#include "timevar.h"
#include "gimple.h"
#include "ggc.h"
+#include "flags.h"
/* Fill array order with all nodes with output flag set in the reverse
topological order. */
node2->aux = edge->next_caller;
else
node2->aux = &last;
+ /* Break possible cycles involving always-inline
+ functions by ignoring edges from always-inline
+ functions to non-always-inline functions. */
+ if (edge->caller->local.disregard_inline_limits
+ && !edge->callee->local.disregard_inline_limits)
+ continue;
if (!edge->caller->aux)
{
if (!edge->caller->callers)
}
}
+/* Add cgraph NODE to queue starting at FIRST.
+
+ The queue is linked via AUX pointers and terminated by pointer to 1.
+ We enqueue nodes at two occasions: when we find them reachable or when we find
+ their bodies needed for further clonning. In the second case we mark them
+ by pointer to 2 after processing so they are re-queue when they become
+ reachable. */
+
+static void
+enqueue_cgraph_node (struct cgraph_node *node, struct cgraph_node **first)
+{
+ /* 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 && !node->reachable)
+ return;
+ node->aux = *first;
+ *first = node;
+}
+
+/* Add varpool NODE to queue starting at FIRST. */
+
+static void
+enqueue_varpool_node (struct varpool_node *node, struct varpool_node **first)
+{
+ node->aux = *first;
+ *first = node;
+}
+
+/* Process references. */
+
+static void
+process_references (struct ipa_ref_list *list,
+ struct cgraph_node **first,
+ struct varpool_node **first_varpool,
+ bool before_inlining_p)
+{
+ int i;
+ struct ipa_ref *ref;
+ for (i = 0; ipa_ref_list_reference_iterate (list, i, ref); i++)
+ {
+ if (ref->refered_type == IPA_REF_CGRAPH)
+ {
+ struct cgraph_node *node = ipa_ref_node (ref);
+ if (!node->reachable
+ && (!DECL_EXTERNAL (node->decl)
+ || before_inlining_p))
+ {
+ node->reachable = true;
+ enqueue_cgraph_node (node, first);
+ }
+ }
+ else
+ {
+ struct varpool_node *node = ipa_ref_varpool_node (ref);
+ if (!node->needed)
+ {
+ varpool_mark_needed_node (node);
+ enqueue_varpool_node (node, first_varpool);
+ }
+ }
+ }
+}
+
+/* Return true when function NODE can be removed from callgraph
+ if all direct calls are eliminated. */
+
+static inline bool
+varpool_can_remove_if_no_refs (struct varpool_node *node)
+{
+ return (!node->force_output && !node->used_from_other_partition
+ && (DECL_COMDAT (node->decl) || !node->externally_visible));
+}
+
+/* Return true when function can be marked local. */
+
+static bool
+cgraph_local_node_p (struct cgraph_node *node)
+{
+ return (cgraph_only_called_directly_p (node)
+ && node->analyzed
+ && !DECL_EXTERNAL (node->decl)
+ && !node->local.externally_visible
+ && !node->reachable_from_other_partition
+ && !node->in_other_partition);
+}
+
/* Perform reachability analysis and reclaim all unreachable nodes.
If BEFORE_INLINING_P is true this function is called before inlining
decisions has been made. If BEFORE_INLINING_P is false this function also
cgraph_remove_unreachable_nodes (bool before_inlining_p, FILE *file)
{
struct cgraph_node *first = (struct cgraph_node *) (void *) 1;
- struct cgraph_node *processed = (struct cgraph_node *) (void *) 2;
+ struct varpool_node *first_varpool = (struct varpool_node *) (void *) 1;
struct cgraph_node *node, *next;
+ struct varpool_node *vnode, *vnext;
bool changed = false;
#ifdef ENABLE_CHECKING
#ifdef ENABLE_CHECKING
for (node = cgraph_nodes; node; node = node->next)
gcc_assert (!node->aux);
+ for (vnode = varpool_nodes; vnode; vnode = vnode->next)
+ gcc_assert (!vnode->aux);
#endif
+ varpool_reset_queue ();
for (node = cgraph_nodes; node; node = node->next)
- if (!cgraph_can_remove_if_no_direct_calls_p (node)
+ if (!cgraph_can_remove_if_no_direct_calls_and_refs_p (node)
&& ((!DECL_EXTERNAL (node->decl))
- || !node->analyzed
|| before_inlining_p))
{
gcc_assert (!node->global.inlined_to);
- node->aux = first;
- first = node;
+ enqueue_cgraph_node (node, &first);
node->reachable = true;
}
else
gcc_assert (!node->aux);
node->reachable = false;
}
+ for (vnode = varpool_nodes; vnode; vnode = vnode->next)
+ {
+ vnode->next_needed = NULL;
+ vnode->prev_needed = NULL;
+ if (!varpool_can_remove_if_no_refs (vnode))
+ {
+ vnode->needed = false;
+ varpool_mark_needed_node (vnode);
+ enqueue_varpool_node (vnode, &first_varpool);
+ }
+ else
+ vnode->needed = false;
+ }
/* Perform reachability analysis. As a special case do not consider
extern inline functions not inlined as live because we won't output
- them at all. */
- while (first != (void *) 1)
+ them at all.
+
+ We maintain two worklist, one for cgraph nodes other for varpools and
+ are finished once both are empty. */
+
+ while (first != (struct cgraph_node *) (void *) 1
+ || first_varpool != (struct varpool_node *) (void *) 1)
{
- struct cgraph_edge *e;
- node = first;
- first = (struct cgraph_node *) first->aux;
- node->aux = processed;
-
- if (node->reachable)
- for (e = node->callees; e; e = e->next_callee)
- if (!e->callee->reachable
- && node->analyzed
- && (!e->inline_failed || !e->callee->analyzed
- || (!DECL_EXTERNAL (e->callee->decl))
- || before_inlining_p))
+ if (first != (struct cgraph_node *) (void *) 1)
+ {
+ struct cgraph_edge *e;
+ node = first;
+ first = (struct cgraph_node *) first->aux;
+ if (!node->reachable)
+ node->aux = (void *)2;
+
+ /* If we found this node reachable, first mark on the callees
+ reachable too, unless they are direct calls to extern inline functions
+ we decided to not inline. */
+ if (node->reachable)
+ for (e = node->callees; e; e = e->next_callee)
+ if (!e->callee->reachable
+ && node->analyzed
+ && (!e->inline_failed || !e->callee->analyzed
+ || (!DECL_EXTERNAL (e->callee->decl))
+ || before_inlining_p))
+ {
+ e->callee->reachable = true;
+ enqueue_cgraph_node (e->callee, &first);
+ }
+
+ /* If any function in a comdat group is reachable, force
+ all other functions in the same comdat group to be
+ also reachable. */
+ if (node->same_comdat_group
+ && node->reachable
+ && !node->global.inlined_to)
{
- bool prev_reachable = e->callee->reachable;
- e->callee->reachable |= node->reachable;
- if (!e->callee->aux
- || (e->callee->aux == processed
- && prev_reachable != e->callee->reachable))
- {
- e->callee->aux = first;
- first = e->callee;
- }
+ for (next = node->same_comdat_group;
+ next != node;
+ next = next->same_comdat_group)
+ if (!next->reachable)
+ {
+ next->reachable = true;
+ enqueue_cgraph_node (next, &first);
+ }
}
- /* If any function in a comdat group is reachable, force
- all other functions in the same comdat group to be
- also reachable. */
- if (node->same_comdat_group
- && node->reachable
- && !node->global.inlined_to)
- {
- for (next = node->same_comdat_group;
- next != node;
- next = next->same_comdat_group)
- if (!next->reachable)
- {
- next->aux = first;
- first = next;
- next->reachable = true;
- }
- }
-
- /* We can freely remove inline clones even if they are cloned, however if
- function is clone of real clone, we must keep it around in order to
- make materialize_clones produce function body with the changes
- applied. */
- while (node->clone_of && !node->clone_of->aux && !gimple_has_body_p (node->decl))
- {
- bool noninline = node->clone_of->decl != node->decl;
- node = node->clone_of;
- if (noninline)
+ /* We can freely remove inline clones even if they are cloned, however if
+ function is clone of real clone, we must keep it around in order to
+ make materialize_clones produce function body with the changes
+ applied. */
+ while (node->clone_of && !node->clone_of->aux && !gimple_has_body_p (node->decl))
{
- node->aux = first;
- first = node;
- break;
+ bool noninline = node->clone_of->decl != node->decl;
+ node = node->clone_of;
+ if (noninline && !node->reachable && !node->aux)
+ {
+ enqueue_cgraph_node (node, &first);
+ break;
+ }
}
+ process_references (&node->ref_list, &first, &first_varpool, before_inlining_p);
+ }
+ if (first_varpool != (struct varpool_node *) (void *) 1)
+ {
+ vnode = first_varpool;
+ first_varpool = (struct varpool_node *)first_varpool->aux;
+ vnode->aux = NULL;
+ process_references (&vnode->ref_list, &first, &first_varpool, before_inlining_p);
}
}
- /* Remove unreachable nodes. Extern inline functions need special care;
- Unreachable extern inline functions shall be removed.
- Reachable extern inline functions we never inlined shall get their bodies
- eliminated.
- Reachable extern inline functions we sometimes inlined will be turned into
- unanalyzed nodes so they look like for true extern functions to the rest
- of code. Body of such functions is released via remove_node once the
- inline clones are eliminated. */
+ /* Remove unreachable nodes.
+
+ Completely unreachable functions can be fully removed from the callgraph.
+ Extern inline functions that we decided to not inline need to become unanalyzed nodes of
+ callgraph (so we still have edges to them). We remove function body then.
+
+ Also we need to care functions that are unreachable but we need to keep them around
+ for later clonning. In this case we also turn them to unanalyzed nodes, but
+ keep the body around. */
for (node = cgraph_nodes; node; node = next)
{
next = node->next;
/* See if there is reachable caller. */
for (e = node->callers; e; e = e->next_caller)
- if (e->caller->aux)
+ if (e->caller->reachable)
break;
/* If so, we need to keep node in the callgraph. */
}
node->aux = NULL;
}
+
+ if (file)
+ fprintf (file, "\n");
+
+ /* We must release unused extern inlines or sanity checking will fail. Rest of transformations
+ are undesirable at -O0 since we do not want to remove anything. */
+ if (!optimize)
+ return changed;
+
+ if (file)
+ fprintf (file, "Reclaiming variables:");
+ for (vnode = varpool_nodes; vnode; vnode = vnext)
+ {
+ vnext = vnode->next;
+ if (!vnode->needed)
+ {
+ if (file)
+ fprintf (file, " %s", varpool_node_name (vnode));
+ varpool_remove_node (vnode);
+ changed = true;
+ }
+ }
+
+ /* Now update address_taken flags and try to promote functions to be local. */
+
+ if (file)
+ fprintf (file, "\nClearing address taken flags:");
+ for (node = cgraph_nodes; node; node = node->next)
+ if (node->address_taken
+ && !node->reachable_from_other_partition)
+ {
+ int i;
+ struct ipa_ref *ref;
+ bool found = false;
+ for (i = 0; ipa_ref_list_refering_iterate (&node->ref_list, i, ref)
+ && !found; i++)
+ {
+ gcc_assert (ref->use == IPA_REF_ADDR);
+ found = true;
+ }
+ if (!found)
+ {
+ if (file)
+ fprintf (file, " %s", cgraph_node_name (node));
+ node->address_taken = false;
+ changed = true;
+ if (cgraph_local_node_p (node))
+ {
+ node->local.local = true;
+ if (file)
+ fprintf (file, " (local)");
+ }
+ }
+ }
+
#ifdef ENABLE_CHECKING
verify_cgraph ();
#endif
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 ipa-reference pass, but it would make sense
+ to do it before early optimizations. */
+
+void
+ipa_discover_readonly_nonaddressable_vars (void)
+{
+ struct varpool_node *vnode;
+ if (dump_file)
+ fprintf (dump_file, "Clearing variable flags:");
+ for (vnode = varpool_nodes; vnode; vnode = vnode->next)
+ if (vnode->finalized && 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_refering_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)", varpool_node_name (vnode));
+ 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)", varpool_node_name (vnode));
+ TREE_READONLY (vnode->decl) = 1;
+ }
+ }
+ if (dump_file)
+ fprintf (dump_file, "\n");
+}
+
+/* Return true when function NODE should be considered externally visible. */
+
static bool
cgraph_externally_visible_p (struct cgraph_node *node, bool whole_program)
{
return false;
}
+/* Dissolve the same_comdat_group list in which NODE resides. */
+
+static void
+dissolve_same_comdat_group_list (struct cgraph_node *node)
+{
+ struct cgraph_node *n = node, *next;
+ do
+ {
+ next = n->same_comdat_group;
+ n->same_comdat_group = NULL;
+ n = next;
+ }
+ while (n != node);
+}
+
/* Mark visibility of all functions.
A local function is one whose calls can occur only in the current
and simplifies later passes. */
if (node->same_comdat_group && DECL_EXTERNAL (node->decl))
{
- struct cgraph_node *n = node, *next;
- do
- {
+#ifdef ENABLE_CHECKING
+ struct cgraph_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));
- next = n->same_comdat_group;
- n->same_comdat_group = NULL;
- n = next;
- }
- while (n != node);
+#endif
+ dissolve_same_comdat_group_list (node);
}
gcc_assert ((!DECL_WEAK (node->decl) && !DECL_COMDAT (node->decl))
|| TREE_PUBLIC (node->decl) || DECL_EXTERNAL (node->decl));
if (!node->local.externally_visible && node->analyzed
&& !DECL_EXTERNAL (node->decl))
{
+ struct cgraph_node *alias;
gcc_assert (whole_program || !TREE_PUBLIC (node->decl));
cgraph_make_decl_local (node->decl);
+ for (alias = node->same_body; alias; alias = alias->next)
+ cgraph_make_decl_local (alias->decl);
+ if (node->same_comdat_group)
+ /* 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. */
+ dissolve_same_comdat_group_list (node);
}
- node->local.local = (cgraph_only_called_directly_p (node)
- && node->analyzed
- && !DECL_EXTERNAL (node->decl)
- && !node->local.externally_visible);
+ node->local.local = cgraph_local_node_p (node);
}
for (vnode = varpool_nodes; vnode; vnode = vnode->next)
{
0, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
- TODO_remove_functions | TODO_dump_cgraph/* todo_flags_finish */
+ TODO_remove_functions | TODO_dump_cgraph
+ | TODO_ggc_collect /* todo_flags_finish */
}
};
0, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
- TODO_dump_cgraph | TODO_remove_functions/* todo_flags_finish */
+ TODO_remove_functions | TODO_dump_cgraph
+ | TODO_ggc_collect /* todo_flags_finish */
},
NULL, /* generate_summary */
NULL, /* write_summary */
NULL, /* read_summary */
- NULL, /* function_read_summary */
+ NULL, /* write_optimization_summary */
+ NULL, /* read_optimization_summary */
NULL, /* stmt_fixup */
0, /* TODOs */
NULL, /* function_transform */
dump_cgraph_node_set (stderr, set);
}
+/* Hash a varpool node set element. */
+
+static hashval_t
+hash_varpool_node_set_element (const void *p)
+{
+ const_varpool_node_set_element element = (const_varpool_node_set_element) p;
+ return htab_hash_pointer (element->node);
+}
+
+/* Compare two varpool node set elements. */
+
+static int
+eq_varpool_node_set_element (const void *p1, const void *p2)
+{
+ const_varpool_node_set_element e1 = (const_varpool_node_set_element) p1;
+ const_varpool_node_set_element e2 = (const_varpool_node_set_element) p2;
+
+ return e1->node == e2->node;
+}
+
+/* Create a new varpool node set. */
+
+varpool_node_set
+varpool_node_set_new (void)
+{
+ varpool_node_set new_node_set;
+
+ new_node_set = GGC_NEW (struct varpool_node_set_def);
+ new_node_set->hashtab = htab_create_ggc (10,
+ hash_varpool_node_set_element,
+ eq_varpool_node_set_element,
+ NULL);
+ new_node_set->nodes = NULL;
+ return new_node_set;
+}
+
+/* Add varpool_node NODE to varpool_node_set SET. */
+
+void
+varpool_node_set_add (varpool_node_set set, struct varpool_node *node)
+{
+ void **slot;
+ varpool_node_set_element element;
+ struct varpool_node_set_element_def dummy;
+
+ dummy.node = node;
+ slot = htab_find_slot (set->hashtab, &dummy, INSERT);
+
+ if (*slot != HTAB_EMPTY_ENTRY)
+ {
+ element = (varpool_node_set_element) *slot;
+ gcc_assert (node == element->node
+ && (VEC_index (varpool_node_ptr, set->nodes, element->index)
+ == node));
+ return;
+ }
+
+ /* Insert node into hash table. */
+ element =
+ (varpool_node_set_element) GGC_NEW (struct varpool_node_set_element_def);
+ element->node = node;
+ element->index = VEC_length (varpool_node_ptr, set->nodes);
+ *slot = element;
+
+ /* Insert into node vector. */
+ VEC_safe_push (varpool_node_ptr, gc, set->nodes, node);
+}
+
+/* Remove varpool_node NODE from varpool_node_set SET. */
+
+void
+varpool_node_set_remove (varpool_node_set set, struct varpool_node *node)
+{
+ void **slot, **last_slot;
+ varpool_node_set_element element, last_element;
+ struct varpool_node *last_node;
+ struct varpool_node_set_element_def dummy;
+
+ dummy.node = node;
+ slot = htab_find_slot (set->hashtab, &dummy, NO_INSERT);
+ if (slot == NULL)
+ return;
+
+ element = (varpool_node_set_element) *slot;
+ gcc_assert (VEC_index (varpool_node_ptr, set->nodes, element->index)
+ == node);
+
+ /* Remove from vector. We do this by swapping node with the last element
+ of the vector. */
+ last_node = VEC_pop (varpool_node_ptr, set->nodes);
+ if (last_node != node)
+ {
+ dummy.node = last_node;
+ last_slot = htab_find_slot (set->hashtab, &dummy, NO_INSERT);
+ last_element = (varpool_node_set_element) *last_slot;
+ gcc_assert (last_element);
+
+ /* Move the last element to the original spot of NODE. */
+ last_element->index = element->index;
+ VEC_replace (varpool_node_ptr, set->nodes, last_element->index,
+ last_node);
+ }
+
+ /* Remove element from hash table. */
+ htab_clear_slot (set->hashtab, slot);
+ ggc_free (element);
+}
+
+/* Find NODE in SET and return an iterator to it if found. A null iterator
+ is returned if NODE is not in SET. */
+
+varpool_node_set_iterator
+varpool_node_set_find (varpool_node_set set, struct varpool_node *node)
+{
+ void **slot;
+ struct varpool_node_set_element_def dummy;
+ varpool_node_set_element element;
+ varpool_node_set_iterator vsi;
+
+ dummy.node = node;
+ slot = htab_find_slot (set->hashtab, &dummy, NO_INSERT);
+ if (slot == NULL)
+ vsi.index = (unsigned) ~0;
+ else
+ {
+ element = (varpool_node_set_element) *slot;
+ gcc_assert (VEC_index (varpool_node_ptr, set->nodes, element->index)
+ == node);
+ vsi.index = element->index;
+ }
+ vsi.set = set;
+
+ return vsi;
+}
+
+/* Dump content of SET to file F. */
+
+void
+dump_varpool_node_set (FILE *f, varpool_node_set set)
+{
+ varpool_node_set_iterator iter;
+
+ for (iter = vsi_start (set); !vsi_end_p (iter); vsi_next (&iter))
+ {
+ struct varpool_node *node = vsi_node (iter);
+ dump_varpool_node (f, node);
+ }
+}
+
+/* Dump content of SET to stderr. */
+
+void
+debug_varpool_node_set (varpool_node_set set)
+{
+ dump_varpool_node_set (stderr, set);
+}
+
+
+/* Simple ipa profile pass propagating frequencies across the callgraph. */
+
+static unsigned int
+ipa_profile (void)
+{
+ struct cgraph_node **order = XCNEWVEC (struct cgraph_node *, cgraph_n_nodes);
+ struct cgraph_edge *e;
+ int order_pos;
+ bool something_changed = false;
+ int i;
+
+ order_pos = cgraph_postorder (order);
+ for (i = order_pos - 1; i >= 0; i--)
+ {
+ if (order[i]->local.local && cgraph_propagate_frequency (order[i]))
+ {
+ for (e = order[i]->callees; e; e = e->next_callee)
+ if (e->callee->local.local && !e->callee->aux)
+ {
+ something_changed = true;
+ e->callee->aux = (void *)1;
+ }
+ }
+ order[i]->aux = NULL;
+ }
+
+ while (something_changed)
+ {
+ something_changed = false;
+ for (i = order_pos - 1; i >= 0; i--)
+ {
+ if (order[i]->aux && cgraph_propagate_frequency (order[i]))
+ {
+ for (e = order[i]->callees; e; e = e->next_callee)
+ if (e->callee->local.local && !e->callee->aux)
+ {
+ something_changed = true;
+ e->callee->aux = (void *)1;
+ }
+ }
+ order[i]->aux = NULL;
+ }
+ }
+ free (order);
+ return 0;
+}
+
+static bool
+gate_ipa_profile (void)
+{
+ return flag_ipa_profile;
+}
+
+struct ipa_opt_pass_d pass_ipa_profile =
+{
+ {
+ IPA_PASS,
+ "ipa-profile", /* name */
+ gate_ipa_profile, /* gate */
+ ipa_profile, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_IPA_PROFILE, /* 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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