style: [patch 1/22] use /r/3648/ to reorganize includes

base: add symbol support for dynamic libraries

Libraries are loaded into the process address space using the
mmap system call. Conveniently, this happens to be a good
time to update the process symbol table with the library's
incoming symbols so we handle the table update from within the
system call.

This works just like an application's normal symbols. The only
difference between a dynamic library and a main executable is
when the symbol table update occurs. The symbol table update for
an executable happens at program load time and is finished before
the process ever begins executing. Since dynamic linking happens
at runtime, the symbol loading happens after the library is
first loaded into the process address space. The library binary
is examined at this time for a symbol section and that section
is parsed for symbol types with specific bindings (global,
local, weak). Subsequently, these symbols are added to the table
and are available for use by gem5 for things like trace
generation.

Checkpointing should work just as it did previously. The address
space (and therefore the library) will be recorded and the symbol
table will be entirely recorded. (It's not possible to do anything
clever like checkpoint a program and then load the program back
with different libraries with LD_LIBRARY_PATH, because the
library becomes part of the address space after being loaded.)

sim: Refactor the serialization base class

Objects that are can be serialized are supposed to inherit from the
Serializable class. This class is meant to provide a unified API for
such objects. However, so far it has mainly been used by SimObjects
due to some fundamental design limitations. This changeset redesigns
to the serialization interface to make it more generic and hide the
underlying checkpoint storage. Specifically:

* Add a set of APIs to serialize into a subsection of the current
object. Previously, objects that needed this functionality would
use ad-hoc solutions using nameOut() and section name
generation. In the new world, an object that implements the
interface has the methods serializeSection() and
unserializeSection() that serialize into a named /subsection/ of
the current object. Calling serialize() serializes an object into
the current section.

* Move the name() method from Serializable to SimObject as it is no
longer needed for serialization. The fully qualified section name
is generated by the main serialization code on the fly as objects
serialize sub-objects.

* Add a scoped ScopedCheckpointSection helper class. Some objects
need to serialize data structures, that are not deriving from
Serializable, into subsections. Previously, this was done using
nameOut() and manual section name generation. To simplify this,
this changeset introduces a ScopedCheckpointSection() helper
class. When this class is instantiated, it adds a new /subsection/
and subsequent serialization calls during the lifetime of this
helper class happen inside this section (or a subsection in case
of nested sections).

* The serialize() call is now const which prevents accidental state
manipulation during serialization. Objects that rely on modifying
state can use the serializeOld() call instead. The default
implementation simply calls serialize(). Note: The old-style calls
need to be explicitly called using the
serializeOld()/serializeSectionOld() style APIs. These are used by
default when serializing SimObjects.

* Both the input and output checkpoints now use their own named
types. This hides underlying checkpoint implementation from
objects that need checkpointing and makes it easier to change the
underlying checkpoint storage code.

Checkpoint: Make system serialize call children

This patch changes how the serialization of the system works. The base
class had a non-virtual serialize and unserialize, that was hidden by
a function with the same name for a number of subclasses (most likely
not intentional as the base class should have been virtual). A few of
the derived systems had no specialization at all (e.g. Power and x86
that simply called the System::serialize), but MIPS and Alpha adds
additional symbol table entries to the checkpoint.

Instead of overriding the virtual function, the additional entries are
now printed through a virtual function (un)serializeSymtab. The reason
for not calling System::serialize from the two related systems is that
a follow up patch will require the system to also serialize the
PhysicalMemory, and if this is done in the base class if ends up being
between the general parts and the specialized symbol table.

With this patch, the checkpoint is not modified, as the order of the
segments is unchanged.

System: Move code in initState() back into constructor whenever possible.

The change to port proxies recently moved code out of the constructor into
initState(). This is needed for code that loads data into memory, however
for code that setups symbol tables, kernel based events, etc this is the wrong
thing to do as that code is only called when a checkpoint isn't being restored
from.

MEM: Add port proxies instead of non-structural ports

Port proxies are used to replace non-structural ports, and thus enable
all ports in the system to correspond to a structural entity. This has
the advantage of accessing memory through the normal memory subsystem
and thus allowing any constellation of distributed memories, address
maps, etc. Most accesses are done through the "system port" that is
used for loading binaries, debugging etc. For the entities that belong
to the CPU, e.g. threads and thread contexts, they wrap the CPU data
port in a port proxy.

The following replacements are made:
FunctionalPort > PortProxy
TranslatingPort > SETranslatingPortProxy
VirtualPort > FSTranslatingPortProxy

includes: sort all includes

More minor gdb-related cleanup.
Found several more stale includes and forward decls.

Major changes to how SimObjects are created and initialized. Almost all
creation and initialization now happens in python. Parameter objects
are generated and initialized by python. The .ini file is now solely for
debugging purposes and is not used in construction of the objects in any
way.

Merge zizzer:/bk/newmem
into zower.eecs.umich.edu:/eecshome/m5/newmem

src/arch/sparc/isa/formats/mem/util.isa:
src/arch/sparc/isa_traits.hh:
src/arch/sparc/system.cc:
Hand Merge

Initial work to make remote gdb available in SE mode. This is completely untested.

make our code a little more standards compliant
pretty close to compiling w/ suns compiler

briefly:
add dummy return after panic()/fatal()
split out flags by compiler vendor
include cstring and cmath where appropriate
use std namespace for string ops

SConstruct:
Add code to detect compiler and choose cflags based on detected compiler
Fix zlib check to work with suncc
src/SConscript:
split out flags by compiler vendor
src/arch/sparc/isa/decoder.isa:
use correct namespace for sqrt
src/arch/sparc/isa/formats/basic.isa:
add dummy return around panic
src/arch/sparc/isa/formats/integerop.isa:
use correct namespace for stringops
src/arch/sparc/isa/includes.isa:
include cstring and cmath where appropriate
src/arch/sparc/isa_traits.hh:
remove dangling comma
src/arch/sparc/system.cc:
dummy return to make sun cc front end happy
src/arch/sparc/tlb.cc:
src/base/compression/lzss_compression.cc:
use std namespace for string ops
src/arch/sparc/utility.hh:
no reason to say something is unsigned unsigned int
src/base/compression/null_compression.hh:
dummy returns to for suncc front end
src/base/cprintf.hh:
use standard variadic argument syntax instead of gnuc specefic renaming
src/base/hashmap.hh:
don't need to define hash for suncc
src/base/hostinfo.cc:
need stdio.h for sprintf
src/base/loader/object_file.cc:
munmap is in std namespace not null
src/base/misc.hh:
use M5 generic noreturn macros
use standard variadic macro __VA_ARGS__
src/base/pollevent.cc:
we need file.h for file flags
src/base/random.cc:
mess with include files to make suncc happy
src/base/remote_gdb.cc:
malloc memory for function instead of having a non-constant in an array size
src/base/statistics.hh:
use std namespace for floor
src/base/stats/text.cc:
include math.h for rint (cmath won't work)
src/base/time.cc:
use suncc version of ctime_r
src/base/time.hh:
change macro to work with both gcc and suncc
src/base/timebuf.hh:
include cstring from memset and use std::
src/base/trace.hh:
change variadic macros to be normal format
src/cpu/SConscript:
add dummy returns where appropriate
src/cpu/activity.cc:
include cstring for memset
src/cpu/exetrace.hh:
include cstring fro memcpy
src/cpu/simple/base.hh:
add dummy return for panic
src/dev/baddev.cc:
src/dev/pciconfigall.cc:
src/dev/platform.cc:
src/dev/sparc/t1000.cc:
add dummy return where appropriate
src/dev/ide_atareg.h:
make define work for both gnuc and suncc
src/dev/io_device.hh:
add dummy returns where approirate
src/dev/pcidev.hh:
src/mem/cache/cache_impl.hh:
src/mem/cache/miss/blocking_buffer.cc:
src/mem/cache/tags/lru.hh:
src/mem/cache/tags/split.hh:
src/mem/cache/tags/split_lifo.hh:
src/mem/cache/tags/split_lru.hh:
src/mem/dram.cc:
src/mem/packet.cc:
src/mem/port.cc:
include cstring for string ops
src/dev/sparc/mm_disk.cc:
add dummy return where appropriate
include cstring for string ops
src/mem/cache/miss/blocking_buffer.hh:
src/mem/port.hh:
Add dummy return where appropriate
src/mem/cache/tags/iic.cc:
cast hastSets to double for log() call
src/mem/physical.cc:
cast pmemAddr to char* for munmap
src/sim/byteswap.hh:
make define work for suncc and gnuc

Load the hypervisor symbols twice, once with an address mask so that we can get symbols for where it's copied to in memory
Add the ability to use an address mask for symbol loading
Rather then silently failing on platform accesses panic
Move BadAddr/IsaFake no Device from Tsunami
Let the system kernel be none, but warn about it

configs/common/FSConfig.py:
We don't have a kernel for sparc yet
src/arch/sparc/system.cc:
Load the hypervisor symbols twice, once with an address mask so that we can get symbols for where it's copied to in memory
src/base/loader/aout_object.cc:
src/base/loader/aout_object.hh:
src/base/loader/ecoff_object.cc:
src/base/loader/ecoff_object.hh:
src/base/loader/elf_object.cc:
src/base/loader/elf_object.hh:
src/base/loader/object_file.hh:
src/base/loader/raw_object.cc:
src/base/loader/raw_object.hh:
Add the ability to use an address mask for symbol loading
src/dev/sparc/t1000.cc:
Rather then silently failing on platform accesses panic
src/dev/sparc/t1000.hh:
fix up a couple of platform comments
src/python/m5/objects/Bus.py:
src/python/m5/objects/Device.py:
src/python/m5/objects/T1000.py:
src/python/m5/objects/Tsunami.py:
Move BadAddr/IsaFake no Device from Tsunami
src/python/m5/objects/System.py:
Let kernel be none
src/sim/system.cc:
Let the system kernel be none, but warn about it

Add in rom/rams for the nvram, hypervisor description, and partition description.

Get SPARC to the point that it starts running. Add ability to load the ROM bin files, cleanup lockstep printing a bit
Since we don't have a platform yet, you need to comment out the default responder stuff in Bus.py to make it work.

SConstruct:
Add TARGET_ISA to the list of environment variables that end up in the build_env for python
configs/common/FSConfig.py:
add a simple SPARC system to being testing with, you'll need to change makeLinuxAlphaSystem to makeSparcSystem in fs.py for now
src/SConscript:
add a raw file object, at least until we get more info about how to compile openboot properly
src/arch/sparc/system.cc:
src/arch/sparc/system.hh:
add parameters for ROM files (OBP/Reset/Hypervisor), a ROM, load files into ROM
src/base/loader/object_file.cc:
src/base/loader/object_file.hh:
add option to try raw when nothing works
src/cpu/exetrace.cc:
cleanup lockstep printing a little bit
src/cpu/m5legion_interface.h:
change the instruction to be 32 bits because it is
src/mem/physical.cc:
fix assert that doesn't work if memory starts somewhere above 0
src/python/m5/objects/BaseCPU.py:
Add if statement to choose between sparc tlbs and alpha tlbs
src/python/m5/objects/System.py:
Add a sparc system that sets the rom addresses correctly
src/python/m5/params.py:
add the ability to add Addr() together

Compilation fixes.

remove traces of binning

add system.mem_mode = ['timing', 'atomic']
update scripts acordingly

configs/test/SysPaths.py:
new syspaths from nate, this one allows you to set script, binary, and disk paths like
system.dir = 'aouaou' in your script
configs/test/fs.py:
update for system mem_mode
Put small checkpoint example
Make clock 1THz
configs/test/test.py:
src/arch/alpha/freebsd/system.cc:
src/arch/alpha/linux/system.cc:
src/arch/alpha/system.cc:
src/arch/alpha/tru64/system.cc:
src/arch/sparc/system.cc:
src/python/m5/objects/System.py:
src/sim/system.cc:
src/sim/system.hh:
update for system mem_mode
src/dev/io_device.cc:
Use time returned from sendAtomic to delay

Updated Authors from bk prs info

split off fullsystem and se iprs into two functions to remove lots of #ifs
setup all initialization stuff for UA2005
Setup fullsys build options
Start to make fullsystem compile

src/arch/sparc/vtophys.cc:
src/arch/sparc/vtophys.hh:
RCS to BitKeeper
src/arch/sparc/vtophys.cc:
src/arch/sparc/vtophys.hh:
Add support for doing virtual to physical translation using the in-memory
page table
src/arch/sparc/vtophys.cc:
a tad bit of error checking
src/arch/sparc/vtophys.hh:
Cleanup of full-system global variables, primarily in simple_cpu.cc,
to allow multi-system simulations. (Multiple systems not yet yested
though.) Also changes to build sim_smt in full-system mode (though
with only SimpleCPU and not the full timing CPU for now).

Still to do: minimize changes in SimpleCPU code between full-system
and application modes... way too many ifdefs there. Much of the
full-system stuff moved into SimpleCPU should be put in a new System
object to allow multiprocessor simulations.

Converted last remaining modules from C to C++ (mostly in /old).
Renamed all .c files to .cc and a few .h files to .hh.

Renamed architecture-specific files in arch/$TARGET from
$TARGET.{cc,hh,def} to machine.{cc,hh,def} to get rid of pointless
intermediate files in object directory. Split exo-specific
definitions out of machine.hh into machine_exo.h.

Specifics:

In machine.def, null resource descriptors must be FUClamd_NA (and not
NA) to pass C++ type checking.

Enhanced error checking/reporting in bas
src/arch/sparc/vtophys.cc:
- Get rid of my String class, the Vector class, the bitvector class, and my
doubly linked list class.
- Convert tokenize, to_number (formerly StringToNumber) and eat_white to
function on stl strings.
- Change most cases of char * and const char * to string, or const string &
- Some formatting and style nits, but not too many.
src/arch/sparc/vtophys.cc:
simplify
src/arch/sparc/vtophys.cc:

Renamed SimpleCPU::(read|write)_(byte|half|word|qword) to just read &
write, overloaded on the type of the 'data' argument. Merged the
full-system and non-full-system implementations of these eight
original functions into two common template functions.

To support this, also renamed (read|write)[1248] on memory_object and
derivatives to just read & write, again overloaded on the type of the
'data' argument. Many of these functions could now be condensed into
a few template functions (though with a level of indirection so that
the interface can remain virtual). I did not do that though.
src/arch/sparc/vtophys.cc:
First pass at compiling with gcc 3.x. Lots of "std::" in header files,
"using namespace std" in source files. (Note policy of not putting "using"
statements in headers or before includes in sources.)

Still not able to compile with gcc 3.2.
Errors:
- Can't create an ifstream from a file descriptor anymore (breaks IniFile).
- "`class MSHR::MSHRegister' is private" errors in mshr.cc and prefetch_cache.cc:
not clear why since it's in the public part of the class declaration.
- cpu.cc:879: can't match a reference and 0 (specifically "no match for `bool ?
SimObjectParam<PipeTrace*>& : int' operator")
- pipetrace.cc: "invalid conversion from `int' to `std::_Ios_Fmtflags'"
Warnings:
- strstream now deprecated... needs some rewriting in sat_counter.hh
and hybrid_pred.hh (need to get all that code out of the headers anyway)
- trace.hh macro problem: cpp now says 'pasting "::" and "Event" does not
give a valid preprocessing token'
- major "implicit typename" issues in base/sized.hh
src/arch/sparc/vtophys.cc:
src/arch/sparc/vtophys.hh:
Implement some interval statistics for full system mode.
Create a callpal function that is called when a callpal occurs so it's easier
to manipulate the statics.
Rework the vtophys stuff to make it a bit cleaner.
src/arch/sparc/vtophys.cc:
src/arch/sparc/vtophys.hh:
Get rid of almost all old-style object names. This commit is equivalent
to running the following script on the current head:

#! /bin/sh

find \( -name '*.cc' -o -name '*.hh' \) -exec perl -pi -e '\
s/\bmemory_object\b(?!\.hh)/FunctionalMemory/g;\
s/\bvirtual_memory\b(?!\.hh)/VirtualMemory/g;\
s/\bmain_memory\b(?!\.hh)/MainMemory/g;\
s/\bphysical_memory\b(?!\.hh)/PhysicalMemory/g;\
s/\bspec_memory\b(?!\.hh)/SpeculativeMemory/g;\
s/\bMemObj\b(?!\.hh)/TimingMemObj/g;\
s/\bmemory_translation\b(?!\.hh)/AddressTranslator/g;\
s/\balpha_tlb\b(?!\.hh)/AlphaTlb/g;\
s/\balpha_itb\b(?!\.hh)/AlphaItb/g;\
s/\balpha_dtb\b(?!\.hh)/AlphaDtb/g;\
s/\bmemory_controller\b(?!\.hh)/MemoryController/g;\
s/\bstorebuffer_t\b(?!\.hh)/StoreBuffer/g;\
s/\bstorebuffer_entry_t\b(?!\.hh)/StoreBufferEntry/g;\
s/\bcreate_vector_t\b(?!\.hh)/CreateVector/g;\
s/\bcv_spec_state\b(?!\.hh)/CreateVecSpecState/g;\
s/\bspec_state_list\b(?!\.hh)/SpecStateList/g;\
s/\bdyn_inst_t\b(?!\.hh)/DynInst/g;' {} \;
src/arch/sparc/vtophys.cc:
since cprintf properly deals with 64-bit types, stop using FMT* as much as
possible
src/arch/sparc/vtophys.cc:
src/arch/sparc/vtophys.hh:
Change byte_t etc. to C99 standard int8_t etc.
Other than old/host.h, all other changes were produced by this script:

#! /bin/sh

find \( -name '*.cc' -o -name '*.hh' -o -name '*.c' -o -name '*.h' -o -name 'machine.def' \) -exec perl -pi -e '\
s/\bbyte_t\b(?!\.hh)/uint8_t/g;\
s/\bsbyte_t\b(?!\.hh)/int8_t/g;\
s/\bhalf_t\b(?!\.hh)/uint16_t/g;\
s/\bshalf_t\b(?!\.hh)/int16_t/g;\
s/\bword_t\b(?!\.hh)/uint32_t/g;\
s/\bsword_t\b(?!\.hh)/int32_t/g;\
s/\bqword_t\b(?!\.hh)/uint64_t/g;\
s/\bsqword_t\b(?!\.hh)/int64_t/g;\
s/\bbool_t\b(?!\.hh)/bool/g;\
s/\bdfloat_t\b(?!\.hh)/double/g;\
s/\bsfloat_t\b(?!\.hh)/float/g;' {} \;
src/arch/sparc/vtophys.cc:
src/arch/sparc/vtophys.hh:
Add CVS Id tags
src/arch/sparc/vtophys.cc:
src/arch/sparc/vtophys.hh:
Massive renaming to (almost) eliminate all md_* and MD_* names
in preparation for total exorcism of machine.def.

Most of the changes in this commit were performed with the
following perl script (perl -pi <script> <files>). A small
amount of manual fixup was needed to (mostly getting rid of
the Addr typedefs in the various memory objects now that
the former md_addr_t has that name).

# rename machine-dependent types and constants (will be moving into ISA traits object)
s/md_addr_t/Addr/g;
s/md_intreg_t/IntReg/g;
s/md_gpr_t/IntRegFile/g;
s/md_fpreg_t/FloatReg/g;
s/md_fpr_t/FloatRegFile/g;
s/md_ctrlreg_t/MiscReg/g;
s/md_ctrl_t/MiscRegFile/g;
s/md_ipr_t/InternalProcReg/g;
s/md_anyreg_t/AnyReg/g;
s/md_inst_t/MachInst/g;
s/regs_t/RegFile/g;
# manually fix declaration in old/regs.h and a few forward decls
s/struct RegFile/RegFile/g;
s/MD_NUM_IREGS/NumIntRegs/g;
s/MD_NUM_FREGS/NumFloatRegs/g;
s/MD_NUM_CREGS/NumMiscRegs/g;
s/MD_IPR_NUM/NumInternalProcRegs/g;
s/MD_TOTAL_REGS/TotalNumRegs/g;
s/MD_REG_ZERO/ZeroReg/g;
src/arch/sparc/vtophys.cc:
src/arch/sparc/vtophys.hh:
New ISA description system. No more machine.def!
Instructions are now decoded into StaticInst objects, and all static
instruction properties (including execution behavior) are associated
with those objects. Extended documentation in progress.
Currently supports Alpha only; PISA will not compile.
Use END_OF_MACHINE_DOT_DEF tag to extract previous version.
src/arch/sparc/vtophys.cc:
get rid of MD_IPR_foo and call it IPR_foo
add some comments to describe what the various PALtemp registers do
formatting
src/arch/sparc/vtophys.cc:
src/arch/sparc/vtophys.hh:
license
src/arch/sparc/vtophys.cc:
src/arch/sparc/vtophys.hh:
a little style
src/arch/sparc/vtophys.cc:
src/arch/sparc/vtophys.hh:
Add attribution to license.
src/arch/sparc/vtophys.cc:
src/arch/sparc/vtophys.hh:
Make include paths explicit.
src/arch/sparc/vtophys.cc:
src/arch/sparc/vtophys.hh:
CopyData and CopyString moved from kernel.cc to vtophys.cc
kernel.cc and kernel.hh moved to kern/tru64
src/arch/sparc/vtophys.hh:
Include isa_traits.hh for Addr
src/arch/sparc/vtophys.cc:
formatting fixes
src/arch/sparc/vtophys.cc:
fix up vtophys to deal with translations if there
is no ptbr, and to deal with PAL addresses
add ptomem which is just a wrapper for dma_addr
src/arch/sparc/vtophys.hh:
add ptomem which is a wrapper for dma_addr with the
same usage as vtomem
src/arch/sparc/vtophys.cc:
Fix to remote debugger while in PAL code
src/arch/sparc/vtophys.cc:
Remote an old hack that is now unnecessary
src/arch/sparc/vtophys.cc:
Removed buggy code that tries to fix PAL addresses (may cause problems
while trying to debug in PAL code, but that should do this fix outside
of vtophys)
src/arch/sparc/vtophys.cc:
src/arch/sparc/vtophys.hh:
Updated Copyright
src/arch/sparc/vtophys.cc:
added back some code andrew removed and couldn't remember why.
src/arch/sparc/vtophys.cc:
src/arch/sparc/vtophys.hh:
rename CopyData to CopyOut and implement CopyIn to copy data
from the simulator into the simulatee
src/arch/sparc/vtophys.cc:
fixed a bad merge from linux<->tru64
src/arch/sparc/vtophys.cc:
Check max address pal can be at so we don't do the wrong conversion
if gdb asks for an unaligned access.
src/arch/sparc/vtophys.cc:
PGOFSET -> ALPHA_PGOFSET to avoid include file problems
src/arch/sparc/vtophys.cc:
src/arch/sparc/vtophys.hh:
in the arch/alpha directory we should use arch/alpha, not
targetarch. sort includes while we're here.
src/arch/sparc/vtophys.cc:
use new constants, functions and structs to clean up the
vtophys code.
src/arch/sparc/vtophys.hh:
Clean up a little bit and make the protypes match new changes.
src/arch/sparc/vtophys.cc:
deal with isa addition
src/arch/sparc/vtophys.cc:
shuffle files around for new directory structure
src/arch/sparc/vtophys.cc:
src/arch/sparc/vtophys.hh:
Remove RCS Id string
src/arch/sparc/vtophys.cc:
src/arch/sparc/vtophys.hh:
Update copyright dates and author list
src/arch/sparc/vtophys.cc:
Added a using directive for AlphaISA
src/arch/sparc/vtophys.hh:
Added the AlphaISA namespace specifier where needed
src/arch/sparc/vtophys.hh:
Made Addr a global type
src/arch/sparc/vtophys.cc:
Change access to the IPR to go through the XC.
src/arch/sparc/vtophys.cc:
Avoid directly accessing objects within the XC.
src/arch/sparc/vtophys.cc:
src/arch/sparc/vtophys.hh:
fixed for new memory system
put in namespace AlphaISA
src/arch/alpha/vtophys.cc:
src/arch/alpha/vtophys.hh:
Remove authors from copyright.
src/arch/sparc/vtophys.cc:
bk cp alpha/vtophys.cc sparc/vtophys.cc
src/arch/sparc/vtophys.hh:
bk cp alpha/vtophys.hh sparc/vtophys.hh
src/arch/sparc/SConscript:
remove fullsystem files that don't exist
src/arch/sparc/isa_traits.hh:
split off fullsystem and se iprs into two functions to remove lots of #ifs
src/arch/sparc/regfile.hh:
split off fullsystem and se iprs into two functions to remove lots of #ifs
setup all initialization stuff for UA2005
src/arch/sparc/system.cc:
src/arch/sparc/system.hh:
Add system level tick storage to make stick be syncronized across multiple processors
src/arch/sparc/vtophys.hh:
start to create a vtophys for Sparc
src/base/loader/symtab.hh:
Addr is defined in sim/host.hh

New directory structure:
- simulator source now in 'src' subdirectory
- imported files from 'ext' repository
- support building in arbitrary places, including
outside of the source tree. See comment at top
of SConstruct file for more details.
Regression tests are temporarily disabled; that
syetem needs more extensive revisions.

SConstruct:
Update for new directory structure.
Modify to support build trees that are not subdirectories
of the source tree. See comment at top of file for
more details.
Regression tests are temporarily disabled.
src/arch/SConscript:
src/arch/isa_parser.py:
src/python/SConscript:
Update for new directory structure.