/* Mark DECL as finalized. By finalizing the declaration, frontend instruct the
middle end to output the variable to asm file, if needed or externally
visible. */
void
varpool_finalize_decl (tree decl)
{
struct varpool_node *node = varpool_node (decl);
gcc_assert (TREE_STATIC (decl));
/* The first declaration of a variable that comes through this function
decides whether it is global (in C, has external linkage)
or local (in C, has internal linkage). So do nothing more
if this function has already run. */
if (node->finalized)
{
if (cgraph_global_info_ready)
varpool_assemble_pending_decls ();
return;
}
if (node->needed)
varpool_enqueue_needed_node (node);
node->finalized = true;
if (TREE_THIS_VOLATILE (decl) || DECL_PRESERVE_P (decl)
/* Traditionally we do not eliminate static variables when not
optimizing and when not doing toplevel reoder. */
|| (!flag_toplevel_reorder && !DECL_COMDAT (node->symbol.decl)
&& !DECL_ARTIFICIAL (node->symbol.decl)))
node->symbol.force_output = true;
if (decide_is_variable_needed (node, decl))
varpool_mark_needed_node (node);
if (cgraph_global_info_ready)
varpool_assemble_pending_decls ();
}
/* Mark DECL as finalized. By finalizing the declaration, frontend instruct the
middle end to output the variable to asm file, if needed or externally
visible. */
void
varpool_finalize_decl (tree decl)
{
struct varpool_node *node = varpool_node (decl);
gcc_assert (TREE_STATIC (decl));
/* The first declaration of a variable that comes through this function
decides whether it is global (in C, has external linkage)
or local (in C, has internal linkage). So do nothing more
if this function has already run. */
if (node->finalized)
{
if (cgraph_global_info_ready)
varpool_assemble_pending_decls ();
return;
}
if (node->needed)
varpool_enqueue_needed_node (node);
node->finalized = true;
if (TREE_THIS_VOLATILE (decl) || DECL_PRESERVE_P (decl))
node->force_output = true;
if (decide_is_variable_needed (node, decl))
varpool_mark_needed_node (node);
if (cgraph_global_info_ready)
varpool_assemble_pending_decls ();
}
/* Optimization of function bodies might've rendered some variables as
unnecessary so we want to avoid these from being compiled.
This is done by pruning the queue and keeping only the variables that
really appear needed (ie they are either externally visible or referenced
by compiled function). Re-doing the reachability analysis on variables
brings back the remaining variables referenced by these. */
void
varpool_remove_unreferenced_decls (void)
{
struct varpool_node *next, *node = varpool_nodes_queue;
varpool_reset_queue ();
if (errorcount || sorrycount)
return;
while (node)
{
tree decl = node->decl;
next = node->next_needed;
node->needed = 0;
if (node->finalized
&& (decide_is_variable_needed (node, decl)
/* ??? Cgraph does not yet rule the world with an iron hand,
and does not control the emission of debug information.
After a variable has its DECL_RTL set, we must assume that
it may be referenced by the debug information, and we can
no longer elide it. */
|| DECL_RTL_SET_P (decl)))
varpool_mark_needed_node (node);
node = next;
}
/* Make sure we mark alias targets as used targets. */
finish_aliases_1 ();
varpool_analyze_pending_decls ();
}
/* Mark DECL as finalized. By finalizing the declaration, frontend instruct the
middle end to output the variable to asm file, if needed or externally
visible. */
void
varpool_finalize_decl (tree decl)
{
struct varpool_node *node = varpool_node (decl);
/* The first declaration of a variable that comes through this function
decides whether it is global (in C, has external linkage)
or local (in C, has internal linkage). So do nothing more
if this function has already run. */
if (node->finalized)
{
if (cgraph_global_info_ready)
varpool_assemble_pending_decls ();
return;
}
if (node->needed)
varpool_enqueue_needed_node (node);
node->finalized = true;
if (decide_is_variable_needed (node, decl))
varpool_mark_needed_node (node);
/* Since we reclaim unreachable nodes at the end of every language
level unit, we need to be conservative about possible entry points
there. */
else if (TREE_PUBLIC (decl) && !DECL_COMDAT (decl) && !DECL_EXTERNAL (decl))
varpool_mark_needed_node (node);
if (cgraph_global_info_ready)
varpool_assemble_pending_decls ();
}
struct varpool_node *
varpool_create_variable_alias (tree alias, tree decl)
{
struct varpool_node *alias_node;
gcc_assert (TREE_CODE (decl) == VAR_DECL);
gcc_assert (TREE_CODE (alias) == VAR_DECL);
alias_node = varpool_node (alias);
alias_node->alias = 1;
alias_node->finalized = 1;
alias_node->alias_of = decl;
if ((!DECL_EXTERNAL (alias)
&& decide_is_variable_needed (alias_node, alias))
|| alias_node->needed)
varpool_mark_needed_node (alias_node);
return alias_node;
}
/* Determine if variable DECL is needed. That is, visible to something
either outside this translation unit, something magic in the system
configury */
bool
decide_is_variable_needed (struct varpool_node *node, tree decl)
{
/* If the user told us it is used, then it must be so. */
if ((node->externally_visible && !DECL_COMDAT (decl))
|| node->force_output)
return true;
/* ??? If the assembler name is set by hand, it is possible to assemble
the name later after finalizing the function and the fact is noticed
in assemble_name then. This is arguably a bug. */
if (DECL_ASSEMBLER_NAME_SET_P (decl)
&& TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)))
return true;
/* Externally visible variables must be output. The exception is
COMDAT variables that must be output only when they are needed. */
if (TREE_PUBLIC (decl)
&& !flag_whole_program
&& !flag_lto
&& !flag_whopr
&& !DECL_COMDAT (decl)
&& !DECL_EXTERNAL (decl))
return true;
/* When emulating tls, we actually see references to the control
variable, rather than the user-level variable. */
if (!targetm.have_tls
&& TREE_CODE (decl) == VAR_DECL
&& DECL_THREAD_LOCAL_P (decl))
{
tree control = emutls_decl (decl);
if (decide_is_variable_needed (varpool_node (control), control))
return true;
}
/* When not reordering top level variables, we have to assume that
we are going to keep everything. */
if (flag_toplevel_reorder)
return false;
/* We want to emit COMDAT variables only when absolutely necessary. */
if (DECL_COMDAT (decl))
return false;
return true;
}
/* Mark DECL as finalized. By finalizing the declaration, frontend instruct the
middle end to output the variable to asm file, if needed or externally
visible. */
void
varpool_finalize_decl (tree decl)
{
struct varpool_node *node = varpool_node (decl);
/* FIXME: We don't really stream varpool datastructure and instead rebuild it
by varpool_finalize_decl. This is not quite correct since this way we can't
attach any info to varpool. Eventually we will want to stream varpool nodes
and the flags.
For the moment just prevent analysis of varpool nodes to happen again, so
we will re-try to compute "address_taken" flag of varpool that breaks
in presence of clones. */
if (in_lto_p)
node->analyzed = true;
/* The first declaration of a variable that comes through this function
decides whether it is global (in C, has external linkage)
or local (in C, has internal linkage). So do nothing more
if this function has already run. */
if (node->finalized)
{
if (cgraph_global_info_ready)
varpool_assemble_pending_decls ();
return;
}
if (node->needed)
varpool_enqueue_needed_node (node);
node->finalized = true;
if (decide_is_variable_needed (node, decl))
varpool_mark_needed_node (node);
/* Since we reclaim unreachable nodes at the end of every language
level unit, we need to be conservative about possible entry points
there. */
else if (TREE_PUBLIC (decl) && !DECL_COMDAT (decl) && !DECL_EXTERNAL (decl))
varpool_mark_needed_node (node);
if (cgraph_global_info_ready)
varpool_assemble_pending_decls ();
}
