static void add_referenced_var (tree, struct walk_state *);
static void compute_immediate_uses_for_phi (tree, bool (*)(tree));
static void compute_immediate_uses_for_stmt (tree, int, bool (*)(tree));
-static void find_hidden_use_vars (tree);
-static tree find_hidden_use_vars_r (tree *, int *, void *);
/* Global declarations. */
basic_block bb;
block_stmt_iterator si;
struct walk_state walk_state;
- tree block;
-
- /* Walk the lexical blocks in the function looking for variables that may
- have been used to declare VLAs and for nested functions. Both
- constructs create hidden uses of variables.
-
- Note that at this point we may have multiple blocks hung off
- DECL_INITIAL chained through the BLOCK_CHAIN field due to
- how inlining works. Egad. */
- block = DECL_INITIAL (current_function_decl);
- while (block)
- {
- find_hidden_use_vars (block);
- block = BLOCK_CHAIN (block);
- }
vars_found = htab_create (50, htab_hash_pointer, htab_eq_pointer, NULL);
memset (&walk_state, 0, sizeof (walk_state));
fprintf (file, ", UID %u", (unsigned) ann->uid);
- if (ann->has_hidden_use)
- fprintf (file, ", has hidden uses");
-
if (ann->type_mem_tag)
{
fprintf (file, ", type memory tag: ");
return var;
}
-
-/* Mark variables in BLOCK that have hidden uses. A hidden use can
- occur due to VLA declarations or nested functions. */
-
-static void
-find_hidden_use_vars (tree block)
-{
- tree sub, decl, tem;
-
- /* Check all the arrays declared in the block for VLAs.
- While scanning the block's variables, also see if there is
- a nested function at this scope. */
- for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
- {
- int inside_vla = 0;
- walk_tree (&decl, find_hidden_use_vars_r, &inside_vla, NULL);
- }
-
- /* Now repeat the search in any sub-blocks. */
- for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
- find_hidden_use_vars (sub);
-
- /* A VLA parameter may use a variable which as set from another
- parameter to declare the size of the VLA. We need to mark the
- variable as having a hidden use since it is used to declare the
- VLA parameter and that declaration is not seen by the SSA code.
-
- Note get_pending_sizes clears the PENDING_SIZES chain, so we
- must restore it. */
- tem = get_pending_sizes ();
- put_pending_sizes (tem);
- for (; tem; tem = TREE_CHAIN (tem))
- {
- int inside_vla = 1;
- walk_tree (&TREE_VALUE (tem), find_hidden_use_vars_r, &inside_vla, NULL);
- }
-}
-
-
-/* Callback for walk_tree used by find_hidden_use_vars to analyze each
- variable in a lexical block. If the variable's size has a variable
- size, then mark all objects needed to compute the variable's size
- as having hidden uses. */
-
-static tree
-find_hidden_use_vars_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
- void *data ATTRIBUTE_UNUSED)
-{
- int *inside_vla = (int *) data;
-
- /* We need to look for hidden uses due to VLAs in variable
- definitions. We originally used to look for these hidden
- uses in the variable's type, but that's unreliable if the
- type's size contains a SAVE_EXPR for a different function
- context than the variable is used within. */
- if (SSA_VAR_P (*tp)
- && ((DECL_SIZE (*tp)
- && ! really_constant_p (DECL_SIZE (*tp)))
- || (DECL_SIZE_UNIT (*tp)
- && ! really_constant_p (DECL_SIZE_UNIT (*tp)))))
- {
- int save = *inside_vla;
-
- *inside_vla = 1;
- walk_tree (&DECL_SIZE (*tp), find_hidden_use_vars_r, inside_vla, NULL);
- walk_tree (&DECL_SIZE_UNIT (*tp), find_hidden_use_vars_r,
- inside_vla, NULL);
- *inside_vla = save;
- }
- else if (*inside_vla && SSA_VAR_P (*tp))
- set_has_hidden_use (*tp);
-
- return NULL_TREE;
-}
-
-
/* Add a temporary variable to REFERENCED_VARS. This is similar to
add_referenced_var, but is used by passes that need to add new temps to
the REFERENCED_VARS array after the program has been scanned for
OSDN Git Service
