/* Basic IPA optimizations and utilities.
- Copyright (C) 2003, 2004, 2005, 2007, 2008 Free Software Foundation,
- Inc.
+ Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009, 2010
+ Free Software Foundation, Inc.
This file is part of GCC.
#include "timevar.h"
#include "gimple.h"
#include "ggc.h"
+#include "flags.h"
+#include "pointer-set.h"
+#include "target.h"
+#include "tree-iterator.h"
/* Fill array order with all nodes with output flag set in the reverse
topological order. */
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
+ decisions has been made. If BEFORE_INLINING_P is false this function also
removes unneeded bodies of extern inline functions. */
bool
cgraph_remove_unreachable_nodes (bool before_inlining_p, FILE *file)
{
struct cgraph_node *first = (struct cgraph_node *) (void *) 1;
+ 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)
- && ((!DECL_EXTERNAL (node->decl))
- || !node->analyzed
+ if ((!cgraph_can_remove_if_no_direct_calls_and_refs_p (node)
+ /* Keep around virtual functions for possible devirtualization. */
+ || (!before_inlining_p
+ && !node->global.inlined_to
+ && DECL_VIRTUAL_P (node->decl)
+ && (DECL_COMDAT (node->decl) || DECL_EXTERNAL (node->decl))))
+ && ((!DECL_EXTERNAL (node->decl))
|| before_inlining_p))
{
gcc_assert (!node->global.inlined_to);
- node->aux = first;
- first = node;
+ enqueue_cgraph_node (node, &first);
+ node->reachable = true;
}
else
- gcc_assert (!node->aux);
+ {
+ 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;
-
- for (e = node->callees; e; e = e->next_callee)
- if (!e->callee->aux
- && node->analyzed
- && (!e->inline_failed || !e->callee->analyzed
- || (!DECL_EXTERNAL (e->callee->decl))
- || before_inlining_p))
- {
- 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;
+ 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);
+ }
+ process_references (&node->ref_list, &first, &first_varpool, before_inlining_p);
+ }
+
+ /* 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->reachable = true;
+ enqueue_cgraph_node (next, &first);
+ }
+ }
+
+ /* 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 && !node->reachable && !node->aux)
+ {
+ enqueue_cgraph_node (node, &first);
+ break;
+ }
+ }
+ }
+ 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);
+ /* If any function in a comdat group is reachable, force
+ all other functions in the same comdat group to be
+ also reachable. */
+ if (vnode->same_comdat_group)
+ {
+ struct varpool_node *next;
+ for (next = vnode->same_comdat_group;
+ next != vnode;
+ next = next->same_comdat_group)
+ if (!next->needed)
+ {
+ varpool_mark_needed_node (next);
+ enqueue_varpool_node (next, &first_varpool);
+ }
+ }
}
}
- /* 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;
+ if (node->aux && !node->reachable)
+ {
+ cgraph_node_remove_callees (node);
+ ipa_remove_all_references (&node->ref_list);
+ node->analyzed = false;
+ node->local.inlinable = false;
+ }
if (!node->aux)
{
+ struct cgraph_edge *e;
+ bool found = false;
+ int i;
+ struct ipa_ref *ref;
+
node->global.inlined_to = NULL;
if (file)
fprintf (file, " %s", cgraph_node_name (node));
- if (!node->analyzed || !DECL_EXTERNAL (node->decl)
- || before_inlining_p)
- cgraph_remove_node (node);
- else
+ /* See if there is reachable caller. */
+ for (e = node->callers; e && !found; e = e->next_caller)
+ if (e->caller->reachable)
+ found = true;
+ for (i = 0; (ipa_ref_list_refering_iterate (&node->ref_list, i, ref)
+ && !found); i++)
+ if (ref->refering_type == IPA_REF_CGRAPH
+ && ipa_ref_refering_node (ref)->reachable)
+ found = true;
+ else if (ref->refering_type == IPA_REF_VARPOOL
+ && ipa_ref_refering_varpool_node (ref)->needed)
+ found = true;
+
+ /* If so, we need to keep node in the callgraph. */
+ if (found || node->needed)
{
- struct cgraph_edge *e;
-
- /* See if there is reachable caller. */
- for (e = node->callers; e; e = e->next_caller)
- if (e->caller->aux)
- break;
-
- /* If so, we need to keep node in the callgraph. */
- if (e || node->needed)
+ if (node->analyzed)
{
struct cgraph_node *clone;
if (!clone)
{
cgraph_release_function_body (node);
- cgraph_node_remove_callees (node);
- node->analyzed = false;
node->local.inlinable = false;
+ if (node->prev_sibling_clone)
+ node->prev_sibling_clone->next_sibling_clone = node->next_sibling_clone;
+ else if (node->clone_of)
+ node->clone_of->clones = node->next_sibling_clone;
+ if (node->next_sibling_clone)
+ node->next_sibling_clone->prev_sibling_clone = node->prev_sibling_clone;
+ #ifdef ENABLE_CHECKING
+ if (node->clone_of)
+ node->former_clone_of = node->clone_of->decl;
+ #endif
+ node->clone_of = NULL;
+ node->next_sibling_clone = NULL;
+ node->prev_sibling_clone = NULL;
}
+ else
+ gcc_assert (!clone->in_other_partition);
+ node->analyzed = false;
+ changed = true;
+ cgraph_node_remove_callees (node);
+ ipa_remove_all_references (&node->ref_list);
}
- else
- cgraph_remove_node (node);
}
- changed = true;
+ else
+ {
+ cgraph_remove_node (node);
+ changed = true;
+ }
}
}
for (node = cgraph_nodes; node; node = node->next)
}
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 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. */
+
+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)
+cgraph_externally_visible_p (struct cgraph_node *node, bool whole_program, bool aliased)
{
if (!node->local.finalized)
return false;
if (!DECL_COMDAT (node->decl)
&& (!TREE_PUBLIC (node->decl) || DECL_EXTERNAL (node->decl)))
return false;
- if (!whole_program)
+
+ /* Do not even try to be smart about aliased nodes. Until we properly
+ represent everything by same body alias, these are just evil. */
+ if (aliased)
+ return true;
+
+ /* If linker counts on us, we must preserve the function. */
+ if (cgraph_used_from_object_file_p (node))
+ return true;
+ /* 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->analyzed)
+ ;
+ else 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))
+ else if (DECL_COMDAT (node->decl))
+ {
+ if (node->address_taken || !node->analyzed)
+ return true;
+ if (node->same_comdat_group)
+ {
+ struct cgraph_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 (next->address_taken || !next->analyzed)
+ return true;
+ }
+ }
+ if (DECL_PRESERVE_P (node->decl))
return true;
if (MAIN_NAME_P (DECL_NAME (node->decl)))
return true;
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
{
struct cgraph_node *node;
struct varpool_node *vnode;
+ struct pointer_set_t *aliased_nodes = pointer_set_create ();
+ struct pointer_set_t *aliased_vnodes = pointer_set_create ();
+ unsigned i;
+ alias_pair *p;
+
+ /* Discover aliased nodes. */
+ FOR_EACH_VEC_ELT (alias_pair, alias_pairs, i, p)
+ {
+ if (dump_file)
+ fprintf (dump_file, "Alias %s->%s",
+ IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (p->decl)),
+ IDENTIFIER_POINTER (p->target));
+
+ if ((node = cgraph_node_for_asm (p->target)) != NULL)
+ {
+ gcc_assert (node->needed);
+ pointer_set_insert (aliased_nodes, node);
+ if (dump_file)
+ fprintf (dump_file, " node %s/%i",
+ cgraph_node_name (node), node->uid);
+ }
+ else if ((vnode = varpool_node_for_asm (p->target)) != NULL)
+ {
+ gcc_assert (vnode->needed);
+ pointer_set_insert (aliased_vnodes, vnode);
+ if (dump_file)
+ fprintf (dump_file, " varpool node %s",
+ varpool_node_name (vnode));
+ }
+ if (dump_file)
+ fprintf (dump_file, "\n");
+ }
for (node = cgraph_nodes; node; node = node->next)
{
- if (cgraph_externally_visible_p (node, whole_program))
+ /* 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 neccesary 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,
+ and simplifies later passes. */
+ if (node->same_comdat_group && DECL_EXTERNAL (node->decl))
+ {
+#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));
+#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 (cgraph_externally_visible_p (node, whole_program,
+ pointer_set_contains (aliased_nodes,
+ node)))
{
gcc_assert (!node->global.inlined_to);
node->local.externally_visible = true;
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;
+ struct cgraph_node *alias;
+ gcc_assert (whole_program || in_lto_p || !TREE_PUBLIC (node->decl));
+ cgraph_make_decl_local (node->decl);
+ node->resolution = LDPR_PREVAILING_DEF_IRONLY;
+ for (alias = node->same_body; alias; alias = alias->next)
+ cgraph_make_decl_local (alias->decl);
+ if (node->same_comdat_group)
+ /* 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)
+ {
+ /* weak flag makes no sense on local variables. */
+ gcc_assert (!DECL_WEAK (vnode->decl)
+ || 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 (vnode = varpool_nodes_queue; vnode; vnode = vnode->next_needed)
{
continue;
if (vnode->needed
&& (DECL_COMDAT (vnode->decl) || TREE_PUBLIC (vnode->decl))
- && (!whole_program
+ && (((!whole_program
+ /* We can privatize comdat readonly variables whose address is
+ not taken, but doing so is not going to bring us
+ optimization oppurtunities until we start reordering
+ datastructures. */
+ || DECL_COMDAT (vnode->decl)
+ || DECL_WEAK (vnode->decl))
+ /* When doing linktime optimizations, all hidden symbols will
+ become local. */
+ && (!in_lto_p
+ || (DECL_VISIBILITY (vnode->decl) != VISIBILITY_HIDDEN
+ && DECL_VISIBILITY (vnode->decl) != VISIBILITY_INTERNAL)
+ /* We can get prevailing decision in other object file.
+ In this case we do not sed used_from_object_file. */
+ || !vnode->finalized))
+ || DECL_PRESERVE_P (vnode->decl)
+ || varpool_used_from_object_file_p (vnode)
+ || pointer_set_contains (aliased_vnodes, vnode)
|| lookup_attribute ("externally_visible",
DECL_ATTRIBUTES (vnode->decl))))
vnode->externally_visible = true;
vnode->externally_visible = false;
if (!vnode->externally_visible)
{
- gcc_assert (whole_program || !TREE_PUBLIC (vnode->decl));
- TREE_PUBLIC (vnode->decl) = 0;
+ gcc_assert (in_lto_p || whole_program || !TREE_PUBLIC (vnode->decl));
+ cgraph_make_decl_local (vnode->decl);
+ vnode->resolution = LDPR_PREVAILING_DEF_IRONLY;
}
gcc_assert (TREE_STATIC (vnode->decl));
}
+ pointer_set_destroy (aliased_nodes);
+ pointer_set_destroy (aliased_vnodes);
if (dump_file)
{
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;
return function_and_variable_visibility (flag_whole_program && !flag_lto && !flag_whopr);
}
-struct simple_ipa_opt_pass pass_ipa_function_and_variable_visibility =
+struct simple_ipa_opt_pass pass_ipa_function_and_variable_visibility =
{
{
SIMPLE_IPA_PASS,
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 */
}
};
function_and_variable_visibility (flag_whole_program);
for (node = cgraph_nodes; node; node = node->next)
- if (node->local.externally_visible && node->local.finalized)
+ 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)
+ 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");
+ }
+ if (optimize)
+ ipa_discover_readonly_nonaddressable_vars ();
return 0;
}
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 */
NULL, /* variable_transform */
{
cgraph_node_set new_node_set;
- new_node_set = GGC_NEW (struct cgraph_node_set_def);
+ new_node_set = ggc_alloc_cgraph_node_set_def ();
new_node_set->hashtab = htab_create_ggc (10,
hash_cgraph_node_set_element,
eq_cgraph_node_set_element,
}
/* Insert node into hash table. */
- element =
- (cgraph_node_set_element) GGC_NEW (struct cgraph_node_set_element_def);
+ element = ggc_alloc_cgraph_node_set_element_def ();
element->node = node;
element->index = VEC_length (cgraph_node_ptr, set->nodes);
*slot = element;
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);
for (iter = csi_start (set); !csi_end_p (iter); csi_next (&iter))
{
struct cgraph_node *node = csi_node (iter);
- dump_cgraph_node (f, node);
+ fprintf (f, " %s/%i", cgraph_node_name (node), node->uid);
}
+ fprintf (f, "\n");
}
/* Dump content of SET to stderr. */
-void
+DEBUG_FUNCTION void
debug_cgraph_node_set (cgraph_node_set set)
{
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_alloc_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 = ggc_alloc_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);
+ fprintf (f, " %s", varpool_node_name (node));
+ }
+ fprintf (f, "\n");
+}
+
+/* Dump content of SET to stderr. */
+
+DEBUG_FUNCTION 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 */
+};
+
+/* Generate and emit a static constructor or destructor. WHICH must
+ be one of 'I' (for a constructor) or 'D' (for a destructor). BODY
+ is a STATEMENT_LIST containing GENERIC statements. PRIORITY is the
+ initialization priority for this constructor or destructor. */
+
+void
+cgraph_build_static_cdtor (char which, tree body, int priority)
+{
+ static int counter = 0;
+ char which_buf[16];
+ tree decl, name, resdecl;
+
+ /* The priority is encoded in the constructor or destructor name.
+ collect2 will sort the names and arrange that they are called at
+ program startup. */
+ sprintf (which_buf, "%c_%.5d_%d", which, priority, counter++);
+ name = get_file_function_name (which_buf);
+
+ decl = build_decl (input_location, FUNCTION_DECL, name,
+ build_function_type_list (void_type_node, NULL_TREE));
+ current_function_decl = decl;
+
+ resdecl = build_decl (input_location,
+ RESULT_DECL, NULL_TREE, void_type_node);
+ DECL_ARTIFICIAL (resdecl) = 1;
+ DECL_RESULT (decl) = resdecl;
+ DECL_CONTEXT (resdecl) = decl;
+
+ allocate_struct_function (decl, false);
+
+ TREE_STATIC (decl) = 1;
+ TREE_USED (decl) = 1;
+ DECL_ARTIFICIAL (decl) = 1;
+ DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (decl) = 1;
+ DECL_SAVED_TREE (decl) = body;
+ if (!targetm.have_ctors_dtors)
+ {
+ TREE_PUBLIC (decl) = 1;
+ DECL_PRESERVE_P (decl) = 1;
+ }
+ DECL_UNINLINABLE (decl) = 1;
+
+ DECL_INITIAL (decl) = make_node (BLOCK);
+ TREE_USED (DECL_INITIAL (decl)) = 1;
+
+ DECL_SOURCE_LOCATION (decl) = input_location;
+ cfun->function_end_locus = input_location;
+
+ switch (which)
+ {
+ case 'I':
+ DECL_STATIC_CONSTRUCTOR (decl) = 1;
+ decl_init_priority_insert (decl, priority);
+ break;
+ case 'D':
+ DECL_STATIC_DESTRUCTOR (decl) = 1;
+ decl_fini_priority_insert (decl, priority);
+ break;
+ default:
+ gcc_unreachable ();
+ }
+
+ gimplify_function_tree (decl);
+
+ cgraph_add_new_function (decl, false);
+
+ set_cfun (NULL);
+ current_function_decl = NULL;
+}
+
+
+/* A vector of FUNCTION_DECLs declared as static constructors. */
+static VEC(tree, heap) *static_ctors;
+/* A vector of FUNCTION_DECLs declared as static destructors. */
+static VEC(tree, heap) *static_dtors;
+
+/* When target does not have ctors and dtors, we call all constructor
+ and destructor by special initialization/destruction function
+ recognized by collect2.
+
+ When we are going to build this function, collect all constructors and
+ destructors and turn them into normal functions. */
+
+static void
+record_cdtor_fn (struct cgraph_node *node)
+{
+ if (DECL_STATIC_CONSTRUCTOR (node->decl))
+ VEC_safe_push (tree, heap, static_ctors, node->decl);
+ if (DECL_STATIC_DESTRUCTOR (node->decl))
+ VEC_safe_push (tree, heap, static_dtors, node->decl);
+ node = cgraph_node (node->decl);
+ node->local.disregard_inline_limits = 1;
+}
+
+/* Define global constructors/destructor functions for the CDTORS, of
+ which they are LEN. The CDTORS are sorted by initialization
+ priority. If CTOR_P is true, these are constructors; otherwise,
+ they are destructors. */
+
+static void
+build_cdtor (bool ctor_p, VEC (tree, heap) *cdtors)
+{
+ size_t i,j;
+ size_t len = VEC_length (tree, cdtors);
+
+ i = 0;
+ while (i < len)
+ {
+ tree body;
+ tree fn;
+ priority_type priority;
+
+ priority = 0;
+ body = NULL_TREE;
+ j = i;
+ do
+ {
+ priority_type p;
+ fn = VEC_index (tree, cdtors, j);
+ p = ctor_p ? DECL_INIT_PRIORITY (fn) : DECL_FINI_PRIORITY (fn);
+ if (j == i)
+ priority = p;
+ else if (p != priority)
+ break;
+ j++;
+ }
+ while (j < len);
+
+ /* When there is only one cdtor and target supports them, do nothing. */
+ if (j == i + 1
+ && targetm.have_ctors_dtors)
+ {
+ i++;
+ continue;
+ }
+ /* Find the next batch of constructors/destructors with the same
+ initialization priority. */
+ for (;i < j; i++)
+ {
+ tree call;
+ fn = VEC_index (tree, cdtors, i);
+ call = build_call_expr (fn, 0);
+ if (ctor_p)
+ DECL_STATIC_CONSTRUCTOR (fn) = 0;
+ else
+ DECL_STATIC_DESTRUCTOR (fn) = 0;
+ /* We do not want to optimize away pure/const calls here.
+ When optimizing, these should be already removed, when not
+ optimizing, we want user to be able to breakpoint in them. */
+ TREE_SIDE_EFFECTS (call) = 1;
+ append_to_statement_list (call, &body);
+ }
+ gcc_assert (body != NULL_TREE);
+ /* Generate a function to call all the function of like
+ priority. */
+ cgraph_build_static_cdtor (ctor_p ? 'I' : 'D', body, priority);
+ }
+}
+
+/* Comparison function for qsort. P1 and P2 are actually of type
+ "tree *" and point to static constructors. DECL_INIT_PRIORITY is
+ used to determine the sort order. */
+
+static int
+compare_ctor (const void *p1, const void *p2)
+{
+ tree f1;
+ tree f2;
+ int priority1;
+ int priority2;
+
+ f1 = *(const tree *)p1;
+ f2 = *(const tree *)p2;
+ priority1 = DECL_INIT_PRIORITY (f1);
+ priority2 = DECL_INIT_PRIORITY (f2);
+
+ if (priority1 < priority2)
+ return -1;
+ else if (priority1 > priority2)
+ return 1;
+ else
+ /* Ensure a stable sort. Constructors are executed in backwarding
+ order to make LTO initialize braries first. */
+ return DECL_UID (f2) - DECL_UID (f1);
+}
+
+/* Comparison function for qsort. P1 and P2 are actually of type
+ "tree *" and point to static destructors. DECL_FINI_PRIORITY is
+ used to determine the sort order. */
+
+static int
+compare_dtor (const void *p1, const void *p2)
+{
+ tree f1;
+ tree f2;
+ int priority1;
+ int priority2;
+
+ f1 = *(const tree *)p1;
+ f2 = *(const tree *)p2;
+ priority1 = DECL_FINI_PRIORITY (f1);
+ priority2 = DECL_FINI_PRIORITY (f2);
+
+ if (priority1 < priority2)
+ return -1;
+ else if (priority1 > priority2)
+ return 1;
+ else
+ /* Ensure a stable sort. */
+ return DECL_UID (f1) - DECL_UID (f2);
+}
+
+/* Generate functions to call static constructors and destructors
+ for targets that do not support .ctors/.dtors sections. These
+ functions have magic names which are detected by collect2. */
+
+static void
+build_cdtor_fns (void)
+{
+ if (!VEC_empty (tree, static_ctors))
+ {
+ gcc_assert (!targetm.have_ctors_dtors || in_lto_p);
+ VEC_qsort (tree, static_ctors, compare_ctor);
+ build_cdtor (/*ctor_p=*/true, static_ctors);
+ }
+
+ if (!VEC_empty (tree, static_dtors))
+ {
+ gcc_assert (!targetm.have_ctors_dtors || in_lto_p);
+ VEC_qsort (tree, static_dtors, compare_dtor);
+ build_cdtor (/*ctor_p=*/false, static_dtors);
+ }
+}
+
+/* Look for constructors and destructors and produce function calling them.
+ This is needed for targets not supporting ctors or dtors, but we perform the
+ transformation also at linktime to merge possibly numberous
+ constructors/destructors into single function to improve code locality and
+ reduce size. */
+
+static unsigned int
+ipa_cdtor_merge (void)
+{
+ struct cgraph_node *node;
+ for (node = cgraph_nodes; node; node = node->next)
+ if (node->analyzed
+ && (DECL_STATIC_CONSTRUCTOR (node->decl)
+ || DECL_STATIC_DESTRUCTOR (node->decl)))
+ record_cdtor_fn (node);
+ build_cdtor_fns ();
+ VEC_free (tree, heap, static_ctors);
+ VEC_free (tree, heap, static_dtors);
+ return 0;
+}
+
+/* Perform the pass when we have no ctors/dtors support
+ or at LTO time to merge multiple constructors into single
+ function. */
+
+static bool
+gate_ipa_cdtor_merge (void)
+{
+ return !targetm.have_ctors_dtors || (optimize && in_lto_p);
+}
+
+struct ipa_opt_pass_d pass_ipa_cdtor_merge =
+{
+ {
+ IPA_PASS,
+ "cdtor", /* name */
+ gate_ipa_cdtor_merge, /* gate */
+ ipa_cdtor_merge, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_CGRAPHOPT, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ 0 /* todo_flags_finish */
+ },
+ NULL, /* generate_summary */
+ NULL, /* write_summary */
+ NULL, /* read_summary */
+ NULL, /* write_optimization_summary */
+ NULL, /* read_optimization_summary */
+ NULL, /* stmt_fixup */
+ 0, /* TODOs */
+ NULL, /* function_transform */
+ NULL /* variable_transform */
+};
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