sim-se: const for loader's loadSection param

The port proxy can be declared as a reference to a const proxy
rather than just a reference to a proxy.

Change-Id: I4640b0c5f33e2334c1e7630131f78607ced40a34
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/12301
Maintainer: Brandon Potter <Brandon.Potter@amd.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>

arch-riscv: Enable support for riscv 32-bit in SE mode.

This patch splits up the riscv SE mode support for 32 and 64-bit.
A future patch will add support for decoding rv32 instructions.

Change-Id: Ia79ae19f753caf94dc7e5830a6630efb94b419d7
Signed-off-by: Austin Harris <austinharris@utexas.edu>
Reviewed-on: https://gem5-review.googlesource.com/c/15355
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Alec Roelke <alec.roelke@gmail.com>
Maintainer: Alec Roelke <alec.roelke@gmail.com>

misc: Rename misc.(hh|cc) to logging.(hh|cc)

These files aren't a collection of miscellaneous stuff, they're the
definition of the Logger interface, and a few utility macros for
calling into that interface (panic, warn, etc.).

Change-Id: I84267ac3f45896a83c0ef027f8f19c5e9a5667d1
Reviewed-on: https://gem5-review.googlesource.com/6226
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Gabe Black <gabeblack@google.com>

base: fix small memory leak in the ELF loader

arch: [Patch 1/5] Added RISC-V base instruction set RV64I

First of five patches adding RISC-V to GEM5. This patch introduces the
base 64-bit ISA (RV64I) in src/arch/riscv for use with syscall emulation.
The multiply, floating point, and atomic memory instructions will be added
in additional patches, as well as support for more detailed CPU models.
The loader is also modified to be able to parse RISC-V ELF files, and a
"Hello world\!" example for RISC-V is added to test-progs.

Patch 2 will implement the multiply extension, RV64M; patch 3 will implement
the floating point (single- and double-precision) extensions, RV64FD;
patch 4 will implement the atomic memory instructions, RV64A, and patch 5
will add support for timing, minor, and detailed CPU models that is missing
from the first four patches (such as handling locked memory).

[Removed several unused parameters and imports from RiscvInterrupts.py,
RiscvISA.py, and RiscvSystem.py.]
[Fixed copyright information in RISC-V files copied from elsewhere that had
ARM licenses attached.]
[Reorganized instruction definitions in decoder.isa so that they are sorted
by opcode in preparation for the addition of ISA extensions M, A, F, D.]
[Fixed formatting of several files, removed some variables and
instructions that were missed when moving them to other patches, fixed
RISC-V Foundation copyright attribution, and fixed history of files
copied from other architectures using hg copy.]
[Fixed indentation of switch cases in isa.cc.]
[Reorganized syscall descriptions in linux/process.cc to remove large
number of repeated unimplemented system calls and added implmementations
to functions that have received them since it process.cc was first
created.]
[Fixed spacing for some copyright attributions.]
[Replaced the rest of the file copies using hg copy.]
[Fixed style check errors and corrected unaligned memory accesses.]
[Fix some minor formatting mistakes.]
Signed-off by: Alec Roelke

Signed-off by: Jason Lowe-Power <jason@lowepower.com>

base: Fix inverted check in ELF .text size warning

base: Convert ELF .text size check assertion to a warning

The ELF loader currently has an assertion that checks if the size of a
loaded .text secion is non-zero. This is useful in the general case as
an empty text section normally indicates that there is something
strange with the ELF file. However, asserting isn't very useful. This
changeset converts the assert into a warning that tells the user that
something strange is happening.

Change-Id: I313e17847b50a0eca00f6bd00a54c610d626c0f0
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>

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.)

base: style cleanup for ObjectFile and ElfObject

base: support dynamic loading of Linux ELF objects in SE mode

style: fix missing spaces in control statements

Result of running 'hg m5style --skip-all --fix-control -a'.

style: remove trailing whitespace

Result of running 'hg m5style --skip-all --fix-white -a'.

base: remove fd from object loaders

All the object loaders directly examine the (already completely loaded
by object_file.cc) memory image. There is no current motivation to
keep the fd around.

arch, base, dev, kern, sym: FreeBSD support

This adds support for FreeBSD/aarch64 FS and SE mode (basic set of syscalls only)

Committed by: Nilay Vaish <nilay@cs.wisc.edu>

misc: Fix a number of unitialised variables and members

Static analysis unearther a bunch of uninitialised variables and
members, and this patch addresses the problem. In all cases these
omissions seem benign in the end, but at least fixing them means less
false positives next time round.

arm: Add support for ARMv8 (AArch64 & AArch32)

Note: AArch64 and AArch32 interworking is not supported. If you use an AArch64
kernel you are restricted to AArch64 user-mode binaries. This will be addressed
in a later patch.

Note: Virtualization is only supported in AArch32 mode. This will also be fixed
in a later patch.

Contributors:
Giacomo Gabrielli (TrustZone, LPAE, system-level AArch64, AArch64 NEON, validation)
Thomas Grocutt (AArch32 Virtualization, AArch64 FP, validation)
Mbou Eyole (AArch64 NEON, validation)
Ali Saidi (AArch64 Linux support, code integration, validation)
Edmund Grimley-Evans (AArch64 FP)
William Wang (AArch64 Linux support)
Rene De Jong (AArch64 Linux support, performance opt.)
Matt Horsnell (AArch64 MP, validation)
Matt Evans (device models, code integration, validation)
Chris Adeniyi-Jones (AArch64 syscall-emulation)
Prakash Ramrakhyani (validation)
Dam Sunwoo (validation)
Chander Sudanthi (validation)
Stephan Diestelhorst (validation)
Andreas Hansson (code integration, performance opt.)
Eric Van Hensbergen (performance opt.)
Gabe Black

loader: Load weak symbols for function tracing

base: load weak symbols from object file
Without loading weak symbols into gem5, some function names and the given PC
cannot correspond correctly, because the binding attributes of unction names
in an ELF file are not only STB_GLOBAL or STB_LOCAL, but also STB_WEAK. This
patch adds a function for loading weak symbols.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>

loader: initialize all memory in the ObjectFile objects.

Some bare metal build flows seem to build binaries that we aren't necessarily
expecting. Initialize everything to 0, so we don't make any assumptions about
what is or isn't in the binary.

MEM: Make port proxies use references rather than pointers

This patch is adding a clearer design intent to all objects that would
not be complete without a port proxy by making the proxies members
rathen than dynamically allocated. In essence, if NULL would not be a
valid value for the proxy, then we avoid using a pointer to make this
clear.

The same approach is used for the methods using these proxies, such as
loadSections, that now use references rather than pointers to better
reflect the fact that NULL would not be an acceptable value (in fact
the code would break and that is how this patch started out).

Overall the concept of "using a reference to express unconditional
composition where a NULL pointer is never valid" could be done on a
much broader scale throughout the code base, but for now it is only
done in the locations affected by the proxies.

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

Loader: Handle bad section names when loading an ELF file.

If there's a problem when reading the section names from a supposed ELF file,
this change makes gem5 print an error message as returned by libelf and die.
Previously these sorts of errors would make gem5 segfault when it tried to
access the section name through a NULL pointer.

trace: reimplement the DTRACE function so it doesn't use a vector
At the same time, rename the trace flags to debug flags since they
have broader usage than simply tracing. This means that
--trace-flags is now --debug-flags and --trace-help is now --debug-help

includes: sort all includes

style: fix sorting of includes and whitespace in some files

Loader: Don't insert symbols into the symbol table that begin wiht '$'.

Loader: Use address mask provided to load*Symbols when loading the symbols from the symbol table.

ARM: Detect thumb mode elf images.

POWER: Add support for the Power ISA

This adds support for the 32-bit, big endian Power ISA. This supports both
integer and floating point instructions based on the Power ISA Book I v2.06.

ARM: Detect OABI binaries and complain that they're no-longer supported.

X86: Make the loader recognize 32 bit x86 processes.

This brings M5 closer to modernity - the kernel being advertised is newer so it won't die on binaries compiled with newer glibc's, and enables use of TLS-toolchain built binaries for ALPHA_SE by putting auxiliary vectors on the stack. There are some comments in the code to help. Finally, stats changes for ALPHA are from slight perturbations to the initial stack frame, all minimal diffs.

misc: remove #include <cassert> from misc.hh since not everyone needs it.

style: Remove non-leading tabs everywhere they shouldn't be. Developers should configure their editors to not insert tabs

MIPS: Check endianness of binaries in SE mode.

Add base ARM code to M5

Loader: Identify sections based on virtual addresses, and set the LoadAddrMask correctly for x86.

ELF Loader: Use physical addresses instead of virtual ones.
This works in SE mode because the virtual and physical addresses specified for
segments are the same. In Alpha, the LoadAddrMask is still necessary because
the virtual and physical addresses are the same and apparently rely on the
super page mechanism. All of the regressions pass.

Loader: Load all segments of an elf, rather than just the "text" and "data".

Loader: Error if a TLS section is found in the binary.

Get rid of GNU libelf and its autoconf nastiness and replace
it with FreeBSD's implementation

Get X86 to load an elf and start a process for it.

src/arch/x86/SConscript:
Add in process source files.
src/arch/x86/isa_traits.hh:
Replace magic constant numbers with the x86 register names.
src/arch/x86/miscregfile.cc:
Make clear the miscreg file succeed. There aren't any misc regs, so clearing them is very easy.
src/arch/x86/process.hh:
An X86 process class.
src/base/loader/elf_object.cc:
Add in code to recognize x86 as an architecture.
src/base/traceflags.py:
Add an x86 traceflag
src/sim/process.cc:
Add in code to create an x86 process.
src/arch/x86/intregs.hh:
A file which declares names for the integer register indices.
src/arch/x86/linux/linux.cc:
src/arch/x86/linux/linux.hh:
A very simple translation of SPARC's linux.cc and linux.hh. It's probably not correct for x86, but it might not be correct for SPARC either.
src/arch/x86/linux/process.cc:
src/arch/x86/linux/process.hh:
An x86 linux process. The syscall table is split out into it's own file.
src/arch/x86/linux/syscalls.cc:
The x86 Linux syscall table and the uname function.
src/arch/x86/process.cc:
The x86 process base class.
tests/test-progs/hello/bin/x86/linux/hello:
An x86 hello world test binary.

Make trap instructions always generate TrapInstruction Fault objects which call into the Process object to handle system calls. Refactored the Process objects, and move the handler code into it's own file, and add some syscalls which are used in a natively compiled hello world. Software traps with trap number 3 (not syscall number 3) are supposed to cause the register windows to be flushed but are ignored right now. Finally, made uname for SPARC report a 2.6.12 kernel which is what m22-018.pool happens to be running.

we decided to check for .interp instead of .dynamic

check if an executable is dynamic and die if it is
Only implemented for ELf. Someone might want to implement it for ecoff and some point

src/base/loader/elf_object.cc:
src/base/loader/elf_object.hh:
src/base/loader/object_file.cc:
src/base/loader/object_file.hh:
add a function to check if an executable is dynamic
src/sim/process.cc:
check if an executable is dynamic and die if it is

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

Added code to support setting up all of the auxillieary vectors configured by the sparc linux elf loader.

src/arch/sparc/process.cc:
All of the auxilliary vectors are now set like they are in the linux elf loader. This code should probably be moved to arch/sparc/linux/process.cc somehow.

Updated Authors from bk prs info

Clean up libelf handling.

SConstruct:
Clean up libelf handling. Required better handling of
per-build-root stuff in general (though libelf is the
only thing in that category currently).
src/SConscript:
No libelf-specific stuff in here anymore.
src/base/loader/elf_object.cc:
Just need to include gelf.h... it includes libelf.h.

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.