/* Linear Loop transforms
- Copyright (C) 2003, 2004, 2005, 2007 Free Software Foundation, Inc.
+ Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009
+ Free Software Foundation, Inc.
Contributed by Daniel Berlin <dberlin@dberlin.org>.
This file is part of GCC.
scaling, skewing, and reversal. They are used to change the
iteration order of loop nests in order to optimize data locality of
traversals, or remove dependences that prevent
- parallelization/vectorization/etc.
+ parallelization/vectorization/etc.
TODO: Determine reuse vectors/matrix and use it to determine optimal
transform matrix for locality purposes.
considered. The first loop in the considered loop nest is
FIRST_LOOP, and consequently, the index of the considered loop is
obtained by LOOP->DEPTH - FIRST_LOOP->DEPTH
-
+
Initializes:
- DEPENDENCE_STEPS the sum of all the data dependence distances
carried by loop LOOP,
| A[{0, +, 1336}_1]
| endloop_1
- gather_interchange_stats (in loop_1) will return
+ gather_interchange_stats (in loop_1) will return
DEPENDENCE_STEPS = 3002
NB_DEPS_NOT_CARRIED_BY_LOOP = 5
ACCESS_STRIDES = 10694
- gather_interchange_stats (in loop_2) will return
+ gather_interchange_stats (in loop_2) will return
DEPENDENCE_STEPS = 3000
NB_DEPS_NOT_CARRIED_BY_LOOP = 7
ACCESS_STRIDES = 8010
VEC (data_reference_p, heap) *datarefs ATTRIBUTE_UNUSED,
struct loop *loop ATTRIBUTE_UNUSED,
struct loop *first_loop ATTRIBUTE_UNUSED,
- unsigned int *dependence_steps ATTRIBUTE_UNUSED,
- unsigned int *nb_deps_not_carried_by_loop ATTRIBUTE_UNUSED,
+ unsigned int *dependence_steps ATTRIBUTE_UNUSED,
+ unsigned int *nb_deps_not_carried_by_loop ATTRIBUTE_UNUSED,
double_int *access_strides ATTRIBUTE_UNUSED)
{
unsigned int i, j;
struct loop *stmt_loop = loop_containing_stmt (stmt);
struct loop *inner_loop = first_loop->inner;
- if (inner_loop != stmt_loop
+ if (inner_loop != stmt_loop
&& !flow_loop_nested_p (inner_loop, stmt_loop))
continue;
- for (it = 0; it < DR_NUM_DIMENSIONS (dr);
+ for (it = 0; it < DR_NUM_DIMENSIONS (dr);
it++, ref = TREE_OPERAND (ref, 0))
{
int num = am_vector_index_for_loop (DR_ACCESS_MATRIX (dr), loop->num);
tree array_size = TYPE_SIZE (TREE_TYPE (ref));
double_int dstride;
- if (array_size == NULL_TREE
+ if (array_size == NULL_TREE
|| TREE_CODE (array_size) != INTEGER_CST)
continue;
- dstride = double_int_mul (tree_to_double_int (array_size),
+ dstride = double_int_mul (tree_to_double_int (array_size),
shwi_to_double_int (istride));
(*access_strides) = double_int_add (*access_strides, dstride);
}
}
/* Attempt to apply interchange transformations to TRANS to maximize the
- spatial and temporal locality of the loop.
+ spatial and temporal locality of the loop.
Returns the new transform matrix. The smaller the reuse vector
distances in the inner loops, the fewer the cache misses.
FIRST_LOOP is the loop->num of the first loop in the analyzed loop
static lambda_trans_matrix
-try_interchange_loops (lambda_trans_matrix trans,
- unsigned int depth,
+try_interchange_loops (lambda_trans_matrix trans,
+ unsigned int depth,
VEC (ddr_p, heap) *dependence_relations,
VEC (data_reference_p, heap) *datarefs,
struct loop *first_loop)
l2_cache_size = uhwi_to_double_int (L2_CACHE_SIZE * 1024);
/* LOOP_I is always the outer loop. */
- for (loop_j = first_loop->inner;
- loop_j;
+ for (loop_j = first_loop->inner;
+ loop_j;
loop_j = loop_j->inner)
- for (loop_i = first_loop;
- loop_depth (loop_i) < loop_depth (loop_j);
+ for (loop_i = first_loop;
+ loop_depth (loop_i) < loop_depth (loop_j);
loop_i = loop_i->inner)
{
gather_interchange_stats (dependence_relations, datarefs,
loop_i, first_loop,
- &dependence_steps_i,
+ &dependence_steps_i,
&nb_deps_not_carried_by_i,
&access_strides_i);
gather_interchange_stats (dependence_relations, datarefs,
loop_j, first_loop,
- &dependence_steps_j,
- &nb_deps_not_carried_by_j,
+ &dependence_steps_j,
+ &nb_deps_not_carried_by_j,
&access_strides_j);
-
+
/* Heuristics for loop interchange profitability:
0. Don't transform if the smallest stride is larger than
if (res && double_int_ucmp (large, l1_cache_size) < 0)
continue;
- if (dependence_steps_i < dependence_steps_j
+ if (dependence_steps_i < dependence_steps_j
|| nb_deps_not_carried_by_i > nb_deps_not_carried_by_j
|| cmp < 0)
{
/* Validate the resulting matrix. When the transformation
is not valid, reverse to the previous transformation. */
if (!lambda_transform_legal_p (trans, depth, dependence_relations))
- lambda_matrix_row_exchange (LTM_MATRIX (trans),
- loop_depth (loop_i) - loop_depth (first_loop),
+ lambda_matrix_row_exchange (LTM_MATRIX (trans),
+ loop_depth (loop_i) - loop_depth (first_loop),
loop_depth (loop_j) - loop_depth (first_loop));
}
}
unsigned int depth = 0;
VEC (ddr_p, heap) *dependence_relations;
VEC (data_reference_p, heap) *datarefs;
-
+
lambda_loopnest before, after;
lambda_trans_matrix trans;
struct obstack lambda_obstack;
struct loop *loop;
- VEC(loop_p,heap) *nest = VEC_alloc (loop_p, heap, 3);
+ VEC(loop_p,heap) *nest;
depth = perfect_loop_nest_depth (loop_nest);
if (depth == 0)
continue;
+ nest = VEC_alloc (loop_p, heap, 3);
for (loop = loop_nest; loop; loop = loop->inner)
VEC_safe_push (loop_p, heap, nest, loop);
if (!compute_data_dependences_for_loop (loop_nest, true, &datarefs,
&dependence_relations))
goto free_and_continue;
-
+
lambda_collect_parameters (datarefs, &lambda_parameters);
if (!lambda_compute_access_matrices (datarefs, lambda_parameters, nest))
goto free_and_continue;
fprintf (dump_file, "Before:\n");
print_lambda_loopnest (dump_file, before, 'i');
}
-
+
after = lambda_loopnest_transform (before, trans, &lambda_obstack);
if (dump_file)
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