SConstruct revision 10866
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.
82try:
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)
89except SystemExit, e:
90    print """
91For 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
98try:
99    EnsurePythonVersion(2, 5)
100except SystemExit, e:
101    print """
102You can use a non-default installation of the Python interpreter by
103rearranging your PATH so that scons finds the non-default 'python' and
104'python-config' first.
105
106For more details, see:
107    http://gem5.org/wiki/index.php/Using_a_non-default_Python_installation
108"""
109    raise
110
111# Global Python includes
112import itertools
113import os
114import re
115import subprocess
116import sys
117
118from os import mkdir, environ
119from os.path import abspath, basename, dirname, expanduser, normpath
120from os.path import exists,  isdir, isfile
121from os.path import join as joinpath, split as splitpath
122
123# SCons includes
124import SCons
125import SCons.Node
126
127extra_python_paths = [
128    Dir('src/python').srcnode().abspath, # gem5 includes
129    Dir('ext/ply').srcnode().abspath, # ply is used by several files
130    ]
131
132sys.path[1:1] = extra_python_paths
133
134from m5.util import compareVersions, readCommand
135from m5.util.terminal import get_termcap
136
137help_texts = {
138    "options" : "",
139    "global_vars" : "",
140    "local_vars" : ""
141}
142
143Export("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.
157def 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
172AddLocalOption('--colors', dest='use_colors', action='store_true',
173               help="Add color to abbreviated scons output")
174AddLocalOption('--no-colors', dest='use_colors', action='store_false',
175               help="Don't add color to abbreviated scons output")
176AddLocalOption('--with-cxx-config', dest='with_cxx_config',
177               action='store_true',
178               help="Build with support for C++-based configuration")
179AddLocalOption('--default', dest='default', type='string', action='store',
180               help='Override which build_opts file to use for defaults')
181AddLocalOption('--ignore-style', dest='ignore_style', action='store_true',
182               help='Disable style checking hooks')
183AddLocalOption('--no-lto', dest='no_lto', action='store_true',
184               help='Disable Link-Time Optimization for fast')
185AddLocalOption('--update-ref', dest='update_ref', action='store_true',
186               help='Update test reference outputs')
187AddLocalOption('--verbose', dest='verbose', action='store_true',
188               help='Print full tool command lines')
189AddLocalOption('--without-python', dest='without_python',
190               action='store_true',
191               help='Build without Python configuration support')
192AddLocalOption('--without-tcmalloc', dest='without_tcmalloc',
193               action='store_true',
194               help='Disable linking against tcmalloc')
195AddLocalOption('--with-ubsan', dest='with_ubsan', action='store_true',
196               help='Build with Undefined Behavior Sanitizer if available')
197
198termcap = 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
207use_vars = set([ 'AS', 'AR', 'CC', 'CXX', 'HOME', 'LD_LIBRARY_PATH',
208                 'LIBRARY_PATH', 'PATH', 'PKG_CONFIG_PATH', 'PROTOC',
209                 'PYTHONPATH', 'RANLIB', 'SWIG', 'TERM' ])
210
211use_prefixes = [
212    "M5",           # M5 configuration (e.g., path to kernels)
213    "DISTCC_",      # distcc (distributed compiler wrapper) configuration
214    "CCACHE_",      # ccache (caching compiler wrapper) configuration
215    "CCC_",         # clang static analyzer configuration
216    ]
217
218use_env = {}
219for key,val in sorted(os.environ.iteritems()):
220    if key in use_vars or \
221            any([key.startswith(prefix) for prefix in use_prefixes]):
222        use_env[key] = val
223
224# Tell scons to avoid implicit command dependencies to avoid issues
225# with the param wrappes being compiled twice (see
226# http://scons.tigris.org/issues/show_bug.cgi?id=2811)
227main = Environment(ENV=use_env, IMPLICIT_COMMAND_DEPENDENCIES=0)
228main.Decider('MD5-timestamp')
229main.root = Dir(".")         # The current directory (where this file lives).
230main.srcdir = Dir("src")     # The source directory
231
232main_dict_keys = main.Dictionary().keys()
233
234# Check that we have a C/C++ compiler
235if not ('CC' in main_dict_keys and 'CXX' in main_dict_keys):
236    print "No C++ compiler installed (package g++ on Ubuntu and RedHat)"
237    Exit(1)
238
239# Check that swig is present
240if not 'SWIG' in main_dict_keys:
241    print "swig is not installed (package swig on Ubuntu and RedHat)"
242    Exit(1)
243
244# add useful python code PYTHONPATH so it can be used by subprocesses
245# as well
246main.AppendENVPath('PYTHONPATH', extra_python_paths)
247
248########################################################################
249#
250# Mercurial Stuff.
251#
252# If the gem5 directory is a mercurial repository, we should do some
253# extra things.
254#
255########################################################################
256
257hgdir = main.root.Dir(".hg")
258
259mercurial_style_message = """
260You're missing the gem5 style hook, which automatically checks your code
261against the gem5 style rules on hg commit and qrefresh commands.  This
262script will now install the hook in your .hg/hgrc file.
263Press enter to continue, or ctrl-c to abort: """
264
265mercurial_style_hook = """
266# The following lines were automatically added by gem5/SConstruct
267# to provide the gem5 style-checking hooks
268[extensions]
269style = %s/util/style.py
270
271[hooks]
272pretxncommit.style = python:style.check_style
273pre-qrefresh.style = python:style.check_style
274# End of SConstruct additions
275
276""" % (main.root.abspath)
277
278mercurial_lib_not_found = """
279Mercurial libraries cannot be found, ignoring style hook.  If
280you are a gem5 developer, please fix this and run the style
281hook. It is important.
282"""
283
284# Check for style hook and prompt for installation if it's not there.
285# Skip this if --ignore-style was specified, there's no .hg dir to
286# install a hook in, or there's no interactive terminal to prompt.
287if not GetOption('ignore_style') and hgdir.exists() and sys.stdin.isatty():
288    style_hook = True
289    try:
290        from mercurial import ui
291        ui = ui.ui()
292        ui.readconfig(hgdir.File('hgrc').abspath)
293        style_hook = ui.config('hooks', 'pretxncommit.style', None) and \
294                     ui.config('hooks', 'pre-qrefresh.style', None)
295    except ImportError:
296        print mercurial_lib_not_found
297
298    if not style_hook:
299        print mercurial_style_message,
300        # continue unless user does ctrl-c/ctrl-d etc.
301        try:
302            raw_input()
303        except:
304            print "Input exception, exiting scons.\n"
305            sys.exit(1)
306        hgrc_path = '%s/.hg/hgrc' % main.root.abspath
307        print "Adding style hook to", hgrc_path, "\n"
308        try:
309            hgrc = open(hgrc_path, 'a')
310            hgrc.write(mercurial_style_hook)
311            hgrc.close()
312        except:
313            print "Error updating", hgrc_path
314            sys.exit(1)
315
316
317###################################################
318#
319# Figure out which configurations to set up based on the path(s) of
320# the target(s).
321#
322###################################################
323
324# Find default configuration & binary.
325Default(environ.get('M5_DEFAULT_BINARY', 'build/ALPHA/gem5.debug'))
326
327# helper function: find last occurrence of element in list
328def rfind(l, elt, offs = -1):
329    for i in range(len(l)+offs, 0, -1):
330        if l[i] == elt:
331            return i
332    raise ValueError, "element not found"
333
334# Take a list of paths (or SCons Nodes) and return a list with all
335# paths made absolute and ~-expanded.  Paths will be interpreted
336# relative to the launch directory unless a different root is provided
337def makePathListAbsolute(path_list, root=GetLaunchDir()):
338    return [abspath(joinpath(root, expanduser(str(p))))
339            for p in path_list]
340
341# Each target must have 'build' in the interior of the path; the
342# directory below this will determine the build parameters.  For
343# example, for target 'foo/bar/build/ALPHA_SE/arch/alpha/blah.do' we
344# recognize that ALPHA_SE specifies the configuration because it
345# follow 'build' in the build path.
346
347# The funky assignment to "[:]" is needed to replace the list contents
348# in place rather than reassign the symbol to a new list, which
349# doesn't work (obviously!).
350BUILD_TARGETS[:] = makePathListAbsolute(BUILD_TARGETS)
351
352# Generate a list of the unique build roots and configs that the
353# collected targets reference.
354variant_paths = []
355build_root = None
356for t in BUILD_TARGETS:
357    path_dirs = t.split('/')
358    try:
359        build_top = rfind(path_dirs, 'build', -2)
360    except:
361        print "Error: no non-leaf 'build' dir found on target path", t
362        Exit(1)
363    this_build_root = joinpath('/',*path_dirs[:build_top+1])
364    if not build_root:
365        build_root = this_build_root
366    else:
367        if this_build_root != build_root:
368            print "Error: build targets not under same build root\n"\
369                  "  %s\n  %s" % (build_root, this_build_root)
370            Exit(1)
371    variant_path = joinpath('/',*path_dirs[:build_top+2])
372    if variant_path not in variant_paths:
373        variant_paths.append(variant_path)
374
375# Make sure build_root exists (might not if this is the first build there)
376if not isdir(build_root):
377    mkdir(build_root)
378main['BUILDROOT'] = build_root
379
380Export('main')
381
382main.SConsignFile(joinpath(build_root, "sconsign"))
383
384# Default duplicate option is to use hard links, but this messes up
385# when you use emacs to edit a file in the target dir, as emacs moves
386# file to file~ then copies to file, breaking the link.  Symbolic
387# (soft) links work better.
388main.SetOption('duplicate', 'soft-copy')
389
390#
391# Set up global sticky variables... these are common to an entire build
392# tree (not specific to a particular build like ALPHA_SE)
393#
394
395global_vars_file = joinpath(build_root, 'variables.global')
396
397global_vars = Variables(global_vars_file, args=ARGUMENTS)
398
399global_vars.AddVariables(
400    ('CC', 'C compiler', environ.get('CC', main['CC'])),
401    ('CXX', 'C++ compiler', environ.get('CXX', main['CXX'])),
402    ('SWIG', 'SWIG tool', environ.get('SWIG', main['SWIG'])),
403    ('PROTOC', 'protoc tool', environ.get('PROTOC', 'protoc')),
404    ('BATCH', 'Use batch pool for build and tests', False),
405    ('BATCH_CMD', 'Batch pool submission command name', 'qdo'),
406    ('M5_BUILD_CACHE', 'Cache built objects in this directory', False),
407    ('EXTRAS', 'Add extra directories to the compilation', '')
408    )
409
410# Update main environment with values from ARGUMENTS & global_vars_file
411global_vars.Update(main)
412help_texts["global_vars"] += global_vars.GenerateHelpText(main)
413
414# Save sticky variable settings back to current variables file
415global_vars.Save(global_vars_file, main)
416
417# Parse EXTRAS variable to build list of all directories where we're
418# look for sources etc.  This list is exported as extras_dir_list.
419base_dir = main.srcdir.abspath
420if main['EXTRAS']:
421    extras_dir_list = makePathListAbsolute(main['EXTRAS'].split(':'))
422else:
423    extras_dir_list = []
424
425Export('base_dir')
426Export('extras_dir_list')
427
428# the ext directory should be on the #includes path
429main.Append(CPPPATH=[Dir('ext')])
430
431def strip_build_path(path, env):
432    path = str(path)
433    variant_base = env['BUILDROOT'] + os.path.sep
434    if path.startswith(variant_base):
435        path = path[len(variant_base):]
436    elif path.startswith('build/'):
437        path = path[6:]
438    return path
439
440# Generate a string of the form:
441#   common/path/prefix/src1, src2 -> tgt1, tgt2
442# to print while building.
443class Transform(object):
444    # all specific color settings should be here and nowhere else
445    tool_color = termcap.Normal
446    pfx_color = termcap.Yellow
447    srcs_color = termcap.Yellow + termcap.Bold
448    arrow_color = termcap.Blue + termcap.Bold
449    tgts_color = termcap.Yellow + termcap.Bold
450
451    def __init__(self, tool, max_sources=99):
452        self.format = self.tool_color + (" [%8s] " % tool) \
453                      + self.pfx_color + "%s" \
454                      + self.srcs_color + "%s" \
455                      + self.arrow_color + " -> " \
456                      + self.tgts_color + "%s" \
457                      + termcap.Normal
458        self.max_sources = max_sources
459
460    def __call__(self, target, source, env, for_signature=None):
461        # truncate source list according to max_sources param
462        source = source[0:self.max_sources]
463        def strip(f):
464            return strip_build_path(str(f), env)
465        if len(source) > 0:
466            srcs = map(strip, source)
467        else:
468            srcs = ['']
469        tgts = map(strip, target)
470        # surprisingly, os.path.commonprefix is a dumb char-by-char string
471        # operation that has nothing to do with paths.
472        com_pfx = os.path.commonprefix(srcs + tgts)
473        com_pfx_len = len(com_pfx)
474        if com_pfx:
475            # do some cleanup and sanity checking on common prefix
476            if com_pfx[-1] == ".":
477                # prefix matches all but file extension: ok
478                # back up one to change 'foo.cc -> o' to 'foo.cc -> .o'
479                com_pfx = com_pfx[0:-1]
480            elif com_pfx[-1] == "/":
481                # common prefix is directory path: OK
482                pass
483            else:
484                src0_len = len(srcs[0])
485                tgt0_len = len(tgts[0])
486                if src0_len == com_pfx_len:
487                    # source is a substring of target, OK
488                    pass
489                elif tgt0_len == com_pfx_len:
490                    # target is a substring of source, need to back up to
491                    # avoid empty string on RHS of arrow
492                    sep_idx = com_pfx.rfind(".")
493                    if sep_idx != -1:
494                        com_pfx = com_pfx[0:sep_idx]
495                    else:
496                        com_pfx = ''
497                elif src0_len > com_pfx_len and srcs[0][com_pfx_len] == ".":
498                    # still splitting at file extension: ok
499                    pass
500                else:
501                    # probably a fluke; ignore it
502                    com_pfx = ''
503        # recalculate length in case com_pfx was modified
504        com_pfx_len = len(com_pfx)
505        def fmt(files):
506            f = map(lambda s: s[com_pfx_len:], files)
507            return ', '.join(f)
508        return self.format % (com_pfx, fmt(srcs), fmt(tgts))
509
510Export('Transform')
511
512# enable the regression script to use the termcap
513main['TERMCAP'] = termcap
514
515if GetOption('verbose'):
516    def MakeAction(action, string, *args, **kwargs):
517        return Action(action, *args, **kwargs)
518else:
519    MakeAction = Action
520    main['CCCOMSTR']        = Transform("CC")
521    main['CXXCOMSTR']       = Transform("CXX")
522    main['ASCOMSTR']        = Transform("AS")
523    main['SWIGCOMSTR']      = Transform("SWIG")
524    main['ARCOMSTR']        = Transform("AR", 0)
525    main['LINKCOMSTR']      = Transform("LINK", 0)
526    main['RANLIBCOMSTR']    = Transform("RANLIB", 0)
527    main['M4COMSTR']        = Transform("M4")
528    main['SHCCCOMSTR']      = Transform("SHCC")
529    main['SHCXXCOMSTR']     = Transform("SHCXX")
530Export('MakeAction')
531
532# Initialize the Link-Time Optimization (LTO) flags
533main['LTO_CCFLAGS'] = []
534main['LTO_LDFLAGS'] = []
535
536# According to the readme, tcmalloc works best if the compiler doesn't
537# assume that we're using the builtin malloc and friends. These flags
538# are compiler-specific, so we need to set them after we detect which
539# compiler we're using.
540main['TCMALLOC_CCFLAGS'] = []
541
542CXX_version = readCommand([main['CXX'],'--version'], exception=False)
543CXX_V = readCommand([main['CXX'],'-V'], exception=False)
544
545main['GCC'] = CXX_version and CXX_version.find('g++') >= 0
546main['CLANG'] = CXX_version and CXX_version.find('clang') >= 0
547if main['GCC'] + main['CLANG'] > 1:
548    print 'Error: How can we have two at the same time?'
549    Exit(1)
550
551# Set up default C++ compiler flags
552if main['GCC'] or main['CLANG']:
553    # As gcc and clang share many flags, do the common parts here
554    main.Append(CCFLAGS=['-pipe'])
555    main.Append(CCFLAGS=['-fno-strict-aliasing'])
556    # Enable -Wall and then disable the few warnings that we
557    # consistently violate
558    main.Append(CCFLAGS=['-Wall', '-Wno-sign-compare', '-Wundef'])
559    # We always compile using C++11, but only gcc >= 4.7 and clang 3.1
560    # actually use that name, so we stick with c++0x
561    main.Append(CXXFLAGS=['-std=c++0x'])
562    # Add selected sanity checks from -Wextra
563    main.Append(CXXFLAGS=['-Wmissing-field-initializers',
564                          '-Woverloaded-virtual'])
565else:
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
584if main['GCC']:
585    # Check for a supported version of gcc. >= 4.6 is chosen for its
586    # level of c++11 support. See
587    # http://gcc.gnu.org/projects/cxx0x.html for details. 4.6 is also
588    # the first version with proper LTO support.
589    gcc_version = readCommand([main['CXX'], '-dumpversion'], exception=False)
590    if compareVersions(gcc_version, "4.6") < 0:
591        print 'Error: gcc version 4.6 or newer required.'
592        print '       Installed version:', gcc_version
593        Exit(1)
594
595    main['GCC_VERSION'] = gcc_version
596
597    # gcc from version 4.8 and above generates "rep; ret" instructions
598    # to avoid performance penalties on certain AMD chips. Older
599    # assemblers detect this as an error, "Error: expecting string
600    # instruction after `rep'"
601    if compareVersions(gcc_version, "4.8") > 0:
602        as_version_raw = readCommand([main['AS'], '-v', '/dev/null'],
603                                     exception=False).split()
604
605        # version strings may contain extra distro-specific
606        # qualifiers, so play it safe and keep only what comes before
607        # the first hyphen
608        as_version = as_version_raw[-1].split('-')[0] if as_version_raw \
609            else None
610
611        if not as_version or compareVersions(as_version, "2.23") < 0:
612            print termcap.Yellow + termcap.Bold + \
613                'Warning: This combination of gcc and binutils have' + \
614                ' known incompatibilities.\n' + \
615                '         If you encounter build problems, please update ' + \
616                'binutils to 2.23.' + \
617                termcap.Normal
618
619    # Make sure we warn if the user has requested to compile with the
620    # Undefined Benahvior Sanitizer and this version of gcc does not
621    # support it.
622    if GetOption('with_ubsan') and \
623            compareVersions(gcc_version, '4.9') < 0:
624        print termcap.Yellow + termcap.Bold + \
625            'Warning: UBSan is only supported using gcc 4.9 and later.' + \
626            termcap.Normal
627
628    # Add the appropriate Link-Time Optimization (LTO) flags
629    # unless LTO is explicitly turned off. Note that these flags
630    # are only used by the fast target.
631    if not GetOption('no_lto'):
632        # Pass the LTO flag when compiling to produce GIMPLE
633        # output, we merely create the flags here and only append
634        # them later
635        main['LTO_CCFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
636
637        # Use the same amount of jobs for LTO as we are running
638        # scons with
639        main['LTO_LDFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
640
641    main.Append(TCMALLOC_CCFLAGS=['-fno-builtin-malloc', '-fno-builtin-calloc',
642                                  '-fno-builtin-realloc', '-fno-builtin-free'])
643
644elif main['CLANG']:
645    # Check for a supported version of clang, >= 3.0 is needed to
646    # support similar features as gcc 4.6. See
647    # http://clang.llvm.org/cxx_status.html for details
648    clang_version_re = re.compile(".* version (\d+\.\d+)")
649    clang_version_match = clang_version_re.search(CXX_version)
650    if (clang_version_match):
651        clang_version = clang_version_match.groups()[0]
652        if compareVersions(clang_version, "3.0") < 0:
653            print 'Error: clang version 3.0 or newer required.'
654            print '       Installed version:', clang_version
655            Exit(1)
656    else:
657        print 'Error: Unable to determine clang version.'
658        Exit(1)
659
660    # clang has a few additional warnings that we disable,
661    # tautological comparisons are allowed due to unsigned integers
662    # being compared to constants that happen to be 0, and extraneous
663    # parantheses are allowed due to Ruby's printing of the AST,
664    # finally self assignments are allowed as the generated CPU code
665    # is relying on this
666    main.Append(CCFLAGS=['-Wno-tautological-compare',
667                         '-Wno-parentheses',
668                         '-Wno-self-assign',
669                         # Some versions of libstdc++ (4.8?) seem to
670                         # use struct hash and class hash
671                         # interchangeably.
672                         '-Wno-mismatched-tags',
673                         ])
674
675    main.Append(TCMALLOC_CCFLAGS=['-fno-builtin'])
676
677    # On Mac OS X/Darwin we need to also use libc++ (part of XCode) as
678    # opposed to libstdc++, as the later is dated.
679    if sys.platform == "darwin":
680        main.Append(CXXFLAGS=['-stdlib=libc++'])
681        main.Append(LIBS=['c++'])
682
683else:
684    print termcap.Yellow + termcap.Bold + 'Error' + termcap.Normal,
685    print "Don't know what compiler options to use for your compiler."
686    print termcap.Yellow + '       compiler:' + termcap.Normal, main['CXX']
687    print termcap.Yellow + '       version:' + termcap.Normal,
688    if not CXX_version:
689        print termcap.Yellow + termcap.Bold + "COMMAND NOT FOUND!" +\
690               termcap.Normal
691    else:
692        print CXX_version.replace('\n', '<nl>')
693    print "       If you're trying to use a compiler other than GCC"
694    print "       or clang, there appears to be something wrong with your"
695    print "       environment."
696    print "       "
697    print "       If you are trying to use a compiler other than those listed"
698    print "       above you will need to ease fix SConstruct and "
699    print "       src/SConscript to support that compiler."
700    Exit(1)
701
702# Set up common yacc/bison flags (needed for Ruby)
703main['YACCFLAGS'] = '-d'
704main['YACCHXXFILESUFFIX'] = '.hh'
705
706# Do this after we save setting back, or else we'll tack on an
707# extra 'qdo' every time we run scons.
708if main['BATCH']:
709    main['CC']     = main['BATCH_CMD'] + ' ' + main['CC']
710    main['CXX']    = main['BATCH_CMD'] + ' ' + main['CXX']
711    main['AS']     = main['BATCH_CMD'] + ' ' + main['AS']
712    main['AR']     = main['BATCH_CMD'] + ' ' + main['AR']
713    main['RANLIB'] = main['BATCH_CMD'] + ' ' + main['RANLIB']
714
715if sys.platform == 'cygwin':
716    # cygwin has some header file issues...
717    main.Append(CCFLAGS=["-Wno-uninitialized"])
718
719# Check for the protobuf compiler
720protoc_version = readCommand([main['PROTOC'], '--version'],
721                             exception='').split()
722
723# First two words should be "libprotoc x.y.z"
724if len(protoc_version) < 2 or protoc_version[0] != 'libprotoc':
725    print termcap.Yellow + termcap.Bold + \
726        'Warning: Protocol buffer compiler (protoc) not found.\n' + \
727        '         Please install protobuf-compiler for tracing support.' + \
728        termcap.Normal
729    main['PROTOC'] = False
730else:
731    # Based on the availability of the compress stream wrappers,
732    # require 2.1.0
733    min_protoc_version = '2.1.0'
734    if compareVersions(protoc_version[1], min_protoc_version) < 0:
735        print termcap.Yellow + termcap.Bold + \
736            'Warning: protoc version', min_protoc_version, \
737            'or newer required.\n' + \
738            '         Installed version:', protoc_version[1], \
739            termcap.Normal
740        main['PROTOC'] = False
741    else:
742        # Attempt to determine the appropriate include path and
743        # library path using pkg-config, that means we also need to
744        # check for pkg-config. Note that it is possible to use
745        # protobuf without the involvement of pkg-config. Later on we
746        # check go a library config check and at that point the test
747        # will fail if libprotobuf cannot be found.
748        if readCommand(['pkg-config', '--version'], exception=''):
749            try:
750                # Attempt to establish what linking flags to add for protobuf
751                # using pkg-config
752                main.ParseConfig('pkg-config --cflags --libs-only-L protobuf')
753            except:
754                print termcap.Yellow + termcap.Bold + \
755                    'Warning: pkg-config could not get protobuf flags.' + \
756                    termcap.Normal
757
758# Check for SWIG
759if not main.has_key('SWIG'):
760    print 'Error: SWIG utility not found.'
761    print '       Please install (see http://www.swig.org) and retry.'
762    Exit(1)
763
764# Check for appropriate SWIG version
765swig_version = readCommand([main['SWIG'], '-version'], exception='').split()
766# First 3 words should be "SWIG Version x.y.z"
767if len(swig_version) < 3 or \
768        swig_version[0] != 'SWIG' or swig_version[1] != 'Version':
769    print 'Error determining SWIG version.'
770    Exit(1)
771
772min_swig_version = '2.0.4'
773if compareVersions(swig_version[2], min_swig_version) < 0:
774    print 'Error: SWIG version', min_swig_version, 'or newer required.'
775    print '       Installed version:', swig_version[2]
776    Exit(1)
777
778# Check for known incompatibilities. The standard library shipped with
779# gcc >= 4.9 does not play well with swig versions prior to 3.0
780if main['GCC'] and compareVersions(gcc_version, '4.9') >= 0 and \
781        compareVersions(swig_version[2], '3.0') < 0:
782    print termcap.Yellow + termcap.Bold + \
783        'Warning: This combination of gcc and swig have' + \
784        ' known incompatibilities.\n' + \
785        '         If you encounter build problems, please update ' + \
786        'swig to 3.0 or later.' + \
787        termcap.Normal
788
789# Set up SWIG flags & scanner
790swig_flags=Split('-c++ -python -modern -templatereduce $_CPPINCFLAGS')
791main.Append(SWIGFLAGS=swig_flags)
792
793# Check for 'timeout' from GNU coreutils. If present, regressions will
794# be run with a time limit. We require version 8.13 since we rely on
795# support for the '--foreground' option.
796timeout_lines = readCommand(['timeout', '--version'],
797                            exception='').splitlines()
798# Get the first line and tokenize it
799timeout_version = timeout_lines[0].split() if timeout_lines else []
800main['TIMEOUT'] =  timeout_version and \
801    compareVersions(timeout_version[-1], '8.13') >= 0
802
803# filter out all existing swig scanners, they mess up the dependency
804# stuff for some reason
805scanners = []
806for scanner in main['SCANNERS']:
807    skeys = scanner.skeys
808    if skeys == '.i':
809        continue
810
811    if isinstance(skeys, (list, tuple)) and '.i' in skeys:
812        continue
813
814    scanners.append(scanner)
815
816# add the new swig scanner that we like better
817from SCons.Scanner import ClassicCPP as CPPScanner
818swig_inc_re = '^[ \t]*[%,#][ \t]*(?:include|import)[ \t]*(<|")([^>"]+)(>|")'
819scanners.append(CPPScanner("SwigScan", [ ".i" ], "CPPPATH", swig_inc_re))
820
821# replace the scanners list that has what we want
822main['SCANNERS'] = scanners
823
824# Add a custom Check function to the Configure context so that we can
825# figure out if the compiler adds leading underscores to global
826# variables.  This is needed for the autogenerated asm files that we
827# use for embedding the python code.
828def CheckLeading(context):
829    context.Message("Checking for leading underscore in global variables...")
830    # 1) Define a global variable called x from asm so the C compiler
831    #    won't change the symbol at all.
832    # 2) Declare that variable.
833    # 3) Use the variable
834    #
835    # If the compiler prepends an underscore, this will successfully
836    # link because the external symbol 'x' will be called '_x' which
837    # was defined by the asm statement.  If the compiler does not
838    # prepend an underscore, this will not successfully link because
839    # '_x' will have been defined by assembly, while the C portion of
840    # the code will be trying to use 'x'
841    ret = context.TryLink('''
842        asm(".globl _x; _x: .byte 0");
843        extern int x;
844        int main() { return x; }
845        ''', extension=".c")
846    context.env.Append(LEADING_UNDERSCORE=ret)
847    context.Result(ret)
848    return ret
849
850# Add a custom Check function to test for structure members.
851def CheckMember(context, include, decl, member, include_quotes="<>"):
852    context.Message("Checking for member %s in %s..." %
853                    (member, decl))
854    text = """
855#include %(header)s
856int main(){
857  %(decl)s test;
858  (void)test.%(member)s;
859  return 0;
860};
861""" % { "header" : include_quotes[0] + include + include_quotes[1],
862        "decl" : decl,
863        "member" : member,
864        }
865
866    ret = context.TryCompile(text, extension=".cc")
867    context.Result(ret)
868    return ret
869
870# Platform-specific configuration.  Note again that we assume that all
871# builds under a given build root run on the same host platform.
872conf = Configure(main,
873                 conf_dir = joinpath(build_root, '.scons_config'),
874                 log_file = joinpath(build_root, 'scons_config.log'),
875                 custom_tests = {
876        'CheckLeading' : CheckLeading,
877        'CheckMember' : CheckMember,
878        })
879
880# Check for leading underscores.  Don't really need to worry either
881# way so don't need to check the return code.
882conf.CheckLeading()
883
884# Check if we should compile a 64 bit binary on Mac OS X/Darwin
885try:
886    import platform
887    uname = platform.uname()
888    if uname[0] == 'Darwin' and compareVersions(uname[2], '9.0.0') >= 0:
889        if int(readCommand('sysctl -n hw.cpu64bit_capable')[0]):
890            main.Append(CCFLAGS=['-arch', 'x86_64'])
891            main.Append(CFLAGS=['-arch', 'x86_64'])
892            main.Append(LINKFLAGS=['-arch', 'x86_64'])
893            main.Append(ASFLAGS=['-arch', 'x86_64'])
894except:
895    pass
896
897# Recent versions of scons substitute a "Null" object for Configure()
898# when configuration isn't necessary, e.g., if the "--help" option is
899# present.  Unfortuantely this Null object always returns false,
900# breaking all our configuration checks.  We replace it with our own
901# more optimistic null object that returns True instead.
902if not conf:
903    def NullCheck(*args, **kwargs):
904        return True
905
906    class NullConf:
907        def __init__(self, env):
908            self.env = env
909        def Finish(self):
910            return self.env
911        def __getattr__(self, mname):
912            return NullCheck
913
914    conf = NullConf(main)
915
916# Cache build files in the supplied directory.
917if main['M5_BUILD_CACHE']:
918    print 'Using build cache located at', main['M5_BUILD_CACHE']
919    CacheDir(main['M5_BUILD_CACHE'])
920
921if not GetOption('without_python'):
922    # Find Python include and library directories for embedding the
923    # interpreter. We rely on python-config to resolve the appropriate
924    # includes and linker flags. ParseConfig does not seem to understand
925    # the more exotic linker flags such as -Xlinker and -export-dynamic so
926    # we add them explicitly below. If you want to link in an alternate
927    # version of python, see above for instructions on how to invoke
928    # scons with the appropriate PATH set.
929    #
930    # First we check if python2-config exists, else we use python-config
931    python_config = readCommand(['which', 'python2-config'],
932                                exception='').strip()
933    if not os.path.exists(python_config):
934        python_config = readCommand(['which', 'python-config'],
935                                    exception='').strip()
936    py_includes = readCommand([python_config, '--includes'],
937                              exception='').split()
938    # Strip the -I from the include folders before adding them to the
939    # CPPPATH
940    main.Append(CPPPATH=map(lambda inc: inc[2:], py_includes))
941
942    # Read the linker flags and split them into libraries and other link
943    # flags. The libraries are added later through the call the CheckLib.
944    py_ld_flags = readCommand([python_config, '--ldflags'],
945        exception='').split()
946    py_libs = []
947    for lib in py_ld_flags:
948         if not lib.startswith('-l'):
949             main.Append(LINKFLAGS=[lib])
950         else:
951             lib = lib[2:]
952             if lib not in py_libs:
953                 py_libs.append(lib)
954
955    # verify that this stuff works
956    if not conf.CheckHeader('Python.h', '<>'):
957        print "Error: can't find Python.h header in", py_includes
958        print "Install Python headers (package python-dev on Ubuntu and RedHat)"
959        Exit(1)
960
961    for lib in py_libs:
962        if not conf.CheckLib(lib):
963            print "Error: can't find library %s required by python" % lib
964            Exit(1)
965
966# On Solaris you need to use libsocket for socket ops
967if not conf.CheckLibWithHeader(None, 'sys/socket.h', 'C++', 'accept(0,0,0);'):
968   if not conf.CheckLibWithHeader('socket', 'sys/socket.h', 'C++', 'accept(0,0,0);'):
969       print "Can't find library with socket calls (e.g. accept())"
970       Exit(1)
971
972# Check for zlib.  If the check passes, libz will be automatically
973# added to the LIBS environment variable.
974if not conf.CheckLibWithHeader('z', 'zlib.h', 'C++','zlibVersion();'):
975    print 'Error: did not find needed zlib compression library '\
976          'and/or zlib.h header file.'
977    print '       Please install zlib and try again.'
978    Exit(1)
979
980# If we have the protobuf compiler, also make sure we have the
981# development libraries. If the check passes, libprotobuf will be
982# automatically added to the LIBS environment variable. After
983# this, we can use the HAVE_PROTOBUF flag to determine if we have
984# got both protoc and libprotobuf available.
985main['HAVE_PROTOBUF'] = main['PROTOC'] and \
986    conf.CheckLibWithHeader('protobuf', 'google/protobuf/message.h',
987                            'C++', 'GOOGLE_PROTOBUF_VERIFY_VERSION;')
988
989# If we have the compiler but not the library, print another warning.
990if main['PROTOC'] and not main['HAVE_PROTOBUF']:
991    print termcap.Yellow + termcap.Bold + \
992        'Warning: did not find protocol buffer library and/or headers.\n' + \
993    '       Please install libprotobuf-dev for tracing support.' + \
994    termcap.Normal
995
996# Check for librt.
997have_posix_clock = \
998    conf.CheckLibWithHeader(None, 'time.h', 'C',
999                            'clock_nanosleep(0,0,NULL,NULL);') or \
1000    conf.CheckLibWithHeader('rt', 'time.h', 'C',
1001                            'clock_nanosleep(0,0,NULL,NULL);')
1002
1003have_posix_timers = \
1004    conf.CheckLibWithHeader([None, 'rt'], [ 'time.h', 'signal.h' ], 'C',
1005                            'timer_create(CLOCK_MONOTONIC, NULL, NULL);')
1006
1007if not GetOption('without_tcmalloc'):
1008    if conf.CheckLib('tcmalloc'):
1009        main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
1010    elif conf.CheckLib('tcmalloc_minimal'):
1011        main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
1012    else:
1013        print termcap.Yellow + termcap.Bold + \
1014              "You can get a 12% performance improvement by "\
1015              "installing tcmalloc (libgoogle-perftools-dev package "\
1016              "on Ubuntu or RedHat)." + termcap.Normal
1017
1018if not have_posix_clock:
1019    print "Can't find library for POSIX clocks."
1020
1021# Check for <fenv.h> (C99 FP environment control)
1022have_fenv = conf.CheckHeader('fenv.h', '<>')
1023if not have_fenv:
1024    print "Warning: Header file <fenv.h> not found."
1025    print "         This host has no IEEE FP rounding mode control."
1026
1027# Check if we should enable KVM-based hardware virtualization. The API
1028# we rely on exists since version 2.6.36 of the kernel, but somehow
1029# the KVM_API_VERSION does not reflect the change. We test for one of
1030# the types as a fall back.
1031have_kvm = conf.CheckHeader('linux/kvm.h', '<>')
1032if not have_kvm:
1033    print "Info: Compatible header file <linux/kvm.h> not found, " \
1034        "disabling KVM support."
1035
1036# x86 needs support for xsave. We test for the structure here since we
1037# won't be able to run new tests by the time we know which ISA we're
1038# targeting.
1039have_kvm_xsave = conf.CheckTypeSize('struct kvm_xsave',
1040                                    '#include <linux/kvm.h>') != 0
1041
1042# Check if the requested target ISA is compatible with the host
1043def is_isa_kvm_compatible(isa):
1044    try:
1045        import platform
1046        host_isa = platform.machine()
1047    except:
1048        print "Warning: Failed to determine host ISA."
1049        return False
1050
1051    if not have_posix_timers:
1052        print "Warning: Can not enable KVM, host seems to lack support " \
1053            "for POSIX timers"
1054        return False
1055
1056    if isa == "arm":
1057        return host_isa in ( "armv7l", "aarch64" )
1058    elif isa == "x86":
1059        if host_isa != "x86_64":
1060            return False
1061
1062        if not have_kvm_xsave:
1063            print "KVM on x86 requires xsave support in kernel headers."
1064            return False
1065
1066        return True
1067    else:
1068        return False
1069
1070
1071# Check if the exclude_host attribute is available. We want this to
1072# get accurate instruction counts in KVM.
1073main['HAVE_PERF_ATTR_EXCLUDE_HOST'] = conf.CheckMember(
1074    'linux/perf_event.h', 'struct perf_event_attr', 'exclude_host')
1075
1076
1077######################################################################
1078#
1079# Finish the configuration
1080#
1081main = conf.Finish()
1082
1083######################################################################
1084#
1085# Collect all non-global variables
1086#
1087
1088# Define the universe of supported ISAs
1089all_isa_list = [ ]
1090Export('all_isa_list')
1091
1092class CpuModel(object):
1093    '''The CpuModel class encapsulates everything the ISA parser needs to
1094    know about a particular CPU model.'''
1095
1096    # Dict of available CPU model objects.  Accessible as CpuModel.dict.
1097    dict = {}
1098
1099    # Constructor.  Automatically adds models to CpuModel.dict.
1100    def __init__(self, name, default=False):
1101        self.name = name           # name of model
1102
1103        # This cpu is enabled by default
1104        self.default = default
1105
1106        # Add self to dict
1107        if name in CpuModel.dict:
1108            raise AttributeError, "CpuModel '%s' already registered" % name
1109        CpuModel.dict[name] = self
1110
1111Export('CpuModel')
1112
1113# Sticky variables get saved in the variables file so they persist from
1114# one invocation to the next (unless overridden, in which case the new
1115# value becomes sticky).
1116sticky_vars = Variables(args=ARGUMENTS)
1117Export('sticky_vars')
1118
1119# Sticky variables that should be exported
1120export_vars = []
1121Export('export_vars')
1122
1123# For Ruby
1124all_protocols = []
1125Export('all_protocols')
1126protocol_dirs = []
1127Export('protocol_dirs')
1128slicc_includes = []
1129Export('slicc_includes')
1130
1131# Walk the tree and execute all SConsopts scripts that wil add to the
1132# above variables
1133if GetOption('verbose'):
1134    print "Reading SConsopts"
1135for bdir in [ base_dir ] + extras_dir_list:
1136    if not isdir(bdir):
1137        print "Error: directory '%s' does not exist" % bdir
1138        Exit(1)
1139    for root, dirs, files in os.walk(bdir):
1140        if 'SConsopts' in files:
1141            if GetOption('verbose'):
1142                print "Reading", joinpath(root, 'SConsopts')
1143            SConscript(joinpath(root, 'SConsopts'))
1144
1145all_isa_list.sort()
1146
1147sticky_vars.AddVariables(
1148    EnumVariable('TARGET_ISA', 'Target ISA', 'alpha', all_isa_list),
1149    ListVariable('CPU_MODELS', 'CPU models',
1150                 sorted(n for n,m in CpuModel.dict.iteritems() if m.default),
1151                 sorted(CpuModel.dict.keys())),
1152    BoolVariable('EFENCE', 'Link with Electric Fence malloc debugger',
1153                 False),
1154    BoolVariable('SS_COMPATIBLE_FP',
1155                 'Make floating-point results compatible with SimpleScalar',
1156                 False),
1157    BoolVariable('USE_SSE2',
1158                 'Compile for SSE2 (-msse2) to get IEEE FP on x86 hosts',
1159                 False),
1160    BoolVariable('USE_POSIX_CLOCK', 'Use POSIX Clocks', have_posix_clock),
1161    BoolVariable('USE_FENV', 'Use <fenv.h> IEEE mode control', have_fenv),
1162    BoolVariable('CP_ANNOTATE', 'Enable critical path annotation capability', False),
1163    BoolVariable('USE_KVM', 'Enable hardware virtualized (KVM) CPU models', have_kvm),
1164    EnumVariable('PROTOCOL', 'Coherence protocol for Ruby', 'None',
1165                  all_protocols),
1166    )
1167
1168# These variables get exported to #defines in config/*.hh (see src/SConscript).
1169export_vars += ['USE_FENV', 'SS_COMPATIBLE_FP', 'TARGET_ISA', 'CP_ANNOTATE',
1170                'USE_POSIX_CLOCK', 'USE_KVM', 'PROTOCOL', 'HAVE_PROTOBUF',
1171                'HAVE_PERF_ATTR_EXCLUDE_HOST']
1172
1173###################################################
1174#
1175# Define a SCons builder for configuration flag headers.
1176#
1177###################################################
1178
1179# This function generates a config header file that #defines the
1180# variable symbol to the current variable setting (0 or 1).  The source
1181# operands are the name of the variable and a Value node containing the
1182# value of the variable.
1183def build_config_file(target, source, env):
1184    (variable, value) = [s.get_contents() for s in source]
1185    f = file(str(target[0]), 'w')
1186    print >> f, '#define', variable, value
1187    f.close()
1188    return None
1189
1190# Combine the two functions into a scons Action object.
1191config_action = MakeAction(build_config_file, Transform("CONFIG H", 2))
1192
1193# The emitter munges the source & target node lists to reflect what
1194# we're really doing.
1195def config_emitter(target, source, env):
1196    # extract variable name from Builder arg
1197    variable = str(target[0])
1198    # True target is config header file
1199    target = joinpath('config', variable.lower() + '.hh')
1200    val = env[variable]
1201    if isinstance(val, bool):
1202        # Force value to 0/1
1203        val = int(val)
1204    elif isinstance(val, str):
1205        val = '"' + val + '"'
1206
1207    # Sources are variable name & value (packaged in SCons Value nodes)
1208    return ([target], [Value(variable), Value(val)])
1209
1210config_builder = Builder(emitter = config_emitter, action = config_action)
1211
1212main.Append(BUILDERS = { 'ConfigFile' : config_builder })
1213
1214# libelf build is shared across all configs in the build root.
1215main.SConscript('ext/libelf/SConscript',
1216                variant_dir = joinpath(build_root, 'libelf'))
1217
1218# gzstream build is shared across all configs in the build root.
1219main.SConscript('ext/gzstream/SConscript',
1220                variant_dir = joinpath(build_root, 'gzstream'))
1221
1222# libfdt build is shared across all configs in the build root.
1223main.SConscript('ext/libfdt/SConscript',
1224                variant_dir = joinpath(build_root, 'libfdt'))
1225
1226# fputils build is shared across all configs in the build root.
1227main.SConscript('ext/fputils/SConscript',
1228                variant_dir = joinpath(build_root, 'fputils'))
1229
1230# DRAMSim2 build is shared across all configs in the build root.
1231main.SConscript('ext/dramsim2/SConscript',
1232                variant_dir = joinpath(build_root, 'dramsim2'))
1233
1234# DRAMPower build is shared across all configs in the build root.
1235main.SConscript('ext/drampower/SConscript',
1236                variant_dir = joinpath(build_root, 'drampower'))
1237
1238###################################################
1239#
1240# This function is used to set up a directory with switching headers
1241#
1242###################################################
1243
1244main['ALL_ISA_LIST'] = all_isa_list
1245all_isa_deps = {}
1246def make_switching_dir(dname, switch_headers, env):
1247    # Generate the header.  target[0] is the full path of the output
1248    # header to generate.  'source' is a dummy variable, since we get the
1249    # list of ISAs from env['ALL_ISA_LIST'].
1250    def gen_switch_hdr(target, source, env):
1251        fname = str(target[0])
1252        isa = env['TARGET_ISA'].lower()
1253        try:
1254            f = open(fname, 'w')
1255            print >>f, '#include "%s/%s/%s"' % (dname, isa, basename(fname))
1256            f.close()
1257        except IOError:
1258            print "Failed to create %s" % fname
1259            raise
1260
1261    # Build SCons Action object. 'varlist' specifies env vars that this
1262    # action depends on; when env['ALL_ISA_LIST'] changes these actions
1263    # should get re-executed.
1264    switch_hdr_action = MakeAction(gen_switch_hdr,
1265                          Transform("GENERATE"), varlist=['ALL_ISA_LIST'])
1266
1267    # Instantiate actions for each header
1268    for hdr in switch_headers:
1269        env.Command(hdr, [], switch_hdr_action)
1270
1271    isa_target = Dir('.').up().name.lower().replace('_', '-')
1272    env['PHONY_BASE'] = '#'+isa_target
1273    all_isa_deps[isa_target] = None
1274
1275Export('make_switching_dir')
1276
1277# all-isas -> all-deps -> all-environs -> all_targets
1278main.Alias('#all-isas', [])
1279main.Alias('#all-deps', '#all-isas')
1280
1281# Dummy target to ensure all environments are created before telling
1282# SCons what to actually make (the command line arguments).  We attach
1283# them to the dependence graph after the environments are complete.
1284ORIG_BUILD_TARGETS = list(BUILD_TARGETS) # force a copy; gets closure to work.
1285def environsComplete(target, source, env):
1286    for t in ORIG_BUILD_TARGETS:
1287        main.Depends('#all-targets', t)
1288
1289# Each build/* switching_dir attaches its *-environs target to #all-environs.
1290main.Append(BUILDERS = {'CompleteEnvirons' :
1291                        Builder(action=MakeAction(environsComplete, None))})
1292main.CompleteEnvirons('#all-environs', [])
1293
1294def doNothing(**ignored): pass
1295main.Append(BUILDERS = {'Dummy': Builder(action=MakeAction(doNothing, None))})
1296
1297# The final target to which all the original targets ultimately get attached.
1298main.Dummy('#all-targets', '#all-environs')
1299BUILD_TARGETS[:] = ['#all-targets']
1300
1301###################################################
1302#
1303# Define build environments for selected configurations.
1304#
1305###################################################
1306
1307for variant_path in variant_paths:
1308    if not GetOption('silent'):
1309        print "Building in", variant_path
1310
1311    # Make a copy of the build-root environment to use for this config.
1312    env = main.Clone()
1313    env['BUILDDIR'] = variant_path
1314
1315    # variant_dir is the tail component of build path, and is used to
1316    # determine the build parameters (e.g., 'ALPHA_SE')
1317    (build_root, variant_dir) = splitpath(variant_path)
1318
1319    # Set env variables according to the build directory config.
1320    sticky_vars.files = []
1321    # Variables for $BUILD_ROOT/$VARIANT_DIR are stored in
1322    # $BUILD_ROOT/variables/$VARIANT_DIR so you can nuke
1323    # $BUILD_ROOT/$VARIANT_DIR without losing your variables settings.
1324    current_vars_file = joinpath(build_root, 'variables', variant_dir)
1325    if isfile(current_vars_file):
1326        sticky_vars.files.append(current_vars_file)
1327        if not GetOption('silent'):
1328            print "Using saved variables file %s" % current_vars_file
1329    else:
1330        # Build dir-specific variables file doesn't exist.
1331
1332        # Make sure the directory is there so we can create it later
1333        opt_dir = dirname(current_vars_file)
1334        if not isdir(opt_dir):
1335            mkdir(opt_dir)
1336
1337        # Get default build variables from source tree.  Variables are
1338        # normally determined by name of $VARIANT_DIR, but can be
1339        # overridden by '--default=' arg on command line.
1340        default = GetOption('default')
1341        opts_dir = joinpath(main.root.abspath, 'build_opts')
1342        if default:
1343            default_vars_files = [joinpath(build_root, 'variables', default),
1344                                  joinpath(opts_dir, default)]
1345        else:
1346            default_vars_files = [joinpath(opts_dir, variant_dir)]
1347        existing_files = filter(isfile, default_vars_files)
1348        if existing_files:
1349            default_vars_file = existing_files[0]
1350            sticky_vars.files.append(default_vars_file)
1351            print "Variables file %s not found,\n  using defaults in %s" \
1352                  % (current_vars_file, default_vars_file)
1353        else:
1354            print "Error: cannot find variables file %s or " \
1355                  "default file(s) %s" \
1356                  % (current_vars_file, ' or '.join(default_vars_files))
1357            Exit(1)
1358
1359    # Apply current variable settings to env
1360    sticky_vars.Update(env)
1361
1362    help_texts["local_vars"] += \
1363        "Build variables for %s:\n" % variant_dir \
1364                 + sticky_vars.GenerateHelpText(env)
1365
1366    # Process variable settings.
1367
1368    if not have_fenv and env['USE_FENV']:
1369        print "Warning: <fenv.h> not available; " \
1370              "forcing USE_FENV to False in", variant_dir + "."
1371        env['USE_FENV'] = False
1372
1373    if not env['USE_FENV']:
1374        print "Warning: No IEEE FP rounding mode control in", variant_dir + "."
1375        print "         FP results may deviate slightly from other platforms."
1376
1377    if env['EFENCE']:
1378        env.Append(LIBS=['efence'])
1379
1380    if env['USE_KVM']:
1381        if not have_kvm:
1382            print "Warning: Can not enable KVM, host seems to lack KVM support"
1383            env['USE_KVM'] = False
1384        elif not is_isa_kvm_compatible(env['TARGET_ISA']):
1385            print "Info: KVM support disabled due to unsupported host and " \
1386                "target ISA combination"
1387            env['USE_KVM'] = False
1388
1389    # Warn about missing optional functionality
1390    if env['USE_KVM']:
1391        if not main['HAVE_PERF_ATTR_EXCLUDE_HOST']:
1392            print "Warning: perf_event headers lack support for the " \
1393                "exclude_host attribute. KVM instruction counts will " \
1394                "be inaccurate."
1395
1396    # Save sticky variable settings back to current variables file
1397    sticky_vars.Save(current_vars_file, env)
1398
1399    if env['USE_SSE2']:
1400        env.Append(CCFLAGS=['-msse2'])
1401
1402    # The src/SConscript file sets up the build rules in 'env' according
1403    # to the configured variables.  It returns a list of environments,
1404    # one for each variant build (debug, opt, etc.)
1405    SConscript('src/SConscript', variant_dir = variant_path, exports = 'env')
1406
1407def pairwise(iterable):
1408    "s -> (s0,s1), (s1,s2), (s2, s3), ..."
1409    a, b = itertools.tee(iterable)
1410    b.next()
1411    return itertools.izip(a, b)
1412
1413# Create false dependencies so SCons will parse ISAs, establish
1414# dependencies, and setup the build Environments serially. Either
1415# SCons (likely) and/or our SConscripts (possibly) cannot cope with -j
1416# greater than 1. It appears to be standard race condition stuff; it
1417# doesn't always fail, but usually, and the behaviors are different.
1418# Every time I tried to remove this, builds would fail in some
1419# creative new way. So, don't do that. You'll want to, though, because
1420# tests/SConscript takes a long time to make its Environments.
1421for t1, t2 in pairwise(sorted(all_isa_deps.iterkeys())):
1422    main.Depends('#%s-deps'     % t2, '#%s-deps'     % t1)
1423    main.Depends('#%s-environs' % t2, '#%s-environs' % t1)
1424
1425# base help text
1426Help('''
1427Usage: scons [scons options] [build variables] [target(s)]
1428
1429Extra scons options:
1430%(options)s
1431
1432Global build variables:
1433%(global_vars)s
1434
1435%(local_vars)s
1436''' % help_texts)
1437