/* Pass for parsing functions with multiple target attributes. Contributed by Evgeny Stupachenko Copyright (C) 2015-2017 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 . */ #include "config.h" #include "system.h" #include "coretypes.h" #include "backend.h" #include "tree.h" #include "stringpool.h" #include "gimple.h" #include "diagnostic-core.h" #include "gimple-ssa.h" #include "cgraph.h" #include "tree-pass.h" #include "target.h" #include "attribs.h" #include "pretty-print.h" /* If the call in NODE has multiple target attribute with multiple fields, replace it with dispatcher call and create dispatcher (once). */ static void create_dispatcher_calls (struct cgraph_node *node) { cgraph_edge *e; cgraph_edge *e_next = NULL; /* We need to remember NEXT_CALLER as it could be modified in the loop. */ for (e = node->callers; e ;e = (e == NULL) ? e_next : e->next_caller) { tree resolver_decl; tree idecl; tree decl; gimple *call = e->call_stmt; struct cgraph_node *inode; /* Checking if call of function is call of versioned function. Versioned function are not inlined, so there is no need to check for inline. */ if (!call || !(decl = gimple_call_fndecl (call)) || !DECL_FUNCTION_VERSIONED (decl)) continue; if (!targetm.has_ifunc_p ()) { error_at (gimple_location (call), "the call requires ifunc, which is not" " supported by this target"); break; } else if (!targetm.get_function_versions_dispatcher) { error_at (gimple_location (call), "target does not support function version dispatcher"); break; } e_next = e->next_caller; idecl = targetm.get_function_versions_dispatcher (decl); if (!idecl) { error_at (gimple_location (call), "default target_clones attribute was not set"); break; } inode = cgraph_node::get (idecl); gcc_assert (inode); resolver_decl = targetm.generate_version_dispatcher_body (inode); /* Update aliases. */ inode->alias = true; inode->alias_target = resolver_decl; if (!inode->analyzed) inode->resolve_alias (cgraph_node::get (resolver_decl)); e->redirect_callee (inode); e->redirect_call_stmt_to_callee (); /* Since REDIRECT_CALLEE modifies NEXT_CALLER field we move to previously set NEXT_CALLER. */ e = NULL; } } /* Return length of attribute names string, if arglist chain > 1, -1 otherwise. */ static int get_attr_len (tree arglist) { tree arg; int str_len_sum = 0; int argnum = 0; for (arg = arglist; arg; arg = TREE_CHAIN (arg)) { const char *str = TREE_STRING_POINTER (TREE_VALUE (arg)); size_t len = strlen (str); str_len_sum += len + 1; for (const char *p = strchr (str, ','); p; p = strchr (p + 1, ',')) argnum++; argnum++; } if (argnum <= 1) return -1; return str_len_sum; } /* Create string with attributes separated by comma. Return number of attributes. */ static int get_attr_str (tree arglist, char *attr_str) { tree arg; size_t str_len_sum = 0; int argnum = 0; for (arg = arglist; arg; arg = TREE_CHAIN (arg)) { const char *str = TREE_STRING_POINTER (TREE_VALUE (arg)); size_t len = strlen (str); for (const char *p = strchr (str, ','); p; p = strchr (p + 1, ',')) argnum++; memcpy (attr_str + str_len_sum, str, len); attr_str[str_len_sum + len] = TREE_CHAIN (arg) ? ',' : '\0'; str_len_sum += len + 1; argnum++; } return argnum; } /* Return number of attributes separated by comma and put them into ARGS. If there is no DEFAULT attribute return -1. */ static int separate_attrs (char *attr_str, char **attrs) { int i = 0; bool has_default = false; for (char *attr = strtok (attr_str, ","); attr != NULL; attr = strtok (NULL, ",")) { if (strcmp (attr, "default") == 0) { has_default = true; continue; } attrs[i++] = attr; } if (!has_default) return -1; return i; } /* Return true if symbol is valid in assembler name. */ static bool is_valid_asm_symbol (char c) { if ('a' <= c && c <= 'z') return true; if ('A' <= c && c <= 'Z') return true; if ('0' <= c && c <= '9') return true; if (c == '_') return true; return false; } /* Replace all not valid assembler symbols with '_'. */ static void create_new_asm_name (char *old_asm_name, char *new_asm_name) { int i; int old_name_len = strlen (old_asm_name); /* Replace all not valid assembler symbols with '_'. */ for (i = 0; i < old_name_len; i++) if (!is_valid_asm_symbol (old_asm_name[i])) new_asm_name[i] = '_'; else new_asm_name[i] = old_asm_name[i]; new_asm_name[old_name_len] = '\0'; } /* Creates target clone of NODE. */ static cgraph_node * create_target_clone (cgraph_node *node, bool definition, char *name) { cgraph_node *new_node; if (definition) { new_node = node->create_version_clone_with_body (vNULL, NULL, NULL, false, NULL, NULL, name); new_node->force_output = true; } else { tree new_decl = copy_node (node->decl); new_node = cgraph_node::get_create (new_decl); /* Generate a new name for the new version. */ symtab->change_decl_assembler_name (new_node->decl, clone_function_name (node->decl, name)); } return new_node; } /* If the function in NODE has multiple target attributes create the appropriate clone for each valid target attribute. */ static bool expand_target_clones (struct cgraph_node *node, bool definition) { int i; /* Parsing target attributes separated by comma. */ tree attr_target = lookup_attribute ("target_clones", DECL_ATTRIBUTES (node->decl)); /* No targets specified. */ if (!attr_target) return false; tree arglist = TREE_VALUE (attr_target); int attr_len = get_attr_len (arglist); /* No need to clone for 1 target attribute. */ if (attr_len == -1) { warning_at (DECL_SOURCE_LOCATION (node->decl), 0, "single target_clones attribute is ignored"); return false; } char *attr_str = XNEWVEC (char, attr_len); int attrnum = get_attr_str (arglist, attr_str); char **attrs = XNEWVEC (char *, attrnum); attrnum = separate_attrs (attr_str, attrs); if (attrnum == -1) { error_at (DECL_SOURCE_LOCATION (node->decl), "default target was not set"); XDELETEVEC (attrs); XDELETEVEC (attr_str); return false; } cgraph_function_version_info *decl1_v = NULL; cgraph_function_version_info *decl2_v = NULL; cgraph_function_version_info *before = NULL; cgraph_function_version_info *after = NULL; decl1_v = node->function_version (); if (decl1_v == NULL) decl1_v = node->insert_new_function_version (); before = decl1_v; DECL_FUNCTION_VERSIONED (node->decl) = 1; for (i = 0; i < attrnum; i++) { char *attr = attrs[i]; char *suffix = XNEWVEC (char, strlen (attr) + 1); create_new_asm_name (attr, suffix); /* Create new target clone. */ cgraph_node *new_node = create_target_clone (node, definition, suffix); new_node->local.local = false; XDELETEVEC (suffix); /* Set new attribute for the clone. */ tree attributes = make_attribute ("target", attr, DECL_ATTRIBUTES (new_node->decl)); DECL_ATTRIBUTES (new_node->decl) = attributes; location_t saved_loc = input_location; input_location = DECL_SOURCE_LOCATION (node->decl); if (!targetm.target_option.valid_attribute_p (new_node->decl, NULL, TREE_VALUE (attributes), 0)) return false; input_location = saved_loc; decl2_v = new_node->function_version (); if (decl2_v != NULL) continue; decl2_v = new_node->insert_new_function_version (); /* Chain decl2_v and decl1_v. All semantically identical versions will be chained together. */ after = decl2_v; while (before->next != NULL) before = before->next; while (after->prev != NULL) after = after->prev; before->next = after; after->prev = before; DECL_FUNCTION_VERSIONED (new_node->decl) = 1; } XDELETEVEC (attrs); XDELETEVEC (attr_str); /* Setting new attribute to initial function. */ tree attributes = make_attribute ("target", "default", DECL_ATTRIBUTES (node->decl)); DECL_ATTRIBUTES (node->decl) = attributes; node->local.local = false; location_t saved_loc = input_location; input_location = DECL_SOURCE_LOCATION (node->decl); bool ret = targetm.target_option.valid_attribute_p (node->decl, NULL, TREE_VALUE (attributes), 0); input_location = saved_loc; return ret; } static unsigned int ipa_target_clone (void) { struct cgraph_node *node; bool target_clone_pass = false; FOR_EACH_FUNCTION (node) target_clone_pass |= expand_target_clones (node, node->definition); if (target_clone_pass) FOR_EACH_FUNCTION (node) create_dispatcher_calls (node); return 0; } namespace { const pass_data pass_data_target_clone = { SIMPLE_IPA_PASS, /* type */ "targetclone", /* name */ OPTGROUP_NONE, /* optinfo_flags */ TV_NONE, /* tv_id */ ( PROP_ssa | PROP_cfg ), /* properties_required */ 0, /* properties_provided */ 0, /* properties_destroyed */ 0, /* todo_flags_start */ TODO_update_ssa /* todo_flags_finish */ }; class pass_target_clone : public simple_ipa_opt_pass { public: pass_target_clone (gcc::context *ctxt) : simple_ipa_opt_pass (pass_data_target_clone, ctxt) {} /* opt_pass methods: */ virtual bool gate (function *); virtual unsigned int execute (function *) { return ipa_target_clone (); } }; bool pass_target_clone::gate (function *) { return true; } } // anon namespace simple_ipa_opt_pass * make_pass_target_clone (gcc::context *ctxt) { return new pass_target_clone (ctxt); }