SConstruct revision 11497:bfed9fdf0ac7
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 = style_message % ("hg commit and qrefresh commands",
272                                           ".hg/hgrc file")
273git_style_message = style_message % ("'git commit'",
274                                     ".git/hooks/ directory")
275
276mercurial_style_upgrade_message = """
277Your Mercurial style hooks are not up-to-date. This script will now
278try to automatically update them. A backup of your hgrc will be saved
279in .hg/hgrc.old.
280Press enter to continue, or ctrl-c to abort: """
281
282mercurial_style_hook = """
283# The following lines were automatically added by gem5/SConstruct
284# to provide the gem5 style-checking hooks
285[extensions]
286hgstyle = %s/util/hgstyle.py
287
288[hooks]
289pretxncommit.style = python:hgstyle.check_style
290pre-qrefresh.style = python:hgstyle.check_style
291# End of SConstruct additions
292
293""" % (main.root.abspath)
294
295mercurial_lib_not_found = """
296Mercurial libraries cannot be found, ignoring style hook.  If
297you are a gem5 developer, please fix this and run the style
298hook. It is important.
299"""
300
301# Check for style hook and prompt for installation if it's not there.
302# Skip this if --ignore-style was specified, there's no interactive
303# terminal to prompt, or no recognized revision control system can be
304# found.
305ignore_style = GetOption('ignore_style') or not sys.stdin.isatty()
306
307# Try wire up Mercurial to the style hooks
308if not ignore_style and hgdir.exists():
309    style_hook = True
310    style_hooks = tuple()
311    hgrc = hgdir.File('hgrc')
312    hgrc_old = hgdir.File('hgrc.old')
313    try:
314        from mercurial import ui
315        ui = ui.ui()
316        ui.readconfig(hgrc.abspath)
317        style_hooks = (ui.config('hooks', 'pretxncommit.style', None),
318                       ui.config('hooks', 'pre-qrefresh.style', None))
319        style_hook = all(style_hooks)
320        style_extension = ui.config('extensions', 'style', None)
321    except ImportError:
322        print mercurial_lib_not_found
323
324    if "python:style.check_style" in style_hooks:
325        # Try to upgrade the style hooks
326        print mercurial_style_upgrade_message
327        # continue unless user does ctrl-c/ctrl-d etc.
328        try:
329            raw_input()
330        except:
331            print "Input exception, exiting scons.\n"
332            sys.exit(1)
333        shutil.copyfile(hgrc.abspath, hgrc_old.abspath)
334        re_style_hook = re.compile(r"^([^=#]+)\.style\s*=\s*([^#\s]+).*")
335        re_style_extension = re.compile("style\s*=\s*([^#\s]+).*")
336        old, new = open(hgrc_old.abspath, 'r'), open(hgrc.abspath, 'w')
337        for l in old:
338            m_hook = re_style_hook.match(l)
339            m_ext = re_style_extension.match(l)
340            if m_hook:
341                hook, check = m_hook.groups()
342                if check != "python:style.check_style":
343                    print "Warning: %s.style is using a non-default " \
344                        "checker: %s" % (hook, check)
345                if hook not in ("pretxncommit", "pre-qrefresh"):
346                    print "Warning: Updating unknown style hook: %s" % hook
347
348                l = "%s.style = python:hgstyle.check_style\n" % hook
349            elif m_ext and m_ext.group(1) == style_extension:
350                l = "hgstyle = %s/util/hgstyle.py\n" % main.root.abspath
351
352            new.write(l)
353    elif not style_hook:
354        print mercurial_style_message,
355        # continue unless user does ctrl-c/ctrl-d etc.
356        try:
357            raw_input()
358        except:
359            print "Input exception, exiting scons.\n"
360            sys.exit(1)
361        hgrc_path = '%s/.hg/hgrc' % main.root.abspath
362        print "Adding style hook to", hgrc_path, "\n"
363        try:
364            with open(hgrc_path, 'a') as f:
365                f.write(mercurial_style_hook)
366        except:
367            print "Error updating", hgrc_path
368            sys.exit(1)
369
370def install_git_style_hooks():
371    try:
372        gitdir = Dir(readCommand(
373            ["git", "rev-parse", "--git-dir"]).strip("\n"))
374    except Exception, e:
375        print "Warning: Failed to find git repo directory: %s" % e
376        return
377
378    git_hooks = gitdir.Dir("hooks")
379    git_pre_commit_hook = git_hooks.File("pre-commit")
380    git_style_script = File("util/git-pre-commit.py")
381
382    if git_pre_commit_hook.exists():
383        return
384
385    print git_style_message,
386    try:
387        raw_input()
388    except:
389        print "Input exception, exiting scons.\n"
390        sys.exit(1)
391
392    if not git_hooks.exists():
393        mkdir(git_hooks.get_abspath())
394
395    # Use a relative symlink if the hooks live in the source directory
396    if git_pre_commit_hook.is_under(main.root):
397        script_path = os.path.relpath(
398            git_style_script.get_abspath(),
399            git_pre_commit_hook.Dir(".").get_abspath())
400    else:
401        script_path = git_style_script.get_abspath()
402
403    try:
404        os.symlink(script_path, git_pre_commit_hook.get_abspath())
405    except:
406        print "Error updating git pre-commit hook"
407        raise
408
409# Try to wire up git to the style hooks
410if not ignore_style and main.root.Entry(".git").exists():
411    install_git_style_hooks()
412
413###################################################
414#
415# Figure out which configurations to set up based on the path(s) of
416# the target(s).
417#
418###################################################
419
420# Find default configuration & binary.
421Default(environ.get('M5_DEFAULT_BINARY', 'build/ALPHA/gem5.debug'))
422
423# helper function: find last occurrence of element in list
424def rfind(l, elt, offs = -1):
425    for i in range(len(l)+offs, 0, -1):
426        if l[i] == elt:
427            return i
428    raise ValueError, "element not found"
429
430# Take a list of paths (or SCons Nodes) and return a list with all
431# paths made absolute and ~-expanded.  Paths will be interpreted
432# relative to the launch directory unless a different root is provided
433def makePathListAbsolute(path_list, root=GetLaunchDir()):
434    return [abspath(joinpath(root, expanduser(str(p))))
435            for p in path_list]
436
437# Each target must have 'build' in the interior of the path; the
438# directory below this will determine the build parameters.  For
439# example, for target 'foo/bar/build/ALPHA_SE/arch/alpha/blah.do' we
440# recognize that ALPHA_SE specifies the configuration because it
441# follow 'build' in the build path.
442
443# The funky assignment to "[:]" is needed to replace the list contents
444# in place rather than reassign the symbol to a new list, which
445# doesn't work (obviously!).
446BUILD_TARGETS[:] = makePathListAbsolute(BUILD_TARGETS)
447
448# Generate a list of the unique build roots and configs that the
449# collected targets reference.
450variant_paths = []
451build_root = None
452for t in BUILD_TARGETS:
453    path_dirs = t.split('/')
454    try:
455        build_top = rfind(path_dirs, 'build', -2)
456    except:
457        print "Error: no non-leaf 'build' dir found on target path", t
458        Exit(1)
459    this_build_root = joinpath('/',*path_dirs[:build_top+1])
460    if not build_root:
461        build_root = this_build_root
462    else:
463        if this_build_root != build_root:
464            print "Error: build targets not under same build root\n"\
465                  "  %s\n  %s" % (build_root, this_build_root)
466            Exit(1)
467    variant_path = joinpath('/',*path_dirs[:build_top+2])
468    if variant_path not in variant_paths:
469        variant_paths.append(variant_path)
470
471# Make sure build_root exists (might not if this is the first build there)
472if not isdir(build_root):
473    mkdir(build_root)
474main['BUILDROOT'] = build_root
475
476Export('main')
477
478main.SConsignFile(joinpath(build_root, "sconsign"))
479
480# Default duplicate option is to use hard links, but this messes up
481# when you use emacs to edit a file in the target dir, as emacs moves
482# file to file~ then copies to file, breaking the link.  Symbolic
483# (soft) links work better.
484main.SetOption('duplicate', 'soft-copy')
485
486#
487# Set up global sticky variables... these are common to an entire build
488# tree (not specific to a particular build like ALPHA_SE)
489#
490
491global_vars_file = joinpath(build_root, 'variables.global')
492
493global_vars = Variables(global_vars_file, args=ARGUMENTS)
494
495global_vars.AddVariables(
496    ('CC', 'C compiler', environ.get('CC', main['CC'])),
497    ('CXX', 'C++ compiler', environ.get('CXX', main['CXX'])),
498    ('SWIG', 'SWIG tool', environ.get('SWIG', main['SWIG'])),
499    ('PROTOC', 'protoc tool', environ.get('PROTOC', 'protoc')),
500    ('BATCH', 'Use batch pool for build and tests', False),
501    ('BATCH_CMD', 'Batch pool submission command name', 'qdo'),
502    ('M5_BUILD_CACHE', 'Cache built objects in this directory', False),
503    ('EXTRAS', 'Add extra directories to the compilation', '')
504    )
505
506# Update main environment with values from ARGUMENTS & global_vars_file
507global_vars.Update(main)
508help_texts["global_vars"] += global_vars.GenerateHelpText(main)
509
510# Save sticky variable settings back to current variables file
511global_vars.Save(global_vars_file, main)
512
513# Parse EXTRAS variable to build list of all directories where we're
514# look for sources etc.  This list is exported as extras_dir_list.
515base_dir = main.srcdir.abspath
516if main['EXTRAS']:
517    extras_dir_list = makePathListAbsolute(main['EXTRAS'].split(':'))
518else:
519    extras_dir_list = []
520
521Export('base_dir')
522Export('extras_dir_list')
523
524# the ext directory should be on the #includes path
525main.Append(CPPPATH=[Dir('ext')])
526
527def strip_build_path(path, env):
528    path = str(path)
529    variant_base = env['BUILDROOT'] + os.path.sep
530    if path.startswith(variant_base):
531        path = path[len(variant_base):]
532    elif path.startswith('build/'):
533        path = path[6:]
534    return path
535
536# Generate a string of the form:
537#   common/path/prefix/src1, src2 -> tgt1, tgt2
538# to print while building.
539class Transform(object):
540    # all specific color settings should be here and nowhere else
541    tool_color = termcap.Normal
542    pfx_color = termcap.Yellow
543    srcs_color = termcap.Yellow + termcap.Bold
544    arrow_color = termcap.Blue + termcap.Bold
545    tgts_color = termcap.Yellow + termcap.Bold
546
547    def __init__(self, tool, max_sources=99):
548        self.format = self.tool_color + (" [%8s] " % tool) \
549                      + self.pfx_color + "%s" \
550                      + self.srcs_color + "%s" \
551                      + self.arrow_color + " -> " \
552                      + self.tgts_color + "%s" \
553                      + termcap.Normal
554        self.max_sources = max_sources
555
556    def __call__(self, target, source, env, for_signature=None):
557        # truncate source list according to max_sources param
558        source = source[0:self.max_sources]
559        def strip(f):
560            return strip_build_path(str(f), env)
561        if len(source) > 0:
562            srcs = map(strip, source)
563        else:
564            srcs = ['']
565        tgts = map(strip, target)
566        # surprisingly, os.path.commonprefix is a dumb char-by-char string
567        # operation that has nothing to do with paths.
568        com_pfx = os.path.commonprefix(srcs + tgts)
569        com_pfx_len = len(com_pfx)
570        if com_pfx:
571            # do some cleanup and sanity checking on common prefix
572            if com_pfx[-1] == ".":
573                # prefix matches all but file extension: ok
574                # back up one to change 'foo.cc -> o' to 'foo.cc -> .o'
575                com_pfx = com_pfx[0:-1]
576            elif com_pfx[-1] == "/":
577                # common prefix is directory path: OK
578                pass
579            else:
580                src0_len = len(srcs[0])
581                tgt0_len = len(tgts[0])
582                if src0_len == com_pfx_len:
583                    # source is a substring of target, OK
584                    pass
585                elif tgt0_len == com_pfx_len:
586                    # target is a substring of source, need to back up to
587                    # avoid empty string on RHS of arrow
588                    sep_idx = com_pfx.rfind(".")
589                    if sep_idx != -1:
590                        com_pfx = com_pfx[0:sep_idx]
591                    else:
592                        com_pfx = ''
593                elif src0_len > com_pfx_len and srcs[0][com_pfx_len] == ".":
594                    # still splitting at file extension: ok
595                    pass
596                else:
597                    # probably a fluke; ignore it
598                    com_pfx = ''
599        # recalculate length in case com_pfx was modified
600        com_pfx_len = len(com_pfx)
601        def fmt(files):
602            f = map(lambda s: s[com_pfx_len:], files)
603            return ', '.join(f)
604        return self.format % (com_pfx, fmt(srcs), fmt(tgts))
605
606Export('Transform')
607
608# enable the regression script to use the termcap
609main['TERMCAP'] = termcap
610
611if GetOption('verbose'):
612    def MakeAction(action, string, *args, **kwargs):
613        return Action(action, *args, **kwargs)
614else:
615    MakeAction = Action
616    main['CCCOMSTR']        = Transform("CC")
617    main['CXXCOMSTR']       = Transform("CXX")
618    main['ASCOMSTR']        = Transform("AS")
619    main['SWIGCOMSTR']      = Transform("SWIG")
620    main['ARCOMSTR']        = Transform("AR", 0)
621    main['LINKCOMSTR']      = Transform("LINK", 0)
622    main['RANLIBCOMSTR']    = Transform("RANLIB", 0)
623    main['M4COMSTR']        = Transform("M4")
624    main['SHCCCOMSTR']      = Transform("SHCC")
625    main['SHCXXCOMSTR']     = Transform("SHCXX")
626Export('MakeAction')
627
628# Initialize the Link-Time Optimization (LTO) flags
629main['LTO_CCFLAGS'] = []
630main['LTO_LDFLAGS'] = []
631
632# According to the readme, tcmalloc works best if the compiler doesn't
633# assume that we're using the builtin malloc and friends. These flags
634# are compiler-specific, so we need to set them after we detect which
635# compiler we're using.
636main['TCMALLOC_CCFLAGS'] = []
637
638CXX_version = readCommand([main['CXX'],'--version'], exception=False)
639CXX_V = readCommand([main['CXX'],'-V'], exception=False)
640
641main['GCC'] = CXX_version and CXX_version.find('g++') >= 0
642main['CLANG'] = CXX_version and CXX_version.find('clang') >= 0
643if main['GCC'] + main['CLANG'] > 1:
644    print 'Error: How can we have two at the same time?'
645    Exit(1)
646
647# Set up default C++ compiler flags
648if main['GCC'] or main['CLANG']:
649    # As gcc and clang share many flags, do the common parts here
650    main.Append(CCFLAGS=['-pipe'])
651    main.Append(CCFLAGS=['-fno-strict-aliasing'])
652    # Enable -Wall and -Wextra and then disable the few warnings that
653    # we consistently violate
654    main.Append(CCFLAGS=['-Wall', '-Wundef', '-Wextra',
655                         '-Wno-sign-compare', '-Wno-unused-parameter'])
656    # We always compile using C++11
657    main.Append(CXXFLAGS=['-std=c++11'])
658else:
659    print termcap.Yellow + termcap.Bold + 'Error' + termcap.Normal,
660    print "Don't know what compiler options to use for your compiler."
661    print termcap.Yellow + '       compiler:' + termcap.Normal, main['CXX']
662    print termcap.Yellow + '       version:' + termcap.Normal,
663    if not CXX_version:
664        print termcap.Yellow + termcap.Bold + "COMMAND NOT FOUND!" +\
665               termcap.Normal
666    else:
667        print CXX_version.replace('\n', '<nl>')
668    print "       If you're trying to use a compiler other than GCC"
669    print "       or clang, there appears to be something wrong with your"
670    print "       environment."
671    print "       "
672    print "       If you are trying to use a compiler other than those listed"
673    print "       above you will need to ease fix SConstruct and "
674    print "       src/SConscript to support that compiler."
675    Exit(1)
676
677if main['GCC']:
678    # Check for a supported version of gcc. >= 4.7 is chosen for its
679    # level of c++11 support. See
680    # http://gcc.gnu.org/projects/cxx0x.html for details.
681    gcc_version = readCommand([main['CXX'], '-dumpversion'], exception=False)
682    if compareVersions(gcc_version, "4.7") < 0:
683        print 'Error: gcc version 4.7 or newer required.'
684        print '       Installed version:', gcc_version
685        Exit(1)
686
687    main['GCC_VERSION'] = gcc_version
688
689    # gcc from version 4.8 and above generates "rep; ret" instructions
690    # to avoid performance penalties on certain AMD chips. Older
691    # assemblers detect this as an error, "Error: expecting string
692    # instruction after `rep'"
693    if compareVersions(gcc_version, "4.8") > 0:
694        as_version_raw = readCommand([main['AS'], '-v', '/dev/null'],
695                                     exception=False).split()
696
697        # version strings may contain extra distro-specific
698        # qualifiers, so play it safe and keep only what comes before
699        # the first hyphen
700        as_version = as_version_raw[-1].split('-')[0] if as_version_raw \
701            else None
702
703        if not as_version or compareVersions(as_version, "2.23") < 0:
704            print termcap.Yellow + termcap.Bold + \
705                'Warning: This combination of gcc and binutils have' + \
706                ' known incompatibilities.\n' + \
707                '         If you encounter build problems, please update ' + \
708                'binutils to 2.23.' + \
709                termcap.Normal
710
711    # Make sure we warn if the user has requested to compile with the
712    # Undefined Benahvior Sanitizer and this version of gcc does not
713    # support it.
714    if GetOption('with_ubsan') and \
715            compareVersions(gcc_version, '4.9') < 0:
716        print termcap.Yellow + termcap.Bold + \
717            'Warning: UBSan is only supported using gcc 4.9 and later.' + \
718            termcap.Normal
719
720    # Add the appropriate Link-Time Optimization (LTO) flags
721    # unless LTO is explicitly turned off. Note that these flags
722    # are only used by the fast target.
723    if not GetOption('no_lto'):
724        # Pass the LTO flag when compiling to produce GIMPLE
725        # output, we merely create the flags here and only append
726        # them later
727        main['LTO_CCFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
728
729        # Use the same amount of jobs for LTO as we are running
730        # scons with
731        main['LTO_LDFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
732
733    main.Append(TCMALLOC_CCFLAGS=['-fno-builtin-malloc', '-fno-builtin-calloc',
734                                  '-fno-builtin-realloc', '-fno-builtin-free'])
735
736    # add option to check for undeclared overrides
737    if compareVersions(gcc_version, "5.0") > 0:
738        main.Append(CCFLAGS=['-Wno-error=suggest-override'])
739
740elif main['CLANG']:
741    # Check for a supported version of clang, >= 3.1 is needed to
742    # support similar features as gcc 4.7. See
743    # http://clang.llvm.org/cxx_status.html for details
744    clang_version_re = re.compile(".* version (\d+\.\d+)")
745    clang_version_match = clang_version_re.search(CXX_version)
746    if (clang_version_match):
747        clang_version = clang_version_match.groups()[0]
748        if compareVersions(clang_version, "3.1") < 0:
749            print 'Error: clang version 3.1 or newer required.'
750            print '       Installed version:', clang_version
751            Exit(1)
752    else:
753        print 'Error: Unable to determine clang version.'
754        Exit(1)
755
756    # clang has a few additional warnings that we disable, extraneous
757    # parantheses are allowed due to Ruby's printing of the AST,
758    # finally self assignments are allowed as the generated CPU code
759    # is relying on this
760    main.Append(CCFLAGS=['-Wno-parentheses',
761                         '-Wno-self-assign',
762                         # Some versions of libstdc++ (4.8?) seem to
763                         # use struct hash and class hash
764                         # interchangeably.
765                         '-Wno-mismatched-tags',
766                         ])
767
768    main.Append(TCMALLOC_CCFLAGS=['-fno-builtin'])
769
770    # On Mac OS X/Darwin we need to also use libc++ (part of XCode) as
771    # opposed to libstdc++, as the later is dated.
772    if sys.platform == "darwin":
773        main.Append(CXXFLAGS=['-stdlib=libc++'])
774        main.Append(LIBS=['c++'])
775
776else:
777    print termcap.Yellow + termcap.Bold + 'Error' + termcap.Normal,
778    print "Don't know what compiler options to use for your compiler."
779    print termcap.Yellow + '       compiler:' + termcap.Normal, main['CXX']
780    print termcap.Yellow + '       version:' + termcap.Normal,
781    if not CXX_version:
782        print termcap.Yellow + termcap.Bold + "COMMAND NOT FOUND!" +\
783               termcap.Normal
784    else:
785        print CXX_version.replace('\n', '<nl>')
786    print "       If you're trying to use a compiler other than GCC"
787    print "       or clang, there appears to be something wrong with your"
788    print "       environment."
789    print "       "
790    print "       If you are trying to use a compiler other than those listed"
791    print "       above you will need to ease fix SConstruct and "
792    print "       src/SConscript to support that compiler."
793    Exit(1)
794
795# Set up common yacc/bison flags (needed for Ruby)
796main['YACCFLAGS'] = '-d'
797main['YACCHXXFILESUFFIX'] = '.hh'
798
799# Do this after we save setting back, or else we'll tack on an
800# extra 'qdo' every time we run scons.
801if main['BATCH']:
802    main['CC']     = main['BATCH_CMD'] + ' ' + main['CC']
803    main['CXX']    = main['BATCH_CMD'] + ' ' + main['CXX']
804    main['AS']     = main['BATCH_CMD'] + ' ' + main['AS']
805    main['AR']     = main['BATCH_CMD'] + ' ' + main['AR']
806    main['RANLIB'] = main['BATCH_CMD'] + ' ' + main['RANLIB']
807
808if sys.platform == 'cygwin':
809    # cygwin has some header file issues...
810    main.Append(CCFLAGS=["-Wno-uninitialized"])
811
812# Check for the protobuf compiler
813protoc_version = readCommand([main['PROTOC'], '--version'],
814                             exception='').split()
815
816# First two words should be "libprotoc x.y.z"
817if len(protoc_version) < 2 or protoc_version[0] != 'libprotoc':
818    print termcap.Yellow + termcap.Bold + \
819        'Warning: Protocol buffer compiler (protoc) not found.\n' + \
820        '         Please install protobuf-compiler for tracing support.' + \
821        termcap.Normal
822    main['PROTOC'] = False
823else:
824    # Based on the availability of the compress stream wrappers,
825    # require 2.1.0
826    min_protoc_version = '2.1.0'
827    if compareVersions(protoc_version[1], min_protoc_version) < 0:
828        print termcap.Yellow + termcap.Bold + \
829            'Warning: protoc version', min_protoc_version, \
830            'or newer required.\n' + \
831            '         Installed version:', protoc_version[1], \
832            termcap.Normal
833        main['PROTOC'] = False
834    else:
835        # Attempt to determine the appropriate include path and
836        # library path using pkg-config, that means we also need to
837        # check for pkg-config. Note that it is possible to use
838        # protobuf without the involvement of pkg-config. Later on we
839        # check go a library config check and at that point the test
840        # will fail if libprotobuf cannot be found.
841        if readCommand(['pkg-config', '--version'], exception=''):
842            try:
843                # Attempt to establish what linking flags to add for protobuf
844                # using pkg-config
845                main.ParseConfig('pkg-config --cflags --libs-only-L protobuf')
846            except:
847                print termcap.Yellow + termcap.Bold + \
848                    'Warning: pkg-config could not get protobuf flags.' + \
849                    termcap.Normal
850
851# Check for SWIG
852if not main.has_key('SWIG'):
853    print 'Error: SWIG utility not found.'
854    print '       Please install (see http://www.swig.org) and retry.'
855    Exit(1)
856
857# Check for appropriate SWIG version
858swig_version = readCommand([main['SWIG'], '-version'], exception='').split()
859# First 3 words should be "SWIG Version x.y.z"
860if len(swig_version) < 3 or \
861        swig_version[0] != 'SWIG' or swig_version[1] != 'Version':
862    print 'Error determining SWIG version.'
863    Exit(1)
864
865min_swig_version = '2.0.4'
866if compareVersions(swig_version[2], min_swig_version) < 0:
867    print 'Error: SWIG version', min_swig_version, 'or newer required.'
868    print '       Installed version:', swig_version[2]
869    Exit(1)
870
871# Check for known incompatibilities. The standard library shipped with
872# gcc >= 4.9 does not play well with swig versions prior to 3.0
873if main['GCC'] and compareVersions(gcc_version, '4.9') >= 0 and \
874        compareVersions(swig_version[2], '3.0') < 0:
875    print termcap.Yellow + termcap.Bold + \
876        'Warning: This combination of gcc and swig have' + \
877        ' known incompatibilities.\n' + \
878        '         If you encounter build problems, please update ' + \
879        'swig to 3.0 or later.' + \
880        termcap.Normal
881
882# Set up SWIG flags & scanner
883swig_flags=Split('-c++ -python -modern -templatereduce $_CPPINCFLAGS')
884main.Append(SWIGFLAGS=swig_flags)
885
886# Check for 'timeout' from GNU coreutils. If present, regressions will
887# be run with a time limit. We require version 8.13 since we rely on
888# support for the '--foreground' option.
889timeout_lines = readCommand(['timeout', '--version'],
890                            exception='').splitlines()
891# Get the first line and tokenize it
892timeout_version = timeout_lines[0].split() if timeout_lines else []
893main['TIMEOUT'] =  timeout_version and \
894    compareVersions(timeout_version[-1], '8.13') >= 0
895
896# filter out all existing swig scanners, they mess up the dependency
897# stuff for some reason
898scanners = []
899for scanner in main['SCANNERS']:
900    skeys = scanner.skeys
901    if skeys == '.i':
902        continue
903
904    if isinstance(skeys, (list, tuple)) and '.i' in skeys:
905        continue
906
907    scanners.append(scanner)
908
909# add the new swig scanner that we like better
910from SCons.Scanner import ClassicCPP as CPPScanner
911swig_inc_re = '^[ \t]*[%,#][ \t]*(?:include|import)[ \t]*(<|")([^>"]+)(>|")'
912scanners.append(CPPScanner("SwigScan", [ ".i" ], "CPPPATH", swig_inc_re))
913
914# replace the scanners list that has what we want
915main['SCANNERS'] = scanners
916
917# Add a custom Check function to test for structure members.
918def CheckMember(context, include, decl, member, include_quotes="<>"):
919    context.Message("Checking for member %s in %s..." %
920                    (member, decl))
921    text = """
922#include %(header)s
923int main(){
924  %(decl)s test;
925  (void)test.%(member)s;
926  return 0;
927};
928""" % { "header" : include_quotes[0] + include + include_quotes[1],
929        "decl" : decl,
930        "member" : member,
931        }
932
933    ret = context.TryCompile(text, extension=".cc")
934    context.Result(ret)
935    return ret
936
937# Platform-specific configuration.  Note again that we assume that all
938# builds under a given build root run on the same host platform.
939conf = Configure(main,
940                 conf_dir = joinpath(build_root, '.scons_config'),
941                 log_file = joinpath(build_root, 'scons_config.log'),
942                 custom_tests = {
943        'CheckMember' : CheckMember,
944        })
945
946# Check if we should compile a 64 bit binary on Mac OS X/Darwin
947try:
948    import platform
949    uname = platform.uname()
950    if uname[0] == 'Darwin' and compareVersions(uname[2], '9.0.0') >= 0:
951        if int(readCommand('sysctl -n hw.cpu64bit_capable')[0]):
952            main.Append(CCFLAGS=['-arch', 'x86_64'])
953            main.Append(CFLAGS=['-arch', 'x86_64'])
954            main.Append(LINKFLAGS=['-arch', 'x86_64'])
955            main.Append(ASFLAGS=['-arch', 'x86_64'])
956except:
957    pass
958
959# Recent versions of scons substitute a "Null" object for Configure()
960# when configuration isn't necessary, e.g., if the "--help" option is
961# present.  Unfortuantely this Null object always returns false,
962# breaking all our configuration checks.  We replace it with our own
963# more optimistic null object that returns True instead.
964if not conf:
965    def NullCheck(*args, **kwargs):
966        return True
967
968    class NullConf:
969        def __init__(self, env):
970            self.env = env
971        def Finish(self):
972            return self.env
973        def __getattr__(self, mname):
974            return NullCheck
975
976    conf = NullConf(main)
977
978# Cache build files in the supplied directory.
979if main['M5_BUILD_CACHE']:
980    print 'Using build cache located at', main['M5_BUILD_CACHE']
981    CacheDir(main['M5_BUILD_CACHE'])
982
983if not GetOption('without_python'):
984    # Find Python include and library directories for embedding the
985    # interpreter. We rely on python-config to resolve the appropriate
986    # includes and linker flags. ParseConfig does not seem to understand
987    # the more exotic linker flags such as -Xlinker and -export-dynamic so
988    # we add them explicitly below. If you want to link in an alternate
989    # version of python, see above for instructions on how to invoke
990    # scons with the appropriate PATH set.
991    #
992    # First we check if python2-config exists, else we use python-config
993    python_config = readCommand(['which', 'python2-config'],
994                                exception='').strip()
995    if not os.path.exists(python_config):
996        python_config = readCommand(['which', 'python-config'],
997                                    exception='').strip()
998    py_includes = readCommand([python_config, '--includes'],
999                              exception='').split()
1000    # Strip the -I from the include folders before adding them to the
1001    # CPPPATH
1002    main.Append(CPPPATH=map(lambda inc: inc[2:], py_includes))
1003
1004    # Read the linker flags and split them into libraries and other link
1005    # flags. The libraries are added later through the call the CheckLib.
1006    py_ld_flags = readCommand([python_config, '--ldflags'],
1007        exception='').split()
1008    py_libs = []
1009    for lib in py_ld_flags:
1010         if not lib.startswith('-l'):
1011             main.Append(LINKFLAGS=[lib])
1012         else:
1013             lib = lib[2:]
1014             if lib not in py_libs:
1015                 py_libs.append(lib)
1016
1017    # verify that this stuff works
1018    if not conf.CheckHeader('Python.h', '<>'):
1019        print "Error: can't find Python.h header in", py_includes
1020        print "Install Python headers (package python-dev on Ubuntu and RedHat)"
1021        Exit(1)
1022
1023    for lib in py_libs:
1024        if not conf.CheckLib(lib):
1025            print "Error: can't find library %s required by python" % lib
1026            Exit(1)
1027
1028# On Solaris you need to use libsocket for socket ops
1029if not conf.CheckLibWithHeader(None, 'sys/socket.h', 'C++', 'accept(0,0,0);'):
1030   if not conf.CheckLibWithHeader('socket', 'sys/socket.h', 'C++', 'accept(0,0,0);'):
1031       print "Can't find library with socket calls (e.g. accept())"
1032       Exit(1)
1033
1034# Check for zlib.  If the check passes, libz will be automatically
1035# added to the LIBS environment variable.
1036if not conf.CheckLibWithHeader('z', 'zlib.h', 'C++','zlibVersion();'):
1037    print 'Error: did not find needed zlib compression library '\
1038          'and/or zlib.h header file.'
1039    print '       Please install zlib and try again.'
1040    Exit(1)
1041
1042# If we have the protobuf compiler, also make sure we have the
1043# development libraries. If the check passes, libprotobuf will be
1044# automatically added to the LIBS environment variable. After
1045# this, we can use the HAVE_PROTOBUF flag to determine if we have
1046# got both protoc and libprotobuf available.
1047main['HAVE_PROTOBUF'] = main['PROTOC'] and \
1048    conf.CheckLibWithHeader('protobuf', 'google/protobuf/message.h',
1049                            'C++', 'GOOGLE_PROTOBUF_VERIFY_VERSION;')
1050
1051# If we have the compiler but not the library, print another warning.
1052if main['PROTOC'] and not main['HAVE_PROTOBUF']:
1053    print termcap.Yellow + termcap.Bold + \
1054        'Warning: did not find protocol buffer library and/or headers.\n' + \
1055    '       Please install libprotobuf-dev for tracing support.' + \
1056    termcap.Normal
1057
1058# Check for librt.
1059have_posix_clock = \
1060    conf.CheckLibWithHeader(None, 'time.h', 'C',
1061                            'clock_nanosleep(0,0,NULL,NULL);') or \
1062    conf.CheckLibWithHeader('rt', 'time.h', 'C',
1063                            'clock_nanosleep(0,0,NULL,NULL);')
1064
1065have_posix_timers = \
1066    conf.CheckLibWithHeader([None, 'rt'], [ 'time.h', 'signal.h' ], 'C',
1067                            'timer_create(CLOCK_MONOTONIC, NULL, NULL);')
1068
1069if not GetOption('without_tcmalloc'):
1070    if conf.CheckLib('tcmalloc'):
1071        main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
1072    elif conf.CheckLib('tcmalloc_minimal'):
1073        main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
1074    else:
1075        print termcap.Yellow + termcap.Bold + \
1076              "You can get a 12% performance improvement by "\
1077              "installing tcmalloc (libgoogle-perftools-dev package "\
1078              "on Ubuntu or RedHat)." + termcap.Normal
1079
1080
1081# Detect back trace implementations. The last implementation in the
1082# list will be used by default.
1083backtrace_impls = [ "none" ]
1084
1085if conf.CheckLibWithHeader(None, 'execinfo.h', 'C',
1086                           'backtrace_symbols_fd((void*)0, 0, 0);'):
1087    backtrace_impls.append("glibc")
1088
1089if backtrace_impls[-1] == "none":
1090    default_backtrace_impl = "none"
1091    print termcap.Yellow + termcap.Bold + \
1092        "No suitable back trace implementation found." + \
1093        termcap.Normal
1094
1095if not have_posix_clock:
1096    print "Can't find library for POSIX clocks."
1097
1098# Check for <fenv.h> (C99 FP environment control)
1099have_fenv = conf.CheckHeader('fenv.h', '<>')
1100if not have_fenv:
1101    print "Warning: Header file <fenv.h> not found."
1102    print "         This host has no IEEE FP rounding mode control."
1103
1104# Check if we should enable KVM-based hardware virtualization. The API
1105# we rely on exists since version 2.6.36 of the kernel, but somehow
1106# the KVM_API_VERSION does not reflect the change. We test for one of
1107# the types as a fall back.
1108have_kvm = conf.CheckHeader('linux/kvm.h', '<>')
1109if not have_kvm:
1110    print "Info: Compatible header file <linux/kvm.h> not found, " \
1111        "disabling KVM support."
1112
1113# x86 needs support for xsave. We test for the structure here since we
1114# won't be able to run new tests by the time we know which ISA we're
1115# targeting.
1116have_kvm_xsave = conf.CheckTypeSize('struct kvm_xsave',
1117                                    '#include <linux/kvm.h>') != 0
1118
1119# Check if the requested target ISA is compatible with the host
1120def is_isa_kvm_compatible(isa):
1121    try:
1122        import platform
1123        host_isa = platform.machine()
1124    except:
1125        print "Warning: Failed to determine host ISA."
1126        return False
1127
1128    if not have_posix_timers:
1129        print "Warning: Can not enable KVM, host seems to lack support " \
1130            "for POSIX timers"
1131        return False
1132
1133    if isa == "arm":
1134        return host_isa in ( "armv7l", "aarch64" )
1135    elif isa == "x86":
1136        if host_isa != "x86_64":
1137            return False
1138
1139        if not have_kvm_xsave:
1140            print "KVM on x86 requires xsave support in kernel headers."
1141            return False
1142
1143        return True
1144    else:
1145        return False
1146
1147
1148# Check if the exclude_host attribute is available. We want this to
1149# get accurate instruction counts in KVM.
1150main['HAVE_PERF_ATTR_EXCLUDE_HOST'] = conf.CheckMember(
1151    'linux/perf_event.h', 'struct perf_event_attr', 'exclude_host')
1152
1153
1154######################################################################
1155#
1156# Finish the configuration
1157#
1158main = conf.Finish()
1159
1160######################################################################
1161#
1162# Collect all non-global variables
1163#
1164
1165# Define the universe of supported ISAs
1166all_isa_list = [ ]
1167all_gpu_isa_list = [ ]
1168Export('all_isa_list')
1169Export('all_gpu_isa_list')
1170
1171class CpuModel(object):
1172    '''The CpuModel class encapsulates everything the ISA parser needs to
1173    know about a particular CPU model.'''
1174
1175    # Dict of available CPU model objects.  Accessible as CpuModel.dict.
1176    dict = {}
1177
1178    # Constructor.  Automatically adds models to CpuModel.dict.
1179    def __init__(self, name, default=False):
1180        self.name = name           # name of model
1181
1182        # This cpu is enabled by default
1183        self.default = default
1184
1185        # Add self to dict
1186        if name in CpuModel.dict:
1187            raise AttributeError, "CpuModel '%s' already registered" % name
1188        CpuModel.dict[name] = self
1189
1190Export('CpuModel')
1191
1192# Sticky variables get saved in the variables file so they persist from
1193# one invocation to the next (unless overridden, in which case the new
1194# value becomes sticky).
1195sticky_vars = Variables(args=ARGUMENTS)
1196Export('sticky_vars')
1197
1198# Sticky variables that should be exported
1199export_vars = []
1200Export('export_vars')
1201
1202# For Ruby
1203all_protocols = []
1204Export('all_protocols')
1205protocol_dirs = []
1206Export('protocol_dirs')
1207slicc_includes = []
1208Export('slicc_includes')
1209
1210# Walk the tree and execute all SConsopts scripts that wil add to the
1211# above variables
1212if GetOption('verbose'):
1213    print "Reading SConsopts"
1214for bdir in [ base_dir ] + extras_dir_list:
1215    if not isdir(bdir):
1216        print "Error: directory '%s' does not exist" % bdir
1217        Exit(1)
1218    for root, dirs, files in os.walk(bdir):
1219        if 'SConsopts' in files:
1220            if GetOption('verbose'):
1221                print "Reading", joinpath(root, 'SConsopts')
1222            SConscript(joinpath(root, 'SConsopts'))
1223
1224all_isa_list.sort()
1225all_gpu_isa_list.sort()
1226
1227sticky_vars.AddVariables(
1228    EnumVariable('TARGET_ISA', 'Target ISA', 'alpha', all_isa_list),
1229    EnumVariable('TARGET_GPU_ISA', 'Target GPU ISA', 'hsail', all_gpu_isa_list),
1230    ListVariable('CPU_MODELS', 'CPU models',
1231                 sorted(n for n,m in CpuModel.dict.iteritems() if m.default),
1232                 sorted(CpuModel.dict.keys())),
1233    BoolVariable('EFENCE', 'Link with Electric Fence malloc debugger',
1234                 False),
1235    BoolVariable('SS_COMPATIBLE_FP',
1236                 'Make floating-point results compatible with SimpleScalar',
1237                 False),
1238    BoolVariable('USE_SSE2',
1239                 'Compile for SSE2 (-msse2) to get IEEE FP on x86 hosts',
1240                 False),
1241    BoolVariable('USE_POSIX_CLOCK', 'Use POSIX Clocks', have_posix_clock),
1242    BoolVariable('USE_FENV', 'Use <fenv.h> IEEE mode control', have_fenv),
1243    BoolVariable('CP_ANNOTATE', 'Enable critical path annotation capability', False),
1244    BoolVariable('USE_KVM', 'Enable hardware virtualized (KVM) CPU models', have_kvm),
1245    BoolVariable('BUILD_GPU', 'Build the compute-GPU model', False),
1246    EnumVariable('PROTOCOL', 'Coherence protocol for Ruby', 'None',
1247                  all_protocols),
1248    EnumVariable('BACKTRACE_IMPL', 'Post-mortem dump implementation',
1249                 backtrace_impls[-1], backtrace_impls)
1250    )
1251
1252# These variables get exported to #defines in config/*.hh (see src/SConscript).
1253export_vars += ['USE_FENV', 'SS_COMPATIBLE_FP', 'TARGET_ISA', 'TARGET_GPU_ISA',
1254                'CP_ANNOTATE', 'USE_POSIX_CLOCK', 'USE_KVM', 'PROTOCOL',
1255                'HAVE_PROTOBUF', 'HAVE_PERF_ATTR_EXCLUDE_HOST']
1256
1257###################################################
1258#
1259# Define a SCons builder for configuration flag headers.
1260#
1261###################################################
1262
1263# This function generates a config header file that #defines the
1264# variable symbol to the current variable setting (0 or 1).  The source
1265# operands are the name of the variable and a Value node containing the
1266# value of the variable.
1267def build_config_file(target, source, env):
1268    (variable, value) = [s.get_contents() for s in source]
1269    f = file(str(target[0]), 'w')
1270    print >> f, '#define', variable, value
1271    f.close()
1272    return None
1273
1274# Combine the two functions into a scons Action object.
1275config_action = MakeAction(build_config_file, Transform("CONFIG H", 2))
1276
1277# The emitter munges the source & target node lists to reflect what
1278# we're really doing.
1279def config_emitter(target, source, env):
1280    # extract variable name from Builder arg
1281    variable = str(target[0])
1282    # True target is config header file
1283    target = joinpath('config', variable.lower() + '.hh')
1284    val = env[variable]
1285    if isinstance(val, bool):
1286        # Force value to 0/1
1287        val = int(val)
1288    elif isinstance(val, str):
1289        val = '"' + val + '"'
1290
1291    # Sources are variable name & value (packaged in SCons Value nodes)
1292    return ([target], [Value(variable), Value(val)])
1293
1294config_builder = Builder(emitter = config_emitter, action = config_action)
1295
1296main.Append(BUILDERS = { 'ConfigFile' : config_builder })
1297
1298# libelf build is shared across all configs in the build root.
1299main.SConscript('ext/libelf/SConscript',
1300                variant_dir = joinpath(build_root, 'libelf'))
1301
1302# iostream3 build is shared across all configs in the build root.
1303main.SConscript('ext/iostream3/SConscript',
1304                variant_dir = joinpath(build_root, 'iostream3'))
1305
1306# libfdt build is shared across all configs in the build root.
1307main.SConscript('ext/libfdt/SConscript',
1308                variant_dir = joinpath(build_root, 'libfdt'))
1309
1310# fputils build is shared across all configs in the build root.
1311main.SConscript('ext/fputils/SConscript',
1312                variant_dir = joinpath(build_root, 'fputils'))
1313
1314# DRAMSim2 build is shared across all configs in the build root.
1315main.SConscript('ext/dramsim2/SConscript',
1316                variant_dir = joinpath(build_root, 'dramsim2'))
1317
1318# DRAMPower build is shared across all configs in the build root.
1319main.SConscript('ext/drampower/SConscript',
1320                variant_dir = joinpath(build_root, 'drampower'))
1321
1322# nomali build is shared across all configs in the build root.
1323main.SConscript('ext/nomali/SConscript',
1324                variant_dir = joinpath(build_root, 'nomali'))
1325
1326###################################################
1327#
1328# This function is used to set up a directory with switching headers
1329#
1330###################################################
1331
1332main['ALL_ISA_LIST'] = all_isa_list
1333main['ALL_GPU_ISA_LIST'] = all_gpu_isa_list
1334all_isa_deps = {}
1335def make_switching_dir(dname, switch_headers, env):
1336    # Generate the header.  target[0] is the full path of the output
1337    # header to generate.  'source' is a dummy variable, since we get the
1338    # list of ISAs from env['ALL_ISA_LIST'].
1339    def gen_switch_hdr(target, source, env):
1340        fname = str(target[0])
1341        isa = env['TARGET_ISA'].lower()
1342        try:
1343            f = open(fname, 'w')
1344            print >>f, '#include "%s/%s/%s"' % (dname, isa, basename(fname))
1345            f.close()
1346        except IOError:
1347            print "Failed to create %s" % fname
1348            raise
1349
1350    # Build SCons Action object. 'varlist' specifies env vars that this
1351    # action depends on; when env['ALL_ISA_LIST'] changes these actions
1352    # should get re-executed.
1353    switch_hdr_action = MakeAction(gen_switch_hdr,
1354                          Transform("GENERATE"), varlist=['ALL_ISA_LIST'])
1355
1356    # Instantiate actions for each header
1357    for hdr in switch_headers:
1358        env.Command(hdr, [], switch_hdr_action)
1359
1360    isa_target = Dir('.').up().name.lower().replace('_', '-')
1361    env['PHONY_BASE'] = '#'+isa_target
1362    all_isa_deps[isa_target] = None
1363
1364Export('make_switching_dir')
1365
1366def make_gpu_switching_dir(dname, switch_headers, env):
1367    # Generate the header.  target[0] is the full path of the output
1368    # header to generate.  'source' is a dummy variable, since we get the
1369    # list of ISAs from env['ALL_ISA_LIST'].
1370    def gen_switch_hdr(target, source, env):
1371        fname = str(target[0])
1372
1373        isa = env['TARGET_GPU_ISA'].lower()
1374
1375        try:
1376            f = open(fname, 'w')
1377            print >>f, '#include "%s/%s/%s"' % (dname, isa, basename(fname))
1378            f.close()
1379        except IOError:
1380            print "Failed to create %s" % fname
1381            raise
1382
1383    # Build SCons Action object. 'varlist' specifies env vars that this
1384    # action depends on; when env['ALL_ISA_LIST'] changes these actions
1385    # should get re-executed.
1386    switch_hdr_action = MakeAction(gen_switch_hdr,
1387                          Transform("GENERATE"), varlist=['ALL_ISA_GPU_LIST'])
1388
1389    # Instantiate actions for each header
1390    for hdr in switch_headers:
1391        env.Command(hdr, [], switch_hdr_action)
1392
1393Export('make_gpu_switching_dir')
1394
1395# all-isas -> all-deps -> all-environs -> all_targets
1396main.Alias('#all-isas', [])
1397main.Alias('#all-deps', '#all-isas')
1398
1399# Dummy target to ensure all environments are created before telling
1400# SCons what to actually make (the command line arguments).  We attach
1401# them to the dependence graph after the environments are complete.
1402ORIG_BUILD_TARGETS = list(BUILD_TARGETS) # force a copy; gets closure to work.
1403def environsComplete(target, source, env):
1404    for t in ORIG_BUILD_TARGETS:
1405        main.Depends('#all-targets', t)
1406
1407# Each build/* switching_dir attaches its *-environs target to #all-environs.
1408main.Append(BUILDERS = {'CompleteEnvirons' :
1409                        Builder(action=MakeAction(environsComplete, None))})
1410main.CompleteEnvirons('#all-environs', [])
1411
1412def doNothing(**ignored): pass
1413main.Append(BUILDERS = {'Dummy': Builder(action=MakeAction(doNothing, None))})
1414
1415# The final target to which all the original targets ultimately get attached.
1416main.Dummy('#all-targets', '#all-environs')
1417BUILD_TARGETS[:] = ['#all-targets']
1418
1419###################################################
1420#
1421# Define build environments for selected configurations.
1422#
1423###################################################
1424
1425for variant_path in variant_paths:
1426    if not GetOption('silent'):
1427        print "Building in", variant_path
1428
1429    # Make a copy of the build-root environment to use for this config.
1430    env = main.Clone()
1431    env['BUILDDIR'] = variant_path
1432
1433    # variant_dir is the tail component of build path, and is used to
1434    # determine the build parameters (e.g., 'ALPHA_SE')
1435    (build_root, variant_dir) = splitpath(variant_path)
1436
1437    # Set env variables according to the build directory config.
1438    sticky_vars.files = []
1439    # Variables for $BUILD_ROOT/$VARIANT_DIR are stored in
1440    # $BUILD_ROOT/variables/$VARIANT_DIR so you can nuke
1441    # $BUILD_ROOT/$VARIANT_DIR without losing your variables settings.
1442    current_vars_file = joinpath(build_root, 'variables', variant_dir)
1443    if isfile(current_vars_file):
1444        sticky_vars.files.append(current_vars_file)
1445        if not GetOption('silent'):
1446            print "Using saved variables file %s" % current_vars_file
1447    else:
1448        # Build dir-specific variables file doesn't exist.
1449
1450        # Make sure the directory is there so we can create it later
1451        opt_dir = dirname(current_vars_file)
1452        if not isdir(opt_dir):
1453            mkdir(opt_dir)
1454
1455        # Get default build variables from source tree.  Variables are
1456        # normally determined by name of $VARIANT_DIR, but can be
1457        # overridden by '--default=' arg on command line.
1458        default = GetOption('default')
1459        opts_dir = joinpath(main.root.abspath, 'build_opts')
1460        if default:
1461            default_vars_files = [joinpath(build_root, 'variables', default),
1462                                  joinpath(opts_dir, default)]
1463        else:
1464            default_vars_files = [joinpath(opts_dir, variant_dir)]
1465        existing_files = filter(isfile, default_vars_files)
1466        if existing_files:
1467            default_vars_file = existing_files[0]
1468            sticky_vars.files.append(default_vars_file)
1469            print "Variables file %s not found,\n  using defaults in %s" \
1470                  % (current_vars_file, default_vars_file)
1471        else:
1472            print "Error: cannot find variables file %s or " \
1473                  "default file(s) %s" \
1474                  % (current_vars_file, ' or '.join(default_vars_files))
1475            Exit(1)
1476
1477    # Apply current variable settings to env
1478    sticky_vars.Update(env)
1479
1480    help_texts["local_vars"] += \
1481        "Build variables for %s:\n" % variant_dir \
1482                 + sticky_vars.GenerateHelpText(env)
1483
1484    # Process variable settings.
1485
1486    if not have_fenv and env['USE_FENV']:
1487        print "Warning: <fenv.h> not available; " \
1488              "forcing USE_FENV to False in", variant_dir + "."
1489        env['USE_FENV'] = False
1490
1491    if not env['USE_FENV']:
1492        print "Warning: No IEEE FP rounding mode control in", variant_dir + "."
1493        print "         FP results may deviate slightly from other platforms."
1494
1495    if env['EFENCE']:
1496        env.Append(LIBS=['efence'])
1497
1498    if env['USE_KVM']:
1499        if not have_kvm:
1500            print "Warning: Can not enable KVM, host seems to lack KVM support"
1501            env['USE_KVM'] = False
1502        elif not is_isa_kvm_compatible(env['TARGET_ISA']):
1503            print "Info: KVM support disabled due to unsupported host and " \
1504                "target ISA combination"
1505            env['USE_KVM'] = False
1506
1507    # Warn about missing optional functionality
1508    if env['USE_KVM']:
1509        if not main['HAVE_PERF_ATTR_EXCLUDE_HOST']:
1510            print "Warning: perf_event headers lack support for the " \
1511                "exclude_host attribute. KVM instruction counts will " \
1512                "be inaccurate."
1513
1514    # Save sticky variable settings back to current variables file
1515    sticky_vars.Save(current_vars_file, env)
1516
1517    if env['USE_SSE2']:
1518        env.Append(CCFLAGS=['-msse2'])
1519
1520    # The src/SConscript file sets up the build rules in 'env' according
1521    # to the configured variables.  It returns a list of environments,
1522    # one for each variant build (debug, opt, etc.)
1523    SConscript('src/SConscript', variant_dir = variant_path, exports = 'env')
1524
1525def pairwise(iterable):
1526    "s -> (s0,s1), (s1,s2), (s2, s3), ..."
1527    a, b = itertools.tee(iterable)
1528    b.next()
1529    return itertools.izip(a, b)
1530
1531# Create false dependencies so SCons will parse ISAs, establish
1532# dependencies, and setup the build Environments serially. Either
1533# SCons (likely) and/or our SConscripts (possibly) cannot cope with -j
1534# greater than 1. It appears to be standard race condition stuff; it
1535# doesn't always fail, but usually, and the behaviors are different.
1536# Every time I tried to remove this, builds would fail in some
1537# creative new way. So, don't do that. You'll want to, though, because
1538# tests/SConscript takes a long time to make its Environments.
1539for t1, t2 in pairwise(sorted(all_isa_deps.iterkeys())):
1540    main.Depends('#%s-deps'     % t2, '#%s-deps'     % t1)
1541    main.Depends('#%s-environs' % t2, '#%s-environs' % t1)
1542
1543# base help text
1544Help('''
1545Usage: scons [scons options] [build variables] [target(s)]
1546
1547Extra scons options:
1548%(options)s
1549
1550Global build variables:
1551%(global_vars)s
1552
1553%(local_vars)s
1554''' % help_texts)
1555