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>

22 files changed, 1872 insertions, 5 deletions

diff --git a/.gitignore b/.gitignore
index 0c320bf02586..2be25f771bd8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -37,6 +37,7 @@ modules.builtin
 Module.symvers
 *.dwo
 *.su
+*.c.[012]*.*
 
 #
 # Top-level generic files
diff --git a/Documentation/dontdiff b/Documentation/dontdiff
index 8ea834f6b289..5385cba941d2 100644
--- a/Documentation/dontdiff
+++ b/Documentation/dontdiff
@@ -3,6 +3,7 @@
 *.bc
 *.bin
 *.bz2
+*.c.[012]*.*
 *.cis
 *.cpio
 *.csp
diff --git a/Documentation/gcc-plugins.txt b/Documentation/gcc-plugins.txt
new file mode 100644
index 000000000000..891c69464434
--- /dev/null
+++ b/Documentation/gcc-plugins.txt
@@ -0,0 +1,87 @@
+GCC plugin infrastructure
+=========================
+
+
+1. Introduction
+===============
+
+GCC plugins are loadable modules that provide extra features to the
+compiler [1]. They are useful for runtime instrumentation and static analysis.
+We can analyse, change and add further code during compilation via
+callbacks [2], GIMPLE [3], IPA [4] and RTL passes [5].
+
+The GCC plugin infrastructure of the kernel supports all gcc versions from
+4.5 to 6.0, building out-of-tree modules, cross-compilation and building in a
+separate directory.
+Plugin source files have to be compilable by both a C and a C++ compiler as well
+because gcc versions 4.5 and 4.6 are compiled by a C compiler,
+gcc-4.7 can be compiled by a C or a C++ compiler,
+and versions 4.8+ can only be compiled by a C++ compiler.
+
+Currently the GCC plugin infrastructure supports only the x86, arm and arm64
+architectures.
+
+This infrastructure was ported from grsecurity [6] and PaX [7].
+
+--
+[1] https://gcc.gnu.org/onlinedocs/gccint/Plugins.html
+[2] https://gcc.gnu.org/onlinedocs/gccint/Plugin-API.html#Plugin-API
+[3] https://gcc.gnu.org/onlinedocs/gccint/GIMPLE.html
+[4] https://gcc.gnu.org/onlinedocs/gccint/IPA.html
+[5] https://gcc.gnu.org/onlinedocs/gccint/RTL.html
+[6] https://grsecurity.net/
+[7] https://pax.grsecurity.net/
+
+
+2. Files
+========
+
+$(src)/scripts/gcc-plugins
+	This is the directory of the GCC plugins.
+
+$(src)/scripts/gcc-plugins/gcc-common.h
+	This is a compatibility header for GCC plugins.
+	It should be always included instead of individual gcc headers.
+
+$(src)/scripts/gcc-plugin.sh
+	This script checks the availability of the included headers in
+	gcc-common.h and chooses the proper host compiler to build the plugins
+	(gcc-4.7 can be built by either gcc or g++).
+
+$(src)/scripts/gcc-plugins/gcc-generate-gimple-pass.h
+$(src)/scripts/gcc-plugins/gcc-generate-ipa-pass.h
+$(src)/scripts/gcc-plugins/gcc-generate-simple_ipa-pass.h
+$(src)/scripts/gcc-plugins/gcc-generate-rtl-pass.h
+	These headers automatically generate the registration structures for
+	GIMPLE, SIMPLE_IPA, IPA and RTL passes. They support all gcc versions
+	from 4.5 to 6.0.
+	They should be preferred to creating the structures by hand.
+
+
+3. Usage
+========
+
+You must install the gcc plugin headers for your gcc version,
+e.g., on Ubuntu for gcc-4.9:
+
+	apt-get install gcc-4.9-plugin-dev
+
+Enable a GCC plugin based feature in the kernel config:
+
+	CONFIG_GCC_PLUGIN_CYC_COMPLEXITY = y
+
+To compile only the plugin(s):
+
+	make gcc-plugins
+
+or just run the kernel make and compile the whole kernel with
+the cyclomatic complexity GCC plugin.
+
+
+4. How to add a new GCC plugin
+==============================
+
+The GCC plugins are in $(src)/scripts/gcc-plugins/. You can use a file or a directory
+here. It must be added to $(src)/scripts/gcc-plugins/Makefile,
+$(src)/scripts/Makefile.gcc-plugins and $(src)/arch/Kconfig.
+See the cyc_complexity_plugin.c (CONFIG_GCC_PLUGIN_CYC_COMPLEXITY) GCC plugin.
diff --git a/MAINTAINERS b/MAINTAINERS
index 7304d2e37a98..94a19add522d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4979,6 +4979,15 @@ L:	linux-scsi@vger.kernel.org
 S:	Odd Fixes (e.g., new signatures)
 F:	drivers/scsi/fdomain.*
 
+GCC PLUGINS
+M:	Kees Cook <keescook@chromium.org>
+R:	Emese Revfy <re.emese@gmail.com>
+L:	kernel-hardening@lists.openwall.com
+S:	Maintained
+F:	scripts/gcc-plugins/
+F:	scripts/gcc-plugin.sh
+F:	Documentation/gcc-plugins.txt
+
 GCOV BASED KERNEL PROFILING
 M:	Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
 S:	Maintained
diff --git a/Makefile b/Makefile
index 0f70de63cfdb..20fcf4b26fbc 100644
--- a/Makefile
+++ b/Makefile
@@ -552,7 +552,7 @@ ifeq ($(KBUILD_EXTMOD),)
 # in parallel
 PHONY += scripts
 scripts: scripts_basic include/config/auto.conf include/config/tristate.conf \
-	 asm-generic
+	 asm-generic gcc-plugins
 	$(Q)$(MAKE) $(build)=$(@)
 
 # Objects we will link into vmlinux / subdirs we need to visit
@@ -631,6 +631,15 @@ endif
 # Tell gcc to never replace conditional load with a non-conditional one
 KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
 
+PHONY += gcc-plugins
+gcc-plugins: scripts_basic
+ifdef CONFIG_GCC_PLUGINS
+	$(Q)$(MAKE) $(build)=scripts/gcc-plugins
+endif
+	@:
+
+include scripts/Makefile.gcc-plugins
+
 ifdef CONFIG_READABLE_ASM
 # Disable optimizations that make assembler listings hard to read.
 # reorder blocks reorders the control in the function
@@ -1026,7 +1035,7 @@ prepare1: prepare2 $(version_h) include/generated/utsrelease.h \
 
 archprepare: archheaders archscripts prepare1 scripts_basic
 
-prepare0: archprepare
+prepare0: archprepare gcc-plugins
 	$(Q)$(MAKE) $(build)=.
 
 # All the preparing..
@@ -1507,6 +1516,7 @@ clean: $(clean-dirs)
 		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
 		-o -name '*.symtypes' -o -name 'modules.order' \
 		-o -name modules.builtin -o -name '.tmp_*.o.*' \
+		-o -name '*.c.[012]*.*' \
 		-o -name '*.gcno' \) -type f -print | xargs rm -f
 
 # Generate tags for editors
diff --git a/arch/Kconfig b/arch/Kconfig
index d794384a0404..1b93632198fa 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -357,6 +357,21 @@ config SECCOMP_FILTER
 
 	  See Documentation/prctl/seccomp_filter.txt for details.
 
+config HAVE_GCC_PLUGINS
+	bool
+	help
+	  An arch should select this symbol if it supports building with
+	  GCC plugins.
+
+menuconfig GCC_PLUGINS
+	bool "GCC plugins"
+	depends on HAVE_GCC_PLUGINS
+	help
+	  GCC plugins are loadable modules that provide extra features to the
+	  compiler. They are useful for runtime instrumentation and static analysis.
+
+	  See Documentation/gcc-plugins.txt for details.
+
 config HAVE_CC_STACKPROTECTOR
 	bool
 	help
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 90542db1220d..ce590468ffa2 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -54,6 +54,7 @@ config ARM
 	select HAVE_FTRACE_MCOUNT_RECORD if (!XIP_KERNEL)
 	select HAVE_FUNCTION_GRAPH_TRACER if (!THUMB2_KERNEL)
 	select HAVE_FUNCTION_TRACER if (!XIP_KERNEL)
+	select HAVE_GCC_PLUGINS
 	select HAVE_GENERIC_DMA_COHERENT
 	select HAVE_HW_BREAKPOINT if (PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7))
 	select HAVE_IDE if PCI || ISA || PCMCIA
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 76747d92bc72..24e7bd6778ea 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -76,6 +76,7 @@ config ARM64
 	select HAVE_FTRACE_MCOUNT_RECORD
 	select HAVE_FUNCTION_TRACER
 	select HAVE_FUNCTION_GRAPH_TRACER
+	select HAVE_GCC_PLUGINS
 	select HAVE_GENERIC_DMA_COHERENT
 	select HAVE_HW_BREAKPOINT if PERF_EVENTS
 	select HAVE_IRQ_TIME_ACCOUNTING
diff --git a/arch/um/Kconfig.common b/arch/um/Kconfig.common
index cc0013475444..58650d098fb4 100644
--- a/arch/um/Kconfig.common
+++ b/arch/um/Kconfig.common
@@ -9,6 +9,7 @@ config UML
 	select GENERIC_CPU_DEVICES
 	select GENERIC_IO
 	select GENERIC_CLOCKEVENTS
+	select HAVE_GCC_PLUGINS
 	select TTY # Needed for line.c
 
 config MMU
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 0a7b885964ba..65e7701bd429 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -111,6 +111,7 @@ config X86
 	select HAVE_FUNCTION_GRAPH_FP_TEST
 	select HAVE_FUNCTION_GRAPH_TRACER
 	select HAVE_FUNCTION_TRACER
+	select HAVE_GCC_PLUGINS
 	select HAVE_GENERIC_DMA_COHERENT	if X86_32
 	select HAVE_HW_BREAKPOINT
 	select HAVE_IDE
diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile
index 253b72eaade6..f9123163a850 100644
--- a/arch/x86/entry/vdso/Makefile
+++ b/arch/x86/entry/vdso/Makefile
@@ -75,7 +75,7 @@ CFL := $(PROFILING) -mcmodel=small -fPIC -O2 -fasynchronous-unwind-tables -m64 \
        -fno-omit-frame-pointer -foptimize-sibling-calls \
        -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO
 
-$(vobjs): KBUILD_CFLAGS += $(CFL)
+$(vobjs): KBUILD_CFLAGS := $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS)) $(CFL)
 
 #
 # vDSO code runs in userspace and -pg doesn't help with profiling anyway.
@@ -145,6 +145,7 @@ KBUILD_CFLAGS_32 := $(filter-out -m64,$(KBUILD_CFLAGS))
 KBUILD_CFLAGS_32 := $(filter-out -mcmodel=kernel,$(KBUILD_CFLAGS_32))
 KBUILD_CFLAGS_32 := $(filter-out -fno-pic,$(KBUILD_CFLAGS_32))
 KBUILD_CFLAGS_32 := $(filter-out -mfentry,$(KBUILD_CFLAGS_32))
+KBUILD_CFLAGS_32 := $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS_32))
 KBUILD_CFLAGS_32 += -m32 -msoft-float -mregparm=0 -fpic
 KBUILD_CFLAGS_32 += $(call cc-option, -fno-stack-protector)
 KBUILD_CFLAGS_32 += $(call cc-option, -foptimize-sibling-calls)
diff --git a/scripts/Makefile b/scripts/Makefile
index 822ab4a6a4aa..1d80897a9644 100644
--- a/scripts/Makefile
+++ b/scripts/Makefile
@@ -47,4 +47,4 @@ subdir-$(CONFIG_DTC)         += dtc
 subdir-$(CONFIG_GDB_SCRIPTS) += gdb
 
 # Let clean descend into subdirs
-subdir-	+= basic kconfig package
+subdir-	+= basic kconfig package gcc-plugins
diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins
new file mode 100644
index 000000000000..bcc373dcb3b5
--- /dev/null
+++ b/scripts/Makefile.gcc-plugins
@@ -0,0 +1,23 @@
+ifdef CONFIG_GCC_PLUGINS
+  __PLUGINCC := $(call cc-ifversion, -ge, 0408, $(HOSTCXX), $(HOSTCC))
+  PLUGINCC := $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-plugin.sh "$(__PLUGINCC)" "$(HOSTCXX)" "$(CC)")
+
+  GCC_PLUGINS_CFLAGS := $(addprefix -fplugin=$(objtree)/scripts/gcc-plugins/, $(gcc-plugin-y))
+
+  export PLUGINCC GCC_PLUGINS_CFLAGS GCC_PLUGIN
+
+  ifeq ($(PLUGINCC),)
+    ifneq ($(GCC_PLUGINS_CFLAGS),)
+      ifeq ($(call cc-ifversion, -ge, 0405, y), y)
+        PLUGINCC := $(shell $(CONFIG_SHELL) -x $(srctree)/scripts/gcc-plugin.sh "$(__PLUGINCC)" "$(HOSTCXX)" "$(CC)")
+        $(warning warning: your gcc installation does not support plugins, perhaps the necessary headers are missing?)
+      else
+        $(warning warning: your gcc version does not support plugins, you should upgrade it to gcc 4.5 at least)
+      endif
+    endif
+  endif
+
+  KBUILD_CFLAGS += $(GCC_PLUGINS_CFLAGS)
+  GCC_PLUGIN := $(gcc-plugin-y)
+
+endif
diff --git a/scripts/gcc-plugin.sh b/scripts/gcc-plugin.sh
new file mode 100755
index 000000000000..fb9207565471
--- /dev/null
+++ b/scripts/gcc-plugin.sh
@@ -0,0 +1,51 @@
+#!/bin/sh
+srctree=$(dirname "$0")
+gccplugins_dir=$($3 -print-file-name=plugin)
+plugincc=$($1 -E -x c++ - -o /dev/null -I"${srctree}"/gcc-plugins -I"${gccplugins_dir}"/include 2>&1 <<EOF
+#include "gcc-common.h"
+#if BUILDING_GCC_VERSION >= 4008 || defined(ENABLE_BUILD_WITH_CXX)
+#warning $2 CXX
+#else
+#warning $1 CC
+#endif
+EOF
+)
+
+if [ $? -ne 0 ]
+then
+	exit 1
+fi
+
+case "$plugincc" in
+	*"$1 CC"*)
+		echo "$1"
+		exit 0
+		;;
+
+	*"$2 CXX"*)
+		# the c++ compiler needs another test, see below
+		;;
+
+	*)
+		exit 1
+		;;
+esac
+
+# we need a c++ compiler that supports the designated initializer GNU extension
+plugincc=$($2 -c -x c++ -std=gnu++98 - -fsyntax-only -I"${srctree}"/gcc-plugins -I"${gccplugins_dir}"/include 2>&1 <<EOF
+#include "gcc-common.h"
+class test {
+public:
+	int test;
+} test = {
+	.test = 1
+};
+EOF
+)
+
+if [ $? -eq 0 ]
+then
+	echo "$2"
+	exit 0
+fi
+exit 1
diff --git a/scripts/gcc-plugins/Makefile b/scripts/gcc-plugins/Makefile
new file mode 100644
index 000000000000..a4c93419d5d1
--- /dev/null
+++ b/scripts/gcc-plugins/Makefile
@@ -0,0 +1,20 @@
+GCC_PLUGINS_DIR := $(shell $(CC) -print-file-name=plugin)
+
+ifeq ($(PLUGINCC),$(HOSTCC))
+  HOSTLIBS := hostlibs
+  HOST_EXTRACFLAGS += -I$(GCC_PLUGINS_DIR)/include -I$(src) -std=gnu99 -ggdb
+  export HOST_EXTRACFLAGS
+else
+  HOSTLIBS := hostcxxlibs
+  HOST_EXTRACXXFLAGS += -I$(GCC_PLUGINS_DIR)/include -I$(src) -std=gnu++98 -fno-rtti
+  HOST_EXTRACXXFLAGS += -fno-exceptions -fasynchronous-unwind-tables -ggdb
+  HOST_EXTRACXXFLAGS += -Wno-narrowing -Wno-unused-variable
+  export HOST_EXTRACXXFLAGS
+endif
+
+export GCCPLUGINS_DIR HOSTLIBS
+
+$(HOSTLIBS)-y := $(GCC_PLUGIN)
+always := $($(HOSTLIBS)-y)
+
+clean-files += *.so
diff --git a/scripts/gcc-plugins/gcc-common.h b/scripts/gcc-plugins/gcc-common.h
new file mode 100644
index 000000000000..172850bcd0d9
--- /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)