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 # Authors: Steve Reinhardt
  44 #          Nathan Binkert
  45
  46 ###################################################
  47 #
  48 # SCons top-level build description (SConstruct) file.
  49 #
  50 # While in this directory ('gem5'), just type 'scons' to build the default
  51 # configuration (see below), or type 'scons build/<CONFIG>/<binary>'
  52 # to build some other configuration (e.g., 'build/ALPHA/gem5.opt' for
  53 # the optimized full-system version).
  54 #
  55 # You can build gem5 in a different directory as long as there is a
  56 # 'build/<CONFIG>' somewhere along the target path.  The build system
  57 # expects that all configs under the same build directory are being
  58 # built for the same host system.
  59 #
  60 # Examples:
  61 #
  62 #   The following two commands are equivalent.  The '-u' option tells
  63 #   scons to search up the directory tree for this SConstruct file.
  64 #   % cd <path-to-src>/gem5 ; scons build/ALPHA/gem5.debug
  65 #   % cd <path-to-src>/gem5/build/ALPHA; scons -u gem5.debug
  66 #
  67 #   The following two commands are equivalent and demonstrate building
  68 #   in a directory outside of the source tree.  The '-C' option tells
  69 #   scons to chdir to the specified directory to find this SConstruct
  70 #   file.
  71 #   % cd <path-to-src>/gem5 ; scons /local/foo/build/ALPHA/gem5.debug
  72 #   % cd /local/foo/build/ALPHA; scons -C <path-to-src>/gem5 gem5.debug
  73 #
  74 # You can use 'scons -H' to print scons options.  If you're in this
  75 # 'gem5' directory (or use -u or -C to tell scons where to find this
  76 # file), you can use 'scons -h' to print all the gem5-specific build
  77 # options as well.
  78 #
  79 ###################################################
  80
  81 from __future__ import print_function
  82
  83 # Global Python includes
  84 import itertools
  85 import os
  86 import re
  87 import shutil
  88 import subprocess
  89 import sys
  90
  91 from os import mkdir, environ
  92 from os.path import abspath, basename, dirname, expanduser, normpath
  93 from os.path import exists,  isdir, isfile
  94 from os.path import join as joinpath, split as splitpath
  95 from re import match
  96
  97 # SCons includes
  98 import SCons
  99 import SCons.Node
 100 import SCons.Node.FS
 101
 102 from m5.util import compareVersions, readCommand
 103
 104 help_texts = {
 105     "options" : "",
 106     "global_vars" : "",
 107     "local_vars" : ""
 108 }
 109
 110 Export("help_texts")
 111
 112
 113 # There's a bug in scons in that (1) by default, the help texts from
 114 # AddOption() are supposed to be displayed when you type 'scons -h'
 115 # and (2) you can override the help displayed by 'scons -h' using the
 116 # Help() function, but these two features are incompatible: once
 117 # you've overridden the help text using Help(), there's no way to get
 118 # at the help texts from AddOptions.  See:
 119 #     http://scons.tigris.org/issues/show_bug.cgi?id=2356
 120 #     http://scons.tigris.org/issues/show_bug.cgi?id=2611
 121 # This hack lets us extract the help text from AddOptions and
 122 # re-inject it via Help().  Ideally someday this bug will be fixed and
 123 # we can just use AddOption directly.
 124 def AddLocalOption(*args, **kwargs):
 125     col_width = 30
 126
 127     help = "  " + ", ".join(args)
 128     if "help" in kwargs:
 129         length = len(help)
 130         if length >= col_width:
 131             help += "\n" + " " * col_width
 132         else:
 133             help += " " * (col_width - length)
 134         help += kwargs["help"]
 135     help_texts["options"] += help + "\n"
 136
 137     AddOption(*args, **kwargs)
 138
 139 AddLocalOption('--colors', dest='use_colors', action='store_true',
 140                help="Add color to abbreviated scons output")
 141 AddLocalOption('--no-colors', dest='use_colors', action='store_false',
 142                help="Don't add color to abbreviated scons output")
 143 AddLocalOption('--with-cxx-config', dest='with_cxx_config',
 144                action='store_true',
 145                help="Build with support for C++-based configuration")
 146 AddLocalOption('--default', dest='default', type='string', action='store',
 147                help='Override which build_opts file to use for defaults')
 148 AddLocalOption('--ignore-style', dest='ignore_style', action='store_true',
 149                help='Disable style checking hooks')
 150 AddLocalOption('--gold-linker', dest='gold_linker', action='store_true',
 151                help='Use the gold linker')
 152 AddLocalOption('--no-lto', dest='no_lto', action='store_true',
 153                help='Disable Link-Time Optimization for fast')
 154 AddLocalOption('--force-lto', dest='force_lto', action='store_true',
 155                help='Use Link-Time Optimization instead of partial linking' +
 156                     ' when the compiler doesn\'t support using them together.')
 157 AddLocalOption('--update-ref', dest='update_ref', action='store_true',
 158                help='Update test reference outputs')
 159 AddLocalOption('--verbose', dest='verbose', action='store_true',
 160                help='Print full tool command lines')
 161 AddLocalOption('--without-python', dest='without_python',
 162                action='store_true',
 163                help='Build without Python configuration support')
 164 AddLocalOption('--without-tcmalloc', dest='without_tcmalloc',
 165                action='store_true',
 166                help='Disable linking against tcmalloc')
 167 AddLocalOption('--with-ubsan', dest='with_ubsan', action='store_true',
 168                help='Build with Undefined Behavior Sanitizer if available')
 169 AddLocalOption('--with-asan', dest='with_asan', action='store_true',
 170                help='Build with Address Sanitizer if available')
 171
 172 from gem5_scons import Transform, error, warning
 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/ALPHA/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 def find_first_prog(prog_names):
 219     """Find the absolute path to the first existing binary in prog_names"""
 220
 221     if not isinstance(prog_names, (list, tuple)):
 222         prog_names = [ prog_names ]
 223
 224     for p in prog_names:
 225         p = main.WhereIs(p)
 226         if p is not None:
 227             return p
 228
 229     return None
 230
 231 # Each target must have 'build' in the interior of the path; the
 232 # directory below this will determine the build parameters.  For
 233 # example, for target 'foo/bar/build/ALPHA_SE/arch/alpha/blah.do' we
 234 # recognize that ALPHA_SE specifies the configuration because it
 235 # follow 'build' in the build path.
 236
 237 # The funky assignment to "[:]" is needed to replace the list contents
 238 # in place rather than reassign the symbol to a new list, which
 239 # doesn't work (obviously!).
 240 BUILD_TARGETS[:] = makePathListAbsolute(BUILD_TARGETS)
 241
 242 # Generate a list of the unique build roots and configs that the
 243 # collected targets reference.
 244 variant_paths = []
 245 build_root = None
 246 for t in BUILD_TARGETS:
 247     path_dirs = t.split('/')
 248     try:
 249         build_top = rfind(path_dirs, 'build', -2)
 250     except:
 251         error("No non-leaf 'build' dir found on target path.", t)
 252     this_build_root = joinpath('/',*path_dirs[:build_top+1])
 253     if not build_root:
 254         build_root = this_build_root
 255     else:
 256         if this_build_root != build_root:
 257             error("build targets not under same build root\n"
 258                   "  %s\n  %s" % (build_root, this_build_root))
 259     variant_path = joinpath('/',*path_dirs[:build_top+2])
 260     if variant_path not in variant_paths:
 261         variant_paths.append(variant_path)
 262
 263 # Make sure build_root exists (might not if this is the first build there)
 264 if not isdir(build_root):
 265     mkdir(build_root)
 266 main['BUILDROOT'] = build_root
 267
 268 Export('main')
 269
 270 main.SConsignFile(joinpath(build_root, "sconsign"))
 271
 272 # Default duplicate option is to use hard links, but this messes up
 273 # when you use emacs to edit a file in the target dir, as emacs moves
 274 # file to file~ then copies to file, breaking the link.  Symbolic
 275 # (soft) links work better.
 276 main.SetOption('duplicate', 'soft-copy')
 277
 278 #
 279 # Set up global sticky variables... these are common to an entire build
 280 # tree (not specific to a particular build like ALPHA_SE)
 281 #
 282
 283 global_vars_file = joinpath(build_root, 'variables.global')
 284
 285 global_vars = Variables(global_vars_file, args=ARGUMENTS)
 286
 287 global_vars.AddVariables(
 288     ('CC', 'C compiler', environ.get('CC', main['CC'])),
 289     ('CXX', 'C++ compiler', environ.get('CXX', main['CXX'])),
 290     ('CCFLAGS_EXTRA', 'Extra C and C++ compiler flags', ''),
 291     ('LDFLAGS_EXTRA', 'Extra linker flags', ''),
 292     ('PYTHON_CONFIG', 'Python config binary to use',
 293      [ 'python2.7-config', 'python-config' ]),
 294     ('PROTOC', 'protoc tool', environ.get('PROTOC', 'protoc')),
 295     ('BATCH', 'Use batch pool for build and tests', False),
 296     ('BATCH_CMD', 'Batch pool submission command name', 'qdo'),
 297     ('M5_BUILD_CACHE', 'Cache built objects in this directory', False),
 298     ('EXTRAS', 'Add extra directories to the compilation', '')
 299     )
 300
 301 # Update main environment with values from ARGUMENTS & global_vars_file
 302 global_vars.Update(main)
 303 help_texts["global_vars"] += global_vars.GenerateHelpText(main)
 304
 305 # Save sticky variable settings back to current variables file
 306 global_vars.Save(global_vars_file, main)
 307
 308 # Parse EXTRAS variable to build list of all directories where we're
 309 # look for sources etc.  This list is exported as extras_dir_list.
 310 base_dir = main.srcdir.abspath
 311 if main['EXTRAS']:
 312     extras_dir_list = makePathListAbsolute(main['EXTRAS'].split(':'))
 313 else:
 314     extras_dir_list = []
 315
 316 Export('base_dir')
 317 Export('extras_dir_list')
 318
 319 # the ext directory should be on the #includes path
 320 main.Append(CPPPATH=[Dir('ext')])
 321
 322 # Add shared top-level headers
 323 main.Prepend(CPPPATH=Dir('include'))
 324
 325 if GetOption('verbose'):
 326     def MakeAction(action, string, *args, **kwargs):
 327         return Action(action, *args, **kwargs)
 328 else:
 329     MakeAction = Action
 330     main['CCCOMSTR']        = Transform("CC")
 331     main['CXXCOMSTR']       = Transform("CXX")
 332     main['ASCOMSTR']        = Transform("AS")
 333     main['ARCOMSTR']        = Transform("AR", 0)
 334     main['LINKCOMSTR']      = Transform("LINK", 0)
 335     main['SHLINKCOMSTR']    = Transform("SHLINK", 0)
 336     main['RANLIBCOMSTR']    = Transform("RANLIB", 0)
 337     main['M4COMSTR']        = Transform("M4")
 338     main['SHCCCOMSTR']      = Transform("SHCC")
 339     main['SHCXXCOMSTR']     = Transform("SHCXX")
 340 Export('MakeAction')
 341
 342 # Initialize the Link-Time Optimization (LTO) flags
 343 main['LTO_CCFLAGS'] = []
 344 main['LTO_LDFLAGS'] = []
 345
 346 # According to the readme, tcmalloc works best if the compiler doesn't
 347 # assume that we're using the builtin malloc and friends. These flags
 348 # are compiler-specific, so we need to set them after we detect which
 349 # compiler we're using.
 350 main['TCMALLOC_CCFLAGS'] = []
 351
 352 CXX_version = readCommand([main['CXX'],'--version'], exception=False)
 353 CXX_V = readCommand([main['CXX'],'-V'], exception=False)
 354
 355 main['GCC'] = CXX_version and CXX_version.find('g++') >= 0
 356 main['CLANG'] = CXX_version and CXX_version.find('clang') >= 0
 357 if main['GCC'] + main['CLANG'] > 1:
 358     error('Two compilers enabled at once?')
 359
 360 # Set up default C++ compiler flags
 361 if main['GCC'] or main['CLANG']:
 362     # As gcc and clang share many flags, do the common parts here
 363     main.Append(CCFLAGS=['-pipe'])
 364     main.Append(CCFLAGS=['-fno-strict-aliasing'])
 365     # Enable -Wall and -Wextra and then disable the few warnings that
 366     # we consistently violate
 367     main.Append(CCFLAGS=['-Wall', '-Wundef', '-Wextra',
 368                          '-Wno-sign-compare', '-Wno-unused-parameter'])
 369     # We always compile using C++11
 370     main.Append(CXXFLAGS=['-std=c++11'])
 371     if sys.platform.startswith('freebsd'):
 372         main.Append(CCFLAGS=['-I/usr/local/include'])
 373         main.Append(CXXFLAGS=['-I/usr/local/include'])
 374
 375     main.Append(LINKFLAGS='-Wl,--as-needed')
 376     main['FILTER_PSHLINKFLAGS'] = lambda x: str(x).replace(' -shared', '')
 377     main['PSHLINKFLAGS'] = main.subst('${FILTER_PSHLINKFLAGS(SHLINKFLAGS)}')
 378     if GetOption('gold_linker'):
 379         main.Append(LINKFLAGS='-fuse-ld=gold')
 380     main['PLINKFLAGS'] = main.get('LINKFLAGS')
 381     shared_partial_flags = ['-r', '-nostdlib']
 382     main.Append(PSHLINKFLAGS=shared_partial_flags)
 383     main.Append(PLINKFLAGS=shared_partial_flags)
 384
 385     # Treat warnings as errors but white list some warnings that we
 386     # want to allow (e.g., deprecation warnings).
 387     main.Append(CCFLAGS=['-Werror',
 388                          '-Wno-error=deprecated-declarations',
 389                          '-Wno-error=deprecated',
 390                         ])
 391 else:
 392     error('\n'.join((
 393           "Don't know what compiler options to use for your compiler.",
 394           "compiler: " + main['CXX'],
 395           "version: " + CXX_version.replace('\n', '<nl>') if
 396                 CXX_version else 'COMMAND NOT FOUND!',
 397           "If you're trying to use a compiler other than GCC",
 398           "or clang, there appears to be something wrong with your",
 399           "environment.",
 400           "",
 401           "If you are trying to use a compiler other than those listed",
 402           "above you will need to ease fix SConstruct and ",
 403           "src/SConscript to support that compiler.")))
 404
 405 if main['GCC']:
 406     # Check for a supported version of gcc. >= 4.8 is chosen for its
 407     # level of c++11 support. See
 408     # http://gcc.gnu.org/projects/cxx0x.html for details.
 409     gcc_version = readCommand([main['CXX'], '-dumpversion'], exception=False)
 410     if compareVersions(gcc_version, "4.8") < 0:
 411         error('gcc version 4.8 or newer required.\n'
 412               'Installed version:', gcc_version)
 413         Exit(1)
 414
 415     main['GCC_VERSION'] = gcc_version
 416
 417     if compareVersions(gcc_version, '4.9') >= 0:
 418         # Incremental linking with LTO is currently broken in gcc versions
 419         # 4.9 and above. A version where everything works completely hasn't
 420         # yet been identified.
 421         #
 422         # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67548
 423         main['BROKEN_INCREMENTAL_LTO'] = True
 424     if compareVersions(gcc_version, '6.0') >= 0:
 425         # gcc versions 6.0 and greater accept an -flinker-output flag which
 426         # selects what type of output the linker should generate. This is
 427         # necessary for incremental lto to work, but is also broken in
 428         # current versions of gcc. It may not be necessary in future
 429         # versions. We add it here since it might be, and as a reminder that
 430         # it exists. It's excluded if lto is being forced.
 431         #
 432         # https://gcc.gnu.org/gcc-6/changes.html
 433         # https://gcc.gnu.org/ml/gcc-patches/2015-11/msg03161.html
 434         # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69866
 435         if not GetOption('force_lto'):
 436             main.Append(PSHLINKFLAGS='-flinker-output=rel')
 437             main.Append(PLINKFLAGS='-flinker-output=rel')
 438
 439     disable_lto = GetOption('no_lto')
 440     if not disable_lto and main.get('BROKEN_INCREMENTAL_LTO', False) and \
 441             not GetOption('force_lto'):
 442         warning('Warning: Your compiler doesn\'t support incremental linking '
 443                 'and lto at the same time, so lto is being disabled. To force '
 444                 'lto on anyway, use the --force-lto option. That will disable '
 445                 'partial linking.')
 446         disable_lto = True
 447
 448     # Add the appropriate Link-Time Optimization (LTO) flags
 449     # unless LTO is explicitly turned off. Note that these flags
 450     # are only used by the fast target.
 451     if not disable_lto:
 452         # Pass the LTO flag when compiling to produce GIMPLE
 453         # output, we merely create the flags here and only append
 454         # them later
 455         main['LTO_CCFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
 456
 457         # Use the same amount of jobs for LTO as we are running
 458         # scons with
 459         main['LTO_LDFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
 460
 461     main.Append(TCMALLOC_CCFLAGS=['-fno-builtin-malloc', '-fno-builtin-calloc',
 462                                   '-fno-builtin-realloc', '-fno-builtin-free'])
 463
 464 elif main['CLANG']:
 465     # Check for a supported version of clang, >= 3.1 is needed to
 466     # support similar features as gcc 4.8. See
 467     # http://clang.llvm.org/cxx_status.html for details
 468     clang_version_re = re.compile(".* version (\d+\.\d+)")
 469     clang_version_match = clang_version_re.search(CXX_version)
 470     if (clang_version_match):
 471         clang_version = clang_version_match.groups()[0]
 472         if compareVersions(clang_version, "3.1") < 0:
 473             error('clang version 3.1 or newer required.\n'
 474                   'Installed version:', clang_version)
 475     else:
 476         error('Unable to determine clang version.')
 477
 478     # clang has a few additional warnings that we disable, extraneous
 479     # parantheses are allowed due to Ruby's printing of the AST,
 480     # finally self assignments are allowed as the generated CPU code
 481     # is relying on this
 482     main.Append(CCFLAGS=['-Wno-parentheses',
 483                          '-Wno-self-assign',
 484                          # Some versions of libstdc++ (4.8?) seem to
 485                          # use struct hash and class hash
 486                          # interchangeably.
 487                          '-Wno-mismatched-tags',
 488                          ])
 489
 490     main.Append(TCMALLOC_CCFLAGS=['-fno-builtin'])
 491
 492     # On Mac OS X/Darwin we need to also use libc++ (part of XCode) as
 493     # opposed to libstdc++, as the later is dated.
 494     if sys.platform == "darwin":
 495         main.Append(CXXFLAGS=['-stdlib=libc++'])
 496         main.Append(LIBS=['c++'])
 497
 498     # On FreeBSD we need libthr.
 499     if sys.platform.startswith('freebsd'):
 500         main.Append(LIBS=['thr'])
 501
 502 # Add sanitizers flags
 503 sanitizers=[]
 504 if GetOption('with_ubsan'):
 505     # Only gcc >= 4.9 supports UBSan, so check both the version
 506     # and the command-line option before adding the compiler and
 507     # linker flags.
 508     if not main['GCC'] or compareVersions(main['GCC_VERSION'], '4.9') >= 0:
 509         sanitizers.append('undefined')
 510 if GetOption('with_asan'):
 511     # Available for gcc >= 4.8 or llvm >= 3.1 both a requirement
 512     # by the build system
 513     sanitizers.append('address')
 514 if sanitizers:
 515     sanitizers = ','.join(sanitizers)
 516     if main['GCC'] or main['CLANG']:
 517         main.Append(CCFLAGS=['-fsanitize=%s' % sanitizers,
 518                              '-fno-omit-frame-pointer'],
 519                     LINKFLAGS='-fsanitize=%s' % sanitizers)
 520     else:
 521         warning("Don't know how to enable %s sanitizer(s) for your "
 522                 "compiler." % sanitizers)
 523
 524 # Set up common yacc/bison flags (needed for Ruby)
 525 main['YACCFLAGS'] = '-d'
 526 main['YACCHXXFILESUFFIX'] = '.hh'
 527
 528 # Do this after we save setting back, or else we'll tack on an
 529 # extra 'qdo' every time we run scons.
 530 if main['BATCH']:
 531     main['CC']     = main['BATCH_CMD'] + ' ' + main['CC']
 532     main['CXX']    = main['BATCH_CMD'] + ' ' + main['CXX']
 533     main['AS']     = main['BATCH_CMD'] + ' ' + main['AS']
 534     main['AR']     = main['BATCH_CMD'] + ' ' + main['AR']
 535     main['RANLIB'] = main['BATCH_CMD'] + ' ' + main['RANLIB']
 536
 537 if sys.platform == 'cygwin':
 538     # cygwin has some header file issues...
 539     main.Append(CCFLAGS=["-Wno-uninitialized"])
 540
 541
 542 have_pkg_config = readCommand(['pkg-config', '--version'], exception='')
 543
 544 # Check for the protobuf compiler
 545 try:
 546     main['HAVE_PROTOC'] = True
 547     protoc_version = readCommand([main['PROTOC'], '--version']).split()
 548
 549     # First two words should be "libprotoc x.y.z"
 550     if len(protoc_version) < 2 or protoc_version[0] != 'libprotoc':
 551         warning('Protocol buffer compiler (protoc) not found.\n'
 552                 'Please install protobuf-compiler for tracing support.')
 553         main['HAVE_PROTOC'] = False
 554     else:
 555         # Based on the availability of the compress stream wrappers,
 556         # require 2.1.0
 557         min_protoc_version = '2.1.0'
 558         if compareVersions(protoc_version[1], min_protoc_version) < 0:
 559             warning('protoc version', min_protoc_version,
 560                     'or newer required.\n'
 561                     'Installed version:', protoc_version[1])
 562             main['HAVE_PROTOC'] = False
 563         else:
 564             # Attempt to determine the appropriate include path and
 565             # library path using pkg-config, that means we also need to
 566             # check for pkg-config. Note that it is possible to use
 567             # protobuf without the involvement of pkg-config. Later on we
 568             # check go a library config check and at that point the test
 569             # will fail if libprotobuf cannot be found.
 570             if have_pkg_config:
 571                 try:
 572                     # Attempt to establish what linking flags to add for
 573                     # protobuf
 574                     # using pkg-config
 575                     main.ParseConfig(
 576                             'pkg-config --cflags --libs-only-L protobuf')
 577                 except:
 578                     warning('pkg-config could not get protobuf flags.')
 579 except Exception as e:
 580     warning('While checking protoc version:', str(e))
 581     main['HAVE_PROTOC'] = False
 582
 583 # Check for 'timeout' from GNU coreutils. If present, regressions will
 584 # be run with a time limit. We require version 8.13 since we rely on
 585 # support for the '--foreground' option.
 586 if sys.platform.startswith('freebsd'):
 587     timeout_lines = readCommand(['gtimeout', '--version'],
 588                                 exception='').splitlines()
 589 else:
 590     timeout_lines = readCommand(['timeout', '--version'],
 591                                 exception='').splitlines()
 592 # Get the first line and tokenize it
 593 timeout_version = timeout_lines[0].split() if timeout_lines else []
 594 main['TIMEOUT'] =  timeout_version and \
 595     compareVersions(timeout_version[-1], '8.13') >= 0
 596
 597 # Add a custom Check function to test for structure members.
 598 def CheckMember(context, include, decl, member, include_quotes="<>"):
 599     context.Message("Checking for member %s in %s..." %
 600                     (member, decl))
 601     text = """
 602 #include %(header)s
 603 int main(){
 604   %(decl)s test;
 605   (void)test.%(member)s;
 606   return 0;
 607 };
 608 """ % { "header" : include_quotes[0] + include + include_quotes[1],
 609         "decl" : decl,
 610         "member" : member,
 611         }
 612
 613     ret = context.TryCompile(text, extension=".cc")
 614     context.Result(ret)
 615     return ret
 616
 617 # Platform-specific configuration.  Note again that we assume that all
 618 # builds under a given build root run on the same host platform.
 619 conf = Configure(main,
 620                  conf_dir = joinpath(build_root, '.scons_config'),
 621                  log_file = joinpath(build_root, 'scons_config.log'),
 622                  custom_tests = {
 623         'CheckMember' : CheckMember,
 624         })
 625
 626 # Check if we should compile a 64 bit binary on Mac OS X/Darwin
 627 try:
 628     import platform
 629     uname = platform.uname()
 630     if uname[0] == 'Darwin' and compareVersions(uname[2], '9.0.0') >= 0:
 631         if int(readCommand('sysctl -n hw.cpu64bit_capable')[0]):
 632             main.Append(CCFLAGS=['-arch', 'x86_64'])
 633             main.Append(CFLAGS=['-arch', 'x86_64'])
 634             main.Append(LINKFLAGS=['-arch', 'x86_64'])
 635             main.Append(ASFLAGS=['-arch', 'x86_64'])
 636 except:
 637     pass
 638
 639 # Recent versions of scons substitute a "Null" object for Configure()
 640 # when configuration isn't necessary, e.g., if the "--help" option is
 641 # present.  Unfortuantely this Null object always returns false,
 642 # breaking all our configuration checks.  We replace it with our own
 643 # more optimistic null object that returns True instead.
 644 if not conf:
 645     def NullCheck(*args, **kwargs):
 646         return True
 647
 648     class NullConf:
 649         def __init__(self, env):
 650             self.env = env
 651         def Finish(self):
 652             return self.env
 653         def __getattr__(self, mname):
 654             return NullCheck
 655
 656     conf = NullConf(main)
 657
 658 # Cache build files in the supplied directory.
 659 if main['M5_BUILD_CACHE']:
 660     print('Using build cache located at', main['M5_BUILD_CACHE'])
 661     CacheDir(main['M5_BUILD_CACHE'])
 662
 663 main['USE_PYTHON'] = not GetOption('without_python')
 664 if main['USE_PYTHON']:
 665     # Find Python include and library directories for embedding the
 666     # interpreter. We rely on python-config to resolve the appropriate
 667     # includes and linker flags. ParseConfig does not seem to understand
 668     # the more exotic linker flags such as -Xlinker and -export-dynamic so
 669     # we add them explicitly below. If you want to link in an alternate
 670     # version of python, see above for instructions on how to invoke
 671     # scons with the appropriate PATH set.
 672
 673     python_config = find_first_prog(main['PYTHON_CONFIG'])
 674     if python_config is None:
 675         error("Can't find a suitable python-config, tried %s" % \
 676               main['PYTHON_CONFIG'])
 677
 678     print("Info: Using Python config: %s" % (python_config, ))
 679     py_includes = readCommand([python_config, '--includes'],
 680                               exception='').split()
 681     py_includes = filter(lambda s: match(r'.*\/include\/.*',s), py_includes)
 682     # Strip the -I from the include folders before adding them to the
 683     # CPPPATH
 684     py_includes = map(lambda s: s[2:] if s.startswith('-I') else s, py_includes)
 685     main.Append(CPPPATH=py_includes)
 686
 687     # Read the linker flags and split them into libraries and other link
 688     # flags. The libraries are added later through the call the CheckLib.
 689     py_ld_flags = readCommand([python_config, '--ldflags'],
 690         exception='').split()
 691     py_libs = []
 692     for lib in py_ld_flags:
 693          if not lib.startswith('-l'):
 694              main.Append(LINKFLAGS=[lib])
 695          else:
 696              lib = lib[2:]
 697              if lib not in py_libs:
 698                  py_libs.append(lib)
 699
 700     # verify that this stuff works
 701     if not conf.CheckHeader('Python.h', '<>'):
 702         error("Check failed for Python.h header in",
 703                 ' '.join(py_includes), "\n"
 704               "Two possible reasons:\n"
 705               "1. Python headers are not installed (You can install the "
 706               "package python-dev on Ubuntu and RedHat)\n"
 707               "2. SCons is using a wrong C compiler. This can happen if "
 708               "CC has the wrong value.\n"
 709               "CC = %s" % main['CC'])
 710
 711     for lib in py_libs:
 712         if not conf.CheckLib(lib):
 713             error("Can't find library %s required by python." % lib)
 714
 715 # On Solaris you need to use libsocket for socket ops
 716 if not conf.CheckLibWithHeader(None, 'sys/socket.h', 'C++', 'accept(0,0,0);'):
 717    if not conf.CheckLibWithHeader('socket', 'sys/socket.h',
 718                                   'C++', 'accept(0,0,0);'):
 719        error("Can't find library with socket calls (e.g. accept()).")
 720
 721 # Check for zlib.  If the check passes, libz will be automatically
 722 # added to the LIBS environment variable.
 723 if not conf.CheckLibWithHeader('z', 'zlib.h', 'C++','zlibVersion();'):
 724     error('Did not find needed zlib compression library '
 725           'and/or zlib.h header file.\n'
 726           'Please install zlib and try again.')
 727
 728 # If we have the protobuf compiler, also make sure we have the
 729 # development libraries. If the check passes, libprotobuf will be
 730 # automatically added to the LIBS environment variable. After
 731 # this, we can use the HAVE_PROTOBUF flag to determine if we have
 732 # got both protoc and libprotobuf available.
 733 main['HAVE_PROTOBUF'] = main['HAVE_PROTOC'] and \
 734     conf.CheckLibWithHeader('protobuf', 'google/protobuf/message.h',
 735                             'C++', 'GOOGLE_PROTOBUF_VERIFY_VERSION;')
 736
 737 # Valgrind gets much less confused if you tell it when you're using
 738 # alternative stacks.
 739 main['HAVE_VALGRIND'] = conf.CheckCHeader('valgrind/valgrind.h')
 740
 741 # If we have the compiler but not the library, print another warning.
 742 if main['HAVE_PROTOC'] and not main['HAVE_PROTOBUF']:
 743     warning('Did not find protocol buffer library and/or headers.\n'
 744             'Please install libprotobuf-dev for tracing support.')
 745
 746 # Check for librt.
 747 have_posix_clock = \
 748     conf.CheckLibWithHeader(None, 'time.h', 'C',
 749                             'clock_nanosleep(0,0,NULL,NULL);') or \
 750     conf.CheckLibWithHeader('rt', 'time.h', 'C',
 751                             'clock_nanosleep(0,0,NULL,NULL);')
 752
 753 have_posix_timers = \
 754     conf.CheckLibWithHeader([None, 'rt'], [ 'time.h', 'signal.h' ], 'C',
 755                             'timer_create(CLOCK_MONOTONIC, NULL, NULL);')
 756
 757 if not GetOption('without_tcmalloc'):
 758     if conf.CheckLib('tcmalloc'):
 759         main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
 760     elif conf.CheckLib('tcmalloc_minimal'):
 761         main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
 762     else:
 763         warning("You can get a 12% performance improvement by "
 764                 "installing tcmalloc (libgoogle-perftools-dev package "
 765                 "on Ubuntu or RedHat).")
 766
 767
 768 # Detect back trace implementations. The last implementation in the
 769 # list will be used by default.
 770 backtrace_impls = [ "none" ]
 771
 772 backtrace_checker = 'char temp;' + \
 773     ' backtrace_symbols_fd((void*)&temp, 0, 0);'
 774 if conf.CheckLibWithHeader(None, 'execinfo.h', 'C', backtrace_checker):
 775     backtrace_impls.append("glibc")
 776 elif conf.CheckLibWithHeader('execinfo', 'execinfo.h', 'C',
 777                              backtrace_checker):
 778     # NetBSD and FreeBSD need libexecinfo.
 779     backtrace_impls.append("glibc")
 780     main.Append(LIBS=['execinfo'])
 781
 782 if backtrace_impls[-1] == "none":
 783     default_backtrace_impl = "none"
 784     warning("No suitable back trace implementation found.")
 785
 786 if not have_posix_clock:
 787     warning("Can't find library for POSIX clocks.")
 788
 789 # Check for <fenv.h> (C99 FP environment control)
 790 have_fenv = conf.CheckHeader('fenv.h', '<>')
 791 if not have_fenv:
 792     warning("Header file <fenv.h> not found.\n"
 793             "This host has no IEEE FP rounding mode control.")
 794
 795 # Check for <png.h> (libpng library needed if wanting to dump
 796 # frame buffer image in png format)
 797 have_png = conf.CheckHeader('png.h', '<>')
 798 if not have_png:
 799     warning("Header file <png.h> not found.\n"
 800             "This host has no libpng library.\n"
 801             "Disabling support for PNG framebuffers.")
 802
 803 # Check if we should enable KVM-based hardware virtualization. The API
 804 # we rely on exists since version 2.6.36 of the kernel, but somehow
 805 # the KVM_API_VERSION does not reflect the change. We test for one of
 806 # the types as a fall back.
 807 have_kvm = conf.CheckHeader('linux/kvm.h', '<>')
 808 if not have_kvm:
 809     print("Info: Compatible header file <linux/kvm.h> not found, "
 810           "disabling KVM support.")
 811
 812 # Check if the TUN/TAP driver is available.
 813 have_tuntap = conf.CheckHeader('linux/if_tun.h', '<>')
 814 if not have_tuntap:
 815     print("Info: Compatible header file <linux/if_tun.h> not found.")
 816
 817 # x86 needs support for xsave. We test for the structure here since we
 818 # won't be able to run new tests by the time we know which ISA we're
 819 # targeting.
 820 have_kvm_xsave = conf.CheckTypeSize('struct kvm_xsave',
 821                                     '#include <linux/kvm.h>') != 0
 822
 823 # Check if the requested target ISA is compatible with the host
 824 def is_isa_kvm_compatible(isa):
 825     try:
 826         import platform
 827         host_isa = platform.machine()
 828     except:
 829         warning("Failed to determine host ISA.")
 830         return False
 831
 832     if not have_posix_timers:
 833         warning("Can not enable KVM, host seems to lack support "
 834                 "for POSIX timers")
 835         return False
 836
 837     if isa == "arm":
 838         return host_isa in ( "armv7l", "aarch64" )
 839     elif isa == "x86":
 840         if host_isa != "x86_64":
 841             return False
 842
 843         if not have_kvm_xsave:
 844             warning("KVM on x86 requires xsave support in kernel headers.")
 845             return False
 846
 847         return True
 848     else:
 849         return False
 850
 851
 852 # Check if the exclude_host attribute is available. We want this to
 853 # get accurate instruction counts in KVM.
 854 main['HAVE_PERF_ATTR_EXCLUDE_HOST'] = conf.CheckMember(
 855     'linux/perf_event.h', 'struct perf_event_attr', 'exclude_host')
 856
 857 def check_hdf5():
 858     return \
 859         conf.CheckLibWithHeader('hdf5', 'hdf5.h', 'C',
 860                                 'H5Fcreate("", 0, 0, 0);') and \
 861         conf.CheckLibWithHeader('hdf5_cpp', 'H5Cpp.h', 'C++',
 862                                 'H5::H5File("", 0);')
 863
 864 def check_hdf5_pkg(name):
 865     print("Checking for %s using pkg-config..." % name, end="")
 866     if not have_pkg_config:
 867         print(" pkg-config not found")
 868         return False
 869
 870     try:
 871         main.ParseConfig('pkg-config --cflags-only-I --libs-only-L %s' % name)
 872         print(" yes")
 873         return True
 874     except:
 875         print(" no")
 876         return False
 877
 878 # Check if there is a pkg-config configuration for hdf5. If we find
 879 # it, setup the environment to enable linking and header inclusion. We
 880 # don't actually try to include any headers or link with hdf5 at this
 881 # stage.
 882 if not check_hdf5_pkg('hdf5-serial'):
 883     check_hdf5_pkg('hdf5')
 884
 885 # Check if the HDF5 libraries can be found. This check respects the
 886 # include path and library path provided by pkg-config. We perform
 887 # this check even if there isn't a pkg-config configuration for hdf5
 888 # since some installations don't use pkg-config.
 889 have_hdf5 = check_hdf5()
 890 if not have_hdf5:
 891     print("Warning: Couldn't find any HDF5 C++ libraries. Disabling")
 892     print("         HDF5 support.")
 893
 894 ######################################################################
 895 #
 896 # Finish the configuration
 897 #
 898 main = conf.Finish()
 899
 900 ######################################################################
 901 #
 902 # Collect all non-global variables
 903 #
 904
 905 # Define the universe of supported ISAs
 906 all_isa_list = [ ]
 907 all_gpu_isa_list = [ ]
 908 Export('all_isa_list')
 909 Export('all_gpu_isa_list')
 910
 911 class CpuModel(object):
 912     '''The CpuModel class encapsulates everything the ISA parser needs to
 913     know about a particular CPU model.'''
 914
 915     # Dict of available CPU model objects.  Accessible as CpuModel.dict.
 916     dict = {}
 917
 918     # Constructor.  Automatically adds models to CpuModel.dict.
 919     def __init__(self, name, default=False):
 920         self.name = name           # name of model
 921
 922         # This cpu is enabled by default
 923         self.default = default
 924
 925         # Add self to dict
 926         if name in CpuModel.dict:
 927             raise AttributeError("CpuModel '%s' already registered" % name)
 928         CpuModel.dict[name] = self
 929
 930 Export('CpuModel')
 931
 932 # Sticky variables get saved in the variables file so they persist from
 933 # one invocation to the next (unless overridden, in which case the new
 934 # value becomes sticky).
 935 sticky_vars = Variables(args=ARGUMENTS)
 936 Export('sticky_vars')
 937
 938 # Sticky variables that should be exported
 939 export_vars = []
 940 Export('export_vars')
 941
 942 # For Ruby
 943 all_protocols = []
 944 Export('all_protocols')
 945 protocol_dirs = []
 946 Export('protocol_dirs')
 947 slicc_includes = []
 948 Export('slicc_includes')
 949
 950 # Walk the tree and execute all SConsopts scripts that wil add to the
 951 # above variables
 952 if GetOption('verbose'):
 953     print("Reading SConsopts")
 954 for bdir in [ base_dir ] + extras_dir_list:
 955     if not isdir(bdir):
 956         error("Directory '%s' does not exist." % bdir)
 957     for root, dirs, files in os.walk(bdir):
 958         if 'SConsopts' in files:
 959             if GetOption('verbose'):
 960                 print("Reading", joinpath(root, 'SConsopts'))
 961             SConscript(joinpath(root, 'SConsopts'))
 962
 963 all_isa_list.sort()
 964 all_gpu_isa_list.sort()
 965
 966 sticky_vars.AddVariables(
 967     EnumVariable('TARGET_ISA', 'Target ISA', 'alpha', all_isa_list),
 968     EnumVariable('TARGET_GPU_ISA', 'Target GPU ISA', 'hsail', all_gpu_isa_list),
 969     ListVariable('CPU_MODELS', 'CPU models',
 970                  sorted(n for n,m in CpuModel.dict.iteritems() if m.default),
 971                  sorted(CpuModel.dict.keys())),
 972     BoolVariable('EFENCE', 'Link with Electric Fence malloc debugger',
 973                  False),
 974     BoolVariable('USE_SSE2',
 975                  'Compile for SSE2 (-msse2) to get IEEE FP on x86 hosts',
 976                  False),
 977     BoolVariable('USE_POSIX_CLOCK', 'Use POSIX Clocks', have_posix_clock),
 978     BoolVariable('USE_FENV', 'Use <fenv.h> IEEE mode control', have_fenv),
 979     BoolVariable('USE_PNG',  'Enable support for PNG images', have_png),
 980     BoolVariable('CP_ANNOTATE', 'Enable critical path annotation capability',
 981                  False),
 982     BoolVariable('USE_KVM', 'Enable hardware virtualized (KVM) CPU models',
 983                  have_kvm),
 984     BoolVariable('USE_TUNTAP',
 985                  'Enable using a tap device to bridge to the host network',
 986                  have_tuntap),
 987     BoolVariable('BUILD_GPU', 'Build the compute-GPU model', False),
 988     EnumVariable('PROTOCOL', 'Coherence protocol for Ruby', 'None',
 989                   all_protocols),
 990     EnumVariable('BACKTRACE_IMPL', 'Post-mortem dump implementation',
 991                  backtrace_impls[-1], backtrace_impls),
 992     ('NUMBER_BITS_PER_SET', 'Max elements in set (default 64)',
 993                  64),
 994     BoolVariable('USE_HDF5', 'Enable the HDF5 support', have_hdf5),
 995     )
 996
 997 # These variables get exported to #defines in config/*.hh (see src/SConscript).
 998 export_vars += ['USE_FENV', 'TARGET_ISA', 'TARGET_GPU_ISA', 'CP_ANNOTATE',
 999                 'USE_POSIX_CLOCK', 'USE_KVM', 'USE_TUNTAP', 'PROTOCOL',
1000                 'HAVE_PROTOBUF', 'HAVE_VALGRIND',
1001                 'HAVE_PERF_ATTR_EXCLUDE_HOST', 'USE_PNG',
1002                 'NUMBER_BITS_PER_SET', 'USE_HDF5']
1003
1004 ###################################################
1005 #
1006 # Define a SCons builder for configuration flag headers.
1007 #
1008 ###################################################
1009
1010 # This function generates a config header file that #defines the
1011 # variable symbol to the current variable setting (0 or 1).  The source
1012 # operands are the name of the variable and a Value node containing the
1013 # value of the variable.
1014 def build_config_file(target, source, env):
1015     (variable, value) = [s.get_contents() for s in source]
1016     f = file(str(target[0]), 'w')
1017     print('#define', variable, value, file=f)
1018     f.close()
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 main.Prepend(CPPPATH=Dir('ext/pybind11/include/'))
1108
1109 ###################################################
1110 #
1111 # This builder and wrapper method are used to set up a directory with
1112 # switching headers. Those are headers which are in a generic location and
1113 # that include more specific headers from a directory chosen at build time
1114 # based on the current build settings.
1115 #
1116 ###################################################
1117
1118 def build_switching_header(target, source, env):
1119     path = str(target[0])
1120     subdir = str(source[0])
1121     dp, fp = os.path.split(path)
1122     dp = os.path.relpath(os.path.realpath(dp),
1123                          os.path.realpath(env['BUILDDIR']))
1124     with open(path, 'w') as hdr:
1125         print('#include "%s/%s/%s"' % (dp, subdir, fp), file=hdr)
1126
1127 switching_header_action = MakeAction(build_switching_header,
1128                                      Transform('GENERATE'))
1129
1130 switching_header_builder = Builder(action=switching_header_action,
1131                                    source_factory=Value,
1132                                    single_source=True)
1133
1134 main.Append(BUILDERS = { 'SwitchingHeader': switching_header_builder })
1135
1136 def switching_headers(self, headers, source):
1137     for header in headers:
1138         self.SwitchingHeader(header, source)
1139
1140 main.AddMethod(switching_headers, 'SwitchingHeaders')
1141
1142 ###################################################
1143 #
1144 # Define build environments for selected configurations.
1145 #
1146 ###################################################
1147
1148 for variant_path in variant_paths:
1149     if not GetOption('silent'):
1150         print("Building in", variant_path)
1151
1152     # Make a copy of the build-root environment to use for this config.
1153     env = main.Clone()
1154     env['BUILDDIR'] = variant_path
1155
1156     # variant_dir is the tail component of build path, and is used to
1157     # determine the build parameters (e.g., 'ALPHA_SE')
1158     (build_root, variant_dir) = splitpath(variant_path)
1159
1160     # Set env variables according to the build directory config.
1161     sticky_vars.files = []
1162     # Variables for $BUILD_ROOT/$VARIANT_DIR are stored in
1163     # $BUILD_ROOT/variables/$VARIANT_DIR so you can nuke
1164     # $BUILD_ROOT/$VARIANT_DIR without losing your variables settings.
1165     current_vars_file = joinpath(build_root, 'variables', variant_dir)
1166     if isfile(current_vars_file):
1167         sticky_vars.files.append(current_vars_file)
1168         if not GetOption('silent'):
1169             print("Using saved variables file %s" % current_vars_file)
1170     elif variant_dir in ext_build_dirs:
1171         # Things in ext are built without a variant directory.
1172         continue
1173     else:
1174         # Build dir-specific variables file doesn't exist.
1175
1176         # Make sure the directory is there so we can create it later
1177         opt_dir = dirname(current_vars_file)
1178         if not isdir(opt_dir):
1179             mkdir(opt_dir)
1180
1181         # Get default build variables from source tree.  Variables are
1182         # normally determined by name of $VARIANT_DIR, but can be
1183         # overridden by '--default=' arg on command line.
1184         default = GetOption('default')
1185         opts_dir = joinpath(main.root.abspath, 'build_opts')
1186         if default:
1187             default_vars_files = [joinpath(build_root, 'variables', default),
1188                                   joinpath(opts_dir, default)]
1189         else:
1190             default_vars_files = [joinpath(opts_dir, variant_dir)]
1191         existing_files = filter(isfile, default_vars_files)
1192         if existing_files:
1193             default_vars_file = existing_files[0]
1194             sticky_vars.files.append(default_vars_file)
1195             print("Variables file %s not found,\n  using defaults in %s"
1196                   % (current_vars_file, default_vars_file))
1197         else:
1198             error("Cannot find variables file %s or default file(s) %s"
1199                   % (current_vars_file, ' or '.join(default_vars_files)))
1200             Exit(1)
1201
1202     # Apply current variable settings to env
1203     sticky_vars.Update(env)
1204
1205     help_texts["local_vars"] += \
1206         "Build variables for %s:\n" % variant_dir \
1207                  + sticky_vars.GenerateHelpText(env)
1208
1209     # Process variable settings.
1210
1211     if not have_fenv and env['USE_FENV']:
1212         warning("<fenv.h> not available; forcing USE_FENV to False in",
1213                 variant_dir + ".")
1214         env['USE_FENV'] = False
1215
1216     if not env['USE_FENV']:
1217         warning("No IEEE FP rounding mode control in", variant_dir + ".\n"
1218                 "FP results may deviate slightly from other platforms.")
1219
1220     if not have_png and env['USE_PNG']:
1221         warning("<png.h> not available; forcing USE_PNG to False in",
1222                 variant_dir + ".")
1223         env['USE_PNG'] = False
1224
1225     if env['USE_PNG']:
1226         env.Append(LIBS=['png'])
1227
1228     if env['EFENCE']:
1229         env.Append(LIBS=['efence'])
1230
1231     if env['USE_KVM']:
1232         if not have_kvm:
1233             warning("Can not enable KVM, host seems to lack KVM support")
1234             env['USE_KVM'] = False
1235         elif not is_isa_kvm_compatible(env['TARGET_ISA']):
1236             print("Info: KVM support disabled due to unsupported host and "
1237                   "target ISA combination")
1238             env['USE_KVM'] = False
1239
1240     if env['USE_TUNTAP']:
1241         if not have_tuntap:
1242             warning("Can't connect EtherTap with a tap device.")
1243             env['USE_TUNTAP'] = False
1244
1245     if env['BUILD_GPU']:
1246         env.Append(CPPDEFINES=['BUILD_GPU'])
1247
1248     # Warn about missing optional functionality
1249     if env['USE_KVM']:
1250         if not main['HAVE_PERF_ATTR_EXCLUDE_HOST']:
1251             warning("perf_event headers lack support for the exclude_host "
1252                     "attribute. KVM instruction counts will be inaccurate.")
1253
1254     # Save sticky variable settings back to current variables file
1255     sticky_vars.Save(current_vars_file, env)
1256
1257     if env['USE_SSE2']:
1258         env.Append(CCFLAGS=['-msse2'])
1259
1260     env.Append(CCFLAGS='$CCFLAGS_EXTRA')
1261     env.Append(LINKFLAGS='$LDFLAGS_EXTRA')
1262
1263     # The src/SConscript file sets up the build rules in 'env' according
1264     # to the configured variables.  It returns a list of environments,
1265     # one for each variant build (debug, opt, etc.)
1266     SConscript('src/SConscript', variant_dir = variant_path, exports = 'env')
1267
1268 # base help text
1269 Help('''
1270 Usage: scons [scons options] [build variables] [target(s)]
1271
1272 Extra scons options:
1273 %(options)s
1274
1275 Global build variables:
1276 %(global_vars)s
1277
1278 %(local_vars)s
1279 ''' % help_texts)