SConstruct revision 10841
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 = readCommand([main['AS'], '-v', '/dev/null'],
603                                 exception=False).split()
604
605        if not as_version or compareVersions(as_version[-1], "2.23") < 0:
606            print termcap.Yellow + termcap.Bold + \
607                'Warning: This combination of gcc and binutils have' + \
608                ' known incompatibilities.\n' + \
609                '         If you encounter build problems, please update ' + \
610                'binutils to 2.23.' + \
611                termcap.Normal
612
613    # Make sure we warn if the user has requested to compile with the
614    # Undefined Benahvior Sanitizer and this version of gcc does not
615    # support it.
616    if GetOption('with_ubsan') and \
617            compareVersions(gcc_version, '4.9') < 0:
618        print termcap.Yellow + termcap.Bold + \
619            'Warning: UBSan is only supported using gcc 4.9 and later.' + \
620            termcap.Normal
621
622    # Add the appropriate Link-Time Optimization (LTO) flags
623    # unless LTO is explicitly turned off. Note that these flags
624    # are only used by the fast target.
625    if not GetOption('no_lto'):
626        # Pass the LTO flag when compiling to produce GIMPLE
627        # output, we merely create the flags here and only append
628        # them later
629        main['LTO_CCFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
630
631        # Use the same amount of jobs for LTO as we are running
632        # scons with
633        main['LTO_LDFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
634
635    main.Append(TCMALLOC_CCFLAGS=['-fno-builtin-malloc', '-fno-builtin-calloc',
636                                  '-fno-builtin-realloc', '-fno-builtin-free'])
637
638elif main['CLANG']:
639    # Check for a supported version of clang, >= 3.0 is needed to
640    # support similar features as gcc 4.6. See
641    # http://clang.llvm.org/cxx_status.html for details
642    clang_version_re = re.compile(".* version (\d+\.\d+)")
643    clang_version_match = clang_version_re.search(CXX_version)
644    if (clang_version_match):
645        clang_version = clang_version_match.groups()[0]
646        if compareVersions(clang_version, "3.0") < 0:
647            print 'Error: clang version 3.0 or newer required.'
648            print '       Installed version:', clang_version
649            Exit(1)
650    else:
651        print 'Error: Unable to determine clang version.'
652        Exit(1)
653
654    # clang has a few additional warnings that we disable,
655    # tautological comparisons are allowed due to unsigned integers
656    # being compared to constants that happen to be 0, and extraneous
657    # parantheses are allowed due to Ruby's printing of the AST,
658    # finally self assignments are allowed as the generated CPU code
659    # is relying on this
660    main.Append(CCFLAGS=['-Wno-tautological-compare',
661                         '-Wno-parentheses',
662                         '-Wno-self-assign',
663                         # Some versions of libstdc++ (4.8?) seem to
664                         # use struct hash and class hash
665                         # interchangeably.
666                         '-Wno-mismatched-tags',
667                         ])
668
669    main.Append(TCMALLOC_CCFLAGS=['-fno-builtin'])
670
671    # On Mac OS X/Darwin we need to also use libc++ (part of XCode) as
672    # opposed to libstdc++, as the later is dated.
673    if sys.platform == "darwin":
674        main.Append(CXXFLAGS=['-stdlib=libc++'])
675        main.Append(LIBS=['c++'])
676
677else:
678    print termcap.Yellow + termcap.Bold + 'Error' + termcap.Normal,
679    print "Don't know what compiler options to use for your compiler."
680    print termcap.Yellow + '       compiler:' + termcap.Normal, main['CXX']
681    print termcap.Yellow + '       version:' + termcap.Normal,
682    if not CXX_version:
683        print termcap.Yellow + termcap.Bold + "COMMAND NOT FOUND!" +\
684               termcap.Normal
685    else:
686        print CXX_version.replace('\n', '<nl>')
687    print "       If you're trying to use a compiler other than GCC"
688    print "       or clang, there appears to be something wrong with your"
689    print "       environment."
690    print "       "
691    print "       If you are trying to use a compiler other than those listed"
692    print "       above you will need to ease fix SConstruct and "
693    print "       src/SConscript to support that compiler."
694    Exit(1)
695
696# Set up common yacc/bison flags (needed for Ruby)
697main['YACCFLAGS'] = '-d'
698main['YACCHXXFILESUFFIX'] = '.hh'
699
700# Do this after we save setting back, or else we'll tack on an
701# extra 'qdo' every time we run scons.
702if main['BATCH']:
703    main['CC']     = main['BATCH_CMD'] + ' ' + main['CC']
704    main['CXX']    = main['BATCH_CMD'] + ' ' + main['CXX']
705    main['AS']     = main['BATCH_CMD'] + ' ' + main['AS']
706    main['AR']     = main['BATCH_CMD'] + ' ' + main['AR']
707    main['RANLIB'] = main['BATCH_CMD'] + ' ' + main['RANLIB']
708
709if sys.platform == 'cygwin':
710    # cygwin has some header file issues...
711    main.Append(CCFLAGS=["-Wno-uninitialized"])
712
713# Check for the protobuf compiler
714protoc_version = readCommand([main['PROTOC'], '--version'],
715                             exception='').split()
716
717# First two words should be "libprotoc x.y.z"
718if len(protoc_version) < 2 or protoc_version[0] != 'libprotoc':
719    print termcap.Yellow + termcap.Bold + \
720        'Warning: Protocol buffer compiler (protoc) not found.\n' + \
721        '         Please install protobuf-compiler for tracing support.' + \
722        termcap.Normal
723    main['PROTOC'] = False
724else:
725    # Based on the availability of the compress stream wrappers,
726    # require 2.1.0
727    min_protoc_version = '2.1.0'
728    if compareVersions(protoc_version[1], min_protoc_version) < 0:
729        print termcap.Yellow + termcap.Bold + \
730            'Warning: protoc version', min_protoc_version, \
731            'or newer required.\n' + \
732            '         Installed version:', protoc_version[1], \
733            termcap.Normal
734        main['PROTOC'] = False
735    else:
736        # Attempt to determine the appropriate include path and
737        # library path using pkg-config, that means we also need to
738        # check for pkg-config. Note that it is possible to use
739        # protobuf without the involvement of pkg-config. Later on we
740        # check go a library config check and at that point the test
741        # will fail if libprotobuf cannot be found.
742        if readCommand(['pkg-config', '--version'], exception=''):
743            try:
744                # Attempt to establish what linking flags to add for protobuf
745                # using pkg-config
746                main.ParseConfig('pkg-config --cflags --libs-only-L protobuf')
747            except:
748                print termcap.Yellow + termcap.Bold + \
749                    'Warning: pkg-config could not get protobuf flags.' + \
750                    termcap.Normal
751
752# Check for SWIG
753if not main.has_key('SWIG'):
754    print 'Error: SWIG utility not found.'
755    print '       Please install (see http://www.swig.org) and retry.'
756    Exit(1)
757
758# Check for appropriate SWIG version
759swig_version = readCommand([main['SWIG'], '-version'], exception='').split()
760# First 3 words should be "SWIG Version x.y.z"
761if len(swig_version) < 3 or \
762        swig_version[0] != 'SWIG' or swig_version[1] != 'Version':
763    print 'Error determining SWIG version.'
764    Exit(1)
765
766min_swig_version = '2.0.4'
767if compareVersions(swig_version[2], min_swig_version) < 0:
768    print 'Error: SWIG version', min_swig_version, 'or newer required.'
769    print '       Installed version:', swig_version[2]
770    Exit(1)
771
772# Check for known incompatibilities. The standard library shipped with
773# gcc >= 4.9 does not play well with swig versions prior to 3.0
774if main['GCC'] and compareVersions(gcc_version, '4.9') >= 0 and \
775        compareVersions(swig_version[2], '3.0') < 0:
776    print termcap.Yellow + termcap.Bold + \
777        'Warning: This combination of gcc and swig have' + \
778        ' known incompatibilities.\n' + \
779        '         If you encounter build problems, please update ' + \
780        'swig to 3.0 or later.' + \
781        termcap.Normal
782
783# Set up SWIG flags & scanner
784swig_flags=Split('-c++ -python -modern -templatereduce $_CPPINCFLAGS')
785main.Append(SWIGFLAGS=swig_flags)
786
787# Check for 'timeout' from GNU coreutils. If present, regressions will
788# be run with a time limit. We require version 8.13 since we rely on
789# support for the '--foreground' option.
790timeout_lines = readCommand(['timeout', '--version'],
791                            exception='').splitlines()
792# Get the first line and tokenize it
793timeout_version = timeout_lines[0].split() if timeout_lines else []
794main['TIMEOUT'] =  timeout_version and \
795    compareVersions(timeout_version[-1], '8.13') >= 0
796
797# filter out all existing swig scanners, they mess up the dependency
798# stuff for some reason
799scanners = []
800for scanner in main['SCANNERS']:
801    skeys = scanner.skeys
802    if skeys == '.i':
803        continue
804
805    if isinstance(skeys, (list, tuple)) and '.i' in skeys:
806        continue
807
808    scanners.append(scanner)
809
810# add the new swig scanner that we like better
811from SCons.Scanner import ClassicCPP as CPPScanner
812swig_inc_re = '^[ \t]*[%,#][ \t]*(?:include|import)[ \t]*(<|")([^>"]+)(>|")'
813scanners.append(CPPScanner("SwigScan", [ ".i" ], "CPPPATH", swig_inc_re))
814
815# replace the scanners list that has what we want
816main['SCANNERS'] = scanners
817
818# Add a custom Check function to the Configure context so that we can
819# figure out if the compiler adds leading underscores to global
820# variables.  This is needed for the autogenerated asm files that we
821# use for embedding the python code.
822def CheckLeading(context):
823    context.Message("Checking for leading underscore in global variables...")
824    # 1) Define a global variable called x from asm so the C compiler
825    #    won't change the symbol at all.
826    # 2) Declare that variable.
827    # 3) Use the variable
828    #
829    # If the compiler prepends an underscore, this will successfully
830    # link because the external symbol 'x' will be called '_x' which
831    # was defined by the asm statement.  If the compiler does not
832    # prepend an underscore, this will not successfully link because
833    # '_x' will have been defined by assembly, while the C portion of
834    # the code will be trying to use 'x'
835    ret = context.TryLink('''
836        asm(".globl _x; _x: .byte 0");
837        extern int x;
838        int main() { return x; }
839        ''', extension=".c")
840    context.env.Append(LEADING_UNDERSCORE=ret)
841    context.Result(ret)
842    return ret
843
844# Add a custom Check function to test for structure members.
845def CheckMember(context, include, decl, member, include_quotes="<>"):
846    context.Message("Checking for member %s in %s..." %
847                    (member, decl))
848    text = """
849#include %(header)s
850int main(){
851  %(decl)s test;
852  (void)test.%(member)s;
853  return 0;
854};
855""" % { "header" : include_quotes[0] + include + include_quotes[1],
856        "decl" : decl,
857        "member" : member,
858        }
859
860    ret = context.TryCompile(text, extension=".cc")
861    context.Result(ret)
862    return ret
863
864# Platform-specific configuration.  Note again that we assume that all
865# builds under a given build root run on the same host platform.
866conf = Configure(main,
867                 conf_dir = joinpath(build_root, '.scons_config'),
868                 log_file = joinpath(build_root, 'scons_config.log'),
869                 custom_tests = {
870        'CheckLeading' : CheckLeading,
871        'CheckMember' : CheckMember,
872        })
873
874# Check for leading underscores.  Don't really need to worry either
875# way so don't need to check the return code.
876conf.CheckLeading()
877
878# Check if we should compile a 64 bit binary on Mac OS X/Darwin
879try:
880    import platform
881    uname = platform.uname()
882    if uname[0] == 'Darwin' and compareVersions(uname[2], '9.0.0') >= 0:
883        if int(readCommand('sysctl -n hw.cpu64bit_capable')[0]):
884            main.Append(CCFLAGS=['-arch', 'x86_64'])
885            main.Append(CFLAGS=['-arch', 'x86_64'])
886            main.Append(LINKFLAGS=['-arch', 'x86_64'])
887            main.Append(ASFLAGS=['-arch', 'x86_64'])
888except:
889    pass
890
891# Recent versions of scons substitute a "Null" object for Configure()
892# when configuration isn't necessary, e.g., if the "--help" option is
893# present.  Unfortuantely this Null object always returns false,
894# breaking all our configuration checks.  We replace it with our own
895# more optimistic null object that returns True instead.
896if not conf:
897    def NullCheck(*args, **kwargs):
898        return True
899
900    class NullConf:
901        def __init__(self, env):
902            self.env = env
903        def Finish(self):
904            return self.env
905        def __getattr__(self, mname):
906            return NullCheck
907
908    conf = NullConf(main)
909
910# Cache build files in the supplied directory.
911if main['M5_BUILD_CACHE']:
912    print 'Using build cache located at', main['M5_BUILD_CACHE']
913    CacheDir(main['M5_BUILD_CACHE'])
914
915if not GetOption('without_python'):
916    # Find Python include and library directories for embedding the
917    # interpreter. We rely on python-config to resolve the appropriate
918    # includes and linker flags. ParseConfig does not seem to understand
919    # the more exotic linker flags such as -Xlinker and -export-dynamic so
920    # we add them explicitly below. If you want to link in an alternate
921    # version of python, see above for instructions on how to invoke
922    # scons with the appropriate PATH set.
923    #
924    # First we check if python2-config exists, else we use python-config
925    python_config = readCommand(['which', 'python2-config'],
926                                exception='').strip()
927    if not os.path.exists(python_config):
928        python_config = readCommand(['which', 'python-config'],
929                                    exception='').strip()
930    py_includes = readCommand([python_config, '--includes'],
931                              exception='').split()
932    # Strip the -I from the include folders before adding them to the
933    # CPPPATH
934    main.Append(CPPPATH=map(lambda inc: inc[2:], py_includes))
935
936    # Read the linker flags and split them into libraries and other link
937    # flags. The libraries are added later through the call the CheckLib.
938    py_ld_flags = readCommand([python_config, '--ldflags'],
939        exception='').split()
940    py_libs = []
941    for lib in py_ld_flags:
942         if not lib.startswith('-l'):
943             main.Append(LINKFLAGS=[lib])
944         else:
945             lib = lib[2:]
946             if lib not in py_libs:
947                 py_libs.append(lib)
948
949    # verify that this stuff works
950    if not conf.CheckHeader('Python.h', '<>'):
951        print "Error: can't find Python.h header in", py_includes
952        print "Install Python headers (package python-dev on Ubuntu and RedHat)"
953        Exit(1)
954
955    for lib in py_libs:
956        if not conf.CheckLib(lib):
957            print "Error: can't find library %s required by python" % lib
958            Exit(1)
959
960# On Solaris you need to use libsocket for socket ops
961if not conf.CheckLibWithHeader(None, 'sys/socket.h', 'C++', 'accept(0,0,0);'):
962   if not conf.CheckLibWithHeader('socket', 'sys/socket.h', 'C++', 'accept(0,0,0);'):
963       print "Can't find library with socket calls (e.g. accept())"
964       Exit(1)
965
966# Check for zlib.  If the check passes, libz will be automatically
967# added to the LIBS environment variable.
968if not conf.CheckLibWithHeader('z', 'zlib.h', 'C++','zlibVersion();'):
969    print 'Error: did not find needed zlib compression library '\
970          'and/or zlib.h header file.'
971    print '       Please install zlib and try again.'
972    Exit(1)
973
974# If we have the protobuf compiler, also make sure we have the
975# development libraries. If the check passes, libprotobuf will be
976# automatically added to the LIBS environment variable. After
977# this, we can use the HAVE_PROTOBUF flag to determine if we have
978# got both protoc and libprotobuf available.
979main['HAVE_PROTOBUF'] = main['PROTOC'] and \
980    conf.CheckLibWithHeader('protobuf', 'google/protobuf/message.h',
981                            'C++', 'GOOGLE_PROTOBUF_VERIFY_VERSION;')
982
983# If we have the compiler but not the library, print another warning.
984if main['PROTOC'] and not main['HAVE_PROTOBUF']:
985    print termcap.Yellow + termcap.Bold + \
986        'Warning: did not find protocol buffer library and/or headers.\n' + \
987    '       Please install libprotobuf-dev for tracing support.' + \
988    termcap.Normal
989
990# Check for librt.
991have_posix_clock = \
992    conf.CheckLibWithHeader(None, 'time.h', 'C',
993                            'clock_nanosleep(0,0,NULL,NULL);') or \
994    conf.CheckLibWithHeader('rt', 'time.h', 'C',
995                            'clock_nanosleep(0,0,NULL,NULL);')
996
997have_posix_timers = \
998    conf.CheckLibWithHeader([None, 'rt'], [ 'time.h', 'signal.h' ], 'C',
999                            'timer_create(CLOCK_MONOTONIC, NULL, NULL);')
1000
1001if not GetOption('without_tcmalloc'):
1002    if conf.CheckLib('tcmalloc'):
1003        main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
1004    elif conf.CheckLib('tcmalloc_minimal'):
1005        main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
1006    else:
1007        print termcap.Yellow + termcap.Bold + \
1008              "You can get a 12% performance improvement by "\
1009              "installing tcmalloc (libgoogle-perftools-dev package "\
1010              "on Ubuntu or RedHat)." + termcap.Normal
1011
1012if not have_posix_clock:
1013    print "Can't find library for POSIX clocks."
1014
1015# Check for <fenv.h> (C99 FP environment control)
1016have_fenv = conf.CheckHeader('fenv.h', '<>')
1017if not have_fenv:
1018    print "Warning: Header file <fenv.h> not found."
1019    print "         This host has no IEEE FP rounding mode control."
1020
1021# Check if we should enable KVM-based hardware virtualization. The API
1022# we rely on exists since version 2.6.36 of the kernel, but somehow
1023# the KVM_API_VERSION does not reflect the change. We test for one of
1024# the types as a fall back.
1025have_kvm = conf.CheckHeader('linux/kvm.h', '<>')
1026if not have_kvm:
1027    print "Info: Compatible header file <linux/kvm.h> not found, " \
1028        "disabling KVM support."
1029
1030# x86 needs support for xsave. We test for the structure here since we
1031# won't be able to run new tests by the time we know which ISA we're
1032# targeting.
1033have_kvm_xsave = conf.CheckTypeSize('struct kvm_xsave',
1034                                    '#include <linux/kvm.h>') != 0
1035
1036# Check if the requested target ISA is compatible with the host
1037def is_isa_kvm_compatible(isa):
1038    try:
1039        import platform
1040        host_isa = platform.machine()
1041    except:
1042        print "Warning: Failed to determine host ISA."
1043        return False
1044
1045    if not have_posix_timers:
1046        print "Warning: Can not enable KVM, host seems to lack support " \
1047            "for POSIX timers"
1048        return False
1049
1050    if isa == "arm":
1051        return host_isa == "armv7l"
1052    elif isa == "x86":
1053        if host_isa != "x86_64":
1054            return False
1055
1056        if not have_kvm_xsave:
1057            print "KVM on x86 requires xsave support in kernel headers."
1058            return False
1059
1060        return True
1061    else:
1062        return False
1063
1064
1065# Check if the exclude_host attribute is available. We want this to
1066# get accurate instruction counts in KVM.
1067main['HAVE_PERF_ATTR_EXCLUDE_HOST'] = conf.CheckMember(
1068    'linux/perf_event.h', 'struct perf_event_attr', 'exclude_host')
1069
1070
1071######################################################################
1072#
1073# Finish the configuration
1074#
1075main = conf.Finish()
1076
1077######################################################################
1078#
1079# Collect all non-global variables
1080#
1081
1082# Define the universe of supported ISAs
1083all_isa_list = [ ]
1084Export('all_isa_list')
1085
1086class CpuModel(object):
1087    '''The CpuModel class encapsulates everything the ISA parser needs to
1088    know about a particular CPU model.'''
1089
1090    # Dict of available CPU model objects.  Accessible as CpuModel.dict.
1091    dict = {}
1092
1093    # Constructor.  Automatically adds models to CpuModel.dict.
1094    def __init__(self, name, default=False):
1095        self.name = name           # name of model
1096
1097        # This cpu is enabled by default
1098        self.default = default
1099
1100        # Add self to dict
1101        if name in CpuModel.dict:
1102            raise AttributeError, "CpuModel '%s' already registered" % name
1103        CpuModel.dict[name] = self
1104
1105Export('CpuModel')
1106
1107# Sticky variables get saved in the variables file so they persist from
1108# one invocation to the next (unless overridden, in which case the new
1109# value becomes sticky).
1110sticky_vars = Variables(args=ARGUMENTS)
1111Export('sticky_vars')
1112
1113# Sticky variables that should be exported
1114export_vars = []
1115Export('export_vars')
1116
1117# For Ruby
1118all_protocols = []
1119Export('all_protocols')
1120protocol_dirs = []
1121Export('protocol_dirs')
1122slicc_includes = []
1123Export('slicc_includes')
1124
1125# Walk the tree and execute all SConsopts scripts that wil add to the
1126# above variables
1127if GetOption('verbose'):
1128    print "Reading SConsopts"
1129for bdir in [ base_dir ] + extras_dir_list:
1130    if not isdir(bdir):
1131        print "Error: directory '%s' does not exist" % bdir
1132        Exit(1)
1133    for root, dirs, files in os.walk(bdir):
1134        if 'SConsopts' in files:
1135            if GetOption('verbose'):
1136                print "Reading", joinpath(root, 'SConsopts')
1137            SConscript(joinpath(root, 'SConsopts'))
1138
1139all_isa_list.sort()
1140
1141sticky_vars.AddVariables(
1142    EnumVariable('TARGET_ISA', 'Target ISA', 'alpha', all_isa_list),
1143    ListVariable('CPU_MODELS', 'CPU models',
1144                 sorted(n for n,m in CpuModel.dict.iteritems() if m.default),
1145                 sorted(CpuModel.dict.keys())),
1146    BoolVariable('EFENCE', 'Link with Electric Fence malloc debugger',
1147                 False),
1148    BoolVariable('SS_COMPATIBLE_FP',
1149                 'Make floating-point results compatible with SimpleScalar',
1150                 False),
1151    BoolVariable('USE_SSE2',
1152                 'Compile for SSE2 (-msse2) to get IEEE FP on x86 hosts',
1153                 False),
1154    BoolVariable('USE_POSIX_CLOCK', 'Use POSIX Clocks', have_posix_clock),
1155    BoolVariable('USE_FENV', 'Use <fenv.h> IEEE mode control', have_fenv),
1156    BoolVariable('CP_ANNOTATE', 'Enable critical path annotation capability', False),
1157    BoolVariable('USE_KVM', 'Enable hardware virtualized (KVM) CPU models', have_kvm),
1158    EnumVariable('PROTOCOL', 'Coherence protocol for Ruby', 'None',
1159                  all_protocols),
1160    )
1161
1162# These variables get exported to #defines in config/*.hh (see src/SConscript).
1163export_vars += ['USE_FENV', 'SS_COMPATIBLE_FP', 'TARGET_ISA', 'CP_ANNOTATE',
1164                'USE_POSIX_CLOCK', 'USE_KVM', 'PROTOCOL', 'HAVE_PROTOBUF',
1165                'HAVE_PERF_ATTR_EXCLUDE_HOST']
1166
1167###################################################
1168#
1169# Define a SCons builder for configuration flag headers.
1170#
1171###################################################
1172
1173# This function generates a config header file that #defines the
1174# variable symbol to the current variable setting (0 or 1).  The source
1175# operands are the name of the variable and a Value node containing the
1176# value of the variable.
1177def build_config_file(target, source, env):
1178    (variable, value) = [s.get_contents() for s in source]
1179    f = file(str(target[0]), 'w')
1180    print >> f, '#define', variable, value
1181    f.close()
1182    return None
1183
1184# Combine the two functions into a scons Action object.
1185config_action = MakeAction(build_config_file, Transform("CONFIG H", 2))
1186
1187# The emitter munges the source & target node lists to reflect what
1188# we're really doing.
1189def config_emitter(target, source, env):
1190    # extract variable name from Builder arg
1191    variable = str(target[0])
1192    # True target is config header file
1193    target = joinpath('config', variable.lower() + '.hh')
1194    val = env[variable]
1195    if isinstance(val, bool):
1196        # Force value to 0/1
1197        val = int(val)
1198    elif isinstance(val, str):
1199        val = '"' + val + '"'
1200
1201    # Sources are variable name & value (packaged in SCons Value nodes)
1202    return ([target], [Value(variable), Value(val)])
1203
1204config_builder = Builder(emitter = config_emitter, action = config_action)
1205
1206main.Append(BUILDERS = { 'ConfigFile' : config_builder })
1207
1208# libelf build is shared across all configs in the build root.
1209main.SConscript('ext/libelf/SConscript',
1210                variant_dir = joinpath(build_root, 'libelf'))
1211
1212# gzstream build is shared across all configs in the build root.
1213main.SConscript('ext/gzstream/SConscript',
1214                variant_dir = joinpath(build_root, 'gzstream'))
1215
1216# libfdt build is shared across all configs in the build root.
1217main.SConscript('ext/libfdt/SConscript',
1218                variant_dir = joinpath(build_root, 'libfdt'))
1219
1220# fputils build is shared across all configs in the build root.
1221main.SConscript('ext/fputils/SConscript',
1222                variant_dir = joinpath(build_root, 'fputils'))
1223
1224# DRAMSim2 build is shared across all configs in the build root.
1225main.SConscript('ext/dramsim2/SConscript',
1226                variant_dir = joinpath(build_root, 'dramsim2'))
1227
1228# DRAMPower build is shared across all configs in the build root.
1229main.SConscript('ext/drampower/SConscript',
1230                variant_dir = joinpath(build_root, 'drampower'))
1231
1232###################################################
1233#
1234# This function is used to set up a directory with switching headers
1235#
1236###################################################
1237
1238main['ALL_ISA_LIST'] = all_isa_list
1239all_isa_deps = {}
1240def make_switching_dir(dname, switch_headers, env):
1241    # Generate the header.  target[0] is the full path of the output
1242    # header to generate.  'source' is a dummy variable, since we get the
1243    # list of ISAs from env['ALL_ISA_LIST'].
1244    def gen_switch_hdr(target, source, env):
1245        fname = str(target[0])
1246        isa = env['TARGET_ISA'].lower()
1247        try:
1248            f = open(fname, 'w')
1249            print >>f, '#include "%s/%s/%s"' % (dname, isa, basename(fname))
1250            f.close()
1251        except IOError:
1252            print "Failed to create %s" % fname
1253            raise
1254
1255    # Build SCons Action object. 'varlist' specifies env vars that this
1256    # action depends on; when env['ALL_ISA_LIST'] changes these actions
1257    # should get re-executed.
1258    switch_hdr_action = MakeAction(gen_switch_hdr,
1259                          Transform("GENERATE"), varlist=['ALL_ISA_LIST'])
1260
1261    # Instantiate actions for each header
1262    for hdr in switch_headers:
1263        env.Command(hdr, [], switch_hdr_action)
1264
1265    isa_target = Dir('.').up().name.lower().replace('_', '-')
1266    env['PHONY_BASE'] = '#'+isa_target
1267    all_isa_deps[isa_target] = None
1268
1269Export('make_switching_dir')
1270
1271# all-isas -> all-deps -> all-environs -> all_targets
1272main.Alias('#all-isas', [])
1273main.Alias('#all-deps', '#all-isas')
1274
1275# Dummy target to ensure all environments are created before telling
1276# SCons what to actually make (the command line arguments).  We attach
1277# them to the dependence graph after the environments are complete.
1278ORIG_BUILD_TARGETS = list(BUILD_TARGETS) # force a copy; gets closure to work.
1279def environsComplete(target, source, env):
1280    for t in ORIG_BUILD_TARGETS:
1281        main.Depends('#all-targets', t)
1282
1283# Each build/* switching_dir attaches its *-environs target to #all-environs.
1284main.Append(BUILDERS = {'CompleteEnvirons' :
1285                        Builder(action=MakeAction(environsComplete, None))})
1286main.CompleteEnvirons('#all-environs', [])
1287
1288def doNothing(**ignored): pass
1289main.Append(BUILDERS = {'Dummy': Builder(action=MakeAction(doNothing, None))})
1290
1291# The final target to which all the original targets ultimately get attached.
1292main.Dummy('#all-targets', '#all-environs')
1293BUILD_TARGETS[:] = ['#all-targets']
1294
1295###################################################
1296#
1297# Define build environments for selected configurations.
1298#
1299###################################################
1300
1301for variant_path in variant_paths:
1302    if not GetOption('silent'):
1303        print "Building in", variant_path
1304
1305    # Make a copy of the build-root environment to use for this config.
1306    env = main.Clone()
1307    env['BUILDDIR'] = variant_path
1308
1309    # variant_dir is the tail component of build path, and is used to
1310    # determine the build parameters (e.g., 'ALPHA_SE')
1311    (build_root, variant_dir) = splitpath(variant_path)
1312
1313    # Set env variables according to the build directory config.
1314    sticky_vars.files = []
1315    # Variables for $BUILD_ROOT/$VARIANT_DIR are stored in
1316    # $BUILD_ROOT/variables/$VARIANT_DIR so you can nuke
1317    # $BUILD_ROOT/$VARIANT_DIR without losing your variables settings.
1318    current_vars_file = joinpath(build_root, 'variables', variant_dir)
1319    if isfile(current_vars_file):
1320        sticky_vars.files.append(current_vars_file)
1321        if not GetOption('silent'):
1322            print "Using saved variables file %s" % current_vars_file
1323    else:
1324        # Build dir-specific variables file doesn't exist.
1325
1326        # Make sure the directory is there so we can create it later
1327        opt_dir = dirname(current_vars_file)
1328        if not isdir(opt_dir):
1329            mkdir(opt_dir)
1330
1331        # Get default build variables from source tree.  Variables are
1332        # normally determined by name of $VARIANT_DIR, but can be
1333        # overridden by '--default=' arg on command line.
1334        default = GetOption('default')
1335        opts_dir = joinpath(main.root.abspath, 'build_opts')
1336        if default:
1337            default_vars_files = [joinpath(build_root, 'variables', default),
1338                                  joinpath(opts_dir, default)]
1339        else:
1340            default_vars_files = [joinpath(opts_dir, variant_dir)]
1341        existing_files = filter(isfile, default_vars_files)
1342        if existing_files:
1343            default_vars_file = existing_files[0]
1344            sticky_vars.files.append(default_vars_file)
1345            print "Variables file %s not found,\n  using defaults in %s" \
1346                  % (current_vars_file, default_vars_file)
1347        else:
1348            print "Error: cannot find variables file %s or " \
1349                  "default file(s) %s" \
1350                  % (current_vars_file, ' or '.join(default_vars_files))
1351            Exit(1)
1352
1353    # Apply current variable settings to env
1354    sticky_vars.Update(env)
1355
1356    help_texts["local_vars"] += \
1357        "Build variables for %s:\n" % variant_dir \
1358                 + sticky_vars.GenerateHelpText(env)
1359
1360    # Process variable settings.
1361
1362    if not have_fenv and env['USE_FENV']:
1363        print "Warning: <fenv.h> not available; " \
1364              "forcing USE_FENV to False in", variant_dir + "."
1365        env['USE_FENV'] = False
1366
1367    if not env['USE_FENV']:
1368        print "Warning: No IEEE FP rounding mode control in", variant_dir + "."
1369        print "         FP results may deviate slightly from other platforms."
1370
1371    if env['EFENCE']:
1372        env.Append(LIBS=['efence'])
1373
1374    if env['USE_KVM']:
1375        if not have_kvm:
1376            print "Warning: Can not enable KVM, host seems to lack KVM support"
1377            env['USE_KVM'] = False
1378        elif not is_isa_kvm_compatible(env['TARGET_ISA']):
1379            print "Info: KVM support disabled due to unsupported host and " \
1380                "target ISA combination"
1381            env['USE_KVM'] = False
1382
1383    # Warn about missing optional functionality
1384    if env['USE_KVM']:
1385        if not main['HAVE_PERF_ATTR_EXCLUDE_HOST']:
1386            print "Warning: perf_event headers lack support for the " \
1387                "exclude_host attribute. KVM instruction counts will " \
1388                "be inaccurate."
1389
1390    # Save sticky variable settings back to current variables file
1391    sticky_vars.Save(current_vars_file, env)
1392
1393    if env['USE_SSE2']:
1394        env.Append(CCFLAGS=['-msse2'])
1395
1396    # The src/SConscript file sets up the build rules in 'env' according
1397    # to the configured variables.  It returns a list of environments,
1398    # one for each variant build (debug, opt, etc.)
1399    SConscript('src/SConscript', variant_dir = variant_path, exports = 'env')
1400
1401def pairwise(iterable):
1402    "s -> (s0,s1), (s1,s2), (s2, s3), ..."
1403    a, b = itertools.tee(iterable)
1404    b.next()
1405    return itertools.izip(a, b)
1406
1407# Create false dependencies so SCons will parse ISAs, establish
1408# dependencies, and setup the build Environments serially. Either
1409# SCons (likely) and/or our SConscripts (possibly) cannot cope with -j
1410# greater than 1. It appears to be standard race condition stuff; it
1411# doesn't always fail, but usually, and the behaviors are different.
1412# Every time I tried to remove this, builds would fail in some
1413# creative new way. So, don't do that. You'll want to, though, because
1414# tests/SConscript takes a long time to make its Environments.
1415for t1, t2 in pairwise(sorted(all_isa_deps.iterkeys())):
1416    main.Depends('#%s-deps'     % t2, '#%s-deps'     % t1)
1417    main.Depends('#%s-environs' % t2, '#%s-environs' % t1)
1418
1419# base help text
1420Help('''
1421Usage: scons [scons options] [build variables] [target(s)]
1422
1423Extra scons options:
1424%(options)s
1425
1426Global build variables:
1427%(global_vars)s
1428
1429%(local_vars)s
1430''' % help_texts)
1431