SConstruct revision 12013:755a563d1883
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', '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# 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
259
260style_message = """
261You're missing the gem5 style hook, which automatically checks your code
262against the gem5 style rules on %s.
263This script will now install the hook in your %s.
264Press enter to continue, or ctrl-c to abort: """
265
266mercurial_style_message = """
267You're missing the gem5 style hook, which automatically checks your code
268against the gem5 style rules on hg commit and qrefresh commands.
269This script will now install the hook in your .hg/hgrc file.
270Press enter to continue, or ctrl-c to abort: """
271
272git_style_message = """
273You're missing the gem5 style or commit message hook. These hooks help
274to ensure that your code follows gem5's style rules on git commit.
275This script will now install the hook in your .git/hooks/ directory.
276Press enter to continue, or ctrl-c to abort: """
277
278mercurial_style_upgrade_message = """
279Your Mercurial style hooks are not up-to-date. This script will now
280try to automatically update them. A backup of your hgrc will be saved
281in .hg/hgrc.old.
282Press enter to continue, or ctrl-c to abort: """
283
284mercurial_style_hook = """
285# The following lines were automatically added by gem5/SConstruct
286# to provide the gem5 style-checking hooks
287[extensions]
288hgstyle = %s/util/hgstyle.py
289
290[hooks]
291pretxncommit.style = python:hgstyle.check_style
292pre-qrefresh.style = python:hgstyle.check_style
293# End of SConstruct additions
294
295""" % (main.root.abspath)
296
297mercurial_lib_not_found = """
298Mercurial libraries cannot be found, ignoring style hook.  If
299you are a gem5 developer, please fix this and run the style
300hook. It is important.
301"""
302
303# Check for style hook and prompt for installation if it's not there.
304# Skip this if --ignore-style was specified, there's no interactive
305# terminal to prompt, or no recognized revision control system can be
306# found.
307ignore_style = GetOption('ignore_style') or not sys.stdin.isatty()
308
309# Try wire up Mercurial to the style hooks
310if not ignore_style and hgdir.exists():
311    style_hook = True
312    style_hooks = tuple()
313    hgrc = hgdir.File('hgrc')
314    hgrc_old = hgdir.File('hgrc.old')
315    try:
316        from mercurial import ui
317        ui = ui.ui()
318        ui.readconfig(hgrc.abspath)
319        style_hooks = (ui.config('hooks', 'pretxncommit.style', None),
320                       ui.config('hooks', 'pre-qrefresh.style', None))
321        style_hook = all(style_hooks)
322        style_extension = ui.config('extensions', 'style', None)
323    except ImportError:
324        print mercurial_lib_not_found
325
326    if "python:style.check_style" in style_hooks:
327        # Try to upgrade the style hooks
328        print mercurial_style_upgrade_message
329        # continue unless user does ctrl-c/ctrl-d etc.
330        try:
331            raw_input()
332        except:
333            print "Input exception, exiting scons.\n"
334            sys.exit(1)
335        shutil.copyfile(hgrc.abspath, hgrc_old.abspath)
336        re_style_hook = re.compile(r"^([^=#]+)\.style\s*=\s*([^#\s]+).*")
337        re_style_extension = re.compile("style\s*=\s*([^#\s]+).*")
338        old, new = open(hgrc_old.abspath, 'r'), open(hgrc.abspath, 'w')
339        for l in old:
340            m_hook = re_style_hook.match(l)
341            m_ext = re_style_extension.match(l)
342            if m_hook:
343                hook, check = m_hook.groups()
344                if check != "python:style.check_style":
345                    print "Warning: %s.style is using a non-default " \
346                        "checker: %s" % (hook, check)
347                if hook not in ("pretxncommit", "pre-qrefresh"):
348                    print "Warning: Updating unknown style hook: %s" % hook
349
350                l = "%s.style = python:hgstyle.check_style\n" % hook
351            elif m_ext and m_ext.group(1) == style_extension:
352                l = "hgstyle = %s/util/hgstyle.py\n" % main.root.abspath
353
354            new.write(l)
355    elif not style_hook:
356        print mercurial_style_message,
357        # continue unless user does ctrl-c/ctrl-d etc.
358        try:
359            raw_input()
360        except:
361            print "Input exception, exiting scons.\n"
362            sys.exit(1)
363        hgrc_path = '%s/.hg/hgrc' % main.root.abspath
364        print "Adding style hook to", hgrc_path, "\n"
365        try:
366            with open(hgrc_path, 'a') as f:
367                f.write(mercurial_style_hook)
368        except:
369            print "Error updating", hgrc_path
370            sys.exit(1)
371
372def install_git_style_hooks():
373    try:
374        gitdir = Dir(readCommand(
375            ["git", "rev-parse", "--git-dir"]).strip("\n"))
376    except Exception, e:
377        print "Warning: Failed to find git repo directory: %s" % e
378        return
379
380    git_hooks = gitdir.Dir("hooks")
381    def hook_exists(hook_name):
382        hook = git_hooks.File(hook_name)
383        return hook.exists()
384
385    def hook_install(hook_name, script):
386        hook = git_hooks.File(hook_name)
387        if hook.exists():
388            print "Warning: Can't install %s, hook already exists." % hook_name
389            return
390
391        if hook.islink():
392            print "Warning: Removing broken symlink for hook %s." % hook_name
393            os.unlink(hook.get_abspath())
394
395        if not git_hooks.exists():
396            mkdir(git_hooks.get_abspath())
397            git_hooks.clear()
398
399        abs_symlink_hooks = git_hooks.islink() and \
400            os.path.isabs(os.readlink(git_hooks.get_abspath()))
401
402        # Use a relative symlink if the hooks live in the source directory,
403        # and the hooks directory is not a symlink to an absolute path.
404        if hook.is_under(main.root) and not abs_symlink_hooks:
405            script_path = os.path.relpath(
406                os.path.realpath(script.get_abspath()),
407                os.path.realpath(hook.Dir(".").get_abspath()))
408        else:
409            script_path = script.get_abspath()
410
411        try:
412            os.symlink(script_path, hook.get_abspath())
413        except:
414            print "Error updating git %s hook" % hook_name
415            raise
416
417    if hook_exists("pre-commit") and hook_exists("commit-msg"):
418        return
419
420    print git_style_message,
421    try:
422        raw_input()
423    except:
424        print "Input exception, exiting scons.\n"
425        sys.exit(1)
426
427    git_style_script = File("util/git-pre-commit.py")
428    git_msg_script = File("ext/git-commit-msg")
429
430    hook_install("pre-commit", git_style_script)
431    hook_install("commit-msg", git_msg_script)
432
433# Try to wire up git to the style hooks
434if not ignore_style and main.root.Entry(".git").exists():
435    install_git_style_hooks()
436
437###################################################
438#
439# Figure out which configurations to set up based on the path(s) of
440# the target(s).
441#
442###################################################
443
444# Find default configuration & binary.
445Default(environ.get('M5_DEFAULT_BINARY', 'build/ALPHA/gem5.debug'))
446
447# helper function: find last occurrence of element in list
448def rfind(l, elt, offs = -1):
449    for i in range(len(l)+offs, 0, -1):
450        if l[i] == elt:
451            return i
452    raise ValueError, "element not found"
453
454# Take a list of paths (or SCons Nodes) and return a list with all
455# paths made absolute and ~-expanded.  Paths will be interpreted
456# relative to the launch directory unless a different root is provided
457def makePathListAbsolute(path_list, root=GetLaunchDir()):
458    return [abspath(joinpath(root, expanduser(str(p))))
459            for p in path_list]
460
461# Each target must have 'build' in the interior of the path; the
462# directory below this will determine the build parameters.  For
463# example, for target 'foo/bar/build/ALPHA_SE/arch/alpha/blah.do' we
464# recognize that ALPHA_SE specifies the configuration because it
465# follow 'build' in the build path.
466
467# The funky assignment to "[:]" is needed to replace the list contents
468# in place rather than reassign the symbol to a new list, which
469# doesn't work (obviously!).
470BUILD_TARGETS[:] = makePathListAbsolute(BUILD_TARGETS)
471
472# Generate a list of the unique build roots and configs that the
473# collected targets reference.
474variant_paths = []
475build_root = None
476for t in BUILD_TARGETS:
477    path_dirs = t.split('/')
478    try:
479        build_top = rfind(path_dirs, 'build', -2)
480    except:
481        print "Error: no non-leaf 'build' dir found on target path", t
482        Exit(1)
483    this_build_root = joinpath('/',*path_dirs[:build_top+1])
484    if not build_root:
485        build_root = this_build_root
486    else:
487        if this_build_root != build_root:
488            print "Error: build targets not under same build root\n"\
489                  "  %s\n  %s" % (build_root, this_build_root)
490            Exit(1)
491    variant_path = joinpath('/',*path_dirs[:build_top+2])
492    if variant_path not in variant_paths:
493        variant_paths.append(variant_path)
494
495# Make sure build_root exists (might not if this is the first build there)
496if not isdir(build_root):
497    mkdir(build_root)
498main['BUILDROOT'] = build_root
499
500Export('main')
501
502main.SConsignFile(joinpath(build_root, "sconsign"))
503
504# Default duplicate option is to use hard links, but this messes up
505# when you use emacs to edit a file in the target dir, as emacs moves
506# file to file~ then copies to file, breaking the link.  Symbolic
507# (soft) links work better.
508main.SetOption('duplicate', 'soft-copy')
509
510#
511# Set up global sticky variables... these are common to an entire build
512# tree (not specific to a particular build like ALPHA_SE)
513#
514
515global_vars_file = joinpath(build_root, 'variables.global')
516
517global_vars = Variables(global_vars_file, args=ARGUMENTS)
518
519global_vars.AddVariables(
520    ('CC', 'C compiler', environ.get('CC', main['CC'])),
521    ('CXX', 'C++ compiler', environ.get('CXX', main['CXX'])),
522    ('PROTOC', 'protoc tool', environ.get('PROTOC', 'protoc')),
523    ('BATCH', 'Use batch pool for build and tests', False),
524    ('BATCH_CMD', 'Batch pool submission command name', 'qdo'),
525    ('M5_BUILD_CACHE', 'Cache built objects in this directory', False),
526    ('EXTRAS', 'Add extra directories to the compilation', '')
527    )
528
529# Update main environment with values from ARGUMENTS & global_vars_file
530global_vars.Update(main)
531help_texts["global_vars"] += global_vars.GenerateHelpText(main)
532
533# Save sticky variable settings back to current variables file
534global_vars.Save(global_vars_file, main)
535
536# Parse EXTRAS variable to build list of all directories where we're
537# look for sources etc.  This list is exported as extras_dir_list.
538base_dir = main.srcdir.abspath
539if main['EXTRAS']:
540    extras_dir_list = makePathListAbsolute(main['EXTRAS'].split(':'))
541else:
542    extras_dir_list = []
543
544Export('base_dir')
545Export('extras_dir_list')
546
547# the ext directory should be on the #includes path
548main.Append(CPPPATH=[Dir('ext')])
549
550def strip_build_path(path, env):
551    path = str(path)
552    variant_base = env['BUILDROOT'] + os.path.sep
553    if path.startswith(variant_base):
554        path = path[len(variant_base):]
555    elif path.startswith('build/'):
556        path = path[6:]
557    return path
558
559# Generate a string of the form:
560#   common/path/prefix/src1, src2 -> tgt1, tgt2
561# to print while building.
562class Transform(object):
563    # all specific color settings should be here and nowhere else
564    tool_color = termcap.Normal
565    pfx_color = termcap.Yellow
566    srcs_color = termcap.Yellow + termcap.Bold
567    arrow_color = termcap.Blue + termcap.Bold
568    tgts_color = termcap.Yellow + termcap.Bold
569
570    def __init__(self, tool, max_sources=99):
571        self.format = self.tool_color + (" [%8s] " % tool) \
572                      + self.pfx_color + "%s" \
573                      + self.srcs_color + "%s" \
574                      + self.arrow_color + " -> " \
575                      + self.tgts_color + "%s" \
576                      + termcap.Normal
577        self.max_sources = max_sources
578
579    def __call__(self, target, source, env, for_signature=None):
580        # truncate source list according to max_sources param
581        source = source[0:self.max_sources]
582        def strip(f):
583            return strip_build_path(str(f), env)
584        if len(source) > 0:
585            srcs = map(strip, source)
586        else:
587            srcs = ['']
588        tgts = map(strip, target)
589        # surprisingly, os.path.commonprefix is a dumb char-by-char string
590        # operation that has nothing to do with paths.
591        com_pfx = os.path.commonprefix(srcs + tgts)
592        com_pfx_len = len(com_pfx)
593        if com_pfx:
594            # do some cleanup and sanity checking on common prefix
595            if com_pfx[-1] == ".":
596                # prefix matches all but file extension: ok
597                # back up one to change 'foo.cc -> o' to 'foo.cc -> .o'
598                com_pfx = com_pfx[0:-1]
599            elif com_pfx[-1] == "/":
600                # common prefix is directory path: OK
601                pass
602            else:
603                src0_len = len(srcs[0])
604                tgt0_len = len(tgts[0])
605                if src0_len == com_pfx_len:
606                    # source is a substring of target, OK
607                    pass
608                elif tgt0_len == com_pfx_len:
609                    # target is a substring of source, need to back up to
610                    # avoid empty string on RHS of arrow
611                    sep_idx = com_pfx.rfind(".")
612                    if sep_idx != -1:
613                        com_pfx = com_pfx[0:sep_idx]
614                    else:
615                        com_pfx = ''
616                elif src0_len > com_pfx_len and srcs[0][com_pfx_len] == ".":
617                    # still splitting at file extension: ok
618                    pass
619                else:
620                    # probably a fluke; ignore it
621                    com_pfx = ''
622        # recalculate length in case com_pfx was modified
623        com_pfx_len = len(com_pfx)
624        def fmt(files):
625            f = map(lambda s: s[com_pfx_len:], files)
626            return ', '.join(f)
627        return self.format % (com_pfx, fmt(srcs), fmt(tgts))
628
629Export('Transform')
630
631# enable the regression script to use the termcap
632main['TERMCAP'] = termcap
633
634if GetOption('verbose'):
635    def MakeAction(action, string, *args, **kwargs):
636        return Action(action, *args, **kwargs)
637else:
638    MakeAction = Action
639    main['CCCOMSTR']        = Transform("CC")
640    main['CXXCOMSTR']       = Transform("CXX")
641    main['ASCOMSTR']        = Transform("AS")
642    main['ARCOMSTR']        = Transform("AR", 0)
643    main['LINKCOMSTR']      = Transform("LINK", 0)
644    main['SHLINKCOMSTR']    = Transform("SHLINK", 0)
645    main['RANLIBCOMSTR']    = Transform("RANLIB", 0)
646    main['M4COMSTR']        = Transform("M4")
647    main['SHCCCOMSTR']      = Transform("SHCC")
648    main['SHCXXCOMSTR']     = Transform("SHCXX")
649Export('MakeAction')
650
651# Initialize the Link-Time Optimization (LTO) flags
652main['LTO_CCFLAGS'] = []
653main['LTO_LDFLAGS'] = []
654
655# According to the readme, tcmalloc works best if the compiler doesn't
656# assume that we're using the builtin malloc and friends. These flags
657# are compiler-specific, so we need to set them after we detect which
658# compiler we're using.
659main['TCMALLOC_CCFLAGS'] = []
660
661CXX_version = readCommand([main['CXX'],'--version'], exception=False)
662CXX_V = readCommand([main['CXX'],'-V'], exception=False)
663
664main['GCC'] = CXX_version and CXX_version.find('g++') >= 0
665main['CLANG'] = CXX_version and CXX_version.find('clang') >= 0
666if main['GCC'] + main['CLANG'] > 1:
667    print 'Error: How can we have two at the same time?'
668    Exit(1)
669
670# Set up default C++ compiler flags
671if main['GCC'] or main['CLANG']:
672    # As gcc and clang share many flags, do the common parts here
673    main.Append(CCFLAGS=['-pipe'])
674    main.Append(CCFLAGS=['-fno-strict-aliasing'])
675    # Enable -Wall and -Wextra and then disable the few warnings that
676    # we consistently violate
677    main.Append(CCFLAGS=['-Wall', '-Wundef', '-Wextra',
678                         '-Wno-sign-compare', '-Wno-unused-parameter'])
679    # We always compile using C++11
680    main.Append(CXXFLAGS=['-std=c++11'])
681    if sys.platform.startswith('freebsd'):
682        main.Append(CCFLAGS=['-I/usr/local/include'])
683        main.Append(CXXFLAGS=['-I/usr/local/include'])
684
685    main['FILTER_PSHLINKFLAGS'] = lambda x: str(x).replace(' -shared', '')
686    main['PSHLINKFLAGS'] = main.subst('${FILTER_PSHLINKFLAGS(SHLINKFLAGS)}')
687    main['PLINKFLAGS'] = main.subst('${LINKFLAGS}')
688    shared_partial_flags = ['-r', '-nostdlib']
689    main.Append(PSHLINKFLAGS=shared_partial_flags)
690    main.Append(PLINKFLAGS=shared_partial_flags)
691else:
692    print termcap.Yellow + termcap.Bold + 'Error' + termcap.Normal,
693    print "Don't know what compiler options to use for your compiler."
694    print termcap.Yellow + '       compiler:' + termcap.Normal, main['CXX']
695    print termcap.Yellow + '       version:' + termcap.Normal,
696    if not CXX_version:
697        print termcap.Yellow + termcap.Bold + "COMMAND NOT FOUND!" +\
698               termcap.Normal
699    else:
700        print CXX_version.replace('\n', '<nl>')
701    print "       If you're trying to use a compiler other than GCC"
702    print "       or clang, there appears to be something wrong with your"
703    print "       environment."
704    print "       "
705    print "       If you are trying to use a compiler other than those listed"
706    print "       above you will need to ease fix SConstruct and "
707    print "       src/SConscript to support that compiler."
708    Exit(1)
709
710if main['GCC']:
711    # Check for a supported version of gcc. >= 4.8 is chosen for its
712    # level of c++11 support. See
713    # http://gcc.gnu.org/projects/cxx0x.html for details.
714    gcc_version = readCommand([main['CXX'], '-dumpversion'], exception=False)
715    if compareVersions(gcc_version, "4.8") < 0:
716        print 'Error: gcc version 4.8 or newer required.'
717        print '       Installed version:', gcc_version
718        Exit(1)
719
720    main['GCC_VERSION'] = gcc_version
721
722    # gcc from version 4.8 and above generates "rep; ret" instructions
723    # to avoid performance penalties on certain AMD chips. Older
724    # assemblers detect this as an error, "Error: expecting string
725    # instruction after `rep'"
726    as_version_raw = readCommand([main['AS'], '-v', '/dev/null',
727                                  '-o', '/dev/null'],
728                                 exception=False).split()
729
730    # version strings may contain extra distro-specific
731    # qualifiers, so play it safe and keep only what comes before
732    # the first hyphen
733    as_version = as_version_raw[-1].split('-')[0] if as_version_raw else None
734
735    if not as_version or compareVersions(as_version, "2.23") < 0:
736        print termcap.Yellow + termcap.Bold + \
737            'Warning: This combination of gcc and binutils have' + \
738            ' known incompatibilities.\n' + \
739            '         If you encounter build problems, please update ' + \
740            'binutils to 2.23.' + \
741            termcap.Normal
742
743    # Make sure we warn if the user has requested to compile with the
744    # Undefined Benahvior Sanitizer and this version of gcc does not
745    # support it.
746    if GetOption('with_ubsan') and \
747            compareVersions(gcc_version, '4.9') < 0:
748        print termcap.Yellow + termcap.Bold + \
749            'Warning: UBSan is only supported using gcc 4.9 and later.' + \
750            termcap.Normal
751
752    # Add the appropriate Link-Time Optimization (LTO) flags
753    # unless LTO is explicitly turned off. Note that these flags
754    # are only used by the fast target.
755    if not GetOption('no_lto'):
756        # Pass the LTO flag when compiling to produce GIMPLE
757        # output, we merely create the flags here and only append
758        # them later
759        main['LTO_CCFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
760
761        # Use the same amount of jobs for LTO as we are running
762        # scons with
763        main['LTO_LDFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
764
765    main.Append(TCMALLOC_CCFLAGS=['-fno-builtin-malloc', '-fno-builtin-calloc',
766                                  '-fno-builtin-realloc', '-fno-builtin-free'])
767
768    # add option to check for undeclared overrides
769    if compareVersions(gcc_version, "5.0") > 0:
770        main.Append(CCFLAGS=['-Wno-error=suggest-override'])
771
772elif main['CLANG']:
773    # Check for a supported version of clang, >= 3.1 is needed to
774    # support similar features as gcc 4.8. See
775    # http://clang.llvm.org/cxx_status.html for details
776    clang_version_re = re.compile(".* version (\d+\.\d+)")
777    clang_version_match = clang_version_re.search(CXX_version)
778    if (clang_version_match):
779        clang_version = clang_version_match.groups()[0]
780        if compareVersions(clang_version, "3.1") < 0:
781            print 'Error: clang version 3.1 or newer required.'
782            print '       Installed version:', clang_version
783            Exit(1)
784    else:
785        print 'Error: Unable to determine clang version.'
786        Exit(1)
787
788    # clang has a few additional warnings that we disable, extraneous
789    # parantheses are allowed due to Ruby's printing of the AST,
790    # finally self assignments are allowed as the generated CPU code
791    # is relying on this
792    main.Append(CCFLAGS=['-Wno-parentheses',
793                         '-Wno-self-assign',
794                         # Some versions of libstdc++ (4.8?) seem to
795                         # use struct hash and class hash
796                         # interchangeably.
797                         '-Wno-mismatched-tags',
798                         ])
799
800    main.Append(TCMALLOC_CCFLAGS=['-fno-builtin'])
801
802    # On Mac OS X/Darwin we need to also use libc++ (part of XCode) as
803    # opposed to libstdc++, as the later is dated.
804    if sys.platform == "darwin":
805        main.Append(CXXFLAGS=['-stdlib=libc++'])
806        main.Append(LIBS=['c++'])
807
808    # On FreeBSD we need libthr.
809    if sys.platform.startswith('freebsd'):
810        main.Append(LIBS=['thr'])
811
812else:
813    print termcap.Yellow + termcap.Bold + 'Error' + termcap.Normal,
814    print "Don't know what compiler options to use for your compiler."
815    print termcap.Yellow + '       compiler:' + termcap.Normal, main['CXX']
816    print termcap.Yellow + '       version:' + termcap.Normal,
817    if not CXX_version:
818        print termcap.Yellow + termcap.Bold + "COMMAND NOT FOUND!" +\
819               termcap.Normal
820    else:
821        print CXX_version.replace('\n', '<nl>')
822    print "       If you're trying to use a compiler other than GCC"
823    print "       or clang, there appears to be something wrong with your"
824    print "       environment."
825    print "       "
826    print "       If you are trying to use a compiler other than those listed"
827    print "       above you will need to ease fix SConstruct and "
828    print "       src/SConscript to support that compiler."
829    Exit(1)
830
831# Set up common yacc/bison flags (needed for Ruby)
832main['YACCFLAGS'] = '-d'
833main['YACCHXXFILESUFFIX'] = '.hh'
834
835# Do this after we save setting back, or else we'll tack on an
836# extra 'qdo' every time we run scons.
837if main['BATCH']:
838    main['CC']     = main['BATCH_CMD'] + ' ' + main['CC']
839    main['CXX']    = main['BATCH_CMD'] + ' ' + main['CXX']
840    main['AS']     = main['BATCH_CMD'] + ' ' + main['AS']
841    main['AR']     = main['BATCH_CMD'] + ' ' + main['AR']
842    main['RANLIB'] = main['BATCH_CMD'] + ' ' + main['RANLIB']
843
844if sys.platform == 'cygwin':
845    # cygwin has some header file issues...
846    main.Append(CCFLAGS=["-Wno-uninitialized"])
847
848# Check for the protobuf compiler
849protoc_version = readCommand([main['PROTOC'], '--version'],
850                             exception='').split()
851
852# First two words should be "libprotoc x.y.z"
853if len(protoc_version) < 2 or protoc_version[0] != 'libprotoc':
854    print termcap.Yellow + termcap.Bold + \
855        'Warning: Protocol buffer compiler (protoc) not found.\n' + \
856        '         Please install protobuf-compiler for tracing support.' + \
857        termcap.Normal
858    main['PROTOC'] = False
859else:
860    # Based on the availability of the compress stream wrappers,
861    # require 2.1.0
862    min_protoc_version = '2.1.0'
863    if compareVersions(protoc_version[1], min_protoc_version) < 0:
864        print termcap.Yellow + termcap.Bold + \
865            'Warning: protoc version', min_protoc_version, \
866            'or newer required.\n' + \
867            '         Installed version:', protoc_version[1], \
868            termcap.Normal
869        main['PROTOC'] = False
870    else:
871        # Attempt to determine the appropriate include path and
872        # library path using pkg-config, that means we also need to
873        # check for pkg-config. Note that it is possible to use
874        # protobuf without the involvement of pkg-config. Later on we
875        # check go a library config check and at that point the test
876        # will fail if libprotobuf cannot be found.
877        if readCommand(['pkg-config', '--version'], exception=''):
878            try:
879                # Attempt to establish what linking flags to add for protobuf
880                # using pkg-config
881                main.ParseConfig('pkg-config --cflags --libs-only-L protobuf')
882            except:
883                print termcap.Yellow + termcap.Bold + \
884                    'Warning: pkg-config could not get protobuf flags.' + \
885                    termcap.Normal
886
887
888# Check for 'timeout' from GNU coreutils. If present, regressions will
889# be run with a time limit. We require version 8.13 since we rely on
890# support for the '--foreground' option.
891if sys.platform.startswith('freebsd'):
892    timeout_lines = readCommand(['gtimeout', '--version'],
893                                exception='').splitlines()
894else:
895    timeout_lines = readCommand(['timeout', '--version'],
896                                exception='').splitlines()
897# Get the first line and tokenize it
898timeout_version = timeout_lines[0].split() if timeout_lines else []
899main['TIMEOUT'] =  timeout_version and \
900    compareVersions(timeout_version[-1], '8.13') >= 0
901
902# Add a custom Check function to test for structure members.
903def CheckMember(context, include, decl, member, include_quotes="<>"):
904    context.Message("Checking for member %s in %s..." %
905                    (member, decl))
906    text = """
907#include %(header)s
908int main(){
909  %(decl)s test;
910  (void)test.%(member)s;
911  return 0;
912};
913""" % { "header" : include_quotes[0] + include + include_quotes[1],
914        "decl" : decl,
915        "member" : member,
916        }
917
918    ret = context.TryCompile(text, extension=".cc")
919    context.Result(ret)
920    return ret
921
922# Platform-specific configuration.  Note again that we assume that all
923# builds under a given build root run on the same host platform.
924conf = Configure(main,
925                 conf_dir = joinpath(build_root, '.scons_config'),
926                 log_file = joinpath(build_root, 'scons_config.log'),
927                 custom_tests = {
928        'CheckMember' : CheckMember,
929        })
930
931# Check if we should compile a 64 bit binary on Mac OS X/Darwin
932try:
933    import platform
934    uname = platform.uname()
935    if uname[0] == 'Darwin' and compareVersions(uname[2], '9.0.0') >= 0:
936        if int(readCommand('sysctl -n hw.cpu64bit_capable')[0]):
937            main.Append(CCFLAGS=['-arch', 'x86_64'])
938            main.Append(CFLAGS=['-arch', 'x86_64'])
939            main.Append(LINKFLAGS=['-arch', 'x86_64'])
940            main.Append(ASFLAGS=['-arch', 'x86_64'])
941except:
942    pass
943
944# Recent versions of scons substitute a "Null" object for Configure()
945# when configuration isn't necessary, e.g., if the "--help" option is
946# present.  Unfortuantely this Null object always returns false,
947# breaking all our configuration checks.  We replace it with our own
948# more optimistic null object that returns True instead.
949if not conf:
950    def NullCheck(*args, **kwargs):
951        return True
952
953    class NullConf:
954        def __init__(self, env):
955            self.env = env
956        def Finish(self):
957            return self.env
958        def __getattr__(self, mname):
959            return NullCheck
960
961    conf = NullConf(main)
962
963# Cache build files in the supplied directory.
964if main['M5_BUILD_CACHE']:
965    print 'Using build cache located at', main['M5_BUILD_CACHE']
966    CacheDir(main['M5_BUILD_CACHE'])
967
968main['USE_PYTHON'] = not GetOption('without_python')
969if main['USE_PYTHON']:
970    # Find Python include and library directories for embedding the
971    # interpreter. We rely on python-config to resolve the appropriate
972    # includes and linker flags. ParseConfig does not seem to understand
973    # the more exotic linker flags such as -Xlinker and -export-dynamic so
974    # we add them explicitly below. If you want to link in an alternate
975    # version of python, see above for instructions on how to invoke
976    # scons with the appropriate PATH set.
977    #
978    # First we check if python2-config exists, else we use python-config
979    python_config = readCommand(['which', 'python2-config'],
980                                exception='').strip()
981    if not os.path.exists(python_config):
982        python_config = readCommand(['which', 'python-config'],
983                                    exception='').strip()
984    py_includes = readCommand([python_config, '--includes'],
985                              exception='').split()
986    # Strip the -I from the include folders before adding them to the
987    # CPPPATH
988    main.Append(CPPPATH=map(lambda inc: inc[2:], py_includes))
989
990    # Read the linker flags and split them into libraries and other link
991    # flags. The libraries are added later through the call the CheckLib.
992    py_ld_flags = readCommand([python_config, '--ldflags'],
993        exception='').split()
994    py_libs = []
995    for lib in py_ld_flags:
996         if not lib.startswith('-l'):
997             main.Append(LINKFLAGS=[lib])
998         else:
999             lib = lib[2:]
1000             if lib not in py_libs:
1001                 py_libs.append(lib)
1002
1003    # verify that this stuff works
1004    if not conf.CheckHeader('Python.h', '<>'):
1005        print "Error: can't find Python.h header in", py_includes
1006        print "Install Python headers (package python-dev on Ubuntu and RedHat)"
1007        Exit(1)
1008
1009    for lib in py_libs:
1010        if not conf.CheckLib(lib):
1011            print "Error: can't find library %s required by python" % lib
1012            Exit(1)
1013
1014# On Solaris you need to use libsocket for socket ops
1015if not conf.CheckLibWithHeader(None, 'sys/socket.h', 'C++', 'accept(0,0,0);'):
1016   if not conf.CheckLibWithHeader('socket', 'sys/socket.h', 'C++', 'accept(0,0,0);'):
1017       print "Can't find library with socket calls (e.g. accept())"
1018       Exit(1)
1019
1020# Check for zlib.  If the check passes, libz will be automatically
1021# added to the LIBS environment variable.
1022if not conf.CheckLibWithHeader('z', 'zlib.h', 'C++','zlibVersion();'):
1023    print 'Error: did not find needed zlib compression library '\
1024          'and/or zlib.h header file.'
1025    print '       Please install zlib and try again.'
1026    Exit(1)
1027
1028# If we have the protobuf compiler, also make sure we have the
1029# development libraries. If the check passes, libprotobuf will be
1030# automatically added to the LIBS environment variable. After
1031# this, we can use the HAVE_PROTOBUF flag to determine if we have
1032# got both protoc and libprotobuf available.
1033main['HAVE_PROTOBUF'] = main['PROTOC'] and \
1034    conf.CheckLibWithHeader('protobuf', 'google/protobuf/message.h',
1035                            'C++', 'GOOGLE_PROTOBUF_VERIFY_VERSION;')
1036
1037# If we have the compiler but not the library, print another warning.
1038if main['PROTOC'] and not main['HAVE_PROTOBUF']:
1039    print termcap.Yellow + termcap.Bold + \
1040        'Warning: did not find protocol buffer library and/or headers.\n' + \
1041    '       Please install libprotobuf-dev for tracing support.' + \
1042    termcap.Normal
1043
1044# Check for librt.
1045have_posix_clock = \
1046    conf.CheckLibWithHeader(None, 'time.h', 'C',
1047                            'clock_nanosleep(0,0,NULL,NULL);') or \
1048    conf.CheckLibWithHeader('rt', 'time.h', 'C',
1049                            'clock_nanosleep(0,0,NULL,NULL);')
1050
1051have_posix_timers = \
1052    conf.CheckLibWithHeader([None, 'rt'], [ 'time.h', 'signal.h' ], 'C',
1053                            'timer_create(CLOCK_MONOTONIC, NULL, NULL);')
1054
1055if not GetOption('without_tcmalloc'):
1056    if conf.CheckLib('tcmalloc'):
1057        main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
1058    elif conf.CheckLib('tcmalloc_minimal'):
1059        main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
1060    else:
1061        print termcap.Yellow + termcap.Bold + \
1062              "You can get a 12% performance improvement by "\
1063              "installing tcmalloc (libgoogle-perftools-dev package "\
1064              "on Ubuntu or RedHat)." + termcap.Normal
1065
1066
1067# Detect back trace implementations. The last implementation in the
1068# list will be used by default.
1069backtrace_impls = [ "none" ]
1070
1071if conf.CheckLibWithHeader(None, 'execinfo.h', 'C',
1072                           'backtrace_symbols_fd((void*)0, 0, 0);'):
1073    backtrace_impls.append("glibc")
1074elif conf.CheckLibWithHeader('execinfo', 'execinfo.h', 'C',
1075                           'backtrace_symbols_fd((void*)0, 0, 0);'):
1076    # NetBSD and FreeBSD need libexecinfo.
1077    backtrace_impls.append("glibc")
1078    main.Append(LIBS=['execinfo'])
1079
1080if backtrace_impls[-1] == "none":
1081    default_backtrace_impl = "none"
1082    print termcap.Yellow + termcap.Bold + \
1083        "No suitable back trace implementation found." + \
1084        termcap.Normal
1085
1086if not have_posix_clock:
1087    print "Can't find library for POSIX clocks."
1088
1089# Check for <fenv.h> (C99 FP environment control)
1090have_fenv = conf.CheckHeader('fenv.h', '<>')
1091if not have_fenv:
1092    print "Warning: Header file <fenv.h> not found."
1093    print "         This host has no IEEE FP rounding mode control."
1094
1095# Check if we should enable KVM-based hardware virtualization. The API
1096# we rely on exists since version 2.6.36 of the kernel, but somehow
1097# the KVM_API_VERSION does not reflect the change. We test for one of
1098# the types as a fall back.
1099have_kvm = conf.CheckHeader('linux/kvm.h', '<>')
1100if not have_kvm:
1101    print "Info: Compatible header file <linux/kvm.h> not found, " \
1102        "disabling KVM support."
1103
1104# x86 needs support for xsave. We test for the structure here since we
1105# won't be able to run new tests by the time we know which ISA we're
1106# targeting.
1107have_kvm_xsave = conf.CheckTypeSize('struct kvm_xsave',
1108                                    '#include <linux/kvm.h>') != 0
1109
1110# Check if the requested target ISA is compatible with the host
1111def is_isa_kvm_compatible(isa):
1112    try:
1113        import platform
1114        host_isa = platform.machine()
1115    except:
1116        print "Warning: Failed to determine host ISA."
1117        return False
1118
1119    if not have_posix_timers:
1120        print "Warning: Can not enable KVM, host seems to lack support " \
1121            "for POSIX timers"
1122        return False
1123
1124    if isa == "arm":
1125        return host_isa in ( "armv7l", "aarch64" )
1126    elif isa == "x86":
1127        if host_isa != "x86_64":
1128            return False
1129
1130        if not have_kvm_xsave:
1131            print "KVM on x86 requires xsave support in kernel headers."
1132            return False
1133
1134        return True
1135    else:
1136        return False
1137
1138
1139# Check if the exclude_host attribute is available. We want this to
1140# get accurate instruction counts in KVM.
1141main['HAVE_PERF_ATTR_EXCLUDE_HOST'] = conf.CheckMember(
1142    'linux/perf_event.h', 'struct perf_event_attr', 'exclude_host')
1143
1144
1145######################################################################
1146#
1147# Finish the configuration
1148#
1149main = conf.Finish()
1150
1151######################################################################
1152#
1153# Collect all non-global variables
1154#
1155
1156# Define the universe of supported ISAs
1157all_isa_list = [ ]
1158all_gpu_isa_list = [ ]
1159Export('all_isa_list')
1160Export('all_gpu_isa_list')
1161
1162class CpuModel(object):
1163    '''The CpuModel class encapsulates everything the ISA parser needs to
1164    know about a particular CPU model.'''
1165
1166    # Dict of available CPU model objects.  Accessible as CpuModel.dict.
1167    dict = {}
1168
1169    # Constructor.  Automatically adds models to CpuModel.dict.
1170    def __init__(self, name, default=False):
1171        self.name = name           # name of model
1172
1173        # This cpu is enabled by default
1174        self.default = default
1175
1176        # Add self to dict
1177        if name in CpuModel.dict:
1178            raise AttributeError, "CpuModel '%s' already registered" % name
1179        CpuModel.dict[name] = self
1180
1181Export('CpuModel')
1182
1183# Sticky variables get saved in the variables file so they persist from
1184# one invocation to the next (unless overridden, in which case the new
1185# value becomes sticky).
1186sticky_vars = Variables(args=ARGUMENTS)
1187Export('sticky_vars')
1188
1189# Sticky variables that should be exported
1190export_vars = []
1191Export('export_vars')
1192
1193# For Ruby
1194all_protocols = []
1195Export('all_protocols')
1196protocol_dirs = []
1197Export('protocol_dirs')
1198slicc_includes = []
1199Export('slicc_includes')
1200
1201# Walk the tree and execute all SConsopts scripts that wil add to the
1202# above variables
1203if GetOption('verbose'):
1204    print "Reading SConsopts"
1205for bdir in [ base_dir ] + extras_dir_list:
1206    if not isdir(bdir):
1207        print "Error: directory '%s' does not exist" % bdir
1208        Exit(1)
1209    for root, dirs, files in os.walk(bdir):
1210        if 'SConsopts' in files:
1211            if GetOption('verbose'):
1212                print "Reading", joinpath(root, 'SConsopts')
1213            SConscript(joinpath(root, 'SConsopts'))
1214
1215all_isa_list.sort()
1216all_gpu_isa_list.sort()
1217
1218sticky_vars.AddVariables(
1219    EnumVariable('TARGET_ISA', 'Target ISA', 'alpha', all_isa_list),
1220    EnumVariable('TARGET_GPU_ISA', 'Target GPU ISA', 'hsail', all_gpu_isa_list),
1221    ListVariable('CPU_MODELS', 'CPU models',
1222                 sorted(n for n,m in CpuModel.dict.iteritems() if m.default),
1223                 sorted(CpuModel.dict.keys())),
1224    BoolVariable('EFENCE', 'Link with Electric Fence malloc debugger',
1225                 False),
1226    BoolVariable('SS_COMPATIBLE_FP',
1227                 'Make floating-point results compatible with SimpleScalar',
1228                 False),
1229    BoolVariable('USE_SSE2',
1230                 'Compile for SSE2 (-msse2) to get IEEE FP on x86 hosts',
1231                 False),
1232    BoolVariable('USE_POSIX_CLOCK', 'Use POSIX Clocks', have_posix_clock),
1233    BoolVariable('USE_FENV', 'Use <fenv.h> IEEE mode control', have_fenv),
1234    BoolVariable('CP_ANNOTATE', 'Enable critical path annotation capability', False),
1235    BoolVariable('USE_KVM', 'Enable hardware virtualized (KVM) CPU models', have_kvm),
1236    BoolVariable('BUILD_GPU', 'Build the compute-GPU model', False),
1237    EnumVariable('PROTOCOL', 'Coherence protocol for Ruby', 'None',
1238                  all_protocols),
1239    EnumVariable('BACKTRACE_IMPL', 'Post-mortem dump implementation',
1240                 backtrace_impls[-1], backtrace_impls)
1241    )
1242
1243# These variables get exported to #defines in config/*.hh (see src/SConscript).
1244export_vars += ['USE_FENV', 'SS_COMPATIBLE_FP', 'TARGET_ISA', 'TARGET_GPU_ISA',
1245                'CP_ANNOTATE', 'USE_POSIX_CLOCK', 'USE_KVM', 'PROTOCOL',
1246                'HAVE_PROTOBUF', 'HAVE_PERF_ATTR_EXCLUDE_HOST']
1247
1248###################################################
1249#
1250# Define a SCons builder for configuration flag headers.
1251#
1252###################################################
1253
1254# This function generates a config header file that #defines the
1255# variable symbol to the current variable setting (0 or 1).  The source
1256# operands are the name of the variable and a Value node containing the
1257# value of the variable.
1258def build_config_file(target, source, env):
1259    (variable, value) = [s.get_contents() for s in source]
1260    f = file(str(target[0]), 'w')
1261    print >> f, '#define', variable, value
1262    f.close()
1263    return None
1264
1265# Combine the two functions into a scons Action object.
1266config_action = MakeAction(build_config_file, Transform("CONFIG H", 2))
1267
1268# The emitter munges the source & target node lists to reflect what
1269# we're really doing.
1270def config_emitter(target, source, env):
1271    # extract variable name from Builder arg
1272    variable = str(target[0])
1273    # True target is config header file
1274    target = joinpath('config', variable.lower() + '.hh')
1275    val = env[variable]
1276    if isinstance(val, bool):
1277        # Force value to 0/1
1278        val = int(val)
1279    elif isinstance(val, str):
1280        val = '"' + val + '"'
1281
1282    # Sources are variable name & value (packaged in SCons Value nodes)
1283    return ([target], [Value(variable), Value(val)])
1284
1285config_builder = Builder(emitter = config_emitter, action = config_action)
1286
1287main.Append(BUILDERS = { 'ConfigFile' : config_builder })
1288
1289###################################################
1290#
1291# Builders for static and shared partially linked object files.
1292#
1293###################################################
1294
1295partial_static_builder = Builder(action=SCons.Defaults.LinkAction,
1296                                 src_suffix='$OBJSUFFIX',
1297                                 src_builder=['StaticObject', 'Object'],
1298                                 LINKFLAGS='$PLINKFLAGS',
1299                                 LIBS='')
1300
1301def partial_shared_emitter(target, source, env):
1302    for tgt in target:
1303        tgt.attributes.shared = 1
1304    return (target, source)
1305partial_shared_builder = Builder(action=SCons.Defaults.ShLinkAction,
1306                                 emitter=partial_shared_emitter,
1307                                 src_suffix='$SHOBJSUFFIX',
1308                                 src_builder='SharedObject',
1309                                 SHLINKFLAGS='$PSHLINKFLAGS',
1310                                 LIBS='')
1311
1312main.Append(BUILDERS = { 'PartialShared' : partial_shared_builder,
1313                         'PartialStatic' : partial_static_builder })
1314
1315# builds in ext are shared across all configs in the build root.
1316ext_dir = abspath(joinpath(str(main.root), 'ext'))
1317for root, dirs, files in os.walk(ext_dir):
1318    if 'SConscript' in files:
1319        build_dir = os.path.relpath(root, ext_dir)
1320        main.SConscript(joinpath(root, 'SConscript'),
1321                        variant_dir=joinpath(build_root, build_dir))
1322
1323main.Prepend(CPPPATH=Dir('ext/pybind11/include/'))
1324
1325###################################################
1326#
1327# This function is used to set up a directory with switching headers
1328#
1329###################################################
1330
1331main['ALL_ISA_LIST'] = all_isa_list
1332main['ALL_GPU_ISA_LIST'] = all_gpu_isa_list
1333def make_switching_dir(dname, switch_headers, env):
1334    # Generate the header.  target[0] is the full path of the output
1335    # header to generate.  'source' is a dummy variable, since we get the
1336    # list of ISAs from env['ALL_ISA_LIST'].
1337    def gen_switch_hdr(target, source, env):
1338        fname = str(target[0])
1339        isa = env['TARGET_ISA'].lower()
1340        try:
1341            f = open(fname, 'w')
1342            print >>f, '#include "%s/%s/%s"' % (dname, isa, basename(fname))
1343            f.close()
1344        except IOError:
1345            print "Failed to create %s" % fname
1346            raise
1347
1348    # Build SCons Action object. 'varlist' specifies env vars that this
1349    # action depends on; when env['ALL_ISA_LIST'] changes these actions
1350    # should get re-executed.
1351    switch_hdr_action = MakeAction(gen_switch_hdr,
1352                          Transform("GENERATE"), varlist=['ALL_ISA_LIST'])
1353
1354    # Instantiate actions for each header
1355    for hdr in switch_headers:
1356        env.Command(hdr, [], switch_hdr_action)
1357
1358Export('make_switching_dir')
1359
1360def make_gpu_switching_dir(dname, switch_headers, env):
1361    # Generate the header.  target[0] is the full path of the output
1362    # header to generate.  'source' is a dummy variable, since we get the
1363    # list of ISAs from env['ALL_ISA_LIST'].
1364    def gen_switch_hdr(target, source, env):
1365        fname = str(target[0])
1366
1367        isa = env['TARGET_GPU_ISA'].lower()
1368
1369        try:
1370            f = open(fname, 'w')
1371            print >>f, '#include "%s/%s/%s"' % (dname, isa, basename(fname))
1372            f.close()
1373        except IOError:
1374            print "Failed to create %s" % fname
1375            raise
1376
1377    # Build SCons Action object. 'varlist' specifies env vars that this
1378    # action depends on; when env['ALL_ISA_LIST'] changes these actions
1379    # should get re-executed.
1380    switch_hdr_action = MakeAction(gen_switch_hdr,
1381                          Transform("GENERATE"), varlist=['ALL_ISA_GPU_LIST'])
1382
1383    # Instantiate actions for each header
1384    for hdr in switch_headers:
1385        env.Command(hdr, [], switch_hdr_action)
1386
1387Export('make_gpu_switching_dir')
1388
1389# all-isas -> all-deps -> all-environs -> all_targets
1390main.Alias('#all-isas', [])
1391main.Alias('#all-deps', '#all-isas')
1392
1393# Dummy target to ensure all environments are created before telling
1394# SCons what to actually make (the command line arguments).  We attach
1395# them to the dependence graph after the environments are complete.
1396ORIG_BUILD_TARGETS = list(BUILD_TARGETS) # force a copy; gets closure to work.
1397def environsComplete(target, source, env):
1398    for t in ORIG_BUILD_TARGETS:
1399        main.Depends('#all-targets', t)
1400
1401# Each build/* switching_dir attaches its *-environs target to #all-environs.
1402main.Append(BUILDERS = {'CompleteEnvirons' :
1403                        Builder(action=MakeAction(environsComplete, None))})
1404main.CompleteEnvirons('#all-environs', [])
1405
1406def doNothing(**ignored): pass
1407main.Append(BUILDERS = {'Dummy': Builder(action=MakeAction(doNothing, None))})
1408
1409# The final target to which all the original targets ultimately get attached.
1410main.Dummy('#all-targets', '#all-environs')
1411BUILD_TARGETS[:] = ['#all-targets']
1412
1413###################################################
1414#
1415# Define build environments for selected configurations.
1416#
1417###################################################
1418
1419def variant_name(path):
1420    return os.path.basename(path).lower().replace('_', '-')
1421main['variant_name'] = variant_name
1422main['VARIANT_NAME'] = '${variant_name(BUILDDIR)}'
1423
1424for variant_path in variant_paths:
1425    if not GetOption('silent'):
1426        print "Building in", variant_path
1427
1428    # Make a copy of the build-root environment to use for this config.
1429    env = main.Clone()
1430    env['BUILDDIR'] = variant_path
1431
1432    # variant_dir is the tail component of build path, and is used to
1433    # determine the build parameters (e.g., 'ALPHA_SE')
1434    (build_root, variant_dir) = splitpath(variant_path)
1435
1436    # Set env variables according to the build directory config.
1437    sticky_vars.files = []
1438    # Variables for $BUILD_ROOT/$VARIANT_DIR are stored in
1439    # $BUILD_ROOT/variables/$VARIANT_DIR so you can nuke
1440    # $BUILD_ROOT/$VARIANT_DIR without losing your variables settings.
1441    current_vars_file = joinpath(build_root, 'variables', variant_dir)
1442    if isfile(current_vars_file):
1443        sticky_vars.files.append(current_vars_file)
1444        if not GetOption('silent'):
1445            print "Using saved variables file %s" % current_vars_file
1446    else:
1447        # Build dir-specific variables file doesn't exist.
1448
1449        # Make sure the directory is there so we can create it later
1450        opt_dir = dirname(current_vars_file)
1451        if not isdir(opt_dir):
1452            mkdir(opt_dir)
1453
1454        # Get default build variables from source tree.  Variables are
1455        # normally determined by name of $VARIANT_DIR, but can be
1456        # overridden by '--default=' arg on command line.
1457        default = GetOption('default')
1458        opts_dir = joinpath(main.root.abspath, 'build_opts')
1459        if default:
1460            default_vars_files = [joinpath(build_root, 'variables', default),
1461                                  joinpath(opts_dir, default)]
1462        else:
1463            default_vars_files = [joinpath(opts_dir, variant_dir)]
1464        existing_files = filter(isfile, default_vars_files)
1465        if existing_files:
1466            default_vars_file = existing_files[0]
1467            sticky_vars.files.append(default_vars_file)
1468            print "Variables file %s not found,\n  using defaults in %s" \
1469                  % (current_vars_file, default_vars_file)
1470        else:
1471            print "Error: cannot find variables file %s or " \
1472                  "default file(s) %s" \
1473                  % (current_vars_file, ' or '.join(default_vars_files))
1474            Exit(1)
1475
1476    # Apply current variable settings to env
1477    sticky_vars.Update(env)
1478
1479    help_texts["local_vars"] += \
1480        "Build variables for %s:\n" % variant_dir \
1481                 + sticky_vars.GenerateHelpText(env)
1482
1483    # Process variable settings.
1484
1485    if not have_fenv and env['USE_FENV']:
1486        print "Warning: <fenv.h> not available; " \
1487              "forcing USE_FENV to False in", variant_dir + "."
1488        env['USE_FENV'] = False
1489
1490    if not env['USE_FENV']:
1491        print "Warning: No IEEE FP rounding mode control in", variant_dir + "."
1492        print "         FP results may deviate slightly from other platforms."
1493
1494    if env['EFENCE']:
1495        env.Append(LIBS=['efence'])
1496
1497    if env['USE_KVM']:
1498        if not have_kvm:
1499            print "Warning: Can not enable KVM, host seems to lack KVM support"
1500            env['USE_KVM'] = False
1501        elif not is_isa_kvm_compatible(env['TARGET_ISA']):
1502            print "Info: KVM support disabled due to unsupported host and " \
1503                "target ISA combination"
1504            env['USE_KVM'] = False
1505
1506    if env['BUILD_GPU']:
1507        env.Append(CPPDEFINES=['BUILD_GPU'])
1508
1509    # Warn about missing optional functionality
1510    if env['USE_KVM']:
1511        if not main['HAVE_PERF_ATTR_EXCLUDE_HOST']:
1512            print "Warning: perf_event headers lack support for the " \
1513                "exclude_host attribute. KVM instruction counts will " \
1514                "be inaccurate."
1515
1516    # Save sticky variable settings back to current variables file
1517    sticky_vars.Save(current_vars_file, env)
1518
1519    if env['USE_SSE2']:
1520        env.Append(CCFLAGS=['-msse2'])
1521
1522    # The src/SConscript file sets up the build rules in 'env' according
1523    # to the configured variables.  It returns a list of environments,
1524    # one for each variant build (debug, opt, etc.)
1525    SConscript('src/SConscript', variant_dir = variant_path, exports = 'env')
1526
1527def pairwise(iterable):
1528    "s -> (s0,s1), (s1,s2), (s2, s3), ..."
1529    a, b = itertools.tee(iterable)
1530    b.next()
1531    return itertools.izip(a, b)
1532
1533variant_names = [variant_name(path) for path in variant_paths]
1534
1535# Create false dependencies so SCons will parse ISAs, establish
1536# dependencies, and setup the build Environments serially. Either
1537# SCons (likely) and/or our SConscripts (possibly) cannot cope with -j
1538# greater than 1. It appears to be standard race condition stuff; it
1539# doesn't always fail, but usually, and the behaviors are different.
1540# Every time I tried to remove this, builds would fail in some
1541# creative new way. So, don't do that. You'll want to, though, because
1542# tests/SConscript takes a long time to make its Environments.
1543for t1, t2 in pairwise(sorted(variant_names)):
1544    main.Depends('#%s-deps'     % t2, '#%s-deps'     % t1)
1545    main.Depends('#%s-environs' % t2, '#%s-environs' % t1)
1546
1547# base help text
1548Help('''
1549Usage: scons [scons options] [build variables] [target(s)]
1550
1551Extra scons options:
1552%(options)s
1553
1554Global build variables:
1555%(global_vars)s
1556
1557%(local_vars)s
1558''' % help_texts)
1559