| /* Basic IPA optimizations and utilities. |
| Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009, 2010, 2011 |
| 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 3, or (at your option) any later |
| version. |
| |
| GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
| WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| for more details. |
| |
| You should have received a copy of the GNU General Public License |
| 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" |
| #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. */ |
| |
| int |
| cgraph_postorder (struct cgraph_node **order) |
| { |
| struct cgraph_node *node, *node2; |
| 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 inline functions. */ |
| for (node = cgraph_nodes; node; node = node->next) |
| node->aux = NULL; |
| for (pass = 0; pass < 2; pass++) |
| for (node = cgraph_nodes; node; node = node->next) |
| if (!node->aux |
| && (pass |
| || (!node->address_taken |
| && !node->global.inlined_to |
| && !cgraph_only_called_directly_p (node)))) |
| { |
| 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; |
| /* 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) |
| 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); |
| } |
| } |
| |
| /* 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 |
| && node->analyzed |
| && (!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 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 |
| 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 |
| verify_cgraph (); |
| #endif |
| if (file) |
| fprintf (file, "\nReclaiming functions:"); |
| #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 (); |
| /* 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 |
| cgraph_can_remove_if_no_direct_calls_and_refs_p should not be called on them. */ |
| for (node = cgraph_nodes; node; node = node->next) |
| if (node->analyzed && !node->global.inlined_to |
| && (!cgraph_can_remove_if_no_direct_calls_and_refs_p (node) |
| /* Keep around virtual functions for possible devirtualization. */ |
| || (before_inlining_p |
| && DECL_VIRTUAL_P (node->decl) |
| && (DECL_COMDAT (node->decl) || DECL_EXTERNAL (node->decl))) |
| /* Also external functions with address taken are better to stay |
| for indirect inlining. */ |
| || (before_inlining_p |
| && DECL_EXTERNAL (node->decl) |
| && node->address_taken))) |
| { |
| gcc_assert (!node->global.inlined_to); |
| enqueue_cgraph_node (node, &first); |
| node->reachable = true; |
| } |
| else |
| { |
| gcc_assert (!node->aux); |
| node->reachable = false; |
| } |
| |
| /* Mark variables that are obviously needed. */ |
| for (vnode = varpool_nodes; vnode; vnode = vnode->next) |
| { |
| vnode->next_needed = NULL; |
| vnode->prev_needed = NULL; |
| if ((vnode->analyzed || vnode->force_output) |
| && !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. |
| |
| 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) |
| { |
| 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 |
| || !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. |
| |
| 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)); |
| /* 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) |
| { |
| if (node->analyzed) |
| { |
| struct cgraph_node *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); |
| 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; |
| if (node->clone_of) |
| node->former_clone_of = node->clone_of->decl; |
| 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; |
| } |
| } |
| } |
| for (node = cgraph_nodes; node; node = node->next) |
| { |
| /* 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; |
| } |
| |
| 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 |
| |
| /* Reclaim alias pairs for functions that have disappeared from the |
| call graph. */ |
| remove_unreachable_alias_pairs (); |
| |
| 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 there is a reference to node and it is not vtable. */ |
| static bool |
| cgraph_address_taken_from_non_vtable_p (struct cgraph_node *node) |
| { |
| int i; |
| struct ipa_ref *ref; |
| for (i = 0; ipa_ref_list_reference_iterate (&node->ref_list, i, ref); i++) |
| { |
| struct varpool_node *node; |
| if (ref->refered_type == IPA_REF_CGRAPH) |
| return true; |
| node = ipa_ref_varpool_node (ref); |
| if (!DECL_VIRTUAL_P (node->decl)) |
| return true; |
| } |
| return false; |
| } |
| |
| /* 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. */ |
| |
| bool |
| cgraph_comdat_can_be_unshared_p (struct cgraph_node *node) |
| { |
| if ((cgraph_address_taken_from_non_vtable_p (node) |
| && !DECL_VIRTUAL_P (node->decl)) |
| || !node->analyzed) |
| return false; |
| 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 (cgraph_address_taken_from_non_vtable_p (node) |
| && !DECL_VIRTUAL_P (next->decl)) |
| return false; |
| } |
| return true; |
| } |
| |
| /* Return true when function NODE should be considered externally visible. */ |
| |
| static bool |
| cgraph_externally_visible_p (struct cgraph_node *node, bool whole_program, bool aliased) |
| { |
| struct cgraph_node *alias; |
| if (!node->local.finalized) |
| return false; |
| if (!DECL_COMDAT (node->decl) |
| && (!TREE_PUBLIC (node->decl) || DECL_EXTERNAL (node->decl))) |
| return false; |
| |
| /* Do not even try to be smart about aliased nodes. Until we properly |
| represent everything by same body alias, these are just evil. */ |
| if (aliased) |
| return true; |
| |
| /* 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; |
| |
| /* FIXME: We get wrong symbols with asm aliases in callgraph and LTO. |
| This is because very little of code knows that assembler name needs to |
| mangled. Avoid touching declarations with user asm name set to mask |
| some of the problems. */ |
| if (DECL_ASSEMBLER_NAME_SET_P (node->decl) |
| && IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (node->decl))[0]=='*') |
| return true; |
| |
| /* If linker counts on us, we must preserve the function. */ |
| if (cgraph_used_from_object_file_p (node)) |
| return true; |
| if (DECL_PRESERVE_P (node->decl)) |
| return true; |
| if (lookup_attribute ("externally_visible", DECL_ATTRIBUTES (node->decl))) |
| return true; |
| if (TARGET_DLLIMPORT_DECL_ATTRIBUTES |
| && lookup_attribute ("dllexport", DECL_ATTRIBUTES (node->decl))) |
| return true; |
| /* 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) |
| && cgraph_comdat_can_be_unshared_p (node)) |
| return false; |
| |
| /* 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. */ |
| for (alias = node->same_body; alias; alias = alias->next) |
| if (alias->resolution != LDPR_PREVAILING_DEF_IRONLY) |
| break; |
| if (!alias && node->resolution == LDPR_PREVAILING_DEF_IRONLY) |
| 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->analyzed) |
| ; |
| else if (!whole_program) |
| return true; |
| |
| if (MAIN_NAME_P (DECL_NAME (node->decl))) |
| return true; |
| |
| return false; |
| } |
| |
| /* Return true when variable VNODE should be considered externally visible. */ |
| |
| static bool |
| varpool_externally_visible_p (struct varpool_node *vnode, bool aliased) |
| { |
| struct varpool_node *alias; |
| if (!DECL_COMDAT (vnode->decl) && !TREE_PUBLIC (vnode->decl)) |
| return false; |
| |
| /* Do not even try to be smart about aliased nodes. Until we properly |
| represent everything by same body alias, these are just evil. */ |
| if (aliased) |
| return true; |
| |
| /* If linker counts on us, we must preserve the function. */ |
| if (varpool_used_from_object_file_p (vnode)) |
| return true; |
| |
| /* FIXME: We get wrong symbols with asm aliases in callgraph and LTO. |
| This is because very little of code knows that assembler name needs to |
| mangled. Avoid touching declarations with user asm name set to mask |
| some of the problems. */ |
| if (DECL_ASSEMBLER_NAME_SET_P (vnode->decl) |
| && IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (vnode->decl))[0]=='*') |
| 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 (varpool_used_from_object_file_p (vnode)) |
| return true; |
| for (alias = vnode->extra_name; alias; alias = alias->next) |
| if (alias->resolution != LDPR_PREVAILING_DEF_IRONLY) |
| break; |
| if (!alias && vnode->resolution == LDPR_PREVAILING_DEF_IRONLY) |
| return false; |
| |
| /* As a special case, the COMDAT virutal 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) |
| && !vnode->force_output |
| && DECL_COMDAT (vnode->decl) && DECL_VIRTUAL_P (vnode->decl)) |
| 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->finalized) |
| ; |
| else if (!flag_whole_program) |
| return true; |
| |
| /* Do not attempt to privatize COMDATS by default. |
| This would break linking with C++ libraries sharing |
| inline definitions. |
| |
| FIXME: We can do so for readonly vars with no address taken and |
| possibly also for vtables since no direct pointer comparsion is done. |
| It might be interesting to do so to reduce linking overhead. */ |
| if (DECL_COMDAT (vnode->decl) || DECL_WEAK (vnode->decl)) |
| return true; |
| return false; |
| } |
| |
| /* 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 |
| 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; |
| 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 |
| && !DECL_EXTERNAL (node->decl)) |
| { |
| if (!node->analyzed) |
| continue; |
| /* Weakrefs alias symbols from other compilation unit. In the case |
| the destination of weakref became available because of LTO, we must |
| mark it as needed. */ |
| if (in_lto_p |
| && lookup_attribute ("weakref", DECL_ATTRIBUTES (p->decl)) |
| && !node->needed) |
| cgraph_mark_needed_node (node); |
| 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 |
| && !DECL_EXTERNAL (vnode->decl)) |
| { |
| /* Weakrefs alias symbols from other compilation unit. In the case |
| the destination of weakref became available because of LTO, we must |
| mark it as needed. */ |
| if (in_lto_p |
| && lookup_attribute ("weakref", DECL_ATTRIBUTES (p->decl)) |
| && !vnode->needed) |
| varpool_mark_needed_node (vnode); |
| 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) |
| { |
| 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 (node->needed |
| && (DECL_EXTERNAL (node->decl) || !node->analyzed)) |
| node->needed = 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 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; |
| } |
| else |
| node->local.externally_visible = false; |
| if (!node->local.externally_visible && node->analyzed |
| && !DECL_EXTERNAL (node->decl)) |
| { |
| 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_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) |
| { |
| if (!vnode->finalized) |
| continue; |
| if (vnode->needed |
| && varpool_externally_visible_p |
| (vnode, |
| pointer_set_contains (aliased_vnodes, vnode))) |
| vnode->externally_visible = true; |
| else |
| vnode->externally_visible = false; |
| if (!vnode->externally_visible) |
| { |
| 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) |
| { |
| 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); |
| } |
| |
| 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_ggc_collect /* 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"); |
| } |
| if (optimize) |
| ipa_discover_readonly_nonaddressable_vars (); |
| 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_remove_functions | TODO_dump_cgraph |
| | TODO_ggc_collect /* 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 */ |
| }; |
| |
| /* 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_alloc_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 = ggc_alloc_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); |
| fprintf (f, " %s/%i", cgraph_node_name (node), node->uid); |
| } |
| fprintf (f, "\n"); |
| } |
| |
| /* Dump content of SET to stderr. */ |
| |
| 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. |
| |
| FINAL specify whether the externally visible name for collect2 should |
| be produced. */ |
| |
| static void |
| cgraph_build_static_cdtor_1 (char which, tree body, int priority, bool final) |
| { |
| 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. */ |
| if (final) |
| sprintf (which_buf, "%c_%.5d_%d", which, priority, counter++); |
| else |
| /* Proudce sane name but one not recognizable by collect2, just for the |
| case we fail to inline the function. */ |
| sprintf (which_buf, "sub_%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 && final) |
| { |
| 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; |
| } |
| |
| /* 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) |
| { |
| cgraph_build_static_cdtor_1 (which, body, priority, false); |
| } |
| |
| /* 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_1 (ctor_p ? 'I' : 'D', body, priority, true); |
| } |
| } |
| |
| /* 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 */ |
| }; |