the results. Add negation to the subtrahend in case of - subtraction. */ - if (constant_0 && constant_1) - return false; - *constant = constant_0 ? constant_0 : constant_1; - if (code == MINUS_EXPR && constant_1) - *constant = fold_build1 (NEGATE_EXPR, TREE_TYPE (*constant), *constant); - - if (invariant_0 && invariant_1) - *invariant = - fold_build2 (code, TREE_TYPE (invariant_0), invariant_0, invariant_1); - else - { - *invariant = invariant_0 ? invariant_0 : invariant_1; - if (code == MINUS_EXPR && invariant_1) - *invariant = - fold_build1 (NEGATE_EXPR, TREE_TYPE (*invariant), *invariant); - } - return true; -} - -/* Free the memory used by the data reference DR. */ - -static void -free_data_ref (data_reference_p dr) -{ - DR_FREE_ACCESS_FNS (dr); - free (dr); -} - -/* Function create_data_ref. - - Create a data-reference structure for MEMREF. Set its DR_BASE_ADDRESS, - DR_OFFSET, DR_INIT, DR_STEP, DR_OFFSET_MISALIGNMENT, DR_ALIGNED_TO, - DR_MEMTAG, and DR_POINTSTO_INFO fields. - - Input: - MEMREF - the memory reference that is being analyzed - STMT - the statement that contains MEMREF - IS_READ - TRUE if STMT reads from MEMREF, FALSE if writes to MEMREF - - Output: - DR (returned value) - data_reference struct for MEMREF -*/ - -static struct data_reference * -create_data_ref (tree memref, tree stmt, bool is_read) -{ - struct data_reference *dr = NULL; - tree base_address, offset, step, misalign, memtag; - struct loop *loop = loop_containing_stmt (stmt); - tree invariant = NULL_TREE, constant = NULL_TREE; - tree type_size, init_cond; - struct ptr_info_def *ptr_info; - subvar_t subvars = NULL; - tree aligned_to, type = NULL_TREE, orig_offset; - - if (!memref) - return NULL; - - base_address = object_analysis (memref, stmt, is_read, &dr, &offset, - &misalign, &aligned_to, &step, &memtag, - &ptr_info, &subvars); - if (!dr || !base_address) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\ncreate_data_ref: failed to create a dr for "); - print_generic_expr (dump_file, memref, TDF_SLIM); - fprintf (dump_file, "\n"); - } - return NULL; - } - - DR_BASE_ADDRESS (dr) = base_address; - DR_OFFSET (dr) = offset; - DR_INIT (dr) = ssize_int (0); - DR_STEP (dr) = step; - DR_OFFSET_MISALIGNMENT (dr) = misalign; - DR_ALIGNED_TO (dr) = aligned_to; - DR_MEMTAG (dr) = memtag; - DR_PTR_INFO (dr) = ptr_info; - DR_SUBVARS (dr) = subvars; - - type_size = fold_convert (ssizetype, TYPE_SIZE_UNIT (TREE_TYPE (DR_REF (dr)))); - - /* Extract CONSTANT and INVARIANT from OFFSET. */ - /* Remove cast from OFFSET and restore it for INVARIANT part. */ - orig_offset = offset; - STRIP_NOPS (offset); - if (offset != orig_offset) - type = TREE_TYPE (orig_offset); - if (!analyze_offset (offset, &invariant, &constant)) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\ncreate_data_ref: failed to analyze dr's"); - fprintf (dump_file, " offset for "); - print_generic_expr (dump_file, memref, TDF_SLIM); - fprintf (dump_file, "\n"); - } - return NULL; - } - if (type && invariant) - invariant = fold_convert (type, invariant); - - /* Put CONSTANT part of OFFSET in DR_INIT and INVARIANT in DR_OFFSET field - of DR. */ - if (constant) - { - DR_INIT (dr) = fold_convert (ssizetype, constant); - init_cond = fold_build2 (TRUNC_DIV_EXPR, TREE_TYPE (constant), - constant, type_size); - } - else - DR_INIT (dr) = init_cond = ssize_int (0); - - if (invariant) - DR_OFFSET (dr) = invariant; - else - DR_OFFSET (dr) = ssize_int (0); - - /* Change the access function for INIDIRECT_REFs, according to - DR_BASE_ADDRESS. Analyze OFFSET calculated in object_analysis. OFFSET is - an expression that can contain loop invariant expressions and constants. - We put the constant part in the initial condition of the access function - (for data dependence tests), and in DR_INIT of the data-ref. The loop - invariant part is put in DR_OFFSET. - The evolution part of the access function is STEP calculated in - object_analysis divided by the size of data type. - */ - if (!DR_BASE_OBJECT (dr) - || (TREE_CODE (memref) == COMPONENT_REF && DR_NUM_DIMENSIONS (dr) == 1)) - { - tree access_fn; - tree new_step; - - /* Update access function. */ - access_fn = DR_ACCESS_FN (dr, 0); - if (automatically_generated_chrec_p (access_fn)) - { - free_data_ref (dr); - return NULL; - } - - new_step = size_binop (TRUNC_DIV_EXPR, - fold_convert (ssizetype, step), type_size); - - init_cond = chrec_convert (chrec_type (access_fn), init_cond, stmt); - new_step = chrec_convert (chrec_type (access_fn), new_step, stmt); - if (automatically_generated_chrec_p (init_cond) - || automatically_generated_chrec_p (new_step)) - { - free_data_ref (dr); - return NULL; - } - access_fn = chrec_replace_initial_condition (access_fn, init_cond); - access_fn = reset_evolution_in_loop (loop->num, access_fn, new_step); - - VEC_replace (tree, DR_ACCESS_FNS (dr), 0, access_fn); - } - - if (dump_file && (dump_flags & TDF_DETAILS)) - { - struct ptr_info_def *pi = DR_PTR_INFO (dr); - - fprintf (dump_file, "\nCreated dr for "); - print_generic_expr (dump_file, memref, TDF_SLIM); - fprintf (dump_file, "\n\tbase_address: "); - print_generic_expr (dump_file, DR_BASE_ADDRESS (dr), TDF_SLIM); - fprintf (dump_file, "\n\toffset from base address: "); - print_generic_expr (dump_file, DR_OFFSET (dr), TDF_SLIM); - fprintf (dump_file, "\n\tconstant offset from base address: "); - print_generic_expr (dump_file, DR_INIT (dr), TDF_SLIM); - fprintf (dump_file, "\n\tbase_object: "); - print_generic_expr (dump_file, DR_BASE_OBJECT (dr), TDF_SLIM); - fprintf (dump_file, "\n\tstep: "); - print_generic_expr (dump_file, DR_STEP (dr), TDF_SLIM); - fprintf (dump_file, "B\n\tmisalignment from base: "); - print_generic_expr (dump_file, DR_OFFSET_MISALIGNMENT (dr), TDF_SLIM); - if (DR_OFFSET_MISALIGNMENT (dr)) - fprintf (dump_file, "B"); - if (DR_ALIGNED_TO (dr)) - { - fprintf (dump_file, "\n\taligned to: "); - print_generic_expr (dump_file, DR_ALIGNED_TO (dr), TDF_SLIM); - } - fprintf (dump_file, "\n\tmemtag: "); - print_generic_expr (dump_file, DR_MEMTAG (dr), TDF_SLIM); - fprintf (dump_file, "\n"); - if (pi && pi->name_mem_tag) - { - fprintf (dump_file, "\n\tnametag: "); - print_generic_expr (dump_file, pi->name_mem_tag, TDF_SLIM); - fprintf (dump_file, "\n"); - } - } - return dr; -} - - -/* Returns true when all the functions of a tree_vec CHREC are the - same. */ - -static bool -all_chrecs_equal_p (tree chrec) -{ - int j; - - for (j = 0; j < TREE_VEC_LENGTH (chrec) - 1; j++) - if (!eq_evolutions_p (TREE_VEC_ELT (chrec, j), - TREE_VEC_ELT (chrec, j + 1))) - return false; - - return true; -} - -/* Determine for each subscript in the data dependence relation DDR - the distance. */ - -static void -compute_subscript_distance (struct data_dependence_relation *ddr) -{ - if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) - { - unsigned int i; - - for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) - { - tree conflicts_a, conflicts_b, difference; - struct subscript *subscript; - - subscript = DDR_SUBSCRIPT (ddr, i); - conflicts_a = SUB_CONFLICTS_IN_A (subscript); - conflicts_b = SUB_CONFLICTS_IN_B (subscript); - - if (TREE_CODE (conflicts_a) == TREE_VEC) - { - if (!all_chrecs_equal_p (conflicts_a)) - { - SUB_DISTANCE (subscript) = chrec_dont_know; - return; - } - else - conflicts_a = TREE_VEC_ELT (conflicts_a, 0); - } - - if (TREE_CODE (conflicts_b) == TREE_VEC) - { - if (!all_chrecs_equal_p (conflicts_b)) - { - SUB_DISTANCE (subscript) = chrec_dont_know; - return; - } - else - conflicts_b = TREE_VEC_ELT (conflicts_b, 0); - } - - conflicts_b = chrec_convert (integer_type_node, conflicts_b, - NULL_TREE); - conflicts_a = chrec_convert (integer_type_node, conflicts_a, - NULL_TREE); - difference = chrec_fold_minus - (integer_type_node, conflicts_b, conflicts_a); - - if (evolution_function_is_constant_p (difference)) - SUB_DISTANCE (subscript) = difference; - - else - SUB_DISTANCE (subscript) = chrec_dont_know; - } - } -} - -/* Initialize a data dependence relation between data accesses A and - B. NB_LOOPS is the number of loops surrounding the references: the - size of the classic distance/direction vectors. */ - -static struct data_dependence_relation * -initialize_data_dependence_relation (struct data_reference *a, - struct data_reference *b, - VEC (loop_p, heap) *loop_nest) -{ - struct data_dependence_relation *res; - bool differ_p, known_dependence; - unsigned int i; - - res = XNEW (struct data_dependence_relation); - DDR_A (res) = a; - DDR_B (res) = b; - DDR_LOOP_NEST (res) = NULL; - - if (a == NULL || b == NULL) - { - DDR_ARE_DEPENDENT (res) = chrec_dont_know; - return res; - } - - /* When A and B are arrays and their dimensions differ, we directly - initialize the relation to "there is no dependence": chrec_known. */ - if (DR_BASE_OBJECT (a) && DR_BASE_OBJECT (b) - && DR_NUM_DIMENSIONS (a) != DR_NUM_DIMENSIONS (b)) - { - DDR_ARE_DEPENDENT (res) = chrec_known; - return res; - } - - if (DR_BASE_ADDRESS (a) && DR_BASE_ADDRESS (b)) - known_dependence = base_addr_differ_p (a, b, &differ_p); - else - known_dependence = base_object_differ_p (a, b, &differ_p); - - if (!known_dependence) - { - /* Can't determine whether the data-refs access the same memory - region. */ - DDR_ARE_DEPENDENT (res) = chrec_dont_know; - return res; - } - - if (differ_p) - { - DDR_ARE_DEPENDENT (res) = chrec_known; - return res; - } - - DDR_AFFINE_P (res) = true; - DDR_ARE_DEPENDENT (res) = NULL_TREE; - DDR_SUBSCRIPTS (res) = VEC_alloc (subscript_p, heap, DR_NUM_DIMENSIONS (a)); - DDR_LOOP_NEST (res) = loop_nest; - DDR_DIR_VECTS (res) = NULL; - DDR_DIST_VECTS (res) = NULL; - - for (i = 0; i < DR_NUM_DIMENSIONS (a); i++) - { - struct subscript *subscript; - - subscript = XNEW (struct subscript); - SUB_CONFLICTS_IN_A (subscript) = chrec_dont_know; - SUB_CONFLICTS_IN_B (subscript) = chrec_dont_know; - SUB_LAST_CONFLICT (subscript) = chrec_dont_know; - SUB_DISTANCE (subscript) = chrec_dont_know; - VEC_safe_push (subscript_p, heap, DDR_SUBSCRIPTS (res), subscript); - } - - return res; -} - -/* Set DDR_ARE_DEPENDENT to CHREC and finalize the subscript overlap - description. */ - -static inline void -finalize_ddr_dependent (struct data_dependence_relation *ddr, - tree chrec) -{ - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "(dependence classified: "); - print_generic_expr (dump_file, chrec, 0); - fprintf (dump_file, ")\n"); - } - - DDR_ARE_DEPENDENT (ddr) = chrec; - VEC_free (subscript_p, heap, DDR_SUBSCRIPTS (ddr)); -} - -/* The dependence relation DDR cannot be represented by a distance - vector. */ - -static inline void -non_affine_dependence_relation (struct data_dependence_relation *ddr) -{ - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "(Dependence relation cannot be represented by distance vector.) \n"); - - DDR_AFFINE_P (ddr) = false; -} - - - -/* This section contains the classic Banerjee tests. */ - -/* Returns true iff CHREC_A and CHREC_B are not dependent on any index - variables, i.e., if the ZIV (Zero Index Variable) test is true. */ - -static inline bool -ziv_subscript_p (tree chrec_a, - tree chrec_b) -{ - return (evolution_function_is_constant_p (chrec_a) - && evolution_function_is_constant_p (chrec_b)); -} - -/* Returns true iff CHREC_A and CHREC_B are dependent on an index - variable, i.e., if the SIV (Single Index Variable) test is true. */ - -static bool -siv_subscript_p (tree chrec_a, - tree chrec_b) -{ - if ((evolution_function_is_constant_p (chrec_a) - && evolution_function_is_univariate_p (chrec_b)) - || (evolution_function_is_constant_p (chrec_b) - && evolution_function_is_univariate_p (chrec_a))) - return true; - - if (evolution_function_is_univariate_p (chrec_a) - && evolution_function_is_univariate_p (chrec_b)) - { - switch (TREE_CODE (chrec_a)) - { - case POLYNOMIAL_CHREC: - switch (TREE_CODE (chrec_b)) - { - case POLYNOMIAL_CHREC: - if (CHREC_VARIABLE (chrec_a) != CHREC_VARIABLE (chrec_b)) - return false; - - default: - return true; - } - - default: - return true; - } - } - - return false; -} - -/* Analyze a ZIV (Zero Index Variable) subscript. *OVERLAPS_A and - *OVERLAPS_B are initialized to the functions that describe the - relation between the elements accessed twice by CHREC_A and - CHREC_B. For k >= 0, the following property is verified: - - CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ - -static void -analyze_ziv_subscript (tree chrec_a, - tree chrec_b, - tree *overlaps_a, - tree *overlaps_b, - tree *last_conflicts) -{ - tree difference; - dependence_stats.num_ziv++; - - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "(analyze_ziv_subscript \n"); - - chrec_a = chrec_convert (integer_type_node, chrec_a, NULL_TREE); - chrec_b = chrec_convert (integer_type_node, chrec_b, NULL_TREE); - difference = chrec_fold_minus (integer_type_node, chrec_a, chrec_b); - - switch (TREE_CODE (difference)) - { - case INTEGER_CST: - if (integer_zerop (difference)) - { - /* The difference is equal to zero: the accessed index - overlaps for each iteration in the loop. */ - *overlaps_a = integer_zero_node; - *overlaps_b = integer_zero_node; - *last_conflicts = chrec_dont_know; - dependence_stats.num_ziv_dependent++; - } - else - { - /* The accesses do not overlap. */ - *overlaps_a = chrec_known; - *overlaps_b = chrec_known; - *last_conflicts = integer_zero_node; - dependence_stats.num_ziv_independent++; - } - break; - - default: - /* We're not sure whether the indexes overlap. For the moment, - conservatively answer "don't know". */ - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "ziv test failed: difference is non-integer.\n"); - - *overlaps_a = chrec_dont_know; - *overlaps_b = chrec_dont_know; - *last_conflicts = chrec_dont_know; - dependence_stats.num_ziv_unimplemented++; - break; - } - - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, ")\n"); -} - -/* Get the real or estimated number of iterations for LOOPNUM, whichever is - available. Return the number of iterations as a tree, or NULL_TREE if - we don't know. */ - -static tree -get_number_of_iters_for_loop (int loopnum) -{ - tree numiter = number_of_iterations_in_loop (current_loops->parray[loopnum]); - - if (TREE_CODE (numiter) != INTEGER_CST) - numiter = current_loops->parray[loopnum]->estimated_nb_iterations; - if (chrec_contains_undetermined (numiter)) - return NULL_TREE; - return numiter; -} - -/* Analyze a SIV (Single Index Variable) subscript where CHREC_A is a - constant, and CHREC_B is an affine function. *OVERLAPS_A and - *OVERLAPS_B are initialized to the functions that describe the - relation between the elements accessed twice by CHREC_A and - CHREC_B. For k >= 0, the following property is verified: - - CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ - -static void -analyze_siv_subscript_cst_affine (tree chrec_a, - tree chrec_b, - tree *overlaps_a, - tree *overlaps_b, - tree *last_conflicts) -{ - bool value0, value1, value2; - tree difference; - - chrec_a = chrec_convert (integer_type_node, chrec_a, NULL_TREE); - chrec_b = chrec_convert (integer_type_node, chrec_b, NULL_TREE); - difference = chrec_fold_minus - (integer_type_node, initial_condition (chrec_b), chrec_a); - - if (!chrec_is_positive (initial_condition (difference), &value0)) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "siv test failed: chrec is not positive.\n"); - - dependence_stats.num_siv_unimplemented++; - *overlaps_a = chrec_dont_know; - *overlaps_b = chrec_dont_know; - *last_conflicts = chrec_dont_know; - return; - } - else - { - if (value0 == false) - { - if (!chrec_is_positive (CHREC_RIGHT (chrec_b), &value1)) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "siv test failed: chrec not positive.\n"); - - *overlaps_a = chrec_dont_know; - *overlaps_b = chrec_dont_know; - *last_conflicts = chrec_dont_know; - dependence_stats.num_siv_unimplemented++; - return; - } - else - { - if (value1 == true) - { - /* Example: - chrec_a = 12 - chrec_b = {10, +, 1} - */ - - if (tree_fold_divides_p (CHREC_RIGHT (chrec_b), difference)) - { - tree numiter; - int loopnum = CHREC_VARIABLE (chrec_b); - - *overlaps_a = integer_zero_node; - *overlaps_b = fold_build2 (EXACT_DIV_EXPR, integer_type_node, - fold_build1 (ABS_EXPR, - integer_type_node, - difference), - CHREC_RIGHT (chrec_b)); - *last_conflicts = integer_one_node; - - - /* Perform weak-zero siv test to see if overlap is - outside the loop bounds. */ - numiter = get_number_of_iters_for_loop (loopnum); - - if (numiter != NULL_TREE - && TREE_CODE (*overlaps_b) == INTEGER_CST - && tree_int_cst_lt (numiter, *overlaps_b)) - { - *overlaps_a = chrec_known; - *overlaps_b = chrec_known; - *last_conflicts = integer_zero_node; - dependence_stats.num_siv_independent++; - return; - } - dependence_stats.num_siv_dependent++; - return; - } - - /* When the step does not divide the difference, there are - no overlaps. */ - else - { - *overlaps_a = chrec_known; - *overlaps_b = chrec_known; - *last_conflicts = integer_zero_node; - dependence_stats.num_siv_independent++; - return; - } - } - - else - { - /* Example: - chrec_a = 12 - chrec_b = {10, +, -1} - - In this case, chrec_a will not overlap with chrec_b. */ - *overlaps_a = chrec_known; - *overlaps_b = chrec_known; - *last_conflicts = integer_zero_node; - dependence_stats.num_siv_independent++; - return; - } - } - } - else - { - if (!chrec_is_positive (CHREC_RIGHT (chrec_b), &value2)) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "siv test failed: chrec not positive.\n"); - - *overlaps_a = chrec_dont_know; - *overlaps_b = chrec_dont_know; - *last_conflicts = chrec_dont_know; - dependence_stats.num_siv_unimplemented++; - return; - } - else - { - if (value2 == false) - { - /* Example: - chrec_a = 3 - chrec_b = {10, +, -1} - */ - if (tree_fold_divides_p (CHREC_RIGHT (chrec_b), difference)) - { - tree numiter; - int loopnum = CHREC_VARIABLE (chrec_b); - - *overlaps_a = integer_zero_node; - *overlaps_b = fold_build2 (EXACT_DIV_EXPR, - integer_type_node, difference, - CHREC_RIGHT (chrec_b)); - *last_conflicts = integer_one_node; - - /* Perform weak-zero siv test to see if overlap is - outside the loop bounds. */ - numiter = get_number_of_iters_for_loop (loopnum); - - if (numiter != NULL_TREE - && TREE_CODE (*overlaps_b) == INTEGER_CST - && tree_int_cst_lt (numiter, *overlaps_b)) - { - *overlaps_a = chrec_known; - *overlaps_b = chrec_known; - *last_conflicts = integer_zero_node; - dependence_stats.num_siv_independent++; - return; - } - dependence_stats.num_siv_dependent++; - return; - } - - /* When the step does not divide the difference, there - are no overlaps. */ - else - { - *overlaps_a = chrec_known; - *overlaps_b = chrec_known; - *last_conflicts = integer_zero_node; - dependence_stats.num_siv_independent++; - return; - } - } - else - { - /* Example: - chrec_a = 3 - chrec_b = {4, +, 1} - - In this case, chrec_a will not overlap with chrec_b. */ - *overlaps_a = chrec_known; - *overlaps_b = chrec_known; - *last_conflicts = integer_zero_node; - dependence_stats.num_siv_independent++; - return; - } - } - } - } -} - -/* Helper recursive function for initializing the matrix A. Returns - the initial value of CHREC. */ - -static int -initialize_matrix_A (lambda_matrix A, tree chrec, unsigned index, int mult) -{ - gcc_assert (chrec); - - if (TREE_CODE (chrec) != POLYNOMIAL_CHREC) - return int_cst_value (chrec); - - A[index][0] = mult * int_cst_value (CHREC_RIGHT (chrec)); - return initialize_matrix_A (A, CHREC_LEFT (chrec), index + 1, mult); -} - -#define FLOOR_DIV(x,y) ((x) / (y)) - -/* Solves the special case of the Diophantine equation: - | {0, +, STEP_A}_x (OVERLAPS_A) = {0, +, STEP_B}_y (OVERLAPS_B) - - Computes the descriptions OVERLAPS_A and OVERLAPS_B. NITER is the - number of iterations that loops X and Y run. The overlaps will be - constructed as evolutions in dimension DIM. */ - -static void -compute_overlap_steps_for_affine_univar (int niter, int step_a, int step_b, - tree *overlaps_a, tree *overlaps_b, - tree *last_conflicts, int dim) -{ - if (((step_a > 0 && step_b > 0) - || (step_a < 0 && step_b < 0))) - { - int step_overlaps_a, step_overlaps_b; - int gcd_steps_a_b, last_conflict, tau2; - - gcd_steps_a_b = gcd (step_a, step_b); - step_overlaps_a = step_b / gcd_steps_a_b; - step_overlaps_b = step_a / gcd_steps_a_b; - - tau2 = FLOOR_DIV (niter, step_overlaps_a); - tau2 = MIN (tau2, FLOOR_DIV (niter, step_overlaps_b)); - last_conflict = tau2; - - *overlaps_a = build_polynomial_chrec - (dim, integer_zero_node, - build_int_cst (NULL_TREE, step_overlaps_a)); - *overlaps_b = build_polynomial_chrec - (dim, integer_zero_node, - build_int_cst (NULL_TREE, step_overlaps_b)); - *last_conflicts = build_int_cst (NULL_TREE, last_conflict); - } - - else - { - *overlaps_a = integer_zero_node; - *overlaps_b = integer_zero_node; - *last_conflicts = integer_zero_node; - } -} - - -/* Solves the special case of a Diophantine equation where CHREC_A is - an affine bivariate function, and CHREC_B is an affine univariate - function. For example, - - | {{0, +, 1}_x, +, 1335}_y = {0, +, 1336}_z - - has the following overlapping functions: - - | x (t, u, v) = {{0, +, 1336}_t, +, 1}_v - | y (t, u, v) = {{0, +, 1336}_u, +, 1}_v - | z (t, u, v) = {{{0, +, 1}_t, +, 1335}_u, +, 1}_v - - FORNOW: This is a specialized implementation for a case occurring in - a common benchmark. Implement the general algorithm. */ - -static void -compute_overlap_steps_for_affine_1_2 (tree chrec_a, tree chrec_b, - tree *overlaps_a, tree *overlaps_b, - tree *last_conflicts) -{ - bool xz_p, yz_p, xyz_p; - int step_x, step_y, step_z; - int niter_x, niter_y, niter_z, niter; - tree numiter_x, numiter_y, numiter_z; - tree overlaps_a_xz, overlaps_b_xz, last_conflicts_xz; - tree overlaps_a_yz, overlaps_b_yz, last_conflicts_yz; - tree overlaps_a_xyz, overlaps_b_xyz, last_conflicts_xyz; - - step_x = int_cst_value (CHREC_RIGHT (CHREC_LEFT (chrec_a))); - step_y = int_cst_value (CHREC_RIGHT (chrec_a)); - step_z = int_cst_value (CHREC_RIGHT (chrec_b)); - - numiter_x = get_number_of_iters_for_loop (CHREC_VARIABLE (CHREC_LEFT (chrec_a))); - numiter_y = get_number_of_iters_for_loop (CHREC_VARIABLE (chrec_a)); - numiter_z = get_number_of_iters_for_loop (CHREC_VARIABLE (chrec_b)); - - if (numiter_x == NULL_TREE || numiter_y == NULL_TREE - || numiter_z == NULL_TREE) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "overlap steps test failed: no iteration counts.\n"); - - *overlaps_a = chrec_dont_know; - *overlaps_b = chrec_dont_know; - *last_conflicts = chrec_dont_know; - return; - } - - niter_x = int_cst_value (numiter_x); - niter_y = int_cst_value (numiter_y); - niter_z = int_cst_value (numiter_z); - - niter = MIN (niter_x, niter_z); - compute_overlap_steps_for_affine_univar (niter, step_x, step_z, - &overlaps_a_xz, - &overlaps_b_xz, - &last_conflicts_xz, 1); - niter = MIN (niter_y, niter_z); - compute_overlap_steps_for_affine_univar (niter, step_y, step_z, - &overlaps_a_yz, - &overlaps_b_yz, - &last_conflicts_yz, 2); - niter = MIN (niter_x, niter_z); - niter = MIN (niter_y, niter); - compute_overlap_steps_for_affine_univar (niter, step_x + step_y, step_z, - &overlaps_a_xyz, - &overlaps_b_xyz, - &last_conflicts_xyz, 3); - - xz_p = !integer_zerop (last_conflicts_xz); - yz_p = !integer_zerop (last_conflicts_yz); - xyz_p = !integer_zerop (last_conflicts_xyz); - - if (xz_p || yz_p || xyz_p) - { - *overlaps_a = make_tree_vec (2); - TREE_VEC_ELT (*overlaps_a, 0) = integer_zero_node; - TREE_VEC_ELT (*overlaps_a, 1) = integer_zero_node; - *overlaps_b = integer_zero_node; - if (xz_p) - { - tree t0 = chrec_convert (integer_type_node, - TREE_VEC_ELT (*overlaps_a, 0), NULL_TREE); - tree t1 = chrec_convert (integer_type_node, overlaps_a_xz, - NULL_TREE); - tree t2 = chrec_convert (integer_type_node, *overlaps_b, - NULL_TREE); - tree t3 = chrec_convert (integer_type_node, overlaps_b_xz, - NULL_TREE); - - TREE_VEC_ELT (*overlaps_a, 0) = chrec_fold_plus (integer_type_node, - t0, t1); - *overlaps_b = chrec_fold_plus (integer_type_node, t2, t3); - *last_conflicts = last_conflicts_xz; - } - if (yz_p) - { - tree t0 = chrec_convert (integer_type_node, - TREE_VEC_ELT (*overlaps_a, 1), NULL_TREE); - tree t1 = chrec_convert (integer_type_node, overlaps_a_yz, NULL_TREE); - tree t2 = chrec_convert (integer_type_node, *overlaps_b, NULL_TREE); - tree t3 = chrec_convert (integer_type_node, overlaps_b_yz, NULL_TREE); - - TREE_VEC_ELT (*overlaps_a, 1) = chrec_fold_plus (integer_type_node, - t0, t1); - *overlaps_b = chrec_fold_plus (integer_type_node, t2, t3); - *last_conflicts = last_conflicts_yz; - } - if (xyz_p) - { - tree t0 = chrec_convert (integer_type_node, - TREE_VEC_ELT (*overlaps_a, 0), NULL_TREE); - tree t1 = chrec_convert (integer_type_node, overlaps_a_xyz, - NULL_TREE); - tree t2 = chrec_convert (integer_type_node, - TREE_VEC_ELT (*overlaps_a, 1), NULL_TREE); - tree t3 = chrec_convert (integer_type_node, overlaps_a_xyz, - NULL_TREE); - tree t4 = chrec_convert (integer_type_node, *overlaps_b, NULL_TREE); - tree t5 = chrec_convert (integer_type_node, overlaps_b_xyz, - NULL_TREE); - - TREE_VEC_ELT (*overlaps_a, 0) = chrec_fold_plus (integer_type_node, - t0, t1); - TREE_VEC_ELT (*overlaps_a, 1) = chrec_fold_plus (integer_type_node, - t2, t3); - *overlaps_b = chrec_fold_plus (integer_type_node, t4, t5); - *last_conflicts = last_conflicts_xyz; - } - } - else - { - *overlaps_a = integer_zero_node; - *overlaps_b = integer_zero_node; - *last_conflicts = integer_zero_node; - } -} - -/* Determines the overlapping elements due to accesses CHREC_A and - CHREC_B, that are affine functions. This function cannot handle - symbolic evolution functions, ie. when initial conditions are - parameters, because it uses lambda matrices of integers. */ - -static void -analyze_subscript_affine_affine (tree chrec_a, - tree chrec_b, - tree *overlaps_a, - tree *overlaps_b, - tree *last_conflicts) -{ - unsigned nb_vars_a, nb_vars_b, dim; - int init_a, init_b, gamma, gcd_alpha_beta; - int tau1, tau2; - lambda_matrix A, U, S; - - if (eq_evolutions_p (chrec_a, chrec_b)) - { - /* The accessed index overlaps for each iteration in the - loop. */ - *overlaps_a = integer_zero_node; - *overlaps_b = integer_zero_node; - *last_conflicts = chrec_dont_know; - return; - } - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "(analyze_subscript_affine_affine \n"); - - /* For determining the initial intersection, we have to solve a - Diophantine equation. This is the most time consuming part. - - For answering to the question: "Is there a dependence?" we have - to prove that there exists a solution to the Diophantine - equation, and that the solution is in the iteration domain, - i.e. the solution is positive or zero, and that the solution - happens before the upper bound loop.nb_iterations. Otherwise - there is no dependence. This function outputs a description of - the iterations that hold the intersections. */ - - nb_vars_a = nb_vars_in_chrec (chrec_a); - nb_vars_b = nb_vars_in_chrec (chrec_b); - - dim = nb_vars_a + nb_vars_b; - U = lambda_matrix_new (dim, dim); - A = lambda_matrix_new (dim, 1); - S = lambda_matrix_new (dim, 1); - - init_a = initialize_matrix_A (A, chrec_a, 0, 1); - init_b = initialize_matrix_A (A, chrec_b, nb_vars_a, -1); - gamma = init_b - init_a; - - /* Don't do all the hard work of solving the Diophantine equation - when we already know the solution: for example, - | {3, +, 1}_1 - | {3, +, 4}_2 - | gamma = 3 - 3 = 0. - Then the first overlap occurs during the first iterations: - | {3, +, 1}_1 ({0, +, 4}_x) = {3, +, 4}_2 ({0, +, 1}_x) - */ - if (gamma == 0) - { - if (nb_vars_a == 1 && nb_vars_b == 1) - { - int step_a, step_b; - int niter, niter_a, niter_b; - tree numiter_a, numiter_b; - - numiter_a = get_number_of_iters_for_loop (CHREC_VARIABLE (chrec_a)); - numiter_b = get_number_of_iters_for_loop (CHREC_VARIABLE (chrec_b)); - if (numiter_a == NULL_TREE || numiter_b == NULL_TREE) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "affine-affine test failed: missing iteration counts.\n"); - *overlaps_a = chrec_dont_know; - *overlaps_b = chrec_dont_know; - *last_conflicts = chrec_dont_know; - goto end_analyze_subs_aa; - } - - niter_a = int_cst_value (numiter_a); - niter_b = int_cst_value (numiter_b); - niter = MIN (niter_a, niter_b); - - step_a = int_cst_value (CHREC_RIGHT (chrec_a)); - step_b = int_cst_value (CHREC_RIGHT (chrec_b)); - - compute_overlap_steps_for_affine_univar (niter, step_a, step_b, - overlaps_a, overlaps_b, - last_conflicts, 1); - } - - else if (nb_vars_a == 2 && nb_vars_b == 1) - compute_overlap_steps_for_affine_1_2 - (chrec_a, chrec_b, overlaps_a, overlaps_b, last_conflicts); - - else if (nb_vars_a == 1 && nb_vars_b == 2) - compute_overlap_steps_for_affine_1_2 - (chrec_b, chrec_a, overlaps_b, overlaps_a, last_conflicts); - - else - { - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "affine-affine test failed: too many variables.\n"); - *overlaps_a = chrec_dont_know; - *overlaps_b = chrec_dont_know; - *last_conflicts = chrec_dont_know; - } - goto end_analyze_subs_aa; - } - - /* U.A = S */ - lambda_matrix_right_hermite (A, dim, 1, S, U); - - if (S[0][0] < 0) - { - S[0][0] *= -1; - lambda_matrix_row_negate (U, dim, 0); - } - gcd_alpha_beta = S[0][0]; - - /* Something went wrong: for example in {1, +, 0}_5 vs. {0, +, 0}_5, - but that is a quite strange case. Instead of ICEing, answer - don't know. */ - if (gcd_alpha_beta == 0) - { - *overlaps_a = chrec_dont_know; - *overlaps_b = chrec_dont_know; - *last_conflicts = chrec_dont_know; - goto end_analyze_subs_aa; - } - - /* The classic "gcd-test". */ - if (!int_divides_p (gcd_alpha_beta, gamma)) - { - /* The "gcd-test" has determined that there is no integer - solution, i.e. there is no dependence. */ - *overlaps_a = chrec_known; - *overlaps_b = chrec_known; - *last_conflicts = integer_zero_node; - } - - /* Both access functions are univariate. This includes SIV and MIV cases. */ - else if (nb_vars_a == 1 && nb_vars_b == 1) - { - /* Both functions should have the same evolution sign. */ - if (((A[0][0] > 0 && -A[1][0] > 0) - || (A[0][0] < 0 && -A[1][0] < 0))) - { - /* The solutions are given by: - | - | [GAMMA/GCD_ALPHA_BETA t].[u11 u12] = [x0] - | [u21 u22] [y0] - - For a given integer t. Using the following variables, - - | i0 = u11 * gamma / gcd_alpha_beta - | j0 = u12 * gamma / gcd_alpha_beta - | i1 = u21 - | j1 = u22 - - the solutions are: - - | x0 = i0 + i1 * t, - | y0 = j0 + j1 * t. */ - - int i0, j0, i1, j1; - - /* X0 and Y0 are the first iterations for which there is a - dependence. X0, Y0 are two solutions of the Diophantine - equation: chrec_a (X0) = chrec_b (Y0). */ - int x0, y0; - int niter, niter_a, niter_b; - tree numiter_a, numiter_b; - - numiter_a = get_number_of_iters_for_loop (CHREC_VARIABLE (chrec_a)); - numiter_b = get_number_of_iters_for_loop (CHREC_VARIABLE (chrec_b)); - - if (numiter_a == NULL_TREE || numiter_b == NULL_TREE) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "affine-affine test failed: missing iteration counts.\n"); - *overlaps_a = chrec_dont_know; - *overlaps_b = chrec_dont_know; - *last_conflicts = chrec_dont_know; - goto end_analyze_subs_aa; - } - - niter_a = int_cst_value (numiter_a); - niter_b = int_cst_value (numiter_b); - niter = MIN (niter_a, niter_b); - - i0 = U[0][0] * gamma / gcd_alpha_beta; - j0 = U[0][1] * gamma / gcd_alpha_beta; - i1 = U[1][0]; - j1 = U[1][1]; - - if ((i1 == 0 && i0 < 0) - || (j1 == 0 && j0 < 0)) - { - /* There is no solution. - FIXME: The case "i0 > nb_iterations, j0 > nb_iterations" - falls in here, but for the moment we don't look at the - upper bound of the iteration domain. */ - *overlaps_a = chrec_known; - *overlaps_b = chrec_known; - *last_conflicts = integer_zero_node; - } - - else - { - if (i1 > 0) - { - tau1 = CEIL (-i0, i1); - tau2 = FLOOR_DIV (niter - i0, i1); - - if (j1 > 0) - { - int last_conflict, min_multiple; - tau1 = MAX (tau1, CEIL (-j0, j1)); - tau2 = MIN (tau2, FLOOR_DIV (niter - j0, j1)); - - x0 = i1 * tau1 + i0; - y0 = j1 * tau1 + j0; - - /* At this point (x0, y0) is one of the - solutions to the Diophantine equation. The - next step has to compute the smallest - positive solution: the first conflicts. */ - min_multiple = MIN (x0 / i1, y0 / j1); - x0 -= i1 * min_multiple; - y0 -= j1 * min_multiple; - - tau1 = (x0 - i0)/i1; - last_conflict = tau2 - tau1; - - /* If the overlap occurs outside of the bounds of the - loop, there is no dependence. */ - if (x0 > niter || y0 > niter) - { - *overlaps_a = chrec_known; - *overlaps_b = chrec_known; - *last_conflicts = integer_zero_node; - } - else - { - *overlaps_a = build_polynomial_chrec - (1, - build_int_cst (NULL_TREE, x0), - build_int_cst (NULL_TREE, i1)); - *overlaps_b = build_polynomial_chrec - (1, - build_int_cst (NULL_TREE, y0), - build_int_cst (NULL_TREE, j1)); - *last_conflicts = build_int_cst (NULL_TREE, last_conflict); - } - } - else - { - /* FIXME: For the moment, the upper bound of the - iteration domain for j is not checked. */ - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "affine-affine test failed: unimplemented.\n"); - *overlaps_a = chrec_dont_know; - *overlaps_b = chrec_dont_know; - *last_conflicts = chrec_dont_know; - } - } - - else - { - /* FIXME: For the moment, the upper bound of the - iteration domain for i is not checked. */ - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "affine-affine test failed: unimplemented.\n"); - *overlaps_a = chrec_dont_know; - *overlaps_b = chrec_dont_know; - *last_conflicts = chrec_dont_know; - } - } - } - else - { - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "affine-affine test failed: unimplemented.\n"); - *overlaps_a = chrec_dont_know; - *overlaps_b = chrec_dont_know; - *last_conflicts = chrec_dont_know; - } - } - - else - { - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "affine-affine test failed: unimplemented.\n"); - *overlaps_a = chrec_dont_know; - *overlaps_b = chrec_dont_know; - *last_conflicts = chrec_dont_know; - } - -end_analyze_subs_aa: - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, " (overlaps_a = "); - print_generic_expr (dump_file, *overlaps_a, 0); - fprintf (dump_file, ")\n (overlaps_b = "); - print_generic_expr (dump_file, *overlaps_b, 0); - fprintf (dump_file, ")\n"); - fprintf (dump_file, ")\n"); - } -} - -/* Returns true when analyze_subscript_affine_affine can be used for - determining the dependence relation between chrec_a and chrec_b, - that contain symbols. This function modifies chrec_a and chrec_b - such that the analysis result is the same, and such that they don't - contain symbols, and then can safely be passed to the analyzer. - - Example: The analysis of the following tuples of evolutions produce - the same results: {x+1, +, 1}_1 vs. {x+3, +, 1}_1, and {-2, +, 1}_1 - vs. {0, +, 1}_1 - - {x+1, +, 1}_1 ({2, +, 1}_1) = {x+3, +, 1}_1 ({0, +, 1}_1) - {-2, +, 1}_1 ({2, +, 1}_1) = {0, +, 1}_1 ({0, +, 1}_1) -*/ - -static bool -can_use_analyze_subscript_affine_affine (tree *chrec_a, tree *chrec_b) -{ - tree diff, type, left_a, left_b, right_b; - - if (chrec_contains_symbols (CHREC_RIGHT (*chrec_a)) - || chrec_contains_symbols (CHREC_RIGHT (*chrec_b))) - /* FIXME: For the moment not handled. Might be refined later. */ - return false; - - type = chrec_type (*chrec_a); - left_a = CHREC_LEFT (*chrec_a); - left_b = chrec_convert (type, CHREC_LEFT (*chrec_b), NULL_TREE); - diff = chrec_fold_minus (type, left_a, left_b); - - if (!evolution_function_is_constant_p (diff)) - return false; - - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "can_use_subscript_aff_aff_for_symbolic \n"); - - *chrec_a = build_polynomial_chrec (CHREC_VARIABLE (*chrec_a), - diff, CHREC_RIGHT (*chrec_a)); - right_b = chrec_convert (type, CHREC_RIGHT (*chrec_b), NULL_TREE); - *chrec_b = build_polynomial_chrec (CHREC_VARIABLE (*chrec_b), - build_int_cst (type, 0), - right_b); - return true; -} - -/* Analyze a SIV (Single Index Variable) subscript. *OVERLAPS_A and - *OVERLAPS_B are initialized to the functions that describe the - relation between the elements accessed twice by CHREC_A and - CHREC_B. For k >= 0, the following property is verified: - - CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ - -static void -analyze_siv_subscript (tree chrec_a, - tree chrec_b, - tree *overlaps_a, - tree *overlaps_b, - tree *last_conflicts) -{ - dependence_stats.num_siv++; - - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "(analyze_siv_subscript \n"); - - if (evolution_function_is_constant_p (chrec_a) - && evolution_function_is_affine_p (chrec_b)) - analyze_siv_subscript_cst_affine (chrec_a, chrec_b, - overlaps_a, overlaps_b, last_conflicts); - - else if (evolution_function_is_affine_p (chrec_a) - && evolution_function_is_constant_p (chrec_b)) - analyze_siv_subscript_cst_affine (chrec_b, chrec_a, - overlaps_b, overlaps_a, last_conflicts); - - else if (evolution_function_is_affine_p (chrec_a) - && evolution_function_is_affine_p (chrec_b)) - { - if (!chrec_contains_symbols (chrec_a) - && !chrec_contains_symbols (chrec_b)) - { - analyze_subscript_affine_affine (chrec_a, chrec_b, - overlaps_a, overlaps_b, - last_conflicts); - - if (*overlaps_a == chrec_dont_know - || *overlaps_b == chrec_dont_know) - dependence_stats.num_siv_unimplemented++; - else if (*overlaps_a == chrec_known - || *overlaps_b == chrec_known) - dependence_stats.num_siv_independent++; - else - dependence_stats.num_siv_dependent++; - } - else if (can_use_analyze_subscript_affine_affine (&chrec_a, - &chrec_b)) - { - analyze_subscript_affine_affine (chrec_a, chrec_b, - overlaps_a, overlaps_b, - last_conflicts); - /* FIXME: The number of iterations is a symbolic expression. - Compute it properly. */ - *last_conflicts = chrec_dont_know; - - if (*overlaps_a == chrec_dont_know - || *overlaps_b == chrec_dont_know) - dependence_stats.num_siv_unimplemented++; - else if (*overlaps_a == chrec_known - || *overlaps_b == chrec_known) - dependence_stats.num_siv_independent++; - else - dependence_stats.num_siv_dependent++; - } - else - goto siv_subscript_dontknow; - } - - else - { - siv_subscript_dontknow:; - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "siv test failed: unimplemented.\n"); - *overlaps_a = chrec_dont_know; - *overlaps_b = chrec_dont_know; - *last_conflicts = chrec_dont_know; - dependence_stats.num_siv_unimplemented++; - } - - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, ")\n"); -} - -/* Return true when the property can be computed. RES should contain - true when calling the first time this function, then it is set to - false when one of the evolution steps of an affine CHREC does not - divide the constant CST. */ - -static bool -chrec_steps_divide_constant_p (tree chrec, - tree cst, - bool *res) -{ - switch (TREE_CODE (chrec)) - { - case POLYNOMIAL_CHREC: - if (evolution_function_is_constant_p (CHREC_RIGHT (chrec))) - { - if (tree_fold_divides_p (CHREC_RIGHT (chrec), cst)) - /* Keep RES to true, and iterate on other dimensions. */ - return chrec_steps_divide_constant_p (CHREC_LEFT (chrec), cst, res); - - *res = false; - return true; - } - else - /* When the step is a parameter the result is undetermined. */ - return false; - - default: - /* On the initial condition, return true. */ - return true; - } -} - -/* Analyze a MIV (Multiple Index Variable) subscript. *OVERLAPS_A and - *OVERLAPS_B are initialized to the functions that describe the - relation between the elements accessed twice by CHREC_A and - CHREC_B. For k >= 0, the following property is verified: - - CHREC_A (*OVERLAPS_A (k)) = CHREC_B (*OVERLAPS_B (k)). */ - -static void -analyze_miv_subscript (tree chrec_a, - tree chrec_b, - tree *overlaps_a, - tree *overlaps_b, - tree *last_conflicts) -{ - /* FIXME: This is a MIV subscript, not yet handled. - Example: (A[{1, +, 1}_1] vs. A[{1, +, 1}_2]) that comes from - (A[i] vs. A[j]). - - In the SIV test we had to solve a Diophantine equation with two - variables. In the MIV case we have to solve a Diophantine - equation with 2*n variables (if the subscript uses n IVs). - */ - bool divide_p = true; - tree difference; - dependence_stats.num_miv++; - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "(analyze_miv_subscript \n"); - - chrec_a = chrec_convert (integer_type_node, chrec_a, NULL_TREE); - chrec_b = chrec_convert (integer_type_node, chrec_b, NULL_TREE); - difference = chrec_fold_minus (integer_type_node, chrec_a, chrec_b); - - if (eq_evolutions_p (chrec_a, chrec_b)) - { - /* Access functions are the same: all the elements are accessed - in the same order. */ - *overlaps_a = integer_zero_node; - *overlaps_b = integer_zero_node; - *last_conflicts = get_number_of_iters_for_loop (CHREC_VARIABLE (chrec_a)); - dependence_stats.num_miv_dependent++; - } - - else if (evolution_function_is_constant_p (difference) - /* For the moment, the following is verified: - evolution_function_is_affine_multivariate_p (chrec_a) */ - && chrec_steps_divide_constant_p (chrec_a, difference, ÷_p) - && !divide_p) - { - /* testsuite/.../ssa-chrec-33.c - {{21, +, 2}_1, +, -2}_2 vs. {{20, +, 2}_1, +, -2}_2 - - The difference is 1, and the evolution steps are equal to 2, - consequently there are no overlapping elements. */ - *overlaps_a = chrec_known; - *overlaps_b = chrec_known; - *last_conflicts = integer_zero_node; - dependence_stats.num_miv_independent++; - } - - else if (evolution_function_is_affine_multivariate_p (chrec_a) - && !chrec_contains_symbols (chrec_a) - && evolution_function_is_affine_multivariate_p (chrec_b) - && !chrec_contains_symbols (chrec_b)) - { - /* testsuite/.../ssa-chrec-35.c - {0, +, 1}_2 vs. {0, +, 1}_3 - the overlapping elements are respectively located at iterations: - {0, +, 1}_x and {0, +, 1}_x, - in other words, we have the equality: - {0, +, 1}_2 ({0, +, 1}_x) = {0, +, 1}_3 ({0, +, 1}_x) - - Other examples: - {{0, +, 1}_1, +, 2}_2 ({0, +, 1}_x, {0, +, 1}_y) = - {0, +, 1}_1 ({{0, +, 1}_x, +, 2}_y) - - {{0, +, 2}_1, +, 3}_2 ({0, +, 1}_y, {0, +, 1}_x) = - {{0, +, 3}_1, +, 2}_2 ({0, +, 1}_x, {0, +, 1}_y) - */ - analyze_subscript_affine_affine (chrec_a, chrec_b, - overlaps_a, overlaps_b, last_conflicts); - - if (*overlaps_a == chrec_dont_know - || *overlaps_b == chrec_dont_know) - dependence_stats.num_miv_unimplemented++; - else if (*overlaps_a == chrec_known - || *overlaps_b == chrec_known) - dependence_stats.num_miv_independent++; - else - dependence_stats.num_miv_dependent++; - } - - else - { - /* When the analysis is too difficult, answer "don't know". */ - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "analyze_miv_subscript test failed: unimplemented.\n"); - - *overlaps_a = chrec_dont_know; - *overlaps_b = chrec_dont_know; - *last_conflicts = chrec_dont_know; - dependence_stats.num_miv_unimplemented++; - } - - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, ")\n"); -} - -/* Determines the iterations for which CHREC_A is equal to CHREC_B. - OVERLAP_ITERATIONS_A and OVERLAP_ITERATIONS_B are initialized with - two functions that describe the iterations that contain conflicting - elements. - - Remark: For an integer k >= 0, the following equality is true: - - CHREC_A (OVERLAP_ITERATIONS_A (k)) == CHREC_B (OVERLAP_ITERATIONS_B (k)). -*/ - -static void -analyze_overlapping_iterations (tree chrec_a, - tree chrec_b, - tree *overlap_iterations_a, - tree *overlap_iterations_b, - tree *last_conflicts) -{ - dependence_stats.num_subscript_tests++; - - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "(analyze_overlapping_iterations \n"); - fprintf (dump_file, " (chrec_a = "); - print_generic_expr (dump_file, chrec_a, 0); - fprintf (dump_file, ")\n (chrec_b = "); - print_generic_expr (dump_file, chrec_b, 0); - fprintf (dump_file, ")\n"); - } - - if (chrec_a == NULL_TREE - || chrec_b == NULL_TREE - || chrec_contains_undetermined (chrec_a) - || chrec_contains_undetermined (chrec_b)) - { - dependence_stats.num_subscript_undetermined++; - - *overlap_iterations_a = chrec_dont_know; - *overlap_iterations_b = chrec_dont_know; - } - - /* If they are the same chrec, and are affine, they overlap - on every iteration. */ - else if (eq_evolutions_p (chrec_a, chrec_b) - && evolution_function_is_affine_multivariate_p (chrec_a)) - { - dependence_stats.num_same_subscript_function++; - *overlap_iterations_a = integer_zero_node; - *overlap_iterations_b = integer_zero_node; - *last_conflicts = chrec_dont_know; - } - - /* If they aren't the same, and aren't affine, we can't do anything - yet. */ - else if ((chrec_contains_symbols (chrec_a) - || chrec_contains_symbols (chrec_b)) - && (!evolution_function_is_affine_multivariate_p (chrec_a) - || !evolution_function_is_affine_multivariate_p (chrec_b))) - { - dependence_stats.num_subscript_undetermined++; - *overlap_iterations_a = chrec_dont_know; - *overlap_iterations_b = chrec_dont_know; - } - - else if (ziv_subscript_p (chrec_a, chrec_b)) - analyze_ziv_subscript (chrec_a, chrec_b, - overlap_iterations_a, overlap_iterations_b, - last_conflicts); - - else if (siv_subscript_p (chrec_a, chrec_b)) - analyze_siv_subscript (chrec_a, chrec_b, - overlap_iterations_a, overlap_iterations_b, - last_conflicts); - - else - analyze_miv_subscript (chrec_a, chrec_b, - overlap_iterations_a, overlap_iterations_b, - last_conflicts); - - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, " (overlap_iterations_a = "); - print_generic_expr (dump_file, *overlap_iterations_a, 0); - fprintf (dump_file, ")\n (overlap_iterations_b = "); - print_generic_expr (dump_file, *overlap_iterations_b, 0); - fprintf (dump_file, ")\n"); - fprintf (dump_file, ")\n"); - } -} - -/* Helper function for uniquely inserting distance vectors. */ - -static void -save_dist_v (struct data_dependence_relation *ddr, lambda_vector dist_v) -{ - unsigned i; - lambda_vector v; - - for (i = 0; VEC_iterate (lambda_vector, DDR_DIST_VECTS (ddr), i, v); i++) - if (lambda_vector_equal (v, dist_v, DDR_NB_LOOPS (ddr))) - return; - - VEC_safe_push (lambda_vector, heap, DDR_DIST_VECTS (ddr), dist_v); -} - -/* Helper function for uniquely inserting direction vectors. */ - -static void -save_dir_v (struct data_dependence_relation *ddr, lambda_vector dir_v) -{ - unsigned i; - lambda_vector v; - - for (i = 0; VEC_iterate (lambda_vector, DDR_DIR_VECTS (ddr), i, v); i++) - if (lambda_vector_equal (v, dir_v, DDR_NB_LOOPS (ddr))) - return; - - VEC_safe_push (lambda_vector, heap, DDR_DIR_VECTS (ddr), dir_v); -} - -/* Add a distance of 1 on all the loops outer than INDEX. If we - haven't yet determined a distance for this outer loop, push a new - distance vector composed of the previous distance, and a distance - of 1 for this outer loop. Example: - - | loop_1 - | loop_2 - | A[10] - | endloop_2 - | endloop_1 - - Saved vectors are of the form (dist_in_1, dist_in_2). First, we - save (0, 1), then we have to save (1, 0). */ - -static void -add_outer_distances (struct data_dependence_relation *ddr, - lambda_vector dist_v, int index) -{ - /* For each outer loop where init_v is not set, the accesses are - in dependence of distance 1 in the loop. */ - while (--index >= 0) - { - lambda_vector save_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); - lambda_vector_copy (dist_v, save_v, DDR_NB_LOOPS (ddr)); - save_v[index] = 1; - save_dist_v (ddr, save_v); - } -} - -/* Return false when fail to represent the data dependence as a - distance vector. INIT_B is set to true when a component has been - added to the distance vector DIST_V. INDEX_CARRY is then set to - the index in DIST_V that carries the dependence. */ - -static bool -build_classic_dist_vector_1 (struct data_dependence_relation *ddr, - struct data_reference *ddr_a, - struct data_reference *ddr_b, - lambda_vector dist_v, bool *init_b, - int *index_carry) -{ - unsigned i; - lambda_vector init_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); - - for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) - { - tree access_fn_a, access_fn_b; - struct subscript *subscript = DDR_SUBSCRIPT (ddr, i); - - if (chrec_contains_undetermined (SUB_DISTANCE (subscript))) - { - non_affine_dependence_relation (ddr); - return false; - } - - access_fn_a = DR_ACCESS_FN (ddr_a, i); - access_fn_b = DR_ACCESS_FN (ddr_b, i); - - if (TREE_CODE (access_fn_a) == POLYNOMIAL_CHREC - && TREE_CODE (access_fn_b) == POLYNOMIAL_CHREC) - { - int dist, index; - int index_a = index_in_loop_nest (CHREC_VARIABLE (access_fn_a), - DDR_LOOP_NEST (ddr)); - int index_b = index_in_loop_nest (CHREC_VARIABLE (access_fn_b), - DDR_LOOP_NEST (ddr)); - - /* The dependence is carried by the outermost loop. Example: - | loop_1 - | A[{4, +, 1}_1] - | loop_2 - | A[{5, +, 1}_2] - | endloop_2 - | endloop_1 - In this case, the dependence is carried by loop_1. */ - index = index_a < index_b ? index_a : index_b; - *index_carry = MIN (index, *index_carry); - - if (chrec_contains_undetermined (SUB_DISTANCE (subscript))) - { - non_affine_dependence_relation (ddr); - return false; - } - - dist = int_cst_value (SUB_DISTANCE (subscript)); - - /* This is the subscript coupling test. If we have already - recorded a distance for this loop (a distance coming from - another subscript), it should be the same. For example, - in the following code, there is no dependence: - - | loop i = 0, N, 1 - | T[i+1][i] = ... - | ... = T[i][i] - | endloop - */ - if (init_v[index] != 0 && dist_v[index] != dist) - { - finalize_ddr_dependent (ddr, chrec_known); - return false; - } - - dist_v[index] = dist; - init_v[index] = 1; - *init_b = true; - } - else - { - /* This can be for example an affine vs. constant dependence - (T[i] vs. T[3]) that is not an affine dependence and is - not representable as a distance vector. */ - non_affine_dependence_relation (ddr); - return false; - } - } - - return true; -} - -/* Return true when the DDR contains two data references that have the - same access functions. */ - -static bool -same_access_functions (struct data_dependence_relation *ddr) -{ - unsigned i; - - for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) - if (!eq_evolutions_p (DR_ACCESS_FN (DDR_A (ddr), i), - DR_ACCESS_FN (DDR_B (ddr), i))) - return false; - - return true; -} - -/* Helper function for the case where DDR_A and DDR_B are the same - multivariate access function. */ - -static void -add_multivariate_self_dist (struct data_dependence_relation *ddr, tree c_2) -{ - int x_1, x_2; - tree c_1 = CHREC_LEFT (c_2); - tree c_0 = CHREC_LEFT (c_1); - lambda_vector dist_v; - - /* Polynomials with more than 2 variables are not handled yet. */ - if (TREE_CODE (c_0) != INTEGER_CST) - { - DDR_ARE_DEPENDENT (ddr) = chrec_dont_know; - return; - } - - x_2 = index_in_loop_nest (CHREC_VARIABLE (c_2), DDR_LOOP_NEST (ddr)); - x_1 = index_in_loop_nest (CHREC_VARIABLE (c_1), DDR_LOOP_NEST (ddr)); - - /* For "{{0, +, 2}_1, +, 3}_2" the distance vector is (3, -2). */ - dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); - dist_v[x_1] = int_cst_value (CHREC_RIGHT (c_2)); - dist_v[x_2] = -int_cst_value (CHREC_RIGHT (c_1)); - save_dist_v (ddr, dist_v); - - add_outer_distances (ddr, dist_v, x_1); -} - -/* Helper function for the case where DDR_A and DDR_B are the same - access functions. */ - -static void -add_other_self_distances (struct data_dependence_relation *ddr) -{ - lambda_vector dist_v; - unsigned i; - int index_carry = DDR_NB_LOOPS (ddr); - - for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++) - { - tree access_fun = DR_ACCESS_FN (DDR_A (ddr), i); - - if (TREE_CODE (access_fun) == POLYNOMIAL_CHREC) - { - if (!evolution_function_is_univariate_p (access_fun)) - { - if (DDR_NUM_SUBSCRIPTS (ddr) != 1) - { - DDR_ARE_DEPENDENT (ddr) = chrec_dont_know; - return; - } - - add_multivariate_self_dist (ddr, DR_ACCESS_FN (DDR_A (ddr), 0)); - return; - } - - index_carry = MIN (index_carry, - index_in_loop_nest (CHREC_VARIABLE (access_fun), - DDR_LOOP_NEST (ddr))); - } - } - - dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); - add_outer_distances (ddr, dist_v, index_carry); -} - -/* Compute the classic per loop distance vector. DDR is the data - dependence relation to build a vector from. Return false when fail - to represent the data dependence as a distance vector. */ - -static bool -build_classic_dist_vector (struct data_dependence_relation *ddr) -{ - bool init_b = false; - int index_carry = DDR_NB_LOOPS (ddr); - lambda_vector dist_v; - - if (DDR_ARE_DEPENDENT (ddr) != NULL_TREE) - return true; - - if (same_access_functions (ddr)) - { - /* Save the 0 vector. */ - dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); - save_dist_v (ddr, dist_v); - - if (DDR_NB_LOOPS (ddr) > 1) - add_other_self_distances (ddr); - - return true; - } - - dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); - if (!build_classic_dist_vector_1 (ddr, DDR_A (ddr), DDR_B (ddr), - dist_v, &init_b, &index_carry)) - return false; - - /* Save the distance vector if we initialized one. */ - if (init_b) - { - /* Verify a basic constraint: classic distance vectors should - always be lexicographically positive. - - Data references are collected in the order of execution of - the program, thus for the following loop - - | for (i = 1; i < 100; i++) - | for (j = 1; j < 100; j++) - | { - | t = T[j+1][i-1]; // A - | T[j][i] = t + 2; // B - | } - - references are collected following the direction of the wind: - A then B. The data dependence tests are performed also - following this order, such that we're looking at the distance - separating the elements accessed by A from the elements later - accessed by B. But in this example, the distance returned by - test_dep (A, B) is lexicographically negative (-1, 1), that - means that the access A occurs later than B with respect to - the outer loop, ie. we're actually looking upwind. In this - case we solve test_dep (B, A) looking downwind to the - lexicographically positive solution, that returns the - distance vector (1, -1). */ - if (!lambda_vector_lexico_pos (dist_v, DDR_NB_LOOPS (ddr))) - { - lambda_vector save_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); - subscript_dependence_tester_1 (ddr, DDR_B (ddr), DDR_A (ddr)); - compute_subscript_distance (ddr); - build_classic_dist_vector_1 (ddr, DDR_B (ddr), DDR_A (ddr), - save_v, &init_b, &index_carry); - save_dist_v (ddr, save_v); - - /* In this case there is a dependence forward for all the - outer loops: - - | for (k = 1; k < 100; k++) - | for (i = 1; i < 100; i++) - | for (j = 1; j < 100; j++) - | { - | t = T[j+1][i-1]; // A - | T[j][i] = t + 2; // B - | } - - the vectors are: - (0, 1, -1) - (1, 1, -1) - (1, -1, 1) - */ - if (DDR_NB_LOOPS (ddr) > 1) - { - add_outer_distances (ddr, save_v, index_carry); - add_outer_distances (ddr, dist_v, index_carry); - } - } - else - { - lambda_vector save_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); - lambda_vector_copy (dist_v, save_v, DDR_NB_LOOPS (ddr)); - save_dist_v (ddr, save_v); - - if (DDR_NB_LOOPS (ddr) > 1) - { - lambda_vector opposite_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); - - subscript_dependence_tester_1 (ddr, DDR_B (ddr), DDR_A (ddr)); - compute_subscript_distance (ddr); - build_classic_dist_vector_1 (ddr, DDR_B (ddr), DDR_A (ddr), - opposite_v, &init_b, &index_carry); - - add_outer_distances (ddr, dist_v, index_carry); - add_outer_distances (ddr, opposite_v, index_carry); - } - } - } - else - { - /* There is a distance of 1 on all the outer loops: Example: - there is a dependence of distance 1 on loop_1 for the array A. - - | loop_1 - | A[5] = ... - | endloop - */ - add_outer_distances (ddr, dist_v, - lambda_vector_first_nz (dist_v, - DDR_NB_LOOPS (ddr), 0)); - } - - if (dump_file && (dump_flags & TDF_DETAILS)) - { - unsigned i; - - fprintf (dump_file, "(build_classic_dist_vector\n"); - for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++) - { - fprintf (dump_file, " dist_vector = ("); - print_lambda_vector (dump_file, DDR_DIST_VECT (ddr, i), - DDR_NB_LOOPS (ddr)); - fprintf (dump_file, " )\n"); - } - fprintf (dump_file, ")\n"); - } - - return true; -} - -/* Return the direction for a given distance. - FIXME: Computing dir this way is suboptimal, since dir can catch - cases that dist is unable to represent. */ - -static inline enum data_dependence_direction -dir_from_dist (int dist) -{ - if (dist > 0) - return dir_positive; - else if (dist < 0) - return dir_negative; - else - return dir_equal; -} - -/* Compute the classic per loop direction vector. DDR is the data - dependence relation to build a vector from. */ - -static void -build_classic_dir_vector (struct data_dependence_relation *ddr) -{ - unsigned i, j; - lambda_vector dist_v; - - for (i = 0; VEC_iterate (lambda_vector, DDR_DIST_VECTS (ddr), i, dist_v); i++) - { - lambda_vector dir_v = lambda_vector_new (DDR_NB_LOOPS (ddr)); - - for (j = 0; j < DDR_NB_LOOPS (ddr); j++) - dir_v[j] = dir_from_dist (dist_v[j]); - - save_dir_v (ddr, dir_v); - } -} - -/* Helper function. Returns true when there is a dependence between - data references DRA and DRB. */ - -static bool -subscript_dependence_tester_1 (struct data_dependence_relation *ddr, - struct data_reference *dra, - struct data_reference *drb) -{ - unsigned int i; - tree last_conflicts; - struct subscript *subscript; - - for (i = 0; VEC_iterate (subscript_p, DDR_SUBSCRIPTS (ddr), i, subscript); - i++) - { - tree overlaps_a, overlaps_b; - - analyze_overlapping_iterations (DR_ACCESS_FN (dra, i), - DR_ACCESS_FN (drb, i), - &overlaps_a, &overlaps_b, - &last_conflicts); - - if (chrec_contains_undetermined (overlaps_a) - || chrec_contains_undetermined (overlaps_b)) - { - finalize_ddr_dependent (ddr, chrec_dont_know); - dependence_stats.num_dependence_undetermined++; - return false; - } - - else if (overlaps_a == chrec_known - || overlaps_b == chrec_known) - { - finalize_ddr_dependent (ddr, chrec_known); - dependence_stats.num_dependence_independent++; - return false; - } - - else - { - SUB_CONFLICTS_IN_A (subscript) = overlaps_a; - SUB_CONFLICTS_IN_B (subscript) = overlaps_b; - SUB_LAST_CONFLICT (subscript) = last_conflicts; - } - } - - return true; -} - -/* Computes the conflicting iterations, and initialize DDR. */ - -static void -subscript_dependence_tester (struct data_dependence_relation *ddr) -{ - - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "(subscript_dependence_tester \n"); - - if (subscript_dependence_tester_1 (ddr, DDR_A (ddr), DDR_B (ddr))) - dependence_stats.num_dependence_dependent++; - - compute_subscript_distance (ddr); - if (build_classic_dist_vector (ddr)) - build_classic_dir_vector (ddr); - - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, ")\n"); -} - -/* Returns true when all the access functions of A are affine or - constant. */ - -static bool -access_functions_are_affine_or_constant_p (struct data_reference *a) -{ - unsigned int i; - VEC(tree,heap) **fns = DR_ACCESS_FNS_ADDR (a); - tree t; - - for (i = 0; VEC_iterate (tree, *fns, i, t); i++) - if (!evolution_function_is_constant_p (t) - && !evolution_function_is_affine_multivariate_p (t)) - return false; - - return true; -} - -/* This computes the affine dependence relation between A and B. - CHREC_KNOWN is used for representing the independence between two - accesses, while CHREC_DONT_KNOW is used for representing the unknown - relation. - - Note that it is possible to stop the computation of the dependence - relation the first time we detect a CHREC_KNOWN element for a given - subscript. */ - -static void -compute_affine_dependence (struct data_dependence_relation *ddr) -{ - struct data_reference *dra = DDR_A (ddr); - struct data_reference *drb = DDR_B (ddr); - - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "(compute_affine_dependence\n"); - fprintf (dump_file, " (stmt_a = \n"); - print_generic_expr (dump_file, DR_STMT (dra), 0); - fprintf (dump_file, ")\n (stmt_b = \n"); - print_generic_expr (dump_file, DR_STMT (drb), 0); - fprintf (dump_file, ")\n"); - } - - /* Analyze only when the dependence relation is not yet known. */ - if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE) - { - dependence_stats.num_dependence_tests++; - - if (access_functions_are_affine_or_constant_p (dra) - && access_functions_are_affine_or_constant_p (drb)) - subscript_dependence_tester (ddr); - - /* As a last case, if the dependence cannot be determined, or if - the dependence is considered too difficult to determine, answer - "don't know". */ - else - { - dependence_stats.num_dependence_undetermined++; - - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "Data ref a:\n"); - dump_data_reference (dump_file, dra); - fprintf (dump_file, "Data ref b:\n"); - dump_data_reference (dump_file, drb); - fprintf (dump_file, "affine dependence test not usable: access function not affine or constant.\n"); - } - finalize_ddr_dependent (ddr, chrec_dont_know); - } - } - - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, ")\n"); -} - -/* This computes the dependence relation for the same data - reference into DDR. */ - -static void -compute_self_dependence (struct data_dependence_relation *ddr) -{ - unsigned int i; - struct subscript *subscript; - - for (i = 0; VEC_iterate (subscript_p, DDR_SUBSCRIPTS (ddr), i, subscript); - i++) - { - /* The accessed index overlaps for each iteration. */ - SUB_CONFLICTS_IN_A (subscript) = integer_zero_node; - SUB_CONFLICTS_IN_B (subscript) = integer_zero_node; - SUB_LAST_CONFLICT (subscript) = chrec_dont_know; - } - - /* The distance vector is the zero vector. */ - save_dist_v (ddr, lambda_vector_new (DDR_NB_LOOPS (ddr))); - save_dir_v (ddr, lambda_vector_new (DDR_NB_LOOPS (ddr))); -} - -/* Compute in DEPENDENCE_RELATIONS the data dependence graph for all - the data references in DATAREFS, in the LOOP_NEST. When - COMPUTE_SELF_AND_RR is FALSE, don't compute read-read and self - relations. */ - -static void -compute_all_dependences (VEC (data_reference_p, heap) *datarefs, - VEC (ddr_p, heap) **dependence_relations, - VEC (loop_p, heap) *loop_nest, - bool compute_self_and_rr) -{ - struct data_dependence_relation *ddr; - struct data_reference *a, *b; - unsigned int i, j; - - for (i = 0; VEC_iterate (data_reference_p, datarefs, i, a); i++) - for (j = i + 1; VEC_iterate (data_reference_p, datarefs, j, b); j++) - if (!DR_IS_READ (a) || !DR_IS_READ (b) || compute_self_and_rr) - { - ddr = initialize_data_dependence_relation (a, b, loop_nest); - VEC_safe_push (ddr_p, heap, *dependence_relations, ddr); - compute_affine_dependence (ddr); - } - - if (compute_self_and_rr) - for (i = 0; VEC_iterate (data_reference_p, datarefs, i, a); i++) - { - ddr = initialize_data_dependence_relation (a, a, loop_nest); - VEC_safe_push (ddr_p, heap, *dependence_relations, ddr); - compute_self_dependence (ddr); - } -} - -/* Search the data references in LOOP, and record the information into - DATAREFS. Returns chrec_dont_know when failing to analyze a - difficult case, returns NULL_TREE otherwise. - - TODO: This function should be made smarter so that it can handle address - arithmetic as if they were array accesses, etc. */ - -tree -find_data_references_in_loop (struct loop *loop, - VEC (data_reference_p, heap) **datarefs) -{ - basic_block bb, *bbs; - unsigned int i; - block_stmt_iterator bsi; - struct data_reference *dr; - - bbs = get_loop_body (loop); - - for (i = 0; i < loop->num_nodes; i++) - { - bb = bbs[i]; - - for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) - { - tree stmt = bsi_stmt (bsi); - - /* ASM_EXPR and CALL_EXPR may embed arbitrary side effects. - Calls have side-effects, except those to const or pure - functions. */ - if ((TREE_CODE (stmt) == CALL_EXPR - && !(call_expr_flags (stmt) & (ECF_CONST | ECF_PURE))) - || (TREE_CODE (stmt) == ASM_EXPR - && ASM_VOLATILE_P (stmt))) - goto insert_dont_know_node; - - if (ZERO_SSA_OPERANDS (stmt, SSA_OP_ALL_VIRTUALS)) - continue; - - switch (TREE_CODE (stmt)) - { - case MODIFY_EXPR: - { - bool one_inserted = false; - tree opnd0 = TREE_OPERAND (stmt, 0); - tree opnd1 = TREE_OPERAND (stmt, 1); - - if (TREE_CODE (opnd0) == ARRAY_REF - || TREE_CODE (opnd0) == INDIRECT_REF - || TREE_CODE (opnd0) == COMPONENT_REF) - { - dr = create_data_ref (opnd0, stmt, false); - if (dr) - { - VEC_safe_push (data_reference_p, heap, *datarefs, dr); - one_inserted = true; - } - } - - if (TREE_CODE (opnd1) == ARRAY_REF - || TREE_CODE (opnd1) == INDIRECT_REF - || TREE_CODE (opnd1) == COMPONENT_REF) - { - dr = create_data_ref (opnd1, stmt, true); - if (dr) - { - VEC_safe_push (data_reference_p, heap, *datarefs, dr); - one_inserted = true; - } - } - - if (!one_inserted) - goto insert_dont_know_node; - - break; - } - - case CALL_EXPR: - { - tree args; - bool one_inserted = false; - - for (args = TREE_OPERAND (stmt, 1); args; - args = TREE_CHAIN (args)) - if (TREE_CODE (TREE_VALUE (args)) == ARRAY_REF - || TREE_CODE (TREE_VALUE (args)) == INDIRECT_REF - || TREE_CODE (TREE_VALUE (args)) == COMPONENT_REF) - { - dr = create_data_ref (TREE_VALUE (args), stmt, true); - if (dr) - { - VEC_safe_push (data_reference_p, heap, *datarefs, dr); - one_inserted = true; - } - } - - if (!one_inserted) - goto insert_dont_know_node; - - break; - } - - default: - { - struct data_reference *res; - - insert_dont_know_node:; - res = XNEW (struct data_reference); - DR_STMT (res) = NULL_TREE; - DR_REF (res) = NULL_TREE; - DR_BASE_OBJECT (res) = NULL; - DR_TYPE (res) = ARRAY_REF_TYPE; - DR_SET_ACCESS_FNS (res, NULL); - DR_BASE_OBJECT (res) = NULL; - DR_IS_READ (res) = false; - DR_BASE_ADDRESS (res) = NULL_TREE; - DR_OFFSET (res) = NULL_TREE; - DR_INIT (res) = NULL_TREE; - DR_STEP (res) = NULL_TREE; - DR_OFFSET_MISALIGNMENT (res) = NULL_TREE; - DR_MEMTAG (res) = NULL_TREE; - DR_PTR_INFO (res) = NULL; - VEC_safe_push (data_reference_p, heap, *datarefs, res); - - free (bbs); - return chrec_dont_know; - } - } - - /* When there are no defs in the loop, the loop is parallel. */ - if (!ZERO_SSA_OPERANDS (stmt, SSA_OP_VIRTUAL_DEFS)) - loop->parallel_p = false; - } - } - - free (bbs); - - return NULL_TREE; -} - -/* Recursive helper function. */ - -static bool -find_loop_nest_1 (struct loop *loop, VEC (loop_p, heap) **loop_nest) -{ - /* Inner loops of the nest should not contain siblings. Example: - when there are two consecutive loops, - - | loop_0 - | loop_1 - | A[{0, +, 1}_1] - | endloop_1 - | loop_2 - | A[{0, +, 1}_2] - | endloop_2 - | endloop_0 - - the dependence relation cannot be captured by the distance - abstraction. */ - if (loop->next) - return false; - - VEC_safe_push (loop_p, heap, *loop_nest, loop); - if (loop->inner) - return find_loop_nest_1 (loop->inner, loop_nest); - return true; -} - -/* Return false when the LOOP is not well nested. Otherwise return - true and insert in LOOP_NEST the loops of the nest. LOOP_NEST will - contain the loops from the outermost to the innermost, as they will - appear in the classic distance vector. */ - -static bool -find_loop_nest (struct loop *loop, VEC (loop_p, heap) **loop_nest) -{ - VEC_safe_push (loop_p, heap, *loop_nest, loop); - if (loop->inner) - return find_loop_nest_1 (loop->inner, loop_nest); - return true; -} - -/* Given a loop nest LOOP, the following vectors are returned: - DATAREFS is initialized to all the array elements contained in this loop, - DEPENDENCE_RELATIONS contains the relations between the data references. - Compute read-read and self relations if - COMPUTE_SELF_AND_READ_READ_DEPENDENCES is TRUE. */ - -void -compute_data_dependences_for_loop (struct loop *loop, - bool compute_self_and_read_read_dependences, - VEC (data_reference_p, heap) **datarefs, - VEC (ddr_p, heap) **dependence_relations) -{ - struct loop *loop_nest = loop; - VEC (loop_p, heap) *vloops = VEC_alloc (loop_p, heap, 3); - - memset (&dependence_stats, 0, sizeof (dependence_stats)); - - /* If the loop nest is not well formed, or one of the data references - is not computable, give up without spending time to compute other - dependences. */ - if (!loop_nest - || !find_loop_nest (loop_nest, &vloops) - || find_data_references_in_loop (loop, datarefs) == chrec_dont_know) - { - struct data_dependence_relation *ddr; - - /* Insert a single relation into dependence_relations: - chrec_dont_know. */ - ddr = initialize_data_dependence_relation (NULL, NULL, vloops); - VEC_safe_push (ddr_p, heap, *dependence_relations, ddr); - } - else - compute_all_dependences (*datarefs, dependence_relations, vloops, - compute_self_and_read_read_dependences); - - if (dump_file && (dump_flags & TDF_STATS)) - { - fprintf (dump_file, "Dependence tester statistics:\n"); - - fprintf (dump_file, "Number of dependence tests: %d\n", - dependence_stats.num_dependence_tests); - fprintf (dump_file, "Number of dependence tests classified dependent: %d\n", - dependence_stats.num_dependence_dependent); - fprintf (dump_file, "Number of dependence tests classified independent: %d\n", - dependence_stats.num_dependence_independent); - fprintf (dump_file, "Number of undetermined dependence tests: %d\n", - dependence_stats.num_dependence_undetermined); - - fprintf (dump_file, "Number of subscript tests: %d\n", - dependence_stats.num_subscript_tests); - fprintf (dump_file, "Number of undetermined subscript tests: %d\n", - dependence_stats.num_subscript_undetermined); - fprintf (dump_file, "Number of same subscript function: %d\n", - dependence_stats.num_same_subscript_function); - - fprintf (dump_file, "Number of ziv tests: %d\n", - dependence_stats.num_ziv); - fprintf (dump_file, "Number of ziv tests returning dependent: %d\n", - dependence_stats.num_ziv_dependent); - fprintf (dump_file, "Number of ziv tests returning independent: %d\n", - dependence_stats.num_ziv_independent); - fprintf (dump_file, "Number of ziv tests unimplemented: %d\n", - dependence_stats.num_ziv_unimplemented); - - fprintf (dump_file, "Number of siv tests: %d\n", - dependence_stats.num_siv); - fprintf (dump_file, "Number of siv tests returning dependent: %d\n", - dependence_stats.num_siv_dependent); - fprintf (dump_file, "Number of siv tests returning independent: %d\n", - dependence_stats.num_siv_independent); - fprintf (dump_file, "Number of siv tests unimplemented: %d\n", - dependence_stats.num_siv_unimplemented); - - fprintf (dump_file, "Number of miv tests: %d\n", - dependence_stats.num_miv); - fprintf (dump_file, "Number of miv tests returning dependent: %d\n", - dependence_stats.num_miv_dependent); - fprintf (dump_file, "Number of miv tests returning independent: %d\n", - dependence_stats.num_miv_independent); - fprintf (dump_file, "Number of miv tests unimplemented: %d\n", - dependence_stats.num_miv_unimplemented); - } -} - -/* Entry point (for testing only). Analyze all the data references - and the dependence relations. - - The data references are computed first. - - A relation on these nodes is represented by a complete graph. Some - of the relations could be of no interest, thus the relations can be - computed on demand. - - In the following function we compute all the relations. This is - just a first implementation that is here for: - - for showing how to ask for the dependence relations, - - for the debugging the whole dependence graph, - - for the dejagnu testcases and maintenance. - - It is possible to ask only for a part of the graph, avoiding to - compute the whole dependence graph. The computed dependences are - stored in a knowledge base (KB) such that later queries don't - recompute the same information. The implementation of this KB is - transparent to the optimizer, and thus the KB can be changed with a - more efficient implementation, or the KB could be disabled. */ -#if 0 -static void -analyze_all_data_dependences (struct loops *loops) -{ - unsigned int i; - int nb_data_refs = 10; - VEC (data_reference_p, heap) *datarefs = - VEC_alloc (data_reference_p, heap, nb_data_refs); - VEC (ddr_p, heap) *dependence_relations = - VEC_alloc (ddr_p, heap, nb_data_refs * nb_data_refs); - - /* Compute DDs on the whole function. */ - compute_data_dependences_for_loop (loops->parray[0], false, - &datarefs, &dependence_relations); - - if (dump_file) - { - dump_data_dependence_relations (dump_file, dependence_relations); - fprintf (dump_file, "\n\n"); - - if (dump_flags & TDF_DETAILS) - dump_dist_dir_vectors (dump_file, dependence_relations); - - if (dump_flags & TDF_STATS) - { - unsigned nb_top_relations = 0; - unsigned nb_bot_relations = 0; - unsigned nb_basename_differ = 0; - unsigned nb_chrec_relations = 0; - struct data_dependence_relation *ddr; - - for (i = 0; VEC_iterate (ddr_p, dependence_relations, i, ddr); i++) - { - if (chrec_contains_undetermined (DDR_ARE_DEPENDENT (ddr))) - nb_top_relations++; - - else if (DDR_ARE_DEPENDENT (ddr) == chrec_known) - { - struct data_reference *a = DDR_A (ddr); - struct data_reference *b = DDR_B (ddr); - bool differ_p; - - if ((DR_BASE_OBJECT (a) && DR_BASE_OBJECT (b) - && DR_NUM_DIMENSIONS (a) != DR_NUM_DIMENSIONS (b)) - || (base_object_differ_p (a, b, &differ_p) - && differ_p)) - nb_basename_differ++; - else - nb_bot_relations++; - } - - else - nb_chrec_relations++; - } - - gather_stats_on_scev_database (); - } - } - - free_dependence_relations (dependence_relations); - free_data_refs (datarefs); -} -#endif - -/* Free the memory used by a data dependence relation DDR. */ - -void -free_dependence_relation (struct data_dependence_relation *ddr) -{ - if (ddr == NULL) - return; - - if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE && DDR_SUBSCRIPTS (ddr)) - VEC_free (subscript_p, heap, DDR_SUBSCRIPTS (ddr)); - - free (ddr); -} - -/* Free the memory used by the data dependence relations from - DEPENDENCE_RELATIONS. */ - -void -free_dependence_relations (VEC (ddr_p, heap) *dependence_relations) -{ - unsigned int i; - struct data_dependence_relation *ddr; - VEC (loop_p, heap) *loop_nest = NULL; - - for (i = 0; VEC_iterate (ddr_p, dependence_relations, i, ddr); i++) - { - if (ddr == NULL) - continue; - if (loop_nest == NULL) - loop_nest = DDR_LOOP_NEST (ddr); - else - gcc_assert (DDR_LOOP_NEST (ddr) == NULL - || DDR_LOOP_NEST (ddr) == loop_nest); - free_dependence_relation (ddr); - } - - if (loop_nest) - VEC_free (loop_p, heap, loop_nest); - VEC_free (ddr_p, heap, dependence_relations); -} - -/* Free the memory used by the data references from DATAREFS. */ - -void -free_data_refs (VEC (data_reference_p, heap) *datarefs) -{ - unsigned int i; - struct data_reference *dr; - - for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++) - free_data_ref (dr); - VEC_free (data_reference_p, heap, datarefs); -} - |