SConstruct

   1 # -*- mode:python -*-
   2
   3 # Copyright (c) 2013, 2015-2020 ARM Limited
   4 # All rights reserved.
   5 #
   6 # The license below extends only to copyright in the software and shall
   7 # not be construed as granting a license to any other intellectual
   8 # property including but not limited to intellectual property relating
   9 # to a hardware implementation of the functionality of the software
  10 # licensed hereunder.  You may use the software subject to the license
  11 # terms below provided that you ensure that this notice is replicated
  12 # unmodified and in its entirety in all distributions of the software,
  13 # modified or unmodified, in source code or in binary form.
  14 #
  15 # Copyright (c) 2011 Advanced Micro Devices, Inc.
  16 # Copyright (c) 2009 The Hewlett-Packard Development Company
  17 # Copyright (c) 2004-2005 The Regents of The University of Michigan
  18 # All rights reserved.
  19 #
  20 # Redistribution and use in source and binary forms, with or without
  21 # modification, are permitted provided that the following conditions are
  22 # met: redistributions of source code must retain the above copyright
  23 # notice, this list of conditions and the following disclaimer;
  24 # redistributions in binary form must reproduce the above copyright
  25 # notice, this list of conditions and the following disclaimer in the
  26 # documentation and/or other materials provided with the distribution;
  27 # neither the name of the copyright holders nor the names of its
  28 # contributors may be used to endorse or promote products derived from
  29 # this software without specific prior written permission.
  30 #
  31 # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32 # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33 # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  34 # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35 # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  36 # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  37 # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  38 # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  39 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  40 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  41 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  42
  43 ###################################################
  44 #
  45 # SCons top-level build description (SConstruct) file.
  46 #
  47 # While in this directory ('gem5'), just type 'scons' to build the default
  48 # configuration (see below), or type 'scons build/<CONFIG>/<binary>'
  49 # to build some other configuration (e.g., 'build/X86/gem5.opt' for
  50 # the optimized full-system version).
  51 #
  52 # You can build gem5 in a different directory as long as there is a
  53 # 'build/<CONFIG>' somewhere along the target path.  The build system
  54 # expects that all configs under the same build directory are being
  55 # built for the same host system.
  56 #
  57 # Examples:
  58 #
  59 #   The following two commands are equivalent.  The '-u' option tells
  60 #   scons to search up the directory tree for this SConstruct file.
  61 #   % cd <path-to-src>/gem5 ; scons build/X86/gem5.debug
  62 #   % cd <path-to-src>/gem5/build/X86; scons -u gem5.debug
  63 #
  64 #   The following two commands are equivalent and demonstrate building
  65 #   in a directory outside of the source tree.  The '-C' option tells
  66 #   scons to chdir to the specified directory to find this SConstruct
  67 #   file.
  68 #   % cd <path-to-src>/gem5 ; scons /local/foo/build/X86/gem5.debug
  69 #   % cd /local/foo/build/X86; scons -C <path-to-src>/gem5 gem5.debug
  70 #
  71 # You can use 'scons -H' to print scons options.  If you're in this
  72 # 'gem5' directory (or use -u or -C to tell scons where to find this
  73 # file), you can use 'scons -h' to print all the gem5-specific build
  74 # options as well.
  75 #
  76 ###################################################
  77
  78 from __future__ import print_function
  79
  80 # Global Python includes
  81 import itertools
  82 import os
  83 import re
  84 import shutil
  85 import subprocess
  86 import sys
  87
  88 from os import mkdir, environ
  89 from os.path import abspath, basename, dirname, expanduser, normpath
  90 from os.path import exists,  isdir, isfile
  91 from os.path import join as joinpath, split as splitpath
  92 from re import match
  93
  94 # SCons includes
  95 import SCons
  96 import SCons.Node
  97 import SCons.Node.FS
  98
  99 from m5.util import compareVersions, readCommand
 100
 101 help_texts = {
 102     "options" : "",
 103     "global_vars" : "",
 104     "local_vars" : ""
 105 }
 106
 107 Export("help_texts")
 108
 109
 110 # There's a bug in scons in that (1) by default, the help texts from
 111 # AddOption() are supposed to be displayed when you type 'scons -h'
 112 # and (2) you can override the help displayed by 'scons -h' using the
 113 # Help() function, but these two features are incompatible: once
 114 # you've overridden the help text using Help(), there's no way to get
 115 # at the help texts from AddOptions.  See:
 116 #     http://scons.tigris.org/issues/show_bug.cgi?id=2356
 117 #     http://scons.tigris.org/issues/show_bug.cgi?id=2611
 118 # This hack lets us extract the help text from AddOptions and
 119 # re-inject it via Help().  Ideally someday this bug will be fixed and
 120 # we can just use AddOption directly.
 121 def AddLocalOption(*args, **kwargs):
 122     col_width = 30
 123
 124     help = "  " + ", ".join(args)
 125     if "help" in kwargs:
 126         length = len(help)
 127         if length >= col_width:
 128             help += "\n" + " " * col_width
 129         else:
 130             help += " " * (col_width - length)
 131         help += kwargs["help"]
 132     help_texts["options"] += help + "\n"
 133
 134     AddOption(*args, **kwargs)
 135
 136 AddLocalOption('--colors', dest='use_colors', action='store_true',
 137                help="Add color to abbreviated scons output")
 138 AddLocalOption('--no-colors', dest='use_colors', action='store_false',
 139                help="Don't add color to abbreviated scons output")
 140 AddLocalOption('--with-cxx-config', dest='with_cxx_config',
 141                action='store_true',
 142                help="Build with support for C++-based configuration")
 143 AddLocalOption('--default', dest='default', type='string', action='store',
 144                help='Override which build_opts file to use for defaults')
 145 AddLocalOption('--ignore-style', dest='ignore_style', action='store_true',
 146                help='Disable style checking hooks')
 147 AddLocalOption('--gold-linker', dest='gold_linker', action='store_true',
 148                help='Use the gold linker')
 149 AddLocalOption('--no-lto', dest='no_lto', action='store_true',
 150                help='Disable Link-Time Optimization for fast')
 151 AddLocalOption('--force-lto', dest='force_lto', action='store_true',
 152                help='Use Link-Time Optimization instead of partial linking' +
 153                     ' when the compiler doesn\'t support using them together.')
 154 AddLocalOption('--update-ref', dest='update_ref', action='store_true',
 155                help='Update test reference outputs')
 156 AddLocalOption('--verbose', dest='verbose', action='store_true',
 157                help='Print full tool command lines')
 158 AddLocalOption('--without-python', dest='without_python',
 159                action='store_true',
 160                help='Build without Python configuration support')
 161 AddLocalOption('--without-tcmalloc', dest='without_tcmalloc',
 162                action='store_true',
 163                help='Disable linking against tcmalloc')
 164 AddLocalOption('--with-ubsan', dest='with_ubsan', action='store_true',
 165                help='Build with Undefined Behavior Sanitizer if available')
 166 AddLocalOption('--with-asan', dest='with_asan', action='store_true',
 167                help='Build with Address Sanitizer if available')
 168 AddLocalOption('--with-systemc-tests', dest='with_systemc_tests',
 169                action='store_true', help='Build systemc tests')
 170
 171 from gem5_scons import Transform, error, warning
 172
 173 if GetOption('no_lto') and GetOption('force_lto'):
 174     error('--no-lto and --force-lto are mutually exclusive')
 175
 176 ########################################################################
 177 #
 178 # Set up the main build environment.
 179 #
 180 ########################################################################
 181
 182 main = Environment()
 183
 184 from gem5_scons.util import get_termcap
 185 termcap = get_termcap()
 186
 187 main_dict_keys = main.Dictionary().keys()
 188
 189 # Check that we have a C/C++ compiler
 190 if not ('CC' in main_dict_keys and 'CXX' in main_dict_keys):
 191     error("No C++ compiler installed (package g++ on Ubuntu and RedHat)")
 192
 193 ###################################################
 194 #
 195 # Figure out which configurations to set up based on the path(s) of
 196 # the target(s).
 197 #
 198 ###################################################
 199
 200 # Find default configuration & binary.
 201 Default(environ.get('M5_DEFAULT_BINARY', 'build/ARM/gem5.debug'))
 202
 203 # helper function: find last occurrence of element in list
 204 def rfind(l, elt, offs = -1):
 205     for i in range(len(l)+offs, 0, -1):
 206         if l[i] == elt:
 207             return i
 208     raise ValueError("element not found")
 209
 210 # Take a list of paths (or SCons Nodes) and return a list with all
 211 # paths made absolute and ~-expanded.  Paths will be interpreted
 212 # relative to the launch directory unless a different root is provided
 213 def makePathListAbsolute(path_list, root=GetLaunchDir()):
 214     return [abspath(joinpath(root, expanduser(str(p))))
 215             for p in path_list]
 216
 217 def find_first_prog(prog_names):
 218     """Find the absolute path to the first existing binary in prog_names"""
 219
 220     if not isinstance(prog_names, (list, tuple)):
 221         prog_names = [ prog_names ]
 222
 223     for p in prog_names:
 224         p = main.WhereIs(p)
 225         if p is not None:
 226             return p
 227
 228     return None
 229
 230 # Each target must have 'build' in the interior of the path; the
 231 # directory below this will determine the build parameters.  For
 232 # example, for target 'foo/bar/build/X86/arch/x86/blah.do' we
 233 # recognize that X86 specifies the configuration because it
 234 # follow 'build' in the build path.
 235
 236 # The funky assignment to "[:]" is needed to replace the list contents
 237 # in place rather than reassign the symbol to a new list, which
 238 # doesn't work (obviously!).
 239 BUILD_TARGETS[:] = makePathListAbsolute(BUILD_TARGETS)
 240
 241 # Generate a list of the unique build roots and configs that the
 242 # collected targets reference.
 243 variant_paths = []
 244 build_root = None
 245 for t in BUILD_TARGETS:
 246     path_dirs = t.split('/')
 247     try:
 248         build_top = rfind(path_dirs, 'build', -2)
 249     except:
 250         error("No non-leaf 'build' dir found on target path.", t)
 251     this_build_root = joinpath('/',*path_dirs[:build_top+1])
 252     if not build_root:
 253         build_root = this_build_root
 254     else:
 255         if this_build_root != build_root:
 256             error("build targets not under same build root\n"
 257                   "  %s\n  %s" % (build_root, this_build_root))
 258     variant_path = joinpath('/',*path_dirs[:build_top+2])
 259     if variant_path not in variant_paths:
 260         variant_paths.append(variant_path)
 261
 262 # Make sure build_root exists (might not if this is the first build there)
 263 if not isdir(build_root):
 264     mkdir(build_root)
 265 main['BUILDROOT'] = build_root
 266
 267 Export('main')
 268
 269 main.SConsignFile(joinpath(build_root, "sconsign"))
 270
 271 # Default duplicate option is to use hard links, but this messes up
 272 # when you use emacs to edit a file in the target dir, as emacs moves
 273 # file to file~ then copies to file, breaking the link.  Symbolic
 274 # (soft) links work better.
 275 main.SetOption('duplicate', 'soft-copy')
 276
 277 #
 278 # Set up global sticky variables... these are common to an entire build
 279 # tree (not specific to a particular build like X86)
 280 #
 281
 282 global_vars_file = joinpath(build_root, 'variables.global')
 283
 284 global_vars = Variables(global_vars_file, args=ARGUMENTS)
 285
 286 global_vars.AddVariables(
 287     ('CC', 'C compiler', environ.get('CC', main['CC'])),
 288     ('CXX', 'C++ compiler', environ.get('CXX', main['CXX'])),
 289     ('CCFLAGS_EXTRA', 'Extra C and C++ compiler flags', ''),
 290     ('LDFLAGS_EXTRA', 'Extra linker flags', ''),
 291     ('PYTHON_CONFIG', 'Python config binary to use',
 292      [ 'python2.7-config', 'python-config' ]),
 293     ('PROTOC', 'protoc tool', environ.get('PROTOC', 'protoc')),
 294     ('BATCH', 'Use batch pool for build and tests', False),
 295     ('BATCH_CMD', 'Batch pool submission command name', 'qdo'),
 296     ('M5_BUILD_CACHE', 'Cache built objects in this directory', False),
 297     ('EXTRAS', 'Add extra directories to the compilation', '')
 298     )
 299
 300 # Update main environment with values from ARGUMENTS & global_vars_file
 301 global_vars.Update(main)
 302 help_texts["global_vars"] += global_vars.GenerateHelpText(main)
 303
 304 # Save sticky variable settings back to current variables file
 305 global_vars.Save(global_vars_file, main)
 306
 307 # Parse EXTRAS variable to build list of all directories where we're
 308 # look for sources etc.  This list is exported as extras_dir_list.
 309 base_dir = main.srcdir.abspath
 310 if main['EXTRAS']:
 311     extras_dir_list = makePathListAbsolute(main['EXTRAS'].split(':'))
 312 else:
 313     extras_dir_list = []
 314
 315 Export('base_dir')
 316 Export('extras_dir_list')
 317
 318 # the ext directory should be on the #includes path
 319 main.Append(CPPPATH=[Dir('ext')])
 320
 321 # Add shared top-level headers
 322 main.Prepend(CPPPATH=Dir('include'))
 323
 324 if GetOption('verbose'):
 325     def MakeAction(action, string, *args, **kwargs):
 326         return Action(action, *args, **kwargs)
 327 else:
 328     MakeAction = Action
 329     main['CCCOMSTR']        = Transform("CC")
 330     main['CXXCOMSTR']       = Transform("CXX")
 331     main['ASCOMSTR']        = Transform("AS")
 332     main['ARCOMSTR']        = Transform("AR", 0)
 333     main['LINKCOMSTR']      = Transform("LINK", 0)
 334     main['SHLINKCOMSTR']    = Transform("SHLINK", 0)
 335     main['RANLIBCOMSTR']    = Transform("RANLIB", 0)
 336     main['M4COMSTR']        = Transform("M4")
 337     main['SHCCCOMSTR']      = Transform("SHCC")
 338     main['SHCXXCOMSTR']     = Transform("SHCXX")
 339 Export('MakeAction')
 340
 341 # Initialize the Link-Time Optimization (LTO) flags
 342 main['LTO_CCFLAGS'] = []
 343 main['LTO_LDFLAGS'] = []
 344
 345 # According to the readme, tcmalloc works best if the compiler doesn't
 346 # assume that we're using the builtin malloc and friends. These flags
 347 # are compiler-specific, so we need to set them after we detect which
 348 # compiler we're using.
 349 main['TCMALLOC_CCFLAGS'] = []
 350
 351 CXX_version = readCommand([main['CXX'],'--version'], exception=False)
 352 CXX_V = readCommand([main['CXX'],'-V'], exception=False)
 353
 354 main['GCC'] = CXX_version and CXX_version.find('g++') >= 0
 355 main['CLANG'] = CXX_version and CXX_version.find('clang') >= 0
 356 if main['GCC'] + main['CLANG'] > 1:
 357     error('Two compilers enabled at once?')
 358
 359 # Set up default C++ compiler flags
 360 if main['GCC'] or main['CLANG']:
 361     # As gcc and clang share many flags, do the common parts here
 362     main.Append(CCFLAGS=['-pipe'])
 363     main.Append(CCFLAGS=['-fno-strict-aliasing'])
 364     # Enable -Wall and -Wextra and then disable the few warnings that
 365     # we consistently violate
 366     main.Append(CCFLAGS=['-Wall', '-Wundef', '-Wextra',
 367                          '-Wno-sign-compare', '-Wno-unused-parameter'])
 368     # We always compile using C++11
 369     main.Append(CXXFLAGS=['-std=c++11'])
 370     if sys.platform.startswith('freebsd'):
 371         main.Append(CCFLAGS=['-I/usr/local/include'])
 372         main.Append(CXXFLAGS=['-I/usr/local/include'])
 373
 374     main.Append(LINKFLAGS='-Wl,--as-needed')
 375     main['FILTER_PSHLINKFLAGS'] = lambda x: str(x).replace(' -shared', '')
 376     main['PSHLINKFLAGS'] = main.subst('${FILTER_PSHLINKFLAGS(SHLINKFLAGS)}')
 377     if GetOption('gold_linker'):
 378         main.Append(LINKFLAGS='-fuse-ld=gold')
 379     main['PLINKFLAGS'] = main.get('LINKFLAGS')
 380     shared_partial_flags = ['-r', '-nostdlib']
 381     main.Append(PSHLINKFLAGS=shared_partial_flags)
 382     main.Append(PLINKFLAGS=shared_partial_flags)
 383
 384     # Treat warnings as errors but white list some warnings that we
 385     # want to allow (e.g., deprecation warnings).
 386     main.Append(CCFLAGS=['-Werror',
 387                          '-Wno-error=deprecated-declarations',
 388                          '-Wno-error=deprecated',
 389                         ])
 390 else:
 391     error('\n'.join((
 392           "Don't know what compiler options to use for your compiler.",
 393           "compiler: " + main['CXX'],
 394           "version: " + CXX_version.replace('\n', '<nl>') if
 395                 CXX_version else 'COMMAND NOT FOUND!',
 396           "If you're trying to use a compiler other than GCC",
 397           "or clang, there appears to be something wrong with your",
 398           "environment.",
 399           "",
 400           "If you are trying to use a compiler other than those listed",
 401           "above you will need to ease fix SConstruct and ",
 402           "src/SConscript to support that compiler.")))
 403
 404 if main['GCC']:
 405     # Check for a supported version of gcc. >= 4.8 is chosen for its
 406     # level of c++11 support. See
 407     # http://gcc.gnu.org/projects/cxx0x.html for details.
 408     gcc_version = readCommand([main['CXX'], '-dumpversion'], exception=False)
 409     if compareVersions(gcc_version, "4.8") < 0:
 410         error('gcc version 4.8 or newer required.\n'
 411               'Installed version:', gcc_version)
 412         Exit(1)
 413
 414     main['GCC_VERSION'] = gcc_version
 415
 416     if compareVersions(gcc_version, '4.9') >= 0:
 417         # Incremental linking with LTO is currently broken in gcc versions
 418         # 4.9 and above. A version where everything works completely hasn't
 419         # yet been identified.
 420         #
 421         # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67548
 422         main['BROKEN_INCREMENTAL_LTO'] = True
 423     if compareVersions(gcc_version, '6.0') >= 0:
 424         # gcc versions 6.0 and greater accept an -flinker-output flag which
 425         # selects what type of output the linker should generate. This is
 426         # necessary for incremental lto to work, but is also broken in
 427         # current versions of gcc. It may not be necessary in future
 428         # versions. We add it here since it might be, and as a reminder that
 429         # it exists. It's excluded if lto is being forced.
 430         #
 431         # https://gcc.gnu.org/gcc-6/changes.html
 432         # https://gcc.gnu.org/ml/gcc-patches/2015-11/msg03161.html
 433         # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69866
 434         if not GetOption('force_lto'):
 435             main.Append(PSHLINKFLAGS='-flinker-output=rel')
 436             main.Append(PLINKFLAGS='-flinker-output=rel')
 437
 438     disable_lto = GetOption('no_lto')
 439     if not disable_lto and main.get('BROKEN_INCREMENTAL_LTO', False) and \
 440             not GetOption('force_lto'):
 441         warning('Warning: Your compiler doesn\'t support incremental linking '
 442                 'and lto at the same time, so lto is being disabled. To force '
 443                 'lto on anyway, use the --force-lto option. That will disable '
 444                 'partial linking.')
 445         disable_lto = True
 446
 447     # Add the appropriate Link-Time Optimization (LTO) flags
 448     # unless LTO is explicitly turned off. Note that these flags
 449     # are only used by the fast target.
 450     if not disable_lto:
 451         # Pass the LTO flag when compiling to produce GIMPLE
 452         # output, we merely create the flags here and only append
 453         # them later
 454         main['LTO_CCFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
 455
 456         # Use the same amount of jobs for LTO as we are running
 457         # scons with
 458         main['LTO_LDFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
 459
 460     main.Append(TCMALLOC_CCFLAGS=['-fno-builtin-malloc', '-fno-builtin-calloc',
 461                                   '-fno-builtin-realloc', '-fno-builtin-free'])
 462
 463 elif main['CLANG']:
 464     # Check for a supported version of clang, >= 3.1 is needed to
 465     # support similar features as gcc 4.8. See
 466     # http://clang.llvm.org/cxx_status.html for details
 467     clang_version_re = re.compile(".* version (\d+\.\d+)")
 468     clang_version_match = clang_version_re.search(CXX_version)
 469     if (clang_version_match):
 470         clang_version = clang_version_match.groups()[0]
 471         if compareVersions(clang_version, "3.1") < 0:
 472             error('clang version 3.1 or newer required.\n'
 473                   'Installed version:', clang_version)
 474     else:
 475         error('Unable to determine clang version.')
 476
 477     # clang has a few additional warnings that we disable, extraneous
 478     # parantheses are allowed due to Ruby's printing of the AST,
 479     # finally self assignments are allowed as the generated CPU code
 480     # is relying on this
 481     main.Append(CCFLAGS=['-Wno-parentheses',
 482                          '-Wno-self-assign',
 483                          # Some versions of libstdc++ (4.8?) seem to
 484                          # use struct hash and class hash
 485                          # interchangeably.
 486                          '-Wno-mismatched-tags',
 487                          ])
 488
 489     main.Append(TCMALLOC_CCFLAGS=['-fno-builtin'])
 490
 491     # On Mac OS X/Darwin we need to also use libc++ (part of XCode) as
 492     # opposed to libstdc++, as the later is dated.
 493     if sys.platform == "darwin":
 494         main.Append(CXXFLAGS=['-stdlib=libc++'])
 495         main.Append(LIBS=['c++'])
 496
 497     # On FreeBSD we need libthr.
 498     if sys.platform.startswith('freebsd'):
 499         main.Append(LIBS=['thr'])
 500
 501 # Add sanitizers flags
 502 sanitizers=[]
 503 if GetOption('with_ubsan'):
 504     # Only gcc >= 4.9 supports UBSan, so check both the version
 505     # and the command-line option before adding the compiler and
 506     # linker flags.
 507     if not main['GCC'] or compareVersions(main['GCC_VERSION'], '4.9') >= 0:
 508         sanitizers.append('undefined')
 509 if GetOption('with_asan'):
 510     # Available for gcc >= 4.8 or llvm >= 3.1 both a requirement
 511     # by the build system
 512     sanitizers.append('address')
 513 if sanitizers:
 514     sanitizers = ','.join(sanitizers)
 515     if main['GCC'] or main['CLANG']:
 516         main.Append(CCFLAGS=['-fsanitize=%s' % sanitizers,
 517                              '-fno-omit-frame-pointer'],
 518                     LINKFLAGS='-fsanitize=%s' % sanitizers)
 519     else:
 520         warning("Don't know how to enable %s sanitizer(s) for your "
 521                 "compiler." % sanitizers)
 522
 523 # Set up common yacc/bison flags (needed for Ruby)
 524 main['YACCFLAGS'] = '-d'
 525 main['YACCHXXFILESUFFIX'] = '.hh'
 526
 527 # Do this after we save setting back, or else we'll tack on an
 528 # extra 'qdo' every time we run scons.
 529 if main['BATCH']:
 530     main['CC']     = main['BATCH_CMD'] + ' ' + main['CC']
 531     main['CXX']    = main['BATCH_CMD'] + ' ' + main['CXX']
 532     main['AS']     = main['BATCH_CMD'] + ' ' + main['AS']
 533     main['AR']     = main['BATCH_CMD'] + ' ' + main['AR']
 534     main['RANLIB'] = main['BATCH_CMD'] + ' ' + main['RANLIB']
 535
 536 if sys.platform == 'cygwin':
 537     # cygwin has some header file issues...
 538     main.Append(CCFLAGS=["-Wno-uninitialized"])
 539
 540
 541 have_pkg_config = readCommand(['pkg-config', '--version'], exception='')
 542
 543 # Check for the protobuf compiler
 544 try:
 545     main['HAVE_PROTOC'] = True
 546     protoc_version = readCommand([main['PROTOC'], '--version']).split()
 547
 548     # First two words should be "libprotoc x.y.z"
 549     if len(protoc_version) < 2 or protoc_version[0] != 'libprotoc':
 550         warning('Protocol buffer compiler (protoc) not found.\n'
 551                 'Please install protobuf-compiler for tracing support.')
 552         main['HAVE_PROTOC'] = False
 553     else:
 554         # Based on the availability of the compress stream wrappers,
 555         # require 2.1.0
 556         min_protoc_version = '2.1.0'
 557         if compareVersions(protoc_version[1], min_protoc_version) < 0:
 558             warning('protoc version', min_protoc_version,
 559                     'or newer required.\n'
 560                     'Installed version:', protoc_version[1])
 561             main['HAVE_PROTOC'] = False
 562         else:
 563             # Attempt to determine the appropriate include path and
 564             # library path using pkg-config, that means we also need to
 565             # check for pkg-config. Note that it is possible to use
 566             # protobuf without the involvement of pkg-config. Later on we
 567             # check go a library config check and at that point the test
 568             # will fail if libprotobuf cannot be found.
 569             if have_pkg_config:
 570                 try:
 571                     # Attempt to establish what linking flags to add for
 572                     # protobuf
 573                     # using pkg-config
 574                     main.ParseConfig(
 575                             'pkg-config --cflags --libs-only-L protobuf')
 576                 except:
 577                     warning('pkg-config could not get protobuf flags.')
 578 except Exception as e:
 579     warning('While checking protoc version:', str(e))
 580     main['HAVE_PROTOC'] = False
 581
 582 # Check for 'timeout' from GNU coreutils. If present, regressions will
 583 # be run with a time limit. We require version 8.13 since we rely on
 584 # support for the '--foreground' option.
 585 if sys.platform.startswith('freebsd'):
 586     timeout_lines = readCommand(['gtimeout', '--version'],
 587                                 exception='').splitlines()
 588 else:
 589     timeout_lines = readCommand(['timeout', '--version'],
 590                                 exception='').splitlines()
 591 # Get the first line and tokenize it
 592 timeout_version = timeout_lines[0].split() if timeout_lines else []
 593 main['TIMEOUT'] =  timeout_version and \
 594     compareVersions(timeout_version[-1], '8.13') >= 0
 595
 596 # Add a custom Check function to test for structure members.
 597 def CheckMember(context, include, decl, member, include_quotes="<>"):
 598     context.Message("Checking for member %s in %s..." %
 599                     (member, decl))
 600     text = """
 601 #include %(header)s
 602 int main(){
 603   %(decl)s test;
 604   (void)test.%(member)s;
 605   return 0;
 606 };
 607 """ % { "header" : include_quotes[0] + include + include_quotes[1],
 608         "decl" : decl,
 609         "member" : member,
 610         }
 611
 612     ret = context.TryCompile(text, extension=".cc")
 613     context.Result(ret)
 614     return ret
 615
 616 # Platform-specific configuration.  Note again that we assume that all
 617 # builds under a given build root run on the same host platform.
 618 conf = Configure(main,
 619                  conf_dir = joinpath(build_root, '.scons_config'),
 620                  log_file = joinpath(build_root, 'scons_config.log'),
 621                  custom_tests = {
 622         'CheckMember' : CheckMember,
 623         })
 624
 625 # Check if we should compile a 64 bit binary on Mac OS X/Darwin
 626 try:
 627     import platform
 628     uname = platform.uname()
 629     if uname[0] == 'Darwin' and compareVersions(uname[2], '9.0.0') >= 0:
 630         if int(readCommand('sysctl -n hw.cpu64bit_capable')[0]):
 631             main.Append(CCFLAGS=['-arch', 'x86_64'])
 632             main.Append(CFLAGS=['-arch', 'x86_64'])
 633             main.Append(LINKFLAGS=['-arch', 'x86_64'])
 634             main.Append(ASFLAGS=['-arch', 'x86_64'])
 635 except:
 636     pass
 637
 638 # Recent versions of scons substitute a "Null" object for Configure()
 639 # when configuration isn't necessary, e.g., if the "--help" option is
 640 # present.  Unfortuantely this Null object always returns false,
 641 # breaking all our configuration checks.  We replace it with our own
 642 # more optimistic null object that returns True instead.
 643 if not conf:
 644     def NullCheck(*args, **kwargs):
 645         return True
 646
 647     class NullConf:
 648         def __init__(self, env):
 649             self.env = env
 650         def Finish(self):
 651             return self.env
 652         def __getattr__(self, mname):
 653             return NullCheck
 654
 655     conf = NullConf(main)
 656
 657 # Cache build files in the supplied directory.
 658 if main['M5_BUILD_CACHE']:
 659     print('Using build cache located at', main['M5_BUILD_CACHE'])
 660     CacheDir(main['M5_BUILD_CACHE'])
 661
 662 main['USE_PYTHON'] = not GetOption('without_python')
 663 if main['USE_PYTHON']:
 664     # Find Python include and library directories for embedding the
 665     # interpreter. We rely on python-config to resolve the appropriate
 666     # includes and linker flags. ParseConfig does not seem to understand
 667     # the more exotic linker flags such as -Xlinker and -export-dynamic so
 668     # we add them explicitly below. If you want to link in an alternate
 669     # version of python, see above for instructions on how to invoke
 670     # scons with the appropriate PATH set.
 671
 672     python_config = find_first_prog(main['PYTHON_CONFIG'])
 673     if python_config is None:
 674         error("Can't find a suitable python-config, tried %s" % \
 675               main['PYTHON_CONFIG'])
 676
 677     print("Info: Using Python config: %s" % (python_config, ))
 678     py_includes = readCommand([python_config, '--includes'],
 679                               exception='').split()
 680     py_includes = list(filter(
 681         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 = list(map(
 685         lambda s: s[2:] if s.startswith('-I') else s, py_includes))
 686     main.Append(CPPPATH=py_includes)
 687
 688     # Read the linker flags and split them into libraries and other link
 689     # flags. The libraries are added later through the call the CheckLib.
 690     py_ld_flags = readCommand([python_config, '--ldflags'],
 691         exception='').split()
 692     py_libs = []
 693     for lib in py_ld_flags:
 694          if not lib.startswith('-l'):
 695              main.Append(LINKFLAGS=[lib])
 696          else:
 697              lib = lib[2:]
 698              if lib not in py_libs:
 699                  py_libs.append(lib)
 700
 701     # verify that this stuff works
 702     if not conf.CheckHeader('Python.h', '<>'):
 703         error("Check failed for Python.h header in",
 704                 ' '.join(py_includes), "\n"
 705               "Two possible reasons:\n"
 706               "1. Python headers are not installed (You can install the "
 707               "package python-dev on Ubuntu and RedHat)\n"
 708               "2. SCons is using a wrong C compiler. This can happen if "
 709               "CC has the wrong value.\n"
 710               "CC = %s" % main['CC'])
 711
 712     for lib in py_libs:
 713         if not conf.CheckLib(lib):
 714             error("Can't find library %s required by python." % lib)
 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 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., 'X86')
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 = list(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)