SConstruct revision 11927
1# -*- mode:python -*-
2
3# Copyright (c) 2013, 2015, 2016 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 shutil
116import subprocess
117import sys
118
119from os import mkdir, environ
120from os.path import abspath, basename, dirname, expanduser, normpath
121from os.path import exists,  isdir, isfile
122from os.path import join as joinpath, split as splitpath
123
124# SCons includes
125import SCons
126import SCons.Node
127
128extra_python_paths = [
129    Dir('src/python').srcnode().abspath, # gem5 includes
130    Dir('ext/ply').srcnode().abspath, # ply is used by several files
131    ]
132
133sys.path[1:1] = extra_python_paths
134
135from m5.util import compareVersions, readCommand
136from m5.util.terminal import get_termcap
137
138help_texts = {
139    "options" : "",
140    "global_vars" : "",
141    "local_vars" : ""
142}
143
144Export("help_texts")
145
146
147# There's a bug in scons in that (1) by default, the help texts from
148# AddOption() are supposed to be displayed when you type 'scons -h'
149# and (2) you can override the help displayed by 'scons -h' using the
150# Help() function, but these two features are incompatible: once
151# you've overridden the help text using Help(), there's no way to get
152# at the help texts from AddOptions.  See:
153#     http://scons.tigris.org/issues/show_bug.cgi?id=2356
154#     http://scons.tigris.org/issues/show_bug.cgi?id=2611
155# This hack lets us extract the help text from AddOptions and
156# re-inject it via Help().  Ideally someday this bug will be fixed and
157# we can just use AddOption directly.
158def AddLocalOption(*args, **kwargs):
159    col_width = 30
160
161    help = "  " + ", ".join(args)
162    if "help" in kwargs:
163        length = len(help)
164        if length >= col_width:
165            help += "\n" + " " * col_width
166        else:
167            help += " " * (col_width - length)
168        help += kwargs["help"]
169    help_texts["options"] += help + "\n"
170
171    AddOption(*args, **kwargs)
172
173AddLocalOption('--colors', dest='use_colors', action='store_true',
174               help="Add color to abbreviated scons output")
175AddLocalOption('--no-colors', dest='use_colors', action='store_false',
176               help="Don't add color to abbreviated scons output")
177AddLocalOption('--with-cxx-config', dest='with_cxx_config',
178               action='store_true',
179               help="Build with support for C++-based configuration")
180AddLocalOption('--default', dest='default', type='string', action='store',
181               help='Override which build_opts file to use for defaults')
182AddLocalOption('--ignore-style', dest='ignore_style', action='store_true',
183               help='Disable style checking hooks')
184AddLocalOption('--no-lto', dest='no_lto', action='store_true',
185               help='Disable Link-Time Optimization for fast')
186AddLocalOption('--update-ref', dest='update_ref', action='store_true',
187               help='Update test reference outputs')
188AddLocalOption('--verbose', dest='verbose', action='store_true',
189               help='Print full tool command lines')
190AddLocalOption('--without-python', dest='without_python',
191               action='store_true',
192               help='Build without Python configuration support')
193AddLocalOption('--without-tcmalloc', dest='without_tcmalloc',
194               action='store_true',
195               help='Disable linking against tcmalloc')
196AddLocalOption('--with-ubsan', dest='with_ubsan', action='store_true',
197               help='Build with Undefined Behavior Sanitizer if available')
198AddLocalOption('--with-asan', dest='with_asan', action='store_true',
199               help='Build with Address Sanitizer if available')
200
201termcap = get_termcap(GetOption('use_colors'))
202
203########################################################################
204#
205# Set up the main build environment.
206#
207########################################################################
208
209# export TERM so that clang reports errors in color
210use_vars = set([ 'AS', 'AR', 'CC', 'CXX', 'HOME', 'LD_LIBRARY_PATH',
211                 'LIBRARY_PATH', 'PATH', 'PKG_CONFIG_PATH', 'PROTOC',
212                 'PYTHONPATH', 'RANLIB', 'SWIG', 'TERM' ])
213
214use_prefixes = [
215    "ASAN_",           # address sanitizer symbolizer path and settings
216    "CCACHE_",         # ccache (caching compiler wrapper) configuration
217    "CCC_",            # clang static analyzer configuration
218    "DISTCC_",         # distcc (distributed compiler wrapper) configuration
219    "INCLUDE_SERVER_", # distcc pump server settings
220    "M5",              # M5 configuration (e.g., path to kernels)
221    ]
222
223use_env = {}
224for key,val in sorted(os.environ.iteritems()):
225    if key in use_vars or \
226            any([key.startswith(prefix) for prefix in use_prefixes]):
227        use_env[key] = val
228
229# Tell scons to avoid implicit command dependencies to avoid issues
230# with the param wrappes being compiled twice (see
231# http://scons.tigris.org/issues/show_bug.cgi?id=2811)
232main = Environment(ENV=use_env, IMPLICIT_COMMAND_DEPENDENCIES=0)
233main.Decider('MD5-timestamp')
234main.root = Dir(".")         # The current directory (where this file lives).
235main.srcdir = Dir("src")     # The source directory
236
237main_dict_keys = main.Dictionary().keys()
238
239# Check that we have a C/C++ compiler
240if not ('CC' in main_dict_keys and 'CXX' in main_dict_keys):
241    print "No C++ compiler installed (package g++ on Ubuntu and RedHat)"
242    Exit(1)
243
244# Check that swig is present
245if not 'SWIG' in main_dict_keys:
246    print "swig is not installed (package swig on Ubuntu and RedHat)"
247    Exit(1)
248
249# add useful python code PYTHONPATH so it can be used by subprocesses
250# as well
251main.AppendENVPath('PYTHONPATH', extra_python_paths)
252
253########################################################################
254#
255# Mercurial Stuff.
256#
257# If the gem5 directory is a mercurial repository, we should do some
258# extra things.
259#
260########################################################################
261
262hgdir = main.root.Dir(".hg")
263
264
265style_message = """
266You're missing the gem5 style hook, which automatically checks your code
267against the gem5 style rules on %s.
268This script will now install the hook in your %s.
269Press enter to continue, or ctrl-c to abort: """
270
271mercurial_style_message = """
272You're missing the gem5 style hook, which automatically checks your code
273against the gem5 style rules on hg commit and qrefresh commands.
274This script will now install the hook in your .hg/hgrc file.
275Press enter to continue, or ctrl-c to abort: """
276
277git_style_message = """
278You're missing the gem5 style or commit message hook. These hooks help
279to ensure that your code follows gem5's style rules on git commit.
280This script will now install the hook in your .git/hooks/ directory.
281Press enter to continue, or ctrl-c to abort: """
282
283mercurial_style_upgrade_message = """
284Your Mercurial style hooks are not up-to-date. This script will now
285try to automatically update them. A backup of your hgrc will be saved
286in .hg/hgrc.old.
287Press enter to continue, or ctrl-c to abort: """
288
289mercurial_style_hook = """
290# The following lines were automatically added by gem5/SConstruct
291# to provide the gem5 style-checking hooks
292[extensions]
293hgstyle = %s/util/hgstyle.py
294
295[hooks]
296pretxncommit.style = python:hgstyle.check_style
297pre-qrefresh.style = python:hgstyle.check_style
298# End of SConstruct additions
299
300""" % (main.root.abspath)
301
302mercurial_lib_not_found = """
303Mercurial libraries cannot be found, ignoring style hook.  If
304you are a gem5 developer, please fix this and run the style
305hook. It is important.
306"""
307
308# Check for style hook and prompt for installation if it's not there.
309# Skip this if --ignore-style was specified, there's no interactive
310# terminal to prompt, or no recognized revision control system can be
311# found.
312ignore_style = GetOption('ignore_style') or not sys.stdin.isatty()
313
314# Try wire up Mercurial to the style hooks
315if not ignore_style and hgdir.exists():
316    style_hook = True
317    style_hooks = tuple()
318    hgrc = hgdir.File('hgrc')
319    hgrc_old = hgdir.File('hgrc.old')
320    try:
321        from mercurial import ui
322        ui = ui.ui()
323        ui.readconfig(hgrc.abspath)
324        style_hooks = (ui.config('hooks', 'pretxncommit.style', None),
325                       ui.config('hooks', 'pre-qrefresh.style', None))
326        style_hook = all(style_hooks)
327        style_extension = ui.config('extensions', 'style', None)
328    except ImportError:
329        print mercurial_lib_not_found
330
331    if "python:style.check_style" in style_hooks:
332        # Try to upgrade the style hooks
333        print mercurial_style_upgrade_message
334        # continue unless user does ctrl-c/ctrl-d etc.
335        try:
336            raw_input()
337        except:
338            print "Input exception, exiting scons.\n"
339            sys.exit(1)
340        shutil.copyfile(hgrc.abspath, hgrc_old.abspath)
341        re_style_hook = re.compile(r"^([^=#]+)\.style\s*=\s*([^#\s]+).*")
342        re_style_extension = re.compile("style\s*=\s*([^#\s]+).*")
343        old, new = open(hgrc_old.abspath, 'r'), open(hgrc.abspath, 'w')
344        for l in old:
345            m_hook = re_style_hook.match(l)
346            m_ext = re_style_extension.match(l)
347            if m_hook:
348                hook, check = m_hook.groups()
349                if check != "python:style.check_style":
350                    print "Warning: %s.style is using a non-default " \
351                        "checker: %s" % (hook, check)
352                if hook not in ("pretxncommit", "pre-qrefresh"):
353                    print "Warning: Updating unknown style hook: %s" % hook
354
355                l = "%s.style = python:hgstyle.check_style\n" % hook
356            elif m_ext and m_ext.group(1) == style_extension:
357                l = "hgstyle = %s/util/hgstyle.py\n" % main.root.abspath
358
359            new.write(l)
360    elif not style_hook:
361        print mercurial_style_message,
362        # continue unless user does ctrl-c/ctrl-d etc.
363        try:
364            raw_input()
365        except:
366            print "Input exception, exiting scons.\n"
367            sys.exit(1)
368        hgrc_path = '%s/.hg/hgrc' % main.root.abspath
369        print "Adding style hook to", hgrc_path, "\n"
370        try:
371            with open(hgrc_path, 'a') as f:
372                f.write(mercurial_style_hook)
373        except:
374            print "Error updating", hgrc_path
375            sys.exit(1)
376
377def install_git_style_hooks():
378    try:
379        gitdir = Dir(readCommand(
380            ["git", "rev-parse", "--git-dir"]).strip("\n"))
381    except Exception, e:
382        print "Warning: Failed to find git repo directory: %s" % e
383        return
384
385    git_hooks = gitdir.Dir("hooks")
386    def hook_exists(hook_name):
387        hook = git_hooks.File(hook_name)
388        return hook.exists()
389
390    def hook_install(hook_name, script):
391        hook = git_hooks.File(hook_name)
392        if hook.exists():
393            print "Warning: Can't install %s, hook already exists." % hook_name
394            return
395
396        if hook.islink():
397            print "Warning: Removing broken symlink for hook %s." % hook_name
398            os.unlink(hook.get_abspath())
399
400        if not git_hooks.exists():
401            mkdir(git_hooks.get_abspath())
402
403        abs_symlink_hooks = git_hooks.islink() and \
404            os.path.isabs(os.readlink(git_hooks.get_abspath()))
405
406        # Use a relative symlink if the hooks live in the source directory,
407        # and the hooks directory is not a symlink to an absolute path.
408        if hook.is_under(main.root) and not abs_symlink_hooks:
409            script_path = os.path.relpath(
410                script.get_abspath(),
411                hook.Dir(".").get_abspath())
412        else:
413            script_path = script.get_abspath()
414
415        try:
416            os.symlink(script_path, hook.get_abspath())
417        except:
418            print "Error updating git %s hook" % hook_name
419            raise
420
421    if hook_exists("pre-commit") and hook_exists("commit-msg"):
422        return
423
424    print git_style_message,
425    try:
426        raw_input()
427    except:
428        print "Input exception, exiting scons.\n"
429        sys.exit(1)
430
431    git_style_script = File("util/git-pre-commit.py")
432    git_msg_script = File("ext/git-commit-msg")
433
434    hook_install("pre-commit", git_style_script)
435    hook_install("commit-msg", git_msg_script)
436
437# Try to wire up git to the style hooks
438if not ignore_style and main.root.Entry(".git").exists():
439    install_git_style_hooks()
440
441###################################################
442#
443# Figure out which configurations to set up based on the path(s) of
444# the target(s).
445#
446###################################################
447
448# Find default configuration & binary.
449Default(environ.get('M5_DEFAULT_BINARY', 'build/ALPHA/gem5.debug'))
450
451# helper function: find last occurrence of element in list
452def rfind(l, elt, offs = -1):
453    for i in range(len(l)+offs, 0, -1):
454        if l[i] == elt:
455            return i
456    raise ValueError, "element not found"
457
458# Take a list of paths (or SCons Nodes) and return a list with all
459# paths made absolute and ~-expanded.  Paths will be interpreted
460# relative to the launch directory unless a different root is provided
461def makePathListAbsolute(path_list, root=GetLaunchDir()):
462    return [abspath(joinpath(root, expanduser(str(p))))
463            for p in path_list]
464
465# Each target must have 'build' in the interior of the path; the
466# directory below this will determine the build parameters.  For
467# example, for target 'foo/bar/build/ALPHA_SE/arch/alpha/blah.do' we
468# recognize that ALPHA_SE specifies the configuration because it
469# follow 'build' in the build path.
470
471# The funky assignment to "[:]" is needed to replace the list contents
472# in place rather than reassign the symbol to a new list, which
473# doesn't work (obviously!).
474BUILD_TARGETS[:] = makePathListAbsolute(BUILD_TARGETS)
475
476# Generate a list of the unique build roots and configs that the
477# collected targets reference.
478variant_paths = []
479build_root = None
480for t in BUILD_TARGETS:
481    path_dirs = t.split('/')
482    try:
483        build_top = rfind(path_dirs, 'build', -2)
484    except:
485        print "Error: no non-leaf 'build' dir found on target path", t
486        Exit(1)
487    this_build_root = joinpath('/',*path_dirs[:build_top+1])
488    if not build_root:
489        build_root = this_build_root
490    else:
491        if this_build_root != build_root:
492            print "Error: build targets not under same build root\n"\
493                  "  %s\n  %s" % (build_root, this_build_root)
494            Exit(1)
495    variant_path = joinpath('/',*path_dirs[:build_top+2])
496    if variant_path not in variant_paths:
497        variant_paths.append(variant_path)
498
499# Make sure build_root exists (might not if this is the first build there)
500if not isdir(build_root):
501    mkdir(build_root)
502main['BUILDROOT'] = build_root
503
504Export('main')
505
506main.SConsignFile(joinpath(build_root, "sconsign"))
507
508# Default duplicate option is to use hard links, but this messes up
509# when you use emacs to edit a file in the target dir, as emacs moves
510# file to file~ then copies to file, breaking the link.  Symbolic
511# (soft) links work better.
512main.SetOption('duplicate', 'soft-copy')
513
514#
515# Set up global sticky variables... these are common to an entire build
516# tree (not specific to a particular build like ALPHA_SE)
517#
518
519global_vars_file = joinpath(build_root, 'variables.global')
520
521global_vars = Variables(global_vars_file, args=ARGUMENTS)
522
523global_vars.AddVariables(
524    ('CC', 'C compiler', environ.get('CC', main['CC'])),
525    ('CXX', 'C++ compiler', environ.get('CXX', main['CXX'])),
526    ('SWIG', 'SWIG tool', environ.get('SWIG', main['SWIG'])),
527    ('PROTOC', 'protoc tool', environ.get('PROTOC', 'protoc')),
528    ('BATCH', 'Use batch pool for build and tests', False),
529    ('BATCH_CMD', 'Batch pool submission command name', 'qdo'),
530    ('M5_BUILD_CACHE', 'Cache built objects in this directory', False),
531    ('EXTRAS', 'Add extra directories to the compilation', '')
532    )
533
534# Update main environment with values from ARGUMENTS & global_vars_file
535global_vars.Update(main)
536help_texts["global_vars"] += global_vars.GenerateHelpText(main)
537
538# Save sticky variable settings back to current variables file
539global_vars.Save(global_vars_file, main)
540
541# Parse EXTRAS variable to build list of all directories where we're
542# look for sources etc.  This list is exported as extras_dir_list.
543base_dir = main.srcdir.abspath
544if main['EXTRAS']:
545    extras_dir_list = makePathListAbsolute(main['EXTRAS'].split(':'))
546else:
547    extras_dir_list = []
548
549Export('base_dir')
550Export('extras_dir_list')
551
552# the ext directory should be on the #includes path
553main.Append(CPPPATH=[Dir('ext')])
554
555def strip_build_path(path, env):
556    path = str(path)
557    variant_base = env['BUILDROOT'] + os.path.sep
558    if path.startswith(variant_base):
559        path = path[len(variant_base):]
560    elif path.startswith('build/'):
561        path = path[6:]
562    return path
563
564# Generate a string of the form:
565#   common/path/prefix/src1, src2 -> tgt1, tgt2
566# to print while building.
567class Transform(object):
568    # all specific color settings should be here and nowhere else
569    tool_color = termcap.Normal
570    pfx_color = termcap.Yellow
571    srcs_color = termcap.Yellow + termcap.Bold
572    arrow_color = termcap.Blue + termcap.Bold
573    tgts_color = termcap.Yellow + termcap.Bold
574
575    def __init__(self, tool, max_sources=99):
576        self.format = self.tool_color + (" [%8s] " % tool) \
577                      + self.pfx_color + "%s" \
578                      + self.srcs_color + "%s" \
579                      + self.arrow_color + " -> " \
580                      + self.tgts_color + "%s" \
581                      + termcap.Normal
582        self.max_sources = max_sources
583
584    def __call__(self, target, source, env, for_signature=None):
585        # truncate source list according to max_sources param
586        source = source[0:self.max_sources]
587        def strip(f):
588            return strip_build_path(str(f), env)
589        if len(source) > 0:
590            srcs = map(strip, source)
591        else:
592            srcs = ['']
593        tgts = map(strip, target)
594        # surprisingly, os.path.commonprefix is a dumb char-by-char string
595        # operation that has nothing to do with paths.
596        com_pfx = os.path.commonprefix(srcs + tgts)
597        com_pfx_len = len(com_pfx)
598        if com_pfx:
599            # do some cleanup and sanity checking on common prefix
600            if com_pfx[-1] == ".":
601                # prefix matches all but file extension: ok
602                # back up one to change 'foo.cc -> o' to 'foo.cc -> .o'
603                com_pfx = com_pfx[0:-1]
604            elif com_pfx[-1] == "/":
605                # common prefix is directory path: OK
606                pass
607            else:
608                src0_len = len(srcs[0])
609                tgt0_len = len(tgts[0])
610                if src0_len == com_pfx_len:
611                    # source is a substring of target, OK
612                    pass
613                elif tgt0_len == com_pfx_len:
614                    # target is a substring of source, need to back up to
615                    # avoid empty string on RHS of arrow
616                    sep_idx = com_pfx.rfind(".")
617                    if sep_idx != -1:
618                        com_pfx = com_pfx[0:sep_idx]
619                    else:
620                        com_pfx = ''
621                elif src0_len > com_pfx_len and srcs[0][com_pfx_len] == ".":
622                    # still splitting at file extension: ok
623                    pass
624                else:
625                    # probably a fluke; ignore it
626                    com_pfx = ''
627        # recalculate length in case com_pfx was modified
628        com_pfx_len = len(com_pfx)
629        def fmt(files):
630            f = map(lambda s: s[com_pfx_len:], files)
631            return ', '.join(f)
632        return self.format % (com_pfx, fmt(srcs), fmt(tgts))
633
634Export('Transform')
635
636# enable the regression script to use the termcap
637main['TERMCAP'] = termcap
638
639if GetOption('verbose'):
640    def MakeAction(action, string, *args, **kwargs):
641        return Action(action, *args, **kwargs)
642else:
643    MakeAction = Action
644    main['CCCOMSTR']        = Transform("CC")
645    main['CXXCOMSTR']       = Transform("CXX")
646    main['ASCOMSTR']        = Transform("AS")
647    main['SWIGCOMSTR']      = Transform("SWIG")
648    main['ARCOMSTR']        = Transform("AR", 0)
649    main['LINKCOMSTR']      = Transform("LINK", 0)
650    main['RANLIBCOMSTR']    = Transform("RANLIB", 0)
651    main['M4COMSTR']        = Transform("M4")
652    main['SHCCCOMSTR']      = Transform("SHCC")
653    main['SHCXXCOMSTR']     = Transform("SHCXX")
654Export('MakeAction')
655
656# Initialize the Link-Time Optimization (LTO) flags
657main['LTO_CCFLAGS'] = []
658main['LTO_LDFLAGS'] = []
659
660# According to the readme, tcmalloc works best if the compiler doesn't
661# assume that we're using the builtin malloc and friends. These flags
662# are compiler-specific, so we need to set them after we detect which
663# compiler we're using.
664main['TCMALLOC_CCFLAGS'] = []
665
666CXX_version = readCommand([main['CXX'],'--version'], exception=False)
667CXX_V = readCommand([main['CXX'],'-V'], exception=False)
668
669main['GCC'] = CXX_version and CXX_version.find('g++') >= 0
670main['CLANG'] = CXX_version and CXX_version.find('clang') >= 0
671if main['GCC'] + main['CLANG'] > 1:
672    print 'Error: How can we have two at the same time?'
673    Exit(1)
674
675# Set up default C++ compiler flags
676if main['GCC'] or main['CLANG']:
677    # As gcc and clang share many flags, do the common parts here
678    main.Append(CCFLAGS=['-pipe'])
679    main.Append(CCFLAGS=['-fno-strict-aliasing'])
680    # Enable -Wall and -Wextra and then disable the few warnings that
681    # we consistently violate
682    main.Append(CCFLAGS=['-Wall', '-Wundef', '-Wextra',
683                         '-Wno-sign-compare', '-Wno-unused-parameter'])
684    # We always compile using C++11
685    main.Append(CXXFLAGS=['-std=c++11'])
686    if sys.platform.startswith('freebsd'):
687        main.Append(CCFLAGS=['-I/usr/local/include'])
688        main.Append(CXXFLAGS=['-I/usr/local/include'])
689else:
690    print termcap.Yellow + termcap.Bold + 'Error' + termcap.Normal,
691    print "Don't know what compiler options to use for your compiler."
692    print termcap.Yellow + '       compiler:' + termcap.Normal, main['CXX']
693    print termcap.Yellow + '       version:' + termcap.Normal,
694    if not CXX_version:
695        print termcap.Yellow + termcap.Bold + "COMMAND NOT FOUND!" +\
696               termcap.Normal
697    else:
698        print CXX_version.replace('\n', '<nl>')
699    print "       If you're trying to use a compiler other than GCC"
700    print "       or clang, there appears to be something wrong with your"
701    print "       environment."
702    print "       "
703    print "       If you are trying to use a compiler other than those listed"
704    print "       above you will need to ease fix SConstruct and "
705    print "       src/SConscript to support that compiler."
706    Exit(1)
707
708if main['GCC']:
709    # Check for a supported version of gcc. >= 4.8 is chosen for its
710    # level of c++11 support. See
711    # http://gcc.gnu.org/projects/cxx0x.html for details.
712    gcc_version = readCommand([main['CXX'], '-dumpversion'], exception=False)
713    if compareVersions(gcc_version, "4.8") < 0:
714        print 'Error: gcc version 4.8 or newer required.'
715        print '       Installed version:', gcc_version
716        Exit(1)
717
718    main['GCC_VERSION'] = gcc_version
719
720    # gcc from version 4.8 and above generates "rep; ret" instructions
721    # to avoid performance penalties on certain AMD chips. Older
722    # assemblers detect this as an error, "Error: expecting string
723    # instruction after `rep'"
724    as_version_raw = readCommand([main['AS'], '-v', '/dev/null',
725                                  '-o', '/dev/null'],
726                                 exception=False).split()
727
728    # version strings may contain extra distro-specific
729    # qualifiers, so play it safe and keep only what comes before
730    # the first hyphen
731    as_version = as_version_raw[-1].split('-')[0] if as_version_raw else None
732
733    if not as_version or compareVersions(as_version, "2.23") < 0:
734        print termcap.Yellow + termcap.Bold + \
735            'Warning: This combination of gcc and binutils have' + \
736            ' known incompatibilities.\n' + \
737            '         If you encounter build problems, please update ' + \
738            'binutils to 2.23.' + \
739            termcap.Normal
740
741    # Make sure we warn if the user has requested to compile with the
742    # Undefined Benahvior Sanitizer and this version of gcc does not
743    # support it.
744    if GetOption('with_ubsan') and \
745            compareVersions(gcc_version, '4.9') < 0:
746        print termcap.Yellow + termcap.Bold + \
747            'Warning: UBSan is only supported using gcc 4.9 and later.' + \
748            termcap.Normal
749
750    # Add the appropriate Link-Time Optimization (LTO) flags
751    # unless LTO is explicitly turned off. Note that these flags
752    # are only used by the fast target.
753    if not GetOption('no_lto'):
754        # Pass the LTO flag when compiling to produce GIMPLE
755        # output, we merely create the flags here and only append
756        # them later
757        main['LTO_CCFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
758
759        # Use the same amount of jobs for LTO as we are running
760        # scons with
761        main['LTO_LDFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
762
763    main.Append(TCMALLOC_CCFLAGS=['-fno-builtin-malloc', '-fno-builtin-calloc',
764                                  '-fno-builtin-realloc', '-fno-builtin-free'])
765
766    # add option to check for undeclared overrides
767    if compareVersions(gcc_version, "5.0") > 0:
768        main.Append(CCFLAGS=['-Wno-error=suggest-override'])
769
770elif main['CLANG']:
771    # Check for a supported version of clang, >= 3.1 is needed to
772    # support similar features as gcc 4.8. See
773    # http://clang.llvm.org/cxx_status.html for details
774    clang_version_re = re.compile(".* version (\d+\.\d+)")
775    clang_version_match = clang_version_re.search(CXX_version)
776    if (clang_version_match):
777        clang_version = clang_version_match.groups()[0]
778        if compareVersions(clang_version, "3.1") < 0:
779            print 'Error: clang version 3.1 or newer required.'
780            print '       Installed version:', clang_version
781            Exit(1)
782    else:
783        print 'Error: Unable to determine clang version.'
784        Exit(1)
785
786    # clang has a few additional warnings that we disable, extraneous
787    # parantheses are allowed due to Ruby's printing of the AST,
788    # finally self assignments are allowed as the generated CPU code
789    # is relying on this
790    main.Append(CCFLAGS=['-Wno-parentheses',
791                         '-Wno-self-assign',
792                         # Some versions of libstdc++ (4.8?) seem to
793                         # use struct hash and class hash
794                         # interchangeably.
795                         '-Wno-mismatched-tags',
796                         ])
797
798    main.Append(TCMALLOC_CCFLAGS=['-fno-builtin'])
799
800    # On Mac OS X/Darwin we need to also use libc++ (part of XCode) as
801    # opposed to libstdc++, as the later is dated.
802    if sys.platform == "darwin":
803        main.Append(CXXFLAGS=['-stdlib=libc++'])
804        main.Append(LIBS=['c++'])
805
806    # On FreeBSD we need libthr.
807    if sys.platform.startswith('freebsd'):
808        main.Append(LIBS=['thr'])
809
810else:
811    print termcap.Yellow + termcap.Bold + 'Error' + termcap.Normal,
812    print "Don't know what compiler options to use for your compiler."
813    print termcap.Yellow + '       compiler:' + termcap.Normal, main['CXX']
814    print termcap.Yellow + '       version:' + termcap.Normal,
815    if not CXX_version:
816        print termcap.Yellow + termcap.Bold + "COMMAND NOT FOUND!" +\
817               termcap.Normal
818    else:
819        print CXX_version.replace('\n', '<nl>')
820    print "       If you're trying to use a compiler other than GCC"
821    print "       or clang, there appears to be something wrong with your"
822    print "       environment."
823    print "       "
824    print "       If you are trying to use a compiler other than those listed"
825    print "       above you will need to ease fix SConstruct and "
826    print "       src/SConscript to support that compiler."
827    Exit(1)
828
829# Set up common yacc/bison flags (needed for Ruby)
830main['YACCFLAGS'] = '-d'
831main['YACCHXXFILESUFFIX'] = '.hh'
832
833# Do this after we save setting back, or else we'll tack on an
834# extra 'qdo' every time we run scons.
835if main['BATCH']:
836    main['CC']     = main['BATCH_CMD'] + ' ' + main['CC']
837    main['CXX']    = main['BATCH_CMD'] + ' ' + main['CXX']
838    main['AS']     = main['BATCH_CMD'] + ' ' + main['AS']
839    main['AR']     = main['BATCH_CMD'] + ' ' + main['AR']
840    main['RANLIB'] = main['BATCH_CMD'] + ' ' + main['RANLIB']
841
842if sys.platform == 'cygwin':
843    # cygwin has some header file issues...
844    main.Append(CCFLAGS=["-Wno-uninitialized"])
845
846# Check for the protobuf compiler
847protoc_version = readCommand([main['PROTOC'], '--version'],
848                             exception='').split()
849
850# First two words should be "libprotoc x.y.z"
851if len(protoc_version) < 2 or protoc_version[0] != 'libprotoc':
852    print termcap.Yellow + termcap.Bold + \
853        'Warning: Protocol buffer compiler (protoc) not found.\n' + \
854        '         Please install protobuf-compiler for tracing support.' + \
855        termcap.Normal
856    main['PROTOC'] = False
857else:
858    # Based on the availability of the compress stream wrappers,
859    # require 2.1.0
860    min_protoc_version = '2.1.0'
861    if compareVersions(protoc_version[1], min_protoc_version) < 0:
862        print termcap.Yellow + termcap.Bold + \
863            'Warning: protoc version', min_protoc_version, \
864            'or newer required.\n' + \
865            '         Installed version:', protoc_version[1], \
866            termcap.Normal
867        main['PROTOC'] = False
868    else:
869        # Attempt to determine the appropriate include path and
870        # library path using pkg-config, that means we also need to
871        # check for pkg-config. Note that it is possible to use
872        # protobuf without the involvement of pkg-config. Later on we
873        # check go a library config check and at that point the test
874        # will fail if libprotobuf cannot be found.
875        if readCommand(['pkg-config', '--version'], exception=''):
876            try:
877                # Attempt to establish what linking flags to add for protobuf
878                # using pkg-config
879                main.ParseConfig('pkg-config --cflags --libs-only-L protobuf')
880            except:
881                print termcap.Yellow + termcap.Bold + \
882                    'Warning: pkg-config could not get protobuf flags.' + \
883                    termcap.Normal
884
885# Check for SWIG
886if not main.has_key('SWIG'):
887    print 'Error: SWIG utility not found.'
888    print '       Please install (see http://www.swig.org) and retry.'
889    Exit(1)
890
891# Check for appropriate SWIG version
892swig_version = readCommand([main['SWIG'], '-version'], exception='').split()
893# First 3 words should be "SWIG Version x.y.z"
894if len(swig_version) < 3 or \
895        swig_version[0] != 'SWIG' or swig_version[1] != 'Version':
896    print 'Error determining SWIG version.'
897    Exit(1)
898
899min_swig_version = '2.0.4'
900if compareVersions(swig_version[2], min_swig_version) < 0:
901    print 'Error: SWIG version', min_swig_version, 'or newer required.'
902    print '       Installed version:', swig_version[2]
903    Exit(1)
904
905# Check for known incompatibilities. The standard library shipped with
906# gcc >= 4.9 does not play well with swig versions prior to 3.0
907if main['GCC'] and compareVersions(gcc_version, '4.9') >= 0 and \
908        compareVersions(swig_version[2], '3.0') < 0:
909    print termcap.Yellow + termcap.Bold + \
910        'Warning: This combination of gcc and swig have' + \
911        ' known incompatibilities.\n' + \
912        '         If you encounter build problems, please update ' + \
913        'swig to 3.0 or later.' + \
914        termcap.Normal
915
916# Set up SWIG flags & scanner
917swig_flags=Split('-c++ -python -modern -templatereduce $_CPPINCFLAGS')
918main.Append(SWIGFLAGS=swig_flags)
919
920# Check for 'timeout' from GNU coreutils. If present, regressions will
921# be run with a time limit. We require version 8.13 since we rely on
922# support for the '--foreground' option.
923if sys.platform.startswith('freebsd'):
924    timeout_lines = readCommand(['gtimeout', '--version'],
925                                exception='').splitlines()
926else:
927    timeout_lines = readCommand(['timeout', '--version'],
928                                exception='').splitlines()
929# Get the first line and tokenize it
930timeout_version = timeout_lines[0].split() if timeout_lines else []
931main['TIMEOUT'] =  timeout_version and \
932    compareVersions(timeout_version[-1], '8.13') >= 0
933
934# filter out all existing swig scanners, they mess up the dependency
935# stuff for some reason
936scanners = []
937for scanner in main['SCANNERS']:
938    skeys = scanner.skeys
939    if skeys == '.i':
940        continue
941
942    if isinstance(skeys, (list, tuple)) and '.i' in skeys:
943        continue
944
945    scanners.append(scanner)
946
947# add the new swig scanner that we like better
948from SCons.Scanner import ClassicCPP as CPPScanner
949swig_inc_re = '^[ \t]*[%,#][ \t]*(?:include|import)[ \t]*(<|")([^>"]+)(>|")'
950scanners.append(CPPScanner("SwigScan", [ ".i" ], "CPPPATH", swig_inc_re))
951
952# replace the scanners list that has what we want
953main['SCANNERS'] = scanners
954
955# Add a custom Check function to test for structure members.
956def CheckMember(context, include, decl, member, include_quotes="<>"):
957    context.Message("Checking for member %s in %s..." %
958                    (member, decl))
959    text = """
960#include %(header)s
961int main(){
962  %(decl)s test;
963  (void)test.%(member)s;
964  return 0;
965};
966""" % { "header" : include_quotes[0] + include + include_quotes[1],
967        "decl" : decl,
968        "member" : member,
969        }
970
971    ret = context.TryCompile(text, extension=".cc")
972    context.Result(ret)
973    return ret
974
975# Platform-specific configuration.  Note again that we assume that all
976# builds under a given build root run on the same host platform.
977conf = Configure(main,
978                 conf_dir = joinpath(build_root, '.scons_config'),
979                 log_file = joinpath(build_root, 'scons_config.log'),
980                 custom_tests = {
981        'CheckMember' : CheckMember,
982        })
983
984# Check if we should compile a 64 bit binary on Mac OS X/Darwin
985try:
986    import platform
987    uname = platform.uname()
988    if uname[0] == 'Darwin' and compareVersions(uname[2], '9.0.0') >= 0:
989        if int(readCommand('sysctl -n hw.cpu64bit_capable')[0]):
990            main.Append(CCFLAGS=['-arch', 'x86_64'])
991            main.Append(CFLAGS=['-arch', 'x86_64'])
992            main.Append(LINKFLAGS=['-arch', 'x86_64'])
993            main.Append(ASFLAGS=['-arch', 'x86_64'])
994except:
995    pass
996
997# Recent versions of scons substitute a "Null" object for Configure()
998# when configuration isn't necessary, e.g., if the "--help" option is
999# present.  Unfortuantely this Null object always returns false,
1000# breaking all our configuration checks.  We replace it with our own
1001# more optimistic null object that returns True instead.
1002if not conf:
1003    def NullCheck(*args, **kwargs):
1004        return True
1005
1006    class NullConf:
1007        def __init__(self, env):
1008            self.env = env
1009        def Finish(self):
1010            return self.env
1011        def __getattr__(self, mname):
1012            return NullCheck
1013
1014    conf = NullConf(main)
1015
1016# Cache build files in the supplied directory.
1017if main['M5_BUILD_CACHE']:
1018    print 'Using build cache located at', main['M5_BUILD_CACHE']
1019    CacheDir(main['M5_BUILD_CACHE'])
1020
1021if not GetOption('without_python'):
1022    # Find Python include and library directories for embedding the
1023    # interpreter. We rely on python-config to resolve the appropriate
1024    # includes and linker flags. ParseConfig does not seem to understand
1025    # the more exotic linker flags such as -Xlinker and -export-dynamic so
1026    # we add them explicitly below. If you want to link in an alternate
1027    # version of python, see above for instructions on how to invoke
1028    # scons with the appropriate PATH set.
1029    #
1030    # First we check if python2-config exists, else we use python-config
1031    python_config = readCommand(['which', 'python2-config'],
1032                                exception='').strip()
1033    if not os.path.exists(python_config):
1034        python_config = readCommand(['which', 'python-config'],
1035                                    exception='').strip()
1036    py_includes = readCommand([python_config, '--includes'],
1037                              exception='').split()
1038    # Strip the -I from the include folders before adding them to the
1039    # CPPPATH
1040    main.Append(CPPPATH=map(lambda inc: inc[2:], py_includes))
1041
1042    # Read the linker flags and split them into libraries and other link
1043    # flags. The libraries are added later through the call the CheckLib.
1044    py_ld_flags = readCommand([python_config, '--ldflags'],
1045        exception='').split()
1046    py_libs = []
1047    for lib in py_ld_flags:
1048         if not lib.startswith('-l'):
1049             main.Append(LINKFLAGS=[lib])
1050         else:
1051             lib = lib[2:]
1052             if lib not in py_libs:
1053                 py_libs.append(lib)
1054
1055    # verify that this stuff works
1056    if not conf.CheckHeader('Python.h', '<>'):
1057        print "Error: can't find Python.h header in", py_includes
1058        print "Install Python headers (package python-dev on Ubuntu and RedHat)"
1059        Exit(1)
1060
1061    for lib in py_libs:
1062        if not conf.CheckLib(lib):
1063            print "Error: can't find library %s required by python" % lib
1064            Exit(1)
1065
1066# On Solaris you need to use libsocket for socket ops
1067if not conf.CheckLibWithHeader(None, 'sys/socket.h', 'C++', 'accept(0,0,0);'):
1068   if not conf.CheckLibWithHeader('socket', 'sys/socket.h', 'C++', 'accept(0,0,0);'):
1069       print "Can't find library with socket calls (e.g. accept())"
1070       Exit(1)
1071
1072# Check for zlib.  If the check passes, libz will be automatically
1073# added to the LIBS environment variable.
1074if not conf.CheckLibWithHeader('z', 'zlib.h', 'C++','zlibVersion();'):
1075    print 'Error: did not find needed zlib compression library '\
1076          'and/or zlib.h header file.'
1077    print '       Please install zlib and try again.'
1078    Exit(1)
1079
1080# If we have the protobuf compiler, also make sure we have the
1081# development libraries. If the check passes, libprotobuf will be
1082# automatically added to the LIBS environment variable. After
1083# this, we can use the HAVE_PROTOBUF flag to determine if we have
1084# got both protoc and libprotobuf available.
1085main['HAVE_PROTOBUF'] = main['PROTOC'] and \
1086    conf.CheckLibWithHeader('protobuf', 'google/protobuf/message.h',
1087                            'C++', 'GOOGLE_PROTOBUF_VERIFY_VERSION;')
1088
1089# If we have the compiler but not the library, print another warning.
1090if main['PROTOC'] and not main['HAVE_PROTOBUF']:
1091    print termcap.Yellow + termcap.Bold + \
1092        'Warning: did not find protocol buffer library and/or headers.\n' + \
1093    '       Please install libprotobuf-dev for tracing support.' + \
1094    termcap.Normal
1095
1096# Check for librt.
1097have_posix_clock = \
1098    conf.CheckLibWithHeader(None, 'time.h', 'C',
1099                            'clock_nanosleep(0,0,NULL,NULL);') or \
1100    conf.CheckLibWithHeader('rt', 'time.h', 'C',
1101                            'clock_nanosleep(0,0,NULL,NULL);')
1102
1103have_posix_timers = \
1104    conf.CheckLibWithHeader([None, 'rt'], [ 'time.h', 'signal.h' ], 'C',
1105                            'timer_create(CLOCK_MONOTONIC, NULL, NULL);')
1106
1107if not GetOption('without_tcmalloc'):
1108    if conf.CheckLib('tcmalloc'):
1109        main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
1110    elif conf.CheckLib('tcmalloc_minimal'):
1111        main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
1112    else:
1113        print termcap.Yellow + termcap.Bold + \
1114              "You can get a 12% performance improvement by "\
1115              "installing tcmalloc (libgoogle-perftools-dev package "\
1116              "on Ubuntu or RedHat)." + termcap.Normal
1117
1118
1119# Detect back trace implementations. The last implementation in the
1120# list will be used by default.
1121backtrace_impls = [ "none" ]
1122
1123if conf.CheckLibWithHeader(None, 'execinfo.h', 'C',
1124                           'backtrace_symbols_fd((void*)0, 0, 0);'):
1125    backtrace_impls.append("glibc")
1126elif conf.CheckLibWithHeader('execinfo', 'execinfo.h', 'C',
1127                           'backtrace_symbols_fd((void*)0, 0, 0);'):
1128    # NetBSD and FreeBSD need libexecinfo.
1129    backtrace_impls.append("glibc")
1130    main.Append(LIBS=['execinfo'])
1131
1132if backtrace_impls[-1] == "none":
1133    default_backtrace_impl = "none"
1134    print termcap.Yellow + termcap.Bold + \
1135        "No suitable back trace implementation found." + \
1136        termcap.Normal
1137
1138if not have_posix_clock:
1139    print "Can't find library for POSIX clocks."
1140
1141# Check for <fenv.h> (C99 FP environment control)
1142have_fenv = conf.CheckHeader('fenv.h', '<>')
1143if not have_fenv:
1144    print "Warning: Header file <fenv.h> not found."
1145    print "         This host has no IEEE FP rounding mode control."
1146
1147# Check if we should enable KVM-based hardware virtualization. The API
1148# we rely on exists since version 2.6.36 of the kernel, but somehow
1149# the KVM_API_VERSION does not reflect the change. We test for one of
1150# the types as a fall back.
1151have_kvm = conf.CheckHeader('linux/kvm.h', '<>')
1152if not have_kvm:
1153    print "Info: Compatible header file <linux/kvm.h> not found, " \
1154        "disabling KVM support."
1155
1156# x86 needs support for xsave. We test for the structure here since we
1157# won't be able to run new tests by the time we know which ISA we're
1158# targeting.
1159have_kvm_xsave = conf.CheckTypeSize('struct kvm_xsave',
1160                                    '#include <linux/kvm.h>') != 0
1161
1162# Check if the requested target ISA is compatible with the host
1163def is_isa_kvm_compatible(isa):
1164    try:
1165        import platform
1166        host_isa = platform.machine()
1167    except:
1168        print "Warning: Failed to determine host ISA."
1169        return False
1170
1171    if not have_posix_timers:
1172        print "Warning: Can not enable KVM, host seems to lack support " \
1173            "for POSIX timers"
1174        return False
1175
1176    if isa == "arm":
1177        return host_isa in ( "armv7l", "aarch64" )
1178    elif isa == "x86":
1179        if host_isa != "x86_64":
1180            return False
1181
1182        if not have_kvm_xsave:
1183            print "KVM on x86 requires xsave support in kernel headers."
1184            return False
1185
1186        return True
1187    else:
1188        return False
1189
1190
1191# Check if the exclude_host attribute is available. We want this to
1192# get accurate instruction counts in KVM.
1193main['HAVE_PERF_ATTR_EXCLUDE_HOST'] = conf.CheckMember(
1194    'linux/perf_event.h', 'struct perf_event_attr', 'exclude_host')
1195
1196
1197######################################################################
1198#
1199# Finish the configuration
1200#
1201main = conf.Finish()
1202
1203######################################################################
1204#
1205# Collect all non-global variables
1206#
1207
1208# Define the universe of supported ISAs
1209all_isa_list = [ ]
1210all_gpu_isa_list = [ ]
1211Export('all_isa_list')
1212Export('all_gpu_isa_list')
1213
1214class CpuModel(object):
1215    '''The CpuModel class encapsulates everything the ISA parser needs to
1216    know about a particular CPU model.'''
1217
1218    # Dict of available CPU model objects.  Accessible as CpuModel.dict.
1219    dict = {}
1220
1221    # Constructor.  Automatically adds models to CpuModel.dict.
1222    def __init__(self, name, default=False):
1223        self.name = name           # name of model
1224
1225        # This cpu is enabled by default
1226        self.default = default
1227
1228        # Add self to dict
1229        if name in CpuModel.dict:
1230            raise AttributeError, "CpuModel '%s' already registered" % name
1231        CpuModel.dict[name] = self
1232
1233Export('CpuModel')
1234
1235# Sticky variables get saved in the variables file so they persist from
1236# one invocation to the next (unless overridden, in which case the new
1237# value becomes sticky).
1238sticky_vars = Variables(args=ARGUMENTS)
1239Export('sticky_vars')
1240
1241# Sticky variables that should be exported
1242export_vars = []
1243Export('export_vars')
1244
1245# For Ruby
1246all_protocols = []
1247Export('all_protocols')
1248protocol_dirs = []
1249Export('protocol_dirs')
1250slicc_includes = []
1251Export('slicc_includes')
1252
1253# Walk the tree and execute all SConsopts scripts that wil add to the
1254# above variables
1255if GetOption('verbose'):
1256    print "Reading SConsopts"
1257for bdir in [ base_dir ] + extras_dir_list:
1258    if not isdir(bdir):
1259        print "Error: directory '%s' does not exist" % bdir
1260        Exit(1)
1261    for root, dirs, files in os.walk(bdir):
1262        if 'SConsopts' in files:
1263            if GetOption('verbose'):
1264                print "Reading", joinpath(root, 'SConsopts')
1265            SConscript(joinpath(root, 'SConsopts'))
1266
1267all_isa_list.sort()
1268all_gpu_isa_list.sort()
1269
1270sticky_vars.AddVariables(
1271    EnumVariable('TARGET_ISA', 'Target ISA', 'alpha', all_isa_list),
1272    EnumVariable('TARGET_GPU_ISA', 'Target GPU ISA', 'hsail', all_gpu_isa_list),
1273    ListVariable('CPU_MODELS', 'CPU models',
1274                 sorted(n for n,m in CpuModel.dict.iteritems() if m.default),
1275                 sorted(CpuModel.dict.keys())),
1276    BoolVariable('EFENCE', 'Link with Electric Fence malloc debugger',
1277                 False),
1278    BoolVariable('SS_COMPATIBLE_FP',
1279                 'Make floating-point results compatible with SimpleScalar',
1280                 False),
1281    BoolVariable('USE_SSE2',
1282                 'Compile for SSE2 (-msse2) to get IEEE FP on x86 hosts',
1283                 False),
1284    BoolVariable('USE_POSIX_CLOCK', 'Use POSIX Clocks', have_posix_clock),
1285    BoolVariable('USE_FENV', 'Use <fenv.h> IEEE mode control', have_fenv),
1286    BoolVariable('CP_ANNOTATE', 'Enable critical path annotation capability', False),
1287    BoolVariable('USE_KVM', 'Enable hardware virtualized (KVM) CPU models', have_kvm),
1288    BoolVariable('BUILD_GPU', 'Build the compute-GPU model', False),
1289    EnumVariable('PROTOCOL', 'Coherence protocol for Ruby', 'None',
1290                  all_protocols),
1291    EnumVariable('BACKTRACE_IMPL', 'Post-mortem dump implementation',
1292                 backtrace_impls[-1], backtrace_impls)
1293    )
1294
1295# These variables get exported to #defines in config/*.hh (see src/SConscript).
1296export_vars += ['USE_FENV', 'SS_COMPATIBLE_FP', 'TARGET_ISA', 'TARGET_GPU_ISA',
1297                'CP_ANNOTATE', 'USE_POSIX_CLOCK', 'USE_KVM', 'PROTOCOL',
1298                'HAVE_PROTOBUF', 'HAVE_PERF_ATTR_EXCLUDE_HOST']
1299
1300###################################################
1301#
1302# Define a SCons builder for configuration flag headers.
1303#
1304###################################################
1305
1306# This function generates a config header file that #defines the
1307# variable symbol to the current variable setting (0 or 1).  The source
1308# operands are the name of the variable and a Value node containing the
1309# value of the variable.
1310def build_config_file(target, source, env):
1311    (variable, value) = [s.get_contents() for s in source]
1312    f = file(str(target[0]), 'w')
1313    print >> f, '#define', variable, value
1314    f.close()
1315    return None
1316
1317# Combine the two functions into a scons Action object.
1318config_action = MakeAction(build_config_file, Transform("CONFIG H", 2))
1319
1320# The emitter munges the source & target node lists to reflect what
1321# we're really doing.
1322def config_emitter(target, source, env):
1323    # extract variable name from Builder arg
1324    variable = str(target[0])
1325    # True target is config header file
1326    target = joinpath('config', variable.lower() + '.hh')
1327    val = env[variable]
1328    if isinstance(val, bool):
1329        # Force value to 0/1
1330        val = int(val)
1331    elif isinstance(val, str):
1332        val = '"' + val + '"'
1333
1334    # Sources are variable name & value (packaged in SCons Value nodes)
1335    return ([target], [Value(variable), Value(val)])
1336
1337config_builder = Builder(emitter = config_emitter, action = config_action)
1338
1339main.Append(BUILDERS = { 'ConfigFile' : config_builder })
1340
1341# libelf build is shared across all configs in the build root.
1342main.SConscript('ext/libelf/SConscript',
1343                variant_dir = joinpath(build_root, 'libelf'))
1344
1345# iostream3 build is shared across all configs in the build root.
1346main.SConscript('ext/iostream3/SConscript',
1347                variant_dir = joinpath(build_root, 'iostream3'))
1348
1349# libfdt build is shared across all configs in the build root.
1350main.SConscript('ext/libfdt/SConscript',
1351                variant_dir = joinpath(build_root, 'libfdt'))
1352
1353# fputils build is shared across all configs in the build root.
1354main.SConscript('ext/fputils/SConscript',
1355                variant_dir = joinpath(build_root, 'fputils'))
1356
1357# DRAMSim2 build is shared across all configs in the build root.
1358main.SConscript('ext/dramsim2/SConscript',
1359                variant_dir = joinpath(build_root, 'dramsim2'))
1360
1361# DRAMPower build is shared across all configs in the build root.
1362main.SConscript('ext/drampower/SConscript',
1363                variant_dir = joinpath(build_root, 'drampower'))
1364
1365# nomali build is shared across all configs in the build root.
1366main.SConscript('ext/nomali/SConscript',
1367                variant_dir = joinpath(build_root, 'nomali'))
1368
1369###################################################
1370#
1371# This function is used to set up a directory with switching headers
1372#
1373###################################################
1374
1375main['ALL_ISA_LIST'] = all_isa_list
1376main['ALL_GPU_ISA_LIST'] = all_gpu_isa_list
1377all_isa_deps = {}
1378def make_switching_dir(dname, switch_headers, env):
1379    # Generate the header.  target[0] is the full path of the output
1380    # header to generate.  'source' is a dummy variable, since we get the
1381    # list of ISAs from env['ALL_ISA_LIST'].
1382    def gen_switch_hdr(target, source, env):
1383        fname = str(target[0])
1384        isa = env['TARGET_ISA'].lower()
1385        try:
1386            f = open(fname, 'w')
1387            print >>f, '#include "%s/%s/%s"' % (dname, isa, basename(fname))
1388            f.close()
1389        except IOError:
1390            print "Failed to create %s" % fname
1391            raise
1392
1393    # Build SCons Action object. 'varlist' specifies env vars that this
1394    # action depends on; when env['ALL_ISA_LIST'] changes these actions
1395    # should get re-executed.
1396    switch_hdr_action = MakeAction(gen_switch_hdr,
1397                          Transform("GENERATE"), varlist=['ALL_ISA_LIST'])
1398
1399    # Instantiate actions for each header
1400    for hdr in switch_headers:
1401        env.Command(hdr, [], switch_hdr_action)
1402
1403    isa_target = Dir('.').up().name.lower().replace('_', '-')
1404    env['PHONY_BASE'] = '#'+isa_target
1405    all_isa_deps[isa_target] = None
1406
1407Export('make_switching_dir')
1408
1409def make_gpu_switching_dir(dname, switch_headers, env):
1410    # Generate the header.  target[0] is the full path of the output
1411    # header to generate.  'source' is a dummy variable, since we get the
1412    # list of ISAs from env['ALL_ISA_LIST'].
1413    def gen_switch_hdr(target, source, env):
1414        fname = str(target[0])
1415
1416        isa = env['TARGET_GPU_ISA'].lower()
1417
1418        try:
1419            f = open(fname, 'w')
1420            print >>f, '#include "%s/%s/%s"' % (dname, isa, basename(fname))
1421            f.close()
1422        except IOError:
1423            print "Failed to create %s" % fname
1424            raise
1425
1426    # Build SCons Action object. 'varlist' specifies env vars that this
1427    # action depends on; when env['ALL_ISA_LIST'] changes these actions
1428    # should get re-executed.
1429    switch_hdr_action = MakeAction(gen_switch_hdr,
1430                          Transform("GENERATE"), varlist=['ALL_ISA_GPU_LIST'])
1431
1432    # Instantiate actions for each header
1433    for hdr in switch_headers:
1434        env.Command(hdr, [], switch_hdr_action)
1435
1436Export('make_gpu_switching_dir')
1437
1438# all-isas -> all-deps -> all-environs -> all_targets
1439main.Alias('#all-isas', [])
1440main.Alias('#all-deps', '#all-isas')
1441
1442# Dummy target to ensure all environments are created before telling
1443# SCons what to actually make (the command line arguments).  We attach
1444# them to the dependence graph after the environments are complete.
1445ORIG_BUILD_TARGETS = list(BUILD_TARGETS) # force a copy; gets closure to work.
1446def environsComplete(target, source, env):
1447    for t in ORIG_BUILD_TARGETS:
1448        main.Depends('#all-targets', t)
1449
1450# Each build/* switching_dir attaches its *-environs target to #all-environs.
1451main.Append(BUILDERS = {'CompleteEnvirons' :
1452                        Builder(action=MakeAction(environsComplete, None))})
1453main.CompleteEnvirons('#all-environs', [])
1454
1455def doNothing(**ignored): pass
1456main.Append(BUILDERS = {'Dummy': Builder(action=MakeAction(doNothing, None))})
1457
1458# The final target to which all the original targets ultimately get attached.
1459main.Dummy('#all-targets', '#all-environs')
1460BUILD_TARGETS[:] = ['#all-targets']
1461
1462###################################################
1463#
1464# Define build environments for selected configurations.
1465#
1466###################################################
1467
1468for variant_path in variant_paths:
1469    if not GetOption('silent'):
1470        print "Building in", variant_path
1471
1472    # Make a copy of the build-root environment to use for this config.
1473    env = main.Clone()
1474    env['BUILDDIR'] = variant_path
1475
1476    # variant_dir is the tail component of build path, and is used to
1477    # determine the build parameters (e.g., 'ALPHA_SE')
1478    (build_root, variant_dir) = splitpath(variant_path)
1479
1480    # Set env variables according to the build directory config.
1481    sticky_vars.files = []
1482    # Variables for $BUILD_ROOT/$VARIANT_DIR are stored in
1483    # $BUILD_ROOT/variables/$VARIANT_DIR so you can nuke
1484    # $BUILD_ROOT/$VARIANT_DIR without losing your variables settings.
1485    current_vars_file = joinpath(build_root, 'variables', variant_dir)
1486    if isfile(current_vars_file):
1487        sticky_vars.files.append(current_vars_file)
1488        if not GetOption('silent'):
1489            print "Using saved variables file %s" % current_vars_file
1490    else:
1491        # Build dir-specific variables file doesn't exist.
1492
1493        # Make sure the directory is there so we can create it later
1494        opt_dir = dirname(current_vars_file)
1495        if not isdir(opt_dir):
1496            mkdir(opt_dir)
1497
1498        # Get default build variables from source tree.  Variables are
1499        # normally determined by name of $VARIANT_DIR, but can be
1500        # overridden by '--default=' arg on command line.
1501        default = GetOption('default')
1502        opts_dir = joinpath(main.root.abspath, 'build_opts')
1503        if default:
1504            default_vars_files = [joinpath(build_root, 'variables', default),
1505                                  joinpath(opts_dir, default)]
1506        else:
1507            default_vars_files = [joinpath(opts_dir, variant_dir)]
1508        existing_files = filter(isfile, default_vars_files)
1509        if existing_files:
1510            default_vars_file = existing_files[0]
1511            sticky_vars.files.append(default_vars_file)
1512            print "Variables file %s not found,\n  using defaults in %s" \
1513                  % (current_vars_file, default_vars_file)
1514        else:
1515            print "Error: cannot find variables file %s or " \
1516                  "default file(s) %s" \
1517                  % (current_vars_file, ' or '.join(default_vars_files))
1518            Exit(1)
1519
1520    # Apply current variable settings to env
1521    sticky_vars.Update(env)
1522
1523    help_texts["local_vars"] += \
1524        "Build variables for %s:\n" % variant_dir \
1525                 + sticky_vars.GenerateHelpText(env)
1526
1527    # Process variable settings.
1528
1529    if not have_fenv and env['USE_FENV']:
1530        print "Warning: <fenv.h> not available; " \
1531              "forcing USE_FENV to False in", variant_dir + "."
1532        env['USE_FENV'] = False
1533
1534    if not env['USE_FENV']:
1535        print "Warning: No IEEE FP rounding mode control in", variant_dir + "."
1536        print "         FP results may deviate slightly from other platforms."
1537
1538    if env['EFENCE']:
1539        env.Append(LIBS=['efence'])
1540
1541    if env['USE_KVM']:
1542        if not have_kvm:
1543            print "Warning: Can not enable KVM, host seems to lack KVM support"
1544            env['USE_KVM'] = False
1545        elif not is_isa_kvm_compatible(env['TARGET_ISA']):
1546            print "Info: KVM support disabled due to unsupported host and " \
1547                "target ISA combination"
1548            env['USE_KVM'] = False
1549
1550    if env['BUILD_GPU']:
1551        env.Append(CPPDEFINES=['BUILD_GPU'])
1552
1553    # Warn about missing optional functionality
1554    if env['USE_KVM']:
1555        if not main['HAVE_PERF_ATTR_EXCLUDE_HOST']:
1556            print "Warning: perf_event headers lack support for the " \
1557                "exclude_host attribute. KVM instruction counts will " \
1558                "be inaccurate."
1559
1560    # Save sticky variable settings back to current variables file
1561    sticky_vars.Save(current_vars_file, env)
1562
1563    if env['USE_SSE2']:
1564        env.Append(CCFLAGS=['-msse2'])
1565
1566    # The src/SConscript file sets up the build rules in 'env' according
1567    # to the configured variables.  It returns a list of environments,
1568    # one for each variant build (debug, opt, etc.)
1569    SConscript('src/SConscript', variant_dir = variant_path, exports = 'env')
1570
1571def pairwise(iterable):
1572    "s -> (s0,s1), (s1,s2), (s2, s3), ..."
1573    a, b = itertools.tee(iterable)
1574    b.next()
1575    return itertools.izip(a, b)
1576
1577# Create false dependencies so SCons will parse ISAs, establish
1578# dependencies, and setup the build Environments serially. Either
1579# SCons (likely) and/or our SConscripts (possibly) cannot cope with -j
1580# greater than 1. It appears to be standard race condition stuff; it
1581# doesn't always fail, but usually, and the behaviors are different.
1582# Every time I tried to remove this, builds would fail in some
1583# creative new way. So, don't do that. You'll want to, though, because
1584# tests/SConscript takes a long time to make its Environments.
1585for t1, t2 in pairwise(sorted(all_isa_deps.iterkeys())):
1586    main.Depends('#%s-deps'     % t2, '#%s-deps'     % t1)
1587    main.Depends('#%s-environs' % t2, '#%s-environs' % t1)
1588
1589# base help text
1590Help('''
1591Usage: scons [scons options] [build variables] [target(s)]
1592
1593Extra scons options:
1594%(options)s
1595
1596Global build variables:
1597%(global_vars)s
1598
1599%(local_vars)s
1600''' % help_texts)
1601