GCC plugin infrastructure

This patch allows to build the whole kernel with GCC plugins. It was ported from
grsecurity/PaX. The infrastructure supports building out-of-tree modules and
building in a separate directory. Cross-compilation is supported too.
Currently the x86, arm, arm64 and uml architectures enable plugins.

The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory
there. The plugins compile with these options:
 * -fno-rtti: gcc is compiled with this option so the plugins must use it too
 * -fno-exceptions: this is inherited from gcc too
 * -fasynchronous-unwind-tables: this is inherited from gcc too
 * -ggdb: it is useful for debugging a plugin (better backtrace on internal
    errors)
 * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h)
 * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version
    variable, plugin-version.h)

The infrastructure introduces a new Makefile target called gcc-plugins. It
supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script
chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++).
This script also checks the availability of the included headers in
scripts/gcc-plugins/gcc-common.h.

The gcc-common.h header contains frequently included headers for GCC plugins
and it has a compatibility layer for the supported gcc versions.

The gcc-generate-*-pass.h headers automatically generate the registration
structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes.

Note that 'make clean' keeps the *.so files (only the distclean or mrproper
targets clean all) because they are needed for out-of-tree modules.

Based on work created by the PaX Team.

Signed-off-by: Emese Revfy <re.emese@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Michal Marek <mmarek@suse.com>
diff --git a/scripts/gcc-plugins/gcc-common.h b/scripts/gcc-plugins/gcc-common.h
new file mode 100644
index 0000000..172850b
--- /dev/null
+++ b/scripts/gcc-plugins/gcc-common.h
@@ -0,0 +1,830 @@
+#ifndef GCC_COMMON_H_INCLUDED
+#define GCC_COMMON_H_INCLUDED
+
+#include "bversion.h"
+#if BUILDING_GCC_VERSION >= 6000
+#include "gcc-plugin.h"
+#else
+#include "plugin.h"
+#endif
+#include "plugin-version.h"
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
+#include "line-map.h"
+#include "input.h"
+#include "tree.h"
+
+#include "tree-inline.h"
+#include "version.h"
+#include "rtl.h"
+#include "tm_p.h"
+#include "flags.h"
+#include "hard-reg-set.h"
+#include "output.h"
+#include "except.h"
+#include "function.h"
+#include "toplev.h"
+#include "basic-block.h"
+#include "intl.h"
+#include "ggc.h"
+#include "timevar.h"
+
+#include "params.h"
+
+#if BUILDING_GCC_VERSION <= 4009
+#include "pointer-set.h"
+#else
+#include "hash-map.h"
+#endif
+
+#include "emit-rtl.h"
+#include "debug.h"
+#include "target.h"
+#include "langhooks.h"
+#include "cfgloop.h"
+#include "cgraph.h"
+#include "opts.h"
+
+#if BUILDING_GCC_VERSION == 4005
+#include <sys/mman.h>
+#endif
+
+#if BUILDING_GCC_VERSION >= 4007
+#include "tree-pretty-print.h"
+#include "gimple-pretty-print.h"
+#endif
+
+#if BUILDING_GCC_VERSION >= 4006
+#include "c-family/c-common.h"
+#else
+#include "c-common.h"
+#endif
+
+#if BUILDING_GCC_VERSION <= 4008
+#include "tree-flow.h"
+#else
+#include "tree-cfgcleanup.h"
+#include "tree-ssa-operands.h"
+#include "tree-into-ssa.h"
+#endif
+
+#if BUILDING_GCC_VERSION >= 4008
+#include "is-a.h"
+#endif
+
+#include "diagnostic.h"
+#include "tree-dump.h"
+#include "tree-pass.h"
+#include "predict.h"
+#include "ipa-utils.h"
+
+#if BUILDING_GCC_VERSION >= 4009
+#include "attribs.h"
+#include "varasm.h"
+#include "stor-layout.h"
+#include "internal-fn.h"
+#include "gimple-expr.h"
+#include "gimple-fold.h"
+#include "context.h"
+#include "tree-ssa-alias.h"
+#include "tree-ssa.h"
+#include "stringpool.h"
+#include "tree-ssanames.h"
+#include "print-tree.h"
+#include "tree-eh.h"
+#include "stmt.h"
+#include "gimplify.h"
+#endif
+
+#include "gimple.h"
+
+#if BUILDING_GCC_VERSION >= 4009
+#include "tree-ssa-operands.h"
+#include "tree-phinodes.h"
+#include "tree-cfg.h"
+#include "gimple-iterator.h"
+#include "gimple-ssa.h"
+#include "ssa-iterators.h"
+#endif
+
+#if BUILDING_GCC_VERSION >= 5000
+#include "builtins.h"
+#endif
+
+/* #include "expr.h" where are you... */
+extern rtx emit_move_insn(rtx x, rtx y);
+
+/* missing from basic_block.h... */
+extern void debug_dominance_info(enum cdi_direction dir);
+extern void debug_dominance_tree(enum cdi_direction dir, basic_block root);
+
+#if BUILDING_GCC_VERSION == 4006
+extern void debug_gimple_stmt(gimple);
+extern void debug_gimple_seq(gimple_seq);
+extern void print_gimple_seq(FILE *, gimple_seq, int, int);
+extern void print_gimple_stmt(FILE *, gimple, int, int);
+extern void print_gimple_expr(FILE *, gimple, int, int);
+extern void dump_gimple_stmt(pretty_printer *, gimple, int, int);
+#endif
+
+#define __unused __attribute__((__unused__))
+
+#define DECL_NAME_POINTER(node) IDENTIFIER_POINTER(DECL_NAME(node))
+#define DECL_NAME_LENGTH(node) IDENTIFIER_LENGTH(DECL_NAME(node))
+#define TYPE_NAME_POINTER(node) IDENTIFIER_POINTER(TYPE_NAME(node))
+#define TYPE_NAME_LENGTH(node) IDENTIFIER_LENGTH(TYPE_NAME(node))
+
+/* should come from c-tree.h if only it were installed for gcc 4.5... */
+#define C_TYPE_FIELDS_READONLY(TYPE) TREE_LANG_FLAG_1(TYPE)
+
+#if BUILDING_GCC_VERSION == 4005
+#define FOR_EACH_LOCAL_DECL(FUN, I, D)			\
+	for (tree vars = (FUN)->local_decls, (I) = 0;	\
+		vars && ((D) = TREE_VALUE(vars));	\
+		vars = TREE_CHAIN(vars), (I)++)
+#define DECL_CHAIN(NODE) (TREE_CHAIN(DECL_MINIMAL_CHECK(NODE)))
+#define FOR_EACH_VEC_ELT(T, V, I, P) \
+	for (I = 0; VEC_iterate(T, (V), (I), (P)); ++(I))
+#define TODO_rebuild_cgraph_edges 0
+#define SCOPE_FILE_SCOPE_P(EXP) (!(EXP))
+
+#ifndef O_BINARY
+#define O_BINARY 0
+#endif
+
+typedef struct varpool_node *varpool_node_ptr;
+
+static inline bool gimple_call_builtin_p(gimple stmt, enum built_in_function code)
+{
+	tree fndecl;
+
+	if (!is_gimple_call(stmt))
+		return false;
+	fndecl = gimple_call_fndecl(stmt);
+	if (!fndecl || DECL_BUILT_IN_CLASS(fndecl) != BUILT_IN_NORMAL)
+		return false;
+	return DECL_FUNCTION_CODE(fndecl) == code;
+}
+
+static inline bool is_simple_builtin(tree decl)
+{
+	if (decl && DECL_BUILT_IN_CLASS(decl) != BUILT_IN_NORMAL)
+		return false;
+
+	switch (DECL_FUNCTION_CODE(decl)) {
+	/* Builtins that expand to constants. */
+	case BUILT_IN_CONSTANT_P:
+	case BUILT_IN_EXPECT:
+	case BUILT_IN_OBJECT_SIZE:
+	case BUILT_IN_UNREACHABLE:
+	/* Simple register moves or loads from stack. */
+	case BUILT_IN_RETURN_ADDRESS:
+	case BUILT_IN_EXTRACT_RETURN_ADDR:
+	case BUILT_IN_FROB_RETURN_ADDR:
+	case BUILT_IN_RETURN:
+	case BUILT_IN_AGGREGATE_INCOMING_ADDRESS:
+	case BUILT_IN_FRAME_ADDRESS:
+	case BUILT_IN_VA_END:
+	case BUILT_IN_STACK_SAVE:
+	case BUILT_IN_STACK_RESTORE:
+	/* Exception state returns or moves registers around. */
+	case BUILT_IN_EH_FILTER:
+	case BUILT_IN_EH_POINTER:
+	case BUILT_IN_EH_COPY_VALUES:
+	return true;
+
+	default:
+	return false;
+	}
+}
+
+static inline void add_local_decl(struct function *fun, tree d)
+{
+	gcc_assert(TREE_CODE(d) == VAR_DECL);
+	fun->local_decls = tree_cons(NULL_TREE, d, fun->local_decls);
+}
+#endif
+
+#if BUILDING_GCC_VERSION <= 4006
+#define ANY_RETURN_P(rtx) (GET_CODE(rtx) == RETURN)
+#define C_DECL_REGISTER(EXP) DECL_LANG_FLAG_4(EXP)
+#define EDGE_PRESERVE 0ULL
+#define HOST_WIDE_INT_PRINT_HEX_PURE "%" HOST_WIDE_INT_PRINT "x"
+#define flag_fat_lto_objects true
+
+#define get_random_seed(noinit) ({						\
+	unsigned HOST_WIDE_INT seed;						\
+	sscanf(get_random_seed(noinit), "%" HOST_WIDE_INT_PRINT "x", &seed);	\
+	seed * seed; })
+
+#define int_const_binop(code, arg1, arg2)	\
+	int_const_binop((code), (arg1), (arg2), 0)
+
+static inline bool gimple_clobber_p(gimple s __unused)
+{
+	return false;
+}
+
+static inline bool gimple_asm_clobbers_memory_p(const_gimple stmt)
+{
+	unsigned i;
+
+	for (i = 0; i < gimple_asm_nclobbers(stmt); i++) {
+		tree op = gimple_asm_clobber_op(stmt, i);
+
+		if (!strcmp(TREE_STRING_POINTER(TREE_VALUE(op)), "memory"))
+			return true;
+	}
+
+	return false;
+}
+
+static inline tree builtin_decl_implicit(enum built_in_function fncode)
+{
+	return implicit_built_in_decls[fncode];
+}
+
+static inline int ipa_reverse_postorder(struct cgraph_node **order)
+{
+	return cgraph_postorder(order);
+}
+
+static inline struct cgraph_node *cgraph_create_node(tree decl)
+{
+	return cgraph_node(decl);
+}
+
+static inline struct cgraph_node *cgraph_get_create_node(tree decl)
+{
+	struct cgraph_node *node = cgraph_get_node(decl);
+
+	return node ? node : cgraph_node(decl);
+}
+
+static inline bool cgraph_function_with_gimple_body_p(struct cgraph_node *node)
+{
+	return node->analyzed && !node->thunk.thunk_p && !node->alias;
+}
+
+static inline struct cgraph_node *cgraph_first_function_with_gimple_body(void)
+{
+	struct cgraph_node *node;
+
+	for (node = cgraph_nodes; node; node = node->next)
+		if (cgraph_function_with_gimple_body_p(node))
+			return node;
+	return NULL;
+}
+
+static inline struct cgraph_node *cgraph_next_function_with_gimple_body(struct cgraph_node *node)
+{
+	for (node = node->next; node; node = node->next)
+		if (cgraph_function_with_gimple_body_p(node))
+			return node;
+	return NULL;
+}
+
+#define FOR_EACH_FUNCTION_WITH_GIMPLE_BODY(node) \
+	for ((node) = cgraph_first_function_with_gimple_body(); (node); \
+		(node) = cgraph_next_function_with_gimple_body(node))
+
+static inline void varpool_add_new_variable(tree decl)
+{
+	varpool_finalize_decl(decl);
+}
+#endif
+
+#if BUILDING_GCC_VERSION <= 4007
+#define FOR_EACH_FUNCTION(node)	\
+	for (node = cgraph_nodes; node; node = node->next)
+#define FOR_EACH_VARIABLE(node)	\
+	for (node = varpool_nodes; node; node = node->next)
+#define PROP_loops 0
+#define NODE_SYMBOL(node) (node)
+#define NODE_DECL(node) (node)->decl
+#define INSN_LOCATION(INSN) RTL_LOCATION(INSN)
+#define vNULL NULL
+
+static inline int bb_loop_depth(const_basic_block bb)
+{
+	return bb->loop_father ? loop_depth(bb->loop_father) : 0;
+}
+
+static inline bool gimple_store_p(gimple gs)
+{
+	tree lhs = gimple_get_lhs(gs);
+
+	return lhs && !is_gimple_reg(lhs);
+}
+
+static inline void gimple_init_singleton(gimple g __unused)
+{
+}
+#endif
+
+#if BUILDING_GCC_VERSION == 4007 || BUILDING_GCC_VERSION == 4008
+static inline struct cgraph_node *cgraph_alias_target(struct cgraph_node *n)
+{
+	return cgraph_alias_aliased_node(n);
+}
+#endif
+
+#if BUILDING_GCC_VERSION >= 4007 && BUILDING_GCC_VERSION <= 4009
+#define cgraph_create_edge(caller, callee, call_stmt, count, freq, nest) \
+	cgraph_create_edge((caller), (callee), (call_stmt), (count), (freq))
+#define cgraph_create_edge_including_clones(caller, callee, old_call_stmt, call_stmt, count, freq, nest, reason) \
+	cgraph_create_edge_including_clones((caller), (callee), (old_call_stmt), (call_stmt), (count), (freq), (reason))
+#endif
+
+#if BUILDING_GCC_VERSION <= 4008
+#define ENTRY_BLOCK_PTR_FOR_FN(FN)	ENTRY_BLOCK_PTR_FOR_FUNCTION(FN)
+#define EXIT_BLOCK_PTR_FOR_FN(FN)	EXIT_BLOCK_PTR_FOR_FUNCTION(FN)
+#define basic_block_info_for_fn(FN)	((FN)->cfg->x_basic_block_info)
+#define n_basic_blocks_for_fn(FN)	((FN)->cfg->x_n_basic_blocks)
+#define n_edges_for_fn(FN)		((FN)->cfg->x_n_edges)
+#define last_basic_block_for_fn(FN)	((FN)->cfg->x_last_basic_block)
+#define label_to_block_map_for_fn(FN)	((FN)->cfg->x_label_to_block_map)
+#define profile_status_for_fn(FN)	((FN)->cfg->x_profile_status)
+#define BASIC_BLOCK_FOR_FN(FN, N)	BASIC_BLOCK_FOR_FUNCTION((FN), (N))
+#define NODE_IMPLICIT_ALIAS(node)	(node)->same_body_alias
+#define VAR_P(NODE)			(TREE_CODE(NODE) == VAR_DECL)
+
+static inline bool tree_fits_shwi_p(const_tree t)
+{
+	if (t == NULL_TREE || TREE_CODE(t) != INTEGER_CST)
+		return false;
+
+	if (TREE_INT_CST_HIGH(t) == 0 && (HOST_WIDE_INT)TREE_INT_CST_LOW(t) >= 0)
+		return true;
+
+	if (TREE_INT_CST_HIGH(t) == -1 && (HOST_WIDE_INT)TREE_INT_CST_LOW(t) < 0 && !TYPE_UNSIGNED(TREE_TYPE(t)))
+		return true;
+
+	return false;
+}
+
+static inline bool tree_fits_uhwi_p(const_tree t)
+{
+	if (t == NULL_TREE || TREE_CODE(t) != INTEGER_CST)
+		return false;
+
+	return TREE_INT_CST_HIGH(t) == 0;
+}
+
+static inline HOST_WIDE_INT tree_to_shwi(const_tree t)
+{
+	gcc_assert(tree_fits_shwi_p(t));
+	return TREE_INT_CST_LOW(t);
+}
+
+static inline unsigned HOST_WIDE_INT tree_to_uhwi(const_tree t)
+{
+	gcc_assert(tree_fits_uhwi_p(t));
+	return TREE_INT_CST_LOW(t);
+}
+
+static inline const char *get_tree_code_name(enum tree_code code)
+{
+	gcc_assert(code < MAX_TREE_CODES);
+	return tree_code_name[code];
+}
+
+#define ipa_remove_stmt_references(cnode, stmt)
+
+typedef union gimple_statement_d gasm;
+typedef union gimple_statement_d gassign;
+typedef union gimple_statement_d gcall;
+typedef union gimple_statement_d gcond;
+typedef union gimple_statement_d gdebug;
+typedef union gimple_statement_d gphi;
+typedef union gimple_statement_d greturn;
+
+static inline gasm *as_a_gasm(gimple stmt)
+{
+	return stmt;
+}
+
+static inline const gasm *as_a_const_gasm(const_gimple stmt)
+{
+	return stmt;
+}
+
+static inline gassign *as_a_gassign(gimple stmt)
+{
+	return stmt;
+}
+
+static inline const gassign *as_a_const_gassign(const_gimple stmt)
+{
+	return stmt;
+}
+
+static inline gcall *as_a_gcall(gimple stmt)
+{
+	return stmt;
+}
+
+static inline const gcall *as_a_const_gcall(const_gimple stmt)
+{
+	return stmt;
+}
+
+static inline gcond *as_a_gcond(gimple stmt)
+{
+	return stmt;
+}
+
+static inline const gcond *as_a_const_gcond(const_gimple stmt)
+{
+	return stmt;
+}
+
+static inline gdebug *as_a_gdebug(gimple stmt)
+{
+	return stmt;
+}
+
+static inline const gdebug *as_a_const_gdebug(const_gimple stmt)
+{
+	return stmt;
+}
+
+static inline gphi *as_a_gphi(gimple stmt)
+{
+	return stmt;
+}
+
+static inline const gphi *as_a_const_gphi(const_gimple stmt)
+{
+	return stmt;
+}
+
+static inline greturn *as_a_greturn(gimple stmt)
+{
+	return stmt;
+}
+
+static inline const greturn *as_a_const_greturn(const_gimple stmt)
+{
+	return stmt;
+}
+#endif
+
+#if BUILDING_GCC_VERSION == 4008
+#define NODE_SYMBOL(node) (&(node)->symbol)
+#define NODE_DECL(node) (node)->symbol.decl
+#endif
+
+#if BUILDING_GCC_VERSION >= 4008
+#define add_referenced_var(var)
+#define mark_sym_for_renaming(var)
+#define varpool_mark_needed_node(node)
+#define create_var_ann(var)
+#define TODO_dump_func 0
+#define TODO_dump_cgraph 0
+#endif
+
+#if BUILDING_GCC_VERSION <= 4009
+#define TODO_verify_il 0
+#define AVAIL_INTERPOSABLE AVAIL_OVERWRITABLE
+
+#define section_name_prefix LTO_SECTION_NAME_PREFIX
+#define fatal_error(loc, gmsgid, ...) fatal_error((gmsgid), __VA_ARGS__)
+
+typedef struct rtx_def rtx_insn;
+
+static inline void set_decl_section_name(tree node, const char *value)
+{
+	if (value)
+		DECL_SECTION_NAME(node) = build_string(strlen(value) + 1, value);
+	else
+		DECL_SECTION_NAME(node) = NULL;
+}
+#endif
+
+#if BUILDING_GCC_VERSION == 4009
+typedef struct gimple_statement_asm gasm;
+typedef struct gimple_statement_base gassign;
+typedef struct gimple_statement_call gcall;
+typedef struct gimple_statement_base gcond;
+typedef struct gimple_statement_base gdebug;
+typedef struct gimple_statement_phi gphi;
+typedef struct gimple_statement_base greturn;
+
+static inline gasm *as_a_gasm(gimple stmt)
+{
+	return as_a<gasm>(stmt);
+}
+
+static inline const gasm *as_a_const_gasm(const_gimple stmt)
+{
+	return as_a<const gasm>(stmt);
+}
+
+static inline gassign *as_a_gassign(gimple stmt)
+{
+	return stmt;
+}
+
+static inline const gassign *as_a_const_gassign(const_gimple stmt)
+{
+	return stmt;
+}
+
+static inline gcall *as_a_gcall(gimple stmt)
+{
+	return as_a<gcall>(stmt);
+}
+
+static inline const gcall *as_a_const_gcall(const_gimple stmt)
+{
+	return as_a<const gcall>(stmt);
+}
+
+static inline gcond *as_a_gcond(gimple stmt)
+{
+	return stmt;
+}
+
+static inline const gcond *as_a_const_gcond(const_gimple stmt)
+{
+	return stmt;
+}
+
+static inline gdebug *as_a_gdebug(gimple stmt)
+{
+	return stmt;
+}
+
+static inline const gdebug *as_a_const_gdebug(const_gimple stmt)
+{
+	return stmt;
+}
+
+static inline gphi *as_a_gphi(gimple stmt)
+{
+	return as_a<gphi>(stmt);
+}
+
+static inline const gphi *as_a_const_gphi(const_gimple stmt)
+{
+	return as_a<const gphi>(stmt);
+}
+
+static inline greturn *as_a_greturn(gimple stmt)
+{
+	return stmt;
+}
+
+static inline const greturn *as_a_const_greturn(const_gimple stmt)
+{
+	return stmt;
+}
+#endif
+
+#if BUILDING_GCC_VERSION >= 4009
+#define TODO_ggc_collect 0
+#define NODE_SYMBOL(node) (node)
+#define NODE_DECL(node) (node)->decl
+#define cgraph_node_name(node) (node)->name()
+#define NODE_IMPLICIT_ALIAS(node) (node)->cpp_implicit_alias
+#endif
+
+#if BUILDING_GCC_VERSION >= 5000 && BUILDING_GCC_VERSION < 6000
+/* gimple related */
+template <>
+template <>
+inline bool is_a_helper<const gassign *>::test(const_gimple gs)
+{
+	return gs->code == GIMPLE_ASSIGN;
+}
+#endif
+
+#if BUILDING_GCC_VERSION >= 5000
+#define TODO_verify_ssa TODO_verify_il
+#define TODO_verify_flow TODO_verify_il
+#define TODO_verify_stmts TODO_verify_il
+#define TODO_verify_rtl_sharing TODO_verify_il
+
+#define INSN_DELETED_P(insn) (insn)->deleted()
+
+/* symtab/cgraph related */
+#define debug_cgraph_node(node) (node)->debug()
+#define cgraph_get_node(decl) cgraph_node::get(decl)
+#define cgraph_get_create_node(decl) cgraph_node::get_create(decl)
+#define cgraph_create_node(decl) cgraph_node::create(decl)
+#define cgraph_n_nodes symtab->cgraph_count
+#define cgraph_max_uid symtab->cgraph_max_uid
+#define varpool_get_node(decl) varpool_node::get(decl)
+
+#define cgraph_create_edge(caller, callee, call_stmt, count, freq, nest) \
+	(caller)->create_edge((callee), (call_stmt), (count), (freq))
+#define cgraph_create_edge_including_clones(caller, callee, old_call_stmt, call_stmt, count, freq, nest, reason) \
+	(caller)->create_edge_including_clones((callee), (old_call_stmt), (call_stmt), (count), (freq), (reason))
+
+typedef struct cgraph_node *cgraph_node_ptr;
+typedef struct cgraph_edge *cgraph_edge_p;
+typedef struct varpool_node *varpool_node_ptr;
+
+static inline void change_decl_assembler_name(tree decl, tree name)
+{
+	symtab->change_decl_assembler_name(decl, name);
+}
+
+static inline void varpool_finalize_decl(tree decl)
+{
+	varpool_node::finalize_decl(decl);
+}
+
+static inline void varpool_add_new_variable(tree decl)
+{
+	varpool_node::add(decl);
+}
+
+static inline unsigned int rebuild_cgraph_edges(void)
+{
+	return cgraph_edge::rebuild_edges();
+}
+
+static inline cgraph_node_ptr cgraph_function_node(cgraph_node_ptr node, enum availability *availability)
+{
+	return node->function_symbol(availability);
+}
+
+static inline cgraph_node_ptr cgraph_function_or_thunk_node(cgraph_node_ptr node, enum availability *availability = NULL)
+{
+	return node->ultimate_alias_target(availability);
+}
+
+static inline bool cgraph_only_called_directly_p(cgraph_node_ptr node)
+{
+	return node->only_called_directly_p();
+}
+
+static inline enum availability cgraph_function_body_availability(cgraph_node_ptr node)
+{
+	return node->get_availability();
+}
+
+static inline cgraph_node_ptr cgraph_alias_target(cgraph_node_ptr node)
+{
+	return node->get_alias_target();
+}
+
+static inline struct cgraph_node_hook_list *cgraph_add_function_insertion_hook(cgraph_node_hook hook, void *data)
+{
+	return symtab->add_cgraph_insertion_hook(hook, data);
+}
+
+static inline void cgraph_remove_function_insertion_hook(struct cgraph_node_hook_list *entry)
+{
+	symtab->remove_cgraph_insertion_hook(entry);
+}
+
+static inline struct cgraph_node_hook_list *cgraph_add_node_removal_hook(cgraph_node_hook hook, void *data)
+{
+	return symtab->add_cgraph_removal_hook(hook, data);
+}
+
+static inline void cgraph_remove_node_removal_hook(struct cgraph_node_hook_list *entry)
+{
+	symtab->remove_cgraph_removal_hook(entry);
+}
+
+static inline struct cgraph_2node_hook_list *cgraph_add_node_duplication_hook(cgraph_2node_hook hook, void *data)
+{
+	return symtab->add_cgraph_duplication_hook(hook, data);
+}
+
+static inline void cgraph_remove_node_duplication_hook(struct cgraph_2node_hook_list *entry)
+{
+	symtab->remove_cgraph_duplication_hook(entry);
+}
+
+static inline void cgraph_call_node_duplication_hooks(cgraph_node_ptr node, cgraph_node_ptr node2)
+{
+	symtab->call_cgraph_duplication_hooks(node, node2);
+}
+
+static inline void cgraph_call_edge_duplication_hooks(cgraph_edge *cs1, cgraph_edge *cs2)
+{
+	symtab->call_edge_duplication_hooks(cs1, cs2);
+}
+
+#if BUILDING_GCC_VERSION >= 6000
+typedef gimple *gimple_ptr;
+typedef const gimple *const_gimple_ptr;
+#define gimple gimple_ptr
+#define const_gimple const_gimple_ptr
+#undef CONST_CAST_GIMPLE
+#define CONST_CAST_GIMPLE(X) CONST_CAST(gimple, (X))
+#endif
+
+/* gimple related */
+static inline gimple gimple_build_assign_with_ops(enum tree_code subcode, tree lhs, tree op1, tree op2 MEM_STAT_DECL)
+{
+	return gimple_build_assign(lhs, subcode, op1, op2 PASS_MEM_STAT);
+}
+
+template <>
+template <>
+inline bool is_a_helper<const greturn *>::test(const_gimple gs)
+{
+	return gs->code == GIMPLE_RETURN;
+}
+
+static inline gasm *as_a_gasm(gimple stmt)
+{
+	return as_a<gasm *>(stmt);
+}
+
+static inline const gasm *as_a_const_gasm(const_gimple stmt)
+{
+	return as_a<const gasm *>(stmt);
+}
+
+static inline gassign *as_a_gassign(gimple stmt)
+{
+	return as_a<gassign *>(stmt);
+}
+
+static inline const gassign *as_a_const_gassign(const_gimple stmt)
+{
+	return as_a<const gassign *>(stmt);
+}
+
+static inline gcall *as_a_gcall(gimple stmt)
+{
+	return as_a<gcall *>(stmt);
+}
+
+static inline const gcall *as_a_const_gcall(const_gimple stmt)
+{
+	return as_a<const gcall *>(stmt);
+}
+
+static inline gphi *as_a_gphi(gimple stmt)
+{
+	return as_a<gphi *>(stmt);
+}
+
+static inline const gphi *as_a_const_gphi(const_gimple stmt)
+{
+	return as_a<const gphi *>(stmt);
+}
+
+static inline greturn *as_a_greturn(gimple stmt)
+{
+	return as_a<greturn *>(stmt);
+}
+
+static inline const greturn *as_a_const_greturn(const_gimple stmt)
+{
+	return as_a<const greturn *>(stmt);
+}
+
+/* IPA/LTO related */
+#define ipa_ref_list_referring_iterate(L, I, P)	\
+	(L)->referring.iterate((I), &(P))
+#define ipa_ref_list_reference_iterate(L, I, P)	\
+	(L)->reference.iterate((I), &(P))
+
+static inline cgraph_node_ptr ipa_ref_referring_node(struct ipa_ref *ref)
+{
+	return dyn_cast<cgraph_node_ptr>(ref->referring);
+}
+
+static inline void ipa_remove_stmt_references(symtab_node *referring_node, gimple stmt)
+{
+	referring_node->remove_stmt_references(stmt);
+}
+#endif
+
+#if BUILDING_GCC_VERSION < 6000
+#define get_inner_reference(exp, pbitsize, pbitpos, poffset, pmode, punsignedp, preversep, pvolatilep, keep_aligning)	\
+	get_inner_reference(exp, pbitsize, pbitpos, poffset, pmode, punsignedp, pvolatilep, keep_aligning)
+#define gen_rtx_set(ARG0, ARG1) gen_rtx_SET(VOIDmode, (ARG0), (ARG1))
+#endif
+
+#if BUILDING_GCC_VERSION >= 6000
+#define gen_rtx_set(ARG0, ARG1) gen_rtx_SET((ARG0), (ARG1))
+#endif
+
+#ifdef __cplusplus
+static inline void debug_tree(const_tree t)
+{
+	debug_tree(CONST_CAST_TREE(t));
+}
+
+static inline void debug_gimple_stmt(const_gimple s)
+{
+	debug_gimple_stmt(CONST_CAST_GIMPLE(s));
+}
+#else
+#define debug_tree(t) debug_tree(CONST_CAST_TREE(t))
+#define debug_gimple_stmt(s) debug_gimple_stmt(CONST_CAST_GIMPLE(s))
+#endif
+
+#endif