void
insert_debug_temp_for_var_def (gimple_stmt_iterator *gsi, tree var)
{
imm_use_iterator imm_iter;
use_operand_p use_p;
gimple *stmt;
gimple *def_stmt = NULL;
int usecount = 0;
tree value = NULL;
if (!MAY_HAVE_DEBUG_STMTS)
return;
/* If this name has already been registered for replacement, do nothing
as anything that uses this name isn't in SSA form. */
if (name_registered_for_update_p (var))
return;
/* Check whether there are debug stmts that reference this variable and,
if there are, decide whether we should use a debug temp. */
FOR_EACH_IMM_USE_FAST (use_p, imm_iter, var)
{
stmt = USE_STMT (use_p);
if (!gimple_debug_bind_p (stmt))
continue;
if (usecount++)
break;
if (gimple_debug_bind_get_value (stmt) != var)
{
/* Count this as an additional use, so as to make sure we
use a temp unless VAR's definition has a SINGLE_RHS that
can be shared. */
usecount++;
break;
}
}
void
release_ssa_name (tree var)
{
if (!var)
return;
/* Never release the default definition for a symbol. It's a
special SSA name that should always exist once it's created. */
if (SSA_NAME_IS_DEFAULT_DEF (var))
return;
/* If VAR has been registered for SSA updating, don't remove it.
After update_ssa has run, the name will be released. */
if (name_registered_for_update_p (var))
{
release_ssa_name_after_update_ssa (var);
return;
}
/* release_ssa_name can be called multiple times on a single SSA_NAME.
However, it should only end up on our free list one time. We
keep a status bit in the SSA_NAME node itself to indicate it has
been put on the free list.
Note that once on the freelist you can not reference the SSA_NAME's
defining statement. */
if (! SSA_NAME_IN_FREE_LIST (var))
{
tree saved_ssa_name_var = SSA_NAME_VAR (var);
int saved_ssa_name_version = SSA_NAME_VERSION (var);
use_operand_p imm = &(SSA_NAME_IMM_USE_NODE (var));
if (MAY_HAVE_DEBUG_STMTS)
insert_debug_temp_for_var_def (NULL, var);
#ifdef ENABLE_CHECKING
verify_imm_links (stderr, var);
#endif
while (imm->next != imm)
delink_imm_use (imm->next);
(*SSANAMES (cfun))[SSA_NAME_VERSION (var)] = NULL_TREE;
memset (var, 0, tree_size (var));
imm->prev = imm;
imm->next = imm;
imm->loc.ssa_name = var;
/* First put back the right tree node so that the tree checking
macros do not complain. */
TREE_SET_CODE (var, SSA_NAME);
/* Restore the version number. */
SSA_NAME_VERSION (var) = saved_ssa_name_version;
/* Hopefully this can go away once we have the new incremental
SSA updating code installed. */
SET_SSA_NAME_VAR_OR_IDENTIFIER (var, saved_ssa_name_var);
/* Note this SSA_NAME is now in the first list. */
SSA_NAME_IN_FREE_LIST (var) = 1;
/* And finally put it on the free list. */
vec_safe_push (FREE_SSANAMES (cfun), var);
}
}
