/* Data references and dependences detectors.
- Copyright (C) 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
+ Copyright (C) 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
Contributed by Sebastian Pop <pop@cri.ensmp.fr>
This file is part of GCC.
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 *);
if (pi)
tag = pi->name_mem_tag;
if (!tag)
- tag = get_var_ann (SSA_NAME_VAR (ptr))->symbol_mem_tag;
+ tag = symbol_mem_tag (SSA_NAME_VAR (ptr));
if (!tag)
tag = DR_MEMTAG (ptr_dr);
if (!tag)
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);
+ bitmap bal1, bal2;
if (pi_a && pi_a->name_mem_tag && pi_b && pi_b->name_mem_tag)
{
}
else
{
- tag_a = get_var_ann (SSA_NAME_VAR (ptr_a))->symbol_mem_tag;
+ tag_a = symbol_mem_tag (SSA_NAME_VAR (ptr_a));
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;
+ tag_b = symbol_mem_tag (SSA_NAME_VAR (ptr_b));
if (!tag_b)
tag_b = DR_MEMTAG (drb);
if (!tag_b)
return false;
}
- *aliased = (tag_a == tag_b);
+ bal1 = BITMAP_ALLOC (NULL);
+ bitmap_set_bit (bal1, DECL_UID (tag_a));
+ if (MTAG_P (tag_a) && MTAG_ALIASES (tag_a))
+ bitmap_ior_into (bal1, MTAG_ALIASES (tag_a));
+
+ bal2 = BITMAP_ALLOC (NULL);
+ bitmap_set_bit (bal2, DECL_UID (tag_b));
+ if (MTAG_P (tag_b) && MTAG_ALIASES (tag_b))
+ bitmap_ior_into (bal2, MTAG_ALIASES (tag_b));
+ *aliased = bitmap_intersect_p (bal1, bal2);
+
+ BITMAP_FREE (bal1);
+ BITMAP_FREE (bal2);
return true;
}
tree addr_a = DR_BASE_ADDRESS (dra);
tree addr_b = DR_BASE_ADDRESS (drb);
tree type_a, type_b;
+ tree decl_a, decl_b;
bool aliased;
if (!addr_a || !addr_b)
}
/* 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)))
+ instruction reading or writing through a different restricted pointer,
+ in the same block/scope. */
+ else if (TYPE_RESTRICT (type_a)
+ && TYPE_RESTRICT (type_b)
+ && (!DR_IS_READ (drb) || !DR_IS_READ (dra))
+ && TREE_CODE (DR_BASE_ADDRESS (dra)) == SSA_NAME
+ && (decl_a = SSA_NAME_VAR (DR_BASE_ADDRESS (dra)))
+ && TREE_CODE (decl_a) == PARM_DECL
+ && TREE_CODE (DECL_CONTEXT (decl_a)) == FUNCTION_DECL
+ && TREE_CODE (DR_BASE_ADDRESS (drb)) == SSA_NAME
+ && (decl_b = SSA_NAME_VAR (DR_BASE_ADDRESS (drb)))
+ && TREE_CODE (decl_b) == PARM_DECL
+ && TREE_CODE (DECL_CONTEXT (decl_b)) == FUNCTION_DECL
+ && DECL_CONTEXT (decl_a) == DECL_CONTEXT (decl_b))
{
*differ_p = true;
return true;
}
+
return false;
}
/* Returns true iff A divides B. */
static inline bool
-tree_fold_divides_p (tree a,
- tree b)
+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));
+ gcc_assert (TREE_CODE (a) == INTEGER_CST);
+ gcc_assert (TREE_CODE (b) == INTEGER_CST);
+ return integer_zerop (int_const_binop (TRUNC_MOD_EXPR, b, a, 0));
}
/* Returns true iff A divides B. */
fprintf (outf, ")\n");
}
+/* Dumps the affine function described by FN to the file OUTF. */
+
+static void
+dump_affine_function (FILE *outf, affine_fn fn)
+{
+ unsigned i;
+ tree coef;
+
+ print_generic_expr (outf, VEC_index (tree, fn, 0), TDF_SLIM);
+ for (i = 1; VEC_iterate (tree, fn, i, coef); i++)
+ {
+ fprintf (outf, " + ");
+ print_generic_expr (outf, coef, TDF_SLIM);
+ fprintf (outf, " * x_%u", i);
+ }
+}
+
+/* Dumps the conflict function CF to the file OUTF. */
+
+static void
+dump_conflict_function (FILE *outf, conflict_function *cf)
+{
+ unsigned i;
+
+ if (cf->n == NO_DEPENDENCE)
+ fprintf (outf, "no dependence\n");
+ else if (cf->n == NOT_KNOWN)
+ fprintf (outf, "not known\n");
+ else
+ {
+ for (i = 0; i < cf->n; i++)
+ {
+ fprintf (outf, "[");
+ dump_affine_function (outf, cf->fns[i]);
+ fprintf (outf, "]\n");
+ }
+ }
+}
+
/* Dump function for a SUBSCRIPT structure. */
void
dump_subscript (FILE *outf, struct subscript *subscript)
{
- tree chrec = SUB_CONFLICTS_IN_A (subscript);
+ conflict_function *cf = 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
+ dump_conflict_function (outf, cf);
+ if (CF_NONTRIVIAL_P (cf))
{
tree last_iteration = SUB_LAST_CONFLICT (subscript);
fprintf (outf, " last_conflict: ");
print_generic_stmt (outf, last_iteration, 0);
}
- chrec = SUB_CONFLICTS_IN_B (subscript);
+ cf = 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
+ dump_conflict_function (outf, cf);
+ if (CF_NONTRIVIAL_P (cf))
{
tree last_iteration = SUB_LAST_CONFLICT (subscript);
fprintf (outf, " last_conflict: ");
dump_subscript (outf, DDR_SUBSCRIPT (ddr, i));
}
+ fprintf (outf, " inner loop index: %d\n", DDR_INNER_LOOP (ddr));
fprintf (outf, " loop nest: (");
for (i = 0; VEC_iterate (loop_p, DDR_LOOP_NEST (ddr), i, loopi); i++)
fprintf (outf, "%d ", loopi->num);
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)
+static struct data_reference *
+init_array_ref (tree stmt, tree ref, bool is_read)
{
- struct data_reference *res;
- VEC(tree,heap) *acc_fns;
+ struct loop *loop = loop_containing_stmt (stmt);
+ VEC(tree,heap) *acc_fns = VEC_alloc (tree, heap, 3);
+ struct data_reference *res = XNEW (struct data_reference);;
if (dump_file && (dump_flags & TDF_DETAILS))
{
- fprintf (dump_file, "(analyze_array \n");
+ fprintf (dump_file, "(init_array_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;
- acc_fns = VEC_alloc (tree, heap, 3);
- DR_BASE_OBJECT (res) = analyze_array_indexes
- (loop_containing_stmt (stmt), &acc_fns, ref, stmt);
+ DR_BASE_OBJECT (res) = analyze_array_indexes (loop, &acc_fns, ref, stmt);
DR_TYPE (res) = ARRAY_REF_TYPE;
DR_SET_ACCESS_FNS (res, acc_fns);
DR_IS_READ (res) = is_read;
return res;
}
+/* For a data reference REF contained in the statement STMT, initialize
+ a DATA_REFERENCE structure, and return it. */
+
+static struct data_reference *
+init_pointer_ref (tree stmt, tree ref, tree access_fn, bool is_read,
+ tree base_address, tree step, struct ptr_info_def *ptr_info)
+{
+ struct data_reference *res = XNEW (struct data_reference);
+ VEC(tree,heap) *acc_fns = VEC_alloc (tree, heap, 3);
+
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ {
+ fprintf (dump_file, "(init_pointer_ref \n");
+ fprintf (dump_file, " (ref = ");
+ print_generic_stmt (dump_file, ref, 0);
+ fprintf (dump_file, ")\n");
+ }
+
+ DR_STMT (res) = stmt;
+ DR_REF (res) = ref;
+ DR_BASE_OBJECT (res) = NULL_TREE;
+ DR_TYPE (res) = POINTER_REF_TYPE;
+ 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) = NULL_TREE;
+ DR_INIT (res) = NULL_TREE;
+ DR_STEP (res) = step;
+ DR_OFFSET_MISALIGNMENT (res) = NULL_TREE;
+ DR_MEMTAG (res) = NULL_TREE;
+ DR_PTR_INFO (res) = ptr_info;
+
+ 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.
if (!expr_invariant_in_loop_p (loop, init))
{
- if (dump_file && (dump_flags & TDF_DETAILS))
+ if (dump_file && (dump_flags & TDF_DETAILS))
fprintf (dump_file, "\ninitial condition is not loop invariant.\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;
+ return init_pointer_ref (stmt, ref, access_fn, is_read, base_address,
+ step, ptr_info);
}
/* Function strip_conversions
if (!(*dr))
{
if (TREE_CODE (memref) == ARRAY_REF)
- *dr = analyze_array (stmt, memref, is_read);
+ *dr = init_array_ref (stmt, memref, is_read);
else if (TREE_CODE (memref) == COMPONENT_REF)
comp_ref = memref;
else
{
if (comp_ref && TREE_CODE (TREE_OPERAND (comp_ref, 0)) == ARRAY_REF)
{
- *dr = analyze_array (stmt, TREE_OPERAND (comp_ref, 0), is_read);
+ *dr = init_array_ref (stmt, TREE_OPERAND (comp_ref, 0), is_read);
if (DR_NUM_DIMENSIONS (*dr) != 1)
{
if (dump_file && (dump_flags & TDF_DETAILS))
switch (TREE_CODE (base_address))
{
case SSA_NAME:
- *memtag = get_var_ann (SSA_NAME_VAR (base_address))->symbol_mem_tag;
+ *memtag = symbol_mem_tag (SSA_NAME_VAR (base_address));
if (!(*memtag) && TREE_CODE (TREE_OPERAND (memref, 0)) == SSA_NAME)
- *memtag = get_var_ann (
- SSA_NAME_VAR (TREE_OPERAND (memref, 0)))->symbol_mem_tag;
+ *memtag = symbol_mem_tag (SSA_NAME_VAR (TREE_OPERAND (memref, 0)));
break;
case ADDR_EXPR:
*memtag = TREE_OPERAND (base_address, 0);
Extract INVARIANT and CONSTANT parts from OFFSET.
*/
-static void
+static bool
analyze_offset (tree offset, tree *invariant, tree *constant)
{
tree op0, op1, constant_0, constant_1, invariant_0, invariant_1;
*constant = offset;
else
*invariant = offset;
- return;
+ return true;
}
op0 = TREE_OPERAND (offset, 0);
op1 = TREE_OPERAND (offset, 1);
/* Recursive call with the operands. */
- analyze_offset (op0, &invariant_0, &constant_0);
- analyze_offset (op1, &invariant_1, &constant_1);
+ if (!analyze_offset (op0, &invariant_0, &constant_0)
+ || !analyze_offset (op1, &invariant_1, &constant_1))
+ return false;
- /* Combine the results. */
+ /* 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;
+ {
+ *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. */
STRIP_NOPS (offset);
if (offset != orig_offset)
type = TREE_TYPE (orig_offset);
- analyze_offset (offset, &invariant, &constant);
+ 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);
return dr;
}
+/* Returns true if FNA == FNB. */
+
+static bool
+affine_function_equal_p (affine_fn fna, affine_fn fnb)
+{
+ unsigned i, n = VEC_length (tree, fna);
+
+ if (n != VEC_length (tree, fnb))
+ return false;
+
+ for (i = 0; i < n; i++)
+ if (!operand_equal_p (VEC_index (tree, fna, i),
+ VEC_index (tree, fnb, i), 0))
+ return false;
+
+ return true;
+}
+
+/* If all the functions in CF are the same, returns one of them,
+ otherwise returns NULL. */
-/* Returns true when all the functions of a tree_vec CHREC are the
- same. */
+static affine_fn
+common_affine_function (conflict_function *cf)
+{
+ unsigned i;
+ affine_fn comm;
-static bool
-all_chrecs_equal_p (tree chrec)
+ if (!CF_NONTRIVIAL_P (cf))
+ return NULL;
+
+ comm = cf->fns[0];
+
+ for (i = 1; i < cf->n; i++)
+ if (!affine_function_equal_p (comm, cf->fns[i]))
+ return NULL;
+
+ return comm;
+}
+
+/* Returns the base of the affine function FN. */
+
+static tree
+affine_function_base (affine_fn fn)
+{
+ return VEC_index (tree, fn, 0);
+}
+
+/* Returns true if FN is a constant. */
+
+static bool
+affine_function_constant_p (affine_fn fn)
{
- int j;
+ unsigned i;
+ tree coef;
- 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)))
+ for (i = 1; VEC_iterate (tree, fn, i, coef); i++)
+ if (!integer_zerop (coef))
return false;
return true;
}
+/* Returns true if FN is the zero constant function. */
+
+static bool
+affine_function_zero_p (affine_fn fn)
+{
+ return (integer_zerop (affine_function_base (fn))
+ && affine_function_constant_p (fn));
+}
+
+/* Applies operation OP on affine functions FNA and FNB, and returns the
+ result. */
+
+static affine_fn
+affine_fn_op (enum tree_code op, affine_fn fna, affine_fn fnb)
+{
+ unsigned i, n, m;
+ affine_fn ret;
+ tree coef;
+
+ if (VEC_length (tree, fnb) > VEC_length (tree, fna))
+ {
+ n = VEC_length (tree, fna);
+ m = VEC_length (tree, fnb);
+ }
+ else
+ {
+ n = VEC_length (tree, fnb);
+ m = VEC_length (tree, fna);
+ }
+
+ ret = VEC_alloc (tree, heap, m);
+ for (i = 0; i < n; i++)
+ VEC_quick_push (tree, ret,
+ fold_build2 (op, integer_type_node,
+ VEC_index (tree, fna, i),
+ VEC_index (tree, fnb, i)));
+
+ for (; VEC_iterate (tree, fna, i, coef); i++)
+ VEC_quick_push (tree, ret,
+ fold_build2 (op, integer_type_node,
+ coef, integer_zero_node));
+ for (; VEC_iterate (tree, fnb, i, coef); i++)
+ VEC_quick_push (tree, ret,
+ fold_build2 (op, integer_type_node,
+ integer_zero_node, coef));
+
+ return ret;
+}
+
+/* Returns the sum of affine functions FNA and FNB. */
+
+static affine_fn
+affine_fn_plus (affine_fn fna, affine_fn fnb)
+{
+ return affine_fn_op (PLUS_EXPR, fna, fnb);
+}
+
+/* Returns the difference of affine functions FNA and FNB. */
+
+static affine_fn
+affine_fn_minus (affine_fn fna, affine_fn fnb)
+{
+ return affine_fn_op (MINUS_EXPR, fna, fnb);
+}
+
+/* Frees affine function FN. */
+
+static void
+affine_fn_free (affine_fn fn)
+{
+ VEC_free (tree, heap, fn);
+}
+
/* Determine for each subscript in the data dependence relation DDR
the distance. */
static void
compute_subscript_distance (struct data_dependence_relation *ddr)
{
+ conflict_function *cf_a, *cf_b;
+ affine_fn fn_a, fn_b, diff;
+
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);
- }
+ cf_a = SUB_CONFLICTS_IN_A (subscript);
+ cf_b = SUB_CONFLICTS_IN_B (subscript);
- if (TREE_CODE (conflicts_b) == TREE_VEC)
+ fn_a = common_affine_function (cf_a);
+ fn_b = common_affine_function (cf_b);
+ if (!fn_a || !fn_b)
{
- if (!all_chrecs_equal_p (conflicts_b))
- {
- SUB_DISTANCE (subscript) = chrec_dont_know;
- return;
- }
- else
- conflicts_b = TREE_VEC_ELT (conflicts_b, 0);
+ SUB_DISTANCE (subscript) = chrec_dont_know;
+ return;
}
-
- 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;
+ diff = affine_fn_minus (fn_a, fn_b);
+ if (affine_function_constant_p (diff))
+ SUB_DISTANCE (subscript) = affine_function_base (diff);
else
SUB_DISTANCE (subscript) = chrec_dont_know;
+
+ affine_fn_free (diff);
}
}
}
+/* Returns the conflict function for "unknown". */
+
+static conflict_function *
+conflict_fn_not_known (void)
+{
+ conflict_function *fn = XCNEW (conflict_function);
+ fn->n = NOT_KNOWN;
+
+ return fn;
+}
+
+/* Returns the conflict function for "independent". */
+
+static conflict_function *
+conflict_fn_no_dependence (void)
+{
+ conflict_function *fn = XCNEW (conflict_function);
+ fn->n = NO_DEPENDENCE;
+
+ return fn;
+}
+
/* 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. */
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_INNER_LOOP (res) = 0;
DDR_DIR_VECTS (res) = NULL;
DDR_DIST_VECTS (res) = NULL;
struct subscript *subscript;
subscript = XNEW (struct subscript);
- SUB_CONFLICTS_IN_A (subscript) = chrec_dont_know;
- SUB_CONFLICTS_IN_B (subscript) = chrec_dont_know;
+ SUB_CONFLICTS_IN_A (subscript) = conflict_fn_not_known ();
+ SUB_CONFLICTS_IN_B (subscript) = conflict_fn_not_known ();
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;
}
+/* Frees memory used by the conflict function F. */
+
+static void
+free_conflict_function (conflict_function *f)
+{
+ unsigned i;
+
+ if (CF_NONTRIVIAL_P (f))
+ {
+ for (i = 0; i < f->n; i++)
+ affine_fn_free (f->fns[i]);
+ }
+ free (f);
+}
+
+/* Frees memory used by SUBSCRIPTS. */
+
+static void
+free_subscripts (VEC (subscript_p, heap) *subscripts)
+{
+ unsigned i;
+ subscript_p s;
+
+ for (i = 0; VEC_iterate (subscript_p, subscripts, i, s); i++)
+ {
+ free_conflict_function (s->conflicting_iterations_in_a);
+ free_conflict_function (s->conflicting_iterations_in_b);
+ }
+ VEC_free (subscript_p, heap, subscripts);
+}
+
/* Set DDR_ARE_DEPENDENT to CHREC and finalize the subscript overlap
description. */
}
DDR_ARE_DEPENDENT (ddr) = chrec;
- VEC_free (subscript_p, heap, DDR_SUBSCRIPTS (ddr));
+ free_subscripts (DDR_SUBSCRIPTS (ddr));
}
/* The dependence relation DDR cannot be represented by a distance
return false;
}
+/* Creates a conflict function with N dimensions. The affine functions
+ in each dimension follow. */
+
+static conflict_function *
+conflict_fn (unsigned n, ...)
+{
+ unsigned i;
+ conflict_function *ret = XCNEW (conflict_function);
+ va_list ap;
+
+ gcc_assert (0 < n && n <= MAX_DIM);
+ va_start(ap, n);
+
+ ret->n = n;
+ for (i = 0; i < n; i++)
+ ret->fns[i] = va_arg (ap, affine_fn);
+ va_end(ap);
+
+ return ret;
+}
+
+/* Returns constant affine function with value CST. */
+
+static affine_fn
+affine_fn_cst (tree cst)
+{
+ affine_fn fn = VEC_alloc (tree, heap, 1);
+ VEC_quick_push (tree, fn, cst);
+ return fn;
+}
+
+/* Returns affine function with single variable, CST + COEF * x_DIM. */
+
+static affine_fn
+affine_fn_univar (tree cst, unsigned dim, tree coef)
+{
+ affine_fn fn = VEC_alloc (tree, heap, dim + 1);
+ unsigned i;
+
+ gcc_assert (dim > 0);
+ VEC_quick_push (tree, fn, cst);
+ for (i = 1; i < dim; i++)
+ VEC_quick_push (tree, fn, integer_zero_node);
+ VEC_quick_push (tree, fn, coef);
+ return fn;
+}
+
/* 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
static void
analyze_ziv_subscript (tree chrec_a,
tree chrec_b,
- tree *overlaps_a,
- tree *overlaps_b,
+ conflict_function **overlaps_a,
+ conflict_function **overlaps_b,
tree *last_conflicts)
{
tree 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;
+ *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node));
+ *overlaps_b = conflict_fn (1, affine_fn_cst (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;
+ *overlaps_a = conflict_fn_no_dependence ();
+ *overlaps_b = conflict_fn_no_dependence ();
*last_conflicts = integer_zero_node;
dependence_stats.num_ziv_independent++;
}
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;
+ *overlaps_a = conflict_fn_not_known ();
+ *overlaps_b = conflict_fn_not_known ();
*last_conflicts = chrec_dont_know;
dependence_stats.num_ziv_unimplemented++;
break;
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. */
+/* Sets NIT to the estimated number of executions of the statements in
+ LOOP. If CONSERVATIVE is true, we must be sure that NIT is at least as
+ large as the number of iterations. If we have no reliable estimate,
+ the function returns false, otherwise returns true. */
-static tree
-get_number_of_iters_for_loop (int loopnum)
+bool
+estimated_loop_iterations (struct loop *loop, bool conservative,
+ double_int *nit)
{
- struct loop *loop = get_loop (loopnum);
- tree numiter = number_of_iterations_in_loop (loop);
-
- if (TREE_CODE (numiter) == INTEGER_CST)
- return numiter;
+ estimate_numbers_of_iterations_loop (loop);
+ if (conservative)
+ {
+ if (!loop->any_upper_bound)
+ return false;
- if (loop->estimate_state == EST_AVAILABLE)
+ *nit = loop->nb_iterations_upper_bound;
+ }
+ else
{
- tree type = lang_hooks.types.type_for_size (INT_TYPE_SIZE, true);
- if (double_int_fits_to_tree_p (type, loop->estimated_nb_iterations))
- return double_int_to_tree (type, loop->estimated_nb_iterations);
+ if (!loop->any_estimate)
+ return false;
+
+ *nit = loop->nb_iterations_estimate;
}
- return NULL_TREE;
+ return true;
}
-
-/* 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)). */
+/* Similar to estimated_loop_iterations, but returns the estimate only
+ if it fits to HOST_WIDE_INT. If this is not the case, or the estimate
+ on the number of iterations of LOOP could not be derived, returns -1. */
-static void
-analyze_siv_subscript_cst_affine (tree chrec_a,
- tree chrec_b,
- tree *overlaps_a,
- tree *overlaps_b,
- tree *last_conflicts)
+HOST_WIDE_INT
+estimated_loop_iterations_int (struct loop *loop, bool conservative)
{
- bool value0, value1, value2;
- tree difference;
+ double_int nit;
+ HOST_WIDE_INT hwi_nit;
+
+ if (!estimated_loop_iterations (loop, conservative, &nit))
+ return -1;
+
+ if (!double_int_fits_in_shwi_p (nit))
+ return -1;
+ hwi_nit = double_int_to_shwi (nit);
+
+ return hwi_nit < 0 ? -1 : hwi_nit;
+}
+
+/* Similar to estimated_loop_iterations, but returns the estimate as a tree,
+ and only if it fits to the int type. If this is not the case, or the
+ estimate on the number of iterations of LOOP could not be derived, returns
+ chrec_dont_know. */
+
+static tree
+estimated_loop_iterations_tree (struct loop *loop, bool conservative)
+{
+ double_int nit;
+ tree type;
+
+ if (!estimated_loop_iterations (loop, conservative, &nit))
+ return chrec_dont_know;
+
+ type = lang_hooks.types.type_for_size (INT_TYPE_SIZE, true);
+ if (!double_int_fits_to_tree_p (type, nit))
+ return chrec_dont_know;
+
+ return double_int_to_tree (type, nit);
+}
+
+/* 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,
+ conflict_function **overlaps_a,
+ conflict_function **overlaps_b,
+ tree *last_conflicts)
+{
+ bool value0, value1, value2;
+ tree difference, tmp;
chrec_a = chrec_convert (integer_type_node, chrec_a, NULL_TREE);
chrec_b = chrec_convert (integer_type_node, chrec_b, NULL_TREE);
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;
+ *overlaps_a = conflict_fn_not_known ();
+ *overlaps_b = conflict_fn_not_known ();
*last_conflicts = chrec_dont_know;
return;
}
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;
+ *overlaps_a = conflict_fn_not_known ();
+ *overlaps_b = conflict_fn_not_known ();
*last_conflicts = chrec_dont_know;
dependence_stats.num_siv_unimplemented++;
return;
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));
+ HOST_WIDE_INT numiter;
+ struct loop *loop = get_chrec_loop (chrec_b);
+
+ *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node));
+ tmp = fold_build2 (EXACT_DIV_EXPR, integer_type_node,
+ fold_build1 (ABS_EXPR,
+ integer_type_node,
+ difference),
+ CHREC_RIGHT (chrec_b));
+ *overlaps_b = conflict_fn (1, affine_fn_cst (tmp));
*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);
+ numiter = estimated_loop_iterations_int (loop, true);
- if (numiter != NULL_TREE
- && TREE_CODE (*overlaps_b) == INTEGER_CST
- && tree_int_cst_lt (numiter, *overlaps_b))
+ if (numiter >= 0
+ && compare_tree_int (tmp, numiter) > 0)
{
- *overlaps_a = chrec_known;
- *overlaps_b = chrec_known;
+ free_conflict_function (*overlaps_a);
+ free_conflict_function (*overlaps_b);
+ *overlaps_a = conflict_fn_no_dependence ();
+ *overlaps_b = conflict_fn_no_dependence ();
*last_conflicts = integer_zero_node;
dependence_stats.num_siv_independent++;
return;
no overlaps. */
else
{
- *overlaps_a = chrec_known;
- *overlaps_b = chrec_known;
+ *overlaps_a = conflict_fn_no_dependence ();
+ *overlaps_b = conflict_fn_no_dependence ();
*last_conflicts = integer_zero_node;
dependence_stats.num_siv_independent++;
return;
chrec_b = {10, +, -1}
In this case, chrec_a will not overlap with chrec_b. */
- *overlaps_a = chrec_known;
- *overlaps_b = chrec_known;
+ *overlaps_a = conflict_fn_no_dependence ();
+ *overlaps_b = conflict_fn_no_dependence ();
*last_conflicts = integer_zero_node;
dependence_stats.num_siv_independent++;
return;
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;
+ *overlaps_a = conflict_fn_not_known ();
+ *overlaps_b = conflict_fn_not_known ();
*last_conflicts = chrec_dont_know;
dependence_stats.num_siv_unimplemented++;
return;
*/
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));
+ HOST_WIDE_INT numiter;
+ struct loop *loop = get_chrec_loop (chrec_b);
+
+ *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node));
+ tmp = fold_build2 (EXACT_DIV_EXPR,
+ integer_type_node, difference,
+ CHREC_RIGHT (chrec_b));
+ *overlaps_b = conflict_fn (1, affine_fn_cst (tmp));
*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);
+ numiter = estimated_loop_iterations_int (loop, true);
- if (numiter != NULL_TREE
- && TREE_CODE (*overlaps_b) == INTEGER_CST
- && tree_int_cst_lt (numiter, *overlaps_b))
+ if (numiter >= 0
+ && compare_tree_int (tmp, numiter) > 0)
{
- *overlaps_a = chrec_known;
- *overlaps_b = chrec_known;
+ free_conflict_function (*overlaps_a);
+ free_conflict_function (*overlaps_b);
+ *overlaps_a = conflict_fn_no_dependence ();
+ *overlaps_b = conflict_fn_no_dependence ();
*last_conflicts = integer_zero_node;
dependence_stats.num_siv_independent++;
return;
are no overlaps. */
else
{
- *overlaps_a = chrec_known;
- *overlaps_b = chrec_known;
+ *overlaps_a = conflict_fn_no_dependence ();
+ *overlaps_b = conflict_fn_no_dependence ();
*last_conflicts = integer_zero_node;
dependence_stats.num_siv_independent++;
return;
chrec_b = {4, +, 1}
In this case, chrec_a will not overlap with chrec_b. */
- *overlaps_a = chrec_known;
- *overlaps_b = chrec_known;
+ *overlaps_a = conflict_fn_no_dependence ();
+ *overlaps_b = conflict_fn_no_dependence ();
*last_conflicts = integer_zero_node;
dependence_stats.num_siv_independent++;
return;
static void
compute_overlap_steps_for_affine_univar (int niter, int step_a, int step_b,
- tree *overlaps_a, tree *overlaps_b,
+ affine_fn *overlaps_a,
+ affine_fn *overlaps_b,
tree *last_conflicts, int dim)
{
if (((step_a > 0 && step_b > 0)
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));
+ *overlaps_a = affine_fn_univar (integer_zero_node, dim,
+ build_int_cst (NULL_TREE,
+ step_overlaps_a));
+ *overlaps_b = affine_fn_univar (integer_zero_node, dim,
+ 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;
+ *overlaps_a = affine_fn_cst (integer_zero_node);
+ *overlaps_b = affine_fn_cst (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,
static void
compute_overlap_steps_for_affine_1_2 (tree chrec_a, tree chrec_b,
- tree *overlaps_a, tree *overlaps_b,
+ conflict_function **overlaps_a,
+ conflict_function **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;
+ HOST_WIDE_INT niter_x, niter_y, niter_z, niter;
+ affine_fn overlaps_a_xz, overlaps_b_xz;
+ affine_fn overlaps_a_yz, overlaps_b_yz;
+ affine_fn overlaps_a_xyz, overlaps_b_xyz;
+ affine_fn ova1, ova2, ovb;
+ tree last_conflicts_xz, last_conflicts_yz, 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));
+ niter_x = estimated_loop_iterations_int
+ (get_chrec_loop (CHREC_LEFT (chrec_a)), true);
+ niter_y = estimated_loop_iterations_int (get_chrec_loop (chrec_a), true);
+ niter_z = estimated_loop_iterations_int (get_chrec_loop (chrec_b), true);
- if (numiter_x == NULL_TREE || numiter_y == NULL_TREE
- || numiter_z == NULL_TREE)
+ if (niter_x < 0 || niter_y < 0 || niter_z < 0)
{
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;
+ *overlaps_a = conflict_fn_not_known ();
+ *overlaps_b = conflict_fn_not_known ();
*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,
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;
+ ova1 = affine_fn_cst (integer_zero_node);
+ ova2 = affine_fn_cst (integer_zero_node);
+ ovb = affine_fn_cst (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);
+ affine_fn t0 = ova1;
+ affine_fn t2 = ovb;
+
+ ova1 = affine_fn_plus (ova1, overlaps_a_xz);
+ ovb = affine_fn_plus (ovb, overlaps_b_xz);
+ affine_fn_free (t0);
+ affine_fn_free (t2);
*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);
+ affine_fn t0 = ova2;
+ affine_fn t2 = ovb;
+
+ ova2 = affine_fn_plus (ova2, overlaps_a_yz);
+ ovb = affine_fn_plus (ovb, overlaps_b_yz);
+ affine_fn_free (t0);
+ affine_fn_free (t2);
*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);
+ affine_fn t0 = ova1;
+ affine_fn t2 = ova2;
+ affine_fn t4 = ovb;
+
+ ova1 = affine_fn_plus (ova1, overlaps_a_xyz);
+ ova2 = affine_fn_plus (ova2, overlaps_a_xyz);
+ ovb = affine_fn_plus (ovb, overlaps_b_xyz);
+ affine_fn_free (t0);
+ affine_fn_free (t2);
+ affine_fn_free (t4);
*last_conflicts = last_conflicts_xyz;
}
+ *overlaps_a = conflict_fn (2, ova1, ova2);
+ *overlaps_b = conflict_fn (1, ovb);
}
else
{
- *overlaps_a = integer_zero_node;
- *overlaps_b = integer_zero_node;
+ *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node));
+ *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node));
*last_conflicts = integer_zero_node;
}
+
+ affine_fn_free (overlaps_a_xz);
+ affine_fn_free (overlaps_b_xz);
+ affine_fn_free (overlaps_a_yz);
+ affine_fn_free (overlaps_b_yz);
+ affine_fn_free (overlaps_a_xyz);
+ affine_fn_free (overlaps_b_xyz);
}
/* Determines the overlapping elements due to accesses CHREC_A and
static void
analyze_subscript_affine_affine (tree chrec_a,
tree chrec_b,
- tree *overlaps_a,
- tree *overlaps_b,
+ conflict_function **overlaps_a,
+ conflict_function **overlaps_b,
tree *last_conflicts)
{
unsigned nb_vars_a, nb_vars_b, dim;
{
/* The accessed index overlaps for each iteration in the
loop. */
- *overlaps_a = integer_zero_node;
- *overlaps_b = integer_zero_node;
+ *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node));
+ *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node));
*last_conflicts = chrec_dont_know;
return;
}
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)
+ HOST_WIDE_INT niter, niter_a, niter_b;
+ affine_fn ova, ovb;
+
+ niter_a = estimated_loop_iterations_int
+ (get_chrec_loop (chrec_a), true);
+ niter_b = estimated_loop_iterations_int
+ (get_chrec_loop (chrec_b), true);
+ if (niter_a < 0 || niter_b < 0)
{
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;
+ *overlaps_a = conflict_fn_not_known ();
+ *overlaps_b = conflict_fn_not_known ();
*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,
+ &ova, &ovb,
last_conflicts, 1);
+ *overlaps_a = conflict_fn (1, ova);
+ *overlaps_b = conflict_fn (1, ovb);
}
else if (nb_vars_a == 2 && nb_vars_b == 1)
{
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;
+ *overlaps_a = conflict_fn_not_known ();
+ *overlaps_b = conflict_fn_not_known ();
*last_conflicts = chrec_dont_know;
}
goto end_analyze_subs_aa;
don't know. */
if (gcd_alpha_beta == 0)
{
- *overlaps_a = chrec_dont_know;
- *overlaps_b = chrec_dont_know;
+ *overlaps_a = conflict_fn_not_known ();
+ *overlaps_b = conflict_fn_not_known ();
*last_conflicts = chrec_dont_know;
goto end_analyze_subs_aa;
}
{
/* 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;
+ *overlaps_a = conflict_fn_no_dependence ();
+ *overlaps_b = conflict_fn_no_dependence ();
*last_conflicts = integer_zero_node;
}
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));
+ niter_a = estimated_loop_iterations_int
+ (get_chrec_loop (chrec_a), true);
+ niter_b = estimated_loop_iterations_int
+ (get_chrec_loop (chrec_b), true);
- if (numiter_a == NULL_TREE || numiter_b == NULL_TREE)
+ if (niter_a < 0 || niter_b < 0)
{
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;
+ *overlaps_a = conflict_fn_not_known ();
+ *overlaps_b = conflict_fn_not_known ();
*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;
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;
+ *overlaps_a = conflict_fn_no_dependence ();
+ *overlaps_b = conflict_fn_no_dependence ();
*last_conflicts = integer_zero_node;
}
loop, there is no dependence. */
if (x0 > niter || y0 > niter)
{
- *overlaps_a = chrec_known;
- *overlaps_b = chrec_known;
+ *overlaps_a = conflict_fn_no_dependence ();
+ *overlaps_b = conflict_fn_no_dependence ();
*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));
+ *overlaps_a
+ = conflict_fn (1,
+ affine_fn_univar (build_int_cst (NULL_TREE, x0),
+ 1,
+ build_int_cst (NULL_TREE, i1)));
+ *overlaps_b
+ = conflict_fn (1,
+ affine_fn_univar (build_int_cst (NULL_TREE, y0),
+ 1,
+ build_int_cst (NULL_TREE, j1)));
*last_conflicts = build_int_cst (NULL_TREE, last_conflict);
}
}
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;
+ *overlaps_a = conflict_fn_not_known ();
+ *overlaps_b = conflict_fn_not_known ();
*last_conflicts = chrec_dont_know;
}
}
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;
+ *overlaps_a = conflict_fn_not_known ();
+ *overlaps_b = conflict_fn_not_known ();
*last_conflicts = chrec_dont_know;
}
}
{
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;
+ *overlaps_a = conflict_fn_not_known ();
+ *overlaps_b = conflict_fn_not_known ();
*last_conflicts = chrec_dont_know;
}
}
{
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;
+ *overlaps_a = conflict_fn_not_known ();
+ *overlaps_b = conflict_fn_not_known ();
*last_conflicts = chrec_dont_know;
}
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, " (overlaps_a = ");
- print_generic_expr (dump_file, *overlaps_a, 0);
+ dump_conflict_function (dump_file, *overlaps_a);
fprintf (dump_file, ")\n (overlaps_b = ");
- print_generic_expr (dump_file, *overlaps_b, 0);
+ dump_conflict_function (dump_file, *overlaps_b);
fprintf (dump_file, ")\n");
fprintf (dump_file, ")\n");
}
static void
analyze_siv_subscript (tree chrec_a,
tree chrec_b,
- tree *overlaps_a,
- tree *overlaps_b,
+ conflict_function **overlaps_a,
+ conflict_function **overlaps_b,
tree *last_conflicts)
{
dependence_stats.num_siv++;
overlaps_a, overlaps_b,
last_conflicts);
- if (*overlaps_a == chrec_dont_know
- || *overlaps_b == chrec_dont_know)
+ if (CF_NOT_KNOWN_P (*overlaps_a)
+ || CF_NOT_KNOWN_P (*overlaps_b))
dependence_stats.num_siv_unimplemented++;
- else if (*overlaps_a == chrec_known
- || *overlaps_b == chrec_known)
+ else if (CF_NO_DEPENDENCE_P (*overlaps_a)
+ || CF_NO_DEPENDENCE_P (*overlaps_b))
dependence_stats.num_siv_independent++;
else
dependence_stats.num_siv_dependent++;
Compute it properly. */
*last_conflicts = chrec_dont_know;
- if (*overlaps_a == chrec_dont_know
- || *overlaps_b == chrec_dont_know)
+ if (CF_NOT_KNOWN_P (*overlaps_a)
+ || CF_NOT_KNOWN_P (*overlaps_b))
dependence_stats.num_siv_unimplemented++;
- else if (*overlaps_a == chrec_known
- || *overlaps_b == chrec_known)
+ else if (CF_NO_DEPENDENCE_P (*overlaps_a)
+ || CF_NO_DEPENDENCE_P (*overlaps_b))
dependence_stats.num_siv_independent++;
else
dependence_stats.num_siv_dependent++;
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;
+ *overlaps_a = conflict_fn_not_known ();
+ *overlaps_b = conflict_fn_not_known ();
*last_conflicts = chrec_dont_know;
dependence_stats.num_siv_unimplemented++;
}
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. */
+/* Returns false if we can prove that the greatest common divisor of the steps
+ of CHREC does not divide CST, false otherwise. */
static bool
-chrec_steps_divide_constant_p (tree chrec,
- tree cst,
- bool *res)
+gcd_of_steps_may_divide_p (tree chrec, tree cst)
{
- 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;
+ HOST_WIDE_INT cd = 0, val;
+ tree step;
- default:
- /* On the initial condition, return true. */
- return true;
+ if (!host_integerp (cst, 0))
+ return true;
+ val = tree_low_cst (cst, 0);
+
+ while (TREE_CODE (chrec) == POLYNOMIAL_CHREC)
+ {
+ step = CHREC_RIGHT (chrec);
+ if (!host_integerp (step, 0))
+ return true;
+ cd = gcd (cd, tree_low_cst (step, 0));
+ chrec = CHREC_LEFT (chrec);
}
+
+ return val % cd == 0;
}
/* Analyze a MIV (Multiple Index Variable) subscript. *OVERLAPS_A and
static void
analyze_miv_subscript (tree chrec_a,
tree chrec_b,
- tree *overlaps_a,
- tree *overlaps_b,
+ conflict_function **overlaps_a,
+ conflict_function **overlaps_b,
tree *last_conflicts)
{
/* FIXME: This is a MIV subscript, not yet handled.
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))
{
/* 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));
+ *overlaps_a = conflict_fn (1, affine_fn_cst (integer_zero_node));
+ *overlaps_b = conflict_fn (1, affine_fn_cst (integer_zero_node));
+ *last_conflicts = estimated_loop_iterations_tree
+ (get_chrec_loop (chrec_a), true);
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)
+ && !gcd_of_steps_may_divide_p (chrec_a, difference))
{
/* 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;
+ The difference is 1, and all the evolution steps are multiples
+ of 2, consequently there are no overlapping elements. */
+ *overlaps_a = conflict_fn_no_dependence ();
+ *overlaps_b = conflict_fn_no_dependence ();
*last_conflicts = integer_zero_node;
dependence_stats.num_miv_independent++;
}
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)
+ if (CF_NOT_KNOWN_P (*overlaps_a)
+ || CF_NOT_KNOWN_P (*overlaps_b))
dependence_stats.num_miv_unimplemented++;
- else if (*overlaps_a == chrec_known
- || *overlaps_b == chrec_known)
+ else if (CF_NO_DEPENDENCE_P (*overlaps_a)
+ || CF_NO_DEPENDENCE_P (*overlaps_b))
dependence_stats.num_miv_independent++;
else
dependence_stats.num_miv_dependent++;
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;
+ *overlaps_a = conflict_fn_not_known ();
+ *overlaps_b = conflict_fn_not_known ();
*last_conflicts = chrec_dont_know;
dependence_stats.num_miv_unimplemented++;
}
static void
analyze_overlapping_iterations (tree chrec_a,
tree chrec_b,
- tree *overlap_iterations_a,
- tree *overlap_iterations_b,
+ conflict_function **overlap_iterations_a,
+ conflict_function **overlap_iterations_b,
tree *last_conflicts)
{
dependence_stats.num_subscript_tests++;
{
dependence_stats.num_subscript_undetermined++;
- *overlap_iterations_a = chrec_dont_know;
- *overlap_iterations_b = chrec_dont_know;
+ *overlap_iterations_a = conflict_fn_not_known ();
+ *overlap_iterations_b = conflict_fn_not_known ();
}
/* If they are the same chrec, and are affine, they overlap
&& 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;
+ *overlap_iterations_a = conflict_fn (1, affine_fn_cst (integer_zero_node));
+ *overlap_iterations_b = conflict_fn (1, affine_fn_cst (integer_zero_node));
*last_conflicts = chrec_dont_know;
}
|| !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;
+ *overlap_iterations_a = conflict_fn_not_known ();
+ *overlap_iterations_b = conflict_fn_not_known ();
}
else if (ziv_subscript_p (chrec_a, chrec_b))
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, " (overlap_iterations_a = ");
- print_generic_expr (dump_file, *overlap_iterations_a, 0);
+ dump_conflict_function (dump_file, *overlap_iterations_a);
fprintf (dump_file, ")\n (overlap_iterations_b = ");
- print_generic_expr (dump_file, *overlap_iterations_b, 0);
+ dump_conflict_function (dump_file, *overlap_iterations_b);
fprintf (dump_file, ")\n");
fprintf (dump_file, ")\n");
}
return true;
}
+/* Return true when the DDR contains only constant access functions. */
+
+static bool
+constant_access_functions (struct data_dependence_relation *ddr)
+{
+ unsigned i;
+
+ for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++)
+ if (!evolution_function_is_constant_p (DR_ACCESS_FN (DDR_A (ddr), i))
+ || !evolution_function_is_constant_p (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. */
tree c_1 = CHREC_LEFT (c_2);
tree c_0 = CHREC_LEFT (c_1);
lambda_vector dist_v;
+ int v1, v2, cd;
/* Polynomials with more than 2 variables are not handled yet. */
if (TREE_CODE (c_0) != INTEGER_CST)
/* 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));
+ v1 = int_cst_value (CHREC_RIGHT (c_1));
+ v2 = int_cst_value (CHREC_RIGHT (c_2));
+ cd = gcd (v1, v2);
+ v1 /= cd;
+ v2 /= cd;
+
+ if (v2 < 0)
+ {
+ v2 = -v2;
+ v1 = -v1;
+ }
+
+ dist_v[x_1] = v2;
+ dist_v[x_2] = -v1;
save_dist_v (ddr, dist_v);
add_outer_distances (ddr, dist_v, x_1);
add_outer_distances (ddr, dist_v, index_carry);
}
+static void
+insert_innermost_unit_dist_vector (struct data_dependence_relation *ddr)
+{
+ lambda_vector dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr));
+
+ dist_v[DDR_INNER_LOOP (ddr)] = 1;
+ save_dist_v (ddr, dist_v);
+}
+
+/* Adds a unit distance vector to DDR when there is a 0 overlap. This
+ is the case for example when access functions are the same and
+ equal to a constant, as in:
+
+ | loop_1
+ | A[3] = ...
+ | ... = A[3]
+ | endloop_1
+
+ in which case the distance vectors are (0) and (1). */
+
+static void
+add_distance_for_zero_overlaps (struct data_dependence_relation *ddr)
+{
+ unsigned i, j;
+
+ for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++)
+ {
+ subscript_p sub = DDR_SUBSCRIPT (ddr, i);
+ conflict_function *ca = SUB_CONFLICTS_IN_A (sub);
+ conflict_function *cb = SUB_CONFLICTS_IN_B (sub);
+
+ for (j = 0; j < ca->n; j++)
+ if (affine_function_zero_p (ca->fns[j]))
+ {
+ insert_innermost_unit_dist_vector (ddr);
+ return;
+ }
+
+ for (j = 0; j < cb->n; j++)
+ if (affine_function_zero_p (cb->fns[j]))
+ {
+ insert_innermost_unit_dist_vector (ddr);
+ return;
+ }
+ }
+}
+
/* 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. */
dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr));
save_dist_v (ddr, dist_v);
+ if (constant_access_functions (ddr))
+ add_distance_for_zero_overlaps (ddr);
+
if (DDR_NB_LOOPS (ddr) > 1)
add_other_self_distances (ddr);
for (i = 0; VEC_iterate (subscript_p, DDR_SUBSCRIPTS (ddr), i, subscript);
i++)
{
- tree overlaps_a, overlaps_b;
+ conflict_function *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))
+ if (CF_NOT_KNOWN_P (overlaps_a)
+ || CF_NOT_KNOWN_P (overlaps_b))
{
finalize_ddr_dependent (ddr, chrec_dont_know);
dependence_stats.num_dependence_undetermined++;
+ free_conflict_function (overlaps_a);
+ free_conflict_function (overlaps_b);
return false;
}
- else if (overlaps_a == chrec_known
- || overlaps_b == chrec_known)
+ else if (CF_NO_DEPENDENCE_P (overlaps_a)
+ || CF_NO_DEPENDENCE_P (overlaps_b))
{
finalize_ddr_dependent (ddr, chrec_known);
dependence_stats.num_dependence_independent++;
+ free_conflict_function (overlaps_a);
+ free_conflict_function (overlaps_b);
return false;
}
access_functions_are_affine_or_constant_p (struct data_reference *a)
{
unsigned int i;
- VEC(tree,heap) **fns = DR_ACCESS_FNS_ADDR (a);
+ VEC(tree,heap) *fns = DR_ACCESS_FNS (a);
tree t;
-
- for (i = 0; VEC_iterate (tree, *fns, i, t); i++)
+
+ 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;
}
+/* Initializes an equation for an OMEGA problem using the information
+ contained in the ACCESS_FUN. Returns true when the operation
+ succeeded.
+
+ PB is the omega constraint system.
+ EQ is the number of the equation to be initialized.
+ OFFSET is used for shifting the variables names in the constraints:
+ a constrain is composed of 2 * the number of variables surrounding
+ dependence accesses. OFFSET is set either to 0 for the first n variables,
+ then it is set to n.
+ ACCESS_FUN is expected to be an affine chrec. */
+
+static bool
+init_omega_eq_with_af (omega_pb pb, unsigned eq,
+ unsigned int offset, tree access_fun,
+ struct data_dependence_relation *ddr)
+{
+ switch (TREE_CODE (access_fun))
+ {
+ case POLYNOMIAL_CHREC:
+ {
+ tree left = CHREC_LEFT (access_fun);
+ tree right = CHREC_RIGHT (access_fun);
+ int var = CHREC_VARIABLE (access_fun);
+ unsigned var_idx;
+
+ if (TREE_CODE (right) != INTEGER_CST)
+ return false;
+
+ var_idx = index_in_loop_nest (var, DDR_LOOP_NEST (ddr));
+ pb->eqs[eq].coef[offset + var_idx + 1] = int_cst_value (right);
+
+ /* Compute the innermost loop index. */
+ DDR_INNER_LOOP (ddr) = MAX (DDR_INNER_LOOP (ddr), var_idx);
+
+ if (offset == 0)
+ pb->eqs[eq].coef[var_idx + DDR_NB_LOOPS (ddr) + 1]
+ += int_cst_value (right);
+
+ switch (TREE_CODE (left))
+ {
+ case POLYNOMIAL_CHREC:
+ return init_omega_eq_with_af (pb, eq, offset, left, ddr);
+
+ case INTEGER_CST:
+ pb->eqs[eq].coef[0] += int_cst_value (left);
+ return true;
+
+ default:
+ return false;
+ }
+ }
+
+ case INTEGER_CST:
+ pb->eqs[eq].coef[0] += int_cst_value (access_fun);
+ return true;
+
+ default:
+ return false;
+ }
+}
+
+/* As explained in the comments preceding init_omega_for_ddr, we have
+ to set up a system for each loop level, setting outer loops
+ variation to zero, and current loop variation to positive or zero.
+ Save each lexico positive distance vector. */
+
+static void
+omega_extract_distance_vectors (omega_pb pb,
+ struct data_dependence_relation *ddr)
+{
+ int eq, geq;
+ unsigned i, j;
+ struct loop *loopi, *loopj;
+ enum omega_result res;
+
+ /* Set a new problem for each loop in the nest. The basis is the
+ problem that we have initialized until now. On top of this we
+ add new constraints. */
+ for (i = 0; i <= DDR_INNER_LOOP (ddr)
+ && VEC_iterate (loop_p, DDR_LOOP_NEST (ddr), i, loopi); i++)
+ {
+ int dist = 0;
+ omega_pb copy = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr),
+ DDR_NB_LOOPS (ddr));
+
+ omega_copy_problem (copy, pb);
+
+ /* For all the outer loops "loop_j", add "dj = 0". */
+ for (j = 0;
+ j < i && VEC_iterate (loop_p, DDR_LOOP_NEST (ddr), j, loopj); j++)
+ {
+ eq = omega_add_zero_eq (copy, omega_black);
+ copy->eqs[eq].coef[j + 1] = 1;
+ }
+
+ /* For "loop_i", add "0 <= di". */
+ geq = omega_add_zero_geq (copy, omega_black);
+ copy->geqs[geq].coef[i + 1] = 1;
+
+ /* Reduce the constraint system, and test that the current
+ problem is feasible. */
+ res = omega_simplify_problem (copy);
+ if (res == omega_false
+ || res == omega_unknown
+ || copy->num_geqs > (int) DDR_NB_LOOPS (ddr))
+ goto next_problem;
+
+ for (eq = 0; eq < copy->num_subs; eq++)
+ if (copy->subs[eq].key == (int) i + 1)
+ {
+ dist = copy->subs[eq].coef[0];
+ goto found_dist;
+ }
+
+ if (dist == 0)
+ {
+ /* Reinitialize problem... */
+ omega_copy_problem (copy, pb);
+ for (j = 0;
+ j < i && VEC_iterate (loop_p, DDR_LOOP_NEST (ddr), j, loopj); j++)
+ {
+ eq = omega_add_zero_eq (copy, omega_black);
+ copy->eqs[eq].coef[j + 1] = 1;
+ }
+
+ /* ..., but this time "di = 1". */
+ eq = omega_add_zero_eq (copy, omega_black);
+ copy->eqs[eq].coef[i + 1] = 1;
+ copy->eqs[eq].coef[0] = -1;
+
+ res = omega_simplify_problem (copy);
+ if (res == omega_false
+ || res == omega_unknown
+ || copy->num_geqs > (int) DDR_NB_LOOPS (ddr))
+ goto next_problem;
+
+ for (eq = 0; eq < copy->num_subs; eq++)
+ if (copy->subs[eq].key == (int) i + 1)
+ {
+ dist = copy->subs[eq].coef[0];
+ goto found_dist;
+ }
+ }
+
+ found_dist:;
+ /* Save the lexicographically positive distance vector. */
+ if (dist >= 0)
+ {
+ lambda_vector dist_v = lambda_vector_new (DDR_NB_LOOPS (ddr));
+ lambda_vector dir_v = lambda_vector_new (DDR_NB_LOOPS (ddr));
+
+ dist_v[i] = dist;
+
+ for (eq = 0; eq < copy->num_subs; eq++)
+ if (copy->subs[eq].key > 0)
+ {
+ dist = copy->subs[eq].coef[0];
+ dist_v[copy->subs[eq].key - 1] = dist;
+ }
+
+ for (j = 0; j < DDR_NB_LOOPS (ddr); j++)
+ dir_v[j] = dir_from_dist (dist_v[j]);
+
+ save_dist_v (ddr, dist_v);
+ save_dir_v (ddr, dir_v);
+ }
+
+ next_problem:;
+ omega_free_problem (copy);
+ }
+}
+
+/* This is called for each subscript of a tuple of data references:
+ insert an equality for representing the conflicts. */
+
+static bool
+omega_setup_subscript (tree access_fun_a, tree access_fun_b,
+ struct data_dependence_relation *ddr,
+ omega_pb pb, bool *maybe_dependent)
+{
+ int eq;
+ tree fun_a = chrec_convert (integer_type_node, access_fun_a, NULL_TREE);
+ tree fun_b = chrec_convert (integer_type_node, access_fun_b, NULL_TREE);
+ tree difference = chrec_fold_minus (integer_type_node, fun_a, fun_b);
+
+ /* When the fun_a - fun_b is not constant, the dependence is not
+ captured by the classic distance vector representation. */
+ if (TREE_CODE (difference) != INTEGER_CST)
+ return false;
+
+ /* ZIV test. */
+ if (ziv_subscript_p (fun_a, fun_b) && !integer_zerop (difference))
+ {
+ /* There is no dependence. */
+ *maybe_dependent = false;
+ return true;
+ }
+
+ fun_b = chrec_fold_multiply (integer_type_node, fun_b,
+ integer_minus_one_node);
+
+ eq = omega_add_zero_eq (pb, omega_black);
+ if (!init_omega_eq_with_af (pb, eq, DDR_NB_LOOPS (ddr), fun_a, ddr)
+ || !init_omega_eq_with_af (pb, eq, 0, fun_b, ddr))
+ /* There is probably a dependence, but the system of
+ constraints cannot be built: answer "don't know". */
+ return false;
+
+ /* GCD test. */
+ if (DDR_NB_LOOPS (ddr) != 0 && pb->eqs[eq].coef[0]
+ && !int_divides_p (lambda_vector_gcd
+ ((lambda_vector) &(pb->eqs[eq].coef[1]),
+ 2 * DDR_NB_LOOPS (ddr)),
+ pb->eqs[eq].coef[0]))
+ {
+ /* There is no dependence. */
+ *maybe_dependent = false;
+ return true;
+ }
+
+ return true;
+}
+
+/* Helper function, same as init_omega_for_ddr but specialized for
+ data references A and B. */
+
+static bool
+init_omega_for_ddr_1 (struct data_reference *dra, struct data_reference *drb,
+ struct data_dependence_relation *ddr,
+ omega_pb pb, bool *maybe_dependent)
+{
+ unsigned i;
+ int ineq;
+ struct loop *loopi;
+ unsigned nb_loops = DDR_NB_LOOPS (ddr);
+
+ /* Insert an equality per subscript. */
+ for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++)
+ {
+ if (!omega_setup_subscript (DR_ACCESS_FN (dra, i), DR_ACCESS_FN (drb, i),
+ ddr, pb, maybe_dependent))
+ return false;
+ else if (*maybe_dependent == false)
+ {
+ /* There is no dependence. */
+ DDR_ARE_DEPENDENT (ddr) = chrec_known;
+ return true;
+ }
+ }
+
+ /* Insert inequalities: constraints corresponding to the iteration
+ domain, i.e. the loops surrounding the references "loop_x" and
+ the distance variables "dx". The layout of the OMEGA
+ representation is as follows:
+ - coef[0] is the constant
+ - coef[1..nb_loops] are the protected variables that will not be
+ removed by the solver: the "dx"
+ - coef[nb_loops + 1, 2*nb_loops] are the loop variables: "loop_x".
+ */
+ for (i = 0; i <= DDR_INNER_LOOP (ddr)
+ && VEC_iterate (loop_p, DDR_LOOP_NEST (ddr), i, loopi); i++)
+ {
+ HOST_WIDE_INT nbi = estimated_loop_iterations_int (loopi, true);
+
+ /* 0 <= loop_x */
+ ineq = omega_add_zero_geq (pb, omega_black);
+ pb->geqs[ineq].coef[i + nb_loops + 1] = 1;
+
+ /* 0 <= loop_x + dx */
+ ineq = omega_add_zero_geq (pb, omega_black);
+ pb->geqs[ineq].coef[i + nb_loops + 1] = 1;
+ pb->geqs[ineq].coef[i + 1] = 1;
+
+ if (nbi != -1)
+ {
+ /* loop_x <= nb_iters */
+ ineq = omega_add_zero_geq (pb, omega_black);
+ pb->geqs[ineq].coef[i + nb_loops + 1] = -1;
+ pb->geqs[ineq].coef[0] = nbi;
+
+ /* loop_x + dx <= nb_iters */
+ ineq = omega_add_zero_geq (pb, omega_black);
+ pb->geqs[ineq].coef[i + nb_loops + 1] = -1;
+ pb->geqs[ineq].coef[i + 1] = -1;
+ pb->geqs[ineq].coef[0] = nbi;
+
+ /* A step "dx" bigger than nb_iters is not feasible, so
+ add "0 <= nb_iters + dx", */
+ ineq = omega_add_zero_geq (pb, omega_black);
+ pb->geqs[ineq].coef[i + 1] = 1;
+ pb->geqs[ineq].coef[0] = nbi;
+ /* and "dx <= nb_iters". */
+ ineq = omega_add_zero_geq (pb, omega_black);
+ pb->geqs[ineq].coef[i + 1] = -1;
+ pb->geqs[ineq].coef[0] = nbi;
+ }
+ }
+
+ omega_extract_distance_vectors (pb, ddr);
+
+ return true;
+}
+
+/* Sets up the Omega dependence problem for the data dependence
+ relation DDR. Returns false when the constraint system cannot be
+ built, ie. when the test answers "don't know". Returns true
+ otherwise, and when independence has been proved (using one of the
+ trivial dependence test), set MAYBE_DEPENDENT to false, otherwise
+ set MAYBE_DEPENDENT to true.
+
+ Example: for setting up the dependence system corresponding to the
+ conflicting accesses
+
+ | loop_i
+ | loop_j
+ | A[i, i+1] = ...
+ | ... A[2*j, 2*(i + j)]
+ | endloop_j
+ | endloop_i
+
+ the following constraints come from the iteration domain:
+
+ 0 <= i <= Ni
+ 0 <= i + di <= Ni
+ 0 <= j <= Nj
+ 0 <= j + dj <= Nj
+
+ where di, dj are the distance variables. The constraints
+ representing the conflicting elements are:
+
+ i = 2 * (j + dj)
+ i + 1 = 2 * (i + di + j + dj)
+
+ For asking that the resulting distance vector (di, dj) be
+ lexicographically positive, we insert the constraint "di >= 0". If
+ "di = 0" in the solution, we fix that component to zero, and we
+ look at the inner loops: we set a new problem where all the outer
+ loop distances are zero, and fix this inner component to be
+ positive. When one of the components is positive, we save that
+ distance, and set a new problem where the distance on this loop is
+ zero, searching for other distances in the inner loops. Here is
+ the classic example that illustrates that we have to set for each
+ inner loop a new problem:
+
+ | loop_1
+ | loop_2
+ | A[10]
+ | endloop_2
+ | endloop_1
+
+ we have to save two distances (1, 0) and (0, 1).
+
+ Given two array references, refA and refB, we have to set the
+ dependence problem twice, refA vs. refB and refB vs. refA, and we
+ cannot do a single test, as refB might occur before refA in the
+ inner loops, and the contrary when considering outer loops: ex.
+
+ | loop_0
+ | loop_1
+ | loop_2
+ | T[{1,+,1}_2][{1,+,1}_1] // refA
+ | T[{2,+,1}_2][{0,+,1}_1] // refB
+ | endloop_2
+ | endloop_1
+ | endloop_0
+
+ refB touches the elements in T before refA, and thus for the same
+ loop_0 refB precedes refA: ie. the distance vector (0, 1, -1)
+ but for successive loop_0 iterations, we have (1, -1, 1)
+
+ The Omega solver expects the distance variables ("di" in the
+ previous example) to come first in the constraint system (as
+ variables to be protected, or "safe" variables), the constraint
+ system is built using the following layout:
+
+ "cst | distance vars | index vars".
+*/
+
+static bool
+init_omega_for_ddr (struct data_dependence_relation *ddr,
+ bool *maybe_dependent)
+{
+ omega_pb pb;
+ bool res = false;
+
+ *maybe_dependent = true;
+
+ if (same_access_functions (ddr))
+ {
+ unsigned j;
+ lambda_vector dir_v;
+
+ /* Save the 0 vector. */
+ save_dist_v (ddr, lambda_vector_new (DDR_NB_LOOPS (ddr)));
+ dir_v = lambda_vector_new (DDR_NB_LOOPS (ddr));
+ for (j = 0; j < DDR_NB_LOOPS (ddr); j++)
+ dir_v[j] = dir_equal;
+ save_dir_v (ddr, dir_v);
+
+ /* Save the dependences carried by outer loops. */
+ pb = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), DDR_NB_LOOPS (ddr));
+ res = init_omega_for_ddr_1 (DDR_A (ddr), DDR_B (ddr), ddr, pb,
+ maybe_dependent);
+ omega_free_problem (pb);
+ return res;
+ }
+
+ /* Omega expects the protected variables (those that have to be kept
+ after elimination) to appear first in the constraint system.
+ These variables are the distance variables. In the following
+ initialization we declare NB_LOOPS safe variables, and the total
+ number of variables for the constraint system is 2*NB_LOOPS. */
+ pb = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), DDR_NB_LOOPS (ddr));
+ res = init_omega_for_ddr_1 (DDR_A (ddr), DDR_B (ddr), ddr, pb,
+ maybe_dependent);
+ omega_free_problem (pb);
+
+ /* Stop computation if not decidable, or no dependence. */
+ if (res == false || *maybe_dependent == false)
+ return res;
+
+ pb = omega_alloc_problem (2 * DDR_NB_LOOPS (ddr), DDR_NB_LOOPS (ddr));
+ res = init_omega_for_ddr_1 (DDR_B (ddr), DDR_A (ddr), ddr, pb,
+ maybe_dependent);
+ omega_free_problem (pb);
+
+ return res;
+}
+
+/* Return true when DDR contains the same information as that stored
+ in DIR_VECTS and in DIST_VECTS, return false otherwise. */
+
+static bool
+ddr_consistent_p (FILE *file,
+ struct data_dependence_relation *ddr,
+ VEC (lambda_vector, heap) *dist_vects,
+ VEC (lambda_vector, heap) *dir_vects)
+{
+ unsigned int i, j;
+
+ /* If dump_file is set, output there. */
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ file = dump_file;
+
+ if (VEC_length (lambda_vector, dist_vects) != DDR_NUM_DIST_VECTS (ddr))
+ {
+ lambda_vector b_dist_v;
+ fprintf (file, "\n(Number of distance vectors differ: Banerjee has %d, Omega has %d.\n",
+ VEC_length (lambda_vector, dist_vects),
+ DDR_NUM_DIST_VECTS (ddr));
+
+ fprintf (file, "Banerjee dist vectors:\n");
+ for (i = 0; VEC_iterate (lambda_vector, dist_vects, i, b_dist_v); i++)
+ print_lambda_vector (file, b_dist_v, DDR_NB_LOOPS (ddr));
+
+ fprintf (file, "Omega dist vectors:\n");
+ for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++)
+ print_lambda_vector (file, DDR_DIST_VECT (ddr, i), DDR_NB_LOOPS (ddr));
+
+ fprintf (file, "data dependence relation:\n");
+ dump_data_dependence_relation (file, ddr);
+
+ fprintf (file, ")\n");
+ return false;
+ }
+
+ if (VEC_length (lambda_vector, dir_vects) != DDR_NUM_DIR_VECTS (ddr))
+ {
+ fprintf (file, "\n(Number of direction vectors differ: Banerjee has %d, Omega has %d.)\n",
+ VEC_length (lambda_vector, dir_vects),
+ DDR_NUM_DIR_VECTS (ddr));
+ return false;
+ }
+
+ for (i = 0; i < DDR_NUM_DIST_VECTS (ddr); i++)
+ {
+ lambda_vector a_dist_v;
+ lambda_vector b_dist_v = DDR_DIST_VECT (ddr, i);
+
+ /* Distance vectors are not ordered in the same way in the DDR
+ and in the DIST_VECTS: search for a matching vector. */
+ for (j = 0; VEC_iterate (lambda_vector, dist_vects, j, a_dist_v); j++)
+ if (lambda_vector_equal (a_dist_v, b_dist_v, DDR_NB_LOOPS (ddr)))
+ break;
+
+ if (j == VEC_length (lambda_vector, dist_vects))
+ {
+ fprintf (file, "\n(Dist vectors from the first dependence analyzer:\n");
+ print_dist_vectors (file, dist_vects, DDR_NB_LOOPS (ddr));
+ fprintf (file, "not found in Omega dist vectors:\n");
+ print_dist_vectors (file, DDR_DIST_VECTS (ddr), DDR_NB_LOOPS (ddr));
+ fprintf (file, "data dependence relation:\n");
+ dump_data_dependence_relation (file, ddr);
+ fprintf (file, ")\n");
+ }
+ }
+
+ for (i = 0; i < DDR_NUM_DIR_VECTS (ddr); i++)
+ {
+ lambda_vector a_dir_v;
+ lambda_vector b_dir_v = DDR_DIR_VECT (ddr, i);
+
+ /* Direction vectors are not ordered in the same way in the DDR
+ and in the DIR_VECTS: search for a matching vector. */
+ for (j = 0; VEC_iterate (lambda_vector, dir_vects, j, a_dir_v); j++)
+ if (lambda_vector_equal (a_dir_v, b_dir_v, DDR_NB_LOOPS (ddr)))
+ break;
+
+ if (j == VEC_length (lambda_vector, dist_vects))
+ {
+ fprintf (file, "\n(Dir vectors from the first dependence analyzer:\n");
+ print_dir_vectors (file, dir_vects, DDR_NB_LOOPS (ddr));
+ fprintf (file, "not found in Omega dir vectors:\n");
+ print_dir_vectors (file, DDR_DIR_VECTS (ddr), DDR_NB_LOOPS (ddr));
+ fprintf (file, "data dependence relation:\n");
+ dump_data_dependence_relation (file, ddr);
+ fprintf (file, ")\n");
+ }
+ }
+
+ 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
if (access_functions_are_affine_or_constant_p (dra)
&& access_functions_are_affine_or_constant_p (drb))
- subscript_dependence_tester (ddr);
-
+ {
+ if (flag_check_data_deps)
+ {
+ /* Compute the dependences using the first algorithm. */
+ subscript_dependence_tester (ddr);
+
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ {
+ fprintf (dump_file, "\n\nBanerjee Analyzer\n");
+ dump_data_dependence_relation (dump_file, ddr);
+ }
+
+ if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE)
+ {
+ bool maybe_dependent;
+ VEC (lambda_vector, heap) *dir_vects, *dist_vects;
+
+ /* Save the result of the first DD analyzer. */
+ dist_vects = DDR_DIST_VECTS (ddr);
+ dir_vects = DDR_DIR_VECTS (ddr);
+
+ /* Reset the information. */
+ DDR_DIST_VECTS (ddr) = NULL;
+ DDR_DIR_VECTS (ddr) = NULL;
+
+ /* Compute the same information using Omega. */
+ if (!init_omega_for_ddr (ddr, &maybe_dependent))
+ goto csys_dont_know;
+
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ {
+ fprintf (dump_file, "Omega Analyzer\n");
+ dump_data_dependence_relation (dump_file, ddr);
+ }
+
+ /* Check that we get the same information. */
+ if (maybe_dependent)
+ gcc_assert (ddr_consistent_p (stderr, ddr, dist_vects,
+ dir_vects));
+ }
+ }
+ else
+ 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
{
+ csys_dont_know:;
dependence_stats.num_dependence_undetermined++;
if (dump_file && (dump_flags & TDF_DETAILS))
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_CONFLICTS_IN_A (subscript)
+ = conflict_fn (1, affine_fn_cst (integer_zero_node));
+ SUB_CONFLICTS_IN_B (subscript)
+ = conflict_fn (1, affine_fn_cst (integer_zero_node));
SUB_LAST_CONFLICT (subscript) = chrec_dont_know;
}
{
bool clobbers_memory = false;
data_ref_loc *ref;
- tree *op0, *op1, args, call;
+ tree *op0, *op1, call;
*references = NULL;
if (call)
{
- for (args = TREE_OPERAND (call, 1); args; args = TREE_CHAIN (args))
+ unsigned i, n = call_expr_nargs (call);
+
+ for (i = 0; i < n; i++)
{
- op0 = &TREE_VALUE (args);
+ op0 = &CALL_EXPR_ARG (call, i);
+
if (DECL_P (*op0)
|| REFERENCE_CLASS_P (*op0))
{
}
/* Entry point (for testing only). Analyze all the data references
- and the dependence relations.
+ and the dependence relations in LOOP.
The data references are computed first.
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)
+analyze_all_data_dependences (struct loop *loop)
{
unsigned int i;
int nb_data_refs = 10;
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);
+ compute_data_dependences_for_loop (loop, false, &datarefs,
+ &dependence_relations);
if (dump_file)
{
free_dependence_relations (dependence_relations);
free_data_refs (datarefs);
}
-#endif
+
+/* Computes all the data dependences and check that the results of
+ several analyzers are the same. */
+
+void
+tree_check_data_deps (void)
+{
+ loop_iterator li;
+ struct loop *loop_nest;
+
+ FOR_EACH_LOOP (li, loop_nest, 0)
+ analyze_all_data_dependences (loop_nest);
+}
/* Free the memory used by a data dependence relation DDR. */
return;
if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE && DDR_SUBSCRIPTS (ddr))
- VEC_free (subscript_p, heap, DDR_SUBSCRIPTS (ddr));
+ free_subscripts (DDR_SUBSCRIPTS (ddr));
free (ddr);
}
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