SConstruct

   1 # -*- mode:python -*-
   2
   3 # Copyright (c) 2013, 2015 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 # Check for recent-enough Python and SCons versions.
  82 try:
  83     # Really old versions of scons only take two options for the
  84     # function, so check once without the revision and once with the
  85     # revision, the first instance will fail for stuff other than
  86     # 0.98, and the second will fail for 0.98.0
  87     EnsureSConsVersion(0, 98)
  88     EnsureSConsVersion(0, 98, 1)
  89 except SystemExit, e:
  90     print """
  91 For more details, see:
  92     http://gem5.org/Dependencies
  93 """
  94     raise
  95
  96 # We ensure the python version early because because python-config
  97 # requires python 2.5
  98 try:
  99     EnsurePythonVersion(2, 5)
 100 except SystemExit, e:
 101     print """
 102 You can use a non-default installation of the Python interpreter by
 103 rearranging your PATH so that scons finds the non-default 'python' and
 104 'python-config' first.
 105
 106 For more details, see:
 107     http://gem5.org/wiki/index.php/Using_a_non-default_Python_installation
 108 """
 109     raise
 110
 111 # Global Python includes
 112 import itertools
 113 import os
 114 import re
 115 import subprocess
 116 import sys
 117
 118 from os import mkdir, environ
 119 from os.path import abspath, basename, dirname, expanduser, normpath
 120 from os.path import exists,  isdir, isfile
 121 from os.path import join as joinpath, split as splitpath
 122
 123 # SCons includes
 124 import SCons
 125 import SCons.Node
 126
 127 extra_python_paths = [
 128     Dir('src/python').srcnode().abspath, # gem5 includes
 129     Dir('ext/ply').srcnode().abspath, # ply is used by several files
 130     ]
 131
 132 sys.path[1:1] = extra_python_paths
 133
 134 from m5.util import compareVersions, readCommand
 135 from m5.util.terminal import get_termcap
 136
 137 help_texts = {
 138     "options" : "",
 139     "global_vars" : "",
 140     "local_vars" : ""
 141 }
 142
 143 Export("help_texts")
 144
 145
 146 # There's a bug in scons in that (1) by default, the help texts from
 147 # AddOption() are supposed to be displayed when you type 'scons -h'
 148 # and (2) you can override the help displayed by 'scons -h' using the
 149 # Help() function, but these two features are incompatible: once
 150 # you've overridden the help text using Help(), there's no way to get
 151 # at the help texts from AddOptions.  See:
 152 #     http://scons.tigris.org/issues/show_bug.cgi?id=2356
 153 #     http://scons.tigris.org/issues/show_bug.cgi?id=2611
 154 # This hack lets us extract the help text from AddOptions and
 155 # re-inject it via Help().  Ideally someday this bug will be fixed and
 156 # we can just use AddOption directly.
 157 def AddLocalOption(*args, **kwargs):
 158     col_width = 30
 159
 160     help = "  " + ", ".join(args)
 161     if "help" in kwargs:
 162         length = len(help)
 163         if length >= col_width:
 164             help += "\n" + " " * col_width
 165         else:
 166             help += " " * (col_width - length)
 167         help += kwargs["help"]
 168     help_texts["options"] += help + "\n"
 169
 170     AddOption(*args, **kwargs)
 171
 172 AddLocalOption('--colors', dest='use_colors', action='store_true',
 173                help="Add color to abbreviated scons output")
 174 AddLocalOption('--no-colors', dest='use_colors', action='store_false',
 175                help="Don't add color to abbreviated scons output")
 176 AddLocalOption('--with-cxx-config', dest='with_cxx_config',
 177                action='store_true',
 178                help="Build with support for C++-based configuration")
 179 AddLocalOption('--default', dest='default', type='string', action='store',
 180                help='Override which build_opts file to use for defaults')
 181 AddLocalOption('--ignore-style', dest='ignore_style', action='store_true',
 182                help='Disable style checking hooks')
 183 AddLocalOption('--no-lto', dest='no_lto', action='store_true',
 184                help='Disable Link-Time Optimization for fast')
 185 AddLocalOption('--update-ref', dest='update_ref', action='store_true',
 186                help='Update test reference outputs')
 187 AddLocalOption('--verbose', dest='verbose', action='store_true',
 188                help='Print full tool command lines')
 189 AddLocalOption('--without-python', dest='without_python',
 190                action='store_true',
 191                help='Build without Python configuration support')
 192 AddLocalOption('--without-tcmalloc', dest='without_tcmalloc',
 193                action='store_true',
 194                help='Disable linking against tcmalloc')
 195 AddLocalOption('--with-ubsan', dest='with_ubsan', action='store_true',
 196                help='Build with Undefined Behavior Sanitizer if available')
 197
 198 termcap = get_termcap(GetOption('use_colors'))
 199
 200 ########################################################################
 201 #
 202 # Set up the main build environment.
 203 #
 204 ########################################################################
 205
 206 # export TERM so that clang reports errors in color
 207 use_vars = set([ 'AS', 'AR', 'CC', 'CXX', 'HOME', 'LD_LIBRARY_PATH',
 208                  'LIBRARY_PATH', 'PATH', 'PKG_CONFIG_PATH', 'PROTOC',
 209                  'PYTHONPATH', 'RANLIB', 'SWIG', 'TERM' ])
 210
 211 use_prefixes = [
 212     "CCACHE_",         # ccache (caching compiler wrapper) configuration
 213     "CCC_",            # clang static analyzer configuration
 214     "DISTCC_",         # distcc (distributed compiler wrapper) configuration
 215     "INCLUDE_SERVER_", # distcc pump server settings
 216     "M5",              # M5 configuration (e.g., path to kernels)
 217     ]
 218
 219 use_env = {}
 220 for key,val in sorted(os.environ.iteritems()):
 221     if key in use_vars or \
 222             any([key.startswith(prefix) for prefix in use_prefixes]):
 223         use_env[key] = val
 224
 225 # Tell scons to avoid implicit command dependencies to avoid issues
 226 # with the param wrappes being compiled twice (see
 227 # http://scons.tigris.org/issues/show_bug.cgi?id=2811)
 228 main = Environment(ENV=use_env, IMPLICIT_COMMAND_DEPENDENCIES=0)
 229 main.Decider('MD5-timestamp')
 230 main.root = Dir(".")         # The current directory (where this file lives).
 231 main.srcdir = Dir("src")     # The source directory
 232
 233 main_dict_keys = main.Dictionary().keys()
 234
 235 # Check that we have a C/C++ compiler
 236 if not ('CC' in main_dict_keys and 'CXX' in main_dict_keys):
 237     print "No C++ compiler installed (package g++ on Ubuntu and RedHat)"
 238     Exit(1)
 239
 240 # Check that swig is present
 241 if not 'SWIG' in main_dict_keys:
 242     print "swig is not installed (package swig on Ubuntu and RedHat)"
 243     Exit(1)
 244
 245 # add useful python code PYTHONPATH so it can be used by subprocesses
 246 # as well
 247 main.AppendENVPath('PYTHONPATH', extra_python_paths)
 248
 249 ########################################################################
 250 #
 251 # Mercurial Stuff.
 252 #
 253 # If the gem5 directory is a mercurial repository, we should do some
 254 # extra things.
 255 #
 256 ########################################################################
 257
 258 hgdir = main.root.Dir(".hg")
 259
 260 mercurial_style_message = """
 261 You're missing the gem5 style hook, which automatically checks your code
 262 against the gem5 style rules on hg commit and qrefresh commands.  This
 263 script will now install the hook in your .hg/hgrc file.
 264 Press enter to continue, or ctrl-c to abort: """
 265
 266 mercurial_style_hook = """
 267 # The following lines were automatically added by gem5/SConstruct
 268 # to provide the gem5 style-checking hooks
 269 [extensions]
 270 style = %s/util/style.py
 271
 272 [hooks]
 273 pretxncommit.style = python:style.check_style
 274 pre-qrefresh.style = python:style.check_style
 275 # End of SConstruct additions
 276
 277 """ % (main.root.abspath)
 278
 279 mercurial_lib_not_found = """
 280 Mercurial libraries cannot be found, ignoring style hook.  If
 281 you are a gem5 developer, please fix this and run the style
 282 hook. It is important.
 283 """
 284
 285 # Check for style hook and prompt for installation if it's not there.
 286 # Skip this if --ignore-style was specified, there's no .hg dir to
 287 # install a hook in, or there's no interactive terminal to prompt.
 288 if not GetOption('ignore_style') and hgdir.exists() and sys.stdin.isatty():
 289     style_hook = True
 290     try:
 291         from mercurial import ui
 292         ui = ui.ui()
 293         ui.readconfig(hgdir.File('hgrc').abspath)
 294         style_hook = ui.config('hooks', 'pretxncommit.style', None) and \
 295                      ui.config('hooks', 'pre-qrefresh.style', None)
 296     except ImportError:
 297         print mercurial_lib_not_found
 298
 299     if not style_hook:
 300         print mercurial_style_message,
 301         # continue unless user does ctrl-c/ctrl-d etc.
 302         try:
 303             raw_input()
 304         except:
 305             print "Input exception, exiting scons.\n"
 306             sys.exit(1)
 307         hgrc_path = '%s/.hg/hgrc' % main.root.abspath
 308         print "Adding style hook to", hgrc_path, "\n"
 309         try:
 310             hgrc = open(hgrc_path, 'a')
 311             hgrc.write(mercurial_style_hook)
 312             hgrc.close()
 313         except:
 314             print "Error updating", hgrc_path
 315             sys.exit(1)
 316
 317
 318 ###################################################
 319 #
 320 # Figure out which configurations to set up based on the path(s) of
 321 # the target(s).
 322 #
 323 ###################################################
 324
 325 # Find default configuration & binary.
 326 Default(environ.get('M5_DEFAULT_BINARY', 'build/ALPHA/gem5.debug'))
 327
 328 # helper function: find last occurrence of element in list
 329 def rfind(l, elt, offs = -1):
 330     for i in range(len(l)+offs, 0, -1):
 331         if l[i] == elt:
 332             return i
 333     raise ValueError, "element not found"
 334
 335 # Take a list of paths (or SCons Nodes) and return a list with all
 336 # paths made absolute and ~-expanded.  Paths will be interpreted
 337 # relative to the launch directory unless a different root is provided
 338 def makePathListAbsolute(path_list, root=GetLaunchDir()):
 339     return [abspath(joinpath(root, expanduser(str(p))))
 340             for p in path_list]
 341
 342 # Each target must have 'build' in the interior of the path; the
 343 # directory below this will determine the build parameters.  For
 344 # example, for target 'foo/bar/build/ALPHA_SE/arch/alpha/blah.do' we
 345 # recognize that ALPHA_SE specifies the configuration because it
 346 # follow 'build' in the build path.
 347
 348 # The funky assignment to "[:]" is needed to replace the list contents
 349 # in place rather than reassign the symbol to a new list, which
 350 # doesn't work (obviously!).
 351 BUILD_TARGETS[:] = makePathListAbsolute(BUILD_TARGETS)
 352
 353 # Generate a list of the unique build roots and configs that the
 354 # collected targets reference.
 355 variant_paths = []
 356 build_root = None
 357 for t in BUILD_TARGETS:
 358     path_dirs = t.split('/')
 359     try:
 360         build_top = rfind(path_dirs, 'build', -2)
 361     except:
 362         print "Error: no non-leaf 'build' dir found on target path", t
 363         Exit(1)
 364     this_build_root = joinpath('/',*path_dirs[:build_top+1])
 365     if not build_root:
 366         build_root = this_build_root
 367     else:
 368         if this_build_root != build_root:
 369             print "Error: build targets not under same build root\n"\
 370                   "  %s\n  %s" % (build_root, this_build_root)
 371             Exit(1)
 372     variant_path = joinpath('/',*path_dirs[:build_top+2])
 373     if variant_path not in variant_paths:
 374         variant_paths.append(variant_path)
 375
 376 # Make sure build_root exists (might not if this is the first build there)
 377 if not isdir(build_root):
 378     mkdir(build_root)
 379 main['BUILDROOT'] = build_root
 380
 381 Export('main')
 382
 383 main.SConsignFile(joinpath(build_root, "sconsign"))
 384
 385 # Default duplicate option is to use hard links, but this messes up
 386 # when you use emacs to edit a file in the target dir, as emacs moves
 387 # file to file~ then copies to file, breaking the link.  Symbolic
 388 # (soft) links work better.
 389 main.SetOption('duplicate', 'soft-copy')
 390
 391 #
 392 # Set up global sticky variables... these are common to an entire build
 393 # tree (not specific to a particular build like ALPHA_SE)
 394 #
 395
 396 global_vars_file = joinpath(build_root, 'variables.global')
 397
 398 global_vars = Variables(global_vars_file, args=ARGUMENTS)
 399
 400 global_vars.AddVariables(
 401     ('CC', 'C compiler', environ.get('CC', main['CC'])),
 402     ('CXX', 'C++ compiler', environ.get('CXX', main['CXX'])),
 403     ('SWIG', 'SWIG tool', environ.get('SWIG', main['SWIG'])),
 404     ('PROTOC', 'protoc tool', environ.get('PROTOC', 'protoc')),
 405     ('BATCH', 'Use batch pool for build and tests', False),
 406     ('BATCH_CMD', 'Batch pool submission command name', 'qdo'),
 407     ('M5_BUILD_CACHE', 'Cache built objects in this directory', False),
 408     ('EXTRAS', 'Add extra directories to the compilation', '')
 409     )
 410
 411 # Update main environment with values from ARGUMENTS & global_vars_file
 412 global_vars.Update(main)
 413 help_texts["global_vars"] += global_vars.GenerateHelpText(main)
 414
 415 # Save sticky variable settings back to current variables file
 416 global_vars.Save(global_vars_file, main)
 417
 418 # Parse EXTRAS variable to build list of all directories where we're
 419 # look for sources etc.  This list is exported as extras_dir_list.
 420 base_dir = main.srcdir.abspath
 421 if main['EXTRAS']:
 422     extras_dir_list = makePathListAbsolute(main['EXTRAS'].split(':'))
 423 else:
 424     extras_dir_list = []
 425
 426 Export('base_dir')
 427 Export('extras_dir_list')
 428
 429 # the ext directory should be on the #includes path
 430 main.Append(CPPPATH=[Dir('ext')])
 431
 432 def strip_build_path(path, env):
 433     path = str(path)
 434     variant_base = env['BUILDROOT'] + os.path.sep
 435     if path.startswith(variant_base):
 436         path = path[len(variant_base):]
 437     elif path.startswith('build/'):
 438         path = path[6:]
 439     return path
 440
 441 # Generate a string of the form:
 442 #   common/path/prefix/src1, src2 -> tgt1, tgt2
 443 # to print while building.
 444 class Transform(object):
 445     # all specific color settings should be here and nowhere else
 446     tool_color = termcap.Normal
 447     pfx_color = termcap.Yellow
 448     srcs_color = termcap.Yellow + termcap.Bold
 449     arrow_color = termcap.Blue + termcap.Bold
 450     tgts_color = termcap.Yellow + termcap.Bold
 451
 452     def __init__(self, tool, max_sources=99):
 453         self.format = self.tool_color + (" [%8s] " % tool) \
 454                       + self.pfx_color + "%s" \
 455                       + self.srcs_color + "%s" \
 456                       + self.arrow_color + " -> " \
 457                       + self.tgts_color + "%s" \
 458                       + termcap.Normal
 459         self.max_sources = max_sources
 460
 461     def __call__(self, target, source, env, for_signature=None):
 462         # truncate source list according to max_sources param
 463         source = source[0:self.max_sources]
 464         def strip(f):
 465             return strip_build_path(str(f), env)
 466         if len(source) > 0:
 467             srcs = map(strip, source)
 468         else:
 469             srcs = ['']
 470         tgts = map(strip, target)
 471         # surprisingly, os.path.commonprefix is a dumb char-by-char string
 472         # operation that has nothing to do with paths.
 473         com_pfx = os.path.commonprefix(srcs + tgts)
 474         com_pfx_len = len(com_pfx)
 475         if com_pfx:
 476             # do some cleanup and sanity checking on common prefix
 477             if com_pfx[-1] == ".":
 478                 # prefix matches all but file extension: ok
 479                 # back up one to change 'foo.cc -> o' to 'foo.cc -> .o'
 480                 com_pfx = com_pfx[0:-1]
 481             elif com_pfx[-1] == "/":
 482                 # common prefix is directory path: OK
 483                 pass
 484             else:
 485                 src0_len = len(srcs[0])
 486                 tgt0_len = len(tgts[0])
 487                 if src0_len == com_pfx_len:
 488                     # source is a substring of target, OK
 489                     pass
 490                 elif tgt0_len == com_pfx_len:
 491                     # target is a substring of source, need to back up to
 492                     # avoid empty string on RHS of arrow
 493                     sep_idx = com_pfx.rfind(".")
 494                     if sep_idx != -1:
 495                         com_pfx = com_pfx[0:sep_idx]
 496                     else:
 497                         com_pfx = ''
 498                 elif src0_len > com_pfx_len and srcs[0][com_pfx_len] == ".":
 499                     # still splitting at file extension: ok
 500                     pass
 501                 else:
 502                     # probably a fluke; ignore it
 503                     com_pfx = ''
 504         # recalculate length in case com_pfx was modified
 505         com_pfx_len = len(com_pfx)
 506         def fmt(files):
 507             f = map(lambda s: s[com_pfx_len:], files)
 508             return ', '.join(f)
 509         return self.format % (com_pfx, fmt(srcs), fmt(tgts))
 510
 511 Export('Transform')
 512
 513 # enable the regression script to use the termcap
 514 main['TERMCAP'] = termcap
 515
 516 if GetOption('verbose'):
 517     def MakeAction(action, string, *args, **kwargs):
 518         return Action(action, *args, **kwargs)
 519 else:
 520     MakeAction = Action
 521     main['CCCOMSTR']        = Transform("CC")
 522     main['CXXCOMSTR']       = Transform("CXX")
 523     main['ASCOMSTR']        = Transform("AS")
 524     main['SWIGCOMSTR']      = Transform("SWIG")
 525     main['ARCOMSTR']        = Transform("AR", 0)
 526     main['LINKCOMSTR']      = Transform("LINK", 0)
 527     main['RANLIBCOMSTR']    = Transform("RANLIB", 0)
 528     main['M4COMSTR']        = Transform("M4")
 529     main['SHCCCOMSTR']      = Transform("SHCC")
 530     main['SHCXXCOMSTR']     = Transform("SHCXX")
 531 Export('MakeAction')
 532
 533 # Initialize the Link-Time Optimization (LTO) flags
 534 main['LTO_CCFLAGS'] = []
 535 main['LTO_LDFLAGS'] = []
 536
 537 # According to the readme, tcmalloc works best if the compiler doesn't
 538 # assume that we're using the builtin malloc and friends. These flags
 539 # are compiler-specific, so we need to set them after we detect which
 540 # compiler we're using.
 541 main['TCMALLOC_CCFLAGS'] = []
 542
 543 CXX_version = readCommand([main['CXX'],'--version'], exception=False)
 544 CXX_V = readCommand([main['CXX'],'-V'], exception=False)
 545
 546 main['GCC'] = CXX_version and CXX_version.find('g++') >= 0
 547 main['CLANG'] = CXX_version and CXX_version.find('clang') >= 0
 548 if main['GCC'] + main['CLANG'] > 1:
 549     print 'Error: How can we have two at the same time?'
 550     Exit(1)
 551
 552 # Set up default C++ compiler flags
 553 if main['GCC'] or main['CLANG']:
 554     # As gcc and clang share many flags, do the common parts here
 555     main.Append(CCFLAGS=['-pipe'])
 556     main.Append(CCFLAGS=['-fno-strict-aliasing'])
 557     # Enable -Wall and then disable the few warnings that we
 558     # consistently violate
 559     main.Append(CCFLAGS=['-Wall', '-Wno-sign-compare', '-Wundef'])
 560     # We always compile using C++11
 561     main.Append(CXXFLAGS=['-std=c++11'])
 562     # Add selected sanity checks from -Wextra
 563     main.Append(CXXFLAGS=['-Wmissing-field-initializers',
 564                           '-Woverloaded-virtual'])
 565 else:
 566     print termcap.Yellow + termcap.Bold + 'Error' + termcap.Normal,
 567     print "Don't know what compiler options to use for your compiler."
 568     print termcap.Yellow + '       compiler:' + termcap.Normal, main['CXX']
 569     print termcap.Yellow + '       version:' + termcap.Normal,
 570     if not CXX_version:
 571         print termcap.Yellow + termcap.Bold + "COMMAND NOT FOUND!" +\
 572                termcap.Normal
 573     else:
 574         print CXX_version.replace('\n', '<nl>')
 575     print "       If you're trying to use a compiler other than GCC"
 576     print "       or clang, there appears to be something wrong with your"
 577     print "       environment."
 578     print "       "
 579     print "       If you are trying to use a compiler other than those listed"
 580     print "       above you will need to ease fix SConstruct and "
 581     print "       src/SConscript to support that compiler."
 582     Exit(1)
 583
 584 if main['GCC']:
 585     # Check for a supported version of gcc. >= 4.7 is chosen for its
 586     # level of c++11 support. See
 587     # http://gcc.gnu.org/projects/cxx0x.html for details.
 588     gcc_version = readCommand([main['CXX'], '-dumpversion'], exception=False)
 589     if compareVersions(gcc_version, "4.7") < 0:
 590         print 'Error: gcc version 4.7 or newer required.'
 591         print '       Installed version:', gcc_version
 592         Exit(1)
 593
 594     main['GCC_VERSION'] = gcc_version
 595
 596     # gcc from version 4.8 and above generates "rep; ret" instructions
 597     # to avoid performance penalties on certain AMD chips. Older
 598     # assemblers detect this as an error, "Error: expecting string
 599     # instruction after `rep'"
 600     if compareVersions(gcc_version, "4.8") > 0:
 601         as_version_raw = readCommand([main['AS'], '-v', '/dev/null'],
 602                                      exception=False).split()
 603
 604         # version strings may contain extra distro-specific
 605         # qualifiers, so play it safe and keep only what comes before
 606         # the first hyphen
 607         as_version = as_version_raw[-1].split('-')[0] if as_version_raw \
 608             else None
 609
 610         if not as_version or compareVersions(as_version, "2.23") < 0:
 611             print termcap.Yellow + termcap.Bold + \
 612                 'Warning: This combination of gcc and binutils have' + \
 613                 ' known incompatibilities.\n' + \
 614                 '         If you encounter build problems, please update ' + \
 615                 'binutils to 2.23.' + \
 616                 termcap.Normal
 617
 618     # Make sure we warn if the user has requested to compile with the
 619     # Undefined Benahvior Sanitizer and this version of gcc does not
 620     # support it.
 621     if GetOption('with_ubsan') and \
 622             compareVersions(gcc_version, '4.9') < 0:
 623         print termcap.Yellow + termcap.Bold + \
 624             'Warning: UBSan is only supported using gcc 4.9 and later.' + \
 625             termcap.Normal
 626
 627     # Add the appropriate Link-Time Optimization (LTO) flags
 628     # unless LTO is explicitly turned off. Note that these flags
 629     # are only used by the fast target.
 630     if not GetOption('no_lto'):
 631         # Pass the LTO flag when compiling to produce GIMPLE
 632         # output, we merely create the flags here and only append
 633         # them later
 634         main['LTO_CCFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
 635
 636         # Use the same amount of jobs for LTO as we are running
 637         # scons with
 638         main['LTO_LDFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
 639
 640     main.Append(TCMALLOC_CCFLAGS=['-fno-builtin-malloc', '-fno-builtin-calloc',
 641                                   '-fno-builtin-realloc', '-fno-builtin-free'])
 642
 643 elif main['CLANG']:
 644     # Check for a supported version of clang, >= 3.1 is needed to
 645     # support similar features as gcc 4.7. See
 646     # http://clang.llvm.org/cxx_status.html for details
 647     clang_version_re = re.compile(".* version (\d+\.\d+)")
 648     clang_version_match = clang_version_re.search(CXX_version)
 649     if (clang_version_match):
 650         clang_version = clang_version_match.groups()[0]
 651         if compareVersions(clang_version, "3.1") < 0:
 652             print 'Error: clang version 3.1 or newer required.'
 653             print '       Installed version:', clang_version
 654             Exit(1)
 655     else:
 656         print 'Error: Unable to determine clang version.'
 657         Exit(1)
 658
 659     # clang has a few additional warnings that we disable,
 660     # tautological comparisons are allowed due to unsigned integers
 661     # being compared to constants that happen to be 0, and extraneous
 662     # parantheses are allowed due to Ruby's printing of the AST,
 663     # finally self assignments are allowed as the generated CPU code
 664     # is relying on this
 665     main.Append(CCFLAGS=['-Wno-tautological-compare',
 666                          '-Wno-parentheses',
 667                          '-Wno-self-assign',
 668                          # Some versions of libstdc++ (4.8?) seem to
 669                          # use struct hash and class hash
 670                          # interchangeably.
 671                          '-Wno-mismatched-tags',
 672                          ])
 673
 674     main.Append(TCMALLOC_CCFLAGS=['-fno-builtin'])
 675
 676     # On Mac OS X/Darwin we need to also use libc++ (part of XCode) as
 677     # opposed to libstdc++, as the later is dated.
 678     if sys.platform == "darwin":
 679         main.Append(CXXFLAGS=['-stdlib=libc++'])
 680         main.Append(LIBS=['c++'])
 681
 682 else:
 683     print termcap.Yellow + termcap.Bold + 'Error' + termcap.Normal,
 684     print "Don't know what compiler options to use for your compiler."
 685     print termcap.Yellow + '       compiler:' + termcap.Normal, main['CXX']
 686     print termcap.Yellow + '       version:' + termcap.Normal,
 687     if not CXX_version:
 688         print termcap.Yellow + termcap.Bold + "COMMAND NOT FOUND!" +\
 689                termcap.Normal
 690     else:
 691         print CXX_version.replace('\n', '<nl>')
 692     print "       If you're trying to use a compiler other than GCC"
 693     print "       or clang, there appears to be something wrong with your"
 694     print "       environment."
 695     print "       "
 696     print "       If you are trying to use a compiler other than those listed"
 697     print "       above you will need to ease fix SConstruct and "
 698     print "       src/SConscript to support that compiler."
 699     Exit(1)
 700
 701 # Set up common yacc/bison flags (needed for Ruby)
 702 main['YACCFLAGS'] = '-d'
 703 main['YACCHXXFILESUFFIX'] = '.hh'
 704
 705 # Do this after we save setting back, or else we'll tack on an
 706 # extra 'qdo' every time we run scons.
 707 if main['BATCH']:
 708     main['CC']     = main['BATCH_CMD'] + ' ' + main['CC']
 709     main['CXX']    = main['BATCH_CMD'] + ' ' + main['CXX']
 710     main['AS']     = main['BATCH_CMD'] + ' ' + main['AS']
 711     main['AR']     = main['BATCH_CMD'] + ' ' + main['AR']
 712     main['RANLIB'] = main['BATCH_CMD'] + ' ' + main['RANLIB']
 713
 714 if sys.platform == 'cygwin':
 715     # cygwin has some header file issues...
 716     main.Append(CCFLAGS=["-Wno-uninitialized"])
 717
 718 # Check for the protobuf compiler
 719 protoc_version = readCommand([main['PROTOC'], '--version'],
 720                              exception='').split()
 721
 722 # First two words should be "libprotoc x.y.z"
 723 if len(protoc_version) < 2 or protoc_version[0] != 'libprotoc':
 724     print termcap.Yellow + termcap.Bold + \
 725         'Warning: Protocol buffer compiler (protoc) not found.\n' + \
 726         '         Please install protobuf-compiler for tracing support.' + \
 727         termcap.Normal
 728     main['PROTOC'] = False
 729 else:
 730     # Based on the availability of the compress stream wrappers,
 731     # require 2.1.0
 732     min_protoc_version = '2.1.0'
 733     if compareVersions(protoc_version[1], min_protoc_version) < 0:
 734         print termcap.Yellow + termcap.Bold + \
 735             'Warning: protoc version', min_protoc_version, \
 736             'or newer required.\n' + \
 737             '         Installed version:', protoc_version[1], \
 738             termcap.Normal
 739         main['PROTOC'] = False
 740     else:
 741         # Attempt to determine the appropriate include path and
 742         # library path using pkg-config, that means we also need to
 743         # check for pkg-config. Note that it is possible to use
 744         # protobuf without the involvement of pkg-config. Later on we
 745         # check go a library config check and at that point the test
 746         # will fail if libprotobuf cannot be found.
 747         if readCommand(['pkg-config', '--version'], exception=''):
 748             try:
 749                 # Attempt to establish what linking flags to add for protobuf
 750                 # using pkg-config
 751                 main.ParseConfig('pkg-config --cflags --libs-only-L protobuf')
 752             except:
 753                 print termcap.Yellow + termcap.Bold + \
 754                     'Warning: pkg-config could not get protobuf flags.' + \
 755                     termcap.Normal
 756
 757 # Check for SWIG
 758 if not main.has_key('SWIG'):
 759     print 'Error: SWIG utility not found.'
 760     print '       Please install (see http://www.swig.org) and retry.'
 761     Exit(1)
 762
 763 # Check for appropriate SWIG version
 764 swig_version = readCommand([main['SWIG'], '-version'], exception='').split()
 765 # First 3 words should be "SWIG Version x.y.z"
 766 if len(swig_version) < 3 or \
 767         swig_version[0] != 'SWIG' or swig_version[1] != 'Version':
 768     print 'Error determining SWIG version.'
 769     Exit(1)
 770
 771 min_swig_version = '2.0.4'
 772 if compareVersions(swig_version[2], min_swig_version) < 0:
 773     print 'Error: SWIG version', min_swig_version, 'or newer required.'
 774     print '       Installed version:', swig_version[2]
 775     Exit(1)
 776
 777 # Check for known incompatibilities. The standard library shipped with
 778 # gcc >= 4.9 does not play well with swig versions prior to 3.0
 779 if main['GCC'] and compareVersions(gcc_version, '4.9') >= 0 and \
 780         compareVersions(swig_version[2], '3.0') < 0:
 781     print termcap.Yellow + termcap.Bold + \
 782         'Warning: This combination of gcc and swig have' + \
 783         ' known incompatibilities.\n' + \
 784         '         If you encounter build problems, please update ' + \
 785         'swig to 3.0 or later.' + \
 786         termcap.Normal
 787
 788 # Set up SWIG flags & scanner
 789 swig_flags=Split('-c++ -python -modern -templatereduce $_CPPINCFLAGS')
 790 main.Append(SWIGFLAGS=swig_flags)
 791
 792 # Check for 'timeout' from GNU coreutils. If present, regressions will
 793 # be run with a time limit. We require version 8.13 since we rely on
 794 # support for the '--foreground' option.
 795 timeout_lines = readCommand(['timeout', '--version'],
 796                             exception='').splitlines()
 797 # Get the first line and tokenize it
 798 timeout_version = timeout_lines[0].split() if timeout_lines else []
 799 main['TIMEOUT'] =  timeout_version and \
 800     compareVersions(timeout_version[-1], '8.13') >= 0
 801
 802 # filter out all existing swig scanners, they mess up the dependency
 803 # stuff for some reason
 804 scanners = []
 805 for scanner in main['SCANNERS']:
 806     skeys = scanner.skeys
 807     if skeys == '.i':
 808         continue
 809
 810     if isinstance(skeys, (list, tuple)) and '.i' in skeys:
 811         continue
 812
 813     scanners.append(scanner)
 814
 815 # add the new swig scanner that we like better
 816 from SCons.Scanner import ClassicCPP as CPPScanner
 817 swig_inc_re = '^[ \t]*[%,#][ \t]*(?:include|import)[ \t]*(<|")([^>"]+)(>|")'
 818 scanners.append(CPPScanner("SwigScan", [ ".i" ], "CPPPATH", swig_inc_re))
 819
 820 # replace the scanners list that has what we want
 821 main['SCANNERS'] = scanners
 822
 823 # Add a custom Check function to test for structure members.
 824 def CheckMember(context, include, decl, member, include_quotes="<>"):
 825     context.Message("Checking for member %s in %s..." %
 826                     (member, decl))
 827     text = """
 828 #include %(header)s
 829 int main(){
 830   %(decl)s test;
 831   (void)test.%(member)s;
 832   return 0;
 833 };
 834 """ % { "header" : include_quotes[0] + include + include_quotes[1],
 835         "decl" : decl,
 836         "member" : member,
 837         }
 838
 839     ret = context.TryCompile(text, extension=".cc")
 840     context.Result(ret)
 841     return ret
 842
 843 # Platform-specific configuration.  Note again that we assume that all
 844 # builds under a given build root run on the same host platform.
 845 conf = Configure(main,
 846                  conf_dir = joinpath(build_root, '.scons_config'),
 847                  log_file = joinpath(build_root, 'scons_config.log'),
 848                  custom_tests = {
 849         'CheckMember' : CheckMember,
 850         })
 851
 852 # Check if we should compile a 64 bit binary on Mac OS X/Darwin
 853 try:
 854     import platform
 855     uname = platform.uname()
 856     if uname[0] == 'Darwin' and compareVersions(uname[2], '9.0.0') >= 0:
 857         if int(readCommand('sysctl -n hw.cpu64bit_capable')[0]):
 858             main.Append(CCFLAGS=['-arch', 'x86_64'])
 859             main.Append(CFLAGS=['-arch', 'x86_64'])
 860             main.Append(LINKFLAGS=['-arch', 'x86_64'])
 861             main.Append(ASFLAGS=['-arch', 'x86_64'])
 862 except:
 863     pass
 864
 865 # Recent versions of scons substitute a "Null" object for Configure()
 866 # when configuration isn't necessary, e.g., if the "--help" option is
 867 # present.  Unfortuantely this Null object always returns false,
 868 # breaking all our configuration checks.  We replace it with our own
 869 # more optimistic null object that returns True instead.
 870 if not conf:
 871     def NullCheck(*args, **kwargs):
 872         return True
 873
 874     class NullConf:
 875         def __init__(self, env):
 876             self.env = env
 877         def Finish(self):
 878             return self.env
 879         def __getattr__(self, mname):
 880             return NullCheck
 881
 882     conf = NullConf(main)
 883
 884 # Cache build files in the supplied directory.
 885 if main['M5_BUILD_CACHE']:
 886     print 'Using build cache located at', main['M5_BUILD_CACHE']
 887     CacheDir(main['M5_BUILD_CACHE'])
 888
 889 if not GetOption('without_python'):
 890     # Find Python include and library directories for embedding the
 891     # interpreter. We rely on python-config to resolve the appropriate
 892     # includes and linker flags. ParseConfig does not seem to understand
 893     # the more exotic linker flags such as -Xlinker and -export-dynamic so
 894     # we add them explicitly below. If you want to link in an alternate
 895     # version of python, see above for instructions on how to invoke
 896     # scons with the appropriate PATH set.
 897     #
 898     # First we check if python2-config exists, else we use python-config
 899     python_config = readCommand(['which', 'python2-config'],
 900                                 exception='').strip()
 901     if not os.path.exists(python_config):
 902         python_config = readCommand(['which', 'python-config'],
 903                                     exception='').strip()
 904     py_includes = readCommand([python_config, '--includes'],
 905                               exception='').split()
 906     # Strip the -I from the include folders before adding them to the
 907     # CPPPATH
 908     main.Append(CPPPATH=map(lambda inc: inc[2:], py_includes))
 909
 910     # Read the linker flags and split them into libraries and other link
 911     # flags. The libraries are added later through the call the CheckLib.
 912     py_ld_flags = readCommand([python_config, '--ldflags'],
 913         exception='').split()
 914     py_libs = []
 915     for lib in py_ld_flags:
 916          if not lib.startswith('-l'):
 917              main.Append(LINKFLAGS=[lib])
 918          else:
 919              lib = lib[2:]
 920              if lib not in py_libs:
 921                  py_libs.append(lib)
 922
 923     # verify that this stuff works
 924     if not conf.CheckHeader('Python.h', '<>'):
 925         print "Error: can't find Python.h header in", py_includes
 926         print "Install Python headers (package python-dev on Ubuntu and RedHat)"
 927         Exit(1)
 928
 929     for lib in py_libs:
 930         if not conf.CheckLib(lib):
 931             print "Error: can't find library %s required by python" % lib
 932             Exit(1)
 933
 934 # On Solaris you need to use libsocket for socket ops
 935 if not conf.CheckLibWithHeader(None, 'sys/socket.h', 'C++', 'accept(0,0,0);'):
 936    if not conf.CheckLibWithHeader('socket', 'sys/socket.h', 'C++', 'accept(0,0,0);'):
 937        print "Can't find library with socket calls (e.g. accept())"
 938        Exit(1)
 939
 940 # Check for zlib.  If the check passes, libz will be automatically
 941 # added to the LIBS environment variable.
 942 if not conf.CheckLibWithHeader('z', 'zlib.h', 'C++','zlibVersion();'):
 943     print 'Error: did not find needed zlib compression library '\
 944           'and/or zlib.h header file.'
 945     print '       Please install zlib and try again.'
 946     Exit(1)
 947
 948 # If we have the protobuf compiler, also make sure we have the
 949 # development libraries. If the check passes, libprotobuf will be
 950 # automatically added to the LIBS environment variable. After
 951 # this, we can use the HAVE_PROTOBUF flag to determine if we have
 952 # got both protoc and libprotobuf available.
 953 main['HAVE_PROTOBUF'] = main['PROTOC'] and \
 954     conf.CheckLibWithHeader('protobuf', 'google/protobuf/message.h',
 955                             'C++', 'GOOGLE_PROTOBUF_VERIFY_VERSION;')
 956
 957 # If we have the compiler but not the library, print another warning.
 958 if main['PROTOC'] and not main['HAVE_PROTOBUF']:
 959     print termcap.Yellow + termcap.Bold + \
 960         'Warning: did not find protocol buffer library and/or headers.\n' + \
 961     '       Please install libprotobuf-dev for tracing support.' + \
 962     termcap.Normal
 963
 964 # Check for librt.
 965 have_posix_clock = \
 966     conf.CheckLibWithHeader(None, 'time.h', 'C',
 967                             'clock_nanosleep(0,0,NULL,NULL);') or \
 968     conf.CheckLibWithHeader('rt', 'time.h', 'C',
 969                             'clock_nanosleep(0,0,NULL,NULL);')
 970
 971 have_posix_timers = \
 972     conf.CheckLibWithHeader([None, 'rt'], [ 'time.h', 'signal.h' ], 'C',
 973                             'timer_create(CLOCK_MONOTONIC, NULL, NULL);')
 974
 975 if not GetOption('without_tcmalloc'):
 976     if conf.CheckLib('tcmalloc'):
 977         main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
 978     elif conf.CheckLib('tcmalloc_minimal'):
 979         main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
 980     else:
 981         print termcap.Yellow + termcap.Bold + \
 982               "You can get a 12% performance improvement by "\
 983               "installing tcmalloc (libgoogle-perftools-dev package "\
 984               "on Ubuntu or RedHat)." + termcap.Normal
 985
 986
 987 # Detect back trace implementations. The last implementation in the
 988 # list will be used by default.
 989 backtrace_impls = [ "none" ]
 990
 991 if conf.CheckLibWithHeader(None, 'execinfo.h', 'C',
 992                            'backtrace_symbols_fd((void*)0, 0, 0);'):
 993     backtrace_impls.append("glibc")
 994
 995 if backtrace_impls[-1] == "none":
 996     default_backtrace_impl = "none"
 997     print termcap.Yellow + termcap.Bold + \
 998         "No suitable back trace implementation found." + \
 999         termcap.Normal
1000
1001 if not have_posix_clock:
1002     print "Can't find library for POSIX clocks."
1003
1004 # Check for <fenv.h> (C99 FP environment control)
1005 have_fenv = conf.CheckHeader('fenv.h', '<>')
1006 if not have_fenv:
1007     print "Warning: Header file <fenv.h> not found."
1008     print "         This host has no IEEE FP rounding mode control."
1009
1010 # Check if we should enable KVM-based hardware virtualization. The API
1011 # we rely on exists since version 2.6.36 of the kernel, but somehow
1012 # the KVM_API_VERSION does not reflect the change. We test for one of
1013 # the types as a fall back.
1014 have_kvm = conf.CheckHeader('linux/kvm.h', '<>')
1015 if not have_kvm:
1016     print "Info: Compatible header file <linux/kvm.h> not found, " \
1017         "disabling KVM support."
1018
1019 # x86 needs support for xsave. We test for the structure here since we
1020 # won't be able to run new tests by the time we know which ISA we're
1021 # targeting.
1022 have_kvm_xsave = conf.CheckTypeSize('struct kvm_xsave',
1023                                     '#include <linux/kvm.h>') != 0
1024
1025 # Check if the requested target ISA is compatible with the host
1026 def is_isa_kvm_compatible(isa):
1027     try:
1028         import platform
1029         host_isa = platform.machine()
1030     except:
1031         print "Warning: Failed to determine host ISA."
1032         return False
1033
1034     if not have_posix_timers:
1035         print "Warning: Can not enable KVM, host seems to lack support " \
1036             "for POSIX timers"
1037         return False
1038
1039     if isa == "arm":
1040         return host_isa in ( "armv7l", "aarch64" )
1041     elif isa == "x86":
1042         if host_isa != "x86_64":
1043             return False
1044
1045         if not have_kvm_xsave:
1046             print "KVM on x86 requires xsave support in kernel headers."
1047             return False
1048
1049         return True
1050     else:
1051         return False
1052
1053
1054 # Check if the exclude_host attribute is available. We want this to
1055 # get accurate instruction counts in KVM.
1056 main['HAVE_PERF_ATTR_EXCLUDE_HOST'] = conf.CheckMember(
1057     'linux/perf_event.h', 'struct perf_event_attr', 'exclude_host')
1058
1059
1060 ######################################################################
1061 #
1062 # Finish the configuration
1063 #
1064 main = conf.Finish()
1065
1066 ######################################################################
1067 #
1068 # Collect all non-global variables
1069 #
1070
1071 # Define the universe of supported ISAs
1072 all_isa_list = [ ]
1073 Export('all_isa_list')
1074
1075 class CpuModel(object):
1076     '''The CpuModel class encapsulates everything the ISA parser needs to
1077     know about a particular CPU model.'''
1078
1079     # Dict of available CPU model objects.  Accessible as CpuModel.dict.
1080     dict = {}
1081
1082     # Constructor.  Automatically adds models to CpuModel.dict.
1083     def __init__(self, name, default=False):
1084         self.name = name           # name of model
1085
1086         # This cpu is enabled by default
1087         self.default = default
1088
1089         # Add self to dict
1090         if name in CpuModel.dict:
1091             raise AttributeError, "CpuModel '%s' already registered" % name
1092         CpuModel.dict[name] = self
1093
1094 Export('CpuModel')
1095
1096 # Sticky variables get saved in the variables file so they persist from
1097 # one invocation to the next (unless overridden, in which case the new
1098 # value becomes sticky).
1099 sticky_vars = Variables(args=ARGUMENTS)
1100 Export('sticky_vars')
1101
1102 # Sticky variables that should be exported
1103 export_vars = []
1104 Export('export_vars')
1105
1106 # For Ruby
1107 all_protocols = []
1108 Export('all_protocols')
1109 protocol_dirs = []
1110 Export('protocol_dirs')
1111 slicc_includes = []
1112 Export('slicc_includes')
1113
1114 # Walk the tree and execute all SConsopts scripts that wil add to the
1115 # above variables
1116 if GetOption('verbose'):
1117     print "Reading SConsopts"
1118 for bdir in [ base_dir ] + extras_dir_list:
1119     if not isdir(bdir):
1120         print "Error: directory '%s' does not exist" % bdir
1121         Exit(1)
1122     for root, dirs, files in os.walk(bdir):
1123         if 'SConsopts' in files:
1124             if GetOption('verbose'):
1125                 print "Reading", joinpath(root, 'SConsopts')
1126             SConscript(joinpath(root, 'SConsopts'))
1127
1128 all_isa_list.sort()
1129
1130 sticky_vars.AddVariables(
1131     EnumVariable('TARGET_ISA', 'Target ISA', 'alpha', all_isa_list),
1132     ListVariable('CPU_MODELS', 'CPU models',
1133                  sorted(n for n,m in CpuModel.dict.iteritems() if m.default),
1134                  sorted(CpuModel.dict.keys())),
1135     BoolVariable('EFENCE', 'Link with Electric Fence malloc debugger',
1136                  False),
1137     BoolVariable('SS_COMPATIBLE_FP',
1138                  'Make floating-point results compatible with SimpleScalar',
1139                  False),
1140     BoolVariable('USE_SSE2',
1141                  'Compile for SSE2 (-msse2) to get IEEE FP on x86 hosts',
1142                  False),
1143     BoolVariable('USE_POSIX_CLOCK', 'Use POSIX Clocks', have_posix_clock),
1144     BoolVariable('USE_FENV', 'Use <fenv.h> IEEE mode control', have_fenv),
1145     BoolVariable('CP_ANNOTATE', 'Enable critical path annotation capability', False),
1146     BoolVariable('USE_KVM', 'Enable hardware virtualized (KVM) CPU models', have_kvm),
1147     EnumVariable('PROTOCOL', 'Coherence protocol for Ruby', 'None',
1148                   all_protocols),
1149     EnumVariable('BACKTRACE_IMPL', 'Post-mortem dump implementation',
1150                  backtrace_impls[-1], backtrace_impls)
1151     )
1152
1153 # These variables get exported to #defines in config/*.hh (see src/SConscript).
1154 export_vars += ['USE_FENV', 'SS_COMPATIBLE_FP', 'TARGET_ISA', 'CP_ANNOTATE',
1155                 'USE_POSIX_CLOCK', 'USE_KVM', 'PROTOCOL', 'HAVE_PROTOBUF',
1156                 'HAVE_PERF_ATTR_EXCLUDE_HOST']
1157
1158 ###################################################
1159 #
1160 # Define a SCons builder for configuration flag headers.
1161 #
1162 ###################################################
1163
1164 # This function generates a config header file that #defines the
1165 # variable symbol to the current variable setting (0 or 1).  The source
1166 # operands are the name of the variable and a Value node containing the
1167 # value of the variable.
1168 def build_config_file(target, source, env):
1169     (variable, value) = [s.get_contents() for s in source]
1170     f = file(str(target[0]), 'w')
1171     print >> f, '#define', variable, value
1172     f.close()
1173     return None
1174
1175 # Combine the two functions into a scons Action object.
1176 config_action = MakeAction(build_config_file, Transform("CONFIG H", 2))
1177
1178 # The emitter munges the source & target node lists to reflect what
1179 # we're really doing.
1180 def config_emitter(target, source, env):
1181     # extract variable name from Builder arg
1182     variable = str(target[0])
1183     # True target is config header file
1184     target = joinpath('config', variable.lower() + '.hh')
1185     val = env[variable]
1186     if isinstance(val, bool):
1187         # Force value to 0/1
1188         val = int(val)
1189     elif isinstance(val, str):
1190         val = '"' + val + '"'
1191
1192     # Sources are variable name & value (packaged in SCons Value nodes)
1193     return ([target], [Value(variable), Value(val)])
1194
1195 config_builder = Builder(emitter = config_emitter, action = config_action)
1196
1197 main.Append(BUILDERS = { 'ConfigFile' : config_builder })
1198
1199 # libelf build is shared across all configs in the build root.
1200 main.SConscript('ext/libelf/SConscript',
1201                 variant_dir = joinpath(build_root, 'libelf'))
1202
1203 # iostream3 build is shared across all configs in the build root.
1204 main.SConscript('ext/iostream3/SConscript',
1205                 variant_dir = joinpath(build_root, 'iostream3'))
1206
1207 # libfdt build is shared across all configs in the build root.
1208 main.SConscript('ext/libfdt/SConscript',
1209                 variant_dir = joinpath(build_root, 'libfdt'))
1210
1211 # fputils build is shared across all configs in the build root.
1212 main.SConscript('ext/fputils/SConscript',
1213                 variant_dir = joinpath(build_root, 'fputils'))
1214
1215 # DRAMSim2 build is shared across all configs in the build root.
1216 main.SConscript('ext/dramsim2/SConscript',
1217                 variant_dir = joinpath(build_root, 'dramsim2'))
1218
1219 # DRAMPower build is shared across all configs in the build root.
1220 main.SConscript('ext/drampower/SConscript',
1221                 variant_dir = joinpath(build_root, 'drampower'))
1222
1223 # nomali build is shared across all configs in the build root.
1224 main.SConscript('ext/nomali/SConscript',
1225                 variant_dir = joinpath(build_root, 'nomali'))
1226
1227 ###################################################
1228 #
1229 # This function is used to set up a directory with switching headers
1230 #
1231 ###################################################
1232
1233 main['ALL_ISA_LIST'] = all_isa_list
1234 all_isa_deps = {}
1235 def make_switching_dir(dname, switch_headers, env):
1236     # Generate the header.  target[0] is the full path of the output
1237     # header to generate.  'source' is a dummy variable, since we get the
1238     # list of ISAs from env['ALL_ISA_LIST'].
1239     def gen_switch_hdr(target, source, env):
1240         fname = str(target[0])
1241         isa = env['TARGET_ISA'].lower()
1242         try:
1243             f = open(fname, 'w')
1244             print >>f, '#include "%s/%s/%s"' % (dname, isa, basename(fname))
1245             f.close()
1246         except IOError:
1247             print "Failed to create %s" % fname
1248             raise
1249
1250     # Build SCons Action object. 'varlist' specifies env vars that this
1251     # action depends on; when env['ALL_ISA_LIST'] changes these actions
1252     # should get re-executed.
1253     switch_hdr_action = MakeAction(gen_switch_hdr,
1254                           Transform("GENERATE"), varlist=['ALL_ISA_LIST'])
1255
1256     # Instantiate actions for each header
1257     for hdr in switch_headers:
1258         env.Command(hdr, [], switch_hdr_action)
1259
1260     isa_target = Dir('.').up().name.lower().replace('_', '-')
1261     env['PHONY_BASE'] = '#'+isa_target
1262     all_isa_deps[isa_target] = None
1263
1264 Export('make_switching_dir')
1265
1266 # all-isas -> all-deps -> all-environs -> all_targets
1267 main.Alias('#all-isas', [])
1268 main.Alias('#all-deps', '#all-isas')
1269
1270 # Dummy target to ensure all environments are created before telling
1271 # SCons what to actually make (the command line arguments).  We attach
1272 # them to the dependence graph after the environments are complete.
1273 ORIG_BUILD_TARGETS = list(BUILD_TARGETS) # force a copy; gets closure to work.
1274 def environsComplete(target, source, env):
1275     for t in ORIG_BUILD_TARGETS:
1276         main.Depends('#all-targets', t)
1277
1278 # Each build/* switching_dir attaches its *-environs target to #all-environs.
1279 main.Append(BUILDERS = {'CompleteEnvirons' :
1280                         Builder(action=MakeAction(environsComplete, None))})
1281 main.CompleteEnvirons('#all-environs', [])
1282
1283 def doNothing(**ignored): pass
1284 main.Append(BUILDERS = {'Dummy': Builder(action=MakeAction(doNothing, None))})
1285
1286 # The final target to which all the original targets ultimately get attached.
1287 main.Dummy('#all-targets', '#all-environs')
1288 BUILD_TARGETS[:] = ['#all-targets']
1289
1290 ###################################################
1291 #
1292 # Define build environments for selected configurations.
1293 #
1294 ###################################################
1295
1296 for variant_path in variant_paths:
1297     if not GetOption('silent'):
1298         print "Building in", variant_path
1299
1300     # Make a copy of the build-root environment to use for this config.
1301     env = main.Clone()
1302     env['BUILDDIR'] = variant_path
1303
1304     # variant_dir is the tail component of build path, and is used to
1305     # determine the build parameters (e.g., 'ALPHA_SE')
1306     (build_root, variant_dir) = splitpath(variant_path)
1307
1308     # Set env variables according to the build directory config.
1309     sticky_vars.files = []
1310     # Variables for $BUILD_ROOT/$VARIANT_DIR are stored in
1311     # $BUILD_ROOT/variables/$VARIANT_DIR so you can nuke
1312     # $BUILD_ROOT/$VARIANT_DIR without losing your variables settings.
1313     current_vars_file = joinpath(build_root, 'variables', variant_dir)
1314     if isfile(current_vars_file):
1315         sticky_vars.files.append(current_vars_file)
1316         if not GetOption('silent'):
1317             print "Using saved variables file %s" % current_vars_file
1318     else:
1319         # Build dir-specific variables file doesn't exist.
1320
1321         # Make sure the directory is there so we can create it later
1322         opt_dir = dirname(current_vars_file)
1323         if not isdir(opt_dir):
1324             mkdir(opt_dir)
1325
1326         # Get default build variables from source tree.  Variables are
1327         # normally determined by name of $VARIANT_DIR, but can be
1328         # overridden by '--default=' arg on command line.
1329         default = GetOption('default')
1330         opts_dir = joinpath(main.root.abspath, 'build_opts')
1331         if default:
1332             default_vars_files = [joinpath(build_root, 'variables', default),
1333                                   joinpath(opts_dir, default)]
1334         else:
1335             default_vars_files = [joinpath(opts_dir, variant_dir)]
1336         existing_files = filter(isfile, default_vars_files)
1337         if existing_files:
1338             default_vars_file = existing_files[0]
1339             sticky_vars.files.append(default_vars_file)
1340             print "Variables file %s not found,\n  using defaults in %s" \
1341                   % (current_vars_file, default_vars_file)
1342         else:
1343             print "Error: cannot find variables file %s or " \
1344                   "default file(s) %s" \
1345                   % (current_vars_file, ' or '.join(default_vars_files))
1346             Exit(1)
1347
1348     # Apply current variable settings to env
1349     sticky_vars.Update(env)
1350
1351     help_texts["local_vars"] += \
1352         "Build variables for %s:\n" % variant_dir \
1353                  + sticky_vars.GenerateHelpText(env)
1354
1355     # Process variable settings.
1356
1357     if not have_fenv and env['USE_FENV']:
1358         print "Warning: <fenv.h> not available; " \
1359               "forcing USE_FENV to False in", variant_dir + "."
1360         env['USE_FENV'] = False
1361
1362     if not env['USE_FENV']:
1363         print "Warning: No IEEE FP rounding mode control in", variant_dir + "."
1364         print "         FP results may deviate slightly from other platforms."
1365
1366     if env['EFENCE']:
1367         env.Append(LIBS=['efence'])
1368
1369     if env['USE_KVM']:
1370         if not have_kvm:
1371             print "Warning: Can not enable KVM, host seems to lack KVM support"
1372             env['USE_KVM'] = False
1373         elif not is_isa_kvm_compatible(env['TARGET_ISA']):
1374             print "Info: KVM support disabled due to unsupported host and " \
1375                 "target ISA combination"
1376             env['USE_KVM'] = False
1377
1378     # Warn about missing optional functionality
1379     if env['USE_KVM']:
1380         if not main['HAVE_PERF_ATTR_EXCLUDE_HOST']:
1381             print "Warning: perf_event headers lack support for the " \
1382                 "exclude_host attribute. KVM instruction counts will " \
1383                 "be inaccurate."
1384
1385     # Save sticky variable settings back to current variables file
1386     sticky_vars.Save(current_vars_file, env)
1387
1388     if env['USE_SSE2']:
1389         env.Append(CCFLAGS=['-msse2'])
1390
1391     # The src/SConscript file sets up the build rules in 'env' according
1392     # to the configured variables.  It returns a list of environments,
1393     # one for each variant build (debug, opt, etc.)
1394     SConscript('src/SConscript', variant_dir = variant_path, exports = 'env')
1395
1396 def pairwise(iterable):
1397     "s -> (s0,s1), (s1,s2), (s2, s3), ..."
1398     a, b = itertools.tee(iterable)
1399     b.next()
1400     return itertools.izip(a, b)
1401
1402 # Create false dependencies so SCons will parse ISAs, establish
1403 # dependencies, and setup the build Environments serially. Either
1404 # SCons (likely) and/or our SConscripts (possibly) cannot cope with -j
1405 # greater than 1. It appears to be standard race condition stuff; it
1406 # doesn't always fail, but usually, and the behaviors are different.
1407 # Every time I tried to remove this, builds would fail in some
1408 # creative new way. So, don't do that. You'll want to, though, because
1409 # tests/SConscript takes a long time to make its Environments.
1410 for t1, t2 in pairwise(sorted(all_isa_deps.iterkeys())):
1411     main.Depends('#%s-deps'     % t2, '#%s-deps'     % t1)
1412     main.Depends('#%s-environs' % t2, '#%s-environs' % t1)
1413
1414 # base help text
1415 Help('''
1416 Usage: scons [scons options] [build variables] [target(s)]
1417
1418 Extra scons options:
1419 %(options)s
1420
1421 Global build variables:
1422 %(global_vars)s
1423
1424 %(local_vars)s
1425 ''' % help_texts)