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Diffstat (limited to 'contrib/gcc/cgraph.c')
| -rw-r--r-- | contrib/gcc/cgraph.c | 1218 |
1 files changed, 1218 insertions, 0 deletions
diff --git a/contrib/gcc/cgraph.c b/contrib/gcc/cgraph.c new file mode 100644 index 0000000..fcdc02e --- /dev/null +++ b/contrib/gcc/cgraph.c @@ -0,0 +1,1218 @@ +/* Callgraph handling code. + Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc. + Contributed by Jan Hubicka + +This file is part of GCC. + +GCC is free software; you can redistribute it and/or modify it under +the terms of the GNU General Public License as published by the Free +Software Foundation; either version 2, or (at your option) any later +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 COPYING. If not, write to the Free +Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA +02110-1301, USA. */ + +/* This file contains basic routines manipulating call graph and variable pool + +The callgraph: + + The call-graph is data structure designed for intra-procedural optimization + but it is also used in non-unit-at-a-time compilation to allow easier code + sharing. + + The call-graph consist of nodes and edges represented via linked lists. + Each function (external or not) corresponds to the unique node (in + contrast to tree DECL nodes where we can have multiple nodes for each + function). + + The mapping from declarations to call-graph nodes is done using hash table + based on DECL_ASSEMBLER_NAME, so it is essential for assembler name to + not change once the declaration is inserted into the call-graph. + The call-graph nodes are created lazily using cgraph_node function when + called for unknown declaration. + + When built, there is one edge for each direct call. It is possible that + the reference will be later optimized out. The call-graph is built + conservatively in order to make conservative data flow analysis possible. + + The callgraph at the moment does not represent indirect calls or calls + from other compilation unit. Flag NEEDED is set for each node that may + be accessed in such an invisible way and it shall be considered an + entry point to the callgraph. + + Interprocedural information: + + Callgraph is place to store data needed for interprocedural optimization. + All data structures are divided into three components: local_info that + is produced while analyzing the function, global_info that is result + of global walking of the callgraph on the end of compilation and + rtl_info used by RTL backend to propagate data from already compiled + functions to their callers. + + Inlining plans: + + The function inlining information is decided in advance and maintained + in the callgraph as so called inline plan. + For each inlined call, the callee's node is cloned to represent the + new function copy produced by inliner. + Each inlined call gets a unique corresponding clone node of the callee + and the data structure is updated while inlining is performed, so + the clones are eliminated and their callee edges redirected to the + caller. + + Each edge has "inline_failed" field. When the field is set to NULL, + the call will be inlined. When it is non-NULL it contains a reason + why inlining wasn't performed. + + +The varpool data structure: + + Varpool is used to maintain variables in similar manner as call-graph + is used for functions. Most of the API is symmetric replacing cgraph + function prefix by cgraph_varpool */ + + +#include "config.h" +#include "system.h" +#include "coretypes.h" +#include "tm.h" +#include "tree.h" +#include "tree-inline.h" +#include "langhooks.h" +#include "hashtab.h" +#include "toplev.h" +#include "flags.h" +#include "ggc.h" +#include "debug.h" +#include "target.h" +#include "basic-block.h" +#include "cgraph.h" +#include "varray.h" +#include "output.h" +#include "intl.h" +#include "tree-gimple.h" +#include "tree-dump.h" + +static void cgraph_node_remove_callers (struct cgraph_node *node); +static inline void cgraph_edge_remove_caller (struct cgraph_edge *e); +static inline void cgraph_edge_remove_callee (struct cgraph_edge *e); + +/* Hash table used to convert declarations into nodes. */ +static GTY((param_is (struct cgraph_node))) htab_t cgraph_hash; + +/* The linked list of cgraph nodes. */ +struct cgraph_node *cgraph_nodes; + +/* Queue of cgraph nodes scheduled to be lowered. */ +struct cgraph_node *cgraph_nodes_queue; + +/* Queue of cgraph nodes scheduled to be expanded. This is a + secondary queue used during optimization to accommodate passes that + may generate new functions that need to be optimized and expanded. */ +struct cgraph_node *cgraph_expand_queue; + +/* Number of nodes in existence. */ +int cgraph_n_nodes; + +/* Maximal uid used in cgraph nodes. */ +int cgraph_max_uid; + +/* Set when whole unit has been analyzed so we can access global info. */ +bool cgraph_global_info_ready = false; + +/* Set when the cgraph is fully build and the basic flags are computed. */ +bool cgraph_function_flags_ready = false; + +/* Hash table used to convert declarations into nodes. */ +static GTY((param_is (struct cgraph_varpool_node))) htab_t cgraph_varpool_hash; + +/* Queue of cgraph nodes scheduled to be lowered and output. */ +struct cgraph_varpool_node *cgraph_varpool_nodes_queue, *cgraph_varpool_first_unanalyzed_node; + +/* The linked list of cgraph varpool nodes. */ +struct cgraph_varpool_node *cgraph_varpool_nodes; + +/* End of the varpool queue. */ +struct cgraph_varpool_node *cgraph_varpool_last_needed_node; + +/* Linked list of cgraph asm nodes. */ +struct cgraph_asm_node *cgraph_asm_nodes; + +/* Last node in cgraph_asm_nodes. */ +static GTY(()) struct cgraph_asm_node *cgraph_asm_last_node; + +/* The order index of the next cgraph node to be created. This is + used so that we can sort the cgraph nodes in order by when we saw + them, to support -fno-toplevel-reorder. */ +int cgraph_order; + +static hashval_t hash_node (const void *); +static int eq_node (const void *, const void *); + +/* Returns a hash code for P. */ + +static hashval_t +hash_node (const void *p) +{ + const struct cgraph_node *n = (const struct cgraph_node *) p; + return (hashval_t) DECL_UID (n->decl); +} + +/* Returns nonzero if P1 and P2 are equal. */ + +static int +eq_node (const void *p1, const void *p2) +{ + const struct cgraph_node *n1 = (const struct cgraph_node *) p1; + const struct cgraph_node *n2 = (const struct cgraph_node *) p2; + return DECL_UID (n1->decl) == DECL_UID (n2->decl); +} + +/* Allocate new callgraph node and insert it into basic data structures. */ +static struct cgraph_node * +cgraph_create_node (void) +{ + struct cgraph_node *node; + + node = GGC_CNEW (struct cgraph_node); + node->next = cgraph_nodes; + node->uid = cgraph_max_uid++; + node->order = cgraph_order++; + if (cgraph_nodes) + cgraph_nodes->previous = node; + node->previous = NULL; + node->global.estimated_growth = INT_MIN; + cgraph_nodes = node; + cgraph_n_nodes++; + return node; +} + +/* Return cgraph node assigned to DECL. Create new one when needed. */ +struct cgraph_node * +cgraph_node (tree decl) +{ + struct cgraph_node key, *node, **slot; + + gcc_assert (TREE_CODE (decl) == FUNCTION_DECL); + + if (!cgraph_hash) + cgraph_hash = htab_create_ggc (10, hash_node, eq_node, NULL); + + key.decl = decl; + + slot = (struct cgraph_node **) htab_find_slot (cgraph_hash, &key, INSERT); + + if (*slot) + { + node = *slot; + if (!node->master_clone) + node->master_clone = node; + return node; + } + + node = cgraph_create_node (); + node->decl = decl; + *slot = node; + if (DECL_CONTEXT (decl) && TREE_CODE (DECL_CONTEXT (decl)) == FUNCTION_DECL) + { + node->origin = cgraph_node (DECL_CONTEXT (decl)); + node->next_nested = node->origin->nested; + node->origin->nested = node; + node->master_clone = node; + } + return node; +} + +/* Insert already constructed node into hashtable. */ + +void +cgraph_insert_node_to_hashtable (struct cgraph_node *node) +{ + struct cgraph_node **slot; + + slot = (struct cgraph_node **) htab_find_slot (cgraph_hash, node, INSERT); + + gcc_assert (!*slot); + *slot = node; +} + +/* Compare ASMNAME with the DECL_ASSEMBLER_NAME of DECL. */ + +static bool +decl_assembler_name_equal (tree decl, tree asmname) +{ + tree decl_asmname = DECL_ASSEMBLER_NAME (decl); + + if (decl_asmname == asmname) + return true; + + /* If the target assembler name was set by the user, things are trickier. + We have a leading '*' to begin with. After that, it's arguable what + is the correct thing to do with -fleading-underscore. Arguably, we've + historically been doing the wrong thing in assemble_alias by always + printing the leading underscore. Since we're not changing that, make + sure user_label_prefix follows the '*' before matching. */ + if (IDENTIFIER_POINTER (decl_asmname)[0] == '*') + { + const char *decl_str = IDENTIFIER_POINTER (decl_asmname) + 1; + size_t ulp_len = strlen (user_label_prefix); + + if (ulp_len == 0) + ; + else if (strncmp (decl_str, user_label_prefix, ulp_len) == 0) + decl_str += ulp_len; + else + return false; + + return strcmp (decl_str, IDENTIFIER_POINTER (asmname)) == 0; + } + + return false; +} + + +/* Return the cgraph node that has ASMNAME for its DECL_ASSEMBLER_NAME. + Return NULL if there's no such node. */ + +struct cgraph_node * +cgraph_node_for_asm (tree asmname) +{ + struct cgraph_node *node; + + for (node = cgraph_nodes; node ; node = node->next) + if (decl_assembler_name_equal (node->decl, asmname)) + return node; + + return NULL; +} + +/* Returns a hash value for X (which really is a die_struct). */ + +static hashval_t +edge_hash (const void *x) +{ + return htab_hash_pointer (((struct cgraph_edge *) x)->call_stmt); +} + +/* Return nonzero if decl_id of die_struct X is the same as UID of decl *Y. */ + +static int +edge_eq (const void *x, const void *y) +{ + return ((struct cgraph_edge *) x)->call_stmt == y; +} + +/* Return callgraph edge representing CALL_EXPR statement. */ +struct cgraph_edge * +cgraph_edge (struct cgraph_node *node, tree call_stmt) +{ + struct cgraph_edge *e, *e2; + int n = 0; + + if (node->call_site_hash) + return htab_find_with_hash (node->call_site_hash, call_stmt, + htab_hash_pointer (call_stmt)); + + /* This loop may turn out to be performance problem. In such case adding + hashtables into call nodes with very many edges is probably best + solution. It is not good idea to add pointer into CALL_EXPR itself + because we want to make possible having multiple cgraph nodes representing + different clones of the same body before the body is actually cloned. */ + for (e = node->callees; e; e= e->next_callee) + { + if (e->call_stmt == call_stmt) + break; + n++; + } + if (n > 100) + { + node->call_site_hash = htab_create_ggc (120, edge_hash, edge_eq, NULL); + for (e2 = node->callees; e2; e2 = e2->next_callee) + { + void **slot; + slot = htab_find_slot_with_hash (node->call_site_hash, + e2->call_stmt, + htab_hash_pointer (e2->call_stmt), + INSERT); + gcc_assert (!*slot); + *slot = e2; + } + } + return e; +} + +/* Change call_smtt of edge E to NEW_STMT. */ +void +cgraph_set_call_stmt (struct cgraph_edge *e, tree new_stmt) +{ + if (e->caller->call_site_hash) + { + htab_remove_elt_with_hash (e->caller->call_site_hash, + e->call_stmt, + htab_hash_pointer (e->call_stmt)); + } + e->call_stmt = new_stmt; + if (e->caller->call_site_hash) + { + void **slot; + slot = htab_find_slot_with_hash (e->caller->call_site_hash, + e->call_stmt, + htab_hash_pointer + (e->call_stmt), INSERT); + gcc_assert (!*slot); + *slot = e; + } +} + +/* Create edge from CALLER to CALLEE in the cgraph. */ + +struct cgraph_edge * +cgraph_create_edge (struct cgraph_node *caller, struct cgraph_node *callee, + tree call_stmt, gcov_type count, int nest) +{ + struct cgraph_edge *edge = GGC_NEW (struct cgraph_edge); +#ifdef ENABLE_CHECKING + struct cgraph_edge *e; + + for (e = caller->callees; e; e = e->next_callee) + gcc_assert (e->call_stmt != call_stmt); +#endif + + gcc_assert (get_call_expr_in (call_stmt)); + + if (!DECL_SAVED_TREE (callee->decl)) + edge->inline_failed = N_("function body not available"); + else if (callee->local.redefined_extern_inline) + edge->inline_failed = N_("redefined extern inline functions are not " + "considered for inlining"); + else if (callee->local.inlinable) + edge->inline_failed = N_("function not considered for inlining"); + else + edge->inline_failed = N_("function not inlinable"); + + edge->aux = NULL; + + edge->caller = caller; + edge->callee = callee; + edge->call_stmt = call_stmt; + edge->prev_caller = NULL; + edge->next_caller = callee->callers; + if (callee->callers) + callee->callers->prev_caller = edge; + edge->prev_callee = NULL; + edge->next_callee = caller->callees; + if (caller->callees) + caller->callees->prev_callee = edge; + caller->callees = edge; + callee->callers = edge; + edge->count = count; + edge->loop_nest = nest; + if (caller->call_site_hash) + { + void **slot; + slot = htab_find_slot_with_hash (caller->call_site_hash, + edge->call_stmt, + htab_hash_pointer + (edge->call_stmt), + INSERT); + gcc_assert (!*slot); + *slot = edge; + } + return edge; +} + +/* Remove the edge E from the list of the callers of the callee. */ + +static inline void +cgraph_edge_remove_callee (struct cgraph_edge *e) +{ + if (e->prev_caller) + e->prev_caller->next_caller = e->next_caller; + if (e->next_caller) + e->next_caller->prev_caller = e->prev_caller; + if (!e->prev_caller) + e->callee->callers = e->next_caller; +} + +/* Remove the edge E from the list of the callees of the caller. */ + +static inline void +cgraph_edge_remove_caller (struct cgraph_edge *e) +{ + if (e->prev_callee) + e->prev_callee->next_callee = e->next_callee; + if (e->next_callee) + e->next_callee->prev_callee = e->prev_callee; + if (!e->prev_callee) + e->caller->callees = e->next_callee; + if (e->caller->call_site_hash) + htab_remove_elt_with_hash (e->caller->call_site_hash, + e->call_stmt, + htab_hash_pointer (e->call_stmt)); +} + +/* Remove the edge E in the cgraph. */ + +void +cgraph_remove_edge (struct cgraph_edge *e) +{ + /* Remove from callers list of the callee. */ + cgraph_edge_remove_callee (e); + + /* Remove from callees list of the callers. */ + cgraph_edge_remove_caller (e); +} + +/* Redirect callee of E to N. The function does not update underlying + call expression. */ + +void +cgraph_redirect_edge_callee (struct cgraph_edge *e, struct cgraph_node *n) +{ + /* Remove from callers list of the current callee. */ + cgraph_edge_remove_callee (e); + + /* Insert to callers list of the new callee. */ + e->prev_caller = NULL; + if (n->callers) + n->callers->prev_caller = e; + e->next_caller = n->callers; + n->callers = e; + e->callee = n; +} + +/* Remove all callees from the node. */ + +void +cgraph_node_remove_callees (struct cgraph_node *node) +{ + struct cgraph_edge *e; + + /* It is sufficient to remove the edges from the lists of callers of + the callees. The callee list of the node can be zapped with one + assignment. */ + for (e = node->callees; e; e = e->next_callee) + cgraph_edge_remove_callee (e); + node->callees = NULL; + if (node->call_site_hash) + { + htab_delete (node->call_site_hash); + node->call_site_hash = NULL; + } +} + +/* Remove all callers from the node. */ + +static void +cgraph_node_remove_callers (struct cgraph_node *node) +{ + struct cgraph_edge *e; + + /* It is sufficient to remove the edges from the lists of callees of + the callers. The caller list of the node can be zapped with one + assignment. */ + for (e = node->callers; e; e = e->next_caller) + cgraph_edge_remove_caller (e); + node->callers = NULL; +} + +/* Remove the node from cgraph. */ + +void +cgraph_remove_node (struct cgraph_node *node) +{ + void **slot; + bool kill_body = false; + + cgraph_node_remove_callers (node); + cgraph_node_remove_callees (node); + /* Incremental inlining access removed nodes stored in the postorder list. + */ + node->needed = node->reachable = false; + while (node->nested) + cgraph_remove_node (node->nested); + if (node->origin) + { + struct cgraph_node **node2 = &node->origin->nested; + + while (*node2 != node) + node2 = &(*node2)->next_nested; + *node2 = node->next_nested; + } + if (node->previous) + node->previous->next = node->next; + else + cgraph_nodes = node->next; + if (node->next) + node->next->previous = node->previous; + node->next = NULL; + node->previous = NULL; + slot = htab_find_slot (cgraph_hash, node, NO_INSERT); + if (*slot == node) + { + if (node->next_clone) + { + struct cgraph_node *new_node = node->next_clone; + struct cgraph_node *n; + + /* Make the next clone be the master clone */ + for (n = new_node; n; n = n->next_clone) + n->master_clone = new_node; + + *slot = new_node; + node->next_clone->prev_clone = NULL; + } + else + { + htab_clear_slot (cgraph_hash, slot); + kill_body = true; + } + } + else + { + node->prev_clone->next_clone = node->next_clone; + if (node->next_clone) + node->next_clone->prev_clone = node->prev_clone; + } + + /* While all the clones are removed after being proceeded, the function + itself is kept in the cgraph even after it is compiled. Check whether + we are done with this body and reclaim it proactively if this is the case. + */ + if (!kill_body && *slot) + { + struct cgraph_node *n = (struct cgraph_node *) *slot; + if (!n->next_clone && !n->global.inlined_to + && (cgraph_global_info_ready + && (TREE_ASM_WRITTEN (n->decl) || DECL_EXTERNAL (n->decl)))) + kill_body = true; + } + + if (kill_body && flag_unit_at_a_time) + { + DECL_SAVED_TREE (node->decl) = NULL; + DECL_STRUCT_FUNCTION (node->decl) = NULL; + DECL_INITIAL (node->decl) = error_mark_node; + } + node->decl = NULL; + if (node->call_site_hash) + { + htab_delete (node->call_site_hash); + node->call_site_hash = NULL; + } + cgraph_n_nodes--; + /* Do not free the structure itself so the walk over chain can continue. */ +} + +/* Notify finalize_compilation_unit that given node is reachable. */ + +void +cgraph_mark_reachable_node (struct cgraph_node *node) +{ + if (!node->reachable && node->local.finalized) + { + notice_global_symbol (node->decl); + node->reachable = 1; + gcc_assert (!cgraph_global_info_ready); + + node->next_needed = cgraph_nodes_queue; + cgraph_nodes_queue = node; + } +} + +/* Likewise indicate that a node is needed, i.e. reachable via some + external means. */ + +void +cgraph_mark_needed_node (struct cgraph_node *node) +{ + node->needed = 1; + cgraph_mark_reachable_node (node); +} + +/* Return local info for the compiled function. */ + +struct cgraph_local_info * +cgraph_local_info (tree decl) +{ + struct cgraph_node *node; + + gcc_assert (TREE_CODE (decl) == FUNCTION_DECL); + node = cgraph_node (decl); + return &node->local; +} + +/* Return local info for the compiled function. */ + +struct cgraph_global_info * +cgraph_global_info (tree decl) +{ + struct cgraph_node *node; + + gcc_assert (TREE_CODE (decl) == FUNCTION_DECL && cgraph_global_info_ready); + node = cgraph_node (decl); + return &node->global; +} + +/* Return local info for the compiled function. */ + +struct cgraph_rtl_info * +cgraph_rtl_info (tree decl) +{ + struct cgraph_node *node; + + gcc_assert (TREE_CODE (decl) == FUNCTION_DECL); + node = cgraph_node (decl); + if (decl != current_function_decl + && !TREE_ASM_WRITTEN (node->decl)) + return NULL; + return &node->rtl; +} + +/* Return name of the node used in debug output. */ +const char * +cgraph_node_name (struct cgraph_node *node) +{ + return lang_hooks.decl_printable_name (node->decl, 2); +} + +/* Return name of the node used in debug output. */ +static const char * +cgraph_varpool_node_name (struct cgraph_varpool_node *node) +{ + return lang_hooks.decl_printable_name (node->decl, 2); +} + +/* Names used to print out the availability enum. */ +static const char * const availability_names[] = + {"unset", "not_available", "overwrittable", "available", "local"}; + +/* Dump given cgraph node. */ +void +dump_cgraph_node (FILE *f, struct cgraph_node *node) +{ + struct cgraph_edge *edge; + fprintf (f, "%s/%i:", cgraph_node_name (node), node->uid); + if (node->global.inlined_to) + fprintf (f, " (inline copy in %s/%i)", + cgraph_node_name (node->global.inlined_to), + node->global.inlined_to->uid); + if (cgraph_function_flags_ready) + fprintf (f, " availability:%s", + availability_names [cgraph_function_body_availability (node)]); + if (node->master_clone && node->master_clone->uid != node->uid) + fprintf (f, "(%i)", node->master_clone->uid); + if (node->count) + fprintf (f, " executed "HOST_WIDEST_INT_PRINT_DEC"x", + (HOST_WIDEST_INT)node->count); + if (node->local.self_insns) + fprintf (f, " %i insns", node->local.self_insns); + if (node->global.insns && node->global.insns != node->local.self_insns) + fprintf (f, " (%i after inlining)", node->global.insns); + if (node->origin) + fprintf (f, " nested in: %s", cgraph_node_name (node->origin)); + if (node->needed) + fprintf (f, " needed"); + else if (node->reachable) + fprintf (f, " reachable"); + if (DECL_SAVED_TREE (node->decl)) + fprintf (f, " tree"); + if (node->output) + fprintf (f, " output"); + if (node->local.local) + fprintf (f, " local"); + if (node->local.externally_visible) + fprintf (f, " externally_visible"); + if (node->local.finalized) + fprintf (f, " finalized"); + if (node->local.disregard_inline_limits) + fprintf (f, " always_inline"); + else if (node->local.inlinable) + fprintf (f, " inlinable"); + if (node->local.redefined_extern_inline) + fprintf (f, " redefined_extern_inline"); + if (TREE_ASM_WRITTEN (node->decl)) + fprintf (f, " asm_written"); + + fprintf (f, "\n called by: "); + for (edge = node->callers; edge; edge = edge->next_caller) + { + fprintf (f, "%s/%i ", cgraph_node_name (edge->caller), + edge->caller->uid); + if (edge->count) + fprintf (f, "("HOST_WIDEST_INT_PRINT_DEC"x) ", + (HOST_WIDEST_INT)edge->count); + if (!edge->inline_failed) + fprintf(f, "(inlined) "); + } + + fprintf (f, "\n calls: "); + for (edge = node->callees; edge; edge = edge->next_callee) + { + fprintf (f, "%s/%i ", cgraph_node_name (edge->callee), + edge->callee->uid); + if (!edge->inline_failed) + fprintf(f, "(inlined) "); + if (edge->count) + fprintf (f, "("HOST_WIDEST_INT_PRINT_DEC"x) ", + (HOST_WIDEST_INT)edge->count); + if (edge->loop_nest) + fprintf (f, "(nested in %i loops) ", edge->loop_nest); + } + fprintf (f, "\n"); +} + +/* Dump the callgraph. */ + +void +dump_cgraph (FILE *f) +{ + struct cgraph_node *node; + + fprintf (f, "callgraph:\n\n"); + for (node = cgraph_nodes; node; node = node->next) + dump_cgraph_node (f, node); +} + +/* Dump given cgraph node. */ +void +dump_cgraph_varpool_node (FILE *f, struct cgraph_varpool_node *node) +{ + fprintf (f, "%s:", cgraph_varpool_node_name (node)); + fprintf (f, " availability:%s", + cgraph_function_flags_ready + ? availability_names[cgraph_variable_initializer_availability (node)] + : "not-ready"); + if (DECL_INITIAL (node->decl)) + fprintf (f, " initialized"); + if (node->needed) + fprintf (f, " needed"); + if (node->analyzed) + fprintf (f, " analyzed"); + if (node->finalized) + fprintf (f, " finalized"); + if (node->output) + fprintf (f, " output"); + if (node->externally_visible) + fprintf (f, " externally_visible"); + fprintf (f, "\n"); +} + +/* Dump the callgraph. */ + +void +dump_varpool (FILE *f) +{ + struct cgraph_varpool_node *node; + + fprintf (f, "variable pool:\n\n"); + for (node = cgraph_varpool_nodes; node; node = node->next_needed) + dump_cgraph_varpool_node (f, node); +} + +/* Returns a hash code for P. */ + +static hashval_t +hash_varpool_node (const void *p) +{ + const struct cgraph_varpool_node *n = (const struct cgraph_varpool_node *) p; + return (hashval_t) DECL_UID (n->decl); +} + +/* Returns nonzero if P1 and P2 are equal. */ + +static int +eq_varpool_node (const void *p1, const void *p2) +{ + const struct cgraph_varpool_node *n1 = + (const struct cgraph_varpool_node *) p1; + const struct cgraph_varpool_node *n2 = + (const struct cgraph_varpool_node *) p2; + return DECL_UID (n1->decl) == DECL_UID (n2->decl); +} + +/* Return cgraph_varpool node assigned to DECL. Create new one when needed. */ +struct cgraph_varpool_node * +cgraph_varpool_node (tree decl) +{ + struct cgraph_varpool_node key, *node, **slot; + + gcc_assert (DECL_P (decl) && TREE_CODE (decl) != FUNCTION_DECL); + + if (!cgraph_varpool_hash) + cgraph_varpool_hash = htab_create_ggc (10, hash_varpool_node, + eq_varpool_node, NULL); + key.decl = decl; + slot = (struct cgraph_varpool_node **) + htab_find_slot (cgraph_varpool_hash, &key, INSERT); + if (*slot) + return *slot; + node = GGC_CNEW (struct cgraph_varpool_node); + node->decl = decl; + node->order = cgraph_order++; + node->next = cgraph_varpool_nodes; + cgraph_varpool_nodes = node; + *slot = node; + return node; +} + +struct cgraph_varpool_node * +cgraph_varpool_node_for_asm (tree asmname) +{ + struct cgraph_varpool_node *node; + + for (node = cgraph_varpool_nodes; node ; node = node->next) + if (decl_assembler_name_equal (node->decl, asmname)) + return node; + + return NULL; +} + +/* Set the DECL_ASSEMBLER_NAME and update cgraph hashtables. */ +void +change_decl_assembler_name (tree decl, tree name) +{ + if (!DECL_ASSEMBLER_NAME_SET_P (decl)) + { + SET_DECL_ASSEMBLER_NAME (decl, name); + return; + } + if (name == DECL_ASSEMBLER_NAME (decl)) + return; + + if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)) + && DECL_RTL_SET_P (decl)) + warning (0, "%D renamed after being referenced in assembly", decl); + + SET_DECL_ASSEMBLER_NAME (decl, name); +} + +/* Helper function for finalization code - add node into lists so it will + be analyzed and compiled. */ +void +cgraph_varpool_enqueue_needed_node (struct cgraph_varpool_node *node) +{ + if (cgraph_varpool_last_needed_node) + cgraph_varpool_last_needed_node->next_needed = node; + cgraph_varpool_last_needed_node = node; + node->next_needed = NULL; + if (!cgraph_varpool_nodes_queue) + cgraph_varpool_nodes_queue = node; + if (!cgraph_varpool_first_unanalyzed_node) + cgraph_varpool_first_unanalyzed_node = node; + notice_global_symbol (node->decl); +} + +/* Reset the queue of needed nodes. */ +void +cgraph_varpool_reset_queue (void) +{ + cgraph_varpool_last_needed_node = NULL; + cgraph_varpool_nodes_queue = NULL; + cgraph_varpool_first_unanalyzed_node = NULL; +} + +/* Notify finalize_compilation_unit that given node is reachable + or needed. */ +void +cgraph_varpool_mark_needed_node (struct cgraph_varpool_node *node) +{ + if (!node->needed && node->finalized + && !TREE_ASM_WRITTEN (node->decl)) + cgraph_varpool_enqueue_needed_node (node); + node->needed = 1; +} + +/* Determine if variable DECL is needed. That is, visible to something + either outside this translation unit, something magic in the system + configury, or (if not doing unit-at-a-time) to something we haven't + seen yet. */ + +bool +decide_is_variable_needed (struct cgraph_varpool_node *node, tree decl) +{ + /* If the user told us it is used, then it must be so. */ + if (node->externally_visible) + return true; + if (!flag_unit_at_a_time + && lookup_attribute ("used", DECL_ATTRIBUTES (decl))) + return true; + + /* ??? If the assembler name is set by hand, it is possible to assemble + the name later after finalizing the function and the fact is noticed + in assemble_name then. This is arguably a bug. */ + if (DECL_ASSEMBLER_NAME_SET_P (decl) + && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))) + return true; + + /* If we decided it was needed before, but at the time we didn't have + the definition available, then it's still needed. */ + if (node->needed) + return true; + + /* Externally visible variables must be output. The exception is + COMDAT variables that must be output only when they are needed. */ + if (TREE_PUBLIC (decl) && !flag_whole_program && !DECL_COMDAT (decl) + && !DECL_EXTERNAL (decl)) + return true; + + /* When not reordering top level variables, we have to assume that + we are going to keep everything. */ + if (flag_unit_at_a_time && flag_toplevel_reorder) + return false; + + /* We want to emit COMDAT variables only when absolutely necessary. */ + if (DECL_COMDAT (decl)) + return false; + return true; +} + +void +cgraph_varpool_finalize_decl (tree decl) +{ + struct cgraph_varpool_node *node = cgraph_varpool_node (decl); + + /* The first declaration of a variable that comes through this function + decides whether it is global (in C, has external linkage) + or local (in C, has internal linkage). So do nothing more + if this function has already run. */ + if (node->finalized) + { + if (cgraph_global_info_ready || (!flag_unit_at_a_time && !flag_openmp)) + cgraph_varpool_assemble_pending_decls (); + return; + } + if (node->needed) + cgraph_varpool_enqueue_needed_node (node); + node->finalized = true; + + if (decide_is_variable_needed (node, decl)) + cgraph_varpool_mark_needed_node (node); + /* Since we reclaim unreachable nodes at the end of every language + level unit, we need to be conservative about possible entry points + there. */ + else if (TREE_PUBLIC (decl) && !DECL_COMDAT (decl) && !DECL_EXTERNAL (decl)) + cgraph_varpool_mark_needed_node (node); + if (cgraph_global_info_ready || (!flag_unit_at_a_time && !flag_openmp)) + cgraph_varpool_assemble_pending_decls (); +} + +/* Add a top-level asm statement to the list. */ + +struct cgraph_asm_node * +cgraph_add_asm_node (tree asm_str) +{ + struct cgraph_asm_node *node; + + node = GGC_CNEW (struct cgraph_asm_node); + node->asm_str = asm_str; + node->order = cgraph_order++; + node->next = NULL; + if (cgraph_asm_nodes == NULL) + cgraph_asm_nodes = node; + else + cgraph_asm_last_node->next = node; + cgraph_asm_last_node = node; + return node; +} + +/* Return true when the DECL can possibly be inlined. */ +bool +cgraph_function_possibly_inlined_p (tree decl) +{ + if (!cgraph_global_info_ready) + return (DECL_INLINE (decl) && !flag_really_no_inline); + return DECL_POSSIBLY_INLINED (decl); +} + +/* Create clone of E in the node N represented by CALL_EXPR the callgraph. */ +struct cgraph_edge * +cgraph_clone_edge (struct cgraph_edge *e, struct cgraph_node *n, + tree call_stmt, gcov_type count_scale, int loop_nest, + bool update_original) +{ + struct cgraph_edge *new; + + new = cgraph_create_edge (n, e->callee, call_stmt, + e->count * count_scale / REG_BR_PROB_BASE, + e->loop_nest + loop_nest); + + new->inline_failed = e->inline_failed; + if (update_original) + { + e->count -= new->count; + if (e->count < 0) + e->count = 0; + } + return new; +} + +/* Create node representing clone of N executed COUNT times. Decrease + the execution counts from original node too. + + When UPDATE_ORIGINAL is true, the counts are subtracted from the original + function's profile to reflect the fact that part of execution is handled + by node. */ +struct cgraph_node * +cgraph_clone_node (struct cgraph_node *n, gcov_type count, int loop_nest, + bool update_original) +{ + struct cgraph_node *new = cgraph_create_node (); + struct cgraph_edge *e; + gcov_type count_scale; + + new->decl = n->decl; + new->origin = n->origin; + if (new->origin) + { + new->next_nested = new->origin->nested; + new->origin->nested = new; + } + new->analyzed = n->analyzed; + new->local = n->local; + new->global = n->global; + new->rtl = n->rtl; + new->master_clone = n->master_clone; + new->count = count; + if (n->count) + count_scale = new->count * REG_BR_PROB_BASE / n->count; + else + count_scale = 0; + if (update_original) + { + n->count -= count; + if (n->count < 0) + n->count = 0; + } + + for (e = n->callees;e; e=e->next_callee) + cgraph_clone_edge (e, new, e->call_stmt, count_scale, loop_nest, + update_original); + + new->next_clone = n->next_clone; + new->prev_clone = n; + n->next_clone = new; + if (new->next_clone) + new->next_clone->prev_clone = new; + + return new; +} + +/* Return true if N is an master_clone, (see cgraph_master_clone). */ + +bool +cgraph_is_master_clone (struct cgraph_node *n) +{ + return (n == cgraph_master_clone (n)); +} + +struct cgraph_node * +cgraph_master_clone (struct cgraph_node *n) +{ + enum availability avail = cgraph_function_body_availability (n); + + if (avail == AVAIL_NOT_AVAILABLE || avail == AVAIL_OVERWRITABLE) + return NULL; + + if (!n->master_clone) + n->master_clone = cgraph_node (n->decl); + + return n->master_clone; +} + +/* NODE is no longer nested function; update cgraph accordingly. */ +void +cgraph_unnest_node (struct cgraph_node *node) +{ + struct cgraph_node **node2 = &node->origin->nested; + gcc_assert (node->origin); + + while (*node2 != node) + node2 = &(*node2)->next_nested; + *node2 = node->next_nested; + node->origin = NULL; +} + +/* Return function availability. See cgraph.h for description of individual + return values. */ +enum availability +cgraph_function_body_availability (struct cgraph_node *node) +{ + enum availability avail; + gcc_assert (cgraph_function_flags_ready); + if (!node->analyzed) + avail = AVAIL_NOT_AVAILABLE; + else if (node->local.local) + avail = AVAIL_LOCAL; + else if (node->local.externally_visible) + avail = AVAIL_AVAILABLE; + + /* If the function can be overwritten, return OVERWRITABLE. Take + care at least of two notable extensions - the COMDAT functions + used to share template instantiations in C++ (this is symmetric + to code cp_cannot_inline_tree_fn and probably shall be shared and + the inlinability hooks completely eliminated). + + ??? Does the C++ one definition rule allow us to always return + AVAIL_AVAILABLE here? That would be good reason to preserve this + hook Similarly deal with extern inline functions - this is again + necessary to get C++ shared functions having keyed templates + right and in the C extension documentation we probably should + document the requirement of both versions of function (extern + inline and offline) having same side effect characteristics as + good optimization is what this optimization is about. */ + + else if (!(*targetm.binds_local_p) (node->decl) + && !DECL_COMDAT (node->decl) && !DECL_EXTERNAL (node->decl)) + avail = AVAIL_OVERWRITABLE; + else avail = AVAIL_AVAILABLE; + + return avail; +} + +/* Return variable availability. See cgraph.h for description of individual + return values. */ +enum availability +cgraph_variable_initializer_availability (struct cgraph_varpool_node *node) +{ + gcc_assert (cgraph_function_flags_ready); + if (!node->finalized) + return AVAIL_NOT_AVAILABLE; + if (!TREE_PUBLIC (node->decl)) + return AVAIL_AVAILABLE; + /* If the variable can be overwritten, return OVERWRITABLE. Takes + care of at least two notable extensions - the COMDAT variables + used to share template instantiations in C++. */ + if (!(*targetm.binds_local_p) (node->decl) && !DECL_COMDAT (node->decl)) + return AVAIL_OVERWRITABLE; + return AVAIL_AVAILABLE; +} + + +/* Add the function FNDECL to the call graph. FNDECL is assumed to be + in low GIMPLE form and ready to be processed by cgraph_finalize_function. + + When operating in unit-at-a-time, a new callgraph node is added to + CGRAPH_EXPAND_QUEUE, which is processed after all the original + functions in the call graph . + + When not in unit-at-a-time, the new callgraph node is added to + CGRAPH_NODES_QUEUE for cgraph_assemble_pending_functions to + process. */ + +void +cgraph_add_new_function (tree fndecl) +{ + struct cgraph_node *n = cgraph_node (fndecl); + n->next_needed = cgraph_expand_queue; + cgraph_expand_queue = n; +} + +#include "gt-cgraph.h" |
