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 def find_first_prog(prog_names):
 218     """Find the absolute path to the first existing binary in prog_names"""
 219
 220     if not isinstance(prog_names, (list, tuple)):
 221         prog_names = [ prog_names ]
 222
 223     for p in prog_names:
 224         p = main.WhereIs(p)
 225         if p is not None:
 226             return p
 227
 228     return None
 229
 230 # Each target must have 'build' in the interior of the path; the
 231 # directory below this will determine the build parameters.  For
 232 # example, for target 'foo/bar/build/X86/arch/x86/blah.do' we
 233 # recognize that X86 specifies the configuration because it
 234 # follow 'build' in the build path.
 235
 236 # The funky assignment to "[:]" is needed to replace the list contents
 237 # in place rather than reassign the symbol to a new list, which
 238 # doesn't work (obviously!).
 239 BUILD_TARGETS[:] = makePathListAbsolute(BUILD_TARGETS)
 240
 241 # Generate a list of the unique build roots and configs that the
 242 # collected targets reference.
 243 variant_paths = []
 244 build_root = None
 245 for t in BUILD_TARGETS:
 246     path_dirs = t.split('/')
 247     try:
 248         build_top = rfind(path_dirs, 'build', -2)
 249     except:
 250         error("No non-leaf 'build' dir found on target path.", t)
 251     this_build_root = joinpath('/',*path_dirs[:build_top+1])
 252     if not build_root:
 253         build_root = this_build_root
 254     else:
 255         if this_build_root != build_root:
 256             error("build targets not under same build root\n"
 257                   "  %s\n  %s" % (build_root, this_build_root))
 258     variant_path = joinpath('/',*path_dirs[:build_top+2])
 259     if variant_path not in variant_paths:
 260         variant_paths.append(variant_path)
 261
 262 # Make sure build_root exists (might not if this is the first build there)
 263 if not isdir(build_root):
 264     mkdir(build_root)
 265 main['BUILDROOT'] = build_root
 266
 267 Export('main')
 268
 269 main.SConsignFile(joinpath(build_root, "sconsign"))
 270
 271 # Default duplicate option is to use hard links, but this messes up
 272 # when you use emacs to edit a file in the target dir, as emacs moves
 273 # file to file~ then copies to file, breaking the link.  Symbolic
 274 # (soft) links work better.
 275 main.SetOption('duplicate', 'soft-copy')
 276
 277 #
 278 # Set up global sticky variables... these are common to an entire build
 279 # tree (not specific to a particular build like X86)
 280 #
 281
 282 global_vars_file = joinpath(build_root, 'variables.global')
 283
 284 global_vars = Variables(global_vars_file, args=ARGUMENTS)
 285
 286 global_vars.AddVariables(
 287     ('CC', 'C compiler', environ.get('CC', main['CC'])),
 288     ('CXX', 'C++ compiler', environ.get('CXX', main['CXX'])),
 289     ('CCFLAGS_EXTRA', 'Extra C and C++ compiler flags', ''),
 290     ('LDFLAGS_EXTRA', 'Extra linker flags', ''),
 291     ('PYTHON_CONFIG', 'Python config binary to use',
 292      [ 'python2.7-config', 'python-config' ]),
 293     ('PROTOC', 'protoc tool', environ.get('PROTOC', 'protoc')),
 294     ('BATCH', 'Use batch pool for build and tests', False),
 295     ('BATCH_CMD', 'Batch pool submission command name', 'qdo'),
 296     ('M5_BUILD_CACHE', 'Cache built objects in this directory', False),
 297     ('EXTRAS', 'Add extra directories to the compilation', '')
 298     )
 299
 300 # Update main environment with values from ARGUMENTS & global_vars_file
 301 global_vars.Update(main)
 302 help_texts["global_vars"] += global_vars.GenerateHelpText(main)
 303
 304 # Save sticky variable settings back to current variables file
 305 global_vars.Save(global_vars_file, main)
 306
 307 # Parse EXTRAS variable to build list of all directories where we're
 308 # look for sources etc.  This list is exported as extras_dir_list.
 309 base_dir = main.srcdir.abspath
 310 if main['EXTRAS']:
 311     extras_dir_list = makePathListAbsolute(main['EXTRAS'].split(':'))
 312 else:
 313     extras_dir_list = []
 314
 315 Export('base_dir')
 316 Export('extras_dir_list')
 317
 318 # the ext directory should be on the #includes path
 319 main.Append(CPPPATH=[Dir('ext')])
 320
 321 # Add shared top-level headers
 322 main.Prepend(CPPPATH=Dir('include'))
 323
 324 if GetOption('verbose'):
 325     def MakeAction(action, string, *args, **kwargs):
 326         return Action(action, *args, **kwargs)
 327 else:
 328     MakeAction = Action
 329     main['CCCOMSTR']        = Transform("CC")
 330     main['CXXCOMSTR']       = Transform("CXX")
 331     main['ASCOMSTR']        = Transform("AS")
 332     main['ARCOMSTR']        = Transform("AR", 0)
 333     main['LINKCOMSTR']      = Transform("LINK", 0)
 334     main['SHLINKCOMSTR']    = Transform("SHLINK", 0)
 335     main['RANLIBCOMSTR']    = Transform("RANLIB", 0)
 336     main['M4COMSTR']        = Transform("M4")
 337     main['SHCCCOMSTR']      = Transform("SHCC")
 338     main['SHCXXCOMSTR']     = Transform("SHCXX")
 339 Export('MakeAction')
 340
 341 # Initialize the Link-Time Optimization (LTO) flags
 342 main['LTO_CCFLAGS'] = []
 343 main['LTO_LDFLAGS'] = []
 344
 345 # According to the readme, tcmalloc works best if the compiler doesn't
 346 # assume that we're using the builtin malloc and friends. These flags
 347 # are compiler-specific, so we need to set them after we detect which
 348 # compiler we're using.
 349 main['TCMALLOC_CCFLAGS'] = []
 350
 351 CXX_version = readCommand([main['CXX'],'--version'], exception=False)
 352 CXX_V = readCommand([main['CXX'],'-V'], exception=False)
 353
 354 main['GCC'] = CXX_version and CXX_version.find('g++') >= 0
 355 main['CLANG'] = CXX_version and CXX_version.find('clang') >= 0
 356 if main['GCC'] + main['CLANG'] > 1:
 357     error('Two compilers enabled at once?')
 358
 359 # Set up default C++ compiler flags
 360 if main['GCC'] or main['CLANG']:
 361     # As gcc and clang share many flags, do the common parts here
 362     main.Append(CCFLAGS=['-pipe'])
 363     main.Append(CCFLAGS=['-fno-strict-aliasing'])
 364     # Enable -Wall and -Wextra and then disable the few warnings that
 365     # we consistently violate
 366     main.Append(CCFLAGS=['-Wall', '-Wundef', '-Wextra',
 367                          '-Wno-sign-compare', '-Wno-unused-parameter'])
 368     # We always compile using C++11
 369     main.Append(CXXFLAGS=['-std=c++11'])
 370     if sys.platform.startswith('freebsd'):
 371         main.Append(CCFLAGS=['-I/usr/local/include'])
 372         main.Append(CXXFLAGS=['-I/usr/local/include'])
 373
 374     main.Append(LINKFLAGS='-Wl,--as-needed')
 375     main['FILTER_PSHLINKFLAGS'] = lambda x: str(x).replace(' -shared', '')
 376     main['PSHLINKFLAGS'] = main.subst('${FILTER_PSHLINKFLAGS(SHLINKFLAGS)}')
 377     if GetOption('gold_linker'):
 378         main.Append(LINKFLAGS='-fuse-ld=gold')
 379     main['PLINKFLAGS'] = main.get('LINKFLAGS')
 380     shared_partial_flags = ['-r', '-nostdlib']
 381     main.Append(PSHLINKFLAGS=shared_partial_flags)
 382     main.Append(PLINKFLAGS=shared_partial_flags)
 383
 384     # Treat warnings as errors but white list some warnings that we
 385     # want to allow (e.g., deprecation warnings).
 386     main.Append(CCFLAGS=['-Werror',
 387                          '-Wno-error=deprecated-declarations',
 388                          '-Wno-error=deprecated',
 389                         ])
 390 else:
 391     error('\n'.join((
 392           "Don't know what compiler options to use for your compiler.",
 393           "compiler: " + main['CXX'],
 394           "version: " + CXX_version.replace('\n', '<nl>') if
 395                 CXX_version else 'COMMAND NOT FOUND!',
 396           "If you're trying to use a compiler other than GCC",
 397           "or clang, there appears to be something wrong with your",
 398           "environment.",
 399           "",
 400           "If you are trying to use a compiler other than those listed",
 401           "above you will need to ease fix SConstruct and ",
 402           "src/SConscript to support that compiler.")))
 403
 404 if main['GCC']:
 405     # Check for a supported version of gcc. >= 4.8 is chosen for its
 406     # level of c++11 support. See
 407     # http://gcc.gnu.org/projects/cxx0x.html for details.
 408     gcc_version = readCommand([main['CXX'], '-dumpversion'], exception=False)
 409     if compareVersions(gcc_version, "4.8") < 0:
 410         error('gcc version 4.8 or newer required.\n'
 411               'Installed version:', gcc_version)
 412         Exit(1)
 413
 414     main['GCC_VERSION'] = gcc_version
 415
 416     if compareVersions(gcc_version, '4.9') >= 0:
 417         # Incremental linking with LTO is currently broken in gcc versions
 418         # 4.9 and above. A version where everything works completely hasn't
 419         # yet been identified.
 420         #
 421         # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67548
 422         main['BROKEN_INCREMENTAL_LTO'] = True
 423     if compareVersions(gcc_version, '6.0') >= 0:
 424         # gcc versions 6.0 and greater accept an -flinker-output flag which
 425         # selects what type of output the linker should generate. This is
 426         # necessary for incremental lto to work, but is also broken in
 427         # current versions of gcc. It may not be necessary in future
 428         # versions. We add it here since it might be, and as a reminder that
 429         # it exists. It's excluded if lto is being forced.
 430         #
 431         # https://gcc.gnu.org/gcc-6/changes.html
 432         # https://gcc.gnu.org/ml/gcc-patches/2015-11/msg03161.html
 433         # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69866
 434         if not GetOption('force_lto'):
 435             main.Append(PSHLINKFLAGS='-flinker-output=rel')
 436             main.Append(PLINKFLAGS='-flinker-output=rel')
 437
 438     disable_lto = GetOption('no_lto')
 439     if not disable_lto and main.get('BROKEN_INCREMENTAL_LTO', False) and \
 440             not GetOption('force_lto'):
 441         warning('Warning: Your compiler doesn\'t support incremental linking '
 442                 'and lto at the same time, so lto is being disabled. To force '
 443                 'lto on anyway, use the --force-lto option. That will disable '
 444                 'partial linking.')
 445         disable_lto = True
 446
 447     # Add the appropriate Link-Time Optimization (LTO) flags
 448     # unless LTO is explicitly turned off. Note that these flags
 449     # are only used by the fast target.
 450     if not disable_lto:
 451         # Pass the LTO flag when compiling to produce GIMPLE
 452         # output, we merely create the flags here and only append
 453         # them later
 454         main['LTO_CCFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
 455
 456         # Use the same amount of jobs for LTO as we are running
 457         # scons with
 458         main['LTO_LDFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
 459
 460     main.Append(TCMALLOC_CCFLAGS=['-fno-builtin-malloc', '-fno-builtin-calloc',
 461                                   '-fno-builtin-realloc', '-fno-builtin-free'])
 462
 463 elif main['CLANG']:
 464     # Check for a supported version of clang, >= 3.1 is needed to
 465     # support similar features as gcc 4.8. See
 466     # http://clang.llvm.org/cxx_status.html for details
 467     clang_version_re = re.compile(".* version (\d+\.\d+)")
 468     clang_version_match = clang_version_re.search(CXX_version)
 469     if (clang_version_match):
 470         clang_version = clang_version_match.groups()[0]
 471         if compareVersions(clang_version, "3.1") < 0:
 472             error('clang version 3.1 or newer required.\n'
 473                   'Installed version:', clang_version)
 474     else:
 475         error('Unable to determine clang version.')
 476
 477     # clang has a few additional warnings that we disable, extraneous
 478     # parantheses are allowed due to Ruby's printing of the AST,
 479     # finally self assignments are allowed as the generated CPU code
 480     # is relying on this
 481     main.Append(CCFLAGS=['-Wno-parentheses',
 482                          '-Wno-self-assign',
 483                          # Some versions of libstdc++ (4.8?) seem to
 484                          # use struct hash and class hash
 485                          # interchangeably.
 486                          '-Wno-mismatched-tags',
 487                          ])
 488
 489     main.Append(TCMALLOC_CCFLAGS=['-fno-builtin'])
 490
 491     # On Mac OS X/Darwin we need to also use libc++ (part of XCode) as
 492     # opposed to libstdc++, as the later is dated.
 493     if sys.platform == "darwin":
 494         main.Append(CXXFLAGS=['-stdlib=libc++'])
 495         main.Append(LIBS=['c++'])
 496
 497     # On FreeBSD we need libthr.
 498     if sys.platform.startswith('freebsd'):
 499         main.Append(LIBS=['thr'])
 500
 501 # Add sanitizers flags
 502 sanitizers=[]
 503 if GetOption('with_ubsan'):
 504     # Only gcc >= 4.9 supports UBSan, so check both the version
 505     # and the command-line option before adding the compiler and
 506     # linker flags.
 507     if not main['GCC'] or compareVersions(main['GCC_VERSION'], '4.9') >= 0:
 508         sanitizers.append('undefined')
 509 if GetOption('with_asan'):
 510     # Available for gcc >= 4.8 or llvm >= 3.1 both a requirement
 511     # by the build system
 512     sanitizers.append('address')
 513 if sanitizers:
 514     sanitizers = ','.join(sanitizers)
 515     if main['GCC'] or main['CLANG']:
 516         main.Append(CCFLAGS=['-fsanitize=%s' % sanitizers,
 517                              '-fno-omit-frame-pointer'],
 518                     LINKFLAGS='-fsanitize=%s' % sanitizers)
 519     else:
 520         warning("Don't know how to enable %s sanitizer(s) for your "
 521                 "compiler." % sanitizers)
 522
 523 # Set up common yacc/bison flags (needed for Ruby)
 524 main['YACCFLAGS'] = '-d'
 525 main['YACCHXXFILESUFFIX'] = '.hh'
 526
 527 # Do this after we save setting back, or else we'll tack on an
 528 # extra 'qdo' every time we run scons.
 529 if main['BATCH']:
 530     main['CC']     = main['BATCH_CMD'] + ' ' + main['CC']
 531     main['CXX']    = main['BATCH_CMD'] + ' ' + main['CXX']
 532     main['AS']     = main['BATCH_CMD'] + ' ' + main['AS']
 533     main['AR']     = main['BATCH_CMD'] + ' ' + main['AR']
 534     main['RANLIB'] = main['BATCH_CMD'] + ' ' + main['RANLIB']
 535
 536 if sys.platform == 'cygwin':
 537     # cygwin has some header file issues...
 538     main.Append(CCFLAGS=["-Wno-uninitialized"])
 539
 540
 541 have_pkg_config = readCommand(['pkg-config', '--version'], exception='')
 542
 543 # Check for the protobuf compiler
 544 try:
 545     main['HAVE_PROTOC'] = True
 546     protoc_version = readCommand([main['PROTOC'], '--version']).split()
 547
 548     # First two words should be "libprotoc x.y.z"
 549     if len(protoc_version) < 2 or protoc_version[0] != 'libprotoc':
 550         warning('Protocol buffer compiler (protoc) not found.\n'
 551                 'Please install protobuf-compiler for tracing support.')
 552         main['HAVE_PROTOC'] = False
 553     else:
 554         # Based on the availability of the compress stream wrappers,
 555         # require 2.1.0
 556         min_protoc_version = '2.1.0'
 557         if compareVersions(protoc_version[1], min_protoc_version) < 0:
 558             warning('protoc version', min_protoc_version,
 559                     'or newer required.\n'
 560                     'Installed version:', protoc_version[1])
 561             main['HAVE_PROTOC'] = False
 562         else:
 563             # Attempt to determine the appropriate include path and
 564             # library path using pkg-config, that means we also need to
 565             # check for pkg-config. Note that it is possible to use
 566             # protobuf without the involvement of pkg-config. Later on we
 567             # check go a library config check and at that point the test
 568             # will fail if libprotobuf cannot be found.
 569             if have_pkg_config:
 570                 try:
 571                     # Attempt to establish what linking flags to add for
 572                     # protobuf
 573                     # using pkg-config
 574                     main.ParseConfig(
 575                             'pkg-config --cflags --libs-only-L protobuf')
 576                 except:
 577                     warning('pkg-config could not get protobuf flags.')
 578 except Exception as e:
 579     warning('While checking protoc version:', str(e))
 580     main['HAVE_PROTOC'] = False
 581
 582 # Check for 'timeout' from GNU coreutils. If present, regressions will
 583 # be run with a time limit. We require version 8.13 since we rely on
 584 # support for the '--foreground' option.
 585 if sys.platform.startswith('freebsd'):
 586     timeout_lines = readCommand(['gtimeout', '--version'],
 587                                 exception='').splitlines()
 588 else:
 589     timeout_lines = readCommand(['timeout', '--version'],
 590                                 exception='').splitlines()
 591 # Get the first line and tokenize it
 592 timeout_version = timeout_lines[0].split() if timeout_lines else []
 593 main['TIMEOUT'] =  timeout_version and \
 594     compareVersions(timeout_version[-1], '8.13') >= 0
 595
 596 # Add a custom Check function to test for structure members.
 597 def CheckMember(context, include, decl, member, include_quotes="<>"):
 598     context.Message("Checking for member %s in %s..." %
 599                     (member, decl))
 600     text = """
 601 #include %(header)s
 602 int main(){
 603   %(decl)s test;
 604   (void)test.%(member)s;
 605   return 0;
 606 };
 607 """ % { "header" : include_quotes[0] + include + include_quotes[1],
 608         "decl" : decl,
 609         "member" : member,
 610         }
 611
 612     ret = context.TryCompile(text, extension=".cc")
 613     context.Result(ret)
 614     return ret
 615
 616 # Platform-specific configuration.  Note again that we assume that all
 617 # builds under a given build root run on the same host platform.
 618 conf = Configure(main,
 619                  conf_dir = joinpath(build_root, '.scons_config'),
 620                  log_file = joinpath(build_root, 'scons_config.log'),
 621                  custom_tests = {
 622         'CheckMember' : CheckMember,
 623         })
 624
 625 # Check if we should compile a 64 bit binary on Mac OS X/Darwin
 626 try:
 627     import platform
 628     uname = platform.uname()
 629     if uname[0] == 'Darwin' and compareVersions(uname[2], '9.0.0') >= 0:
 630         if int(readCommand('sysctl -n hw.cpu64bit_capable')[0]):
 631             main.Append(CCFLAGS=['-arch', 'x86_64'])
 632             main.Append(CFLAGS=['-arch', 'x86_64'])
 633             main.Append(LINKFLAGS=['-arch', 'x86_64'])
 634             main.Append(ASFLAGS=['-arch', 'x86_64'])
 635 except:
 636     pass
 637
 638 # Recent versions of scons substitute a "Null" object for Configure()
 639 # when configuration isn't necessary, e.g., if the "--help" option is
 640 # present.  Unfortuantely this Null object always returns false,
 641 # breaking all our configuration checks.  We replace it with our own
 642 # more optimistic null object that returns True instead.
 643 if not conf:
 644     def NullCheck(*args, **kwargs):
 645         return True
 646
 647     class NullConf:
 648         def __init__(self, env):
 649             self.env = env
 650         def Finish(self):
 651             return self.env
 652         def __getattr__(self, mname):
 653             return NullCheck
 654
 655     conf = NullConf(main)
 656
 657 # Cache build files in the supplied directory.
 658 if main['M5_BUILD_CACHE']:
 659     print('Using build cache located at', main['M5_BUILD_CACHE'])
 660     CacheDir(main['M5_BUILD_CACHE'])
 661
 662 main['USE_PYTHON'] = not GetOption('without_python')
 663 if main['USE_PYTHON']:
 664     # Find Python include and library directories for embedding the
 665     # interpreter. We rely on python-config to resolve the appropriate
 666     # includes and linker flags. ParseConfig does not seem to understand
 667     # the more exotic linker flags such as -Xlinker and -export-dynamic so
 668     # we add them explicitly below. If you want to link in an alternate
 669     # version of python, see above for instructions on how to invoke
 670     # scons with the appropriate PATH set.
 671
 672     python_config = find_first_prog(main['PYTHON_CONFIG'])
 673     if python_config is None:
 674         error("Can't find a suitable python-config, tried %s" % \
 675               main['PYTHON_CONFIG'])
 676
 677     print("Info: Using Python config: %s" % (python_config, ))
 678     py_includes = readCommand([python_config, '--includes'],
 679                               exception='').split()
 680     py_includes = filter(lambda s: match(r'.*\/include\/.*',s), py_includes)
 681     # Strip the -I from the include folders before adding them to the
 682     # CPPPATH
 683     py_includes = map(lambda s: s[2:] if s.startswith('-I') else s, py_includes)
 684     main.Append(CPPPATH=py_includes)
 685
 686     # Read the linker flags and split them into libraries and other link
 687     # flags. The libraries are added later through the call the CheckLib.
 688     py_ld_flags = readCommand([python_config, '--ldflags'],
 689         exception='').split()
 690     py_libs = []
 691     for lib in py_ld_flags:
 692          if not lib.startswith('-l'):
 693              main.Append(LINKFLAGS=[lib])
 694          else:
 695              lib = lib[2:]
 696              if lib not in py_libs:
 697                  py_libs.append(lib)
 698
 699     # verify that this stuff works
 700     if not conf.CheckHeader('Python.h', '<>'):
 701         error("Check failed for Python.h header in",
 702                 ' '.join(py_includes), "\n"
 703               "Two possible reasons:\n"
 704               "1. Python headers are not installed (You can install the "
 705               "package python-dev on Ubuntu and RedHat)\n"
 706               "2. SCons is using a wrong C compiler. This can happen if "
 707               "CC has the wrong value.\n"
 708               "CC = %s" % main['CC'])
 709
 710     for lib in py_libs:
 711         if not conf.CheckLib(lib):
 712             error("Can't find library %s required by python." % lib)
 713
 714 # On Solaris you need to use libsocket for socket ops
 715 if not conf.CheckLibWithHeader(None, 'sys/socket.h', 'C++', 'accept(0,0,0);'):
 716    if not conf.CheckLibWithHeader('socket', 'sys/socket.h',
 717                                   'C++', 'accept(0,0,0);'):
 718        error("Can't find library with socket calls (e.g. accept()).")
 719
 720 # Check for zlib.  If the check passes, libz will be automatically
 721 # added to the LIBS environment variable.
 722 if not conf.CheckLibWithHeader('z', 'zlib.h', 'C++','zlibVersion();'):
 723     error('Did not find needed zlib compression library '
 724           'and/or zlib.h header file.\n'
 725           'Please install zlib and try again.')
 726
 727 # If we have the protobuf compiler, also make sure we have the
 728 # development libraries. If the check passes, libprotobuf will be
 729 # automatically added to the LIBS environment variable. After
 730 # this, we can use the HAVE_PROTOBUF flag to determine if we have
 731 # got both protoc and libprotobuf available.
 732 main['HAVE_PROTOBUF'] = main['HAVE_PROTOC'] and \
 733     conf.CheckLibWithHeader('protobuf', 'google/protobuf/message.h',
 734                             'C++', 'GOOGLE_PROTOBUF_VERIFY_VERSION;')
 735
 736 # Valgrind gets much less confused if you tell it when you're using
 737 # alternative stacks.
 738 main['HAVE_VALGRIND'] = conf.CheckCHeader('valgrind/valgrind.h')
 739
 740 # If we have the compiler but not the library, print another warning.
 741 if main['HAVE_PROTOC'] and not main['HAVE_PROTOBUF']:
 742     warning('Did not find protocol buffer library and/or headers.\n'
 743             'Please install libprotobuf-dev for tracing support.')
 744
 745 # Check for librt.
 746 have_posix_clock = \
 747     conf.CheckLibWithHeader(None, 'time.h', 'C',
 748                             'clock_nanosleep(0,0,NULL,NULL);') or \
 749     conf.CheckLibWithHeader('rt', 'time.h', 'C',
 750                             'clock_nanosleep(0,0,NULL,NULL);')
 751
 752 have_posix_timers = \
 753     conf.CheckLibWithHeader([None, 'rt'], [ 'time.h', 'signal.h' ], 'C',
 754                             'timer_create(CLOCK_MONOTONIC, NULL, NULL);')
 755
 756 if not GetOption('without_tcmalloc'):
 757     if conf.CheckLib('tcmalloc'):
 758         main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
 759     elif conf.CheckLib('tcmalloc_minimal'):
 760         main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
 761     else:
 762         warning("You can get a 12% performance improvement by "
 763                 "installing tcmalloc (libgoogle-perftools-dev package "
 764                 "on Ubuntu or RedHat).")
 765
 766
 767 # Detect back trace implementations. The last implementation in the
 768 # list will be used by default.
 769 backtrace_impls = [ "none" ]
 770
 771 backtrace_checker = 'char temp;' + \
 772     ' backtrace_symbols_fd((void*)&temp, 0, 0);'
 773 if conf.CheckLibWithHeader(None, 'execinfo.h', 'C', backtrace_checker):
 774     backtrace_impls.append("glibc")
 775 elif conf.CheckLibWithHeader('execinfo', 'execinfo.h', 'C',
 776                              backtrace_checker):
 777     # NetBSD and FreeBSD need libexecinfo.
 778     backtrace_impls.append("glibc")
 779     main.Append(LIBS=['execinfo'])
 780
 781 if backtrace_impls[-1] == "none":
 782     default_backtrace_impl = "none"
 783     warning("No suitable back trace implementation found.")
 784
 785 if not have_posix_clock:
 786     warning("Can't find library for POSIX clocks.")
 787
 788 # Check for <fenv.h> (C99 FP environment control)
 789 have_fenv = conf.CheckHeader('fenv.h', '<>')
 790 if not have_fenv:
 791     warning("Header file <fenv.h> not found.\n"
 792             "This host has no IEEE FP rounding mode control.")
 793
 794 # Check for <png.h> (libpng library needed if wanting to dump
 795 # frame buffer image in png format)
 796 have_png = conf.CheckHeader('png.h', '<>')
 797 if not have_png:
 798     warning("Header file <png.h> not found.\n"
 799             "This host has no libpng library.\n"
 800             "Disabling support for PNG framebuffers.")
 801
 802 # Check if we should enable KVM-based hardware virtualization. The API
 803 # we rely on exists since version 2.6.36 of the kernel, but somehow
 804 # the KVM_API_VERSION does not reflect the change. We test for one of
 805 # the types as a fall back.
 806 have_kvm = conf.CheckHeader('linux/kvm.h', '<>')
 807 if not have_kvm:
 808     print("Info: Compatible header file <linux/kvm.h> not found, "
 809           "disabling KVM support.")
 810
 811 # Check if the TUN/TAP driver is available.
 812 have_tuntap = conf.CheckHeader('linux/if_tun.h', '<>')
 813 if not have_tuntap:
 814     print("Info: Compatible header file <linux/if_tun.h> not found.")
 815
 816 # x86 needs support for xsave. We test for the structure here since we
 817 # won't be able to run new tests by the time we know which ISA we're
 818 # targeting.
 819 have_kvm_xsave = conf.CheckTypeSize('struct kvm_xsave',
 820                                     '#include <linux/kvm.h>') != 0
 821
 822 # Check if the requested target ISA is compatible with the host
 823 def is_isa_kvm_compatible(isa):
 824     try:
 825         import platform
 826         host_isa = platform.machine()
 827     except:
 828         warning("Failed to determine host ISA.")
 829         return False
 830
 831     if not have_posix_timers:
 832         warning("Can not enable KVM, host seems to lack support "
 833                 "for POSIX timers")
 834         return False
 835
 836     if isa == "arm":
 837         return host_isa in ( "armv7l", "aarch64" )
 838     elif isa == "x86":
 839         if host_isa != "x86_64":
 840             return False
 841
 842         if not have_kvm_xsave:
 843             warning("KVM on x86 requires xsave support in kernel headers.")
 844             return False
 845
 846         return True
 847     else:
 848         return False
 849
 850
 851 # Check if the exclude_host attribute is available. We want this to
 852 # get accurate instruction counts in KVM.
 853 main['HAVE_PERF_ATTR_EXCLUDE_HOST'] = conf.CheckMember(
 854     'linux/perf_event.h', 'struct perf_event_attr', 'exclude_host')
 855
 856 def check_hdf5():
 857     return \
 858         conf.CheckLibWithHeader('hdf5', 'hdf5.h', 'C',
 859                                 'H5Fcreate("", 0, 0, 0);') and \
 860         conf.CheckLibWithHeader('hdf5_cpp', 'H5Cpp.h', 'C++',
 861                                 'H5::H5File("", 0);')
 862
 863 def check_hdf5_pkg(name):
 864     print("Checking for %s using pkg-config..." % name, end="")
 865     if not have_pkg_config:
 866         print(" pkg-config not found")
 867         return False
 868
 869     try:
 870         main.ParseConfig('pkg-config --cflags-only-I --libs-only-L %s' % name)
 871         print(" yes")
 872         return True
 873     except:
 874         print(" no")
 875         return False
 876
 877 # Check if there is a pkg-config configuration for hdf5. If we find
 878 # it, setup the environment to enable linking and header inclusion. We
 879 # don't actually try to include any headers or link with hdf5 at this
 880 # stage.
 881 if not check_hdf5_pkg('hdf5-serial'):
 882     check_hdf5_pkg('hdf5')
 883
 884 # Check if the HDF5 libraries can be found. This check respects the
 885 # include path and library path provided by pkg-config. We perform
 886 # this check even if there isn't a pkg-config configuration for hdf5
 887 # since some installations don't use pkg-config.
 888 have_hdf5 = check_hdf5()
 889 if not have_hdf5:
 890     print("Warning: Couldn't find any HDF5 C++ libraries. Disabling")
 891     print("         HDF5 support.")
 892
 893 ######################################################################
 894 #
 895 # Finish the configuration
 896 #
 897 main = conf.Finish()
 898
 899 ######################################################################
 900 #
 901 # Collect all non-global variables
 902 #
 903
 904 # Define the universe of supported ISAs
 905 all_isa_list = [ ]
 906 all_gpu_isa_list = [ ]
 907 Export('all_isa_list')
 908 Export('all_gpu_isa_list')
 909
 910 class CpuModel(object):
 911     '''The CpuModel class encapsulates everything the ISA parser needs to
 912     know about a particular CPU model.'''
 913
 914     # Dict of available CPU model objects.  Accessible as CpuModel.dict.
 915     dict = {}
 916
 917     # Constructor.  Automatically adds models to CpuModel.dict.
 918     def __init__(self, name, default=False):
 919         self.name = name           # name of model
 920
 921         # This cpu is enabled by default
 922         self.default = default
 923
 924         # Add self to dict
 925         if name in CpuModel.dict:
 926             raise AttributeError("CpuModel '%s' already registered" % name)
 927         CpuModel.dict[name] = self
 928
 929 Export('CpuModel')
 930
 931 # Sticky variables get saved in the variables file so they persist from
 932 # one invocation to the next (unless overridden, in which case the new
 933 # value becomes sticky).
 934 sticky_vars = Variables(args=ARGUMENTS)
 935 Export('sticky_vars')
 936
 937 # Sticky variables that should be exported
 938 export_vars = []
 939 Export('export_vars')
 940
 941 # For Ruby
 942 all_protocols = []
 943 Export('all_protocols')
 944 protocol_dirs = []
 945 Export('protocol_dirs')
 946 slicc_includes = []
 947 Export('slicc_includes')
 948
 949 # Walk the tree and execute all SConsopts scripts that wil add to the
 950 # above variables
 951 if GetOption('verbose'):
 952     print("Reading SConsopts")
 953 for bdir in [ base_dir ] + extras_dir_list:
 954     if not isdir(bdir):
 955         error("Directory '%s' does not exist." % bdir)
 956     for root, dirs, files in os.walk(bdir):
 957         if 'SConsopts' in files:
 958             if GetOption('verbose'):
 959                 print("Reading", joinpath(root, 'SConsopts'))
 960             SConscript(joinpath(root, 'SConsopts'))
 961
 962 all_isa_list.sort()
 963 all_gpu_isa_list.sort()
 964
 965 sticky_vars.AddVariables(
 966     EnumVariable('TARGET_ISA', 'Target ISA', 'alpha', all_isa_list),
 967     EnumVariable('TARGET_GPU_ISA', 'Target GPU ISA', 'hsail', all_gpu_isa_list),
 968     ListVariable('CPU_MODELS', 'CPU models',
 969                  sorted(n for n,m in CpuModel.dict.iteritems() if m.default),
 970                  sorted(CpuModel.dict.keys())),
 971     BoolVariable('EFENCE', 'Link with Electric Fence malloc debugger',
 972                  False),
 973     BoolVariable('USE_SSE2',
 974                  'Compile for SSE2 (-msse2) to get IEEE FP on x86 hosts',
 975                  False),
 976     BoolVariable('USE_POSIX_CLOCK', 'Use POSIX Clocks', have_posix_clock),
 977     BoolVariable('USE_FENV', 'Use <fenv.h> IEEE mode control', have_fenv),
 978     BoolVariable('USE_PNG',  'Enable support for PNG images', have_png),
 979     BoolVariable('CP_ANNOTATE', 'Enable critical path annotation capability',
 980                  False),
 981     BoolVariable('USE_KVM', 'Enable hardware virtualized (KVM) CPU models',
 982                  have_kvm),
 983     BoolVariable('USE_TUNTAP',
 984                  'Enable using a tap device to bridge to the host network',
 985                  have_tuntap),
 986     BoolVariable('BUILD_GPU', 'Build the compute-GPU model', False),
 987     EnumVariable('PROTOCOL', 'Coherence protocol for Ruby', 'None',
 988                   all_protocols),
 989     EnumVariable('BACKTRACE_IMPL', 'Post-mortem dump implementation',
 990                  backtrace_impls[-1], backtrace_impls),
 991     ('NUMBER_BITS_PER_SET', 'Max elements in set (default 64)',
 992                  64),
 993     BoolVariable('USE_HDF5', 'Enable the HDF5 support', have_hdf5),
 994     )
 995
 996 # These variables get exported to #defines in config/*.hh (see src/SConscript).
 997 export_vars += ['USE_FENV', 'TARGET_ISA', 'TARGET_GPU_ISA', 'CP_ANNOTATE',
 998                 'USE_POSIX_CLOCK', 'USE_KVM', 'USE_TUNTAP', 'PROTOCOL',
 999                 'HAVE_PROTOBUF', 'HAVE_VALGRIND',
1000                 'HAVE_PERF_ATTR_EXCLUDE_HOST', 'USE_PNG',
1001                 'NUMBER_BITS_PER_SET', 'USE_HDF5']
1002
1003 ###################################################
1004 #
1005 # Define a SCons builder for configuration flag headers.
1006 #
1007 ###################################################
1008
1009 # This function generates a config header file that #defines the
1010 # variable symbol to the current variable setting (0 or 1).  The source
1011 # operands are the name of the variable and a Value node containing the
1012 # value of the variable.
1013 def build_config_file(target, source, env):
1014     (variable, value) = [s.get_contents() for s in source]
1015     f = file(str(target[0]), 'w')
1016     print('#define', variable, value, file=f)
1017     f.close()
1018     return None
1019
1020 # Combine the two functions into a scons Action object.
1021 config_action = MakeAction(build_config_file, Transform("CONFIG H", 2))
1022
1023 # The emitter munges the source & target node lists to reflect what
1024 # we're really doing.
1025 def config_emitter(target, source, env):
1026     # extract variable name from Builder arg
1027     variable = str(target[0])
1028     # True target is config header file
1029     target = joinpath('config', variable.lower() + '.hh')
1030     val = env[variable]
1031     if isinstance(val, bool):
1032         # Force value to 0/1
1033         val = int(val)
1034     elif isinstance(val, str):
1035         val = '"' + val + '"'
1036
1037     # Sources are variable name & value (packaged in SCons Value nodes)
1038     return ([target], [Value(variable), Value(val)])
1039
1040 config_builder = Builder(emitter = config_emitter, action = config_action)
1041
1042 main.Append(BUILDERS = { 'ConfigFile' : config_builder })
1043
1044 ###################################################
1045 #
1046 # Builders for static and shared partially linked object files.
1047 #
1048 ###################################################
1049
1050 partial_static_builder = Builder(action=SCons.Defaults.LinkAction,
1051                                  src_suffix='$OBJSUFFIX',
1052                                  src_builder=['StaticObject', 'Object'],
1053                                  LINKFLAGS='$PLINKFLAGS',
1054                                  LIBS='')
1055
1056 def partial_shared_emitter(target, source, env):
1057     for tgt in target:
1058         tgt.attributes.shared = 1
1059     return (target, source)
1060 partial_shared_builder = Builder(action=SCons.Defaults.ShLinkAction,
1061                                  emitter=partial_shared_emitter,
1062                                  src_suffix='$SHOBJSUFFIX',
1063                                  src_builder='SharedObject',
1064                                  SHLINKFLAGS='$PSHLINKFLAGS',
1065                                  LIBS='')
1066
1067 main.Append(BUILDERS = { 'PartialShared' : partial_shared_builder,
1068                          'PartialStatic' : partial_static_builder })
1069
1070 def add_local_rpath(env, *targets):
1071     '''Set up an RPATH for a library which lives in the build directory.
1072
1073     The construction environment variable BIN_RPATH_PREFIX should be set to
1074     the relative path of the build directory starting from the location of the
1075     binary.'''
1076     for target in targets:
1077         target = env.Entry(target)
1078         if not isinstance(target, SCons.Node.FS.Dir):
1079             target = target.dir
1080         relpath = os.path.relpath(target.abspath, env['BUILDDIR'])
1081         components = [
1082             '\\$$ORIGIN',
1083             '${BIN_RPATH_PREFIX}',
1084             relpath
1085         ]
1086         env.Append(RPATH=[env.Literal(os.path.join(*components))])
1087
1088 if sys.platform != "darwin":
1089     main.Append(LINKFLAGS=Split('-z origin'))
1090
1091 main.AddMethod(add_local_rpath, 'AddLocalRPATH')
1092
1093 # builds in ext are shared across all configs in the build root.
1094 ext_dir = abspath(joinpath(str(main.root), 'ext'))
1095 ext_build_dirs = []
1096 for root, dirs, files in os.walk(ext_dir):
1097     if 'SConscript' in files:
1098         build_dir = os.path.relpath(root, ext_dir)
1099         ext_build_dirs.append(build_dir)
1100         main.SConscript(joinpath(root, 'SConscript'),
1101                         variant_dir=joinpath(build_root, build_dir))
1102
1103 gdb_xml_dir = joinpath(ext_dir, 'gdb-xml')
1104 Export('gdb_xml_dir')
1105
1106 main.Prepend(CPPPATH=Dir('ext/pybind11/include/'))
1107
1108 ###################################################
1109 #
1110 # This builder and wrapper method are used to set up a directory with
1111 # switching headers. Those are headers which are in a generic location and
1112 # that include more specific headers from a directory chosen at build time
1113 # based on the current build settings.
1114 #
1115 ###################################################
1116
1117 def build_switching_header(target, source, env):
1118     path = str(target[0])
1119     subdir = str(source[0])
1120     dp, fp = os.path.split(path)
1121     dp = os.path.relpath(os.path.realpath(dp),
1122                          os.path.realpath(env['BUILDDIR']))
1123     with open(path, 'w') as hdr:
1124         print('#include "%s/%s/%s"' % (dp, subdir, fp), file=hdr)
1125
1126 switching_header_action = MakeAction(build_switching_header,
1127                                      Transform('GENERATE'))
1128
1129 switching_header_builder = Builder(action=switching_header_action,
1130                                    source_factory=Value,
1131                                    single_source=True)
1132
1133 main.Append(BUILDERS = { 'SwitchingHeader': switching_header_builder })
1134
1135 def switching_headers(self, headers, source):
1136     for header in headers:
1137         self.SwitchingHeader(header, source)
1138
1139 main.AddMethod(switching_headers, 'SwitchingHeaders')
1140
1141 ###################################################
1142 #
1143 # Define build environments for selected configurations.
1144 #
1145 ###################################################
1146
1147 for variant_path in variant_paths:
1148     if not GetOption('silent'):
1149         print("Building in", variant_path)
1150
1151     # Make a copy of the build-root environment to use for this config.
1152     env = main.Clone()
1153     env['BUILDDIR'] = variant_path
1154
1155     # variant_dir is the tail component of build path, and is used to
1156     # determine the build parameters (e.g., 'X86')
1157     (build_root, variant_dir) = splitpath(variant_path)
1158
1159     # Set env variables according to the build directory config.
1160     sticky_vars.files = []
1161     # Variables for $BUILD_ROOT/$VARIANT_DIR are stored in
1162     # $BUILD_ROOT/variables/$VARIANT_DIR so you can nuke
1163     # $BUILD_ROOT/$VARIANT_DIR without losing your variables settings.
1164     current_vars_file = joinpath(build_root, 'variables', variant_dir)
1165     if isfile(current_vars_file):
1166         sticky_vars.files.append(current_vars_file)
1167         if not GetOption('silent'):
1168             print("Using saved variables file %s" % current_vars_file)
1169     elif variant_dir in ext_build_dirs:
1170         # Things in ext are built without a variant directory.
1171         continue
1172     else:
1173         # Build dir-specific variables file doesn't exist.
1174
1175         # Make sure the directory is there so we can create it later
1176         opt_dir = dirname(current_vars_file)
1177         if not isdir(opt_dir):
1178             mkdir(opt_dir)
1179
1180         # Get default build variables from source tree.  Variables are
1181         # normally determined by name of $VARIANT_DIR, but can be
1182         # overridden by '--default=' arg on command line.
1183         default = GetOption('default')
1184         opts_dir = joinpath(main.root.abspath, 'build_opts')
1185         if default:
1186             default_vars_files = [joinpath(build_root, 'variables', default),
1187                                   joinpath(opts_dir, default)]
1188         else:
1189             default_vars_files = [joinpath(opts_dir, variant_dir)]
1190         existing_files = filter(isfile, default_vars_files)
1191         if existing_files:
1192             default_vars_file = existing_files[0]
1193             sticky_vars.files.append(default_vars_file)
1194             print("Variables file %s not found,\n  using defaults in %s"
1195                   % (current_vars_file, default_vars_file))
1196         else:
1197             error("Cannot find variables file %s or default file(s) %s"
1198                   % (current_vars_file, ' or '.join(default_vars_files)))
1199             Exit(1)
1200
1201     # Apply current variable settings to env
1202     sticky_vars.Update(env)
1203
1204     help_texts["local_vars"] += \
1205         "Build variables for %s:\n" % variant_dir \
1206                  + sticky_vars.GenerateHelpText(env)
1207
1208     # Process variable settings.
1209
1210     if not have_fenv and env['USE_FENV']:
1211         warning("<fenv.h> not available; forcing USE_FENV to False in",
1212                 variant_dir + ".")
1213         env['USE_FENV'] = False
1214
1215     if not env['USE_FENV']:
1216         warning("No IEEE FP rounding mode control in", variant_dir + ".\n"
1217                 "FP results may deviate slightly from other platforms.")
1218
1219     if not have_png and env['USE_PNG']:
1220         warning("<png.h> not available; forcing USE_PNG to False in",
1221                 variant_dir + ".")
1222         env['USE_PNG'] = False
1223
1224     if env['USE_PNG']:
1225         env.Append(LIBS=['png'])
1226
1227     if env['EFENCE']:
1228         env.Append(LIBS=['efence'])
1229
1230     if env['USE_KVM']:
1231         if not have_kvm:
1232             warning("Can not enable KVM, host seems to lack KVM support")
1233             env['USE_KVM'] = False
1234         elif not is_isa_kvm_compatible(env['TARGET_ISA']):
1235             print("Info: KVM support disabled due to unsupported host and "
1236                   "target ISA combination")
1237             env['USE_KVM'] = False
1238
1239     if env['USE_TUNTAP']:
1240         if not have_tuntap:
1241             warning("Can't connect EtherTap with a tap device.")
1242             env['USE_TUNTAP'] = False
1243
1244     if env['BUILD_GPU']:
1245         env.Append(CPPDEFINES=['BUILD_GPU'])
1246
1247     # Warn about missing optional functionality
1248     if env['USE_KVM']:
1249         if not main['HAVE_PERF_ATTR_EXCLUDE_HOST']:
1250             warning("perf_event headers lack support for the exclude_host "
1251                     "attribute. KVM instruction counts will be inaccurate.")
1252
1253     # Save sticky variable settings back to current variables file
1254     sticky_vars.Save(current_vars_file, env)
1255
1256     if env['USE_SSE2']:
1257         env.Append(CCFLAGS=['-msse2'])
1258
1259     env.Append(CCFLAGS='$CCFLAGS_EXTRA')
1260     env.Append(LINKFLAGS='$LDFLAGS_EXTRA')
1261
1262     # The src/SConscript file sets up the build rules in 'env' according
1263     # to the configured variables.  It returns a list of environments,
1264     # one for each variant build (debug, opt, etc.)
1265     SConscript('src/SConscript', variant_dir = variant_path, exports = 'env')
1266
1267 # base help text
1268 Help('''
1269 Usage: scons [scons options] [build variables] [target(s)]
1270
1271 Extra scons options:
1272 %(options)s
1273
1274 Global build variables:
1275 %(global_vars)s
1276
1277 %(local_vars)s
1278 ''' % help_texts)