make/cpp2asm_support.cmake - external/dynamorio - Git at Google

 # **********************************************************
 # Copyright (c) 2010-2014 Google, Inc.    All rights reserved.
 # Copyright (c) 2009-2010 VMware, Inc.    All rights reserved.
 # **********************************************************

 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are met:
 #
 # * Redistributions of source code must retain the above copyright notice,
 #   this list of conditions and the following disclaimer.
 #
 # * Redistributions in binary form must reproduce the above copyright notice,
 #   this list of conditions and the following disclaimer in the documentation
 #   and/or other materials provided with the distribution.
 #
 # * Neither the name of VMware, Inc. nor the names of its contributors may be
 #   used to endorse or promote products derived from this software without
 #   specific prior written permission.
 #
 # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 # ARE DISCLAIMED. IN NO EVENT SHALL VMWARE, INC. OR CONTRIBUTORS BE LIABLE
 # FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 # SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 # CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 # LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 # OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
 # DAMAGE.

 ###########################################################################
 # Enhanced assembly support for CMake projects
 #
 # Features:
 # + Cmake support for asm with Makefiles and Visual Studio.
 # + Cross-platform asm using Intel syntax and C pre-processor
 #   to feed to assembler.
 # + Asm code in C/C++ files (separated via #ifdef ASM_CODE_ONLY) to avoid
 #   needing standalone assembly files with 64-bit cl.
 #
 ###################################################
 # Usage:
 #
 # Setup:
 # + Place both this file and cpp2asm_add_newlines.cmake in the same
 #   directory (or, point at cpp2asm_add_newlines.cmake with the
 #   variable ${cpp2asm_newline_script_path}).
 # + Include this file in your CMakeLists.txt file.
 # + For UNIX, the available assembler may not support Intel syntex.
 #   In that case, CMAKE_ASM_SUPPORTS_INTEL_SYNTAX will be set to false.
 #   The includer of this file can decide whether that's a fatal error.
 #
 # Example setup:
 #   include(cpp2asm_support.cmake)
 #   if (UNIX)
 #     if (NOT CMAKE_ASM_SUPPORTS_INTEL_SYNTAX)
 #       <either FATAL_ERROR or point CMAKE_ASM_COMPILER at a gas binary to use>
 #     endif ()
 #   endif (UNIX)
 #
 # Assembly file:
 # + Write assembly using Intel syntax and the macros in the
 #   cpp2asm_defines.h file included in this directory.
 # + Before #include of cpp2asm_defines.h in your asm file, define
 #   one of ASSEMBLE_WITH_{GAS,MASM,NASM}
 # + cpp2asm_defines.h is not automatically added as a dependence.
 #   If you are using it, pass in its path as part of the extra_deps option.
 # + cpp2asm_defines.h's dir is not automatically added as an include dir.
 #   If you are using it, pass in "-I;<path>" as part of the extra_defs option.
 # + The global preprocessor defines are used for Makefile generators.
 #   For Visual Studio generators, pass in the defines needed (as a list)
 #   as part of the extra_defs option.  These extra_defs are NOT honored
 #   for Makefile generators and should be added by the caller to the
 #   target or global flags.
 # + Have assembly files #include a configure.h or other header to obtain
 #   their defines (this file does not support passing them in via cmdline
 #   to the preprocessor or the assembler).
 # + For pure assembly files, use add_asm_target(); for split C/C++ + asm files,
 #   separate the two pieces via #ifdef ASM_CODE_ONLY and use
 #   add_split_asm_target().
 # + For VS generators, add the returned target as a dependence of the final
 #   executable/library target to avoid races when building.
 #
 # Example:
 #
 #   set(asm_deps "/path/to/cpp2asm_defines.h" "/path/to/configure.h")
 #   set(asm_defs -I "/path/to/cpp2asm_defines.h" -I "/path/to/configure.h")
 #   add_asm_target(foo.asm foo_asm_src foo_asm_tgt "" "${asm_defs}" ${asm_deps})
 #   add_library(bar bar.c ${foo_asm_src})
 #   if ("${CMAKE_GENERATOR}" MATCHES "Visual Studio")
 #     add_dependencies(bar ${foo_asm_tgt})
 #   endif ("${CMAKE_GENERATOR}" MATCHES "Visual Studio")
 #
 ###########################################################################

 if ("${CMAKE_GENERATOR}" MATCHES "Visual Studio 10")
   # For i#801 workaround
   cmake_minimum_required(VERSION 2.8.8)
 else ()
   if (APPLE)
     # We want ASM NASM support
     cmake_minimum_required(VERSION 2.8.3)
   else (APPLE)
     # Require 2.6.4 to avoid cmake bug #8639, unless this var is
     # properly set (which it is for DR b/c it has a workaround):
     if (NOT "${CMAKE_ASM_SOURCE_FILE_EXTENSIONS}" MATCHES "asm")
       cmake_minimum_required(VERSION 2.6.4)
     endif ()
   endif (APPLE)
 endif ()

 ##################################################
 # Helper files

 if (NOT cpp2asm_newline_script_path)
   # By default we expect cpp2asm_add_newlines.cmake in same dir as this file.
   get_filename_component(my_dir "${CMAKE_CURRENT_LIST_FILE}" PATH)
   set(cpp2asm_newline_script_path "${my_dir}/cpp2asm_add_newlines.cmake")
 endif ()
 if (NOT EXISTS "${cpp2asm_newline_script_path}")
   message(FATAL_ERROR "Cannot find \"${cpp2asm_newline_script_path}\". "
     "Please set the cpp2asm_newline_script_path variable.")
 endif ()

 ##################################################
 # Preprocessor location and flags

 if (UNIX)
   # "gcc -E" on a non-.c-extension file gives message:
   #   "linker input file unused because linking not done"
   # and doesn't produce any output, so we must use cpp for our .asm files.
   # we assume it's in the same dir.
   get_filename_component(compiler_path ${CMAKE_C_COMPILER} PATH)
   find_program(CMAKE_CPP cpp HINTS "${compiler_path}" DOC "path to C preprocessor")
   if (NOT CMAKE_CPP)
     message(FATAL_ERROR "cpp is required to build")
   endif (NOT CMAKE_CPP)
   mark_as_advanced(CMAKE_CPP)

   set(CPP_KEEP_COMMENTS -C)
   set(CPP_NO_LINENUM -P)
   set(CPP_KEEP_WHITESPACE -traditional-cpp)
   set(CMAKE_CPP_FLAGS "")
 else (UNIX)
   set(CMAKE_CPP ${CMAKE_C_COMPILER})

   set(CPP_KEEP_COMMENTS /C)
   set(CPP_NO_LINENUM /EP)
   set(CPP_KEEP_WHITESPACE "")
   set(CMAKE_CPP_FLAGS "/nologo")
 endif (UNIX)

 ##################################################
 # Assembler location and flags

 if (NOT "${CMAKE_GENERATOR}" MATCHES "Visual Studio")
   if (UNIX)
     # i#646: cmake 2.8.5 requires ASM-ATT to find as: but we don't want to change
     # all our vars to have -ATT suffix so we set the search list instead.
     # This must be done prior to enable_language(ASM).
     set(CMAKE_ASM_COMPILER_INIT gas as)
   endif (UNIX)
   # CMake does not support assembly with VS generators
   # (http://public.kitware.com/Bug/view.php?id=11536)
   # so we have to add our own custom commands and targets
   if (APPLE)
     # NASM support was added in 2.8.3.  It clears ASM_DIALECT for us.
     enable_language(ASM_NASM)
   else (APPLE)
     enable_language(ASM)
   endif (APPLE)
 endif ()

 if (APPLE)
   # XXX: we may be able to avoid some of this given CMake 2.8.3's NASM support.
   find_program(NASM nasm DOC "path to nasm assembler")
   if (NOT NASM)
     message(FATAL_ERROR "nasm assembler not found: required to build")
   endif (NOT NASM)
   message(STATUS "Found nasm: ${NASM}")
   execute_process(COMMAND ${NASM} -hf OUTPUT_VARIABLE nasm_result ERROR_QUIET)
   if (X64)
     # x64 support added between 0.98.40 and 2.10.07
     if (NOT nasm_result MATCHES macho64)
       message(FATAL_ERROR "nasm is too old: no 64-bit support")
     endif ()
     set(ASM_FLAGS "${ASM_FLAGS} -fmacho64")
   else (X64)
     if (nasm_result MATCHES macho32)
       set(ASM_FLAGS "${ASM_FLAGS} -fmacho32")
     else ()
       set(ASM_FLAGS "${ASM_FLAGS} -fmacho")
     endif ()
   endif (X64)
   if (DEBUG)
     set(ASM_FLAGS "${ASM_FLAGS} -g")
   endif (DEBUG)
 elseif (UNIX)
   if (X86)
     set(ASM_FLAGS "-mmnemonic=intel -msyntax=intel -mnaked-reg")
     if (X64)
       set(ASM_FLAGS "${ASM_FLAGS} --64")
     else (X64)
       # putting --32 last so we fail on -mmnemonic=intel on older as, not --32
       set(ASM_FLAGS "${ASM_FLAGS} --32")
     endif (X64)
   elseif (ARM)
     # No 64-bit support yet so currently no flags.
   endif ()
   set(ASM_FLAGS "${ASM_FLAGS} --noexecstack")
   if (DEBUG)
     set(ASM_FLAGS "${ASM_FLAGS} -g")
   endif (DEBUG)
 else ()
   if (X64)
     find_program(CMAKE_ASM_COMPILER ml64.exe HINTS "${cl_path}" DOC "path to assembler")
   else (X64)
     find_program(CMAKE_ASM_COMPILER ml.exe HINTS "${cl_path}" DOC "path to assembler")
   endif (X64)
   if (NOT CMAKE_ASM_COMPILER)
     message(FATAL_ERROR "assembler not found: required to build")
   endif (NOT CMAKE_ASM_COMPILER)
   message(STATUS "Found assembler: ${CMAKE_ASM_COMPILER}")
   if (NOT DEFINED GENERATE_PDBS OR GENERATE_PDBS)
     set(ASM_DBG "/Zi /Zd")
   else ()
     set(ASM_DBG "")
   endif ()
   set(ASM_FLAGS "/nologo ${ASM_DBG}")
 endif ()
 string(REPLACE " " ";" ASM_FLAGS_LIST "${ASM_FLAGS}")

 if (APPLE)
   # XXX: xcode assembler uses Intel mnemonics but opposite src,dst order!
   # We rely on having nasm installed as a workaround.
   set(CMAKE_ASM_SUPPORTS_INTEL_SYNTAX ON)
 endif (APPLE)
 if (UNIX AND NOT APPLE)
   # We require gas >= 2.18.50 for --32, --64, and the new -msyntax=intel, etc.
   execute_process(COMMAND
     ${CMAKE_ASM_COMPILER} --help
     RESULT_VARIABLE asm_result
     ERROR_VARIABLE asm_error
     OUTPUT_VARIABLE asm_out)
   if (asm_result OR asm_error)
     message(FATAL_ERROR "*** ${CMAKE_ASM_COMPILER} failed: ***\n${asm_error}")
   endif (asm_result OR asm_error)
   # turn the flags into a vector
   string(REGEX REPLACE " " ";" flags_needed "${ASM_FLAGS}")
   # we want "-mmnemonic=intel" to match "-mmnemonic=[att|intel]"
   string(REGEX REPLACE "=" ".*" flags_needed "${flags_needed}")
   set(flag_present 1)
   foreach (flag ${flags_needed})
     if (flag_present)
       string(REGEX MATCH "${flag}" flag_present "${asm_out}")
       if (NOT flag_present)
         message("${CMAKE_ASM_COMPILER} missing flag \"${flag}\"")
       endif (NOT flag_present)
     endif (flag_present)
   endforeach (flag)
   # let caller decide whether a fatal error or not
   if (NOT flag_present)
     set(CMAKE_ASM_SUPPORTS_INTEL_SYNTAX OFF)
   else (NOT flag_present)
     set(CMAKE_ASM_SUPPORTS_INTEL_SYNTAX ON)
   endif (NOT flag_present)
 endif (UNIX AND NOT APPLE)

 ##################################################
 # Assembler build rule for Makefile generators

 if (APPLE)
   # Despite the docs, -o does not work: cpp prints to stdout.
   set(CMAKE_ASM_NASM_COMPILE_OBJECT
     "${CMAKE_CPP} ${CMAKE_CPP_FLAGS} <FLAGS> <DEFINES> -E <SOURCE> > <OBJECT>.s"
     "<CMAKE_COMMAND> -Dfile=<OBJECT>.s -P \"${cpp2asm_newline_script_path}\""
     "<NASM> ${ASM_FLAGS} -o <OBJECT> <OBJECT>.s"
     )
 elseif (UNIX)
   # we used to have ".ifdef FOO" and to not have it turn into ".ifdef 1" we'd say
   # "-DFOO=FOO", but we now use exclusively preprocessor defines, which is good
   # since our defines are mostly in configure.h where we can't as easily tweak them
   # (update: I do have top-level defines gathered up in ${defines}).
   # so, we don't bother transforming -DFOO into -DFOO=FOO, nor with setting
   # up the --defsym args.
   set(CMAKE_ASM_COMPILE_OBJECT
     "${CMAKE_CPP} ${CMAKE_CPP_FLAGS} <FLAGS> <DEFINES> -E <SOURCE> -o <OBJECT>.s"
     "<CMAKE_COMMAND> -Dfile=<OBJECT>.s -P \"${cpp2asm_newline_script_path}\""
     # not using <FLAGS> b/c of cmake bug #8107 where -Ddynamorio_EXPORTS
     # is passed in: we don't need the include dirs b/c of the cpp step.
     # update: Brad fixed bug #8107: moved -Ddynamorio_EXPORTS from <FLAGS> to <DEFINES>
     # in CMake/Source/cmMakefileTargetGenerator.cxx:1.115 (will be in 2.6.4).
     #
     # we also aren't passing any <DEFINES> since for one thing
     # there's no way to transform to --defsym: luckily we don't need them
     # since using cpp now (see above).
     # FIXME: I tried setting CMAKE_ASM_DEFINE_FLAG to "--defsym " (not clear
     # how to get =1 in there :should verify it's needed) but <DEFINES>
     # comes up empty for me.
     "<CMAKE_ASM_COMPILER> ${ASM_FLAGS} -o <OBJECT> <OBJECT>.s"
     )
 else ()
   # Even if we didn't preprocess we'd need our own rule since cmake doesn't
   # support ml.
   set(CMAKE_ASM_COMPILE_OBJECT
     # There's no way to specify a non-default name with /P: writes to
     # cwd/sourcebase.i.  Could copy with "cmake -E copy" but no way to
     # run get_filename_component on a tag var.  So going with
     # redirection operator which should work in all supported shells.
     #
     # ml can't handle line number markers so using ${CPP_NO_LINENUM}.
     "<CMAKE_C_COMPILER> ${CMAKE_CPP_FLAGS} <FLAGS> <DEFINES> -E ${CPP_NO_LINENUM} <SOURCE> > <OBJECT>.s"
     # cmake does add quotes in custom commands, etc. but not in this rule so we add
     # them to handle paths with spaces:
     "<CMAKE_COMMAND> -Dfile=<OBJECT>.s -P \"${cpp2asm_newline_script_path}\""
     "<CMAKE_ASM_COMPILER> ${ASM_FLAGS} /c /Fo<OBJECT> <OBJECT>.s"
     )
 endif ()

 ##################################################
 # Assembler build commands for Visual Studio generators and
 # for assembly code contained in C source files for all generators

 # Adds rules to pre-process and assemble the assembly file in ${source}.
 # ${extra_defs} should be a list.  It is passed to the pre-processor.
 # ${extra_deps} should be a list.  It is listed as dependencies of the build rule.
 # The name of the generated output will be stored in the output_out variable.
 # This will be an .obj file for VS or an .asm file for Makefiles, but in either case
 # it should be listed as a source of final target executable/library
 # If ${extra_suffix} is non-empty, it will be inserted into the output file
 # and target name before the extension.
 # For VS generators, the caller should add ${tgt_out} to the final target's
 # dependencies.
 function (add_asm_target source output_out tgt_out extra_suffix extra_defs extra_deps)
   if ("${CMAKE_GENERATOR}" MATCHES "Visual Studio")
     get_filename_component(srcbase "${source}" NAME)

     set(s_file "${CMAKE_CURRENT_BINARY_DIR}/${srcbase}${extra_suffix}.s")
     set_source_files_properties("${s_file}" PROPERTIES GENERATED true)
     set(output "${CMAKE_CURRENT_BINARY_DIR}/${srcbase}${extra_suffix}.obj")

     # XXX i#801: a VS2010 bug results in custom commands having all their sources
     # rebuilt which results in racy collision for asm deps (for DR tests, tools_asm).
     # Workaround is to indirect through a dummy .stamp file to avoid
     # chaining sources to custom commands, although this will only
     # include the .obj file in the target link with cmake 2.8.8+.
     # (Alternative is to not list as a source and add to link flags.)
     set(output_stamp "${output}.stamp")
     set_property(SOURCE "${output}" PROPERTY GENERATED true)
     set(output_tgt generate_${srcbase}${extra_suffix})

     add_custom_command(OUTPUT "${output_stamp}"
       DEPENDS
         "${source}"
         "${cpp2asm_newline_script_path}"
         ${extra_deps}
       COMMAND ${CMAKE_COMMAND}
         ARGS -E touch "${output_stamp}"
       COMMAND "${CMAKE_C_COMPILER}" ARGS ${CMAKE_CPP_FLAGS}
         /I "${PROJECT_BINARY_DIR}" ${extra_defs}
         -E ${CPP_NO_LINENUM} "${source}"
         ">" "${s_file}"
       COMMAND "${CMAKE_COMMAND}" ARGS
         -D file=${s_file}
         -P "${cpp2asm_newline_script_path}"
       # We assume we don't need ${defines} => list on cmdline b/c assembly
       # files include configure.h and cpp is where most defines are wanted
       COMMAND "${CMAKE_ASM_COMPILER}" ARGS ${ASM_FLAGS_LIST} /c
         /Fo "${output}"
         "${s_file}"
       WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
       VERBATIM # recommended: p260
       )

     # for correct parallel builds we need a target to avoid
     # duplicate and racy VS per-project rules
     add_custom_target(${output_tgt} DEPENDS "${output_stamp}")
     set(${output_out} "${output}" PARENT_SCOPE)
     set(${tgt_out} ${output_tgt} PARENT_SCOPE)
   else ("${CMAKE_GENERATOR}" MATCHES "Visual Studio")
     if (extra_deps)
       # XXX: how get cmake to analyze #includes of my asm files?
       set_source_files_properties(${source} PROPERTIES OBJECT_DEPENDS
         "${cpp2asm_newline_script_path};${extra_deps}")
     endif (extra_deps)
     # We can't set the extra_defs as source file property b/c caller might
     # use same source for two different targets
     set(${output_out} "${source}" PARENT_SCOPE)
     set(${tgt_out} "" PARENT_SCOPE)
   endif ("${CMAKE_GENERATOR}" MATCHES "Visual Studio")
 endfunction (add_asm_target)

 # Adds rules to pre-process and assemble the assembly portion of the C/C++
 # file ${source}, which must be separated via #ifdef ASM_CODE_ONLY.
 # ${extra_defs} are passed to the pre-processor.
 # ${extra_deps} are listed as dependencies of the build rule.
 # The name of the generated output will be stored in the output_out variable.
 # This will be an .obj file for VS or an .asm file for Makefiles, but in either case
 # it should be listed as a source of final target executable/library
 # If ${extra_suffix} is non-empty, it will be inserted into the output file
 # and target name before the extension.
 # For VS generators, the caller should add ${tgt_out} to the final target's
 # dependencies.
 function (add_split_asm_target source output_out tgt_out
     extra_suffix extra_defs extra_deps)
   get_filename_component(srcbase ${source} NAME)
   set(asm_file "${CMAKE_CURRENT_BINARY_DIR}/${srcbase}${extra_suffix}.asm")

   # Be sure to make extra_defs a list!
   set(extra_defs -DASM_CODE_ONLY ${extra_defs})
   add_asm_target("${asm_file}" asm_output asm_target ""
     "${extra_defs}" "${extra_deps}")

   if ("${CMAKE_GENERATOR}" MATCHES "Visual Studio")
     add_custom_command(TARGET ${asm_target} PRE_BUILD
       COMMAND ${CMAKE_COMMAND}
         ARGS -E copy "${source}" "${asm_file}")
   else ("${CMAKE_GENERATOR}" MATCHES "Visual Studio")
     set_source_files_properties(${asm_file} PROPERTIES
       GENERATED ON COMPILE_FLAGS "-DASM_CODE_ONLY")
     add_custom_command(
       OUTPUT ${asm_file}
       DEPENDS ${source}
       COMMAND ${CMAKE_COMMAND}
       ARGS -E copy "${source}" "${asm_file}"
       VERBATIM # recommended: p260
       )
   endif ("${CMAKE_GENERATOR}" MATCHES "Visual Studio")

   set(${output_out} "${asm_output}" PARENT_SCOPE)
   set(${tgt_out} ${asm_target} PARENT_SCOPE)
 endfunction(add_split_asm_target)
	# **********************************************************
	# Copyright (c) 2010-2014 Google, Inc. All rights reserved.
	# Copyright (c) 2009-2010 VMware, Inc. All rights reserved.
	# **********************************************************

	# Redistribution and use in source and binary forms, with or without
	# modification, are permitted provided that the following conditions are met:
	#
	# * Redistributions of source code must retain the above copyright notice,
	# this list of conditions and the following disclaimer.
	#
	# * Redistributions in binary form must reproduce the above copyright notice,
	# this list of conditions and the following disclaimer in the documentation
	# and/or other materials provided with the distribution.
	#
	# * Neither the name of VMware, Inc. nor the names of its contributors may be
	# used to endorse or promote products derived from this software without
	# specific prior written permission.
	#
	# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	# ARE DISCLAIMED. IN NO EVENT SHALL VMWARE, INC. OR CONTRIBUTORS BE LIABLE
	# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
	# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
	# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
	# DAMAGE.

	###########################################################################
	# Enhanced assembly support for CMake projects
	#
	# Features:
	# + Cmake support for asm with Makefiles and Visual Studio.
	# + Cross-platform asm using Intel syntax and C pre-processor
	# to feed to assembler.
	# + Asm code in C/C++ files (separated via #ifdef ASM_CODE_ONLY) to avoid
	# needing standalone assembly files with 64-bit cl.
	#
	###################################################
	# Usage:
	#
	# Setup:
	# + Place both this file and cpp2asm_add_newlines.cmake in the same
	# directory (or, point at cpp2asm_add_newlines.cmake with the
	# variable ${cpp2asm_newline_script_path}).
	# + Include this file in your CMakeLists.txt file.
	# + For UNIX, the available assembler may not support Intel syntex.
	# In that case, CMAKE_ASM_SUPPORTS_INTEL_SYNTAX will be set to false.
	# The includer of this file can decide whether that's a fatal error.
	#
	# Example setup:
	# include(cpp2asm_support.cmake)
	# if (UNIX)
	# if (NOT CMAKE_ASM_SUPPORTS_INTEL_SYNTAX)
	# <either FATAL_ERROR or point CMAKE_ASM_COMPILER at a gas binary to use>
	# endif ()
	# endif (UNIX)
	#
	# Assembly file:
	# + Write assembly using Intel syntax and the macros in the
	# cpp2asm_defines.h file included in this directory.
	# + Before #include of cpp2asm_defines.h in your asm file, define
	# one of ASSEMBLE_WITH_{GAS,MASM,NASM}
	# + cpp2asm_defines.h is not automatically added as a dependence.
	# If you are using it, pass in its path as part of the extra_deps option.
	# + cpp2asm_defines.h's dir is not automatically added as an include dir.
	# If you are using it, pass in "-I;<path>" as part of the extra_defs option.
	# + The global preprocessor defines are used for Makefile generators.
	# For Visual Studio generators, pass in the defines needed (as a list)
	# as part of the extra_defs option. These extra_defs are NOT honored
	# for Makefile generators and should be added by the caller to the
	# target or global flags.
	# + Have assembly files #include a configure.h or other header to obtain
	# their defines (this file does not support passing them in via cmdline
	# to the preprocessor or the assembler).
	# + For pure assembly files, use add_asm_target(); for split C/C++ + asm files,
	# separate the two pieces via #ifdef ASM_CODE_ONLY and use
	# add_split_asm_target().
	# + For VS generators, add the returned target as a dependence of the final
	# executable/library target to avoid races when building.
	#
	# Example:
	#
	# set(asm_deps "/path/to/cpp2asm_defines.h" "/path/to/configure.h")
	# set(asm_defs -I "/path/to/cpp2asm_defines.h" -I "/path/to/configure.h")
	# add_asm_target(foo.asm foo_asm_src foo_asm_tgt "" "${asm_defs}" ${asm_deps})
	# add_library(bar bar.c ${foo_asm_src})
	# if ("${CMAKE_GENERATOR}" MATCHES "Visual Studio")
	# add_dependencies(bar ${foo_asm_tgt})
	# endif ("${CMAKE_GENERATOR}" MATCHES "Visual Studio")
	#
	###########################################################################

	if ("${CMAKE_GENERATOR}" MATCHES "Visual Studio 10")
	# For i#801 workaround
	cmake_minimum_required(VERSION 2.8.8)
	else ()
	if (APPLE)
	# We want ASM NASM support
	cmake_minimum_required(VERSION 2.8.3)
	else (APPLE)
	# Require 2.6.4 to avoid cmake bug #8639, unless this var is
	# properly set (which it is for DR b/c it has a workaround):
	if (NOT "${CMAKE_ASM_SOURCE_FILE_EXTENSIONS}" MATCHES "asm")
	cmake_minimum_required(VERSION 2.6.4)
	endif ()
	endif (APPLE)
	endif ()

	##################################################
	# Helper files

	if (NOT cpp2asm_newline_script_path)
	# By default we expect cpp2asm_add_newlines.cmake in same dir as this file.
	get_filename_component(my_dir "${CMAKE_CURRENT_LIST_FILE}" PATH)
	set(cpp2asm_newline_script_path "${my_dir}/cpp2asm_add_newlines.cmake")
	endif ()
	if (NOT EXISTS "${cpp2asm_newline_script_path}")
	message(FATAL_ERROR "Cannot find \"${cpp2asm_newline_script_path}\". "
	"Please set the cpp2asm_newline_script_path variable.")
	endif ()

	##################################################
	# Preprocessor location and flags

	if (UNIX)
	# "gcc -E" on a non-.c-extension file gives message:
	# "linker input file unused because linking not done"
	# and doesn't produce any output, so we must use cpp for our .asm files.
	# we assume it's in the same dir.
	get_filename_component(compiler_path ${CMAKE_C_COMPILER} PATH)
	find_program(CMAKE_CPP cpp HINTS "${compiler_path}" DOC "path to C preprocessor")
	if (NOT CMAKE_CPP)
	message(FATAL_ERROR "cpp is required to build")
	endif (NOT CMAKE_CPP)
	mark_as_advanced(CMAKE_CPP)

	set(CPP_KEEP_COMMENTS -C)
	set(CPP_NO_LINENUM -P)
	set(CPP_KEEP_WHITESPACE -traditional-cpp)
	set(CMAKE_CPP_FLAGS "")
	else (UNIX)
	set(CMAKE_CPP ${CMAKE_C_COMPILER})

	set(CPP_KEEP_COMMENTS /C)
	set(CPP_NO_LINENUM /EP)
	set(CPP_KEEP_WHITESPACE "")
	set(CMAKE_CPP_FLAGS "/nologo")
	endif (UNIX)

	##################################################
	# Assembler location and flags

	if (NOT "${CMAKE_GENERATOR}" MATCHES "Visual Studio")
	if (UNIX)
	# i#646: cmake 2.8.5 requires ASM-ATT to find as: but we don't want to change
	# all our vars to have -ATT suffix so we set the search list instead.
	# This must be done prior to enable_language(ASM).
	set(CMAKE_ASM_COMPILER_INIT gas as)
	endif (UNIX)
	# CMake does not support assembly with VS generators
	# (http://public.kitware.com/Bug/view.php?id=11536)
	# so we have to add our own custom commands and targets
	if (APPLE)
	# NASM support was added in 2.8.3. It clears ASM_DIALECT for us.
	enable_language(ASM_NASM)
	else (APPLE)
	enable_language(ASM)
	endif (APPLE)
	endif ()

	if (APPLE)
	# XXX: we may be able to avoid some of this given CMake 2.8.3's NASM support.
	find_program(NASM nasm DOC "path to nasm assembler")
	if (NOT NASM)
	message(FATAL_ERROR "nasm assembler not found: required to build")
	endif (NOT NASM)
	message(STATUS "Found nasm: ${NASM}")
	execute_process(COMMAND ${NASM} -hf OUTPUT_VARIABLE nasm_result ERROR_QUIET)
	if (X64)
	# x64 support added between 0.98.40 and 2.10.07
	if (NOT nasm_result MATCHES macho64)
	message(FATAL_ERROR "nasm is too old: no 64-bit support")
	endif ()
	set(ASM_FLAGS "${ASM_FLAGS} -fmacho64")
	else (X64)
	if (nasm_result MATCHES macho32)
	set(ASM_FLAGS "${ASM_FLAGS} -fmacho32")
	else ()
	set(ASM_FLAGS "${ASM_FLAGS} -fmacho")
	endif ()
	endif (X64)
	if (DEBUG)
	set(ASM_FLAGS "${ASM_FLAGS} -g")
	endif (DEBUG)
	elseif (UNIX)
	if (X86)
	set(ASM_FLAGS "-mmnemonic=intel -msyntax=intel -mnaked-reg")
	if (X64)
	set(ASM_FLAGS "${ASM_FLAGS} --64")
	else (X64)
	# putting --32 last so we fail on -mmnemonic=intel on older as, not --32
	set(ASM_FLAGS "${ASM_FLAGS} --32")
	endif (X64)
	elseif (ARM)
	# No 64-bit support yet so currently no flags.
	endif ()
	set(ASM_FLAGS "${ASM_FLAGS} --noexecstack")
	if (DEBUG)
	set(ASM_FLAGS "${ASM_FLAGS} -g")
	endif (DEBUG)
	else ()
	if (X64)
	find_program(CMAKE_ASM_COMPILER ml64.exe HINTS "${cl_path}" DOC "path to assembler")
	else (X64)
	find_program(CMAKE_ASM_COMPILER ml.exe HINTS "${cl_path}" DOC "path to assembler")
	endif (X64)
	if (NOT CMAKE_ASM_COMPILER)
	message(FATAL_ERROR "assembler not found: required to build")
	endif (NOT CMAKE_ASM_COMPILER)
	message(STATUS "Found assembler: ${CMAKE_ASM_COMPILER}")
	if (NOT DEFINED GENERATE_PDBS OR GENERATE_PDBS)
	set(ASM_DBG "/Zi /Zd")
	else ()
	set(ASM_DBG "")
	endif ()
	set(ASM_FLAGS "/nologo ${ASM_DBG}")
	endif ()
	string(REPLACE " " ";" ASM_FLAGS_LIST "${ASM_FLAGS}")

	if (APPLE)
	# XXX: xcode assembler uses Intel mnemonics but opposite src,dst order!
	# We rely on having nasm installed as a workaround.
	set(CMAKE_ASM_SUPPORTS_INTEL_SYNTAX ON)
	endif (APPLE)
	if (UNIX AND NOT APPLE)
	# We require gas >= 2.18.50 for --32, --64, and the new -msyntax=intel, etc.
	execute_process(COMMAND
	${CMAKE_ASM_COMPILER} --help
	RESULT_VARIABLE asm_result
	ERROR_VARIABLE asm_error
	OUTPUT_VARIABLE asm_out)
	if (asm_result OR asm_error)
	message(FATAL_ERROR "* ${CMAKE_ASM_COMPILER} failed: *\n${asm_error}")
	endif (asm_result OR asm_error)
	# turn the flags into a vector
	string(REGEX REPLACE " " ";" flags_needed "${ASM_FLAGS}")
	# we want "-mmnemonic=intel" to match "-mmnemonic=[att\|intel]"
	string(REGEX REPLACE "=" ".*" flags_needed "${flags_needed}")
	set(flag_present 1)
	foreach (flag ${flags_needed})
	if (flag_present)
	string(REGEX MATCH "${flag}" flag_present "${asm_out}")
	if (NOT flag_present)
	message("${CMAKE_ASM_COMPILER} missing flag \"${flag}\"")
	endif (NOT flag_present)
	endif (flag_present)
	endforeach (flag)
	# let caller decide whether a fatal error or not
	if (NOT flag_present)
	set(CMAKE_ASM_SUPPORTS_INTEL_SYNTAX OFF)
	else (NOT flag_present)
	set(CMAKE_ASM_SUPPORTS_INTEL_SYNTAX ON)
	endif (NOT flag_present)
	endif (UNIX AND NOT APPLE)

	##################################################
	# Assembler build rule for Makefile generators

	if (APPLE)
	# Despite the docs, -o does not work: cpp prints to stdout.
	set(CMAKE_ASM_NASM_COMPILE_OBJECT
	"${CMAKE_CPP} ${CMAKE_CPP_FLAGS} <FLAGS> <DEFINES> -E <SOURCE> > <OBJECT>.s"
	"<CMAKE_COMMAND> -Dfile=<OBJECT>.s -P \"${cpp2asm_newline_script_path}\""
	"<NASM> ${ASM_FLAGS} -o <OBJECT> <OBJECT>.s"
	)
	elseif (UNIX)
	# we used to have ".ifdef FOO" and to not have it turn into ".ifdef 1" we'd say
	# "-DFOO=FOO", but we now use exclusively preprocessor defines, which is good
	# since our defines are mostly in configure.h where we can't as easily tweak them
	# (update: I do have top-level defines gathered up in ${defines}).
	# so, we don't bother transforming -DFOO into -DFOO=FOO, nor with setting
	# up the --defsym args.
	set(CMAKE_ASM_COMPILE_OBJECT
	"${CMAKE_CPP} ${CMAKE_CPP_FLAGS} <FLAGS> <DEFINES> -E <SOURCE> -o <OBJECT>.s"
	"<CMAKE_COMMAND> -Dfile=<OBJECT>.s -P \"${cpp2asm_newline_script_path}\""
	# not using <FLAGS> b/c of cmake bug #8107 where -Ddynamorio_EXPORTS
	# is passed in: we don't need the include dirs b/c of the cpp step.
	# update: Brad fixed bug #8107: moved -Ddynamorio_EXPORTS from <FLAGS> to <DEFINES>
	# in CMake/Source/cmMakefileTargetGenerator.cxx:1.115 (will be in 2.6.4).
	#
	# we also aren't passing any <DEFINES> since for one thing
	# there's no way to transform to --defsym: luckily we don't need them
	# since using cpp now (see above).
	# FIXME: I tried setting CMAKE_ASM_DEFINE_FLAG to "--defsym " (not clear
	# how to get =1 in there :should verify it's needed) but <DEFINES>
	# comes up empty for me.
	"<CMAKE_ASM_COMPILER> ${ASM_FLAGS} -o <OBJECT> <OBJECT>.s"
	)
	else ()
	# Even if we didn't preprocess we'd need our own rule since cmake doesn't
	# support ml.
	set(CMAKE_ASM_COMPILE_OBJECT
	# There's no way to specify a non-default name with /P: writes to
	# cwd/sourcebase.i. Could copy with "cmake -E copy" but no way to
	# run get_filename_component on a tag var. So going with
	# redirection operator which should work in all supported shells.
	#
	# ml can't handle line number markers so using ${CPP_NO_LINENUM}.
	"<CMAKE_C_COMPILER> ${CMAKE_CPP_FLAGS} <FLAGS> <DEFINES> -E ${CPP_NO_LINENUM} <SOURCE> > <OBJECT>.s"
	# cmake does add quotes in custom commands, etc. but not in this rule so we add
	# them to handle paths with spaces:
	"<CMAKE_COMMAND> -Dfile=<OBJECT>.s -P \"${cpp2asm_newline_script_path}\""
	"<CMAKE_ASM_COMPILER> ${ASM_FLAGS} /c /Fo<OBJECT> <OBJECT>.s"
	)
	endif ()

	##################################################
	# Assembler build commands for Visual Studio generators and
	# for assembly code contained in C source files for all generators

	# Adds rules to pre-process and assemble the assembly file in ${source}.
	# ${extra_defs} should be a list. It is passed to the pre-processor.
	# ${extra_deps} should be a list. It is listed as dependencies of the build rule.
	# The name of the generated output will be stored in the output_out variable.
	# This will be an .obj file for VS or an .asm file for Makefiles, but in either case
	# it should be listed as a source of final target executable/library
	# If ${extra_suffix} is non-empty, it will be inserted into the output file
	# and target name before the extension.
	# For VS generators, the caller should add ${tgt_out} to the final target's
	# dependencies.
	function (add_asm_target source output_out tgt_out extra_suffix extra_defs extra_deps)
	if ("${CMAKE_GENERATOR}" MATCHES "Visual Studio")
	get_filename_component(srcbase "${source}" NAME)

	set(s_file "${CMAKE_CURRENT_BINARY_DIR}/${srcbase}${extra_suffix}.s")
	set_source_files_properties("${s_file}" PROPERTIES GENERATED true)
	set(output "${CMAKE_CURRENT_BINARY_DIR}/${srcbase}${extra_suffix}.obj")

	# XXX i#801: a VS2010 bug results in custom commands having all their sources
	# rebuilt which results in racy collision for asm deps (for DR tests, tools_asm).
	# Workaround is to indirect through a dummy .stamp file to avoid
	# chaining sources to custom commands, although this will only
	# include the .obj file in the target link with cmake 2.8.8+.
	# (Alternative is to not list as a source and add to link flags.)
	set(output_stamp "${output}.stamp")
	set_property(SOURCE "${output}" PROPERTY GENERATED true)
	set(output_tgt generate_${srcbase}${extra_suffix})

	add_custom_command(OUTPUT "${output_stamp}"
	DEPENDS
	"${source}"
	"${cpp2asm_newline_script_path}"
	${extra_deps}
	COMMAND ${CMAKE_COMMAND}
	ARGS -E touch "${output_stamp}"
	COMMAND "${CMAKE_C_COMPILER}" ARGS ${CMAKE_CPP_FLAGS}
	/I "${PROJECT_BINARY_DIR}" ${extra_defs}
	-E ${CPP_NO_LINENUM} "${source}"
	">" "${s_file}"
	COMMAND "${CMAKE_COMMAND}" ARGS
	-D file=${s_file}
	-P "${cpp2asm_newline_script_path}"
	# We assume we don't need ${defines} => list on cmdline b/c assembly
	# files include configure.h and cpp is where most defines are wanted
	COMMAND "${CMAKE_ASM_COMPILER}" ARGS ${ASM_FLAGS_LIST} /c
	/Fo "${output}"
	"${s_file}"
	WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
	VERBATIM # recommended: p260
	)

	# for correct parallel builds we need a target to avoid
	# duplicate and racy VS per-project rules
	add_custom_target(${output_tgt} DEPENDS "${output_stamp}")
	set(${output_out} "${output}" PARENT_SCOPE)
	set(${tgt_out} ${output_tgt} PARENT_SCOPE)
	else ("${CMAKE_GENERATOR}" MATCHES "Visual Studio")
	if (extra_deps)
	# XXX: how get cmake to analyze #includes of my asm files?
	set_source_files_properties(${source} PROPERTIES OBJECT_DEPENDS
	"${cpp2asm_newline_script_path};${extra_deps}")
	endif (extra_deps)
	# We can't set the extra_defs as source file property b/c caller might
	# use same source for two different targets
	set(${output_out} "${source}" PARENT_SCOPE)
	set(${tgt_out} "" PARENT_SCOPE)
	endif ("${CMAKE_GENERATOR}" MATCHES "Visual Studio")
	endfunction (add_asm_target)

	# Adds rules to pre-process and assemble the assembly portion of the C/C++
	# file ${source}, which must be separated via #ifdef ASM_CODE_ONLY.
	# ${extra_defs} are passed to the pre-processor.
	# ${extra_deps} are listed as dependencies of the build rule.
	# The name of the generated output will be stored in the output_out variable.
	# This will be an .obj file for VS or an .asm file for Makefiles, but in either case
	# it should be listed as a source of final target executable/library
	# If ${extra_suffix} is non-empty, it will be inserted into the output file
	# and target name before the extension.
	# For VS generators, the caller should add ${tgt_out} to the final target's
	# dependencies.
	function (add_split_asm_target source output_out tgt_out
	extra_suffix extra_defs extra_deps)
	get_filename_component(srcbase ${source} NAME)
	set(asm_file "${CMAKE_CURRENT_BINARY_DIR}/${srcbase}${extra_suffix}.asm")

	# Be sure to make extra_defs a list!
	set(extra_defs -DASM_CODE_ONLY ${extra_defs})
	add_asm_target("${asm_file}" asm_output asm_target ""
	"${extra_defs}" "${extra_deps}")

	if ("${CMAKE_GENERATOR}" MATCHES "Visual Studio")
	add_custom_command(TARGET ${asm_target} PRE_BUILD
	COMMAND ${CMAKE_COMMAND}
	ARGS -E copy "${source}" "${asm_file}")
	else ("${CMAKE_GENERATOR}" MATCHES "Visual Studio")
	set_source_files_properties(${asm_file} PROPERTIES
	GENERATED ON COMPILE_FLAGS "-DASM_CODE_ONLY")
	add_custom_command(
	OUTPUT ${asm_file}
	DEPENDS ${source}
	COMMAND ${CMAKE_COMMAND}
	ARGS -E copy "${source}" "${asm_file}"
	VERBATIM # recommended: p260
	)
	endif ("${CMAKE_GENERATOR}" MATCHES "Visual Studio")

	set(${output_out} "${asm_output}" PARENT_SCOPE)
	set(${tgt_out} ${asm_target} PARENT_SCOPE)
	endfunction(add_split_asm_target)