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 atexit
  82 import itertools
  83 import os
  84 import re
  85 import shutil
  86 import subprocess
  87 import sys
  88
  89 from os import mkdir, environ
  90 from os.path import abspath, basename, dirname, expanduser, normpath
  91 from os.path import exists,  isdir, isfile
  92 from os.path import join as joinpath, split as splitpath
  93 from re import match
  94
  95 # SCons includes
  96 import SCons
  97 import SCons.Node
  98 import SCons.Node.FS
  99
 100 from m5.util import compareVersions, readCommand, readCommandWithReturn
 101
 102 help_texts = {
 103     "options" : "",
 104     "global_vars" : "",
 105     "local_vars" : ""
 106 }
 107
 108 Export("help_texts")
 109
 110
 111 # There's a bug in scons in that (1) by default, the help texts from
 112 # AddOption() are supposed to be displayed when you type 'scons -h'
 113 # and (2) you can override the help displayed by 'scons -h' using the
 114 # Help() function, but these two features are incompatible: once
 115 # you've overridden the help text using Help(), there's no way to get
 116 # at the help texts from AddOptions.  See:
 117 #     http://scons.tigris.org/issues/show_bug.cgi?id=2356
 118 #     http://scons.tigris.org/issues/show_bug.cgi?id=2611
 119 # This hack lets us extract the help text from AddOptions and
 120 # re-inject it via Help().  Ideally someday this bug will be fixed and
 121 # we can just use AddOption directly.
 122 def AddLocalOption(*args, **kwargs):
 123     col_width = 30
 124
 125     help = "  " + ", ".join(args)
 126     if "help" in kwargs:
 127         length = len(help)
 128         if length >= col_width:
 129             help += "\n" + " " * col_width
 130         else:
 131             help += " " * (col_width - length)
 132         help += kwargs["help"]
 133     help_texts["options"] += help + "\n"
 134
 135     AddOption(*args, **kwargs)
 136
 137 AddLocalOption('--colors', dest='use_colors', action='store_true',
 138                help="Add color to abbreviated scons output")
 139 AddLocalOption('--no-colors', dest='use_colors', action='store_false',
 140                help="Don't add color to abbreviated scons output")
 141 AddLocalOption('--with-cxx-config', dest='with_cxx_config',
 142                action='store_true',
 143                help="Build with support for C++-based configuration")
 144 AddLocalOption('--default', dest='default', type='string', action='store',
 145                help='Override which build_opts file to use for defaults')
 146 AddLocalOption('--ignore-style', dest='ignore_style', action='store_true',
 147                help='Disable style checking hooks')
 148 AddLocalOption('--gold-linker', dest='gold_linker', action='store_true',
 149                help='Use the gold linker')
 150 AddLocalOption('--no-lto', dest='no_lto', action='store_true',
 151                help='Disable Link-Time Optimization for fast')
 152 AddLocalOption('--force-lto', dest='force_lto', action='store_true',
 153                help='Use Link-Time Optimization instead of partial linking' +
 154                     ' when the compiler doesn\'t support using them together.')
 155 AddLocalOption('--update-ref', dest='update_ref', action='store_true',
 156                help='Update test reference outputs')
 157 AddLocalOption('--verbose', dest='verbose', action='store_true',
 158                help='Print full tool command lines')
 159 AddLocalOption('--without-python', dest='without_python',
 160                action='store_true',
 161                help='Build without Python configuration support')
 162 AddLocalOption('--without-tcmalloc', dest='without_tcmalloc',
 163                action='store_true',
 164                help='Disable linking against tcmalloc')
 165 AddLocalOption('--with-ubsan', dest='with_ubsan', action='store_true',
 166                help='Build with Undefined Behavior Sanitizer if available')
 167 AddLocalOption('--with-asan', dest='with_asan', action='store_true',
 168                help='Build with Address Sanitizer if available')
 169 AddLocalOption('--with-systemc-tests', dest='with_systemc_tests',
 170                action='store_true', help='Build systemc tests')
 171
 172 from gem5_scons import Transform, error, warning, summarize_warnings
 173
 174 if GetOption('no_lto') and GetOption('force_lto'):
 175     error('--no-lto and --force-lto are mutually exclusive')
 176
 177 ########################################################################
 178 #
 179 # Set up the main build environment.
 180 #
 181 ########################################################################
 182
 183 main = Environment()
 184
 185 from gem5_scons.util import get_termcap
 186 termcap = get_termcap()
 187
 188 main_dict_keys = main.Dictionary().keys()
 189
 190 # Check that we have a C/C++ compiler
 191 if not ('CC' in main_dict_keys and 'CXX' in main_dict_keys):
 192     error("No C++ compiler installed (package g++ on Ubuntu and RedHat)")
 193
 194 ###################################################
 195 #
 196 # Figure out which configurations to set up based on the path(s) of
 197 # the target(s).
 198 #
 199 ###################################################
 200
 201 # Find default configuration & binary.
 202 Default(environ.get('M5_DEFAULT_BINARY', 'build/ARM/gem5.debug'))
 203
 204 # helper function: find last occurrence of element in list
 205 def rfind(l, elt, offs = -1):
 206     for i in range(len(l)+offs, 0, -1):
 207         if l[i] == elt:
 208             return i
 209     raise ValueError("element not found")
 210
 211 # Take a list of paths (or SCons Nodes) and return a list with all
 212 # paths made absolute and ~-expanded.  Paths will be interpreted
 213 # relative to the launch directory unless a different root is provided
 214 def makePathListAbsolute(path_list, root=GetLaunchDir()):
 215     return [abspath(joinpath(root, expanduser(str(p))))
 216             for p in path_list]
 217
 218 # Each target must have 'build' in the interior of the path; the
 219 # directory below this will determine the build parameters.  For
 220 # example, for target 'foo/bar/build/X86/arch/x86/blah.do' we
 221 # recognize that X86 specifies the configuration because it
 222 # follow 'build' in the build path.
 223
 224 # The funky assignment to "[:]" is needed to replace the list contents
 225 # in place rather than reassign the symbol to a new list, which
 226 # doesn't work (obviously!).
 227 BUILD_TARGETS[:] = makePathListAbsolute(BUILD_TARGETS)
 228
 229 # Generate a list of the unique build roots and configs that the
 230 # collected targets reference.
 231 variant_paths = []
 232 build_root = None
 233 for t in BUILD_TARGETS:
 234     path_dirs = t.split('/')
 235     try:
 236         build_top = rfind(path_dirs, 'build', -2)
 237     except:
 238         error("No non-leaf 'build' dir found on target path.", t)
 239     this_build_root = joinpath('/',*path_dirs[:build_top+1])
 240     if not build_root:
 241         build_root = this_build_root
 242     else:
 243         if this_build_root != build_root:
 244             error("build targets not under same build root\n"
 245                   "  %s\n  %s" % (build_root, this_build_root))
 246     variant_path = joinpath('/',*path_dirs[:build_top+2])
 247     if variant_path not in variant_paths:
 248         variant_paths.append(variant_path)
 249
 250 # Make sure build_root exists (might not if this is the first build there)
 251 if not isdir(build_root):
 252     mkdir(build_root)
 253 main['BUILDROOT'] = build_root
 254
 255 Export('main')
 256
 257 main.SConsignFile(joinpath(build_root, "sconsign"))
 258
 259 # Default duplicate option is to use hard links, but this messes up
 260 # when you use emacs to edit a file in the target dir, as emacs moves
 261 # file to file~ then copies to file, breaking the link.  Symbolic
 262 # (soft) links work better.
 263 main.SetOption('duplicate', 'soft-copy')
 264
 265 #
 266 # Set up global sticky variables... these are common to an entire build
 267 # tree (not specific to a particular build like X86)
 268 #
 269
 270 global_vars_file = joinpath(build_root, 'variables.global')
 271
 272 global_vars = Variables(global_vars_file, args=ARGUMENTS)
 273
 274 global_vars.AddVariables(
 275     ('CC', 'C compiler', environ.get('CC', main['CC'])),
 276     ('CXX', 'C++ compiler', environ.get('CXX', main['CXX'])),
 277     ('CCFLAGS_EXTRA', 'Extra C and C++ compiler flags', ''),
 278     ('LDFLAGS_EXTRA', 'Extra linker flags', ''),
 279     ('PYTHON_CONFIG', 'Python config binary to use',
 280      [ 'python2.7-config', 'python-config', 'python3-config' ]),
 281     ('PROTOC', 'protoc tool', environ.get('PROTOC', 'protoc')),
 282     ('BATCH', 'Use batch pool for build and tests', False),
 283     ('BATCH_CMD', 'Batch pool submission command name', 'qdo'),
 284     ('M5_BUILD_CACHE', 'Cache built objects in this directory', False),
 285     ('EXTRAS', 'Add extra directories to the compilation', '')
 286     )
 287
 288 # Update main environment with values from ARGUMENTS & global_vars_file
 289 global_vars.Update(main)
 290 help_texts["global_vars"] += global_vars.GenerateHelpText(main)
 291
 292 # Save sticky variable settings back to current variables file
 293 global_vars.Save(global_vars_file, main)
 294
 295 # Parse EXTRAS variable to build list of all directories where we're
 296 # look for sources etc.  This list is exported as extras_dir_list.
 297 base_dir = main.srcdir.abspath
 298 if main['EXTRAS']:
 299     extras_dir_list = makePathListAbsolute(main['EXTRAS'].split(':'))
 300 else:
 301     extras_dir_list = []
 302
 303 Export('base_dir')
 304 Export('extras_dir_list')
 305
 306 # the ext directory should be on the #includes path
 307 main.Append(CPPPATH=[Dir('ext')])
 308
 309 # Add shared top-level headers
 310 main.Prepend(CPPPATH=Dir('include'))
 311
 312 if GetOption('verbose'):
 313     def MakeAction(action, string, *args, **kwargs):
 314         return Action(action, *args, **kwargs)
 315 else:
 316     MakeAction = Action
 317     main['CCCOMSTR']        = Transform("CC")
 318     main['CXXCOMSTR']       = Transform("CXX")
 319     main['ASCOMSTR']        = Transform("AS")
 320     main['ARCOMSTR']        = Transform("AR", 0)
 321     main['LINKCOMSTR']      = Transform("LINK", 0)
 322     main['SHLINKCOMSTR']    = Transform("SHLINK", 0)
 323     main['RANLIBCOMSTR']    = Transform("RANLIB", 0)
 324     main['M4COMSTR']        = Transform("M4")
 325     main['SHCCCOMSTR']      = Transform("SHCC")
 326     main['SHCXXCOMSTR']     = Transform("SHCXX")
 327 Export('MakeAction')
 328
 329 # Initialize the Link-Time Optimization (LTO) flags
 330 main['LTO_CCFLAGS'] = []
 331 main['LTO_LDFLAGS'] = []
 332
 333 # According to the readme, tcmalloc works best if the compiler doesn't
 334 # assume that we're using the builtin malloc and friends. These flags
 335 # are compiler-specific, so we need to set them after we detect which
 336 # compiler we're using.
 337 main['TCMALLOC_CCFLAGS'] = []
 338
 339 CXX_version = readCommand([main['CXX'],'--version'], exception=False)
 340 CXX_V = readCommand([main['CXX'],'-V'], exception=False)
 341
 342 main['GCC'] = CXX_version and CXX_version.find('g++') >= 0
 343 main['CLANG'] = CXX_version and CXX_version.find('clang') >= 0
 344 if main['GCC'] + main['CLANG'] > 1:
 345     error('Two compilers enabled at once?')
 346
 347 # Set up default C++ compiler flags
 348 if main['GCC'] or main['CLANG']:
 349     # As gcc and clang share many flags, do the common parts here
 350     main.Append(CCFLAGS=['-pipe'])
 351     main.Append(CCFLAGS=['-fno-strict-aliasing'])
 352     # Enable -Wall and -Wextra and then disable the few warnings that
 353     # we consistently violate
 354     main.Append(CCFLAGS=['-Wall', '-Wundef', '-Wextra',
 355                          '-Wno-sign-compare', '-Wno-unused-parameter'])
 356     # We always compile using C++11
 357     main.Append(CXXFLAGS=['-std=c++11'])
 358     if sys.platform.startswith('freebsd'):
 359         main.Append(CCFLAGS=['-I/usr/local/include'])
 360         main.Append(CXXFLAGS=['-I/usr/local/include'])
 361
 362     # On Mac OS X/Darwin the default linker doesn't support the
 363     # option --as-needed
 364     if sys.platform != "darwin":
 365         main.Append(LINKFLAGS='-Wl,--as-needed')
 366     main['FILTER_PSHLINKFLAGS'] = lambda x: str(x).replace(' -shared', '')
 367     main['PSHLINKFLAGS'] = main.subst('${FILTER_PSHLINKFLAGS(SHLINKFLAGS)}')
 368     if GetOption('gold_linker'):
 369         main.Append(LINKFLAGS='-fuse-ld=gold')
 370     main['PLINKFLAGS'] = main.get('LINKFLAGS')
 371     shared_partial_flags = ['-r', '-nostdlib']
 372     main.Append(PSHLINKFLAGS=shared_partial_flags)
 373     main.Append(PLINKFLAGS=shared_partial_flags)
 374
 375     # Treat warnings as errors but white list some warnings that we
 376     # want to allow (e.g., deprecation warnings).
 377     main.Append(CCFLAGS=['-Werror',
 378                          '-Wno-error=deprecated-declarations',
 379                          '-Wno-error=deprecated',
 380                         ])
 381 else:
 382     error('\n'.join((
 383           "Don't know what compiler options to use for your compiler.",
 384           "compiler: " + main['CXX'],
 385           "version: " + CXX_version.replace('\n', '<nl>') if
 386                 CXX_version else 'COMMAND NOT FOUND!',
 387           "If you're trying to use a compiler other than GCC",
 388           "or clang, there appears to be something wrong with your",
 389           "environment.",
 390           "",
 391           "If you are trying to use a compiler other than those listed",
 392           "above you will need to ease fix SConstruct and ",
 393           "src/SConscript to support that compiler.")))
 394
 395 if main['GCC']:
 396     # Check for a supported version of gcc. >= 4.8 is chosen for its
 397     # level of c++11 support. See
 398     # http://gcc.gnu.org/projects/cxx0x.html for details.
 399     gcc_version = readCommand([main['CXX'], '-dumpversion'], exception=False)
 400     if compareVersions(gcc_version, "4.8") < 0:
 401         error('gcc version 4.8 or newer required.\n'
 402               'Installed version:', gcc_version)
 403         Exit(1)
 404
 405     main['GCC_VERSION'] = gcc_version
 406
 407     if compareVersions(gcc_version, '4.9') >= 0 and \
 408        compareVersions(gcc_version, '8.1') < 0:
 409         # Incremental linking with LTO is currently broken in gcc versions
 410         # 4.9 to 8.1.
 411         #
 412         # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67548
 413         #
 414         # gcc versions 6.0 and greater accept an -flinker-output flag which
 415         # selects what type of output the linker should generate. This is
 416         # necessary for incremental lto to work, but is also broken in
 417         # versions of gcc up to 8.1.
 418         #
 419         # https://gcc.gnu.org/gcc-6/changes.html
 420         # https://gcc.gnu.org/ml/gcc-patches/2015-11/msg03161.html
 421         # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69866
 422         main['BROKEN_INCREMENTAL_LTO'] = True
 423
 424     disable_lto = GetOption('no_lto')
 425     if not disable_lto and main.get('BROKEN_INCREMENTAL_LTO', False) and \
 426             not GetOption('force_lto'):
 427         warning('Your compiler doesn\'t support incremental linking and lto '
 428                 'at the same time, so lto is being disabled. To force lto on '
 429                 'anyway, use the --force-lto option. That will disable '
 430                 'partial linking.')
 431         disable_lto = True
 432
 433     # Add the appropriate Link-Time Optimization (LTO) flags
 434     # unless LTO is explicitly turned off. Note that these flags
 435     # are only used by the fast target.
 436     if not disable_lto:
 437         # Pass the LTO flag when compiling to produce GIMPLE
 438         # output, we merely create the flags here and only append
 439         # them later
 440         main['LTO_CCFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
 441
 442         # Use the same amount of jobs for LTO as we are running
 443         # scons with
 444         main['LTO_LDFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
 445
 446     main.Append(TCMALLOC_CCFLAGS=['-fno-builtin-malloc', '-fno-builtin-calloc',
 447                                   '-fno-builtin-realloc', '-fno-builtin-free'])
 448
 449 elif main['CLANG']:
 450     # Check for a supported version of clang, >= 3.1 is needed to
 451     # support similar features as gcc 4.8. See
 452     # http://clang.llvm.org/cxx_status.html for details
 453     clang_version_re = re.compile(".* version (\d+\.\d+)")
 454     clang_version_match = clang_version_re.search(CXX_version)
 455     if (clang_version_match):
 456         clang_version = clang_version_match.groups()[0]
 457         if compareVersions(clang_version, "3.1") < 0:
 458             error('clang version 3.1 or newer required.\n'
 459                   'Installed version:', clang_version)
 460     else:
 461         error('Unable to determine clang version.')
 462
 463     # clang has a few additional warnings that we disable, extraneous
 464     # parantheses are allowed due to Ruby's printing of the AST,
 465     # finally self assignments are allowed as the generated CPU code
 466     # is relying on this
 467     main.Append(CCFLAGS=['-Wno-parentheses',
 468                          '-Wno-self-assign',
 469                          # Some versions of libstdc++ (4.8?) seem to
 470                          # use struct hash and class hash
 471                          # interchangeably.
 472                          '-Wno-mismatched-tags',
 473                          ])
 474
 475     main.Append(TCMALLOC_CCFLAGS=['-fno-builtin'])
 476
 477     # On Mac OS X/Darwin we need to also use libc++ (part of XCode) as
 478     # opposed to libstdc++, as the later is dated.
 479     if sys.platform == "darwin":
 480         main.Append(CXXFLAGS=['-stdlib=libc++'])
 481         main.Append(LIBS=['c++'])
 482
 483     # On FreeBSD we need libthr.
 484     if sys.platform.startswith('freebsd'):
 485         main.Append(LIBS=['thr'])
 486
 487 # Add sanitizers flags
 488 sanitizers=[]
 489 if GetOption('with_ubsan'):
 490     # Only gcc >= 4.9 supports UBSan, so check both the version
 491     # and the command-line option before adding the compiler and
 492     # linker flags.
 493     if not main['GCC'] or compareVersions(main['GCC_VERSION'], '4.9') >= 0:
 494         sanitizers.append('undefined')
 495 if GetOption('with_asan'):
 496     # Available for gcc >= 4.8 or llvm >= 3.1 both a requirement
 497     # by the build system
 498     sanitizers.append('address')
 499     suppressions_file = Dir('util').File('lsan-suppressions').get_abspath()
 500     suppressions_opt = 'suppressions=%s' % suppressions_file
 501     main['ENV']['LSAN_OPTIONS'] = ':'.join([suppressions_opt,
 502                                             'print_suppressions=0'])
 503     print()
 504     warning('To suppress false positive leaks, set the LSAN_OPTIONS '
 505             'environment variable to "%s" when running gem5' %
 506             suppressions_opt)
 507     warning('LSAN_OPTIONS=suppressions=%s' % suppressions_opt)
 508     print()
 509 if sanitizers:
 510     sanitizers = ','.join(sanitizers)
 511     if main['GCC'] or main['CLANG']:
 512         main.Append(CCFLAGS=['-fsanitize=%s' % sanitizers,
 513                              '-fno-omit-frame-pointer'],
 514                     LINKFLAGS='-fsanitize=%s' % sanitizers)
 515     else:
 516         warning("Don't know how to enable %s sanitizer(s) for your "
 517                 "compiler." % sanitizers)
 518
 519 # Set up common yacc/bison flags (needed for Ruby)
 520 main['YACCFLAGS'] = '-d'
 521 main['YACCHXXFILESUFFIX'] = '.hh'
 522
 523 # Do this after we save setting back, or else we'll tack on an
 524 # extra 'qdo' every time we run scons.
 525 if main['BATCH']:
 526     main['CC']     = main['BATCH_CMD'] + ' ' + main['CC']
 527     main['CXX']    = main['BATCH_CMD'] + ' ' + main['CXX']
 528     main['AS']     = main['BATCH_CMD'] + ' ' + main['AS']
 529     main['AR']     = main['BATCH_CMD'] + ' ' + main['AR']
 530     main['RANLIB'] = main['BATCH_CMD'] + ' ' + main['RANLIB']
 531
 532 if sys.platform == 'cygwin':
 533     # cygwin has some header file issues...
 534     main.Append(CCFLAGS=["-Wno-uninitialized"])
 535
 536
 537 have_pkg_config = readCommand(['pkg-config', '--version'], exception='')
 538
 539 # Check for the protobuf compiler
 540 try:
 541     main['HAVE_PROTOC'] = True
 542     protoc_version = readCommand([main['PROTOC'], '--version']).split()
 543
 544     # First two words should be "libprotoc x.y.z"
 545     if len(protoc_version) < 2 or protoc_version[0] != 'libprotoc':
 546         warning('Protocol buffer compiler (protoc) not found.\n'
 547                 'Please install protobuf-compiler for tracing support.')
 548         main['HAVE_PROTOC'] = False
 549     else:
 550         # Based on the availability of the compress stream wrappers,
 551         # require 2.1.0
 552         min_protoc_version = '2.1.0'
 553         if compareVersions(protoc_version[1], min_protoc_version) < 0:
 554             warning('protoc version', min_protoc_version,
 555                     'or newer required.\n'
 556                     'Installed version:', protoc_version[1])
 557             main['HAVE_PROTOC'] = False
 558         else:
 559             # Attempt to determine the appropriate include path and
 560             # library path using pkg-config, that means we also need to
 561             # check for pkg-config. Note that it is possible to use
 562             # protobuf without the involvement of pkg-config. Later on we
 563             # check go a library config check and at that point the test
 564             # will fail if libprotobuf cannot be found.
 565             if have_pkg_config:
 566                 try:
 567                     # Attempt to establish what linking flags to add for
 568                     # protobuf
 569                     # using pkg-config
 570                     main.ParseConfig(
 571                             'pkg-config --cflags --libs-only-L protobuf')
 572                 except:
 573                     warning('pkg-config could not get protobuf flags.')
 574 except Exception as e:
 575     warning('While checking protoc version:', str(e))
 576     main['HAVE_PROTOC'] = False
 577
 578 # Check for 'timeout' from GNU coreutils. If present, regressions will
 579 # be run with a time limit. We require version 8.13 since we rely on
 580 # support for the '--foreground' option.
 581 if sys.platform.startswith('freebsd'):
 582     timeout_lines = readCommand(['gtimeout', '--version'],
 583                                 exception='').splitlines()
 584 else:
 585     timeout_lines = readCommand(['timeout', '--version'],
 586                                 exception='').splitlines()
 587 # Get the first line and tokenize it
 588 timeout_version = timeout_lines[0].split() if timeout_lines else []
 589 main['TIMEOUT'] =  timeout_version and \
 590     compareVersions(timeout_version[-1], '8.13') >= 0
 591
 592 # Add a custom Check function to test for structure members.
 593 def CheckMember(context, include, decl, member, include_quotes="<>"):
 594     context.Message("Checking for member %s in %s..." %
 595                     (member, decl))
 596     text = """
 597 #include %(header)s
 598 int main(){
 599   %(decl)s test;
 600   (void)test.%(member)s;
 601   return 0;
 602 };
 603 """ % { "header" : include_quotes[0] + include + include_quotes[1],
 604         "decl" : decl,
 605         "member" : member,
 606         }
 607
 608     ret = context.TryCompile(text, extension=".cc")
 609     context.Result(ret)
 610     return ret
 611
 612 # Platform-specific configuration.  Note again that we assume that all
 613 # builds under a given build root run on the same host platform.
 614 conf = Configure(main,
 615                  conf_dir = joinpath(build_root, '.scons_config'),
 616                  log_file = joinpath(build_root, 'scons_config.log'),
 617                  custom_tests = {
 618         'CheckMember' : CheckMember,
 619         })
 620
 621 # Check if we should compile a 64 bit binary on Mac OS X/Darwin
 622 try:
 623     import platform
 624     uname = platform.uname()
 625     if uname[0] == 'Darwin' and compareVersions(uname[2], '9.0.0') >= 0:
 626         if int(readCommand('sysctl -n hw.cpu64bit_capable')[0]):
 627             main.Append(CCFLAGS=['-arch', 'x86_64'])
 628             main.Append(CFLAGS=['-arch', 'x86_64'])
 629             main.Append(LINKFLAGS=['-arch', 'x86_64'])
 630             main.Append(ASFLAGS=['-arch', 'x86_64'])
 631 except:
 632     pass
 633
 634 # Recent versions of scons substitute a "Null" object for Configure()
 635 # when configuration isn't necessary, e.g., if the "--help" option is
 636 # present.  Unfortuantely this Null object always returns false,
 637 # breaking all our configuration checks.  We replace it with our own
 638 # more optimistic null object that returns True instead.
 639 if not conf:
 640     def NullCheck(*args, **kwargs):
 641         return True
 642
 643     class NullConf:
 644         def __init__(self, env):
 645             self.env = env
 646         def Finish(self):
 647             return self.env
 648         def __getattr__(self, mname):
 649             return NullCheck
 650
 651     conf = NullConf(main)
 652
 653 # Cache build files in the supplied directory.
 654 if main['M5_BUILD_CACHE']:
 655     print('Using build cache located at', main['M5_BUILD_CACHE'])
 656     CacheDir(main['M5_BUILD_CACHE'])
 657
 658 main['USE_PYTHON'] = not GetOption('without_python')
 659 if main['USE_PYTHON']:
 660     # Find Python include and library directories for embedding the
 661     # interpreter. We rely on python-config to resolve the appropriate
 662     # includes and linker flags. ParseConfig does not seem to understand
 663     # the more exotic linker flags such as -Xlinker and -export-dynamic so
 664     # we add them explicitly below. If you want to link in an alternate
 665     # version of python, see above for instructions on how to invoke
 666     # scons with the appropriate PATH set.
 667
 668     python_config = main.Detect(main['PYTHON_CONFIG'])
 669     if python_config is None:
 670         error("Can't find a suitable python-config, tried %s" % \
 671               main['PYTHON_CONFIG'])
 672
 673     print("Info: Using Python config: %s" % (python_config, ))
 674     py_includes = readCommand([python_config, '--includes'],
 675                               exception='').split()
 676     py_includes = list(filter(
 677         lambda s: match(r'.*\/include\/.*',s), py_includes))
 678     # Strip the -I from the include folders before adding them to the
 679     # CPPPATH
 680     py_includes = list(map(
 681         lambda s: s[2:] if s.startswith('-I') else s, py_includes))
 682     main.Append(CPPPATH=py_includes)
 683
 684     # Read the linker flags and split them into libraries and other link
 685     # flags. The libraries are added later through the call the CheckLib.
 686     # Note: starting in Python 3.8 the --embed flag is required to get the
 687     # -lpython3.8 linker flag
 688     retcode, cmd_stdout = readCommandWithReturn(
 689         [python_config, '--ldflags', '--embed'], exception='')
 690     if retcode != 0:
 691         # If --embed isn't detected then we're running python <3.8
 692         retcode, cmd_stdout = readCommandWithReturn(
 693             [python_config, '--ldflags'], exception='')
 694
 695     # Checking retcode again
 696     if retcode != 0:
 697         error("Failing on python-config --ldflags command")
 698
 699     py_ld_flags = cmd_stdout.split()
 700
 701     py_libs = []
 702     for lib in py_ld_flags:
 703          if not lib.startswith('-l'):
 704              main.Append(LINKFLAGS=[lib])
 705          else:
 706              lib = lib[2:]
 707              if lib not in py_libs:
 708                  py_libs.append(lib)
 709
 710     # verify that this stuff works
 711     if not conf.CheckHeader('Python.h', '<>'):
 712         error("Check failed for Python.h header in",
 713                 ' '.join(py_includes), "\n"
 714               "Two possible reasons:\n"
 715               "1. Python headers are not installed (You can install the "
 716               "package python-dev on Ubuntu and RedHat)\n"
 717               "2. SCons is using a wrong C compiler. This can happen if "
 718               "CC has the wrong value.\n"
 719               "CC = %s" % main['CC'])
 720
 721     for lib in py_libs:
 722         if not conf.CheckLib(lib):
 723             error("Can't find library %s required by python." % lib)
 724
 725 main.Prepend(CPPPATH=Dir('ext/pybind11/include/'))
 726 # Bare minimum environment that only includes python
 727 base_py_env = main.Clone()
 728
 729 # On Solaris you need to use libsocket for socket ops
 730 if not conf.CheckLibWithHeader(None, 'sys/socket.h', 'C++', 'accept(0,0,0);'):
 731    if not conf.CheckLibWithHeader('socket', 'sys/socket.h',
 732                                   'C++', 'accept(0,0,0);'):
 733        error("Can't find library with socket calls (e.g. accept()).")
 734
 735 # Check for zlib.  If the check passes, libz will be automatically
 736 # added to the LIBS environment variable.
 737 if not conf.CheckLibWithHeader('z', 'zlib.h', 'C++','zlibVersion();'):
 738     error('Did not find needed zlib compression library '
 739           'and/or zlib.h header file.\n'
 740           'Please install zlib and try again.')
 741
 742 # If we have the protobuf compiler, also make sure we have the
 743 # development libraries. If the check passes, libprotobuf will be
 744 # automatically added to the LIBS environment variable. After
 745 # this, we can use the HAVE_PROTOBUF flag to determine if we have
 746 # got both protoc and libprotobuf available.
 747 main['HAVE_PROTOBUF'] = main['HAVE_PROTOC'] and \
 748     conf.CheckLibWithHeader('protobuf', 'google/protobuf/message.h',
 749                             'C++', 'GOOGLE_PROTOBUF_VERIFY_VERSION;')
 750
 751 # Valgrind gets much less confused if you tell it when you're using
 752 # alternative stacks.
 753 main['HAVE_VALGRIND'] = conf.CheckCHeader('valgrind/valgrind.h')
 754
 755 # If we have the compiler but not the library, print another warning.
 756 if main['HAVE_PROTOC'] and not main['HAVE_PROTOBUF']:
 757     warning('Did not find protocol buffer library and/or headers.\n'
 758             'Please install libprotobuf-dev for tracing support.')
 759
 760 # Check for librt.
 761 have_posix_clock = \
 762     conf.CheckLibWithHeader(None, 'time.h', 'C',
 763                             'clock_nanosleep(0,0,NULL,NULL);') or \
 764     conf.CheckLibWithHeader('rt', 'time.h', 'C',
 765                             'clock_nanosleep(0,0,NULL,NULL);')
 766
 767 have_posix_timers = \
 768     conf.CheckLibWithHeader([None, 'rt'], [ 'time.h', 'signal.h' ], 'C',
 769                             'timer_create(CLOCK_MONOTONIC, NULL, NULL);')
 770
 771 if not GetOption('without_tcmalloc'):
 772     if conf.CheckLib('tcmalloc'):
 773         main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
 774     elif conf.CheckLib('tcmalloc_minimal'):
 775         main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
 776     else:
 777         warning("You can get a 12% performance improvement by "
 778                 "installing tcmalloc (libgoogle-perftools-dev package "
 779                 "on Ubuntu or RedHat).")
 780
 781
 782 # Detect back trace implementations. The last implementation in the
 783 # list will be used by default.
 784 backtrace_impls = [ "none" ]
 785
 786 backtrace_checker = 'char temp;' + \
 787     ' backtrace_symbols_fd((void*)&temp, 0, 0);'
 788 if conf.CheckLibWithHeader(None, 'execinfo.h', 'C', backtrace_checker):
 789     backtrace_impls.append("glibc")
 790 elif conf.CheckLibWithHeader('execinfo', 'execinfo.h', 'C',
 791                              backtrace_checker):
 792     # NetBSD and FreeBSD need libexecinfo.
 793     backtrace_impls.append("glibc")
 794     main.Append(LIBS=['execinfo'])
 795
 796 if backtrace_impls[-1] == "none":
 797     default_backtrace_impl = "none"
 798     warning("No suitable back trace implementation found.")
 799
 800 if not have_posix_clock:
 801     warning("Can't find library for POSIX clocks.")
 802
 803 # Check for <fenv.h> (C99 FP environment control)
 804 have_fenv = conf.CheckHeader('fenv.h', '<>')
 805 if not have_fenv:
 806     warning("Header file <fenv.h> not found.\n"
 807             "This host has no IEEE FP rounding mode control.")
 808
 809 # Check for <png.h> (libpng library needed if wanting to dump
 810 # frame buffer image in png format)
 811 have_png = conf.CheckHeader('png.h', '<>')
 812 if not have_png:
 813     warning("Header file <png.h> not found.\n"
 814             "This host has no libpng library.\n"
 815             "Disabling support for PNG framebuffers.")
 816
 817 # Check if we should enable KVM-based hardware virtualization. The API
 818 # we rely on exists since version 2.6.36 of the kernel, but somehow
 819 # the KVM_API_VERSION does not reflect the change. We test for one of
 820 # the types as a fall back.
 821 have_kvm = conf.CheckHeader('linux/kvm.h', '<>')
 822 if not have_kvm:
 823     print("Info: Compatible header file <linux/kvm.h> not found, "
 824           "disabling KVM support.")
 825
 826 # Check if the TUN/TAP driver is available.
 827 have_tuntap = conf.CheckHeader('linux/if_tun.h', '<>')
 828 if not have_tuntap:
 829     print("Info: Compatible header file <linux/if_tun.h> not found.")
 830
 831 # x86 needs support for xsave. We test for the structure here since we
 832 # won't be able to run new tests by the time we know which ISA we're
 833 # targeting.
 834 have_kvm_xsave = conf.CheckTypeSize('struct kvm_xsave',
 835                                     '#include <linux/kvm.h>') != 0
 836
 837 # Check if the requested target ISA is compatible with the host
 838 def is_isa_kvm_compatible(isa):
 839     try:
 840         import platform
 841         host_isa = platform.machine()
 842     except:
 843         warning("Failed to determine host ISA.")
 844         return False
 845
 846     if not have_posix_timers:
 847         warning("Can not enable KVM, host seems to lack support "
 848                 "for POSIX timers")
 849         return False
 850
 851     if isa == "arm":
 852         return host_isa in ( "armv7l", "aarch64" )
 853     elif isa == "x86":
 854         if host_isa != "x86_64":
 855             return False
 856
 857         if not have_kvm_xsave:
 858             warning("KVM on x86 requires xsave support in kernel headers.")
 859             return False
 860
 861         return True
 862     else:
 863         return False
 864
 865
 866 # Check if the exclude_host attribute is available. We want this to
 867 # get accurate instruction counts in KVM.
 868 main['HAVE_PERF_ATTR_EXCLUDE_HOST'] = conf.CheckMember(
 869     'linux/perf_event.h', 'struct perf_event_attr', 'exclude_host')
 870
 871 def check_hdf5():
 872     return \
 873         conf.CheckLibWithHeader('hdf5', 'hdf5.h', 'C',
 874                                 'H5Fcreate("", 0, 0, 0);') and \
 875         conf.CheckLibWithHeader('hdf5_cpp', 'H5Cpp.h', 'C++',
 876                                 'H5::H5File("", 0);')
 877
 878 def check_hdf5_pkg(name):
 879     print("Checking for %s using pkg-config..." % name, end="")
 880     if not have_pkg_config:
 881         print(" pkg-config not found")
 882         return False
 883
 884     try:
 885         main.ParseConfig('pkg-config --cflags-only-I --libs-only-L %s' % name)
 886         print(" yes")
 887         return True
 888     except:
 889         print(" no")
 890         return False
 891
 892 # Check if there is a pkg-config configuration for hdf5. If we find
 893 # it, setup the environment to enable linking and header inclusion. We
 894 # don't actually try to include any headers or link with hdf5 at this
 895 # stage.
 896 if not check_hdf5_pkg('hdf5-serial'):
 897     check_hdf5_pkg('hdf5')
 898
 899 # Check if the HDF5 libraries can be found. This check respects the
 900 # include path and library path provided by pkg-config. We perform
 901 # this check even if there isn't a pkg-config configuration for hdf5
 902 # since some installations don't use pkg-config.
 903 have_hdf5 = check_hdf5()
 904 if not have_hdf5:
 905     print("Warning: Couldn't find any HDF5 C++ libraries. Disabling")
 906     print("         HDF5 support.")
 907
 908 ######################################################################
 909 #
 910 # Finish the configuration
 911 #
 912 main = conf.Finish()
 913
 914 ######################################################################
 915 #
 916 # Collect all non-global variables
 917 #
 918
 919 # Define the universe of supported ISAs
 920 all_isa_list = [ ]
 921 all_gpu_isa_list = [ ]
 922 Export('all_isa_list')
 923 Export('all_gpu_isa_list')
 924
 925 class CpuModel(object):
 926     '''The CpuModel class encapsulates everything the ISA parser needs to
 927     know about a particular CPU model.'''
 928
 929     # Dict of available CPU model objects.  Accessible as CpuModel.dict.
 930     dict = {}
 931
 932     # Constructor.  Automatically adds models to CpuModel.dict.
 933     def __init__(self, name, default=False):
 934         self.name = name           # name of model
 935
 936         # This cpu is enabled by default
 937         self.default = default
 938
 939         # Add self to dict
 940         if name in CpuModel.dict:
 941             raise AttributeError("CpuModel '%s' already registered" % name)
 942         CpuModel.dict[name] = self
 943
 944 Export('CpuModel')
 945
 946 # Sticky variables get saved in the variables file so they persist from
 947 # one invocation to the next (unless overridden, in which case the new
 948 # value becomes sticky).
 949 sticky_vars = Variables(args=ARGUMENTS)
 950 Export('sticky_vars')
 951
 952 # Sticky variables that should be exported
 953 export_vars = []
 954 Export('export_vars')
 955
 956 # For Ruby
 957 all_protocols = []
 958 Export('all_protocols')
 959 protocol_dirs = []
 960 Export('protocol_dirs')
 961 slicc_includes = []
 962 Export('slicc_includes')
 963
 964 # Walk the tree and execute all SConsopts scripts that wil add to the
 965 # above variables
 966 if GetOption('verbose'):
 967     print("Reading SConsopts")
 968 for bdir in [ base_dir ] + extras_dir_list:
 969     if not isdir(bdir):
 970         error("Directory '%s' does not exist." % bdir)
 971     for root, dirs, files in os.walk(bdir):
 972         if 'SConsopts' in files:
 973             if GetOption('verbose'):
 974                 print("Reading", joinpath(root, 'SConsopts'))
 975             SConscript(joinpath(root, 'SConsopts'))
 976
 977 all_isa_list.sort()
 978 all_gpu_isa_list.sort()
 979
 980 sticky_vars.AddVariables(
 981     EnumVariable('TARGET_ISA', 'Target ISA', 'alpha', all_isa_list),
 982     EnumVariable('TARGET_GPU_ISA', 'Target GPU ISA', 'hsail', all_gpu_isa_list),
 983     ListVariable('CPU_MODELS', 'CPU models',
 984                  sorted(n for n,m in CpuModel.dict.items() if m.default),
 985                  sorted(CpuModel.dict.keys())),
 986     BoolVariable('EFENCE', 'Link with Electric Fence malloc debugger',
 987                  False),
 988     BoolVariable('USE_SSE2',
 989                  'Compile for SSE2 (-msse2) to get IEEE FP on x86 hosts',
 990                  False),
 991     BoolVariable('USE_POSIX_CLOCK', 'Use POSIX Clocks', have_posix_clock),
 992     BoolVariable('USE_FENV', 'Use <fenv.h> IEEE mode control', have_fenv),
 993     BoolVariable('USE_PNG',  'Enable support for PNG images', have_png),
 994     BoolVariable('CP_ANNOTATE', 'Enable critical path annotation capability',
 995                  False),
 996     BoolVariable('USE_KVM', 'Enable hardware virtualized (KVM) CPU models',
 997                  have_kvm),
 998     BoolVariable('USE_TUNTAP',
 999                  'Enable using a tap device to bridge to the host network',
1000                  have_tuntap),
1001     BoolVariable('BUILD_GPU', 'Build the compute-GPU model', False),
1002     EnumVariable('PROTOCOL', 'Coherence protocol for Ruby', 'None',
1003                   all_protocols),
1004     EnumVariable('BACKTRACE_IMPL', 'Post-mortem dump implementation',
1005                  backtrace_impls[-1], backtrace_impls),
1006     ('NUMBER_BITS_PER_SET', 'Max elements in set (default 64)',
1007                  64),
1008     BoolVariable('USE_HDF5', 'Enable the HDF5 support', have_hdf5),
1009     )
1010
1011 # These variables get exported to #defines in config/*.hh (see src/SConscript).
1012 export_vars += ['USE_FENV', 'TARGET_ISA', 'TARGET_GPU_ISA', 'CP_ANNOTATE',
1013                 'USE_POSIX_CLOCK', 'USE_KVM', 'USE_TUNTAP', 'PROTOCOL',
1014                 'HAVE_PROTOBUF', 'HAVE_VALGRIND',
1015                 'HAVE_PERF_ATTR_EXCLUDE_HOST', 'USE_PNG',
1016                 'NUMBER_BITS_PER_SET', 'USE_HDF5']
1017
1018 ###################################################
1019 #
1020 # Define a SCons builder for configuration flag headers.
1021 #
1022 ###################################################
1023
1024 # This function generates a config header file that #defines the
1025 # variable symbol to the current variable setting (0 or 1).  The source
1026 # operands are the name of the variable and a Value node containing the
1027 # value of the variable.
1028 def build_config_file(target, source, env):
1029     (variable, value) = [s.get_contents().decode('utf-8') for s in source]
1030     with open(str(target[0]), 'w') as f:
1031         print('#define', variable, value, file=f)
1032     return None
1033
1034 # Combine the two functions into a scons Action object.
1035 config_action = MakeAction(build_config_file, Transform("CONFIG H", 2))
1036
1037 # The emitter munges the source & target node lists to reflect what
1038 # we're really doing.
1039 def config_emitter(target, source, env):
1040     # extract variable name from Builder arg
1041     variable = str(target[0])
1042     # True target is config header file
1043     target = joinpath('config', variable.lower() + '.hh')
1044     val = env[variable]
1045     if isinstance(val, bool):
1046         # Force value to 0/1
1047         val = int(val)
1048     elif isinstance(val, str):
1049         val = '"' + val + '"'
1050
1051     # Sources are variable name & value (packaged in SCons Value nodes)
1052     return ([target], [Value(variable), Value(val)])
1053
1054 config_builder = Builder(emitter = config_emitter, action = config_action)
1055
1056 main.Append(BUILDERS = { 'ConfigFile' : config_builder })
1057
1058 ###################################################
1059 #
1060 # Builders for static and shared partially linked object files.
1061 #
1062 ###################################################
1063
1064 partial_static_builder = Builder(action=SCons.Defaults.LinkAction,
1065                                  src_suffix='$OBJSUFFIX',
1066                                  src_builder=['StaticObject', 'Object'],
1067                                  LINKFLAGS='$PLINKFLAGS',
1068                                  LIBS='')
1069
1070 def partial_shared_emitter(target, source, env):
1071     for tgt in target:
1072         tgt.attributes.shared = 1
1073     return (target, source)
1074 partial_shared_builder = Builder(action=SCons.Defaults.ShLinkAction,
1075                                  emitter=partial_shared_emitter,
1076                                  src_suffix='$SHOBJSUFFIX',
1077                                  src_builder='SharedObject',
1078                                  SHLINKFLAGS='$PSHLINKFLAGS',
1079                                  LIBS='')
1080
1081 main.Append(BUILDERS = { 'PartialShared' : partial_shared_builder,
1082                          'PartialStatic' : partial_static_builder })
1083
1084 def add_local_rpath(env, *targets):
1085     '''Set up an RPATH for a library which lives in the build directory.
1086
1087     The construction environment variable BIN_RPATH_PREFIX should be set to
1088     the relative path of the build directory starting from the location of the
1089     binary.'''
1090     for target in targets:
1091         target = env.Entry(target)
1092         if not isinstance(target, SCons.Node.FS.Dir):
1093             target = target.dir
1094         relpath = os.path.relpath(target.abspath, env['BUILDDIR'])
1095         components = [
1096             '\\$$ORIGIN',
1097             '${BIN_RPATH_PREFIX}',
1098             relpath
1099         ]
1100         env.Append(RPATH=[env.Literal(os.path.join(*components))])
1101
1102 if sys.platform != "darwin":
1103     main.Append(LINKFLAGS=Split('-z origin'))
1104
1105 main.AddMethod(add_local_rpath, 'AddLocalRPATH')
1106
1107 # builds in ext are shared across all configs in the build root.
1108 ext_dir = abspath(joinpath(str(main.root), 'ext'))
1109 ext_build_dirs = []
1110 for root, dirs, files in os.walk(ext_dir):
1111     if 'SConscript' in files:
1112         build_dir = os.path.relpath(root, ext_dir)
1113         ext_build_dirs.append(build_dir)
1114         main.SConscript(joinpath(root, 'SConscript'),
1115                         variant_dir=joinpath(build_root, build_dir))
1116
1117 gdb_xml_dir = joinpath(ext_dir, 'gdb-xml')
1118 Export('gdb_xml_dir')
1119
1120 ###################################################
1121 #
1122 # This builder and wrapper method are used to set up a directory with
1123 # switching headers. Those are headers which are in a generic location and
1124 # that include more specific headers from a directory chosen at build time
1125 # based on the current build settings.
1126 #
1127 ###################################################
1128
1129 def build_switching_header(target, source, env):
1130     path = str(target[0])
1131     subdir = str(source[0])
1132     dp, fp = os.path.split(path)
1133     dp = os.path.relpath(os.path.realpath(dp),
1134                          os.path.realpath(env['BUILDDIR']))
1135     with open(path, 'w') as hdr:
1136         print('#include "%s/%s/%s"' % (dp, subdir, fp), file=hdr)
1137
1138 switching_header_action = MakeAction(build_switching_header,
1139                                      Transform('GENERATE'))
1140
1141 switching_header_builder = Builder(action=switching_header_action,
1142                                    source_factory=Value,
1143                                    single_source=True)
1144
1145 main.Append(BUILDERS = { 'SwitchingHeader': switching_header_builder })
1146
1147 def switching_headers(self, headers, source):
1148     for header in headers:
1149         self.SwitchingHeader(header, source)
1150
1151 main.AddMethod(switching_headers, 'SwitchingHeaders')
1152
1153 ###################################################
1154 #
1155 # Define build environments for selected configurations.
1156 #
1157 ###################################################
1158
1159 for variant_path in variant_paths:
1160     if not GetOption('silent'):
1161         print("Building in", variant_path)
1162
1163     # Make a copy of the build-root environment to use for this config.
1164     env = main.Clone()
1165     env['BUILDDIR'] = variant_path
1166
1167     # variant_dir is the tail component of build path, and is used to
1168     # determine the build parameters (e.g., 'X86')
1169     (build_root, variant_dir) = splitpath(variant_path)
1170
1171     # Set env variables according to the build directory config.
1172     sticky_vars.files = []
1173     # Variables for $BUILD_ROOT/$VARIANT_DIR are stored in
1174     # $BUILD_ROOT/variables/$VARIANT_DIR so you can nuke
1175     # $BUILD_ROOT/$VARIANT_DIR without losing your variables settings.
1176     current_vars_file = joinpath(build_root, 'variables', variant_dir)
1177     if isfile(current_vars_file):
1178         sticky_vars.files.append(current_vars_file)
1179         if not GetOption('silent'):
1180             print("Using saved variables file %s" % current_vars_file)
1181     elif variant_dir in ext_build_dirs:
1182         # Things in ext are built without a variant directory.
1183         continue
1184     else:
1185         # Build dir-specific variables file doesn't exist.
1186
1187         # Make sure the directory is there so we can create it later
1188         opt_dir = dirname(current_vars_file)
1189         if not isdir(opt_dir):
1190             mkdir(opt_dir)
1191
1192         # Get default build variables from source tree.  Variables are
1193         # normally determined by name of $VARIANT_DIR, but can be
1194         # overridden by '--default=' arg on command line.
1195         default = GetOption('default')
1196         opts_dir = joinpath(main.root.abspath, 'build_opts')
1197         if default:
1198             default_vars_files = [joinpath(build_root, 'variables', default),
1199                                   joinpath(opts_dir, default)]
1200         else:
1201             default_vars_files = [joinpath(opts_dir, variant_dir)]
1202         existing_files = list(filter(isfile, default_vars_files))
1203         if existing_files:
1204             default_vars_file = existing_files[0]
1205             sticky_vars.files.append(default_vars_file)
1206             print("Variables file %s not found,\n  using defaults in %s"
1207                   % (current_vars_file, default_vars_file))
1208         else:
1209             error("Cannot find variables file %s or default file(s) %s"
1210                   % (current_vars_file, ' or '.join(default_vars_files)))
1211             Exit(1)
1212
1213     # Apply current variable settings to env
1214     sticky_vars.Update(env)
1215
1216     help_texts["local_vars"] += \
1217         "Build variables for %s:\n" % variant_dir \
1218                  + sticky_vars.GenerateHelpText(env)
1219
1220     # Process variable settings.
1221
1222     if not have_fenv and env['USE_FENV']:
1223         warning("<fenv.h> not available; forcing USE_FENV to False in",
1224                 variant_dir + ".")
1225         env['USE_FENV'] = False
1226
1227     if not env['USE_FENV']:
1228         warning("No IEEE FP rounding mode control in", variant_dir + ".\n"
1229                 "FP results may deviate slightly from other platforms.")
1230
1231     if not have_png and env['USE_PNG']:
1232         warning("<png.h> not available; forcing USE_PNG to False in",
1233                 variant_dir + ".")
1234         env['USE_PNG'] = False
1235
1236     if env['USE_PNG']:
1237         env.Append(LIBS=['png'])
1238
1239     if env['EFENCE']:
1240         env.Append(LIBS=['efence'])
1241
1242     if env['USE_KVM']:
1243         if not have_kvm:
1244             warning("Can not enable KVM, host seems to lack KVM support")
1245             env['USE_KVM'] = False
1246         elif not is_isa_kvm_compatible(env['TARGET_ISA']):
1247             print("Info: KVM support disabled due to unsupported host and "
1248                   "target ISA combination")
1249             env['USE_KVM'] = False
1250
1251     if env['USE_TUNTAP']:
1252         if not have_tuntap:
1253             warning("Can't connect EtherTap with a tap device.")
1254             env['USE_TUNTAP'] = False
1255
1256     if env['BUILD_GPU']:
1257         env.Append(CPPDEFINES=['BUILD_GPU'])
1258
1259     # Warn about missing optional functionality
1260     if env['USE_KVM']:
1261         if not main['HAVE_PERF_ATTR_EXCLUDE_HOST']:
1262             warning("perf_event headers lack support for the exclude_host "
1263                     "attribute. KVM instruction counts will be inaccurate.")
1264
1265     # Save sticky variable settings back to current variables file
1266     sticky_vars.Save(current_vars_file, env)
1267
1268     if env['USE_SSE2']:
1269         env.Append(CCFLAGS=['-msse2'])
1270
1271     env.Append(CCFLAGS='$CCFLAGS_EXTRA')
1272     env.Append(LINKFLAGS='$LDFLAGS_EXTRA')
1273
1274     # The src/SConscript file sets up the build rules in 'env' according
1275     # to the configured variables.  It returns a list of environments,
1276     # one for each variant build (debug, opt, etc.)
1277     SConscript('src/SConscript', variant_dir=variant_path,
1278                exports=['env', 'base_py_env'])
1279
1280 # base help text
1281 Help('''
1282 Usage: scons [scons options] [build variables] [target(s)]
1283
1284 Extra scons options:
1285 %(options)s
1286
1287 Global build variables:
1288 %(global_vars)s
1289
1290 %(local_vars)s
1291 ''' % help_texts)
1292
1293 atexit.register(summarize_warnings)