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
 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' ]),
 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     py_ld_flags = readCommand([python_config, '--ldflags'],
 687         exception='').split()
 688     py_libs = []
 689     for lib in py_ld_flags:
 690          if not lib.startswith('-l'):
 691              main.Append(LINKFLAGS=[lib])
 692          else:
 693              lib = lib[2:]
 694              if lib not in py_libs:
 695                  py_libs.append(lib)
 696
 697     # verify that this stuff works
 698     if not conf.CheckHeader('Python.h', '<>'):
 699         error("Check failed for Python.h header in",
 700                 ' '.join(py_includes), "\n"
 701               "Two possible reasons:\n"
 702               "1. Python headers are not installed (You can install the "
 703               "package python-dev on Ubuntu and RedHat)\n"
 704               "2. SCons is using a wrong C compiler. This can happen if "
 705               "CC has the wrong value.\n"
 706               "CC = %s" % main['CC'])
 707
 708     for lib in py_libs:
 709         if not conf.CheckLib(lib):
 710             error("Can't find library %s required by python." % lib)
 711
 712 main.Prepend(CPPPATH=Dir('ext/pybind11/include/'))
 713 # Bare minimum environment that only includes python
 714 base_py_env = main.Clone()
 715
 716 # On Solaris you need to use libsocket for socket ops
 717 if not conf.CheckLibWithHeader(None, 'sys/socket.h', 'C++', 'accept(0,0,0);'):
 718    if not conf.CheckLibWithHeader('socket', 'sys/socket.h',
 719                                   'C++', 'accept(0,0,0);'):
 720        error("Can't find library with socket calls (e.g. accept()).")
 721
 722 # Check for zlib.  If the check passes, libz will be automatically
 723 # added to the LIBS environment variable.
 724 if not conf.CheckLibWithHeader('z', 'zlib.h', 'C++','zlibVersion();'):
 725     error('Did not find needed zlib compression library '
 726           'and/or zlib.h header file.\n'
 727           'Please install zlib and try again.')
 728
 729 # If we have the protobuf compiler, also make sure we have the
 730 # development libraries. If the check passes, libprotobuf will be
 731 # automatically added to the LIBS environment variable. After
 732 # this, we can use the HAVE_PROTOBUF flag to determine if we have
 733 # got both protoc and libprotobuf available.
 734 main['HAVE_PROTOBUF'] = main['HAVE_PROTOC'] and \
 735     conf.CheckLibWithHeader('protobuf', 'google/protobuf/message.h',
 736                             'C++', 'GOOGLE_PROTOBUF_VERIFY_VERSION;')
 737
 738 # Valgrind gets much less confused if you tell it when you're using
 739 # alternative stacks.
 740 main['HAVE_VALGRIND'] = conf.CheckCHeader('valgrind/valgrind.h')
 741
 742 # If we have the compiler but not the library, print another warning.
 743 if main['HAVE_PROTOC'] and not main['HAVE_PROTOBUF']:
 744     warning('Did not find protocol buffer library and/or headers.\n'
 745             'Please install libprotobuf-dev for tracing support.')
 746
 747 # Check for librt.
 748 have_posix_clock = \
 749     conf.CheckLibWithHeader(None, 'time.h', 'C',
 750                             'clock_nanosleep(0,0,NULL,NULL);') or \
 751     conf.CheckLibWithHeader('rt', 'time.h', 'C',
 752                             'clock_nanosleep(0,0,NULL,NULL);')
 753
 754 have_posix_timers = \
 755     conf.CheckLibWithHeader([None, 'rt'], [ 'time.h', 'signal.h' ], 'C',
 756                             'timer_create(CLOCK_MONOTONIC, NULL, NULL);')
 757
 758 if not GetOption('without_tcmalloc'):
 759     if conf.CheckLib('tcmalloc'):
 760         main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
 761     elif conf.CheckLib('tcmalloc_minimal'):
 762         main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
 763     else:
 764         warning("You can get a 12% performance improvement by "
 765                 "installing tcmalloc (libgoogle-perftools-dev package "
 766                 "on Ubuntu or RedHat).")
 767
 768
 769 # Detect back trace implementations. The last implementation in the
 770 # list will be used by default.
 771 backtrace_impls = [ "none" ]
 772
 773 backtrace_checker = 'char temp;' + \
 774     ' backtrace_symbols_fd((void*)&temp, 0, 0);'
 775 if conf.CheckLibWithHeader(None, 'execinfo.h', 'C', backtrace_checker):
 776     backtrace_impls.append("glibc")
 777 elif conf.CheckLibWithHeader('execinfo', 'execinfo.h', 'C',
 778                              backtrace_checker):
 779     # NetBSD and FreeBSD need libexecinfo.
 780     backtrace_impls.append("glibc")
 781     main.Append(LIBS=['execinfo'])
 782
 783 if backtrace_impls[-1] == "none":
 784     default_backtrace_impl = "none"
 785     warning("No suitable back trace implementation found.")
 786
 787 if not have_posix_clock:
 788     warning("Can't find library for POSIX clocks.")
 789
 790 # Check for <fenv.h> (C99 FP environment control)
 791 have_fenv = conf.CheckHeader('fenv.h', '<>')
 792 if not have_fenv:
 793     warning("Header file <fenv.h> not found.\n"
 794             "This host has no IEEE FP rounding mode control.")
 795
 796 # Check for <png.h> (libpng library needed if wanting to dump
 797 # frame buffer image in png format)
 798 have_png = conf.CheckHeader('png.h', '<>')
 799 if not have_png:
 800     warning("Header file <png.h> not found.\n"
 801             "This host has no libpng library.\n"
 802             "Disabling support for PNG framebuffers.")
 803
 804 # Check if we should enable KVM-based hardware virtualization. The API
 805 # we rely on exists since version 2.6.36 of the kernel, but somehow
 806 # the KVM_API_VERSION does not reflect the change. We test for one of
 807 # the types as a fall back.
 808 have_kvm = conf.CheckHeader('linux/kvm.h', '<>')
 809 if not have_kvm:
 810     print("Info: Compatible header file <linux/kvm.h> not found, "
 811           "disabling KVM support.")
 812
 813 # Check if the TUN/TAP driver is available.
 814 have_tuntap = conf.CheckHeader('linux/if_tun.h', '<>')
 815 if not have_tuntap:
 816     print("Info: Compatible header file <linux/if_tun.h> not found.")
 817
 818 # x86 needs support for xsave. We test for the structure here since we
 819 # won't be able to run new tests by the time we know which ISA we're
 820 # targeting.
 821 have_kvm_xsave = conf.CheckTypeSize('struct kvm_xsave',
 822                                     '#include <linux/kvm.h>') != 0
 823
 824 # Check if the requested target ISA is compatible with the host
 825 def is_isa_kvm_compatible(isa):
 826     try:
 827         import platform
 828         host_isa = platform.machine()
 829     except:
 830         warning("Failed to determine host ISA.")
 831         return False
 832
 833     if not have_posix_timers:
 834         warning("Can not enable KVM, host seems to lack support "
 835                 "for POSIX timers")
 836         return False
 837
 838     if isa == "arm":
 839         return host_isa in ( "armv7l", "aarch64" )
 840     elif isa == "x86":
 841         if host_isa != "x86_64":
 842             return False
 843
 844         if not have_kvm_xsave:
 845             warning("KVM on x86 requires xsave support in kernel headers.")
 846             return False
 847
 848         return True
 849     else:
 850         return False
 851
 852
 853 # Check if the exclude_host attribute is available. We want this to
 854 # get accurate instruction counts in KVM.
 855 main['HAVE_PERF_ATTR_EXCLUDE_HOST'] = conf.CheckMember(
 856     'linux/perf_event.h', 'struct perf_event_attr', 'exclude_host')
 857
 858 def check_hdf5():
 859     return \
 860         conf.CheckLibWithHeader('hdf5', 'hdf5.h', 'C',
 861                                 'H5Fcreate("", 0, 0, 0);') and \
 862         conf.CheckLibWithHeader('hdf5_cpp', 'H5Cpp.h', 'C++',
 863                                 'H5::H5File("", 0);')
 864
 865 def check_hdf5_pkg(name):
 866     print("Checking for %s using pkg-config..." % name, end="")
 867     if not have_pkg_config:
 868         print(" pkg-config not found")
 869         return False
 870
 871     try:
 872         main.ParseConfig('pkg-config --cflags-only-I --libs-only-L %s' % name)
 873         print(" yes")
 874         return True
 875     except:
 876         print(" no")
 877         return False
 878
 879 # Check if there is a pkg-config configuration for hdf5. If we find
 880 # it, setup the environment to enable linking and header inclusion. We
 881 # don't actually try to include any headers or link with hdf5 at this
 882 # stage.
 883 if not check_hdf5_pkg('hdf5-serial'):
 884     check_hdf5_pkg('hdf5')
 885
 886 # Check if the HDF5 libraries can be found. This check respects the
 887 # include path and library path provided by pkg-config. We perform
 888 # this check even if there isn't a pkg-config configuration for hdf5
 889 # since some installations don't use pkg-config.
 890 have_hdf5 = check_hdf5()
 891 if not have_hdf5:
 892     print("Warning: Couldn't find any HDF5 C++ libraries. Disabling")
 893     print("         HDF5 support.")
 894
 895 ######################################################################
 896 #
 897 # Finish the configuration
 898 #
 899 main = conf.Finish()
 900
 901 ######################################################################
 902 #
 903 # Collect all non-global variables
 904 #
 905
 906 # Define the universe of supported ISAs
 907 all_isa_list = [ ]
 908 all_gpu_isa_list = [ ]
 909 Export('all_isa_list')
 910 Export('all_gpu_isa_list')
 911
 912 class CpuModel(object):
 913     '''The CpuModel class encapsulates everything the ISA parser needs to
 914     know about a particular CPU model.'''
 915
 916     # Dict of available CPU model objects.  Accessible as CpuModel.dict.
 917     dict = {}
 918
 919     # Constructor.  Automatically adds models to CpuModel.dict.
 920     def __init__(self, name, default=False):
 921         self.name = name           # name of model
 922
 923         # This cpu is enabled by default
 924         self.default = default
 925
 926         # Add self to dict
 927         if name in CpuModel.dict:
 928             raise AttributeError("CpuModel '%s' already registered" % name)
 929         CpuModel.dict[name] = self
 930
 931 Export('CpuModel')
 932
 933 # Sticky variables get saved in the variables file so they persist from
 934 # one invocation to the next (unless overridden, in which case the new
 935 # value becomes sticky).
 936 sticky_vars = Variables(args=ARGUMENTS)
 937 Export('sticky_vars')
 938
 939 # Sticky variables that should be exported
 940 export_vars = []
 941 Export('export_vars')
 942
 943 # For Ruby
 944 all_protocols = []
 945 Export('all_protocols')
 946 protocol_dirs = []
 947 Export('protocol_dirs')
 948 slicc_includes = []
 949 Export('slicc_includes')
 950
 951 # Walk the tree and execute all SConsopts scripts that wil add to the
 952 # above variables
 953 if GetOption('verbose'):
 954     print("Reading SConsopts")
 955 for bdir in [ base_dir ] + extras_dir_list:
 956     if not isdir(bdir):
 957         error("Directory '%s' does not exist." % bdir)
 958     for root, dirs, files in os.walk(bdir):
 959         if 'SConsopts' in files:
 960             if GetOption('verbose'):
 961                 print("Reading", joinpath(root, 'SConsopts'))
 962             SConscript(joinpath(root, 'SConsopts'))
 963
 964 all_isa_list.sort()
 965 all_gpu_isa_list.sort()
 966
 967 sticky_vars.AddVariables(
 968     EnumVariable('TARGET_ISA', 'Target ISA', 'alpha', all_isa_list),
 969     EnumVariable('TARGET_GPU_ISA', 'Target GPU ISA', 'hsail', all_gpu_isa_list),
 970     ListVariable('CPU_MODELS', 'CPU models',
 971                  sorted(n for n,m in CpuModel.dict.items() if m.default),
 972                  sorted(CpuModel.dict.keys())),
 973     BoolVariable('EFENCE', 'Link with Electric Fence malloc debugger',
 974                  False),
 975     BoolVariable('USE_SSE2',
 976                  'Compile for SSE2 (-msse2) to get IEEE FP on x86 hosts',
 977                  False),
 978     BoolVariable('USE_POSIX_CLOCK', 'Use POSIX Clocks', have_posix_clock),
 979     BoolVariable('USE_FENV', 'Use <fenv.h> IEEE mode control', have_fenv),
 980     BoolVariable('USE_PNG',  'Enable support for PNG images', have_png),
 981     BoolVariable('CP_ANNOTATE', 'Enable critical path annotation capability',
 982                  False),
 983     BoolVariable('USE_KVM', 'Enable hardware virtualized (KVM) CPU models',
 984                  have_kvm),
 985     BoolVariable('USE_TUNTAP',
 986                  'Enable using a tap device to bridge to the host network',
 987                  have_tuntap),
 988     BoolVariable('BUILD_GPU', 'Build the compute-GPU model', False),
 989     EnumVariable('PROTOCOL', 'Coherence protocol for Ruby', 'None',
 990                   all_protocols),
 991     EnumVariable('BACKTRACE_IMPL', 'Post-mortem dump implementation',
 992                  backtrace_impls[-1], backtrace_impls),
 993     ('NUMBER_BITS_PER_SET', 'Max elements in set (default 64)',
 994                  64),
 995     BoolVariable('USE_HDF5', 'Enable the HDF5 support', have_hdf5),
 996     )
 997
 998 # These variables get exported to #defines in config/*.hh (see src/SConscript).
 999 export_vars += ['USE_FENV', 'TARGET_ISA', 'TARGET_GPU_ISA', 'CP_ANNOTATE',
1000                 'USE_POSIX_CLOCK', 'USE_KVM', 'USE_TUNTAP', 'PROTOCOL',
1001                 'HAVE_PROTOBUF', 'HAVE_VALGRIND',
1002                 'HAVE_PERF_ATTR_EXCLUDE_HOST', 'USE_PNG',
1003                 'NUMBER_BITS_PER_SET', 'USE_HDF5']
1004
1005 ###################################################
1006 #
1007 # Define a SCons builder for configuration flag headers.
1008 #
1009 ###################################################
1010
1011 # This function generates a config header file that #defines the
1012 # variable symbol to the current variable setting (0 or 1).  The source
1013 # operands are the name of the variable and a Value node containing the
1014 # value of the variable.
1015 def build_config_file(target, source, env):
1016     (variable, value) = [s.get_contents().decode('utf-8') for s in source]
1017     with open(str(target[0]), 'w') as f:
1018         print('#define', variable, value, file=f)
1019     return None
1020
1021 # Combine the two functions into a scons Action object.
1022 config_action = MakeAction(build_config_file, Transform("CONFIG H", 2))
1023
1024 # The emitter munges the source & target node lists to reflect what
1025 # we're really doing.
1026 def config_emitter(target, source, env):
1027     # extract variable name from Builder arg
1028     variable = str(target[0])
1029     # True target is config header file
1030     target = joinpath('config', variable.lower() + '.hh')
1031     val = env[variable]
1032     if isinstance(val, bool):
1033         # Force value to 0/1
1034         val = int(val)
1035     elif isinstance(val, str):
1036         val = '"' + val + '"'
1037
1038     # Sources are variable name & value (packaged in SCons Value nodes)
1039     return ([target], [Value(variable), Value(val)])
1040
1041 config_builder = Builder(emitter = config_emitter, action = config_action)
1042
1043 main.Append(BUILDERS = { 'ConfigFile' : config_builder })
1044
1045 ###################################################
1046 #
1047 # Builders for static and shared partially linked object files.
1048 #
1049 ###################################################
1050
1051 partial_static_builder = Builder(action=SCons.Defaults.LinkAction,
1052                                  src_suffix='$OBJSUFFIX',
1053                                  src_builder=['StaticObject', 'Object'],
1054                                  LINKFLAGS='$PLINKFLAGS',
1055                                  LIBS='')
1056
1057 def partial_shared_emitter(target, source, env):
1058     for tgt in target:
1059         tgt.attributes.shared = 1
1060     return (target, source)
1061 partial_shared_builder = Builder(action=SCons.Defaults.ShLinkAction,
1062                                  emitter=partial_shared_emitter,
1063                                  src_suffix='$SHOBJSUFFIX',
1064                                  src_builder='SharedObject',
1065                                  SHLINKFLAGS='$PSHLINKFLAGS',
1066                                  LIBS='')
1067
1068 main.Append(BUILDERS = { 'PartialShared' : partial_shared_builder,
1069                          'PartialStatic' : partial_static_builder })
1070
1071 def add_local_rpath(env, *targets):
1072     '''Set up an RPATH for a library which lives in the build directory.
1073
1074     The construction environment variable BIN_RPATH_PREFIX should be set to
1075     the relative path of the build directory starting from the location of the
1076     binary.'''
1077     for target in targets:
1078         target = env.Entry(target)
1079         if not isinstance(target, SCons.Node.FS.Dir):
1080             target = target.dir
1081         relpath = os.path.relpath(target.abspath, env['BUILDDIR'])
1082         components = [
1083             '\\$$ORIGIN',
1084             '${BIN_RPATH_PREFIX}',
1085             relpath
1086         ]
1087         env.Append(RPATH=[env.Literal(os.path.join(*components))])
1088
1089 if sys.platform != "darwin":
1090     main.Append(LINKFLAGS=Split('-z origin'))
1091
1092 main.AddMethod(add_local_rpath, 'AddLocalRPATH')
1093
1094 # builds in ext are shared across all configs in the build root.
1095 ext_dir = abspath(joinpath(str(main.root), 'ext'))
1096 ext_build_dirs = []
1097 for root, dirs, files in os.walk(ext_dir):
1098     if 'SConscript' in files:
1099         build_dir = os.path.relpath(root, ext_dir)
1100         ext_build_dirs.append(build_dir)
1101         main.SConscript(joinpath(root, 'SConscript'),
1102                         variant_dir=joinpath(build_root, build_dir))
1103
1104 gdb_xml_dir = joinpath(ext_dir, 'gdb-xml')
1105 Export('gdb_xml_dir')
1106
1107 ###################################################
1108 #
1109 # This builder and wrapper method are used to set up a directory with
1110 # switching headers. Those are headers which are in a generic location and
1111 # that include more specific headers from a directory chosen at build time
1112 # based on the current build settings.
1113 #
1114 ###################################################
1115
1116 def build_switching_header(target, source, env):
1117     path = str(target[0])
1118     subdir = str(source[0])
1119     dp, fp = os.path.split(path)
1120     dp = os.path.relpath(os.path.realpath(dp),
1121                          os.path.realpath(env['BUILDDIR']))
1122     with open(path, 'w') as hdr:
1123         print('#include "%s/%s/%s"' % (dp, subdir, fp), file=hdr)
1124
1125 switching_header_action = MakeAction(build_switching_header,
1126                                      Transform('GENERATE'))
1127
1128 switching_header_builder = Builder(action=switching_header_action,
1129                                    source_factory=Value,
1130                                    single_source=True)
1131
1132 main.Append(BUILDERS = { 'SwitchingHeader': switching_header_builder })
1133
1134 def switching_headers(self, headers, source):
1135     for header in headers:
1136         self.SwitchingHeader(header, source)
1137
1138 main.AddMethod(switching_headers, 'SwitchingHeaders')
1139
1140 ###################################################
1141 #
1142 # Define build environments for selected configurations.
1143 #
1144 ###################################################
1145
1146 for variant_path in variant_paths:
1147     if not GetOption('silent'):
1148         print("Building in", variant_path)
1149
1150     # Make a copy of the build-root environment to use for this config.
1151     env = main.Clone()
1152     env['BUILDDIR'] = variant_path
1153
1154     # variant_dir is the tail component of build path, and is used to
1155     # determine the build parameters (e.g., 'X86')
1156     (build_root, variant_dir) = splitpath(variant_path)
1157
1158     # Set env variables according to the build directory config.
1159     sticky_vars.files = []
1160     # Variables for $BUILD_ROOT/$VARIANT_DIR are stored in
1161     # $BUILD_ROOT/variables/$VARIANT_DIR so you can nuke
1162     # $BUILD_ROOT/$VARIANT_DIR without losing your variables settings.
1163     current_vars_file = joinpath(build_root, 'variables', variant_dir)
1164     if isfile(current_vars_file):
1165         sticky_vars.files.append(current_vars_file)
1166         if not GetOption('silent'):
1167             print("Using saved variables file %s" % current_vars_file)
1168     elif variant_dir in ext_build_dirs:
1169         # Things in ext are built without a variant directory.
1170         continue
1171     else:
1172         # Build dir-specific variables file doesn't exist.
1173
1174         # Make sure the directory is there so we can create it later
1175         opt_dir = dirname(current_vars_file)
1176         if not isdir(opt_dir):
1177             mkdir(opt_dir)
1178
1179         # Get default build variables from source tree.  Variables are
1180         # normally determined by name of $VARIANT_DIR, but can be
1181         # overridden by '--default=' arg on command line.
1182         default = GetOption('default')
1183         opts_dir = joinpath(main.root.abspath, 'build_opts')
1184         if default:
1185             default_vars_files = [joinpath(build_root, 'variables', default),
1186                                   joinpath(opts_dir, default)]
1187         else:
1188             default_vars_files = [joinpath(opts_dir, variant_dir)]
1189         existing_files = list(filter(isfile, default_vars_files))
1190         if existing_files:
1191             default_vars_file = existing_files[0]
1192             sticky_vars.files.append(default_vars_file)
1193             print("Variables file %s not found,\n  using defaults in %s"
1194                   % (current_vars_file, default_vars_file))
1195         else:
1196             error("Cannot find variables file %s or default file(s) %s"
1197                   % (current_vars_file, ' or '.join(default_vars_files)))
1198             Exit(1)
1199
1200     # Apply current variable settings to env
1201     sticky_vars.Update(env)
1202
1203     help_texts["local_vars"] += \
1204         "Build variables for %s:\n" % variant_dir \
1205                  + sticky_vars.GenerateHelpText(env)
1206
1207     # Process variable settings.
1208
1209     if not have_fenv and env['USE_FENV']:
1210         warning("<fenv.h> not available; forcing USE_FENV to False in",
1211                 variant_dir + ".")
1212         env['USE_FENV'] = False
1213
1214     if not env['USE_FENV']:
1215         warning("No IEEE FP rounding mode control in", variant_dir + ".\n"
1216                 "FP results may deviate slightly from other platforms.")
1217
1218     if not have_png and env['USE_PNG']:
1219         warning("<png.h> not available; forcing USE_PNG to False in",
1220                 variant_dir + ".")
1221         env['USE_PNG'] = False
1222
1223     if env['USE_PNG']:
1224         env.Append(LIBS=['png'])
1225
1226     if env['EFENCE']:
1227         env.Append(LIBS=['efence'])
1228
1229     if env['USE_KVM']:
1230         if not have_kvm:
1231             warning("Can not enable KVM, host seems to lack KVM support")
1232             env['USE_KVM'] = False
1233         elif not is_isa_kvm_compatible(env['TARGET_ISA']):
1234             print("Info: KVM support disabled due to unsupported host and "
1235                   "target ISA combination")
1236             env['USE_KVM'] = False
1237
1238     if env['USE_TUNTAP']:
1239         if not have_tuntap:
1240             warning("Can't connect EtherTap with a tap device.")
1241             env['USE_TUNTAP'] = False
1242
1243     if env['BUILD_GPU']:
1244         env.Append(CPPDEFINES=['BUILD_GPU'])
1245
1246     # Warn about missing optional functionality
1247     if env['USE_KVM']:
1248         if not main['HAVE_PERF_ATTR_EXCLUDE_HOST']:
1249             warning("perf_event headers lack support for the exclude_host "
1250                     "attribute. KVM instruction counts will be inaccurate.")
1251
1252     # Save sticky variable settings back to current variables file
1253     sticky_vars.Save(current_vars_file, env)
1254
1255     if env['USE_SSE2']:
1256         env.Append(CCFLAGS=['-msse2'])
1257
1258     env.Append(CCFLAGS='$CCFLAGS_EXTRA')
1259     env.Append(LINKFLAGS='$LDFLAGS_EXTRA')
1260
1261     # The src/SConscript file sets up the build rules in 'env' according
1262     # to the configured variables.  It returns a list of environments,
1263     # one for each variant build (debug, opt, etc.)
1264     SConscript('src/SConscript', variant_dir=variant_path,
1265                exports=['env', 'base_py_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)
1279
1280 atexit.register(summarize_warnings)