#include "ggc.h"
#include "flags.h"
#include "pointer-set.h"
+#include "target.h"
+#include "tree-iterator.h"
/* Fill array order with all nodes with output flag set in the reverse
topological order. */
#endif
varpool_reset_queue ();
for (node = cgraph_nodes; node; node = node->next)
- if (!cgraph_can_remove_if_no_direct_calls_and_refs_p (node)
+ if ((!cgraph_can_remove_if_no_direct_calls_and_refs_p (node)
+ /* Keep around virtual functions for possible devirtualization. */
+ || (!before_inlining_p
+ && !node->global.inlined_to
+ && DECL_VIRTUAL_P (node->decl)
+ && (DECL_COMDAT (node->decl) || DECL_EXTERNAL (node->decl))))
&& ((!DECL_EXTERNAL (node->decl))
|| before_inlining_p))
{
}
if (!node->aux)
{
+ struct cgraph_edge *e;
+ bool found = false;
+ int i;
+ struct ipa_ref *ref;
+
node->global.inlined_to = NULL;
if (file)
fprintf (file, " %s", cgraph_node_name (node));
- if (!node->analyzed || !DECL_EXTERNAL (node->decl) || before_inlining_p)
- cgraph_remove_node (node);
- else
+ /* See if there is reachable caller. */
+ for (e = node->callers; e && !found; e = e->next_caller)
+ if (e->caller->reachable)
+ found = true;
+ for (i = 0; (ipa_ref_list_refering_iterate (&node->ref_list, i, ref)
+ && !found); i++)
+ if (ref->refering_type == IPA_REF_CGRAPH
+ && ipa_ref_refering_node (ref)->reachable)
+ found = true;
+ else if (ref->refering_type == IPA_REF_VARPOOL
+ && ipa_ref_refering_varpool_node (ref)->needed)
+ found = true;
+
+ /* If so, we need to keep node in the callgraph. */
+ if (found || node->needed)
{
- struct cgraph_edge *e;
-
- /* See if there is reachable caller. */
- for (e = node->callers; e; e = e->next_caller)
- if (e->caller->reachable)
- break;
-
- /* If so, we need to keep node in the callgraph. */
- if (e || node->needed)
+ if (node->analyzed)
{
struct cgraph_node *clone;
if (!clone)
{
cgraph_release_function_body (node);
- node->analyzed = false;
node->local.inlinable = false;
+ if (node->prev_sibling_clone)
+ node->prev_sibling_clone->next_sibling_clone = node->next_sibling_clone;
+ else if (node->clone_of)
+ node->clone_of->clones = node->next_sibling_clone;
+ if (node->next_sibling_clone)
+ node->next_sibling_clone->prev_sibling_clone = node->prev_sibling_clone;
+ #ifdef ENABLE_CHECKING
+ if (node->clone_of)
+ node->former_clone_of = node->clone_of->decl;
+ #endif
+ node->clone_of = NULL;
+ node->next_sibling_clone = NULL;
+ node->prev_sibling_clone = NULL;
}
else
gcc_assert (!clone->in_other_partition);
+ node->analyzed = false;
+ changed = true;
cgraph_node_remove_callees (node);
ipa_remove_all_references (&node->ref_list);
- if (node->prev_sibling_clone)
- node->prev_sibling_clone->next_sibling_clone = node->next_sibling_clone;
- else if (node->clone_of)
- node->clone_of->clones = node->next_sibling_clone;
- if (node->next_sibling_clone)
- node->next_sibling_clone->prev_sibling_clone = node->prev_sibling_clone;
- node->clone_of = NULL;
- node->next_sibling_clone = NULL;
- node->prev_sibling_clone = NULL;
}
- else
- cgraph_remove_node (node);
}
- changed = true;
+ else
+ {
+ cgraph_remove_node (node);
+ changed = true;
+ }
}
}
for (node = cgraph_nodes; node; node = node->next)
if (aliased)
return true;
+ /* If linker counts on us, we must preserve the function. */
+ if (cgraph_used_from_object_file_p (node))
+ return true;
+ if (DECL_PRESERVE_P (node->decl))
+ return true;
+ if (lookup_attribute ("externally_visible", DECL_ATTRIBUTES (node->decl)))
+ return true;
+
/* When doing link time optimizations, hidden symbols become local. */
- if (in_lto_p && DECL_VISIBILITY (node->decl) == VISIBILITY_HIDDEN
+ if (in_lto_p
+ && (DECL_VISIBILITY (node->decl) == VISIBILITY_HIDDEN
+ || DECL_VISIBILITY (node->decl) == VISIBILITY_INTERNAL)
/* Be sure that node is defined in IR file, not in other object
file. In that case we don't set used_from_other_object_file. */
&& node->analyzed)
return true;
}
}
- if (node->local.used_from_object_file)
+
+ if (MAIN_NAME_P (DECL_NAME (node->decl)))
return true;
- if (DECL_PRESERVE_P (node->decl))
+
+ return false;
+}
+
+/* Return true when variable VNODE should be considered externally visible. */
+
+static bool
+varpool_externally_visible_p (struct varpool_node *vnode, bool aliased)
+{
+ if (!DECL_COMDAT (vnode->decl) && !TREE_PUBLIC (vnode->decl))
+ return false;
+
+ /* Do not even try to be smart about aliased nodes. Until we properly
+ represent everything by same body alias, these are just evil. */
+ if (aliased)
return true;
- if (MAIN_NAME_P (DECL_NAME (node->decl)))
+
+ /* If linker counts on us, we must preserve the function. */
+ if (varpool_used_from_object_file_p (vnode))
return true;
- if (lookup_attribute ("externally_visible", DECL_ATTRIBUTES (node->decl)))
+
+ if (DECL_PRESERVE_P (vnode->decl))
+ return true;
+ if (lookup_attribute ("externally_visible",
+ DECL_ATTRIBUTES (vnode->decl)))
+ return true;
+
+ /* See if we have linker information about symbol not being used or
+ if we need to make guess based on the declaration.
+
+ Even if the linker clams the symbol is unused, never bring internal
+ symbols that are declared by user as used or externally visible.
+ This is needed for i.e. references from asm statements. */
+ if (varpool_used_from_object_file_p (vnode))
+ return true;
+
+ /* When doing link time optimizations, hidden symbols become local. */
+ if (in_lto_p
+ && (DECL_VISIBILITY (vnode->decl) == VISIBILITY_HIDDEN
+ || DECL_VISIBILITY (vnode->decl) == VISIBILITY_INTERNAL)
+ /* Be sure that node is defined in IR file, not in other object
+ file. In that case we don't set used_from_other_object_file. */
+ && vnode->finalized)
+ ;
+ else if (!flag_whole_program)
+ return true;
+
+ /* Do not attempt to privatize COMDATS by default.
+ This would break linking with C++ libraries sharing
+ inline definitions.
+
+ FIXME: We can do so for readonly vars with no address taken and
+ possibly also for vtables since no direct pointer comparsion is done.
+ It might be interesting to do so to reduce linking overhead. */
+ if (DECL_COMDAT (vnode->decl) || DECL_WEAK (vnode->decl))
return true;
return false;
}
alias_pair *p;
/* Discover aliased nodes. */
- for (i = 0; VEC_iterate (alias_pair, alias_pairs, i, p); i++)
+ FOR_EACH_VEC_ELT (alias_pair, alias_pairs, i, p)
{
if (dump_file)
fprintf (dump_file, "Alias %s->%s",
struct cgraph_node *alias;
gcc_assert (whole_program || in_lto_p || !TREE_PUBLIC (node->decl));
cgraph_make_decl_local (node->decl);
+ node->resolution = LDPR_PREVAILING_DEF_IRONLY;
for (alias = node->same_body; alias; alias = alias->next)
cgraph_make_decl_local (alias->decl);
if (node->same_comdat_group)
if (!vnode->finalized)
continue;
if (vnode->needed
- && (DECL_COMDAT (vnode->decl) || TREE_PUBLIC (vnode->decl))
- && (((!whole_program
- /* We can privatize comdat readonly variables whose address is
- not taken, but doing so is not going to bring us
- optimization oppurtunities until we start reordering
- datastructures. */
- || DECL_COMDAT (vnode->decl)
- || DECL_WEAK (vnode->decl))
- /* When doing linktime optimizations, all hidden symbols will
- become local. */
- && (!in_lto_p
- || DECL_VISIBILITY (vnode->decl) != VISIBILITY_HIDDEN
- /* We can get prevailing decision in other object file.
- In this case we do not sed used_from_object_file. */
- || !vnode->finalized))
- || vnode->used_from_object_file
- || pointer_set_contains (aliased_vnodes, vnode)
- || lookup_attribute ("externally_visible",
- DECL_ATTRIBUTES (vnode->decl))))
+ && varpool_externally_visible_p
+ (vnode,
+ pointer_set_contains (aliased_vnodes, vnode)))
vnode->externally_visible = true;
else
vnode->externally_visible = false;
{
gcc_assert (in_lto_p || whole_program || !TREE_PUBLIC (vnode->decl));
cgraph_make_decl_local (vnode->decl);
+ vnode->resolution = LDPR_PREVAILING_DEF_IRONLY;
}
gcc_assert (TREE_STATIC (vnode->decl));
}
NULL, /* function_transform */
NULL /* variable_transform */
};
+
+/* Generate and emit a static constructor or destructor. WHICH must
+ be one of 'I' (for a constructor) or 'D' (for a destructor). BODY
+ is a STATEMENT_LIST containing GENERIC statements. PRIORITY is the
+ initialization priority for this constructor or destructor. */
+
+void
+cgraph_build_static_cdtor (char which, tree body, int priority)
+{
+ static int counter = 0;
+ char which_buf[16];
+ tree decl, name, resdecl;
+
+ /* The priority is encoded in the constructor or destructor name.
+ collect2 will sort the names and arrange that they are called at
+ program startup. */
+ sprintf (which_buf, "%c_%.5d_%d", which, priority, counter++);
+ name = get_file_function_name (which_buf);
+
+ decl = build_decl (input_location, FUNCTION_DECL, name,
+ build_function_type_list (void_type_node, NULL_TREE));
+ current_function_decl = decl;
+
+ resdecl = build_decl (input_location,
+ RESULT_DECL, NULL_TREE, void_type_node);
+ DECL_ARTIFICIAL (resdecl) = 1;
+ DECL_RESULT (decl) = resdecl;
+ DECL_CONTEXT (resdecl) = decl;
+
+ allocate_struct_function (decl, false);
+
+ TREE_STATIC (decl) = 1;
+ TREE_USED (decl) = 1;
+ DECL_ARTIFICIAL (decl) = 1;
+ DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (decl) = 1;
+ DECL_SAVED_TREE (decl) = body;
+ if (!targetm.have_ctors_dtors)
+ {
+ TREE_PUBLIC (decl) = 1;
+ DECL_PRESERVE_P (decl) = 1;
+ }
+ DECL_UNINLINABLE (decl) = 1;
+
+ DECL_INITIAL (decl) = make_node (BLOCK);
+ TREE_USED (DECL_INITIAL (decl)) = 1;
+
+ DECL_SOURCE_LOCATION (decl) = input_location;
+ cfun->function_end_locus = input_location;
+
+ switch (which)
+ {
+ case 'I':
+ DECL_STATIC_CONSTRUCTOR (decl) = 1;
+ decl_init_priority_insert (decl, priority);
+ break;
+ case 'D':
+ DECL_STATIC_DESTRUCTOR (decl) = 1;
+ decl_fini_priority_insert (decl, priority);
+ break;
+ default:
+ gcc_unreachable ();
+ }
+
+ gimplify_function_tree (decl);
+
+ cgraph_add_new_function (decl, false);
+
+ set_cfun (NULL);
+ current_function_decl = NULL;
+}
+
+
+/* A vector of FUNCTION_DECLs declared as static constructors. */
+static VEC(tree, heap) *static_ctors;
+/* A vector of FUNCTION_DECLs declared as static destructors. */
+static VEC(tree, heap) *static_dtors;
+
+/* When target does not have ctors and dtors, we call all constructor
+ and destructor by special initialization/destruction function
+ recognized by collect2.
+
+ When we are going to build this function, collect all constructors and
+ destructors and turn them into normal functions. */
+
+static void
+record_cdtor_fn (struct cgraph_node *node)
+{
+ if (DECL_STATIC_CONSTRUCTOR (node->decl))
+ VEC_safe_push (tree, heap, static_ctors, node->decl);
+ if (DECL_STATIC_DESTRUCTOR (node->decl))
+ VEC_safe_push (tree, heap, static_dtors, node->decl);
+ node = cgraph_node (node->decl);
+ node->local.disregard_inline_limits = 1;
+}
+
+/* Define global constructors/destructor functions for the CDTORS, of
+ which they are LEN. The CDTORS are sorted by initialization
+ priority. If CTOR_P is true, these are constructors; otherwise,
+ they are destructors. */
+
+static void
+build_cdtor (bool ctor_p, VEC (tree, heap) *cdtors)
+{
+ size_t i,j;
+ size_t len = VEC_length (tree, cdtors);
+
+ i = 0;
+ while (i < len)
+ {
+ tree body;
+ tree fn;
+ priority_type priority;
+
+ priority = 0;
+ body = NULL_TREE;
+ j = i;
+ do
+ {
+ priority_type p;
+ fn = VEC_index (tree, cdtors, j);
+ p = ctor_p ? DECL_INIT_PRIORITY (fn) : DECL_FINI_PRIORITY (fn);
+ if (j == i)
+ priority = p;
+ else if (p != priority)
+ break;
+ j++;
+ }
+ while (j < len);
+
+ /* When there is only one cdtor and target supports them, do nothing. */
+ if (j == i + 1
+ && targetm.have_ctors_dtors)
+ {
+ i++;
+ continue;
+ }
+ /* Find the next batch of constructors/destructors with the same
+ initialization priority. */
+ for (;i < j; i++)
+ {
+ tree call;
+ fn = VEC_index (tree, cdtors, i);
+ call = build_call_expr (fn, 0);
+ if (ctor_p)
+ DECL_STATIC_CONSTRUCTOR (fn) = 0;
+ else
+ DECL_STATIC_DESTRUCTOR (fn) = 0;
+ /* We do not want to optimize away pure/const calls here.
+ When optimizing, these should be already removed, when not
+ optimizing, we want user to be able to breakpoint in them. */
+ TREE_SIDE_EFFECTS (call) = 1;
+ append_to_statement_list (call, &body);
+ }
+ gcc_assert (body != NULL_TREE);
+ /* Generate a function to call all the function of like
+ priority. */
+ cgraph_build_static_cdtor (ctor_p ? 'I' : 'D', body, priority);
+ }
+}
+
+/* Comparison function for qsort. P1 and P2 are actually of type
+ "tree *" and point to static constructors. DECL_INIT_PRIORITY is
+ used to determine the sort order. */
+
+static int
+compare_ctor (const void *p1, const void *p2)
+{
+ tree f1;
+ tree f2;
+ int priority1;
+ int priority2;
+
+ f1 = *(const tree *)p1;
+ f2 = *(const tree *)p2;
+ priority1 = DECL_INIT_PRIORITY (f1);
+ priority2 = DECL_INIT_PRIORITY (f2);
+
+ if (priority1 < priority2)
+ return -1;
+ else if (priority1 > priority2)
+ return 1;
+ else
+ /* Ensure a stable sort. Constructors are executed in backwarding
+ order to make LTO initialize braries first. */
+ return DECL_UID (f2) - DECL_UID (f1);
+}
+
+/* Comparison function for qsort. P1 and P2 are actually of type
+ "tree *" and point to static destructors. DECL_FINI_PRIORITY is
+ used to determine the sort order. */
+
+static int
+compare_dtor (const void *p1, const void *p2)
+{
+ tree f1;
+ tree f2;
+ int priority1;
+ int priority2;
+
+ f1 = *(const tree *)p1;
+ f2 = *(const tree *)p2;
+ priority1 = DECL_FINI_PRIORITY (f1);
+ priority2 = DECL_FINI_PRIORITY (f2);
+
+ if (priority1 < priority2)
+ return -1;
+ else if (priority1 > priority2)
+ return 1;
+ else
+ /* Ensure a stable sort. */
+ return DECL_UID (f1) - DECL_UID (f2);
+}
+
+/* Generate functions to call static constructors and destructors
+ for targets that do not support .ctors/.dtors sections. These
+ functions have magic names which are detected by collect2. */
+
+static void
+build_cdtor_fns (void)
+{
+ if (!VEC_empty (tree, static_ctors))
+ {
+ gcc_assert (!targetm.have_ctors_dtors || in_lto_p);
+ VEC_qsort (tree, static_ctors, compare_ctor);
+ build_cdtor (/*ctor_p=*/true, static_ctors);
+ }
+
+ if (!VEC_empty (tree, static_dtors))
+ {
+ gcc_assert (!targetm.have_ctors_dtors || in_lto_p);
+ VEC_qsort (tree, static_dtors, compare_dtor);
+ build_cdtor (/*ctor_p=*/false, static_dtors);
+ }
+}
+
+/* Look for constructors and destructors and produce function calling them.
+ This is needed for targets not supporting ctors or dtors, but we perform the
+ transformation also at linktime to merge possibly numberous
+ constructors/destructors into single function to improve code locality and
+ reduce size. */
+
+static unsigned int
+ipa_cdtor_merge (void)
+{
+ struct cgraph_node *node;
+ for (node = cgraph_nodes; node; node = node->next)
+ if (node->analyzed
+ && (DECL_STATIC_CONSTRUCTOR (node->decl)
+ || DECL_STATIC_DESTRUCTOR (node->decl)))
+ record_cdtor_fn (node);
+ build_cdtor_fns ();
+ VEC_free (tree, heap, static_ctors);
+ VEC_free (tree, heap, static_dtors);
+ return 0;
+}
+
+/* Perform the pass when we have no ctors/dtors support
+ or at LTO time to merge multiple constructors into single
+ function. */
+
+static bool
+gate_ipa_cdtor_merge (void)
+{
+ return !targetm.have_ctors_dtors || (optimize && in_lto_p);
+}
+
+struct ipa_opt_pass_d pass_ipa_cdtor_merge =
+{
+ {
+ IPA_PASS,
+ "cdtor", /* name */
+ gate_ipa_cdtor_merge, /* gate */
+ ipa_cdtor_merge, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_CGRAPHOPT, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ 0 /* todo_flags_finish */
+ },
+ NULL, /* generate_summary */
+ NULL, /* write_summary */
+ NULL, /* read_summary */
+ NULL, /* write_optimization_summary */
+ NULL, /* read_optimization_summary */
+ NULL, /* stmt_fixup */
+ 0, /* TODOs */
+ NULL, /* function_transform */
+ NULL /* variable_transform */
+};
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