/* Basic IPA optimizations and utilities.
- Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
+ Copyright (C) 2003, 2004, 2005, 2007, 2008 Free Software Foundation,
+ Inc.
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
-Software Foundation; either version 2, or (at your option) any later
+Software Foundation; either version 3, or (at your option) any later
version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
for more details.
You should have received a copy of the GNU General Public License
-along with GCC; see the file COPYING. If not, write to the Free
-Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
-02110-1301, USA. */
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
#include "cgraph.h"
+#include "tree-pass.h"
+#include "timevar.h"
+#include "gimple.h"
+#include "ggc.h"
/* Fill array order with all nodes with output flag set in the reverse
topological order. */
int stack_size = 0;
int order_pos = 0;
struct cgraph_edge *edge, last;
+ int pass;
struct cgraph_node **stack =
XCNEWVEC (struct cgraph_node *, cgraph_n_nodes);
/* We have to deal with cycles nicely, so use a depth first traversal
output algorithm. Ignore the fact that some functions won't need
to be output and put them into order as well, so we get dependencies
- right through intline functions. */
+ right through inline functions. */
for (node = cgraph_nodes; node; node = node->next)
node->aux = NULL;
- for (node = cgraph_nodes; node; node = node->next)
- if (!node->aux)
- {
- node2 = node;
- if (!node->callers)
- node->aux = &last;
- else
- node->aux = node->callers;
- while (node2)
- {
- while (node2->aux != &last)
- {
- edge = node2->aux;
- if (edge->next_caller)
- node2->aux = edge->next_caller;
- else
- node2->aux = &last;
- if (!edge->caller->aux)
- {
- if (!edge->caller->callers)
- edge->caller->aux = &last;
- else
- edge->caller->aux = edge->caller->callers;
- stack[stack_size++] = node2;
- node2 = edge->caller;
- break;
- }
- }
- if (node2->aux == &last)
- {
- order[order_pos++] = node2;
- if (stack_size)
- node2 = stack[--stack_size];
- else
- node2 = NULL;
- }
- }
- }
+ for (pass = 0; pass < 2; pass++)
+ for (node = cgraph_nodes; node; node = node->next)
+ if (!node->aux
+ && (pass
+ || (!cgraph_only_called_directly_p (node)
+ && !node->address_taken)))
+ {
+ node2 = node;
+ if (!node->callers)
+ node->aux = &last;
+ else
+ node->aux = node->callers;
+ while (node2)
+ {
+ while (node2->aux != &last)
+ {
+ edge = (struct cgraph_edge *) node2->aux;
+ if (edge->next_caller)
+ node2->aux = edge->next_caller;
+ else
+ node2->aux = &last;
+ if (!edge->caller->aux)
+ {
+ if (!edge->caller->callers)
+ edge->caller->aux = &last;
+ else
+ edge->caller->aux = edge->caller->callers;
+ stack[stack_size++] = node2;
+ node2 = edge->caller;
+ break;
+ }
+ }
+ if (node2->aux == &last)
+ {
+ order[order_pos++] = node2;
+ if (stack_size)
+ node2 = stack[--stack_size];
+ else
+ node2 = NULL;
+ }
+ }
+ }
free (stack);
for (node = cgraph_nodes; node; node = node->next)
node->aux = NULL;
return order_pos;
}
+/* Look for all functions inlined to NODE and update their inlined_to pointers
+ to INLINED_TO. */
+
+static void
+update_inlined_to_pointer (struct cgraph_node *node, struct cgraph_node *inlined_to)
+{
+ struct cgraph_edge *e;
+ for (e = node->callees; e; e = e->next_callee)
+ if (e->callee->global.inlined_to)
+ {
+ e->callee->global.inlined_to = inlined_to;
+ update_inlined_to_pointer (e->callee, inlined_to);
+ }
+}
+
/* 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
bool
cgraph_remove_unreachable_nodes (bool before_inlining_p, FILE *file)
{
- struct cgraph_node *first = (void *) 1;
+ struct cgraph_node *first = (struct cgraph_node *) (void *) 1;
struct cgraph_node *node, *next;
bool changed = false;
- int insns = 0;
#ifdef ENABLE_CHECKING
verify_cgraph ();
gcc_assert (!node->aux);
#endif
for (node = cgraph_nodes; node; node = node->next)
- if (node->needed && !node->global.inlined_to
+ if (!cgraph_can_remove_if_no_direct_calls_p (node)
&& ((!DECL_EXTERNAL (node->decl))
|| !node->analyzed
|| before_inlining_p))
{
+ gcc_assert (!node->global.inlined_to);
node->aux = first;
first = node;
}
{
struct cgraph_edge *e;
node = first;
- first = first->aux;
+ first = (struct cgraph_node *) first->aux;
for (e = node->callees; e; e = e->next_callee)
if (!e->callee->aux
e->callee->aux = first;
first = e->callee;
}
+ while (node->clone_of && !node->clone_of->aux && !gimple_has_body_p (node->decl))
+ {
+ node = node->clone_of;
+ node->aux = first;
+ first = node;
+ }
}
/* Remove unreachable nodes. Extern inline functions need special care;
next = node->next;
if (!node->aux)
{
- int local_insns;
- tree decl = node->decl;
-
node->global.inlined_to = NULL;
- if (DECL_STRUCT_FUNCTION (decl))
- local_insns = node->local.self_insns;
- else
- local_insns = 0;
if (file)
fprintf (file, " %s", cgraph_node_name (node));
if (!node->analyzed || !DECL_EXTERNAL (node->decl)
{
struct cgraph_edge *e;
+ /* See if there is reachable caller. */
for (e = node->callers; e; e = e->next_caller)
if (e->caller->aux)
break;
+
+ /* If so, we need to keep node in the callgraph. */
if (e || node->needed)
{
struct cgraph_node *clone;
- for (clone = node->next_clone; clone;
- clone = clone->next_clone)
+ /* If there are still clones, we must keep body around.
+ Otherwise we can just remove the body but keep the clone. */
+ for (clone = node->clones; clone;
+ clone = clone->next_sibling_clone)
if (clone->aux)
break;
if (!clone)
{
cgraph_release_function_body (node);
+ cgraph_node_remove_callees (node);
node->analyzed = false;
+ node->local.inlinable = false;
}
- cgraph_node_remove_callees (node);
- node->analyzed = false;
}
else
cgraph_remove_node (node);
}
- if (!DECL_SAVED_TREE (decl))
- insns += local_insns;
changed = true;
}
}
for (node = cgraph_nodes; node; node = node->next)
- node->aux = NULL;
- if (file)
- fprintf (file, "\nReclaimed %i insns", insns);
+ {
+ /* Inline clones might be kept around so their materializing allows further
+ cloning. If the function the clone is inlined into is removed, we need
+ to turn it into normal cone. */
+ if (node->global.inlined_to
+ && !node->callers)
+ {
+ gcc_assert (node->clones);
+ node->global.inlined_to = NULL;
+ update_inlined_to_pointer (node, node);
+ }
+ node->aux = NULL;
+ }
+#ifdef ENABLE_CHECKING
+ verify_cgraph ();
+#endif
+
+ /* Reclaim alias pairs for functions that have disappeared from the
+ call graph. */
+ remove_unreachable_alias_pairs ();
+
return changed;
}
+
+static bool
+cgraph_externally_visible_p (struct cgraph_node *node, bool whole_program)
+{
+ if (!node->local.finalized)
+ return false;
+ if (!DECL_COMDAT (node->decl)
+ && (!TREE_PUBLIC (node->decl) || DECL_EXTERNAL (node->decl)))
+ return false;
+ if (!whole_program)
+ return true;
+ /* COMDAT functions must be shared only if they have address taken,
+ otherwise we can produce our own private implementation with
+ -fwhole-program. */
+ if (DECL_COMDAT (node->decl) && (node->address_taken || !node->analyzed))
+ return true;
+ if (MAIN_NAME_P (DECL_NAME (node->decl)))
+ return true;
+ if (lookup_attribute ("externally_visible", DECL_ATTRIBUTES (node->decl)))
+ return true;
+ return false;
+}
+
+/* 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)
+{
+ struct cgraph_node *node;
+ struct varpool_node *vnode;
+
+ for (node = cgraph_nodes; node; node = node->next)
+ {
+ gcc_assert ((!DECL_WEAK (node->decl) && !DECL_COMDAT (node->decl))
+ || TREE_PUBLIC (node->decl) || DECL_EXTERNAL (node->decl));
+ if (cgraph_externally_visible_p (node, whole_program))
+ {
+ gcc_assert (!node->global.inlined_to);
+ node->local.externally_visible = true;
+ }
+ else
+ node->local.externally_visible = false;
+ if (!node->local.externally_visible && node->analyzed
+ && !DECL_EXTERNAL (node->decl))
+ {
+ gcc_assert (whole_program || !TREE_PUBLIC (node->decl));
+ TREE_PUBLIC (node->decl) = 0;
+ DECL_COMDAT (node->decl) = 0;
+ DECL_WEAK (node->decl) = 0;
+ }
+ node->local.local = (cgraph_only_called_directly_p (node)
+ && node->analyzed
+ && !DECL_EXTERNAL (node->decl)
+ && !node->local.externally_visible);
+ }
+ for (vnode = varpool_nodes_queue; vnode; vnode = vnode->next_needed)
+ {
+ if (!vnode->finalized)
+ continue;
+ gcc_assert ((!DECL_WEAK (vnode->decl) && !DECL_COMMON (vnode->decl) && !DECL_COMDAT (vnode->decl))
+ || TREE_PUBLIC (vnode->decl) || DECL_EXTERNAL (node->decl));
+ 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)
+ || lookup_attribute ("externally_visible",
+ DECL_ATTRIBUTES (vnode->decl))))
+ vnode->externally_visible = true;
+ else
+ vnode->externally_visible = false;
+ if (!vnode->externally_visible)
+ {
+ gcc_assert (whole_program || !TREE_PUBLIC (vnode->decl));
+ TREE_PUBLIC (vnode->decl) = 0;
+ }
+ gcc_assert (TREE_STATIC (vnode->decl));
+ }
+
+ if (dump_file)
+ {
+ fprintf (dump_file, "\nMarking local functions:");
+ for (node = cgraph_nodes; node; node = node->next)
+ if (node->local.local)
+ fprintf (dump_file, " %s", cgraph_node_name (node));
+ fprintf (dump_file, "\n\n");
+ fprintf (dump_file, "\nMarking externally visible functions:");
+ for (node = cgraph_nodes; node; node = node->next)
+ if (node->local.externally_visible)
+ fprintf (dump_file, " %s", cgraph_node_name (node));
+ fprintf (dump_file, "\n\n");
+ fprintf (dump_file, "\nMarking externally visible variables:");
+ for (vnode = varpool_nodes_queue; vnode; vnode = vnode->next_needed)
+ if (vnode->externally_visible)
+ fprintf (dump_file, " %s", varpool_node_name (vnode));
+ 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 && !flag_whopr);
+}
+
+struct simple_ipa_opt_pass pass_ipa_function_and_variable_visibility =
+{
+ {
+ SIMPLE_IPA_PASS,
+ "visibility", /* name */
+ NULL, /* gate */
+ local_function_and_variable_visibility,/* 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 */
+ TODO_remove_functions | TODO_dump_cgraph/* todo_flags_finish */
+ }
+};
+
+/* Do not re-run on ltrans stage. */
+
+static bool
+gate_whole_program_function_and_variable_visibility (void)
+{
+ return !flag_ltrans;
+}
+
+/* Bring functionss local at LTO time whith -fwhole-program. */
+
+static unsigned int
+whole_program_function_and_variable_visibility (void)
+{
+ struct cgraph_node *node;
+ struct varpool_node *vnode;
+
+ function_and_variable_visibility (flag_whole_program);
+
+ for (node = cgraph_nodes; node; node = node->next)
+ if ((node->local.externally_visible && !DECL_COMDAT (node->decl))
+ && node->local.finalized)
+ cgraph_mark_needed_node (node);
+ for (vnode = varpool_nodes_queue; vnode; vnode = vnode->next_needed)
+ if (vnode->externally_visible && !DECL_COMDAT (vnode->decl))
+ varpool_mark_needed_node (vnode);
+ if (dump_file)
+ {
+ fprintf (dump_file, "\nNeeded variables:");
+ for (vnode = varpool_nodes_queue; vnode; vnode = vnode->next_needed)
+ if (vnode->needed)
+ fprintf (dump_file, " %s", varpool_node_name (vnode));
+ fprintf (dump_file, "\n\n");
+ }
+ return 0;
+}
+
+struct ipa_opt_pass_d pass_ipa_whole_program_visibility =
+{
+ {
+ IPA_PASS,
+ "whole-program", /* name */
+ gate_whole_program_function_and_variable_visibility,/* gate */
+ whole_program_function_and_variable_visibility,/* 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 */
+ TODO_dump_cgraph | TODO_remove_functions/* todo_flags_finish */
+ },
+ NULL, /* generate_summary */
+ NULL, /* write_summary */
+ NULL, /* read_summary */
+ NULL, /* function_read_summary */
+ NULL, /* stmt_fixup */
+ 0, /* TODOs */
+ NULL, /* function_transform */
+ NULL, /* variable_transform */
+};
+
+/* Hash a cgraph node set element. */
+
+static hashval_t
+hash_cgraph_node_set_element (const void *p)
+{
+ const_cgraph_node_set_element element = (const_cgraph_node_set_element) p;
+ return htab_hash_pointer (element->node);
+}
+
+/* Compare two cgraph node set elements. */
+
+static int
+eq_cgraph_node_set_element (const void *p1, const void *p2)
+{
+ const_cgraph_node_set_element e1 = (const_cgraph_node_set_element) p1;
+ const_cgraph_node_set_element e2 = (const_cgraph_node_set_element) p2;
+
+ return e1->node == e2->node;
+}
+
+/* Create a new cgraph node set. */
+
+cgraph_node_set
+cgraph_node_set_new (void)
+{
+ cgraph_node_set new_node_set;
+
+ new_node_set = GGC_NEW (struct cgraph_node_set_def);
+ new_node_set->hashtab = htab_create_ggc (10,
+ hash_cgraph_node_set_element,
+ eq_cgraph_node_set_element,
+ NULL);
+ new_node_set->nodes = NULL;
+ return new_node_set;
+}
+
+/* Add cgraph_node NODE to cgraph_node_set SET. */
+
+void
+cgraph_node_set_add (cgraph_node_set set, struct cgraph_node *node)
+{
+ void **slot;
+ cgraph_node_set_element element;
+ struct cgraph_node_set_element_def dummy;
+
+ dummy.node = node;
+ slot = htab_find_slot (set->hashtab, &dummy, INSERT);
+
+ if (*slot != HTAB_EMPTY_ENTRY)
+ {
+ element = (cgraph_node_set_element) *slot;
+ gcc_assert (node == element->node
+ && (VEC_index (cgraph_node_ptr, set->nodes, element->index)
+ == node));
+ return;
+ }
+
+ /* Insert node into hash table. */
+ element =
+ (cgraph_node_set_element) GGC_NEW (struct cgraph_node_set_element_def);
+ element->node = node;
+ element->index = VEC_length (cgraph_node_ptr, set->nodes);
+ *slot = element;
+
+ /* Insert into node vector. */
+ VEC_safe_push (cgraph_node_ptr, gc, set->nodes, node);
+}
+
+/* Remove cgraph_node NODE from cgraph_node_set SET. */
+
+void
+cgraph_node_set_remove (cgraph_node_set set, struct cgraph_node *node)
+{
+ void **slot, **last_slot;
+ cgraph_node_set_element element, last_element;
+ struct cgraph_node *last_node;
+ struct cgraph_node_set_element_def dummy;
+
+ dummy.node = node;
+ slot = htab_find_slot (set->hashtab, &dummy, NO_INSERT);
+ if (slot == NULL)
+ return;
+
+ element = (cgraph_node_set_element) *slot;
+ gcc_assert (VEC_index (cgraph_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 (cgraph_node_ptr, set->nodes);
+ if (last_node != node)
+ {
+ dummy.node = last_node;
+ last_slot = htab_find_slot (set->hashtab, &dummy, NO_INSERT);
+ last_element = (cgraph_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 (cgraph_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. */
+
+cgraph_node_set_iterator
+cgraph_node_set_find (cgraph_node_set set, struct cgraph_node *node)
+{
+ void **slot;
+ struct cgraph_node_set_element_def dummy;
+ cgraph_node_set_element element;
+ cgraph_node_set_iterator csi;
+
+ dummy.node = node;
+ slot = htab_find_slot (set->hashtab, &dummy, NO_INSERT);
+ if (slot == NULL)
+ csi.index = (unsigned) ~0;
+ else
+ {
+ element = (cgraph_node_set_element) *slot;
+ gcc_assert (VEC_index (cgraph_node_ptr, set->nodes, element->index)
+ == node);
+ csi.index = element->index;
+ }
+ csi.set = set;
+
+ return csi;
+}
+
+/* Dump content of SET to file F. */
+
+void
+dump_cgraph_node_set (FILE *f, cgraph_node_set set)
+{
+ cgraph_node_set_iterator iter;
+
+ for (iter = csi_start (set); !csi_end_p (iter); csi_next (&iter))
+ {
+ struct cgraph_node *node = csi_node (iter);
+ dump_cgraph_node (f, node);
+ }
+}
+
+/* Dump content of SET to stderr. */
+
+void
+debug_cgraph_node_set (cgraph_node_set set)
+{
+ dump_cgraph_node_set (stderr, set);
+}
+