SConstruct

   1 # -*- mode:python -*-
   2
   3 # Copyright (c) 2013, 2015-2020 ARM Limited
   4 # All rights reserved.
   5 #
   6 # The license below extends only to copyright in the software and shall
   7 # not be construed as granting a license to any other intellectual
   8 # property including but not limited to intellectual property relating
   9 # to a hardware implementation of the functionality of the software
  10 # licensed hereunder.  You may use the software subject to the license
  11 # terms below provided that you ensure that this notice is replicated
  12 # unmodified and in its entirety in all distributions of the software,
  13 # modified or unmodified, in source code or in binary form.
  14 #
  15 # Copyright (c) 2011 Advanced Micro Devices, Inc.
  16 # Copyright (c) 2009 The Hewlett-Packard Development Company
  17 # Copyright (c) 2004-2005 The Regents of The University of Michigan
  18 # All rights reserved.
  19 #
  20 # Redistribution and use in source and binary forms, with or without
  21 # modification, are permitted provided that the following conditions are
  22 # met: redistributions of source code must retain the above copyright
  23 # notice, this list of conditions and the following disclaimer;
  24 # redistributions in binary form must reproduce the above copyright
  25 # notice, this list of conditions and the following disclaimer in the
  26 # documentation and/or other materials provided with the distribution;
  27 # neither the name of the copyright holders nor the names of its
  28 # contributors may be used to endorse or promote products derived from
  29 # this software without specific prior written permission.
  30 #
  31 # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32 # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33 # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  34 # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35 # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  36 # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  37 # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  38 # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  39 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  40 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  41 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  42
  43 ###################################################
  44 #
  45 # SCons top-level build description (SConstruct) file.
  46 #
  47 # While in this directory ('gem5'), just type 'scons' to build the default
  48 # configuration (see below), or type 'scons build/<CONFIG>/<binary>'
  49 # to build some other configuration (e.g., 'build/X86/gem5.opt' for
  50 # the optimized full-system version).
  51 #
  52 # You can build gem5 in a different directory as long as there is a
  53 # 'build/<CONFIG>' somewhere along the target path.  The build system
  54 # expects that all configs under the same build directory are being
  55 # built for the same host system.
  56 #
  57 # Examples:
  58 #
  59 #   The following two commands are equivalent.  The '-u' option tells
  60 #   scons to search up the directory tree for this SConstruct file.
  61 #   % cd <path-to-src>/gem5 ; scons build/X86/gem5.debug
  62 #   % cd <path-to-src>/gem5/build/X86; scons -u gem5.debug
  63 #
  64 #   The following two commands are equivalent and demonstrate building
  65 #   in a directory outside of the source tree.  The '-C' option tells
  66 #   scons to chdir to the specified directory to find this SConstruct
  67 #   file.
  68 #   % cd <path-to-src>/gem5 ; scons /local/foo/build/X86/gem5.debug
  69 #   % cd /local/foo/build/X86; scons -C <path-to-src>/gem5 gem5.debug
  70 #
  71 # You can use 'scons -H' to print scons options.  If you're in this
  72 # 'gem5' directory (or use -u or -C to tell scons where to find this
  73 # file), you can use 'scons -h' to print all the gem5-specific build
  74 # options as well.
  75 #
  76 ###################################################
  77
  78 # Global Python includes
  79 import atexit
  80 import itertools
  81 import os
  82 import re
  83 import shutil
  84 import subprocess
  85 import sys
  86
  87 from os import mkdir, environ
  88 from os.path import abspath, basename, dirname, expanduser, normpath
  89 from os.path import exists,  isdir, isfile
  90 from os.path import join as joinpath, split as splitpath
  91 from re import match
  92
  93 # SCons includes
  94 import SCons
  95 import SCons.Node
  96 import SCons.Node.FS
  97
  98 from m5.util import compareVersions, readCommand, readCommandWithReturn
  99
 100 AddOption('--colors', dest='use_colors', action='store_true',
 101           help="Add color to abbreviated scons output")
 102 AddOption('--no-colors', dest='use_colors', action='store_false',
 103           help="Don't add color to abbreviated scons output")
 104 AddOption('--with-cxx-config', action='store_true',
 105           help="Build with support for C++-based configuration")
 106 AddOption('--default',
 107           help='Override which build_opts file to use for defaults')
 108 AddOption('--ignore-style', action='store_true',
 109           help='Disable style checking hooks')
 110 AddOption('--gold-linker', action='store_true', help='Use the gold linker')
 111 AddOption('--no-compress-debug', action='store_true',
 112           help="Don't compress debug info in build files")
 113 AddOption('--no-lto', action='store_true',
 114           help='Disable Link-Time Optimization for fast')
 115 AddOption('--verbose', action='store_true',
 116           help='Print full tool command lines')
 117 AddOption('--without-python', action='store_true',
 118           help='Build without Python configuration support')
 119 AddOption('--without-tcmalloc', action='store_true',
 120           help='Disable linking against tcmalloc')
 121 AddOption('--with-ubsan', action='store_true',
 122           help='Build with Undefined Behavior Sanitizer if available')
 123 AddOption('--with-asan', action='store_true',
 124           help='Build with Address Sanitizer if available')
 125 AddOption('--with-systemc-tests', action='store_true',
 126           help='Build systemc tests')
 127
 128 from gem5_scons import Transform, error, warning, summarize_warnings
 129 import gem5_scons
 130
 131 ########################################################################
 132 #
 133 # Set up the main build environment.
 134 #
 135 ########################################################################
 136
 137 main = Environment(tools=['default', 'git'])
 138
 139 from gem5_scons.util import get_termcap
 140 termcap = get_termcap()
 141
 142 main_dict_keys = main.Dictionary().keys()
 143
 144 # Check that we have a C/C++ compiler
 145 if not ('CC' in main_dict_keys and 'CXX' in main_dict_keys):
 146     error("No C++ compiler installed (package g++ on Ubuntu and RedHat)")
 147
 148 ###################################################
 149 #
 150 # Figure out which configurations to set up based on the path(s) of
 151 # the target(s).
 152 #
 153 ###################################################
 154
 155 # Find default configuration & binary.
 156 Default(environ.get('M5_DEFAULT_BINARY', 'build/ARM/gem5.debug'))
 157
 158 # helper function: find last occurrence of element in list
 159 def rfind(l, elt, offs = -1):
 160     for i in range(len(l)+offs, 0, -1):
 161         if l[i] == elt:
 162             return i
 163     raise ValueError("element not found")
 164
 165 # Take a list of paths (or SCons Nodes) and return a list with all
 166 # paths made absolute and ~-expanded.  Paths will be interpreted
 167 # relative to the launch directory unless a different root is provided
 168 def makePathListAbsolute(path_list, root=GetLaunchDir()):
 169     return [abspath(joinpath(root, expanduser(str(p))))
 170             for p in path_list]
 171
 172 # Each target must have 'build' in the interior of the path; the
 173 # directory below this will determine the build parameters.  For
 174 # example, for target 'foo/bar/build/X86/arch/x86/blah.do' we
 175 # recognize that X86 specifies the configuration because it
 176 # follow 'build' in the build path.
 177
 178 # The funky assignment to "[:]" is needed to replace the list contents
 179 # in place rather than reassign the symbol to a new list, which
 180 # doesn't work (obviously!).
 181 BUILD_TARGETS[:] = makePathListAbsolute(BUILD_TARGETS)
 182
 183 # Generate a list of the unique build roots and configs that the
 184 # collected targets reference.
 185 variant_paths = []
 186 build_root = None
 187 for t in BUILD_TARGETS:
 188     path_dirs = t.split('/')
 189     try:
 190         build_top = rfind(path_dirs, 'build', -2)
 191     except:
 192         error("No non-leaf 'build' dir found on target path.", t)
 193     this_build_root = joinpath('/',*path_dirs[:build_top+1])
 194     if not build_root:
 195         build_root = this_build_root
 196     else:
 197         if this_build_root != build_root:
 198             error("build targets not under same build root\n"
 199                   "  %s\n  %s" % (build_root, this_build_root))
 200     variant_path = joinpath('/',*path_dirs[:build_top+2])
 201     if variant_path not in variant_paths:
 202         variant_paths.append(variant_path)
 203
 204 # Make sure build_root exists (might not if this is the first build there)
 205 if not isdir(build_root):
 206     mkdir(build_root)
 207 main['BUILDROOT'] = build_root
 208
 209 Export('main')
 210
 211 main.SConsignFile(joinpath(build_root, "sconsign"))
 212
 213 # Default duplicate option is to use hard links, but this messes up
 214 # when you use emacs to edit a file in the target dir, as emacs moves
 215 # file to file~ then copies to file, breaking the link.  Symbolic
 216 # (soft) links work better.
 217 main.SetOption('duplicate', 'soft-copy')
 218
 219 #
 220 # Set up global sticky variables... these are common to an entire build
 221 # tree (not specific to a particular build like X86)
 222 #
 223
 224 global_vars_file = joinpath(build_root, 'variables.global')
 225
 226 global_vars = Variables(global_vars_file, args=ARGUMENTS)
 227
 228 global_vars.AddVariables(
 229     ('CC', 'C compiler', environ.get('CC', main['CC'])),
 230     ('CXX', 'C++ compiler', environ.get('CXX', main['CXX'])),
 231     ('CCFLAGS_EXTRA', 'Extra C and C++ compiler flags', ''),
 232     ('LDFLAGS_EXTRA', 'Extra linker flags', ''),
 233     ('MARSHAL_CCFLAGS_EXTRA', 'Extra C and C++ marshal compiler flags', ''),
 234     ('MARSHAL_LDFLAGS_EXTRA', 'Extra marshal linker flags', ''),
 235     ('PYTHON_CONFIG', 'Python config binary to use',
 236      [ 'python3-config', 'python-config']
 237     ),
 238     ('PROTOC', 'protoc tool', environ.get('PROTOC', 'protoc')),
 239     ('BATCH', 'Use batch pool for build and tests', False),
 240     ('BATCH_CMD', 'Batch pool submission command name', 'qdo'),
 241     ('M5_BUILD_CACHE', 'Cache built objects in this directory', False),
 242     ('EXTRAS', 'Add extra directories to the compilation', '')
 243     )
 244
 245 # Update main environment with values from ARGUMENTS & global_vars_file
 246 global_vars.Update(main)
 247 Help('''
 248 Global build variables:
 249 {help}
 250 '''.format(help=global_vars.GenerateHelpText(main)), append=True)
 251
 252 # Save sticky variable settings back to current variables file
 253 global_vars.Save(global_vars_file, main)
 254
 255 # Parse EXTRAS variable to build list of all directories where we're
 256 # look for sources etc.  This list is exported as extras_dir_list.
 257 base_dir = Dir('#src').abspath
 258 if main['EXTRAS']:
 259     extras_dir_list = makePathListAbsolute(main['EXTRAS'].split(':'))
 260 else:
 261     extras_dir_list = []
 262
 263 Export('base_dir')
 264 Export('extras_dir_list')
 265
 266 # the ext directory should be on the #includes path
 267 main.Append(CPPPATH=[Dir('ext')])
 268
 269 # Add shared top-level headers
 270 main.Prepend(CPPPATH=Dir('include'))
 271
 272 if GetOption('verbose'):
 273     def MakeAction(action, string, *args, **kwargs):
 274         return Action(action, *args, **kwargs)
 275 else:
 276     MakeAction = Action
 277     main['CCCOMSTR']        = Transform("CC")
 278     main['CXXCOMSTR']       = Transform("CXX")
 279     main['ASCOMSTR']        = Transform("AS")
 280     main['ARCOMSTR']        = Transform("AR", 0)
 281     main['LINKCOMSTR']      = Transform("LINK", 0)
 282     main['SHLINKCOMSTR']    = Transform("SHLINK", 0)
 283     main['RANLIBCOMSTR']    = Transform("RANLIB", 0)
 284     main['M4COMSTR']        = Transform("M4")
 285     main['SHCCCOMSTR']      = Transform("SHCC")
 286     main['SHCXXCOMSTR']     = Transform("SHCXX")
 287 Export('MakeAction')
 288
 289 # Initialize the Link-Time Optimization (LTO) flags
 290 main['LTO_CCFLAGS'] = []
 291 main['LTO_LDFLAGS'] = []
 292
 293 # According to the readme, tcmalloc works best if the compiler doesn't
 294 # assume that we're using the builtin malloc and friends. These flags
 295 # are compiler-specific, so we need to set them after we detect which
 296 # compiler we're using.
 297 main['TCMALLOC_CCFLAGS'] = []
 298
 299 # Platform-specific configuration.  Note again that we assume that all
 300 # builds under a given build root run on the same host platform.
 301 conf = gem5_scons.Configure(main)
 302
 303 CXX_version = readCommand([main['CXX'],'--version'], exception=False)
 304 CXX_V = readCommand([main['CXX'],'-V'], exception=False)
 305
 306 main['GCC'] = CXX_version and CXX_version.find('g++') >= 0
 307 main['CLANG'] = CXX_version and CXX_version.find('clang') >= 0
 308 if main['GCC'] + main['CLANG'] > 1:
 309     error('Two compilers enabled at once?')
 310
 311 # Set up default C++ compiler flags
 312 if main['GCC'] or main['CLANG']:
 313     # As gcc and clang share many flags, do the common parts here
 314     main.Append(CCFLAGS=['-pipe'])
 315     main.Append(CCFLAGS=['-fno-strict-aliasing'])
 316     # Enable -Wall and -Wextra and then disable the few warnings that
 317     # we consistently violate
 318     main.Append(CCFLAGS=['-Wall', '-Wundef', '-Wextra',
 319                          '-Wno-sign-compare', '-Wno-unused-parameter'])
 320     # We always compile using C++14
 321     main.Append(CXXFLAGS=['-std=c++14'])
 322     if sys.platform.startswith('freebsd'):
 323         main.Append(CCFLAGS=['-I/usr/local/include'])
 324         main.Append(CXXFLAGS=['-I/usr/local/include'])
 325
 326     conf.CheckLinkFlag('-Wl,--as-needed')
 327     if GetOption('gold_linker'):
 328         main.Append(LINKFLAGS='-fuse-ld=gold')
 329
 330     # Treat warnings as errors but white list some warnings that we
 331     # want to allow (e.g., deprecation warnings).
 332     main.Append(CCFLAGS=['-Werror',
 333                          '-Wno-error=deprecated-declarations',
 334                          '-Wno-error=deprecated',
 335                         ])
 336 else:
 337     error('\n'.join((
 338           "Don't know what compiler options to use for your compiler.",
 339           "compiler: " + main['CXX'],
 340           "version: " + CXX_version.replace('\n', '<nl>') if
 341                 CXX_version else 'COMMAND NOT FOUND!',
 342           "If you're trying to use a compiler other than GCC",
 343           "or clang, there appears to be something wrong with your",
 344           "environment.",
 345           "",
 346           "If you are trying to use a compiler other than those listed",
 347           "above you will need to ease fix SConstruct and ",
 348           "src/SConscript to support that compiler.")))
 349
 350 if main['GCC']:
 351     gcc_version = readCommand([main['CXX'], '-dumpversion'], exception=False)
 352     if compareVersions(gcc_version, "5") < 0:
 353         error('gcc version 5 or newer required.\n'
 354               'Installed version:', gcc_version)
 355         Exit(1)
 356
 357     main['GCC_VERSION'] = gcc_version
 358
 359     # Add the appropriate Link-Time Optimization (LTO) flags
 360     # unless LTO is explicitly turned off. Note that these flags
 361     # are only used by the fast target.
 362     if not GetOption('no_lto'):
 363         # Pass the LTO flag when compiling to produce GIMPLE
 364         # output, we merely create the flags here and only append
 365         # them later
 366         main['LTO_CCFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
 367
 368         # Use the same amount of jobs for LTO as we are running
 369         # scons with
 370         main['LTO_LDFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
 371
 372     main.Append(TCMALLOC_CCFLAGS=['-fno-builtin-malloc', '-fno-builtin-calloc',
 373                                   '-fno-builtin-realloc', '-fno-builtin-free'])
 374
 375 elif main['CLANG']:
 376     clang_version_re = re.compile(".* version (\d+\.\d+)")
 377     clang_version_match = clang_version_re.search(CXX_version)
 378     if (clang_version_match):
 379         clang_version = clang_version_match.groups()[0]
 380         if compareVersions(clang_version, "3.9") < 0:
 381             error('clang version 3.9 or newer required.\n'
 382                   'Installed version:', clang_version)
 383     else:
 384         error('Unable to determine clang version.')
 385
 386     # clang has a few additional warnings that we disable, extraneous
 387     # parantheses are allowed due to Ruby's printing of the AST,
 388     # finally self assignments are allowed as the generated CPU code
 389     # is relying on this
 390     main.Append(CCFLAGS=['-Wno-parentheses',
 391                          '-Wno-self-assign',
 392                          # Some versions of libstdc++ (4.8?) seem to
 393                          # use struct hash and class hash
 394                          # interchangeably.
 395                          '-Wno-mismatched-tags',
 396                          ])
 397     conf.CheckCxxFlag('-Wno-c99-designator')
 398     conf.CheckCxxFlag('-Wno-defaulted-function-deleted')
 399
 400     main.Append(TCMALLOC_CCFLAGS=['-fno-builtin'])
 401
 402     # On Mac OS X/Darwin we need to also use libc++ (part of XCode) as
 403     # opposed to libstdc++, as the later is dated.
 404     if sys.platform == "darwin":
 405         main.Append(CXXFLAGS=['-stdlib=libc++'])
 406         main.Append(LIBS=['c++'])
 407
 408     # On FreeBSD we need libthr.
 409     if sys.platform.startswith('freebsd'):
 410         main.Append(LIBS=['thr'])
 411
 412 # Add sanitizers flags
 413 sanitizers=[]
 414 if GetOption('with_ubsan'):
 415     sanitizers.append('undefined')
 416 if GetOption('with_asan'):
 417     # Available for gcc >= 5 or llvm >= 3.1 both a requirement
 418     # by the build system
 419     sanitizers.append('address')
 420     suppressions_file = Dir('util').File('lsan-suppressions').get_abspath()
 421     suppressions_opt = 'suppressions=%s' % suppressions_file
 422     main['ENV']['LSAN_OPTIONS'] = ':'.join([suppressions_opt,
 423                                             'print_suppressions=0'])
 424     print()
 425     warning('To suppress false positive leaks, set the LSAN_OPTIONS '
 426             'environment variable to "%s" when running gem5' %
 427             suppressions_opt)
 428     warning('LSAN_OPTIONS=suppressions=%s' % suppressions_opt)
 429     print()
 430 if sanitizers:
 431     sanitizers = ','.join(sanitizers)
 432     if main['GCC'] or main['CLANG']:
 433         main.Append(CCFLAGS=['-fsanitize=%s' % sanitizers,
 434                              '-fno-omit-frame-pointer'],
 435                     LINKFLAGS='-fsanitize=%s' % sanitizers)
 436     else:
 437         warning("Don't know how to enable %s sanitizer(s) for your "
 438                 "compiler." % sanitizers)
 439
 440 # Set up common yacc/bison flags (needed for Ruby)
 441 main['YACCFLAGS'] = '-d'
 442 main['YACCHXXFILESUFFIX'] = '.hh'
 443
 444 # Do this after we save setting back, or else we'll tack on an
 445 # extra 'qdo' every time we run scons.
 446 if main['BATCH']:
 447     main['CC']     = main['BATCH_CMD'] + ' ' + main['CC']
 448     main['CXX']    = main['BATCH_CMD'] + ' ' + main['CXX']
 449     main['AS']     = main['BATCH_CMD'] + ' ' + main['AS']
 450     main['AR']     = main['BATCH_CMD'] + ' ' + main['AR']
 451     main['RANLIB'] = main['BATCH_CMD'] + ' ' + main['RANLIB']
 452
 453 if sys.platform == 'cygwin':
 454     # cygwin has some header file issues...
 455     main.Append(CCFLAGS=["-Wno-uninitialized"])
 456
 457
 458 have_pkg_config = readCommand(['pkg-config', '--version'], exception='')
 459
 460 # Check for the protobuf compiler
 461 try:
 462     main['HAVE_PROTOC'] = True
 463     protoc_version = readCommand([main['PROTOC'], '--version']).split()
 464
 465     # First two words should be "libprotoc x.y.z"
 466     if len(protoc_version) < 2 or protoc_version[0] != 'libprotoc':
 467         warning('Protocol buffer compiler (protoc) not found.\n'
 468                 'Please install protobuf-compiler for tracing support.')
 469         main['HAVE_PROTOC'] = False
 470     else:
 471         # Based on the availability of the compress stream wrappers,
 472         # require 2.1.0
 473         min_protoc_version = '2.1.0'
 474         if compareVersions(protoc_version[1], min_protoc_version) < 0:
 475             warning('protoc version', min_protoc_version,
 476                     'or newer required.\n'
 477                     'Installed version:', protoc_version[1])
 478             main['HAVE_PROTOC'] = False
 479         else:
 480             # Attempt to determine the appropriate include path and
 481             # library path using pkg-config, that means we also need to
 482             # check for pkg-config. Note that it is possible to use
 483             # protobuf without the involvement of pkg-config. Later on we
 484             # check go a library config check and at that point the test
 485             # will fail if libprotobuf cannot be found.
 486             if have_pkg_config:
 487                 try:
 488                     # Attempt to establish what linking flags to add for
 489                     # protobuf
 490                     # using pkg-config
 491                     main.ParseConfig(
 492                             'pkg-config --cflags --libs-only-L protobuf')
 493                 except:
 494                     warning('pkg-config could not get protobuf flags.')
 495 except Exception as e:
 496     warning('While checking protoc version:', str(e))
 497     main['HAVE_PROTOC'] = False
 498
 499
 500 # Cache build files in the supplied directory.
 501 if main['M5_BUILD_CACHE']:
 502     print('Using build cache located at', main['M5_BUILD_CACHE'])
 503     CacheDir(main['M5_BUILD_CACHE'])
 504
 505 if not GetOption('no_compress_debug'):
 506     if not conf.CheckCxxFlag('-gz'):
 507         warning("Can't enable object file debug section compression")
 508     if not conf.CheckLinkFlag('-gz'):
 509         warning("Can't enable executable debug section compression")
 510
 511 main['USE_PYTHON'] = not GetOption('without_python')
 512 if main['USE_PYTHON']:
 513     # Find Python include and library directories for embedding the
 514     # interpreter. We rely on python-config to resolve the appropriate
 515     # includes and linker flags. ParseConfig does not seem to understand
 516     # the more exotic linker flags such as -Xlinker and -export-dynamic so
 517     # we add them explicitly below. If you want to link in an alternate
 518     # version of python, see above for instructions on how to invoke
 519     # scons with the appropriate PATH set.
 520
 521     python_config = main.Detect(main['PYTHON_CONFIG'])
 522     if python_config is None:
 523         error("Can't find a suitable python-config, tried %s" % \
 524               main['PYTHON_CONFIG'])
 525
 526     print("Info: Using Python config: %s" % (python_config, ))
 527
 528     py_includes = readCommand([python_config, '--includes'],
 529                               exception='').split()
 530     py_includes = list(filter(
 531         lambda s: match(r'.*\/include\/.*',s), py_includes))
 532     # Strip the -I from the include folders before adding them to the
 533     # CPPPATH
 534     py_includes = list(map(
 535         lambda s: s[2:] if s.startswith('-I') else s, py_includes))
 536     main.Append(CPPPATH=py_includes)
 537
 538     # Read the linker flags and split them into libraries and other link
 539     # flags. The libraries are added later through the call the CheckLib.
 540     # Note: starting in Python 3.8 the --embed flag is required to get the
 541     # -lpython3.8 linker flag
 542     retcode, cmd_stdout = readCommandWithReturn(
 543         [python_config, '--ldflags', '--embed'], exception='')
 544     if retcode != 0:
 545         # If --embed isn't detected then we're running python <3.8
 546         retcode, cmd_stdout = readCommandWithReturn(
 547             [python_config, '--ldflags'], exception='')
 548
 549     # Checking retcode again
 550     if retcode != 0:
 551         error("Failing on python-config --ldflags command")
 552
 553     py_ld_flags = cmd_stdout.split()
 554
 555     py_libs = []
 556     for lib in py_ld_flags:
 557          if not lib.startswith('-l'):
 558              main.Append(LINKFLAGS=[lib])
 559          else:
 560              lib = lib[2:]
 561              if lib not in py_libs:
 562                  py_libs.append(lib)
 563
 564     # verify that this stuff works
 565     if not conf.CheckHeader('Python.h', '<>'):
 566         error("Check failed for Python.h header in",
 567                 ' '.join(py_includes), "\n"
 568               "Two possible reasons:\n"
 569               "1. Python headers are not installed (You can install the "
 570               "package python-dev on Ubuntu and RedHat)\n"
 571               "2. SCons is using a wrong C compiler. This can happen if "
 572               "CC has the wrong value.\n"
 573               "CC = %s" % main['CC'])
 574
 575     for lib in py_libs:
 576         if not conf.CheckLib(lib):
 577             error("Can't find library %s required by python." % lib)
 578
 579     main.Prepend(CPPPATH=Dir('ext/pybind11/include/'))
 580
 581     marshal_env = main.Clone()
 582
 583     # Bare minimum environment that only includes python
 584     marshal_env.Append(CCFLAGS='$MARSHAL_CCFLAGS_EXTRA')
 585     marshal_env.Append(LINKFLAGS='$MARSHAL_LDFLAGS_EXTRA')
 586
 587     py_version = conf.CheckPythonLib()
 588     if not py_version:
 589         error("Can't find a working Python installation")
 590
 591     # Found a working Python installation. Check if it meets minimum
 592     # requirements.
 593     if py_version[0] < 3 or \
 594     (py_version[0] == 3 and py_version[1] < 6):
 595         error('Python version too old. Version 3.6 or newer is required.')
 596     elif py_version[0] > 3:
 597         warning('Python version too new. Python 3 expected.')
 598
 599 # On Solaris you need to use libsocket for socket ops
 600 if not conf.CheckLibWithHeader(None, 'sys/socket.h', 'C++', 'accept(0,0,0);'):
 601    if not conf.CheckLibWithHeader('socket', 'sys/socket.h',
 602                                   'C++', 'accept(0,0,0);'):
 603        error("Can't find library with socket calls (e.g. accept()).")
 604
 605 # Check for zlib.  If the check passes, libz will be automatically
 606 # added to the LIBS environment variable.
 607 if not conf.CheckLibWithHeader('z', 'zlib.h', 'C++','zlibVersion();'):
 608     error('Did not find needed zlib compression library '
 609           'and/or zlib.h header file.\n'
 610           'Please install zlib and try again.')
 611
 612 # If we have the protobuf compiler, also make sure we have the
 613 # development libraries. If the check passes, libprotobuf will be
 614 # automatically added to the LIBS environment variable. After
 615 # this, we can use the HAVE_PROTOBUF flag to determine if we have
 616 # got both protoc and libprotobuf available.
 617 main['HAVE_PROTOBUF'] = main['HAVE_PROTOC'] and \
 618     conf.CheckLibWithHeader('protobuf', 'google/protobuf/message.h',
 619                             'C++', 'GOOGLE_PROTOBUF_VERIFY_VERSION;')
 620
 621 # Valgrind gets much less confused if you tell it when you're using
 622 # alternative stacks.
 623 main['HAVE_VALGRIND'] = conf.CheckCHeader('valgrind/valgrind.h')
 624
 625 # If we have the compiler but not the library, print another warning.
 626 if main['HAVE_PROTOC'] and not main['HAVE_PROTOBUF']:
 627     warning('Did not find protocol buffer library and/or headers.\n'
 628             'Please install libprotobuf-dev for tracing support.')
 629
 630 # Check for librt.
 631 have_posix_clock = \
 632     conf.CheckLibWithHeader([None, 'rt'], 'time.h', 'C',
 633                             'clock_nanosleep(0,0,NULL,NULL);')
 634 if not have_posix_clock:
 635     warning("Can't find library for POSIX clocks.")
 636
 637 have_posix_timers = \
 638     conf.CheckLibWithHeader([None, 'rt'], [ 'time.h', 'signal.h' ], 'C',
 639                             'timer_create(CLOCK_MONOTONIC, NULL, NULL);')
 640
 641 if not GetOption('without_tcmalloc'):
 642     if conf.CheckLib('tcmalloc'):
 643         main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
 644     elif conf.CheckLib('tcmalloc_minimal'):
 645         main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
 646     else:
 647         warning("You can get a 12% performance improvement by "
 648                 "installing tcmalloc (libgoogle-perftools-dev package "
 649                 "on Ubuntu or RedHat).")
 650
 651
 652 # Detect back trace implementations. The last implementation in the
 653 # list will be used by default.
 654 backtrace_impls = [ "none" ]
 655
 656 backtrace_checker = 'char temp;' + \
 657     ' backtrace_symbols_fd((void*)&temp, 0, 0);'
 658 if conf.CheckLibWithHeader(None, 'execinfo.h', 'C', backtrace_checker):
 659     backtrace_impls.append("glibc")
 660 elif conf.CheckLibWithHeader('execinfo', 'execinfo.h', 'C',
 661                              backtrace_checker):
 662     # NetBSD and FreeBSD need libexecinfo.
 663     backtrace_impls.append("glibc")
 664     main.Append(LIBS=['execinfo'])
 665
 666 if backtrace_impls[-1] == "none":
 667     default_backtrace_impl = "none"
 668     warning("No suitable back trace implementation found.")
 669
 670 # Check for <fenv.h> (C99 FP environment control)
 671 have_fenv = conf.CheckHeader('fenv.h', '<>')
 672 if not have_fenv:
 673     warning("Header file <fenv.h> not found.\n"
 674             "This host has no IEEE FP rounding mode control.")
 675
 676 # Check for <png.h> (libpng library needed if wanting to dump
 677 # frame buffer image in png format)
 678 have_png = conf.CheckHeader('png.h', '<>')
 679 if not have_png:
 680     warning("Header file <png.h> not found.\n"
 681             "This host has no libpng library.\n"
 682             "Disabling support for PNG framebuffers.")
 683
 684 # Check if we should enable KVM-based hardware virtualization. The API
 685 # we rely on exists since version 2.6.36 of the kernel, but somehow
 686 # the KVM_API_VERSION does not reflect the change. We test for one of
 687 # the types as a fall back.
 688 have_kvm = conf.CheckHeader('linux/kvm.h', '<>')
 689 if not have_kvm:
 690     print("Info: Compatible header file <linux/kvm.h> not found, "
 691           "disabling KVM support.")
 692
 693 # Check if the TUN/TAP driver is available.
 694 have_tuntap = conf.CheckHeader('linux/if_tun.h', '<>')
 695 if not have_tuntap:
 696     print("Info: Compatible header file <linux/if_tun.h> not found.")
 697
 698 # x86 needs support for xsave. We test for the structure here since we
 699 # won't be able to run new tests by the time we know which ISA we're
 700 # targeting.
 701 have_kvm_xsave = conf.CheckTypeSize('struct kvm_xsave',
 702                                     '#include <linux/kvm.h>') != 0
 703
 704 # Check if the requested target ISA is compatible with the host
 705 def is_isa_kvm_compatible(isa):
 706     try:
 707         import platform
 708         host_isa = platform.machine()
 709     except:
 710         warning("Failed to determine host ISA.")
 711         return False
 712
 713     if not have_posix_timers:
 714         warning("Can not enable KVM, host seems to lack support "
 715                 "for POSIX timers")
 716         return False
 717
 718     if isa == "arm":
 719         return host_isa in ( "armv7l", "aarch64" )
 720     elif isa == "x86":
 721         if host_isa != "x86_64":
 722             return False
 723
 724         if not have_kvm_xsave:
 725             warning("KVM on x86 requires xsave support in kernel headers.")
 726             return False
 727
 728         return True
 729     else:
 730         return False
 731
 732
 733 # Check if the exclude_host attribute is available. We want this to
 734 # get accurate instruction counts in KVM.
 735 main['HAVE_PERF_ATTR_EXCLUDE_HOST'] = conf.CheckMember(
 736     'linux/perf_event.h', 'struct perf_event_attr', 'exclude_host')
 737
 738 def check_hdf5():
 739     return \
 740         conf.CheckLibWithHeader('hdf5', 'hdf5.h', 'C',
 741                                 'H5Fcreate("", 0, 0, 0);') and \
 742         conf.CheckLibWithHeader('hdf5_cpp', 'H5Cpp.h', 'C++',
 743                                 'H5::H5File("", 0);')
 744
 745 def check_hdf5_pkg(name):
 746     print("Checking for %s using pkg-config..." % name, end="")
 747     if not have_pkg_config:
 748         print(" pkg-config not found")
 749         return False
 750
 751     try:
 752         main.ParseConfig('pkg-config --cflags-only-I --libs-only-L %s' % name)
 753         print(" yes")
 754         return True
 755     except:
 756         print(" no")
 757         return False
 758
 759 # Check if there is a pkg-config configuration for hdf5. If we find
 760 # it, setup the environment to enable linking and header inclusion. We
 761 # don't actually try to include any headers or link with hdf5 at this
 762 # stage.
 763 if not check_hdf5_pkg('hdf5-serial'):
 764     check_hdf5_pkg('hdf5')
 765
 766 # Check if the HDF5 libraries can be found. This check respects the
 767 # include path and library path provided by pkg-config. We perform
 768 # this check even if there isn't a pkg-config configuration for hdf5
 769 # since some installations don't use pkg-config.
 770 have_hdf5 = check_hdf5()
 771 if not have_hdf5:
 772     print("Warning: Couldn't find any HDF5 C++ libraries. Disabling")
 773     print("         HDF5 support.")
 774
 775 ######################################################################
 776 #
 777 # Finish the configuration
 778 #
 779 main = conf.Finish()
 780
 781 ######################################################################
 782 #
 783 # Collect all non-global variables
 784 #
 785
 786 # Define the universe of supported ISAs
 787 all_isa_list = [ ]
 788 all_gpu_isa_list = [ ]
 789 Export('all_isa_list')
 790 Export('all_gpu_isa_list')
 791
 792 class CpuModel(object):
 793     '''The CpuModel class encapsulates everything the ISA parser needs to
 794     know about a particular CPU model.'''
 795
 796     # Dict of available CPU model objects.  Accessible as CpuModel.dict.
 797     dict = {}
 798
 799     # Constructor.  Automatically adds models to CpuModel.dict.
 800     def __init__(self, name, default=False):
 801         self.name = name           # name of model
 802
 803         # This cpu is enabled by default
 804         self.default = default
 805
 806         # Add self to dict
 807         if name in CpuModel.dict:
 808             raise AttributeError("CpuModel '%s' already registered" % name)
 809         CpuModel.dict[name] = self
 810
 811 Export('CpuModel')
 812
 813 # Sticky variables get saved in the variables file so they persist from
 814 # one invocation to the next (unless overridden, in which case the new
 815 # value becomes sticky).
 816 sticky_vars = Variables(args=ARGUMENTS)
 817 Export('sticky_vars')
 818
 819 # Sticky variables that should be exported
 820 export_vars = []
 821 Export('export_vars')
 822
 823 # For Ruby
 824 all_protocols = []
 825 Export('all_protocols')
 826 protocol_dirs = []
 827 Export('protocol_dirs')
 828 slicc_includes = []
 829 Export('slicc_includes')
 830
 831 # Walk the tree and execute all SConsopts scripts that wil add to the
 832 # above variables
 833 if GetOption('verbose'):
 834     print("Reading SConsopts")
 835 for bdir in [ base_dir ] + extras_dir_list:
 836     if not isdir(bdir):
 837         error("Directory '%s' does not exist." % bdir)
 838     for root, dirs, files in os.walk(bdir):
 839         if 'SConsopts' in files:
 840             if GetOption('verbose'):
 841                 print("Reading", joinpath(root, 'SConsopts'))
 842             SConscript(joinpath(root, 'SConsopts'))
 843
 844 all_isa_list.sort()
 845 all_gpu_isa_list.sort()
 846
 847 sticky_vars.AddVariables(
 848     EnumVariable('TARGET_ISA', 'Target ISA', 'null', all_isa_list),
 849     EnumVariable('TARGET_GPU_ISA', 'Target GPU ISA', 'gcn3', all_gpu_isa_list),
 850     ListVariable('CPU_MODELS', 'CPU models',
 851                  sorted(n for n,m in CpuModel.dict.items() if m.default),
 852                  sorted(CpuModel.dict.keys())),
 853     BoolVariable('EFENCE', 'Link with Electric Fence malloc debugger',
 854                  False),
 855     BoolVariable('USE_SSE2',
 856                  'Compile for SSE2 (-msse2) to get IEEE FP on x86 hosts',
 857                  False),
 858     BoolVariable('USE_POSIX_CLOCK', 'Use POSIX Clocks', have_posix_clock),
 859     BoolVariable('USE_FENV', 'Use <fenv.h> IEEE mode control', have_fenv),
 860     BoolVariable('USE_PNG',  'Enable support for PNG images', have_png),
 861     BoolVariable('USE_KVM', 'Enable hardware virtualized (KVM) CPU models',
 862                  have_kvm),
 863     BoolVariable('USE_TUNTAP',
 864                  'Enable using a tap device to bridge to the host network',
 865                  have_tuntap),
 866     BoolVariable('BUILD_GPU', 'Build the compute-GPU model', False),
 867     EnumVariable('PROTOCOL', 'Coherence protocol for Ruby', 'None',
 868                   all_protocols),
 869     EnumVariable('BACKTRACE_IMPL', 'Post-mortem dump implementation',
 870                  backtrace_impls[-1], backtrace_impls),
 871     ('NUMBER_BITS_PER_SET', 'Max elements in set (default 64)',
 872                  64),
 873     BoolVariable('USE_HDF5', 'Enable the HDF5 support', have_hdf5),
 874     )
 875
 876 # These variables get exported to #defines in config/*.hh (see src/SConscript).
 877 export_vars += ['USE_FENV', 'TARGET_ISA', 'TARGET_GPU_ISA',
 878                 'USE_POSIX_CLOCK', 'USE_KVM', 'USE_TUNTAP', 'PROTOCOL',
 879                 'HAVE_PROTOBUF', 'HAVE_VALGRIND',
 880                 'HAVE_PERF_ATTR_EXCLUDE_HOST', 'USE_PNG',
 881                 'NUMBER_BITS_PER_SET', 'USE_HDF5']
 882
 883 ###################################################
 884 #
 885 # Define a SCons builder for configuration flag headers.
 886 #
 887 ###################################################
 888
 889 # This function generates a config header file that #defines the
 890 # variable symbol to the current variable setting (0 or 1).  The source
 891 # operands are the name of the variable and a Value node containing the
 892 # value of the variable.
 893 def build_config_file(target, source, env):
 894     (variable, value) = [s.get_contents().decode('utf-8') for s in source]
 895     with open(str(target[0].abspath), 'w') as f:
 896         print('#define', variable, value, file=f)
 897     return None
 898
 899 # Combine the two functions into a scons Action object.
 900 config_action = MakeAction(build_config_file, Transform("CONFIG H", 2))
 901
 902 # The emitter munges the source & target node lists to reflect what
 903 # we're really doing.
 904 def config_emitter(target, source, env):
 905     # extract variable name from Builder arg
 906     variable = str(target[0])
 907     # True target is config header file
 908     target = Dir('config').File(variable.lower() + '.hh')
 909     val = env[variable]
 910     if isinstance(val, bool):
 911         # Force value to 0/1
 912         val = int(val)
 913     elif isinstance(val, str):
 914         val = '"' + val + '"'
 915
 916     # Sources are variable name & value (packaged in SCons Value nodes)
 917     return [target], [Value(variable), Value(val)]
 918
 919 config_builder = Builder(emitter=config_emitter, action=config_action)
 920
 921 main.Append(BUILDERS = { 'ConfigFile' : config_builder })
 922
 923 def add_local_rpath(env, *targets):
 924     '''Set up an RPATH for a library which lives in the build directory.
 925
 926     The construction environment variable BIN_RPATH_PREFIX should be set to
 927     the relative path of the build directory starting from the location of the
 928     binary.'''
 929     for target in targets:
 930         target = env.Entry(target)
 931         if not isinstance(target, SCons.Node.FS.Dir):
 932             target = target.dir
 933         relpath = os.path.relpath(target.abspath, env['BUILDDIR'])
 934         components = [
 935             '\\$$ORIGIN',
 936             '${BIN_RPATH_PREFIX}',
 937             relpath
 938         ]
 939         env.Append(RPATH=[env.Literal(os.path.join(*components))])
 940
 941 if sys.platform != "darwin":
 942     main.Append(LINKFLAGS=Split('-z origin'))
 943
 944 main.AddMethod(add_local_rpath, 'AddLocalRPATH')
 945
 946 # builds in ext are shared across all configs in the build root.
 947 ext_dir = Dir('#ext').abspath
 948 ext_build_dirs = []
 949 for root, dirs, files in os.walk(ext_dir):
 950     if 'SConscript' in files:
 951         build_dir = os.path.relpath(root, ext_dir)
 952         ext_build_dirs.append(build_dir)
 953         main.SConscript(joinpath(root, 'SConscript'),
 954                         variant_dir=joinpath(build_root, build_dir))
 955
 956 gdb_xml_dir = joinpath(ext_dir, 'gdb-xml')
 957 Export('gdb_xml_dir')
 958
 959 ###################################################
 960 #
 961 # This builder and wrapper method are used to set up a directory with
 962 # switching headers. Those are headers which are in a generic location and
 963 # that include more specific headers from a directory chosen at build time
 964 # based on the current build settings.
 965 #
 966 ###################################################
 967
 968 def build_switching_header(target, source, env):
 969     path = str(target[0])
 970     subdir = str(source[0])
 971     dp, fp = os.path.split(path)
 972     dp = os.path.relpath(os.path.realpath(dp),
 973                          os.path.realpath(env['BUILDDIR']))
 974     with open(path, 'w') as hdr:
 975         print('#include "%s/%s/%s"' % (dp, subdir, fp), file=hdr)
 976
 977 switching_header_action = MakeAction(build_switching_header,
 978                                      Transform('GENERATE'))
 979
 980 switching_header_builder = Builder(action=switching_header_action,
 981                                    source_factory=Value,
 982                                    single_source=True)
 983
 984 main.Append(BUILDERS = { 'SwitchingHeader': switching_header_builder })
 985
 986 def switching_headers(self, headers, source):
 987     for header in headers:
 988         self.SwitchingHeader(header, source)
 989
 990 main.AddMethod(switching_headers, 'SwitchingHeaders')
 991
 992 ###################################################
 993 #
 994 # Define build environments for selected configurations.
 995 #
 996 ###################################################
 997
 998 for variant_path in variant_paths:
 999     if not GetOption('silent'):
1000         print("Building in", variant_path)
1001
1002     # Make a copy of the build-root environment to use for this config.
1003     env = main.Clone()
1004     env['BUILDDIR'] = variant_path
1005
1006     # variant_dir is the tail component of build path, and is used to
1007     # determine the build parameters (e.g., 'X86')
1008     (build_root, variant_dir) = splitpath(variant_path)
1009
1010     # Set env variables according to the build directory config.
1011     sticky_vars.files = []
1012     # Variables for $BUILD_ROOT/$VARIANT_DIR are stored in
1013     # $BUILD_ROOT/variables/$VARIANT_DIR so you can nuke
1014     # $BUILD_ROOT/$VARIANT_DIR without losing your variables settings.
1015     current_vars_file = joinpath(build_root, 'variables', variant_dir)
1016     if isfile(current_vars_file):
1017         sticky_vars.files.append(current_vars_file)
1018         if not GetOption('silent'):
1019             print("Using saved variables file %s" % current_vars_file)
1020     elif variant_dir in ext_build_dirs:
1021         # Things in ext are built without a variant directory.
1022         continue
1023     else:
1024         # Build dir-specific variables file doesn't exist.
1025
1026         # Make sure the directory is there so we can create it later
1027         opt_dir = dirname(current_vars_file)
1028         if not isdir(opt_dir):
1029             mkdir(opt_dir)
1030
1031         # Get default build variables from source tree.  Variables are
1032         # normally determined by name of $VARIANT_DIR, but can be
1033         # overridden by '--default=' arg on command line.
1034         default = GetOption('default')
1035         opts_dir = Dir('#build_opts').abspath
1036         if default:
1037             default_vars_files = [joinpath(build_root, 'variables', default),
1038                                   joinpath(opts_dir, default)]
1039         else:
1040             default_vars_files = [joinpath(opts_dir, variant_dir)]
1041         existing_files = list(filter(isfile, default_vars_files))
1042         if existing_files:
1043             default_vars_file = existing_files[0]
1044             sticky_vars.files.append(default_vars_file)
1045             print("Variables file %s not found,\n  using defaults in %s"
1046                   % (current_vars_file, default_vars_file))
1047         else:
1048             error("Cannot find variables file %s or default file(s) %s"
1049                   % (current_vars_file, ' or '.join(default_vars_files)))
1050             Exit(1)
1051
1052     # Apply current variable settings to env
1053     sticky_vars.Update(env)
1054
1055     Help('''
1056 Build variables for {dir}:
1057 {help}
1058 '''.format(dir=variant_dir, help=sticky_vars.GenerateHelpText(env)),
1059          append=True)
1060
1061     # Process variable settings.
1062
1063     if not have_fenv and env['USE_FENV']:
1064         warning("<fenv.h> not available; forcing USE_FENV to False in",
1065                 variant_dir + ".")
1066         env['USE_FENV'] = False
1067
1068     if not env['USE_FENV']:
1069         warning("No IEEE FP rounding mode control in", variant_dir + ".\n"
1070                 "FP results may deviate slightly from other platforms.")
1071
1072     if not have_png and env['USE_PNG']:
1073         warning("<png.h> not available; forcing USE_PNG to False in",
1074                 variant_dir + ".")
1075         env['USE_PNG'] = False
1076
1077     if env['USE_PNG']:
1078         env.Append(LIBS=['png'])
1079
1080     if env['EFENCE']:
1081         env.Append(LIBS=['efence'])
1082
1083     if env['USE_KVM']:
1084         if not have_kvm:
1085             warning("Can not enable KVM, host seems to lack KVM support")
1086             env['USE_KVM'] = False
1087         elif not is_isa_kvm_compatible(env['TARGET_ISA']):
1088             print("Info: KVM support disabled due to unsupported host and "
1089                   "target ISA combination")
1090             env['USE_KVM'] = False
1091
1092     if env['USE_TUNTAP']:
1093         if not have_tuntap:
1094             warning("Can't connect EtherTap with a tap device.")
1095             env['USE_TUNTAP'] = False
1096
1097     if env['BUILD_GPU']:
1098         env.Append(CPPDEFINES=['BUILD_GPU'])
1099
1100     # Warn about missing optional functionality
1101     if env['USE_KVM']:
1102         if not main['HAVE_PERF_ATTR_EXCLUDE_HOST']:
1103             warning("perf_event headers lack support for the exclude_host "
1104                     "attribute. KVM instruction counts will be inaccurate.")
1105
1106     # Save sticky variable settings back to current variables file
1107     sticky_vars.Save(current_vars_file, env)
1108
1109     if env['USE_SSE2']:
1110         env.Append(CCFLAGS=['-msse2'])
1111
1112     env.Append(CCFLAGS='$CCFLAGS_EXTRA')
1113     env.Append(LINKFLAGS='$LDFLAGS_EXTRA')
1114
1115     exports=['env']
1116     if main['USE_PYTHON']:
1117         exports.append('marshal_env')
1118
1119     # The src/SConscript file sets up the build rules in 'env' according
1120     # to the configured variables.  It returns a list of environments,
1121     # one for each variant build (debug, opt, etc.)
1122     SConscript('src/SConscript', variant_dir=variant_path, exports=exports)
1123
1124 atexit.register(summarize_warnings)