(ALIGN/MISALIGNED_)INDIRECT_REF nodes for the pointer passed in DATA. */
static tree
-count_ptr_derefs (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED, void *data)
+count_ptr_derefs (tree *tp, int *walk_subtrees, void *data)
{
struct count_ptr_d *count_p = (struct count_ptr_d *) data;
+ /* Do not walk inside ADDR_EXPR nodes. In the expression &ptr->fld,
+ pointer 'ptr' is *not* dereferenced, it is simply used to compute
+ the address of 'fld' as 'ptr + offsetof(fld)'. */
+ if (TREE_CODE (*tp) == ADDR_EXPR)
+ {
+ *walk_subtrees = 0;
+ return NULL_TREE;
+ }
+
if (INDIRECT_REF_P (*tp) && TREE_OPERAND (*tp, 0) == count_p->ptr)
-/* || (TREE_CODE (*tp) == MEM_REF && MEM_REF_SYMBOL (*tp) == count_p->ptr)) */
count_p->count++;
return NULL_TREE;
delete_points_to_sets ();
}
-
/* Create name tags for all the pointers that have been dereferenced.
We only create a name tag for a pointer P if P is found to point to
a set of variables (so that we can alias them to *P) or if it is
create_name_tags (void)
{
size_t i;
+ VEC (tree, heap) *with_ptvars = NULL;
+ tree ptr;
+ /* Collect the list of pointers with a non-empty points to set. */
for (i = 1; i < num_ssa_names; i++)
{
tree ptr = ssa_name (i);
continue;
}
- if (pi->pt_vars && !bitmap_empty_p (pi->pt_vars))
+ /* Set pt_anything on the pointers without pt_vars filled in so
+ that they are assigned a type tag. */
+
+ if (pi->pt_vars && !bitmap_empty_p (pi->pt_vars))
+ VEC_safe_push (tree, heap, with_ptvars, ptr);
+ else
+ set_pt_anything (ptr);
+ }
+
+ /* If we didn't find any pointers with pt_vars set, we're done. */
+ if (!with_ptvars)
+ return;
+
+ /* Now go through the pointers with pt_vars, and find a name tag
+ with the same pt_vars as this pointer, or create one if one
+ doesn't exist. */
+ for (i = 0; VEC_iterate (tree, with_ptvars, i, ptr); i++)
+ {
+ struct ptr_info_def *pi = SSA_NAME_PTR_INFO (ptr);
+ size_t j;
+ tree ptr2;
+ tree old_name_tag = pi->name_mem_tag;
+
+ /* If PTR points to a set of variables, check if we don't
+ have another pointer Q with the same points-to set before
+ creating a tag. If so, use Q's tag instead of creating a
+ new one.
+
+ This is important for not creating unnecessary symbols
+ and also for copy propagation. If we ever need to
+ propagate PTR into Q or vice-versa, we would run into
+ problems if they both had different name tags because
+ they would have different SSA version numbers (which
+ would force us to take the name tags in and out of SSA). */
+ for (j = 0; j < i && VEC_iterate (tree, with_ptvars, j, ptr2); j++)
{
- size_t j;
- tree old_name_tag = pi->name_mem_tag;
-
- /* If PTR points to a set of variables, check if we don't
- have another pointer Q with the same points-to set before
- creating a tag. If so, use Q's tag instead of creating a
- new one.
-
- This is important for not creating unnecessary symbols
- and also for copy propagation. If we ever need to
- propagate PTR into Q or vice-versa, we would run into
- problems if they both had different name tags because
- they would have different SSA version numbers (which
- would force us to take the name tags in and out of SSA). */
- for (j = 1; j < i; j++)
+ struct ptr_info_def *qi = SSA_NAME_PTR_INFO (ptr2);
+
+ if (bitmap_equal_p (pi->pt_vars, qi->pt_vars))
{
- tree q = ssa_name (j);
- struct ptr_info_def *qi;
-
- if (!q || !POINTER_TYPE_P (TREE_TYPE (q)))
- continue;
-
- qi = SSA_NAME_PTR_INFO (q);
-
- if (qi
- && qi->pt_vars
- && qi->name_mem_tag
- && bitmap_equal_p (pi->pt_vars, qi->pt_vars))
- {
- pi->name_mem_tag = qi->name_mem_tag;
- break;
- }
+ pi->name_mem_tag = qi->name_mem_tag;
+ break;
}
-
- /* If we didn't find a pointer with the same points-to set
- as PTR, create a new name tag if needed. */
- if (pi->name_mem_tag == NULL_TREE)
- pi->name_mem_tag = get_nmt_for (ptr);
-
- /* If the new name tag computed for PTR is different than
- the old name tag that it used to have, then the old tag
- needs to be removed from the IL, so we mark it for
- renaming. */
- if (old_name_tag && old_name_tag != pi->name_mem_tag)
- mark_sym_for_renaming (old_name_tag);
- }
- else
- {
- /* If the pointer does not point to a known spot, we should
- use type tags. */
- set_pt_anything (ptr);
- continue;
}
-
+
+ /* If we didn't find a pointer with the same points-to set
+ as PTR, create a new name tag if needed. */
+ if (pi->name_mem_tag == NULL_TREE)
+ pi->name_mem_tag = get_nmt_for (ptr);
+
+ /* If the new name tag computed for PTR is different than
+ the old name tag that it used to have, then the old tag
+ needs to be removed from the IL, so we mark it for
+ renaming. */
+ if (old_name_tag && old_name_tag != pi->name_mem_tag)
+ mark_sym_for_renaming (old_name_tag);
+
TREE_THIS_VOLATILE (pi->name_mem_tag)
- |= TREE_THIS_VOLATILE (TREE_TYPE (TREE_TYPE (ptr)));
-
+ |= TREE_THIS_VOLATILE (TREE_TYPE (TREE_TYPE (ptr)));
+
/* Mark the new name tag for renaming. */
mark_sym_for_renaming (pi->name_mem_tag);
}
+
+ VEC_free (tree, heap, with_ptvars);
}
alias_stats.tbaa_queries++;
- /* If VAR is a pointer with the same alias set as PTR, then dereferencing
- PTR can't possibly affect VAR. Note, that we are specifically testing
- for PTR's alias set here, not its pointed-to type. We also can't
- do this check with relaxed aliasing enabled. */
- if (POINTER_TYPE_P (TREE_TYPE (var))
- && var_alias_set != 0
- && mem_alias_set != 0)
- {
- HOST_WIDE_INT ptr_alias_set = get_alias_set (ptr);
- if (ptr_alias_set == var_alias_set)
- {
- alias_stats.alias_noalias++;
- alias_stats.tbaa_resolved++;
- return false;
- }
- }
-
/* If the alias sets don't conflict then MEM cannot alias VAR. */
if (!alias_sets_conflict_p (mem_alias_set, var_alias_set))
{
}
-/* Dump points-to info pointed by PTO into STDERR. */
+/* Dump points-to info pointed to by PTO into STDERR. */
void
debug_points_to_info (void)
}
+/* Given two symbols return TRUE if one is in the alias set of the other. */
+bool
+is_aliased_with (tree tag, tree sym)
+{
+ size_t i;
+ varray_type aliases;
+
+ if (var_ann (sym)->is_alias_tag)
+ {
+ aliases = var_ann (tag)->may_aliases;
+
+ if (aliases == NULL)
+ return false;
+
+ for (i = 0; i < VARRAY_ACTIVE_SIZE (aliases); i++)
+ if (VARRAY_TREE (aliases, i) == sym)
+ return true;
+ }
+ else
+ {
+ aliases = var_ann (sym)->may_aliases;
+
+ if (aliases == NULL)
+ return false;
+
+ for (i = 0; i < VARRAY_ACTIVE_SIZE (aliases); i++)
+ if (VARRAY_TREE (aliases, i) == tag)
+ return true;
+ }
+
+ return false;
+}
+
+
/* Add VAR to the list of may-aliases of PTR's type tag. If PTR
doesn't already have a type tag, create one. */
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