diff options
Diffstat (limited to 'gcc/cgraph.cc')
| -rw-r--r-- | gcc/cgraph.cc | 290 |
1 files changed, 279 insertions, 11 deletions
diff --git a/gcc/cgraph.cc b/gcc/cgraph.cc index 07966a6..d1b2e2a 100644 --- a/gcc/cgraph.cc +++ b/gcc/cgraph.cc @@ -69,6 +69,7 @@ along with GCC; see the file COPYING3. If not see #include "tree-nested.h" #include "symtab-thunks.h" #include "symtab-clones.h" +#include "attr-callback.h" /* FIXME: Only for PROP_loops, but cgraph shouldn't have to know about this. */ #include "tree-pass.h" @@ -871,11 +872,22 @@ cgraph_add_edge_to_call_site_hash (cgraph_edge *e) one indirect); always hash the direct one. */ if (e->speculative && e->indirect_unknown_callee) return; + /* We always want to hash the carrying edge of a callback, not the edges + pointing to the callbacks themselves, as their call statement doesn't + exist. */ + if (e->callback) + return; cgraph_edge **slot = e->caller->call_site_hash->find_slot_with_hash (e->call_stmt, cgraph_edge_hasher::hash (e->call_stmt), INSERT); if (*slot) { - gcc_assert (((cgraph_edge *)*slot)->speculative); + cgraph_edge *edge = (cgraph_edge *) *slot; + gcc_assert (edge->speculative || edge->has_callback); + if (edge->has_callback) + /* If the slot is already occupied, then the hashed edge is the + callback-carrying edge, which is desired behavior, so we can safely + return. */ + gcc_checking_assert (edge == e); if (e->callee && (!e->prev_callee || !e->prev_callee->speculative || e->prev_callee->call_stmt != e->call_stmt)) @@ -919,6 +931,13 @@ cgraph_node::get_edge (gimple *call_stmt) n++; } + /* We want to work with the callback-carrying edge whenever possible. When it + comes to callback edges, a call statement might have multiple callback + edges attached to it. These can be easily obtained from the carrying edge + instead. */ + if (e && e->callback) + e = e->get_callback_carrying_edge (); + if (n > 100) { call_site_hash = hash_table<cgraph_edge_hasher>::create_ggc (120); @@ -931,15 +950,16 @@ cgraph_node::get_edge (gimple *call_stmt) return e; } - -/* Change field call_stmt of edge E to NEW_STMT. If UPDATE_SPECULATIVE and E +/* Change field call_stmt of edge E to NEW_STMT. If UPDATE_DERIVED_EDGES and E is any component of speculative edge, then update all components. - Speculations can be resolved in the process and EDGE can be removed and - deallocated. Return the edge that now represents the call. */ + speculations can be resolved in the process and edge can be removed and + deallocated. if update_derived_edges and e is a part of a callback pair, + update all associated edges and return their carrying edge. return the edge + that now represents the call. */ cgraph_edge * cgraph_edge::set_call_stmt (cgraph_edge *e, gcall *new_stmt, - bool update_speculative) + bool update_derived_edges) { tree decl; @@ -955,7 +975,7 @@ cgraph_edge::set_call_stmt (cgraph_edge *e, gcall *new_stmt, /* Speculative edges has three component, update all of them when asked to. */ - if (update_speculative && e->speculative + if (update_derived_edges && e->speculative /* If we are about to resolve the speculation by calling make_direct below, do not bother going over all the speculative edges now. */ && !new_direct_callee) @@ -991,6 +1011,27 @@ cgraph_edge::set_call_stmt (cgraph_edge *e, gcall *new_stmt, if (new_direct_callee) e = make_direct (e, new_direct_callee); + /* When updating a callback or a callback-carrying edge, update every edge + involved. */ + if (update_derived_edges && (e->callback || e->has_callback)) + { + cgraph_edge *current, *next, *carrying; + carrying = e->has_callback ? e : e->get_callback_carrying_edge (); + + current = e->first_callback_edge (); + if (current) + { + for (cgraph_edge *d = current; d; d = next) + { + next = d->next_callback_edge (); + cgraph_edge *d2 = set_call_stmt (d, new_stmt, false); + gcc_assert (d2 == d); + } + } + carrying = set_call_stmt (carrying, new_stmt, false); + return carrying; + } + /* Only direct speculative edges go to call_site_hash. */ if (e->caller->call_site_hash && (!e->speculative || !e->indirect_unknown_callee) @@ -1036,7 +1077,7 @@ symbol_table::create_edge (cgraph_node *caller, cgraph_node *callee, construction of call stmt hashtable. */ cgraph_edge *e; gcc_checking_assert (!(e = caller->get_edge (call_stmt)) - || e->speculative); + || e->speculative || e->has_callback || e->callback); gcc_assert (is_gimple_call (call_stmt)); } @@ -1063,6 +1104,9 @@ symbol_table::create_edge (cgraph_node *caller, cgraph_node *callee, edge->indirect_info = NULL; edge->indirect_inlining_edge = 0; edge->speculative = false; + edge->has_callback = false; + edge->callback = false; + edge->callback_id = 0; edge->indirect_unknown_callee = indir_unknown_callee; if (call_stmt && caller->call_site_hash) cgraph_add_edge_to_call_site_hash (edge); @@ -1286,6 +1330,119 @@ cgraph_edge::make_speculative (cgraph_node *n2, profile_count direct_count, return e2; } +/* Create a callback edge calling N2. Callback edges + never get turned into actual calls, they are just used + as clues and allow for optimizing functions which do not + have any callsites during compile time, e.g. functions + passed to standard library functions. + + The edge will be attached to the same call statement as + the callback-carrying edge, which is the instance this method + is called on. + + callback_id is used to pair the returned edge with the attribute that + originated it. + + Return the resulting callback edge. */ + +cgraph_edge * +cgraph_edge::make_callback (cgraph_node *n2, unsigned int callback_id) +{ + cgraph_node *n = caller; + cgraph_edge *e2; + + has_callback = true; + e2 = n->create_edge (n2, call_stmt, count); + if (dump_file) + fprintf ( + dump_file, + "Created callback edge %s -> %s belonging to carrying edge %s -> %s\n", + e2->caller->dump_name (), e2->callee->dump_name (), caller->dump_name (), + callee->dump_name ()); + e2->inline_failed = CIF_CALLBACK_EDGE; + e2->callback = true; + e2->callback_id = callback_id; + if (TREE_NOTHROW (n2->decl)) + e2->can_throw_external = false; + else + e2->can_throw_external = can_throw_external; + e2->lto_stmt_uid = lto_stmt_uid; + n2->mark_address_taken (); + return e2; +} + +/* Returns the callback_carrying edge of a callback edge on which + it is called on or NULL when no such edge can be found. + + An edge is taken to be the callback-carrying if it has it's has_callback + flag set and the edges share their call statements. */ + +cgraph_edge * +cgraph_edge::get_callback_carrying_edge () +{ + gcc_checking_assert (callback); + cgraph_edge *e; + for (e = caller->callees; e; e = e->next_callee) + { + if (e->has_callback && e->call_stmt == call_stmt + && e->lto_stmt_uid == lto_stmt_uid) + break; + } + return e; +} + +/* Returns the first callback edge in the list of callees of the caller node. + Note that the edges might be in arbitrary order. Must be called on a + callback or callback-carrying edge. */ + +cgraph_edge * +cgraph_edge::first_callback_edge () +{ + gcc_checking_assert (has_callback || callback); + cgraph_edge *e = NULL; + for (e = caller->callees; e; e = e->next_callee) + { + if (e->callback && e->call_stmt == call_stmt + && e->lto_stmt_uid == lto_stmt_uid) + break; + } + return e; +} + +/* Given a callback edge, returns the next callback edge belonging to the same + carrying edge. Must be called on a callback edge, not the callback-carrying + edge. */ + +cgraph_edge * +cgraph_edge::next_callback_edge () +{ + gcc_checking_assert (callback); + cgraph_edge *e = NULL; + for (e = next_callee; e; e = e->next_callee) + { + if (e->callback && e->call_stmt == call_stmt + && e->lto_stmt_uid == lto_stmt_uid) + break; + } + return e; +} + +/* When called on a callback-carrying edge, removes all of its attached callback + edges and sets has_callback to FALSE. */ + +void +cgraph_edge::purge_callback_edges () +{ + gcc_checking_assert (has_callback); + cgraph_edge *e, *next; + for (e = first_callback_edge (); e; e = next) + { + next = e->next_callback_edge (); + cgraph_edge::remove (e); + } + has_callback = false; +} + /* Speculative call consists of an indirect edge and one or more direct edge+ref pairs. @@ -1521,12 +1678,27 @@ void cgraph_edge::redirect_callee (cgraph_node *n) { bool loc = callee->comdat_local_p (); + cgraph_node *old_callee = callee; + /* Remove from callers list of the current callee. */ remove_callee (); /* Insert to callers list of the new callee. */ set_callee (n); + if (callback) + { + /* When redirecting a callback callee, redirect its ref as well. */ + ipa_ref *old_ref = caller->find_reference (old_callee, call_stmt, + lto_stmt_uid, IPA_REF_ADDR); + gcc_checking_assert(old_ref); + old_ref->remove_reference (); + ipa_ref *new_ref = caller->create_reference (n, IPA_REF_ADDR, call_stmt); + new_ref->lto_stmt_uid = lto_stmt_uid; + if (!old_callee->referred_to_p ()) + old_callee->address_taken = 0; + } + if (!inline_failed) return; if (!loc && n->comdat_local_p ()) @@ -1643,6 +1815,27 @@ cgraph_edge::redirect_call_stmt_to_callee (cgraph_edge *e, || decl == e->callee->decl) return e->call_stmt; + /* When redirecting a callback edge, all we need to do is replace + the original address with the address of the function we are + redirecting to. */ + if (e->callback) + { + cgraph_edge *carrying = e->get_callback_carrying_edge (); + if (!callback_is_special_cased (carrying->callee->decl, e->call_stmt) + && !lookup_attribute (CALLBACK_ATTR_IDENT, + DECL_ATTRIBUTES (carrying->callee->decl))) + /* Callback attribute is removed if the dispatching function changes + signature, as the indices wouldn't be correct anymore. These edges + will get cleaned up later, ignore their redirection for now. */ + return e->call_stmt; + int fn_idx = callback_fetch_fn_position (e, carrying); + tree previous_arg = gimple_call_arg (e->call_stmt, fn_idx); + location_t loc = EXPR_LOCATION (previous_arg); + tree new_addr = build_fold_addr_expr_loc (loc, e->callee->decl); + gimple_call_set_arg (e->call_stmt, fn_idx, new_addr); + return e->call_stmt; + } + if (decl && ipa_saved_clone_sources) { tree *p = ipa_saved_clone_sources->get (e->callee); @@ -1752,7 +1945,9 @@ cgraph_edge::redirect_call_stmt_to_callee (cgraph_edge *e, maybe_remove_unused_call_args (DECL_STRUCT_FUNCTION (e->caller->decl), new_stmt); - e->caller->set_call_stmt_including_clones (e->call_stmt, new_stmt, false); + /* Update callback edges if setting the carrying edge's statement, or else + their pairing would fall apart. */ + e->caller->set_call_stmt_including_clones (e->call_stmt, new_stmt, e->has_callback); if (symtab->dump_file) { @@ -1944,6 +2139,17 @@ cgraph_node::remove_callers (void) for (e = callers; e; e = f) { f = e->next_caller; + /* When removing a callback-carrying edge, remove all its attached edges + as well. */ + if (e->has_callback) + { + cgraph_edge *cbe, *next_cbe = NULL; + for (cbe = e->first_callback_edge (); cbe; cbe = next_cbe) + { + next_cbe = cbe->next_callback_edge (); + cgraph_edge::remove (cbe); + } + } symtab->call_edge_removal_hooks (e); e->remove_caller (); symtab->free_edge (e); @@ -2253,6 +2459,10 @@ cgraph_edge::dump_edge_flags (FILE *f) { if (speculative) fprintf (f, "(speculative) "); + if (callback) + fprintf (f, "(callback) "); + if (has_callback) + fprintf (f, "(has_callback) "); if (!inline_failed) fprintf (f, "(inlined) "); if (call_stmt_cannot_inline_p) @@ -3866,6 +4076,8 @@ cgraph_node::verify_node (void) if (gimple_has_body_p (e->caller->decl) && !e->caller->inlined_to && !e->speculative + && !e->callback + && !e->has_callback /* Optimized out calls are redirected to __builtin_unreachable. */ && (e->count.nonzero_p () || ! e->callee->decl @@ -4071,7 +4283,12 @@ cgraph_node::verify_node (void) } if (!e->indirect_unknown_callee) { - if (e->verify_corresponds_to_fndecl (decl)) + /* Callback edges violate this assertion + because their call statement doesn't exist, + their associated statement belongs to the + callback-dispatching function. */ + if (!e->callback + && e->verify_corresponds_to_fndecl (decl)) { error ("edge points to wrong declaration:"); debug_tree (e->callee->decl); @@ -4113,7 +4330,58 @@ cgraph_node::verify_node (void) for (e = callees; e; e = e->next_callee) { - if (!e->aux && !e->speculative) + if (!e->callback && e->callback_id) + { + error ("non-callback edge has callback_id set"); + error_found = true; + } + + if (e->callback && e->has_callback) + { + error ("edge has both callback and has_callback set"); + error_found = true; + } + + if (e->callback) + { + if (!e->get_callback_carrying_edge ()) + { + error ("callback edge %s->%s has no callback-carrying", + identifier_to_locale (e->caller->name ()), + identifier_to_locale (e->callee->name ())); + error_found = true; + } + } + + if (e->has_callback + && !callback_is_special_cased (e->callee->decl, e->call_stmt)) + { + int ncallbacks = 0; + int nfound_edges = 0; + for (tree cb = lookup_attribute (CALLBACK_ATTR_IDENT, DECL_ATTRIBUTES ( + e->callee->decl)); + cb; cb = lookup_attribute (CALLBACK_ATTR_IDENT, TREE_CHAIN (cb)), + ncallbacks++) + ; + for (cgraph_edge *cbe = callees; cbe; cbe = cbe->next_callee) + { + if (cbe->callback && cbe->call_stmt == e->call_stmt + && cbe->lto_stmt_uid == e->lto_stmt_uid) + { + nfound_edges++; + } + } + if (ncallbacks < nfound_edges) + { + error ("callback edge %s->%s callback edge count mismatch, " + "expected at most %d, found %d", + identifier_to_locale (e->caller->name ()), + identifier_to_locale (e->callee->name ()), ncallbacks, + nfound_edges); + } + } + + if (!e->aux && !e->speculative && !e->callback && !e->has_callback) { error ("edge %s->%s has no corresponding call_stmt", identifier_to_locale (e->caller->name ()), |