Hi,
this tidies ssa liveness calculation a bit (related to out-of-ssa). In
particular it doesn't make use of var annotations to compress the index
space from partitions to base variable indices anymore, but instead a
hashmap built on the fly when we need it. The basevars itself actually
aren't needed at all (currently only for checking), only a mapping for
which ssa names belong to the same base variable.
Regstrapped with the other two patches on x86_64-linux. Okay for trunk?
Ciao,
Michael.
* tree-flow.h (struct var_ann_d): Remove base_var_processed and
base_index members.
* tree-ssa-live.h (struct _var_map): Remove basevars member.
(VAR_ANN_BASE_INDEX): Remove.
* tree-ssa-live.c (var_map_base_init): Use a hash table instead
of var annotation to compress index space. Don't deal with above
removed members.
(var_map_base_fini): Don't free basevars.
(init_var_map): Don't clear basevars.
Index: tree-flow.h
===================================================================
*** tree-flow.h.orig 2012-08-01 15:59:27.000000000 +0200
--- tree-flow.h 2012-08-01 15:59:35.000000000 +0200
*************** enum need_phi_state {
*** 178,192 ****
struct GTY(()) var_ann_d {
- /* Used when building base variable structures in a var_map. */
- unsigned base_var_processed : 1;
-
/* Nonzero if this variable was used after SSA optimizations were
applied. We set this when translating out of SSA form. */
unsigned used : 1;
-
- /* Used by var_map for the base index of ssa base variables. */
- unsigned base_index;
};
--- 178,186 ----
Index: tree-ssa-live.h
===================================================================
*** tree-ssa-live.h.orig 2012-08-01 15:58:34.000000000 +0200
--- tree-ssa-live.h 2012-08-01 15:59:35.000000000 +0200
*************** along with GCC; see the file COPYING3.
*** 31,43 ****
/* Used to create the variable mapping when we go out of SSA form.
Mapping from an ssa_name to a partition number is maintained, as well as
! partition number to back to ssa_name. A partition can also be represented
! by a non-ssa_name variable. This allows ssa_names and their partition to
! be coalesced with live on entry compiler variables, as well as eventually
! having real compiler variables assigned to each partition as part of the
! final stage of going of of ssa.
!
! Non-ssa_names maintain their partition index in the variable annotation.
This data structure also supports "views", which work on a subset of all
partitions. This allows the coalescer to decide what partitions are
--- 31,37 ----
/* Used to create the variable mapping when we go out of SSA form.
Mapping from an ssa_name to a partition number is maintained, as well as
! partition number back to ssa_name.
This data structure also supports "views", which work on a subset of all
partitions. This allows the coalescer to decide what partitions are
*************** typedef struct _var_map
*** 72,87 ****
/* Map of partitions numbers to base variable table indexes. */
int *partition_to_base_index;
-
- /* Table of base variable's. */
- VEC (tree, heap) *basevars;
} *var_map;
- /* Index to the basevar table of a non ssa-name variable. */
- #define VAR_ANN_BASE_INDEX(ann) (ann->base_index)
-
-
/* Value used to represent no partition number. */
#define NO_PARTITION -1
--- 66,74 ----
Index: tree-ssa-live.c
===================================================================
*** tree-ssa-live.c.orig 2012-08-01 15:58:34.000000000 +0200
--- tree-ssa-live.c 2012-08-01 15:59:35.000000000 +0200
*************** static void verify_live_on_entry (tree_
*** 59,117 ****
static void
var_map_base_init (var_map map)
{
! int x, num_part, num;
tree var;
! var_ann_t ann;
- num = 0;
num_part = num_var_partitions (map);
/* If a base table already exists, clear it, otherwise create it. */
! if (map->partition_to_base_index != NULL)
! {
! free (map->partition_to_base_index);
! VEC_truncate (tree, map->basevars, 0);
! }
! else
! map->basevars = VEC_alloc (tree, heap, MAX (40, (num_part / 10)));
!
map->partition_to_base_index = (int *) xmalloc (sizeof (int) * num_part);
/* Build the base variable list, and point partitions at their bases. */
for (x = 0; x < num_part; x++)
{
var = partition_to_var (map, x);
! if (TREE_CODE (var) == SSA_NAME)
! var = SSA_NAME_VAR (var);
! ann = var_ann (var);
/* If base variable hasn't been seen, set it up. */
! if (!ann->base_var_processed)
! {
! ann->base_var_processed = 1;
! VAR_ANN_BASE_INDEX (ann) = num++;
! VEC_safe_push (tree, heap, map->basevars, var);
}
! map->partition_to_base_index[x] = VAR_ANN_BASE_INDEX (ann);
}
! map->num_basevars = num;
! /* Now clear the processed bit. */
! for (x = 0; x < num; x++)
! {
! var = VEC_index (tree, map->basevars, x);
! var_ann (var)->base_var_processed = 0;
! }
!
! #ifdef ENABLE_CHECKING
! for (x = 0; x < num_part; x++)
! {
! tree var2;
! var = SSA_NAME_VAR (partition_to_var (map, x));
! var2 = VEC_index (tree, map->basevars, basevar_index (map, x));
! gcc_assert (var == var2);
! }
! #endif
}
--- 59,107 ----
static void
var_map_base_init (var_map map)
{
! int x, num_part;
tree var;
! htab_t decl_to_index;
! struct tree_int_map *m, *mapstorage;
num_part = num_var_partitions (map);
+ decl_to_index = htab_create (num_part, tree_decl_map_hash,
+ tree_int_map_eq, NULL);
+ /* We can have at most num_part entries in the hash tables, so it's
+ enough to allocate so many map elements once, saving some malloc
+ calls. */
+ mapstorage = m = XNEWVEC (struct tree_int_map, num_part);
/* If a base table already exists, clear it, otherwise create it. */
! free (map->partition_to_base_index);
map->partition_to_base_index = (int *) xmalloc (sizeof (int) * num_part);
/* Build the base variable list, and point partitions at their bases. */
for (x = 0; x < num_part; x++)
{
+ struct tree_int_map **slot;
+ unsigned baseindex;
var = partition_to_var (map, x);
! var = SSA_NAME_VAR (var);
/* If base variable hasn't been seen, set it up. */
! m->base.from = var;
! slot = (struct tree_int_map **) htab_find_slot (decl_to_index, m,
INSERT);
! if (!*slot)
! {
! baseindex = m - mapstorage;
! m->to = baseindex;
! *slot = m;
! m++;
}
! else
! baseindex = (*slot)->to;
! map->partition_to_base_index[x] = baseindex;
}
! map->num_basevars = m - mapstorage;
! free (mapstorage);
! htab_delete (decl_to_index);
}
*************** var_map_base_fini (var_map map)
*** 123,129 ****
/* Free the basevar info if it is present. */
if (map->partition_to_base_index != NULL)
{
- VEC_free (tree, heap, map->basevars);
free (map->partition_to_base_index);
map->partition_to_base_index = NULL;
map->num_basevars = 0;
--- 113,118 ----
*************** init_var_map (int size)
*** 145,151 ****
map->partition_size = size;
map->num_basevars = 0;
map->partition_to_base_index = NULL;
- map->basevars = NULL;
return map;
}
--- 134,139 ----
