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 from __future__ import print_function
  79
  80 # Global Python includes
  81 import itertools
  82 import os
  83 import re
  84 import shutil
  85 import subprocess
  86 import sys
  87
  88 from os import mkdir, environ
  89 from os.path import abspath, basename, dirname, expanduser, normpath
  90 from os.path import exists,  isdir, isfile
  91 from os.path import join as joinpath, split as splitpath
  92 from re import match
  93
  94 # SCons includes
  95 import SCons
  96 import SCons.Node
  97 import SCons.Node.FS
  98
  99 from m5.util import compareVersions, readCommand
 100
 101 help_texts = {
 102     "options" : "",
 103     "global_vars" : "",
 104     "local_vars" : ""
 105 }
 106
 107 Export("help_texts")
 108
 109
 110 # There's a bug in scons in that (1) by default, the help texts from
 111 # AddOption() are supposed to be displayed when you type 'scons -h'
 112 # and (2) you can override the help displayed by 'scons -h' using the
 113 # Help() function, but these two features are incompatible: once
 114 # you've overridden the help text using Help(), there's no way to get
 115 # at the help texts from AddOptions.  See:
 116 #     http://scons.tigris.org/issues/show_bug.cgi?id=2356
 117 #     http://scons.tigris.org/issues/show_bug.cgi?id=2611
 118 # This hack lets us extract the help text from AddOptions and
 119 # re-inject it via Help().  Ideally someday this bug will be fixed and
 120 # we can just use AddOption directly.
 121 def AddLocalOption(*args, **kwargs):
 122     col_width = 30
 123
 124     help = "  " + ", ".join(args)
 125     if "help" in kwargs:
 126         length = len(help)
 127         if length >= col_width:
 128             help += "\n" + " " * col_width
 129         else:
 130             help += " " * (col_width - length)
 131         help += kwargs["help"]
 132     help_texts["options"] += help + "\n"
 133
 134     AddOption(*args, **kwargs)
 135
 136 AddLocalOption('--colors', dest='use_colors', action='store_true',
 137                help="Add color to abbreviated scons output")
 138 AddLocalOption('--no-colors', dest='use_colors', action='store_false',
 139                help="Don't add color to abbreviated scons output")
 140 AddLocalOption('--with-cxx-config', dest='with_cxx_config',
 141                action='store_true',
 142                help="Build with support for C++-based configuration")
 143 AddLocalOption('--default', dest='default', type='string', action='store',
 144                help='Override which build_opts file to use for defaults')
 145 AddLocalOption('--ignore-style', dest='ignore_style', action='store_true',
 146                help='Disable style checking hooks')
 147 AddLocalOption('--gold-linker', dest='gold_linker', action='store_true',
 148                help='Use the gold linker')
 149 AddLocalOption('--no-lto', dest='no_lto', action='store_true',
 150                help='Disable Link-Time Optimization for fast')
 151 AddLocalOption('--force-lto', dest='force_lto', action='store_true',
 152                help='Use Link-Time Optimization instead of partial linking' +
 153                     ' when the compiler doesn\'t support using them together.')
 154 AddLocalOption('--update-ref', dest='update_ref', action='store_true',
 155                help='Update test reference outputs')
 156 AddLocalOption('--verbose', dest='verbose', action='store_true',
 157                help='Print full tool command lines')
 158 AddLocalOption('--without-python', dest='without_python',
 159                action='store_true',
 160                help='Build without Python configuration support')
 161 AddLocalOption('--without-tcmalloc', dest='without_tcmalloc',
 162                action='store_true',
 163                help='Disable linking against tcmalloc')
 164 AddLocalOption('--with-ubsan', dest='with_ubsan', action='store_true',
 165                help='Build with Undefined Behavior Sanitizer if available')
 166 AddLocalOption('--with-asan', dest='with_asan', action='store_true',
 167                help='Build with Address Sanitizer if available')
 168 AddLocalOption('--with-systemc-tests', dest='with_systemc_tests',
 169                action='store_true', help='Build systemc tests')
 170
 171 from gem5_scons import Transform, error, warning
 172
 173 if GetOption('no_lto') and GetOption('force_lto'):
 174     error('--no-lto and --force-lto are mutually exclusive')
 175
 176 ########################################################################
 177 #
 178 # Set up the main build environment.
 179 #
 180 ########################################################################
 181
 182 main = Environment()
 183
 184 from gem5_scons.util import get_termcap
 185 termcap = get_termcap()
 186
 187 main_dict_keys = main.Dictionary().keys()
 188
 189 # Check that we have a C/C++ compiler
 190 if not ('CC' in main_dict_keys and 'CXX' in main_dict_keys):
 191     error("No C++ compiler installed (package g++ on Ubuntu and RedHat)")
 192
 193 ###################################################
 194 #
 195 # Figure out which configurations to set up based on the path(s) of
 196 # the target(s).
 197 #
 198 ###################################################
 199
 200 # Find default configuration & binary.
 201 Default(environ.get('M5_DEFAULT_BINARY', 'build/ARM/gem5.debug'))
 202
 203 # helper function: find last occurrence of element in list
 204 def rfind(l, elt, offs = -1):
 205     for i in range(len(l)+offs, 0, -1):
 206         if l[i] == elt:
 207             return i
 208     raise ValueError("element not found")
 209
 210 # Take a list of paths (or SCons Nodes) and return a list with all
 211 # paths made absolute and ~-expanded.  Paths will be interpreted
 212 # relative to the launch directory unless a different root is provided
 213 def makePathListAbsolute(path_list, root=GetLaunchDir()):
 214     return [abspath(joinpath(root, expanduser(str(p))))
 215             for p in path_list]
 216
 217 # Each target must have 'build' in the interior of the path; the
 218 # directory below this will determine the build parameters.  For
 219 # example, for target 'foo/bar/build/X86/arch/x86/blah.do' we
 220 # recognize that X86 specifies the configuration because it
 221 # follow 'build' in the build path.
 222
 223 # The funky assignment to "[:]" is needed to replace the list contents
 224 # in place rather than reassign the symbol to a new list, which
 225 # doesn't work (obviously!).
 226 BUILD_TARGETS[:] = makePathListAbsolute(BUILD_TARGETS)
 227
 228 # Generate a list of the unique build roots and configs that the
 229 # collected targets reference.
 230 variant_paths = []
 231 build_root = None
 232 for t in BUILD_TARGETS:
 233     path_dirs = t.split('/')
 234     try:
 235         build_top = rfind(path_dirs, 'build', -2)
 236     except:
 237         error("No non-leaf 'build' dir found on target path.", t)
 238     this_build_root = joinpath('/',*path_dirs[:build_top+1])
 239     if not build_root:
 240         build_root = this_build_root
 241     else:
 242         if this_build_root != build_root:
 243             error("build targets not under same build root\n"
 244                   "  %s\n  %s" % (build_root, this_build_root))
 245     variant_path = joinpath('/',*path_dirs[:build_top+2])
 246     if variant_path not in variant_paths:
 247         variant_paths.append(variant_path)
 248
 249 # Make sure build_root exists (might not if this is the first build there)
 250 if not isdir(build_root):
 251     mkdir(build_root)
 252 main['BUILDROOT'] = build_root
 253
 254 Export('main')
 255
 256 main.SConsignFile(joinpath(build_root, "sconsign"))
 257
 258 # Default duplicate option is to use hard links, but this messes up
 259 # when you use emacs to edit a file in the target dir, as emacs moves
 260 # file to file~ then copies to file, breaking the link.  Symbolic
 261 # (soft) links work better.
 262 main.SetOption('duplicate', 'soft-copy')
 263
 264 #
 265 # Set up global sticky variables... these are common to an entire build
 266 # tree (not specific to a particular build like X86)
 267 #
 268
 269 global_vars_file = joinpath(build_root, 'variables.global')
 270
 271 global_vars = Variables(global_vars_file, args=ARGUMENTS)
 272
 273 global_vars.AddVariables(
 274     ('CC', 'C compiler', environ.get('CC', main['CC'])),
 275     ('CXX', 'C++ compiler', environ.get('CXX', main['CXX'])),
 276     ('CCFLAGS_EXTRA', 'Extra C and C++ compiler flags', ''),
 277     ('LDFLAGS_EXTRA', 'Extra linker flags', ''),
 278     ('PYTHON_CONFIG', 'Python config binary to use',
 279      [ 'python2.7-config', 'python-config' ]),
 280     ('PROTOC', 'protoc tool', environ.get('PROTOC', 'protoc')),
 281     ('BATCH', 'Use batch pool for build and tests', False),
 282     ('BATCH_CMD', 'Batch pool submission command name', 'qdo'),
 283     ('M5_BUILD_CACHE', 'Cache built objects in this directory', False),
 284     ('EXTRAS', 'Add extra directories to the compilation', '')
 285     )
 286
 287 # Update main environment with values from ARGUMENTS & global_vars_file
 288 global_vars.Update(main)
 289 help_texts["global_vars"] += global_vars.GenerateHelpText(main)
 290
 291 # Save sticky variable settings back to current variables file
 292 global_vars.Save(global_vars_file, main)
 293
 294 # Parse EXTRAS variable to build list of all directories where we're
 295 # look for sources etc.  This list is exported as extras_dir_list.
 296 base_dir = main.srcdir.abspath
 297 if main['EXTRAS']:
 298     extras_dir_list = makePathListAbsolute(main['EXTRAS'].split(':'))
 299 else:
 300     extras_dir_list = []
 301
 302 Export('base_dir')
 303 Export('extras_dir_list')
 304
 305 # the ext directory should be on the #includes path
 306 main.Append(CPPPATH=[Dir('ext')])
 307
 308 # Add shared top-level headers
 309 main.Prepend(CPPPATH=Dir('include'))
 310
 311 if GetOption('verbose'):
 312     def MakeAction(action, string, *args, **kwargs):
 313         return Action(action, *args, **kwargs)
 314 else:
 315     MakeAction = Action
 316     main['CCCOMSTR']        = Transform("CC")
 317     main['CXXCOMSTR']       = Transform("CXX")
 318     main['ASCOMSTR']        = Transform("AS")
 319     main['ARCOMSTR']        = Transform("AR", 0)
 320     main['LINKCOMSTR']      = Transform("LINK", 0)
 321     main['SHLINKCOMSTR']    = Transform("SHLINK", 0)
 322     main['RANLIBCOMSTR']    = Transform("RANLIB", 0)
 323     main['M4COMSTR']        = Transform("M4")
 324     main['SHCCCOMSTR']      = Transform("SHCC")
 325     main['SHCXXCOMSTR']     = Transform("SHCXX")
 326 Export('MakeAction')
 327
 328 # Initialize the Link-Time Optimization (LTO) flags
 329 main['LTO_CCFLAGS'] = []
 330 main['LTO_LDFLAGS'] = []
 331
 332 # According to the readme, tcmalloc works best if the compiler doesn't
 333 # assume that we're using the builtin malloc and friends. These flags
 334 # are compiler-specific, so we need to set them after we detect which
 335 # compiler we're using.
 336 main['TCMALLOC_CCFLAGS'] = []
 337
 338 CXX_version = readCommand([main['CXX'],'--version'], exception=False)
 339 CXX_V = readCommand([main['CXX'],'-V'], exception=False)
 340
 341 main['GCC'] = CXX_version and CXX_version.find('g++') >= 0
 342 main['CLANG'] = CXX_version and CXX_version.find('clang') >= 0
 343 if main['GCC'] + main['CLANG'] > 1:
 344     error('Two compilers enabled at once?')
 345
 346 # Set up default C++ compiler flags
 347 if main['GCC'] or main['CLANG']:
 348     # As gcc and clang share many flags, do the common parts here
 349     main.Append(CCFLAGS=['-pipe'])
 350     main.Append(CCFLAGS=['-fno-strict-aliasing'])
 351     # Enable -Wall and -Wextra and then disable the few warnings that
 352     # we consistently violate
 353     main.Append(CCFLAGS=['-Wall', '-Wundef', '-Wextra',
 354                          '-Wno-sign-compare', '-Wno-unused-parameter'])
 355     # We always compile using C++11
 356     main.Append(CXXFLAGS=['-std=c++11'])
 357     if sys.platform.startswith('freebsd'):
 358         main.Append(CCFLAGS=['-I/usr/local/include'])
 359         main.Append(CXXFLAGS=['-I/usr/local/include'])
 360
 361     main.Append(LINKFLAGS='-Wl,--as-needed')
 362     main['FILTER_PSHLINKFLAGS'] = lambda x: str(x).replace(' -shared', '')
 363     main['PSHLINKFLAGS'] = main.subst('${FILTER_PSHLINKFLAGS(SHLINKFLAGS)}')
 364     if GetOption('gold_linker'):
 365         main.Append(LINKFLAGS='-fuse-ld=gold')
 366     main['PLINKFLAGS'] = main.get('LINKFLAGS')
 367     shared_partial_flags = ['-r', '-nostdlib']
 368     main.Append(PSHLINKFLAGS=shared_partial_flags)
 369     main.Append(PLINKFLAGS=shared_partial_flags)
 370
 371     # Treat warnings as errors but white list some warnings that we
 372     # want to allow (e.g., deprecation warnings).
 373     main.Append(CCFLAGS=['-Werror',
 374                          '-Wno-error=deprecated-declarations',
 375                          '-Wno-error=deprecated',
 376                         ])
 377 else:
 378     error('\n'.join((
 379           "Don't know what compiler options to use for your compiler.",
 380           "compiler: " + main['CXX'],
 381           "version: " + CXX_version.replace('\n', '<nl>') if
 382                 CXX_version else 'COMMAND NOT FOUND!',
 383           "If you're trying to use a compiler other than GCC",
 384           "or clang, there appears to be something wrong with your",
 385           "environment.",
 386           "",
 387           "If you are trying to use a compiler other than those listed",
 388           "above you will need to ease fix SConstruct and ",
 389           "src/SConscript to support that compiler.")))
 390
 391 if main['GCC']:
 392     # Check for a supported version of gcc. >= 4.8 is chosen for its
 393     # level of c++11 support. See
 394     # http://gcc.gnu.org/projects/cxx0x.html for details.
 395     gcc_version = readCommand([main['CXX'], '-dumpversion'], exception=False)
 396     if compareVersions(gcc_version, "4.8") < 0:
 397         error('gcc version 4.8 or newer required.\n'
 398               'Installed version:', gcc_version)
 399         Exit(1)
 400
 401     main['GCC_VERSION'] = gcc_version
 402
 403     if compareVersions(gcc_version, '4.9') >= 0:
 404         # Incremental linking with LTO is currently broken in gcc versions
 405         # 4.9 and above. A version where everything works completely hasn't
 406         # yet been identified.
 407         #
 408         # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67548
 409         main['BROKEN_INCREMENTAL_LTO'] = True
 410     if compareVersions(gcc_version, '6.0') >= 0:
 411         # gcc versions 6.0 and greater accept an -flinker-output flag which
 412         # selects what type of output the linker should generate. This is
 413         # necessary for incremental lto to work, but is also broken in
 414         # current versions of gcc. It may not be necessary in future
 415         # versions. We add it here since it might be, and as a reminder that
 416         # it exists. It's excluded if lto is being forced.
 417         #
 418         # https://gcc.gnu.org/gcc-6/changes.html
 419         # https://gcc.gnu.org/ml/gcc-patches/2015-11/msg03161.html
 420         # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69866
 421         if not GetOption('force_lto'):
 422             main.Append(PSHLINKFLAGS='-flinker-output=rel')
 423             main.Append(PLINKFLAGS='-flinker-output=rel')
 424
 425     disable_lto = GetOption('no_lto')
 426     if not disable_lto and main.get('BROKEN_INCREMENTAL_LTO', False) and \
 427             not GetOption('force_lto'):
 428         warning('Your compiler doesn\'t support incremental linking and lto '
 429                 'at the same time, so lto is being disabled. To force lto on '
 430                 'anyway, use the --force-lto option. That will disable '
 431                 'partial linking.')
 432         disable_lto = True
 433
 434     # Add the appropriate Link-Time Optimization (LTO) flags
 435     # unless LTO is explicitly turned off. Note that these flags
 436     # are only used by the fast target.
 437     if not disable_lto:
 438         # Pass the LTO flag when compiling to produce GIMPLE
 439         # output, we merely create the flags here and only append
 440         # them later
 441         main['LTO_CCFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
 442
 443         # Use the same amount of jobs for LTO as we are running
 444         # scons with
 445         main['LTO_LDFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
 446
 447     main.Append(TCMALLOC_CCFLAGS=['-fno-builtin-malloc', '-fno-builtin-calloc',
 448                                   '-fno-builtin-realloc', '-fno-builtin-free'])
 449
 450 elif main['CLANG']:
 451     # Check for a supported version of clang, >= 3.1 is needed to
 452     # support similar features as gcc 4.8. See
 453     # http://clang.llvm.org/cxx_status.html for details
 454     clang_version_re = re.compile(".* version (\d+\.\d+)")
 455     clang_version_match = clang_version_re.search(CXX_version)
 456     if (clang_version_match):
 457         clang_version = clang_version_match.groups()[0]
 458         if compareVersions(clang_version, "3.1") < 0:
 459             error('clang version 3.1 or newer required.\n'
 460                   'Installed version:', clang_version)
 461     else:
 462         error('Unable to determine clang version.')
 463
 464     # clang has a few additional warnings that we disable, extraneous
 465     # parantheses are allowed due to Ruby's printing of the AST,
 466     # finally self assignments are allowed as the generated CPU code
 467     # is relying on this
 468     main.Append(CCFLAGS=['-Wno-parentheses',
 469                          '-Wno-self-assign',
 470                          # Some versions of libstdc++ (4.8?) seem to
 471                          # use struct hash and class hash
 472                          # interchangeably.
 473                          '-Wno-mismatched-tags',
 474                          ])
 475
 476     main.Append(TCMALLOC_CCFLAGS=['-fno-builtin'])
 477
 478     # On Mac OS X/Darwin we need to also use libc++ (part of XCode) as
 479     # opposed to libstdc++, as the later is dated.
 480     if sys.platform == "darwin":
 481         main.Append(CXXFLAGS=['-stdlib=libc++'])
 482         main.Append(LIBS=['c++'])
 483
 484     # On FreeBSD we need libthr.
 485     if sys.platform.startswith('freebsd'):
 486         main.Append(LIBS=['thr'])
 487
 488 # Add sanitizers flags
 489 sanitizers=[]
 490 if GetOption('with_ubsan'):
 491     # Only gcc >= 4.9 supports UBSan, so check both the version
 492     # and the command-line option before adding the compiler and
 493     # linker flags.
 494     if not main['GCC'] or compareVersions(main['GCC_VERSION'], '4.9') >= 0:
 495         sanitizers.append('undefined')
 496 if GetOption('with_asan'):
 497     # Available for gcc >= 4.8 or llvm >= 3.1 both a requirement
 498     # by the build system
 499     sanitizers.append('address')
 500     suppressions_file = Dir('util').File('lsan-suppressions').get_abspath()
 501     suppressions_opt = 'suppressions=%s' % suppressions_file
 502     main['ENV']['LSAN_OPTIONS'] = ':'.join([suppressions_opt,
 503                                             'print_suppressions=0'])
 504     print()
 505     warning('To suppress false positive leaks, set the LSAN_OPTIONS '
 506             'environment variable to "%s" when running gem5' %
 507             suppressions_opt)
 508     warning('LSAN_OPTIONS=suppressions=%s' % suppressions_opt)
 509     print()
 510 if sanitizers:
 511     sanitizers = ','.join(sanitizers)
 512     if main['GCC'] or main['CLANG']:
 513         main.Append(CCFLAGS=['-fsanitize=%s' % sanitizers,
 514                              '-fno-omit-frame-pointer'],
 515                     LINKFLAGS='-fsanitize=%s' % sanitizers)
 516     else:
 517         warning("Don't know how to enable %s sanitizer(s) for your "
 518                 "compiler." % sanitizers)
 519
 520 # Set up common yacc/bison flags (needed for Ruby)
 521 main['YACCFLAGS'] = '-d'
 522 main['YACCHXXFILESUFFIX'] = '.hh'
 523
 524 # Do this after we save setting back, or else we'll tack on an
 525 # extra 'qdo' every time we run scons.
 526 if main['BATCH']:
 527     main['CC']     = main['BATCH_CMD'] + ' ' + main['CC']
 528     main['CXX']    = main['BATCH_CMD'] + ' ' + main['CXX']
 529     main['AS']     = main['BATCH_CMD'] + ' ' + main['AS']
 530     main['AR']     = main['BATCH_CMD'] + ' ' + main['AR']
 531     main['RANLIB'] = main['BATCH_CMD'] + ' ' + main['RANLIB']
 532
 533 if sys.platform == 'cygwin':
 534     # cygwin has some header file issues...
 535     main.Append(CCFLAGS=["-Wno-uninitialized"])
 536
 537
 538 have_pkg_config = readCommand(['pkg-config', '--version'], exception='')
 539
 540 # Check for the protobuf compiler
 541 try:
 542     main['HAVE_PROTOC'] = True
 543     protoc_version = readCommand([main['PROTOC'], '--version']).split()
 544
 545     # First two words should be "libprotoc x.y.z"
 546     if len(protoc_version) < 2 or protoc_version[0] != 'libprotoc':
 547         warning('Protocol buffer compiler (protoc) not found.\n'
 548                 'Please install protobuf-compiler for tracing support.')
 549         main['HAVE_PROTOC'] = False
 550     else:
 551         # Based on the availability of the compress stream wrappers,
 552         # require 2.1.0
 553         min_protoc_version = '2.1.0'
 554         if compareVersions(protoc_version[1], min_protoc_version) < 0:
 555             warning('protoc version', min_protoc_version,
 556                     'or newer required.\n'
 557                     'Installed version:', protoc_version[1])
 558             main['HAVE_PROTOC'] = False
 559         else:
 560             # Attempt to determine the appropriate include path and
 561             # library path using pkg-config, that means we also need to
 562             # check for pkg-config. Note that it is possible to use
 563             # protobuf without the involvement of pkg-config. Later on we
 564             # check go a library config check and at that point the test
 565             # will fail if libprotobuf cannot be found.
 566             if have_pkg_config:
 567                 try:
 568                     # Attempt to establish what linking flags to add for
 569                     # protobuf
 570                     # using pkg-config
 571                     main.ParseConfig(
 572                             'pkg-config --cflags --libs-only-L protobuf')
 573                 except:
 574                     warning('pkg-config could not get protobuf flags.')
 575 except Exception as e:
 576     warning('While checking protoc version:', str(e))
 577     main['HAVE_PROTOC'] = False
 578
 579 # Check for 'timeout' from GNU coreutils. If present, regressions will
 580 # be run with a time limit. We require version 8.13 since we rely on
 581 # support for the '--foreground' option.
 582 if sys.platform.startswith('freebsd'):
 583     timeout_lines = readCommand(['gtimeout', '--version'],
 584                                 exception='').splitlines()
 585 else:
 586     timeout_lines = readCommand(['timeout', '--version'],
 587                                 exception='').splitlines()
 588 # Get the first line and tokenize it
 589 timeout_version = timeout_lines[0].split() if timeout_lines else []
 590 main['TIMEOUT'] =  timeout_version and \
 591     compareVersions(timeout_version[-1], '8.13') >= 0
 592
 593 # Add a custom Check function to test for structure members.
 594 def CheckMember(context, include, decl, member, include_quotes="<>"):
 595     context.Message("Checking for member %s in %s..." %
 596                     (member, decl))
 597     text = """
 598 #include %(header)s
 599 int main(){
 600   %(decl)s test;
 601   (void)test.%(member)s;
 602   return 0;
 603 };
 604 """ % { "header" : include_quotes[0] + include + include_quotes[1],
 605         "decl" : decl,
 606         "member" : member,
 607         }
 608
 609     ret = context.TryCompile(text, extension=".cc")
 610     context.Result(ret)
 611     return ret
 612
 613 # Platform-specific configuration.  Note again that we assume that all
 614 # builds under a given build root run on the same host platform.
 615 conf = Configure(main,
 616                  conf_dir = joinpath(build_root, '.scons_config'),
 617                  log_file = joinpath(build_root, 'scons_config.log'),
 618                  custom_tests = {
 619         'CheckMember' : CheckMember,
 620         })
 621
 622 # Check if we should compile a 64 bit binary on Mac OS X/Darwin
 623 try:
 624     import platform
 625     uname = platform.uname()
 626     if uname[0] == 'Darwin' and compareVersions(uname[2], '9.0.0') >= 0:
 627         if int(readCommand('sysctl -n hw.cpu64bit_capable')[0]):
 628             main.Append(CCFLAGS=['-arch', 'x86_64'])
 629             main.Append(CFLAGS=['-arch', 'x86_64'])
 630             main.Append(LINKFLAGS=['-arch', 'x86_64'])
 631             main.Append(ASFLAGS=['-arch', 'x86_64'])
 632 except:
 633     pass
 634
 635 # Recent versions of scons substitute a "Null" object for Configure()
 636 # when configuration isn't necessary, e.g., if the "--help" option is
 637 # present.  Unfortuantely this Null object always returns false,
 638 # breaking all our configuration checks.  We replace it with our own
 639 # more optimistic null object that returns True instead.
 640 if not conf:
 641     def NullCheck(*args, **kwargs):
 642         return True
 643
 644     class NullConf:
 645         def __init__(self, env):
 646             self.env = env
 647         def Finish(self):
 648             return self.env
 649         def __getattr__(self, mname):
 650             return NullCheck
 651
 652     conf = NullConf(main)
 653
 654 # Cache build files in the supplied directory.
 655 if main['M5_BUILD_CACHE']:
 656     print('Using build cache located at', main['M5_BUILD_CACHE'])
 657     CacheDir(main['M5_BUILD_CACHE'])
 658
 659 main['USE_PYTHON'] = not GetOption('without_python')
 660 if main['USE_PYTHON']:
 661     # Find Python include and library directories for embedding the
 662     # interpreter. We rely on python-config to resolve the appropriate
 663     # includes and linker flags. ParseConfig does not seem to understand
 664     # the more exotic linker flags such as -Xlinker and -export-dynamic so
 665     # we add them explicitly below. If you want to link in an alternate
 666     # version of python, see above for instructions on how to invoke
 667     # scons with the appropriate PATH set.
 668
 669     python_config = main.Detect(main['PYTHON_CONFIG'])
 670     if python_config is None:
 671         error("Can't find a suitable python-config, tried %s" % \
 672               main['PYTHON_CONFIG'])
 673
 674     print("Info: Using Python config: %s" % (python_config, ))
 675     py_includes = readCommand([python_config, '--includes'],
 676                               exception='').split()
 677     py_includes = list(filter(
 678         lambda s: match(r'.*\/include\/.*',s), py_includes))
 679     # Strip the -I from the include folders before adding them to the
 680     # CPPPATH
 681     py_includes = list(map(
 682         lambda s: s[2:] if s.startswith('-I') else s, py_includes))
 683     main.Append(CPPPATH=py_includes)
 684
 685     # Read the linker flags and split them into libraries and other link
 686     # flags. The libraries are added later through the call the CheckLib.
 687     py_ld_flags = readCommand([python_config, '--ldflags'],
 688         exception='').split()
 689     py_libs = []
 690     for lib in py_ld_flags:
 691          if not lib.startswith('-l'):
 692              main.Append(LINKFLAGS=[lib])
 693          else:
 694              lib = lib[2:]
 695              if lib not in py_libs:
 696                  py_libs.append(lib)
 697
 698     # verify that this stuff works
 699     if not conf.CheckHeader('Python.h', '<>'):
 700         error("Check failed for Python.h header in",
 701                 ' '.join(py_includes), "\n"
 702               "Two possible reasons:\n"
 703               "1. Python headers are not installed (You can install the "
 704               "package python-dev on Ubuntu and RedHat)\n"
 705               "2. SCons is using a wrong C compiler. This can happen if "
 706               "CC has the wrong value.\n"
 707               "CC = %s" % main['CC'])
 708
 709     for lib in py_libs:
 710         if not conf.CheckLib(lib):
 711             error("Can't find library %s required by python." % lib)
 712
 713 # On Solaris you need to use libsocket for socket ops
 714 if not conf.CheckLibWithHeader(None, 'sys/socket.h', 'C++', 'accept(0,0,0);'):
 715    if not conf.CheckLibWithHeader('socket', 'sys/socket.h',
 716                                   'C++', 'accept(0,0,0);'):
 717        error("Can't find library with socket calls (e.g. accept()).")
 718
 719 # Check for zlib.  If the check passes, libz will be automatically
 720 # added to the LIBS environment variable.
 721 if not conf.CheckLibWithHeader('z', 'zlib.h', 'C++','zlibVersion();'):
 722     error('Did not find needed zlib compression library '
 723           'and/or zlib.h header file.\n'
 724           'Please install zlib and try again.')
 725
 726 # If we have the protobuf compiler, also make sure we have the
 727 # development libraries. If the check passes, libprotobuf will be
 728 # automatically added to the LIBS environment variable. After
 729 # this, we can use the HAVE_PROTOBUF flag to determine if we have
 730 # got both protoc and libprotobuf available.
 731 main['HAVE_PROTOBUF'] = main['HAVE_PROTOC'] and \
 732     conf.CheckLibWithHeader('protobuf', 'google/protobuf/message.h',
 733                             'C++', 'GOOGLE_PROTOBUF_VERIFY_VERSION;')
 734
 735 # Valgrind gets much less confused if you tell it when you're using
 736 # alternative stacks.
 737 main['HAVE_VALGRIND'] = conf.CheckCHeader('valgrind/valgrind.h')
 738
 739 # If we have the compiler but not the library, print another warning.
 740 if main['HAVE_PROTOC'] and not main['HAVE_PROTOBUF']:
 741     warning('Did not find protocol buffer library and/or headers.\n'
 742             'Please install libprotobuf-dev for tracing support.')
 743
 744 # Check for librt.
 745 have_posix_clock = \
 746     conf.CheckLibWithHeader(None, 'time.h', 'C',
 747                             'clock_nanosleep(0,0,NULL,NULL);') or \
 748     conf.CheckLibWithHeader('rt', 'time.h', 'C',
 749                             'clock_nanosleep(0,0,NULL,NULL);')
 750
 751 have_posix_timers = \
 752     conf.CheckLibWithHeader([None, 'rt'], [ 'time.h', 'signal.h' ], 'C',
 753                             'timer_create(CLOCK_MONOTONIC, NULL, NULL);')
 754
 755 if not GetOption('without_tcmalloc'):
 756     if conf.CheckLib('tcmalloc'):
 757         main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
 758     elif conf.CheckLib('tcmalloc_minimal'):
 759         main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
 760     else:
 761         warning("You can get a 12% performance improvement by "
 762                 "installing tcmalloc (libgoogle-perftools-dev package "
 763                 "on Ubuntu or RedHat).")
 764
 765
 766 # Detect back trace implementations. The last implementation in the
 767 # list will be used by default.
 768 backtrace_impls = [ "none" ]
 769
 770 backtrace_checker = 'char temp;' + \
 771     ' backtrace_symbols_fd((void*)&temp, 0, 0);'
 772 if conf.CheckLibWithHeader(None, 'execinfo.h', 'C', backtrace_checker):
 773     backtrace_impls.append("glibc")
 774 elif conf.CheckLibWithHeader('execinfo', 'execinfo.h', 'C',
 775                              backtrace_checker):
 776     # NetBSD and FreeBSD need libexecinfo.
 777     backtrace_impls.append("glibc")
 778     main.Append(LIBS=['execinfo'])
 779
 780 if backtrace_impls[-1] == "none":
 781     default_backtrace_impl = "none"
 782     warning("No suitable back trace implementation found.")
 783
 784 if not have_posix_clock:
 785     warning("Can't find library for POSIX clocks.")
 786
 787 # Check for <fenv.h> (C99 FP environment control)
 788 have_fenv = conf.CheckHeader('fenv.h', '<>')
 789 if not have_fenv:
 790     warning("Header file <fenv.h> not found.\n"
 791             "This host has no IEEE FP rounding mode control.")
 792
 793 # Check for <png.h> (libpng library needed if wanting to dump
 794 # frame buffer image in png format)
 795 have_png = conf.CheckHeader('png.h', '<>')
 796 if not have_png:
 797     warning("Header file <png.h> not found.\n"
 798             "This host has no libpng library.\n"
 799             "Disabling support for PNG framebuffers.")
 800
 801 # Check if we should enable KVM-based hardware virtualization. The API
 802 # we rely on exists since version 2.6.36 of the kernel, but somehow
 803 # the KVM_API_VERSION does not reflect the change. We test for one of
 804 # the types as a fall back.
 805 have_kvm = conf.CheckHeader('linux/kvm.h', '<>')
 806 if not have_kvm:
 807     print("Info: Compatible header file <linux/kvm.h> not found, "
 808           "disabling KVM support.")
 809
 810 # Check if the TUN/TAP driver is available.
 811 have_tuntap = conf.CheckHeader('linux/if_tun.h', '<>')
 812 if not have_tuntap:
 813     print("Info: Compatible header file <linux/if_tun.h> not found.")
 814
 815 # x86 needs support for xsave. We test for the structure here since we
 816 # won't be able to run new tests by the time we know which ISA we're
 817 # targeting.
 818 have_kvm_xsave = conf.CheckTypeSize('struct kvm_xsave',
 819                                     '#include <linux/kvm.h>') != 0
 820
 821 # Check if the requested target ISA is compatible with the host
 822 def is_isa_kvm_compatible(isa):
 823     try:
 824         import platform
 825         host_isa = platform.machine()
 826     except:
 827         warning("Failed to determine host ISA.")
 828         return False
 829
 830     if not have_posix_timers:
 831         warning("Can not enable KVM, host seems to lack support "
 832                 "for POSIX timers")
 833         return False
 834
 835     if isa == "arm":
 836         return host_isa in ( "armv7l", "aarch64" )
 837     elif isa == "x86":
 838         if host_isa != "x86_64":
 839             return False
 840
 841         if not have_kvm_xsave:
 842             warning("KVM on x86 requires xsave support in kernel headers.")
 843             return False
 844
 845         return True
 846     else:
 847         return False
 848
 849
 850 # Check if the exclude_host attribute is available. We want this to
 851 # get accurate instruction counts in KVM.
 852 main['HAVE_PERF_ATTR_EXCLUDE_HOST'] = conf.CheckMember(
 853     'linux/perf_event.h', 'struct perf_event_attr', 'exclude_host')
 854
 855 def check_hdf5():
 856     return \
 857         conf.CheckLibWithHeader('hdf5', 'hdf5.h', 'C',
 858                                 'H5Fcreate("", 0, 0, 0);') and \
 859         conf.CheckLibWithHeader('hdf5_cpp', 'H5Cpp.h', 'C++',
 860                                 'H5::H5File("", 0);')
 861
 862 def check_hdf5_pkg(name):
 863     print("Checking for %s using pkg-config..." % name, end="")
 864     if not have_pkg_config:
 865         print(" pkg-config not found")
 866         return False
 867
 868     try:
 869         main.ParseConfig('pkg-config --cflags-only-I --libs-only-L %s' % name)
 870         print(" yes")
 871         return True
 872     except:
 873         print(" no")
 874         return False
 875
 876 # Check if there is a pkg-config configuration for hdf5. If we find
 877 # it, setup the environment to enable linking and header inclusion. We
 878 # don't actually try to include any headers or link with hdf5 at this
 879 # stage.
 880 if not check_hdf5_pkg('hdf5-serial'):
 881     check_hdf5_pkg('hdf5')
 882
 883 # Check if the HDF5 libraries can be found. This check respects the
 884 # include path and library path provided by pkg-config. We perform
 885 # this check even if there isn't a pkg-config configuration for hdf5
 886 # since some installations don't use pkg-config.
 887 have_hdf5 = check_hdf5()
 888 if not have_hdf5:
 889     print("Warning: Couldn't find any HDF5 C++ libraries. Disabling")
 890     print("         HDF5 support.")
 891
 892 ######################################################################
 893 #
 894 # Finish the configuration
 895 #
 896 main = conf.Finish()
 897
 898 ######################################################################
 899 #
 900 # Collect all non-global variables
 901 #
 902
 903 # Define the universe of supported ISAs
 904 all_isa_list = [ ]
 905 all_gpu_isa_list = [ ]
 906 Export('all_isa_list')
 907 Export('all_gpu_isa_list')
 908
 909 class CpuModel(object):
 910     '''The CpuModel class encapsulates everything the ISA parser needs to
 911     know about a particular CPU model.'''
 912
 913     # Dict of available CPU model objects.  Accessible as CpuModel.dict.
 914     dict = {}
 915
 916     # Constructor.  Automatically adds models to CpuModel.dict.
 917     def __init__(self, name, default=False):
 918         self.name = name           # name of model
 919
 920         # This cpu is enabled by default
 921         self.default = default
 922
 923         # Add self to dict
 924         if name in CpuModel.dict:
 925             raise AttributeError("CpuModel '%s' already registered" % name)
 926         CpuModel.dict[name] = self
 927
 928 Export('CpuModel')
 929
 930 # Sticky variables get saved in the variables file so they persist from
 931 # one invocation to the next (unless overridden, in which case the new
 932 # value becomes sticky).
 933 sticky_vars = Variables(args=ARGUMENTS)
 934 Export('sticky_vars')
 935
 936 # Sticky variables that should be exported
 937 export_vars = []
 938 Export('export_vars')
 939
 940 # For Ruby
 941 all_protocols = []
 942 Export('all_protocols')
 943 protocol_dirs = []
 944 Export('protocol_dirs')
 945 slicc_includes = []
 946 Export('slicc_includes')
 947
 948 # Walk the tree and execute all SConsopts scripts that wil add to the
 949 # above variables
 950 if GetOption('verbose'):
 951     print("Reading SConsopts")
 952 for bdir in [ base_dir ] + extras_dir_list:
 953     if not isdir(bdir):
 954         error("Directory '%s' does not exist." % bdir)
 955     for root, dirs, files in os.walk(bdir):
 956         if 'SConsopts' in files:
 957             if GetOption('verbose'):
 958                 print("Reading", joinpath(root, 'SConsopts'))
 959             SConscript(joinpath(root, 'SConsopts'))
 960
 961 all_isa_list.sort()
 962 all_gpu_isa_list.sort()
 963
 964 sticky_vars.AddVariables(
 965     EnumVariable('TARGET_ISA', 'Target ISA', 'alpha', all_isa_list),
 966     EnumVariable('TARGET_GPU_ISA', 'Target GPU ISA', 'hsail', all_gpu_isa_list),
 967     ListVariable('CPU_MODELS', 'CPU models',
 968                  sorted(n for n,m in CpuModel.dict.items() if m.default),
 969                  sorted(CpuModel.dict.keys())),
 970     BoolVariable('EFENCE', 'Link with Electric Fence malloc debugger',
 971                  False),
 972     BoolVariable('USE_SSE2',
 973                  'Compile for SSE2 (-msse2) to get IEEE FP on x86 hosts',
 974                  False),
 975     BoolVariable('USE_POSIX_CLOCK', 'Use POSIX Clocks', have_posix_clock),
 976     BoolVariable('USE_FENV', 'Use <fenv.h> IEEE mode control', have_fenv),
 977     BoolVariable('USE_PNG',  'Enable support for PNG images', have_png),
 978     BoolVariable('CP_ANNOTATE', 'Enable critical path annotation capability',
 979                  False),
 980     BoolVariable('USE_KVM', 'Enable hardware virtualized (KVM) CPU models',
 981                  have_kvm),
 982     BoolVariable('USE_TUNTAP',
 983                  'Enable using a tap device to bridge to the host network',
 984                  have_tuntap),
 985     BoolVariable('BUILD_GPU', 'Build the compute-GPU model', False),
 986     EnumVariable('PROTOCOL', 'Coherence protocol for Ruby', 'None',
 987                   all_protocols),
 988     EnumVariable('BACKTRACE_IMPL', 'Post-mortem dump implementation',
 989                  backtrace_impls[-1], backtrace_impls),
 990     ('NUMBER_BITS_PER_SET', 'Max elements in set (default 64)',
 991                  64),
 992     BoolVariable('USE_HDF5', 'Enable the HDF5 support', have_hdf5),
 993     )
 994
 995 # These variables get exported to #defines in config/*.hh (see src/SConscript).
 996 export_vars += ['USE_FENV', 'TARGET_ISA', 'TARGET_GPU_ISA', 'CP_ANNOTATE',
 997                 'USE_POSIX_CLOCK', 'USE_KVM', 'USE_TUNTAP', 'PROTOCOL',
 998                 'HAVE_PROTOBUF', 'HAVE_VALGRIND',
 999                 'HAVE_PERF_ATTR_EXCLUDE_HOST', 'USE_PNG',
1000                 'NUMBER_BITS_PER_SET', 'USE_HDF5']
1001
1002 ###################################################
1003 #
1004 # Define a SCons builder for configuration flag headers.
1005 #
1006 ###################################################
1007
1008 # This function generates a config header file that #defines the
1009 # variable symbol to the current variable setting (0 or 1).  The source
1010 # operands are the name of the variable and a Value node containing the
1011 # value of the variable.
1012 def build_config_file(target, source, env):
1013     (variable, value) = [s.get_contents().decode('utf-8') for s in source]
1014     with open(str(target[0]), 'w') as f:
1015         print('#define', variable, value, file=f)
1016     return None
1017
1018 # Combine the two functions into a scons Action object.
1019 config_action = MakeAction(build_config_file, Transform("CONFIG H", 2))
1020
1021 # The emitter munges the source & target node lists to reflect what
1022 # we're really doing.
1023 def config_emitter(target, source, env):
1024     # extract variable name from Builder arg
1025     variable = str(target[0])
1026     # True target is config header file
1027     target = joinpath('config', variable.lower() + '.hh')
1028     val = env[variable]
1029     if isinstance(val, bool):
1030         # Force value to 0/1
1031         val = int(val)
1032     elif isinstance(val, str):
1033         val = '"' + val + '"'
1034
1035     # Sources are variable name & value (packaged in SCons Value nodes)
1036     return ([target], [Value(variable), Value(val)])
1037
1038 config_builder = Builder(emitter = config_emitter, action = config_action)
1039
1040 main.Append(BUILDERS = { 'ConfigFile' : config_builder })
1041
1042 ###################################################
1043 #
1044 # Builders for static and shared partially linked object files.
1045 #
1046 ###################################################
1047
1048 partial_static_builder = Builder(action=SCons.Defaults.LinkAction,
1049                                  src_suffix='$OBJSUFFIX',
1050                                  src_builder=['StaticObject', 'Object'],
1051                                  LINKFLAGS='$PLINKFLAGS',
1052                                  LIBS='')
1053
1054 def partial_shared_emitter(target, source, env):
1055     for tgt in target:
1056         tgt.attributes.shared = 1
1057     return (target, source)
1058 partial_shared_builder = Builder(action=SCons.Defaults.ShLinkAction,
1059                                  emitter=partial_shared_emitter,
1060                                  src_suffix='$SHOBJSUFFIX',
1061                                  src_builder='SharedObject',
1062                                  SHLINKFLAGS='$PSHLINKFLAGS',
1063                                  LIBS='')
1064
1065 main.Append(BUILDERS = { 'PartialShared' : partial_shared_builder,
1066                          'PartialStatic' : partial_static_builder })
1067
1068 def add_local_rpath(env, *targets):
1069     '''Set up an RPATH for a library which lives in the build directory.
1070
1071     The construction environment variable BIN_RPATH_PREFIX should be set to
1072     the relative path of the build directory starting from the location of the
1073     binary.'''
1074     for target in targets:
1075         target = env.Entry(target)
1076         if not isinstance(target, SCons.Node.FS.Dir):
1077             target = target.dir
1078         relpath = os.path.relpath(target.abspath, env['BUILDDIR'])
1079         components = [
1080             '\\$$ORIGIN',
1081             '${BIN_RPATH_PREFIX}',
1082             relpath
1083         ]
1084         env.Append(RPATH=[env.Literal(os.path.join(*components))])
1085
1086 if sys.platform != "darwin":
1087     main.Append(LINKFLAGS=Split('-z origin'))
1088
1089 main.AddMethod(add_local_rpath, 'AddLocalRPATH')
1090
1091 # builds in ext are shared across all configs in the build root.
1092 ext_dir = abspath(joinpath(str(main.root), 'ext'))
1093 ext_build_dirs = []
1094 for root, dirs, files in os.walk(ext_dir):
1095     if 'SConscript' in files:
1096         build_dir = os.path.relpath(root, ext_dir)
1097         ext_build_dirs.append(build_dir)
1098         main.SConscript(joinpath(root, 'SConscript'),
1099                         variant_dir=joinpath(build_root, build_dir))
1100
1101 gdb_xml_dir = joinpath(ext_dir, 'gdb-xml')
1102 Export('gdb_xml_dir')
1103
1104 main.Prepend(CPPPATH=Dir('ext/pybind11/include/'))
1105
1106 ###################################################
1107 #
1108 # This builder and wrapper method are used to set up a directory with
1109 # switching headers. Those are headers which are in a generic location and
1110 # that include more specific headers from a directory chosen at build time
1111 # based on the current build settings.
1112 #
1113 ###################################################
1114
1115 def build_switching_header(target, source, env):
1116     path = str(target[0])
1117     subdir = str(source[0])
1118     dp, fp = os.path.split(path)
1119     dp = os.path.relpath(os.path.realpath(dp),
1120                          os.path.realpath(env['BUILDDIR']))
1121     with open(path, 'w') as hdr:
1122         print('#include "%s/%s/%s"' % (dp, subdir, fp), file=hdr)
1123
1124 switching_header_action = MakeAction(build_switching_header,
1125                                      Transform('GENERATE'))
1126
1127 switching_header_builder = Builder(action=switching_header_action,
1128                                    source_factory=Value,
1129                                    single_source=True)
1130
1131 main.Append(BUILDERS = { 'SwitchingHeader': switching_header_builder })
1132
1133 def switching_headers(self, headers, source):
1134     for header in headers:
1135         self.SwitchingHeader(header, source)
1136
1137 main.AddMethod(switching_headers, 'SwitchingHeaders')
1138
1139 ###################################################
1140 #
1141 # Define build environments for selected configurations.
1142 #
1143 ###################################################
1144
1145 for variant_path in variant_paths:
1146     if not GetOption('silent'):
1147         print("Building in", variant_path)
1148
1149     # Make a copy of the build-root environment to use for this config.
1150     env = main.Clone()
1151     env['BUILDDIR'] = variant_path
1152
1153     # variant_dir is the tail component of build path, and is used to
1154     # determine the build parameters (e.g., 'X86')
1155     (build_root, variant_dir) = splitpath(variant_path)
1156
1157     # Set env variables according to the build directory config.
1158     sticky_vars.files = []
1159     # Variables for $BUILD_ROOT/$VARIANT_DIR are stored in
1160     # $BUILD_ROOT/variables/$VARIANT_DIR so you can nuke
1161     # $BUILD_ROOT/$VARIANT_DIR without losing your variables settings.
1162     current_vars_file = joinpath(build_root, 'variables', variant_dir)
1163     if isfile(current_vars_file):
1164         sticky_vars.files.append(current_vars_file)
1165         if not GetOption('silent'):
1166             print("Using saved variables file %s" % current_vars_file)
1167     elif variant_dir in ext_build_dirs:
1168         # Things in ext are built without a variant directory.
1169         continue
1170     else:
1171         # Build dir-specific variables file doesn't exist.
1172
1173         # Make sure the directory is there so we can create it later
1174         opt_dir = dirname(current_vars_file)
1175         if not isdir(opt_dir):
1176             mkdir(opt_dir)
1177
1178         # Get default build variables from source tree.  Variables are
1179         # normally determined by name of $VARIANT_DIR, but can be
1180         # overridden by '--default=' arg on command line.
1181         default = GetOption('default')
1182         opts_dir = joinpath(main.root.abspath, 'build_opts')
1183         if default:
1184             default_vars_files = [joinpath(build_root, 'variables', default),
1185                                   joinpath(opts_dir, default)]
1186         else:
1187             default_vars_files = [joinpath(opts_dir, variant_dir)]
1188         existing_files = list(filter(isfile, default_vars_files))
1189         if existing_files:
1190             default_vars_file = existing_files[0]
1191             sticky_vars.files.append(default_vars_file)
1192             print("Variables file %s not found,\n  using defaults in %s"
1193                   % (current_vars_file, default_vars_file))
1194         else:
1195             error("Cannot find variables file %s or default file(s) %s"
1196                   % (current_vars_file, ' or '.join(default_vars_files)))
1197             Exit(1)
1198
1199     # Apply current variable settings to env
1200     sticky_vars.Update(env)
1201
1202     help_texts["local_vars"] += \
1203         "Build variables for %s:\n" % variant_dir \
1204                  + sticky_vars.GenerateHelpText(env)
1205
1206     # Process variable settings.
1207
1208     if not have_fenv and env['USE_FENV']:
1209         warning("<fenv.h> not available; forcing USE_FENV to False in",
1210                 variant_dir + ".")
1211         env['USE_FENV'] = False
1212
1213     if not env['USE_FENV']:
1214         warning("No IEEE FP rounding mode control in", variant_dir + ".\n"
1215                 "FP results may deviate slightly from other platforms.")
1216
1217     if not have_png and env['USE_PNG']:
1218         warning("<png.h> not available; forcing USE_PNG to False in",
1219                 variant_dir + ".")
1220         env['USE_PNG'] = False
1221
1222     if env['USE_PNG']:
1223         env.Append(LIBS=['png'])
1224
1225     if env['EFENCE']:
1226         env.Append(LIBS=['efence'])
1227
1228     if env['USE_KVM']:
1229         if not have_kvm:
1230             warning("Can not enable KVM, host seems to lack KVM support")
1231             env['USE_KVM'] = False
1232         elif not is_isa_kvm_compatible(env['TARGET_ISA']):
1233             print("Info: KVM support disabled due to unsupported host and "
1234                   "target ISA combination")
1235             env['USE_KVM'] = False
1236
1237     if env['USE_TUNTAP']:
1238         if not have_tuntap:
1239             warning("Can't connect EtherTap with a tap device.")
1240             env['USE_TUNTAP'] = False
1241
1242     if env['BUILD_GPU']:
1243         env.Append(CPPDEFINES=['BUILD_GPU'])
1244
1245     # Warn about missing optional functionality
1246     if env['USE_KVM']:
1247         if not main['HAVE_PERF_ATTR_EXCLUDE_HOST']:
1248             warning("perf_event headers lack support for the exclude_host "
1249                     "attribute. KVM instruction counts will be inaccurate.")
1250
1251     # Save sticky variable settings back to current variables file
1252     sticky_vars.Save(current_vars_file, env)
1253
1254     if env['USE_SSE2']:
1255         env.Append(CCFLAGS=['-msse2'])
1256
1257     env.Append(CCFLAGS='$CCFLAGS_EXTRA')
1258     env.Append(LINKFLAGS='$LDFLAGS_EXTRA')
1259
1260     # The src/SConscript file sets up the build rules in 'env' according
1261     # to the configured variables.  It returns a list of environments,
1262     # one for each variant build (debug, opt, etc.)
1263     SConscript('src/SConscript', variant_dir = variant_path, exports = 'env')
1264
1265 # base help text
1266 Help('''
1267 Usage: scons [scons options] [build variables] [target(s)]
1268
1269 Extra scons options:
1270 %(options)s
1271
1272 Global build variables:
1273 %(global_vars)s
1274
1275 %(local_vars)s
1276 ''' % help_texts)