/* Basic IPA optimizations and utilities.
- Copyright (C) 2003-2014 Free Software Foundation, Inc.
+ Copyright (C) 2003-2018 Free Software Foundation, Inc.
This file is part of GCC.
#include "config.h"
#include "system.h"
#include "coretypes.h"
-#include "tm.h"
+#include "backend.h"
+#include "target.h"
#include "tree.h"
-#include "calls.h"
+#include "gimple.h"
+#include "alloc-pool.h"
+#include "tree-pass.h"
#include "stringpool.h"
#include "cgraph.h"
-#include "tree-pass.h"
-#include "pointer-set.h"
-#include "gimple-expr.h"
#include "gimplify.h"
-#include "flags.h"
-#include "target.h"
#include "tree-iterator.h"
#include "ipa-utils.h"
-#include "ipa-inline.h"
-#include "tree-inline.h"
-#include "profile.h"
-#include "params.h"
-
-/* Return true when NODE can not be local. Worker for cgraph_local_node_p. */
-
-static bool
-cgraph_non_local_node_p_1 (struct cgraph_node *node, void *data ATTRIBUTE_UNUSED)
-{
- /* FIXME: Aliases can be local, but i386 gets thunks wrong then. */
- return !(cgraph_only_called_directly_or_aliased_p (node)
- && !ipa_ref_has_aliases_p (&node->ref_list)
- && node->definition
- && !DECL_EXTERNAL (node->decl)
- && !node->externally_visible
- && !node->used_from_other_partition
- && !node->in_other_partition);
-}
-
-/* Return true when function can be marked local. */
-
-static bool
-cgraph_local_node_p (struct cgraph_node *node)
-{
- struct cgraph_node *n = cgraph_function_or_thunk_node (node, NULL);
-
- /* FIXME: thunks can be considered local, but we need prevent i386
- from attempting to change calling convention of them. */
- if (n->thunk.thunk_p)
- return false;
- return !cgraph_for_node_and_aliases (n,
- cgraph_non_local_node_p_1, NULL, true);
-
-}
+#include "symbol-summary.h"
+#include "tree-vrp.h"
+#include "ipa-prop.h"
+#include "ipa-fnsummary.h"
+#include "dbgcnt.h"
+#include "debug.h"
+#include "stringpool.h"
+#include "attribs.h"
/* Return true when NODE has ADDR reference. */
static bool
has_addr_references_p (struct cgraph_node *node,
- void *data ATTRIBUTE_UNUSED)
+ void *)
{
int i;
- struct ipa_ref *ref;
+ struct ipa_ref *ref = NULL;
- for (i = 0; ipa_ref_list_referring_iterate (&node->ref_list,
- i, ref); i++)
+ for (i = 0; node->iterate_referring (i, ref); i++)
if (ref->use == IPA_REF_ADDR)
return true;
return false;
}
+/* Return true when NODE can be target of an indirect call. */
+
+static bool
+is_indirect_call_target_p (struct cgraph_node *node, void *)
+{
+ return node->indirect_call_target;
+}
+
/* Look for all functions inlined to NODE and update their inlined_to pointers
to INLINED_TO. */
static void
enqueue_node (symtab_node *node, symtab_node **first,
- struct pointer_set_t *reachable)
+ hash_set<symtab_node *> *reachable)
{
/* Node is still in queue; do nothing. */
if (node->aux && node->aux != (void *) 2)
return;
/* Node was already processed as unreachable, re-enqueue
only if it became reachable now. */
- if (node->aux == (void *)2 && !pointer_set_contains (reachable, node))
+ if (node->aux == (void *)2 && !reachable->contains (node))
return;
node->aux = *first;
*first = node;
}
+/* Return true if NODE may get inlined later.
+ This is used to keep DECL_EXTERNAL function bodies around long enough
+ so inliner can proces them. */
+
+static bool
+possible_inline_candidate_p (symtab_node *node)
+{
+ if (symtab->state >= IPA_SSA_AFTER_INLINING)
+ return false;
+ cgraph_node *cnode = dyn_cast <cgraph_node *> (node);
+ if (!cnode)
+ return false;
+ if (DECL_UNINLINABLE (cnode->decl))
+ return false;
+ if (opt_for_fn (cnode->decl, optimize))
+ return true;
+ if (symtab->state >= IPA_SSA)
+ return false;
+ return lookup_attribute ("always_inline", DECL_ATTRIBUTES (node->decl));
+}
+
/* Process references. */
static void
-process_references (struct ipa_ref_list *list,
+process_references (symtab_node *snode,
symtab_node **first,
- bool before_inlining_p,
- struct pointer_set_t *reachable)
+ hash_set<symtab_node *> *reachable)
{
int i;
- struct ipa_ref *ref;
- for (i = 0; ipa_ref_list_reference_iterate (list, i, ref); i++)
+ struct ipa_ref *ref = NULL;
+ for (i = 0; snode->iterate_reference (i, ref); i++)
{
symtab_node *node = ref->referred;
+ symtab_node *body = node->ultimate_alias_target ();
if (node->definition && !node->in_other_partition
&& ((!DECL_EXTERNAL (node->decl) || node->alias)
- || (before_inlining_p
- /* We use variable constructors during late complation for
+ || (possible_inline_candidate_p (node)
+ /* We use variable constructors during late compilation for
constant folding. Keep references alive so partitioning
knows about potential references. */
- || (TREE_CODE (node->decl) == VAR_DECL
- && flag_wpa
- && ctor_for_folding (node->decl)
- != error_mark_node))))
- pointer_set_insert (reachable, node);
+ || (VAR_P (node->decl)
+ && (flag_wpa
+ || flag_incremental_link
+ == INCREMENTAL_LINK_LTO)
+ && dyn_cast <varpool_node *> (node)
+ ->ctor_useable_for_folding_p ()))))
+ {
+ /* Be sure that we will not optimize out alias target
+ body. */
+ if (DECL_EXTERNAL (node->decl)
+ && node->alias
+ && symtab->state < IPA_SSA_AFTER_INLINING)
+ reachable->add (body);
+ reachable->add (node);
+ }
enqueue_node (node, first, reachable);
}
}
possible. */
static void
-walk_polymorphic_call_targets (pointer_set_t *reachable_call_targets,
+walk_polymorphic_call_targets (hash_set<void *> *reachable_call_targets,
struct cgraph_edge *edge,
symtab_node **first,
- pointer_set_t *reachable, bool before_inlining_p)
+ hash_set<symtab_node *> *reachable)
{
unsigned int i;
void *cache_token;
= possible_polymorphic_call_targets
(edge, &final, &cache_token);
- if (!pointer_set_insert (reachable_call_targets,
- cache_token))
+ if (!reachable_call_targets->add (cache_token))
{
for (i = 0; i < targets.length (); i++)
{
unused. */
if (TREE_CODE (TREE_TYPE (n->decl)) == METHOD_TYPE
&& type_in_anonymous_namespace_p
- (method_class_type (TREE_TYPE (n->decl))))
+ (TYPE_METHOD_BASETYPE (TREE_TYPE (n->decl))))
continue;
+ n->indirect_call_target = true;
+ symtab_node *body = n->function_symbol ();
+
/* Prior inlining, keep alive bodies of possible targets for
devirtualization. */
- if (n->definition
- && before_inlining_p)
- pointer_set_insert (reachable, n);
-
+ if (n->definition
+ && (possible_inline_candidate_p (body)
+ && opt_for_fn (body->decl, flag_devirtualize)))
+ {
+ /* Be sure that we will not optimize out alias target
+ body. */
+ if (DECL_EXTERNAL (n->decl)
+ && n->alias
+ && symtab->state < IPA_SSA_AFTER_INLINING)
+ reachable->add (body);
+ reachable->add (n);
+ }
/* Even after inlining we want to keep the possible targets in the
boundary, so late passes can still produce direct call even if
the chance for inlining is lost. */
make the edge direct. */
if (final)
{
- if (targets.length () <= 1)
+ if (targets.length () <= 1 && dbg_cnt (devirt))
{
cgraph_node *target, *node = edge->caller;
if (targets.length () == 1)
target = targets[0];
else
- target = cgraph_get_create_node
+ target = cgraph_node::get_create
(builtin_decl_implicit (BUILT_IN_UNREACHABLE));
- if (dump_file)
- fprintf (dump_file,
- "Devirtualizing call in %s/%i to %s/%i\n",
- edge->caller->name (),
- edge->caller->order,
- target->name (), target->order);
- edge = cgraph_make_edge_direct (edge, target);
- if (inline_summary_vec)
- inline_update_overall_summary (node);
+ if (dump_enabled_p ())
+ {
+ dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, edge->call_stmt,
+ "devirtualizing call in %s to %s\n",
+ edge->caller->dump_name (),
+ target->dump_name ());
+ }
+ edge = edge->make_direct (target);
+ if (ipa_fn_summaries)
+ ipa_update_overall_fn_summary (node);
else if (edge->call_stmt)
- cgraph_redirect_edge_call_stmt_to_callee (edge);
+ edge->redirect_call_stmt_to_callee ();
}
}
}
After inlining we release their bodies and turn them into unanalyzed
nodes even when they are reachable.
- BEFORE_INLINING_P specify whether we are before or after inlining.
-
- virtual functions are kept in callgraph even if they seem unreachable in
hope calls to them will be devirtualized.
we set AUX pointer of processed symbols in the boundary to constant 2. */
bool
-symtab_remove_unreachable_nodes (bool before_inlining_p, FILE *file)
+symbol_table::remove_unreachable_nodes (FILE *file)
{
symtab_node *first = (symtab_node *) (void *) 1;
struct cgraph_node *node, *next;
varpool_node *vnode, *vnext;
bool changed = false;
- struct pointer_set_t *reachable = pointer_set_create ();
- struct pointer_set_t *body_needed_for_clonning = pointer_set_create ();
- struct pointer_set_t *reachable_call_targets = pointer_set_create ();
+ hash_set<symtab_node *> reachable;
+ hash_set<tree> body_needed_for_clonning;
+ hash_set<void *> reachable_call_targets;
timevar_push (TV_IPA_UNREACHABLE);
-#ifdef ENABLE_CHECKING
- verify_symtab ();
-#endif
- if (optimize && flag_devirtualize)
- build_type_inheritance_graph ();
+ build_type_inheritance_graph ();
if (file)
fprintf (file, "\nReclaiming functions:");
-#ifdef ENABLE_CHECKING
- FOR_EACH_FUNCTION (node)
- gcc_assert (!node->aux);
- FOR_EACH_VARIABLE (vnode)
- gcc_assert (!vnode->aux);
-#endif
+ if (flag_checking)
+ {
+ FOR_EACH_FUNCTION (node)
+ gcc_assert (!node->aux);
+ FOR_EACH_VARIABLE (vnode)
+ gcc_assert (!vnode->aux);
+ }
/* Mark functions whose bodies are obviously needed.
This is mostly when they can be referenced externally. Inline clones
are special since their declarations are shared with master clone and thus
FOR_EACH_FUNCTION (node)
{
node->used_as_abstract_origin = false;
+ node->indirect_call_target = false;
if (node->definition
&& !node->global.inlined_to
&& !node->in_other_partition
- && !cgraph_can_remove_if_no_direct_calls_and_refs_p (node))
+ && !node->can_remove_if_no_direct_calls_and_refs_p ())
{
gcc_assert (!node->global.inlined_to);
- pointer_set_insert (reachable, node);
- enqueue_node (node, &first, reachable);
+ reachable.add (node);
+ enqueue_node (node, &first, &reachable);
}
else
gcc_assert (!node->aux);
/* Mark variables that are obviously needed. */
FOR_EACH_DEFINED_VARIABLE (vnode)
- if (!varpool_can_remove_if_no_refs (vnode)
+ if (!vnode->can_remove_if_no_refs_p()
&& !vnode->in_other_partition)
{
- pointer_set_insert (reachable, vnode);
- enqueue_node (vnode, &first, reachable);
+ reachable.add (vnode);
+ enqueue_node (vnode, &first, &reachable);
}
/* Perform reachability analysis. */
while (first != (symtab_node *) (void *) 1)
{
- bool in_boundary_p = !pointer_set_contains (reachable, first);
+ bool in_boundary_p = !reachable.contains (first);
symtab_node *node = first;
first = (symtab_node *)first->aux;
/* If we are processing symbol in boundary, mark its AUX pointer for
possible later re-processing in enqueue_node. */
if (in_boundary_p)
- node->aux = (void *)2;
+ {
+ node->aux = (void *)2;
+ if (node->alias && node->analyzed)
+ enqueue_node (node->get_alias_target (), &first, &reachable);
+ }
else
{
if (TREE_CODE (node->decl) == FUNCTION_DECL
&& DECL_ABSTRACT_ORIGIN (node->decl))
{
struct cgraph_node *origin_node
- = cgraph_get_create_node (DECL_ABSTRACT_ORIGIN (node->decl));
- origin_node->used_as_abstract_origin = true;
- enqueue_node (origin_node, &first, reachable);
+ = cgraph_node::get (DECL_ABSTRACT_ORIGIN (node->decl));
+ if (origin_node && !origin_node->used_as_abstract_origin)
+ {
+ origin_node->used_as_abstract_origin = true;
+ gcc_assert (!origin_node->prev_sibling_clone);
+ gcc_assert (!origin_node->next_sibling_clone);
+ for (cgraph_node *n = origin_node->clones; n;
+ n = n->next_sibling_clone)
+ if (n->decl == DECL_ABSTRACT_ORIGIN (node->decl))
+ n->used_as_abstract_origin = true;
+ }
}
/* If any symbol in a comdat group is reachable, force
all externally visible symbols in the same comdat
for (next = node->same_comdat_group;
next != node;
next = next->same_comdat_group)
- if (!symtab_comdat_local_p (next)
- && !pointer_set_insert (reachable, next))
- enqueue_node (next, &first, reachable);
+ if (!next->comdat_local_p ()
+ && !reachable.add (next))
+ enqueue_node (next, &first, &reachable);
}
/* Mark references as reachable. */
- process_references (&node->ref_list, &first,
- before_inlining_p, reachable);
+ process_references (node, &first, &reachable);
}
- if (cgraph_node *cnode = dyn_cast <cgraph_node> (node))
+ if (cgraph_node *cnode = dyn_cast <cgraph_node *> (node))
{
/* Mark the callees reachable unless they are direct calls to extern
inline functions we decided to not inline. */
{
struct cgraph_edge *e;
/* Keep alive possible targets for devirtualization. */
- if (optimize && flag_devirtualize)
+ if (opt_for_fn (cnode->decl, optimize)
+ && opt_for_fn (cnode->decl, flag_devirtualize))
{
struct cgraph_edge *next;
for (e = cnode->indirect_calls; e; e = next)
{
next = e->next_callee;
if (e->indirect_info->polymorphic)
- walk_polymorphic_call_targets (reachable_call_targets,
- e, &first, reachable,
- before_inlining_p);
+ walk_polymorphic_call_targets (&reachable_call_targets,
+ e, &first, &reachable);
}
}
for (e = cnode->callees; e; e = e->next_callee)
{
+ symtab_node *body = e->callee->function_symbol ();
if (e->callee->definition
&& !e->callee->in_other_partition
&& (!e->inline_failed
|| !DECL_EXTERNAL (e->callee->decl)
|| e->callee->alias
- || before_inlining_p))
- pointer_set_insert (reachable, e->callee);
- enqueue_node (e->callee, &first, reachable);
+ || possible_inline_candidate_p (e->callee)))
+ {
+ /* Be sure that we will not optimize out alias target
+ body. */
+ if (DECL_EXTERNAL (e->callee->decl)
+ && e->callee->alias
+ && symtab->state < IPA_SSA_AFTER_INLINING)
+ reachable.add (body);
+ reachable.add (e->callee);
+ }
+ enqueue_node (e->callee, &first, &reachable);
}
/* When inline clone exists, mark body to be preserved so when removing
offline copy of the function we don't kill it. */
if (cnode->global.inlined_to)
- pointer_set_insert (body_needed_for_clonning, cnode->decl);
+ body_needed_for_clonning.add (cnode->decl);
/* For non-inline clones, force their origins to the boundary and ensure
that body is not removed. */
cnode = cnode->clone_of;
if (noninline)
{
- pointer_set_insert (body_needed_for_clonning, cnode->decl);
- enqueue_node (cnode, &first, reachable);
+ body_needed_for_clonning.add (cnode->decl);
+ enqueue_node (cnode, &first, &reachable);
}
}
}
+ else if (cnode->thunk.thunk_p)
+ enqueue_node (cnode->callees->callee, &first, &reachable);
+
/* If any reachable function has simd clones, mark them as
reachable as well. */
if (cnode->simd_clones)
next;
next = next->simdclone->next_clone)
if (in_boundary_p
- || !pointer_set_insert (reachable, next))
- enqueue_node (next, &first, reachable);
+ || !reachable.add (next))
+ enqueue_node (next, &first, &reachable);
}
}
/* When we see constructor of external variable, keep referred nodes in the
boundary. This will also hold initializers of the external vars NODE
refers to. */
- varpool_node *vnode = dyn_cast <varpool_node> (node);
+ varpool_node *vnode = dyn_cast <varpool_node *> (node);
if (vnode
&& DECL_EXTERNAL (node->decl)
&& !vnode->alias
&& in_boundary_p)
{
- struct ipa_ref *ref;
- for (int i = 0; ipa_ref_list_reference_iterate (&node->ref_list, i, ref); i++)
- enqueue_node (ref->referred, &first, reachable);
+ struct ipa_ref *ref = NULL;
+ for (int i = 0; node->iterate_reference (i, ref); i++)
+ enqueue_node (ref->referred, &first, &reachable);
}
}
/* Remove unreachable functions. */
- for (node = cgraph_first_function (); node; node = next)
+ for (node = first_function (); node; node = next)
{
- next = cgraph_next_function (node);
+ next = next_function (node);
/* If node is not needed at all, remove it. */
if (!node->aux)
{
if (file)
- fprintf (file, " %s", node->name ());
- cgraph_remove_node (node);
+ fprintf (file, " %s", node->dump_name ());
+ node->remove ();
changed = true;
}
/* If node is unreachable, remove its body. */
- else if (!pointer_set_contains (reachable, node))
+ else if (!reachable.contains (node))
{
- if (!pointer_set_contains (body_needed_for_clonning, node->decl))
- cgraph_release_function_body (node);
+ /* We keep definitions of thunks and aliases in the boundary so
+ we can walk to the ultimate alias targets and function symbols
+ reliably. */
+ if (node->alias || node->thunk.thunk_p)
+ ;
+ else if (!body_needed_for_clonning.contains (node->decl)
+ && !node->alias && !node->thunk.thunk_p)
+ node->release_body ();
else if (!node->clone_of)
gcc_assert (in_lto_p || DECL_RESULT (node->decl));
- if (node->definition)
+ if (node->definition && !node->alias && !node->thunk.thunk_p)
{
if (file)
- fprintf (file, " %s", node->name ());
+ fprintf (file, " %s", node->dump_name ());
node->body_removed = true;
node->analyzed = false;
node->definition = false;
node->cpp_implicit_alias = false;
node->alias = false;
+ node->transparent_alias = false;
node->thunk.thunk_p = false;
node->weakref = false;
+ /* After early inlining we drop always_inline attributes on
+ bodies of functions that are still referenced (have their
+ address taken). */
+ DECL_ATTRIBUTES (node->decl)
+ = remove_attribute ("always_inline",
+ DECL_ATTRIBUTES (node->decl));
if (!node->in_other_partition)
node->local.local = false;
- cgraph_node_remove_callees (node);
- ipa_remove_all_references (&node->ref_list);
+ node->remove_callees ();
+ node->remove_all_references ();
changed = true;
+ if (node->thunk.thunk_p
+ && node->thunk.add_pointer_bounds_args)
+ {
+ node->thunk.thunk_p = false;
+ node->thunk.add_pointer_bounds_args = false;
+ }
}
}
else
- gcc_assert (node->clone_of || !cgraph_function_with_gimple_body_p (node)
+ gcc_assert (node->clone_of || !node->has_gimple_body_p ()
|| in_lto_p || DECL_RESULT (node->decl));
}
/* Remove unreachable variables. */
if (file)
fprintf (file, "\nReclaiming variables:");
- for (vnode = varpool_first_variable (); vnode; vnode = vnext)
+ for (vnode = first_variable (); vnode; vnode = vnext)
{
- vnext = varpool_next_variable (vnode);
+ vnext = next_variable (vnode);
if (!vnode->aux
/* For can_refer_decl_in_current_unit_p we want to track for
all external variables if they are defined in other partition
or not. */
&& (!flag_ltrans || !DECL_EXTERNAL (vnode->decl)))
{
+ struct ipa_ref *ref = NULL;
+
+ /* First remove the aliases, so varpool::remove can possibly lookup
+ the constructor and save it for future use. */
+ while (vnode->iterate_direct_aliases (0, ref))
+ {
+ if (file)
+ fprintf (file, " %s", ref->referred->dump_name ());
+ ref->referring->remove ();
+ }
if (file)
- fprintf (file, " %s", vnode->name ());
- varpool_remove_node (vnode);
+ fprintf (file, " %s", vnode->dump_name ());
+ vnext = next_variable (vnode);
+ /* Signal removal to the debug machinery. */
+ if (! flag_wpa || flag_incremental_link == INCREMENTAL_LINK_LTO)
+ {
+ vnode->definition = false;
+ (*debug_hooks->late_global_decl) (vnode->decl);
+ }
+ vnode->remove ();
changed = true;
}
- else if (!pointer_set_contains (reachable, vnode))
+ else if (!reachable.contains (vnode) && !vnode->alias)
{
tree init;
if (vnode->definition)
fprintf (file, " %s", vnode->name ());
changed = true;
}
+ /* Keep body if it may be useful for constant folding. */
+ if ((flag_wpa || flag_incremental_link == INCREMENTAL_LINK_LTO)
+ || ((init = ctor_for_folding (vnode->decl)) == error_mark_node))
+ vnode->remove_initializer ();
+ else
+ DECL_INITIAL (vnode->decl) = init;
vnode->body_removed = true;
vnode->definition = false;
vnode->analyzed = false;
vnode->aux = NULL;
- /* Keep body if it may be useful for constant folding. */
- if ((init = ctor_for_folding (vnode->decl)) == error_mark_node)
- varpool_remove_initializer (vnode);
- else
- DECL_INITIAL (vnode->decl) = init;
- ipa_remove_all_references (&vnode->ref_list);
+ vnode->remove_from_same_comdat_group ();
+
+ vnode->remove_all_references ();
}
else
vnode->aux = NULL;
}
- pointer_set_destroy (reachable);
- pointer_set_destroy (body_needed_for_clonning);
- pointer_set_destroy (reachable_call_targets);
-
/* Now update address_taken flags and try to promote functions to be local. */
if (file)
fprintf (file, "\nClearing address taken flags:");
if (node->address_taken
&& !node->used_from_other_partition)
{
- if (!cgraph_for_node_and_aliases (node, has_addr_references_p, NULL, true))
+ if (!node->call_for_symbol_and_aliases
+ (has_addr_references_p, NULL, true))
{
if (file)
fprintf (file, " %s", node->name ());
node->address_taken = false;
changed = true;
- if (cgraph_local_node_p (node))
+ if (node->local_p ()
+ /* Virtual functions may be kept in cgraph just because
+ of possible later devirtualization. Do not mark them as
+ local too early so we won't optimize them out before
+ we are done with polymorphic call analysis. */
+ && (symtab->state >= IPA_SSA_AFTER_INLINING
+ || !node->call_for_symbol_and_aliases
+ (is_indirect_call_target_p, NULL, true)))
{
node->local.local = true;
if (file)
if (file)
fprintf (file, "\n");
-#ifdef ENABLE_CHECKING
- verify_symtab ();
-#endif
+ symtab_node::checking_verify_symtab_nodes ();
/* If we removed something, perhaps profile could be improved. */
- if (changed && optimize && inline_edge_summary_vec.exists ())
+ if (changed && (optimize || in_lto_p) && ipa_call_summaries)
FOR_EACH_DEFINED_FUNCTION (node)
ipa_propagate_frequency (node);
return changed;
}
-/* Discover variables that have no longer address taken or that are read only
- and update their flags.
-
- FIXME: This can not be done in between gimplify and omp_expand since
- readonly flag plays role on what is shared and what is not. Currently we do
- this transformation as part of whole program visibility and re-do at
- ipa-reference pass (to take into account clonning), but it would
- make sense to do it before early optimizations. */
+/* Process references to VNODE and set flags WRITTEN, ADDRESS_TAKEN, READ
+ as needed, also clear EXPLICIT_REFS if the references to given variable
+ do not need to be explicit. */
void
-ipa_discover_readonly_nonaddressable_vars (void)
-{
- varpool_node *vnode;
- if (dump_file)
- fprintf (dump_file, "Clearing variable flags:");
- FOR_EACH_VARIABLE (vnode)
- if (vnode->definition && varpool_all_refs_explicit_p (vnode)
- && (TREE_ADDRESSABLE (vnode->decl)
- || !TREE_READONLY (vnode->decl)))
- {
- bool written = false;
- bool address_taken = false;
- int i;
- struct ipa_ref *ref;
- for (i = 0; ipa_ref_list_referring_iterate (&vnode->ref_list,
- i, ref)
- && (!written || !address_taken); i++)
- switch (ref->use)
- {
- case IPA_REF_ADDR:
- address_taken = true;
- break;
- case IPA_REF_LOAD:
- break;
- case IPA_REF_STORE:
- written = true;
- break;
- }
- if (TREE_ADDRESSABLE (vnode->decl) && !address_taken)
- {
- if (dump_file)
- fprintf (dump_file, " %s (addressable)", vnode->name ());
- TREE_ADDRESSABLE (vnode->decl) = 0;
- }
- if (!TREE_READONLY (vnode->decl) && !address_taken && !written
- /* Making variable in explicit section readonly can cause section
- type conflict.
- See e.g. gcc.c-torture/compile/pr23237.c */
- && DECL_SECTION_NAME (vnode->decl) == NULL)
- {
- if (dump_file)
- fprintf (dump_file, " %s (read-only)", vnode->name ());
- TREE_READONLY (vnode->decl) = 1;
- }
- }
- if (dump_file)
- fprintf (dump_file, "\n");
-}
-
-/* Return true when there is a reference to node and it is not vtable. */
-static bool
-address_taken_from_non_vtable_p (symtab_node *node)
+process_references (varpool_node *vnode,
+ bool *written, bool *address_taken,
+ bool *read, bool *explicit_refs)
{
int i;
struct ipa_ref *ref;
- for (i = 0; ipa_ref_list_referring_iterate (&node->ref_list,
- i, ref); i++)
- if (ref->use == IPA_REF_ADDR)
- {
- varpool_node *node;
- if (is_a <cgraph_node> (ref->referring))
- return true;
- node = ipa_ref_referring_varpool_node (ref);
- if (!DECL_VIRTUAL_P (node->decl))
- return true;
- }
- return false;
-}
-
-/* A helper for comdat_can_be_unshared_p. */
-
-static bool
-comdat_can_be_unshared_p_1 (symtab_node *node)
-{
- /* When address is taken, we don't know if equality comparison won't
- break eventually. Exception are virutal functions, C++
- constructors/destructors and vtables, where this is not possible by
- language standard. */
- if (!DECL_VIRTUAL_P (node->decl)
- && (TREE_CODE (node->decl) != FUNCTION_DECL
- || (!DECL_CXX_CONSTRUCTOR_P (node->decl)
- && !DECL_CXX_DESTRUCTOR_P (node->decl)))
- && address_taken_from_non_vtable_p (node))
- return false;
-
- /* If the symbol is used in some weird way, better to not touch it. */
- if (node->force_output)
- return false;
-
- /* Explicit instantiations needs to be output when possibly
- used externally. */
- if (node->forced_by_abi
- && TREE_PUBLIC (node->decl)
- && (node->resolution != LDPR_PREVAILING_DEF_IRONLY
- && !flag_whole_program))
- return false;
-
- /* Non-readonly and volatile variables can not be duplicated. */
- if (is_a <varpool_node> (node)
- && (!TREE_READONLY (node->decl)
- || TREE_THIS_VOLATILE (node->decl)))
- return false;
- return true;
-}
-
-/* COMDAT functions must be shared only if they have address taken,
- otherwise we can produce our own private implementation with
- -fwhole-program.
- Return true when turning COMDAT functoin static can not lead to wrong
- code when the resulting object links with a library defining same COMDAT.
-
- Virtual functions do have their addresses taken from the vtables,
- but in C++ there is no way to compare their addresses for equality. */
-
-static bool
-comdat_can_be_unshared_p (symtab_node *node)
-{
- if (!comdat_can_be_unshared_p_1 (node))
- return false;
- if (node->same_comdat_group)
- {
- symtab_node *next;
-
- /* If more than one function is in the same COMDAT group, it must
- be shared even if just one function in the comdat group has
- address taken. */
- for (next = node->same_comdat_group;
- next != node; next = next->same_comdat_group)
- if (!comdat_can_be_unshared_p_1 (next))
- return false;
- }
- return true;
-}
-/* Return true when function NODE should be considered externally visible. */
+ if (!vnode->all_refs_explicit_p ()
+ || TREE_THIS_VOLATILE (vnode->decl))
+ *explicit_refs = false;
-static bool
-cgraph_externally_visible_p (struct cgraph_node *node,
- bool whole_program)
-{
- if (!node->definition)
- return false;
- if (!TREE_PUBLIC (node->decl)
- || DECL_EXTERNAL (node->decl))
- return false;
-
- /* Do not try to localize built-in functions yet. One of problems is that we
- end up mangling their asm for WHOPR that makes it impossible to call them
- using the implicit built-in declarations anymore. Similarly this enables
- us to remove them as unreachable before actual calls may appear during
- expansion or folding. */
- if (DECL_BUILT_IN (node->decl))
- return true;
-
- /* If linker counts on us, we must preserve the function. */
- if (symtab_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;
- if (TARGET_DLLIMPORT_DECL_ATTRIBUTES
- && lookup_attribute ("dllexport",
- DECL_ATTRIBUTES (node->decl)))
- return true;
- if (node->resolution == LDPR_PREVAILING_DEF_IRONLY)
- return false;
- /* When doing LTO or whole program, we can bring COMDAT functoins static.
- This improves code quality and we know we will duplicate them at most twice
- (in the case that we are not using plugin and link with object file
- implementing same COMDAT) */
- if ((in_lto_p || whole_program)
- && DECL_COMDAT (node->decl)
- && comdat_can_be_unshared_p (node))
- return false;
-
- /* When doing link time optimizations, hidden symbols become local. */
- 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->definition)
- ;
- else if (!whole_program)
- return true;
-
- if (MAIN_NAME_P (DECL_NAME (node->decl)))
- return true;
-
- return false;
+ for (i = 0; vnode->iterate_referring (i, ref)
+ && *explicit_refs && (!*written || !*address_taken || !*read); i++)
+ switch (ref->use)
+ {
+ case IPA_REF_ADDR:
+ *address_taken = true;
+ break;
+ case IPA_REF_LOAD:
+ *read = true;
+ break;
+ case IPA_REF_STORE:
+ *written = true;
+ break;
+ case IPA_REF_ALIAS:
+ process_references (dyn_cast<varpool_node *> (ref->referring), written,
+ address_taken, read, explicit_refs);
+ break;
+ }
}
-/* Return true when variable VNODE should be considered externally visible. */
+/* Set TREE_READONLY bit. */
bool
-varpool_externally_visible_p (varpool_node *vnode)
+set_readonly_bit (varpool_node *vnode, void *data ATTRIBUTE_UNUSED)
{
- if (DECL_EXTERNAL (vnode->decl))
- return true;
-
- if (!TREE_PUBLIC (vnode->decl))
- return false;
-
- /* If linker counts on us, we must preserve the function. */
- if (symtab_used_from_object_file_p (vnode))
- return true;
-
- if (DECL_HARD_REGISTER (vnode->decl))
- return true;
- if (DECL_PRESERVE_P (vnode->decl))
- return true;
- if (lookup_attribute ("externally_visible",
- DECL_ATTRIBUTES (vnode->decl)))
- return true;
- if (TARGET_DLLIMPORT_DECL_ATTRIBUTES
- && lookup_attribute ("dllexport",
- 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 (symtab_used_from_object_file_p (vnode))
- return true;
- if (vnode->resolution == LDPR_PREVAILING_DEF_IRONLY)
- return false;
-
- /* As a special case, the COMDAT virtual tables can be unshared.
- In LTO mode turn vtables into static variables. The variable is readonly,
- so this does not enable more optimization, but referring static var
- is faster for dynamic linking. Also this match logic hidding vtables
- from LTO symbol tables. */
- if ((in_lto_p || flag_whole_program)
- && DECL_COMDAT (vnode->decl)
- && comdat_can_be_unshared_p (vnode))
- return false;
-
- /* 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->definition)
- ;
- 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;
+ TREE_READONLY (vnode->decl) = true;
return false;
}
-/* Return true if reference to NODE can be replaced by a local alias.
- Local aliases save dynamic linking overhead and enable more optimizations.
- */
+/* Set writeonly bit and clear the initalizer, since it will not be needed. */
bool
-can_replace_by_local_alias (symtab_node *node)
-{
- return (symtab_node_availability (node) > AVAIL_OVERWRITABLE
- && !symtab_can_be_discarded (node));
-}
-
-/* Mark visibility of all functions.
-
- A local function is one whose calls can occur only in the current
- compilation unit and all its calls are explicit, so we can change
- its calling convention. We simply mark all static functions whose
- address is not taken as local.
-
- We also change the TREE_PUBLIC flag of all declarations that are public
- in language point of view but we want to overwrite this default
- via visibilities for the backend point of view. */
-
-static unsigned int
-function_and_variable_visibility (bool whole_program)
+set_writeonly_bit (varpool_node *vnode, void *data)
{
- struct cgraph_node *node;
- varpool_node *vnode;
-
- /* All aliases should be procssed at this point. */
- gcc_checking_assert (!alias_pairs || !alias_pairs->length ());
-
- FOR_EACH_FUNCTION (node)
- {
- int flags = flags_from_decl_or_type (node->decl);
-
- /* Optimize away PURE and CONST constructors and destructors. */
- if (optimize
- && (flags & (ECF_CONST | ECF_PURE))
- && !(flags & ECF_LOOPING_CONST_OR_PURE))
- {
- DECL_STATIC_CONSTRUCTOR (node->decl) = 0;
- DECL_STATIC_DESTRUCTOR (node->decl) = 0;
- }
-
- /* Frontends and alias code marks nodes as needed before parsing is finished.
- We may end up marking as node external nodes where this flag is meaningless
- strip it. */
- if (DECL_EXTERNAL (node->decl) || !node->definition)
- {
- node->force_output = 0;
- node->forced_by_abi = 0;
- }
-
- /* C++ FE on lack of COMDAT support create local COMDAT functions
- (that ought to be shared but can not due to object format
- limitations). It is necessary to keep the flag to make rest of C++ FE
- happy. Clear the flag here to avoid confusion in middle-end. */
- if (DECL_COMDAT (node->decl) && !TREE_PUBLIC (node->decl))
- DECL_COMDAT (node->decl) = 0;
-
- /* For external decls stop tracking same_comdat_group. It doesn't matter
- what comdat group they are in when they won't be emitted in this TU. */
- if (node->same_comdat_group && DECL_EXTERNAL (node->decl))
- {
-#ifdef ENABLE_CHECKING
- symtab_node *n;
-
- for (n = node->same_comdat_group;
- n != node;
- n = n->same_comdat_group)
- /* If at least one of same comdat group functions is external,
- all of them have to be, otherwise it is a front-end bug. */
- gcc_assert (DECL_EXTERNAL (n->decl));
-#endif
- symtab_dissolve_same_comdat_group_list (node);
- }
- gcc_assert ((!DECL_WEAK (node->decl)
- && !DECL_COMDAT (node->decl))
- || TREE_PUBLIC (node->decl)
- || node->weakref
- || DECL_EXTERNAL (node->decl));
- if (cgraph_externally_visible_p (node, whole_program))
- {
- gcc_assert (!node->global.inlined_to);
- node->externally_visible = true;
- }
- else
- {
- node->externally_visible = false;
- node->forced_by_abi = false;
- }
- if (!node->externally_visible
- && node->definition && !node->weakref
- && !DECL_EXTERNAL (node->decl))
- {
- gcc_assert (whole_program || in_lto_p
- || !TREE_PUBLIC (node->decl));
- node->unique_name = ((node->resolution == LDPR_PREVAILING_DEF_IRONLY
- || node->unique_name
- || node->resolution == LDPR_PREVAILING_DEF_IRONLY_EXP)
- && TREE_PUBLIC (node->decl));
- node->resolution = LDPR_PREVAILING_DEF_IRONLY;
- if (node->same_comdat_group && TREE_PUBLIC (node->decl))
- {
- symtab_node *next = node;
-
- /* Set all members of comdat group local. */
- if (node->same_comdat_group)
- for (next = node->same_comdat_group;
- next != node;
- next = next->same_comdat_group)
- {
- symtab_make_decl_local (next->decl);
- next->unique_name = ((next->resolution == LDPR_PREVAILING_DEF_IRONLY
- || next->unique_name
- || next->resolution == LDPR_PREVAILING_DEF_IRONLY_EXP)
- && TREE_PUBLIC (next->decl));
- }
- /* cgraph_externally_visible_p has already checked all other nodes
- in the group and they will all be made local. We need to
- dissolve the group at once so that the predicate does not
- segfault though. */
- symtab_dissolve_same_comdat_group_list (node);
- }
- symtab_make_decl_local (node->decl);
- }
-
- if (node->thunk.thunk_p
- && TREE_PUBLIC (node->decl))
- {
- struct cgraph_node *decl_node = node;
-
- decl_node = cgraph_function_node (decl_node->callees->callee, NULL);
-
- /* Thunks have the same visibility as function they are attached to.
- Make sure the C++ front end set this up properly. */
- if (DECL_ONE_ONLY (decl_node->decl))
- {
- gcc_checking_assert (DECL_COMDAT (node->decl)
- == DECL_COMDAT (decl_node->decl));
- gcc_checking_assert (DECL_COMDAT_GROUP (node->decl)
- == DECL_COMDAT_GROUP (decl_node->decl));
- gcc_checking_assert (node->same_comdat_group);
- }
- if (DECL_EXTERNAL (decl_node->decl))
- DECL_EXTERNAL (node->decl) = 1;
- }
-
- /* If whole comdat group is used only within LTO code, we can dissolve it,
- we handle the unification ourselves.
- We keep COMDAT and weak so visibility out of DSO does not change.
- Later we may bring the symbols static if they are not exported. */
- if (DECL_ONE_ONLY (node->decl)
- && (node->resolution == LDPR_PREVAILING_DEF_IRONLY
- || node->resolution == LDPR_PREVAILING_DEF_IRONLY_EXP))
- {
- symtab_node *next = node;
-
- if (node->same_comdat_group)
- for (next = node->same_comdat_group;
- next != node;
- next = next->same_comdat_group)
- if (next->externally_visible
- && (next->resolution != LDPR_PREVAILING_DEF_IRONLY
- && next->resolution != LDPR_PREVAILING_DEF_IRONLY_EXP))
- break;
- if (node == next)
- {
- if (node->same_comdat_group)
- for (next = node->same_comdat_group;
- next != node;
- next = next->same_comdat_group)
- {
- DECL_COMDAT_GROUP (next->decl) = NULL;
- DECL_WEAK (next->decl) = false;
- }
- DECL_COMDAT_GROUP (node->decl) = NULL;
- symtab_dissolve_same_comdat_group_list (node);
- }
- }
- }
- FOR_EACH_DEFINED_FUNCTION (node)
+ vnode->writeonly = true;
+ if (optimize || in_lto_p)
{
- node->local.local |= cgraph_local_node_p (node);
-
- /* If we know that function can not be overwritten by a different semantics
- and moreover its section can not be discarded, replace all direct calls
- by calls to an nonoverwritable alias. This make dynamic linking
- cheaper and enable more optimization.
-
- TODO: We can also update virtual tables. */
- if (node->callers && can_replace_by_local_alias (node))
- {
- struct cgraph_node *alias = cgraph (symtab_nonoverwritable_alias (node));
-
- if (alias && alias != node)
- {
- while (node->callers)
- {
- struct cgraph_edge *e = node->callers;
-
- cgraph_redirect_edge_callee (e, alias);
- if (gimple_has_body_p (e->caller->decl))
- {
- push_cfun (DECL_STRUCT_FUNCTION (e->caller->decl));
- cgraph_redirect_edge_call_stmt_to_callee (e);
- pop_cfun ();
- }
- }
- }
- }
- }
- FOR_EACH_VARIABLE (vnode)
- {
- /* weak flag makes no sense on local variables. */
- gcc_assert (!DECL_WEAK (vnode->decl)
- || vnode->weakref
- || TREE_PUBLIC (vnode->decl)
- || DECL_EXTERNAL (vnode->decl));
- /* In several cases declarations can not be common:
-
- - when declaration has initializer
- - when it is in weak
- - when it has specific section
- - when it resides in non-generic address space.
- - if declaration is local, it will get into .local common section
- so common flag is not needed. Frontends still produce these in
- certain cases, such as for:
-
- static int a __attribute__ ((common))
-
- Canonicalize things here and clear the redundant flag. */
- if (DECL_COMMON (vnode->decl)
- && (!(TREE_PUBLIC (vnode->decl)
- || DECL_EXTERNAL (vnode->decl))
- || (DECL_INITIAL (vnode->decl)
- && DECL_INITIAL (vnode->decl) != error_mark_node)
- || DECL_WEAK (vnode->decl)
- || DECL_SECTION_NAME (vnode->decl) != NULL
- || ! (ADDR_SPACE_GENERIC_P
- (TYPE_ADDR_SPACE (TREE_TYPE (vnode->decl))))))
- DECL_COMMON (vnode->decl) = 0;
- }
- FOR_EACH_DEFINED_VARIABLE (vnode)
- {
- if (!vnode->definition)
- continue;
- if (varpool_externally_visible_p (vnode))
- vnode->externally_visible = true;
- else
- {
- vnode->externally_visible = false;
- vnode->forced_by_abi = false;
- }
- if (!vnode->externally_visible
- && !vnode->weakref)
+ DECL_INITIAL (vnode->decl) = NULL;
+ if (!vnode->alias)
{
- gcc_assert (in_lto_p || whole_program || !TREE_PUBLIC (vnode->decl));
- vnode->unique_name = ((vnode->resolution == LDPR_PREVAILING_DEF_IRONLY
- || vnode->resolution == LDPR_PREVAILING_DEF_IRONLY_EXP)
- && TREE_PUBLIC (vnode->decl));
- symtab_make_decl_local (vnode->decl);
- if (vnode->same_comdat_group)
- symtab_dissolve_same_comdat_group_list (vnode);
- vnode->resolution = LDPR_PREVAILING_DEF_IRONLY;
+ if (vnode->num_references ())
+ *(bool *)data = true;
+ vnode->remove_all_references ();
}
}
-
- if (dump_file)
- {
- fprintf (dump_file, "\nMarking local functions:");
- FOR_EACH_DEFINED_FUNCTION (node)
- if (node->local.local)
- fprintf (dump_file, " %s", node->name ());
- fprintf (dump_file, "\n\n");
- fprintf (dump_file, "\nMarking externally visible functions:");
- FOR_EACH_DEFINED_FUNCTION (node)
- if (node->externally_visible)
- fprintf (dump_file, " %s", node->name ());
- fprintf (dump_file, "\n\n");
- fprintf (dump_file, "\nMarking externally visible variables:");
- FOR_EACH_DEFINED_VARIABLE (vnode)
- if (vnode->externally_visible)
- fprintf (dump_file, " %s", vnode->name ());
- fprintf (dump_file, "\n\n");
- }
- cgraph_function_flags_ready = true;
- return 0;
-}
-
-/* Local function pass handling visibilities. This happens before LTO streaming
- so in particular -fwhole-program should be ignored at this level. */
-
-static unsigned int
-local_function_and_variable_visibility (void)
-{
- return function_and_variable_visibility (flag_whole_program && !flag_lto);
-}
-
-namespace {
-
-const pass_data pass_data_ipa_function_and_variable_visibility =
-{
- SIMPLE_IPA_PASS, /* type */
- "visibility", /* name */
- OPTGROUP_NONE, /* optinfo_flags */
- false, /* has_gate */
- true, /* has_execute */
- TV_CGRAPHOPT, /* tv_id */
- 0, /* properties_required */
- 0, /* properties_provided */
- 0, /* properties_destroyed */
- 0, /* todo_flags_start */
- ( TODO_remove_functions | TODO_dump_symtab ), /* todo_flags_finish */
-};
-
-class pass_ipa_function_and_variable_visibility : public simple_ipa_opt_pass
-{
-public:
- pass_ipa_function_and_variable_visibility (gcc::context *ctxt)
- : simple_ipa_opt_pass (pass_data_ipa_function_and_variable_visibility,
- ctxt)
- {}
-
- /* opt_pass methods: */
- unsigned int execute () {
- return local_function_and_variable_visibility ();
- }
-
-}; // class pass_ipa_function_and_variable_visibility
-
-} // anon namespace
-
-simple_ipa_opt_pass *
-make_pass_ipa_function_and_variable_visibility (gcc::context *ctxt)
-{
- return new pass_ipa_function_and_variable_visibility (ctxt);
-}
-
-/* Free inline summary. */
-
-static unsigned
-free_inline_summary (void)
-{
- inline_free_summary ();
- return 0;
-}
-
-namespace {
-
-const pass_data pass_data_ipa_free_inline_summary =
-{
- SIMPLE_IPA_PASS, /* type */
- "*free_inline_summary", /* name */
- OPTGROUP_NONE, /* optinfo_flags */
- false, /* has_gate */
- true, /* has_execute */
- TV_IPA_FREE_INLINE_SUMMARY, /* tv_id */
- 0, /* properties_required */
- 0, /* properties_provided */
- 0, /* properties_destroyed */
- 0, /* todo_flags_start */
- 0, /* todo_flags_finish */
-};
-
-class pass_ipa_free_inline_summary : public simple_ipa_opt_pass
-{
-public:
- pass_ipa_free_inline_summary (gcc::context *ctxt)
- : simple_ipa_opt_pass (pass_data_ipa_free_inline_summary, ctxt)
- {}
-
- /* opt_pass methods: */
- unsigned int execute () { return free_inline_summary (); }
-
-}; // class pass_ipa_free_inline_summary
-
-} // anon namespace
-
-simple_ipa_opt_pass *
-make_pass_ipa_free_inline_summary (gcc::context *ctxt)
-{
- return new pass_ipa_free_inline_summary (ctxt);
+ return false;
}
-/* Do not re-run on ltrans stage. */
+/* Clear addressale bit of VNODE. */
-static bool
-gate_whole_program_function_and_variable_visibility (void)
+bool
+clear_addressable_bit (varpool_node *vnode, void *data ATTRIBUTE_UNUSED)
{
- return !flag_ltrans;
+ vnode->address_taken = false;
+ TREE_ADDRESSABLE (vnode->decl) = 0;
+ return false;
}
-/* Bring functionss local at LTO time with -fwhole-program. */
-
-static unsigned int
-whole_program_function_and_variable_visibility (void)
-{
- function_and_variable_visibility (flag_whole_program);
- if (optimize)
- ipa_discover_readonly_nonaddressable_vars ();
- return 0;
-}
+/* Discover variables that have no longer address taken, are read-only or
+ write-only and update their flags.
-namespace {
+ Return true when unreachable symbol removal should be done.
-const pass_data pass_data_ipa_whole_program_visibility =
-{
- IPA_PASS, /* type */
- "whole-program", /* name */
- OPTGROUP_NONE, /* optinfo_flags */
- true, /* has_gate */
- true, /* has_execute */
- TV_CGRAPHOPT, /* tv_id */
- 0, /* properties_required */
- 0, /* properties_provided */
- 0, /* properties_destroyed */
- 0, /* todo_flags_start */
- ( TODO_remove_functions | TODO_dump_symtab ), /* todo_flags_finish */
-};
+ FIXME: This can not be done in between gimplify and omp_expand since
+ readonly flag plays role on what is shared and what is not. Currently we do
+ this transformation as part of whole program visibility and re-do at
+ ipa-reference pass (to take into account clonning), but it would
+ make sense to do it before early optimizations. */
-class pass_ipa_whole_program_visibility : public ipa_opt_pass_d
+bool
+ipa_discover_variable_flags (void)
{
-public:
- pass_ipa_whole_program_visibility (gcc::context *ctxt)
- : ipa_opt_pass_d (pass_data_ipa_whole_program_visibility, ctxt,
- NULL, /* generate_summary */
- NULL, /* write_summary */
- NULL, /* read_summary */
- NULL, /* write_optimization_summary */
- NULL, /* read_optimization_summary */
- NULL, /* stmt_fixup */
- 0, /* function_transform_todo_flags_start */
- NULL, /* function_transform */
- NULL) /* variable_transform */
- {}
-
- /* opt_pass methods: */
- bool gate () {
- return gate_whole_program_function_and_variable_visibility ();
- }
- unsigned int execute () {
- return whole_program_function_and_variable_visibility ();
- }
-
-}; // class pass_ipa_whole_program_visibility
+ if (!flag_ipa_reference_addressable)
+ return false;
-} // anon namespace
+ bool remove_p = false;
+ varpool_node *vnode;
+ if (dump_file)
+ fprintf (dump_file, "Clearing variable flags:");
+ FOR_EACH_VARIABLE (vnode)
+ if (!vnode->alias
+ && (TREE_ADDRESSABLE (vnode->decl)
+ || !vnode->writeonly
+ || !TREE_READONLY (vnode->decl)))
+ {
+ bool written = false;
+ bool address_taken = false;
+ bool read = false;
+ bool explicit_refs = true;
-ipa_opt_pass_d *
-make_pass_ipa_whole_program_visibility (gcc::context *ctxt)
-{
- return new pass_ipa_whole_program_visibility (ctxt);
+ process_references (vnode, &written, &address_taken, &read,
+ &explicit_refs);
+ if (!explicit_refs)
+ continue;
+ if (!address_taken)
+ {
+ if (TREE_ADDRESSABLE (vnode->decl) && dump_file)
+ fprintf (dump_file, " %s (non-addressable)", vnode->name ());
+ vnode->call_for_symbol_and_aliases (clear_addressable_bit, NULL,
+ true);
+ }
+ if (!address_taken && !written
+ /* Making variable in explicit section readonly can cause section
+ type conflict.
+ See e.g. gcc.c-torture/compile/pr23237.c */
+ && vnode->get_section () == NULL)
+ {
+ if (!TREE_READONLY (vnode->decl) && dump_file)
+ fprintf (dump_file, " %s (read-only)", vnode->name ());
+ vnode->call_for_symbol_and_aliases (set_readonly_bit, NULL, true);
+ }
+ if (!vnode->writeonly && !read && !address_taken && written)
+ {
+ if (dump_file)
+ fprintf (dump_file, " %s (write-only)", vnode->name ());
+ vnode->call_for_symbol_and_aliases (set_writeonly_bit, &remove_p,
+ true);
+ }
+ }
+ if (dump_file)
+ fprintf (dump_file, "\n");
+ return remove_p;
}
/* 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.
+ be one of 'I' (for a constructor), 'D' (for a destructor).
+ BODY is a STATEMENT_LIST containing GENERIC
+ statements. PRIORITY is the initialization priority for this
+ constructor or destructor.
FINAL specify whether the externally visible name for collect2 should
be produced. */
TREE_STATIC (decl) = 1;
TREE_USED (decl) = 1;
DECL_ARTIFICIAL (decl) = 1;
+ DECL_IGNORED_P (decl) = 1;
DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (decl) = 1;
DECL_SAVED_TREE (decl) = body;
if (!targetm.have_ctors_dtors && final)
DECL_UNINLINABLE (decl) = 1;
DECL_INITIAL (decl) = make_node (BLOCK);
+ BLOCK_SUPERCONTEXT (DECL_INITIAL (decl)) = decl;
TREE_USED (DECL_INITIAL (decl)) = 1;
DECL_SOURCE_LOCATION (decl) = input_location;
gimplify_function_tree (decl);
- cgraph_add_new_function (decl, false);
+ cgraph_node::add_new_function (decl, false);
set_cfun (NULL);
current_function_decl = NULL;
}
/* 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. */
+ 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)
cgraph_build_static_cdtor_1 (which, body, priority, false);
}
-/* A vector of FUNCTION_DECLs declared as static constructors. */
-static vec<tree> static_ctors;
-/* A vector of FUNCTION_DECLs declared as static destructors. */
-static vec<tree> static_dtors;
-
/* When target does not have ctors and dtors, we call all constructor
and destructor by special initialization/destruction function
recognized by collect2.
destructors and turn them into normal functions. */
static void
-record_cdtor_fn (struct cgraph_node *node)
+record_cdtor_fn (struct cgraph_node *node, vec<tree> *ctors, vec<tree> *dtors)
{
if (DECL_STATIC_CONSTRUCTOR (node->decl))
- static_ctors.safe_push (node->decl);
+ ctors->safe_push (node->decl);
if (DECL_STATIC_DESTRUCTOR (node->decl))
- static_dtors.safe_push (node->decl);
- node = cgraph_get_node (node->decl);
+ dtors->safe_push (node->decl);
+ node = cgraph_node::get (node->decl);
DECL_DISREGARD_INLINE_LIMITS (node->decl) = 1;
}
they are destructors. */
static void
-build_cdtor (bool ctor_p, vec<tree> cdtors)
+build_cdtor (bool ctor_p, const vec<tree> &cdtors)
{
size_t i,j;
size_t len = cdtors.length ();
functions have magic names which are detected by collect2. */
static void
-build_cdtor_fns (void)
+build_cdtor_fns (vec<tree> *ctors, vec<tree> *dtors)
{
- if (!static_ctors.is_empty ())
+ if (!ctors->is_empty ())
{
gcc_assert (!targetm.have_ctors_dtors || in_lto_p);
- static_ctors.qsort (compare_ctor);
- build_cdtor (/*ctor_p=*/true, static_ctors);
+ ctors->qsort (compare_ctor);
+ build_cdtor (/*ctor_p=*/true, *ctors);
}
- if (!static_dtors.is_empty ())
+ if (!dtors->is_empty ())
{
gcc_assert (!targetm.have_ctors_dtors || in_lto_p);
- static_dtors.qsort (compare_dtor);
- build_cdtor (/*ctor_p=*/false, static_dtors);
+ dtors->qsort (compare_dtor);
+ build_cdtor (/*ctor_p=*/false, *dtors);
}
}
static unsigned int
ipa_cdtor_merge (void)
{
+ /* A vector of FUNCTION_DECLs declared as static constructors. */
+ auto_vec<tree, 20> ctors;
+ /* A vector of FUNCTION_DECLs declared as static destructors. */
+ auto_vec<tree, 20> dtors;
struct cgraph_node *node;
FOR_EACH_DEFINED_FUNCTION (node)
if (DECL_STATIC_CONSTRUCTOR (node->decl)
|| DECL_STATIC_DESTRUCTOR (node->decl))
- record_cdtor_fn (node);
- build_cdtor_fns ();
- static_ctors.release ();
- static_dtors.release ();
+ record_cdtor_fn (node, &ctors, &dtors);
+ build_cdtor_fns (&ctors, &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);
-}
-
namespace {
const pass_data pass_data_ipa_cdtor_merge =
IPA_PASS, /* type */
"cdtor", /* name */
OPTGROUP_NONE, /* optinfo_flags */
- true, /* has_gate */
- true, /* has_execute */
TV_CGRAPHOPT, /* tv_id */
0, /* properties_required */
0, /* properties_provided */
{}
/* opt_pass methods: */
- bool gate () { return gate_ipa_cdtor_merge (); }
- unsigned int execute () { return ipa_cdtor_merge (); }
+ virtual bool gate (function *);
+ virtual unsigned int execute (function *) { return ipa_cdtor_merge (); }
}; // class pass_ipa_cdtor_merge
+bool
+pass_ipa_cdtor_merge::gate (function *)
+{
+ /* Perform the pass when we have no ctors/dtors support
+ or at LTO time to merge multiple constructors into single
+ function. */
+ return !targetm.have_ctors_dtors || in_lto_p;
+}
+
} // anon namespace
ipa_opt_pass_d *
{
return new pass_ipa_cdtor_merge (ctxt);
}
+
+/* Invalid pointer representing BOTTOM for single user dataflow. */
+#define BOTTOM ((cgraph_node *)(size_t) 2)
+
+/* Meet operation for single user dataflow.
+ Here we want to associate variables with sigle function that may access it.
+
+ FUNCTION is current single user of a variable, VAR is variable that uses it.
+ Latttice is stored in SINGLE_USER_MAP.
+
+ We represent:
+ - TOP by no entry in SIGNLE_USER_MAP
+ - BOTTOM by BOTTOM in AUX pointer (to save lookups)
+ - known single user by cgraph pointer in SINGLE_USER_MAP. */
+
+cgraph_node *
+meet (cgraph_node *function, varpool_node *var,
+ hash_map<varpool_node *, cgraph_node *> &single_user_map)
+{
+ struct cgraph_node *user, **f;
+
+ if (var->aux == BOTTOM)
+ return BOTTOM;
+
+ f = single_user_map.get (var);
+ if (!f)
+ return function;
+ user = *f;
+ if (!function)
+ return user;
+ else if (function != user)
+ return BOTTOM;
+ else
+ return function;
+}
+
+/* Propagation step of single-use dataflow.
+
+ Check all uses of VNODE and see if they are used by single function FUNCTION.
+ SINGLE_USER_MAP represents the dataflow lattice. */
+
+cgraph_node *
+propagate_single_user (varpool_node *vnode, cgraph_node *function,
+ hash_map<varpool_node *, cgraph_node *> &single_user_map)
+{
+ int i;
+ struct ipa_ref *ref;
+
+ gcc_assert (!vnode->externally_visible);
+
+ /* If node is an alias, first meet with its target. */
+ if (vnode->alias)
+ function = meet (function, vnode->get_alias_target (), single_user_map);
+
+ /* Check all users and see if they correspond to a single function. */
+ for (i = 0; vnode->iterate_referring (i, ref) && function != BOTTOM; i++)
+ {
+ struct cgraph_node *cnode = dyn_cast <cgraph_node *> (ref->referring);
+ if (cnode)
+ {
+ if (cnode->global.inlined_to)
+ cnode = cnode->global.inlined_to;
+ if (!function)
+ function = cnode;
+ else if (function != cnode)
+ function = BOTTOM;
+ }
+ else
+ function = meet (function, dyn_cast <varpool_node *> (ref->referring),
+ single_user_map);
+ }
+ return function;
+}
+
+/* Pass setting used_by_single_function flag.
+ This flag is set on variable when there is only one function that may
+ possibly referr to it. */
+
+static unsigned int
+ipa_single_use (void)
+{
+ varpool_node *first = (varpool_node *) (void *) 1;
+ varpool_node *var;
+ hash_map<varpool_node *, cgraph_node *> single_user_map;
+
+ FOR_EACH_DEFINED_VARIABLE (var)
+ if (!var->all_refs_explicit_p ())
+ var->aux = BOTTOM;
+ else
+ {
+ /* Enqueue symbol for dataflow. */
+ var->aux = first;
+ first = var;
+ }
+
+ /* The actual dataflow. */
+
+ while (first != (void *) 1)
+ {
+ cgraph_node *user, *orig_user, **f;
+
+ var = first;
+ first = (varpool_node *)first->aux;
+
+ f = single_user_map.get (var);
+ if (f)
+ orig_user = *f;
+ else
+ orig_user = NULL;
+ user = propagate_single_user (var, orig_user, single_user_map);
+
+ gcc_checking_assert (var->aux != BOTTOM);
+
+ /* If user differs, enqueue all references. */
+ if (user != orig_user)
+ {
+ unsigned int i;
+ ipa_ref *ref;
+
+ single_user_map.put (var, user);
+
+ /* Enqueue all aliases for re-processing. */
+ for (i = 0; var->iterate_direct_aliases (i, ref); i++)
+ if (!ref->referring->aux)
+ {
+ ref->referring->aux = first;
+ first = dyn_cast <varpool_node *> (ref->referring);
+ }
+ /* Enqueue all users for re-processing. */
+ for (i = 0; var->iterate_reference (i, ref); i++)
+ if (!ref->referred->aux
+ && ref->referred->definition
+ && is_a <varpool_node *> (ref->referred))
+ {
+ ref->referred->aux = first;
+ first = dyn_cast <varpool_node *> (ref->referred);
+ }
+
+ /* If user is BOTTOM, just punt on this var. */
+ if (user == BOTTOM)
+ var->aux = BOTTOM;
+ else
+ var->aux = NULL;
+ }
+ else
+ var->aux = NULL;
+ }
+
+ FOR_EACH_DEFINED_VARIABLE (var)
+ {
+ if (var->aux != BOTTOM)
+ {
+ /* Not having the single user known means that the VAR is
+ unreachable. Either someone forgot to remove unreachable
+ variables or the reachability here is wrong. */
+
+ gcc_checking_assert (single_user_map.get (var));
+
+ if (dump_file)
+ {
+ fprintf (dump_file, "Variable %s is used by single function\n",
+ var->dump_name ());
+ }
+ var->used_by_single_function = true;
+ }
+ var->aux = NULL;
+ }
+ return 0;
+}
+
+namespace {
+
+const pass_data pass_data_ipa_single_use =
+{
+ IPA_PASS, /* type */
+ "single-use", /* name */
+ OPTGROUP_NONE, /* optinfo_flags */
+ TV_CGRAPHOPT, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ 0, /* todo_flags_finish */
+};
+
+class pass_ipa_single_use : public ipa_opt_pass_d
+{
+public:
+ pass_ipa_single_use (gcc::context *ctxt)
+ : ipa_opt_pass_d (pass_data_ipa_single_use, ctxt,
+ NULL, /* generate_summary */
+ NULL, /* write_summary */
+ NULL, /* read_summary */
+ NULL, /* write_optimization_summary */
+ NULL, /* read_optimization_summary */
+ NULL, /* stmt_fixup */
+ 0, /* function_transform_todo_flags_start */
+ NULL, /* function_transform */
+ NULL) /* variable_transform */
+ {}
+
+ /* opt_pass methods: */
+ virtual unsigned int execute (function *) { return ipa_single_use (); }
+
+}; // class pass_ipa_single_use
+
+} // anon namespace
+
+ipa_opt_pass_d *
+make_pass_ipa_single_use (gcc::context *ctxt)
+{
+ return new pass_ipa_single_use (ctxt);
+}
+
+/* Materialize all clones. */
+
+namespace {
+
+const pass_data pass_data_materialize_all_clones =
+{
+ SIMPLE_IPA_PASS, /* type */
+ "materialize-all-clones", /* name */
+ OPTGROUP_NONE, /* optinfo_flags */
+ TV_IPA_OPT, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ 0, /* todo_flags_finish */
+};
+
+class pass_materialize_all_clones : public simple_ipa_opt_pass
+{
+public:
+ pass_materialize_all_clones (gcc::context *ctxt)
+ : simple_ipa_opt_pass (pass_data_materialize_all_clones, ctxt)
+ {}
+
+ /* opt_pass methods: */
+ virtual unsigned int execute (function *)
+ {
+ symtab->materialize_all_clones ();
+ return 0;
+ }
+
+}; // class pass_materialize_all_clones
+
+} // anon namespace
+
+simple_ipa_opt_pass *
+make_pass_materialize_all_clones (gcc::context *ctxt)
+{
+ return new pass_materialize_all_clones (ctxt);
+}
projects / gcc.git / blobdiff