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2017-11-07alpha,arm,mips,power,riscv,sparc,x86: Merge exec decl templates.Gabe Black
In the ISA instruction definitions, some classes were declared with execute, etc., functions outside of the main template because they had CPU specific signatures and would need to be duplicated with each CPU plugged into them. Now that the instructions always just use an ExecContext, there's no reason for those templates to be separate. This change folds those templates together. Change-Id: I13bda247d3d1cc07c0ea06968e48aa5b4aace7fa Reviewed-on: https://gem5-review.googlesource.com/5401 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Alec Roelke <ar4jc@virginia.edu> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2017-11-02alpha,arm,mips,power,riscv,sparc,x86,isa: De-specialize ExecContexts.Gabe Black
The ISA parser used to generate different copies of exec functions for each exec context class a particular CPU wanted to use. That's since been changed so that those functions take a pointer to the base ExecContext, so the code which would generate those extra functions can be removed, and some functions which used to be templated on an ExecContext subclass can be untemplated, or minimally less templated. Now that some functions aren't going to be instantiated multiple times with different signatures, there are also opportunities to collapse templates and make many instruction definitions simpler within the parser. Since those changes will be less mechanical, they're left for later changes and will probably be done in smaller increments. Change-Id: I0015307bb02dfb9c60380b56d2a820f12169ebea Reviewed-on: https://gem5-review.googlesource.com/5381 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2017-10-17scons: Stop generating inc.d in the isa parser.Gabe Black
Generating dependency/build product information in the isa parser breaks scons idea of how a build is supposed to work. Arm twisting it into working forced a lot of false dependencies which slowed down the build. Change-Id: Iadee8c930fd7c80136d200d69870df7672a6b3ca Reviewed-on: https://gem5-review.googlesource.com/5081 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Gabe Black <gabeblack@google.com>
2017-10-13mem: Signal the local monitor when clearing the global monitorNikos Nikoleris
ARM systems require the coordination of the global and local monitors. When the system is run without caches the global monitor is implemented in the abstract memory object. This change adds a callback from the abstract memory that notifies the local monitor when the global monitor is cleared. Additionally, for ARM systems the local monitor signals the event register and wakes the thread context up. Subsequent wait-for-event (WFE) instructions will be immediately signaled. Change-Id: If6c038f3a6bea7239ba4258f07f39c7f9a30500b Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-on: https://gem5-review.googlesource.com/3760 Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
2017-09-11stats: Get rid of some kernel stats related cruft.Gabe Black
The kernel stat mechanism should really be refactored and moved somewhere else, but in the mean time there's some old cruft that can be cleared away. Change-Id: I21e725de590dda0d20bf3bc675bbe976c7b1bd86 Reviewed-on: https://gem5-review.googlesource.com/4600 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2017-07-17riscv: Define register index constants using literalsAlec Roelke
To make it clearer what the register indices are for the semantically meaningful registers defined by src/arch/riscv/registers.hh, the constants that were defined using other constants were changed to use the literal values of those constants. This also removes the need to use the M5_VAR_USED attribute. Change-Id: I7cccbe45d3d820deb5149a5925415735f6ae2e61 Reviewed-on: https://gem5-review.googlesource.com/4080 Reviewed-by: Gabe Black <gabeblack@google.com> Maintainer: Alec Roelke <ar4jc@virginia.edu>
2017-07-14riscv: Disambiguate between the C and C++ versions of isnan and isinf.Gabe Black
When both the C and C++ versions are visible, the compiler will complain that it doesn't know which one to use. By specifying the std namespace, it will know to use the C++ version. Change-Id: Ie1bbe1d95eadbad9644b4915c21f924d7d5c0b22 Reviewed-on: https://gem5-review.googlesource.com/4060 Reviewed-by: Alec Roelke <ar4jc@virginia.edu> Maintainer: Alec Roelke <ar4jc@virginia.edu>
2017-07-14riscv: Fix bugs with RISC-V decoder and detailed CPUsAlec Roelke
This patch fixes some bugs that were missed with the changes to the decoder that enabled compatibility with compressed instructions. In order to accommodate speculation with variable instruction widths, a few assertions in decoder had to be changed to returning faults as the specification describes should normally happen. The rest of these assertions will be changed in a later patch. [Remove commented-out debugging line and add clarifying comment to registerName in utility.hh.] Change-Id: I3f333008430d4a905cb59547a3513f5149b43b95 Reviewed-on: https://gem5-review.googlesource.com/4041 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Alec Roelke <ar4jc@virginia.edu>
2017-07-14riscv: Add unused attribute to some registers.hh constantsAlec Roelke
Three of the constants defined in arch/riscv/registers.hh (ReturnValueReg, SyscallNumReg, and SyscallPseudoReturnReg) may cause the compiler to warn that they are unused, which results in an error. This patch adds M5_VAR_USED attributes to them to stop this. Change-Id: Ie6389a55e8ffb3d003a47d02e76bdf9fb5219457 Reviewed-on: https://gem5-review.googlesource.com/4040 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Alec Roelke <ar4jc@virginia.edu>
2017-07-11arch-riscv: Add support for compressed extension RV64CAlec Roelke
This patch adds compatibility with the 64-bit compressed extension to the RISC-V ISA, RV64C. Current versions of the toolchain may use compressed instructions in glibc by default, which can only be overridden by recompiling the entire toolchain (simply adding "-march=rv64g" or "-march=rv64imafd" when compiling a binary is not sufficient to use uncompressed instructions in glibc functions in the binary). [Update diassembly generation for new RegId type.] [Rebase onto master.] Change-Id: Ifd5a5ea746704ce7e1b111442c3eb84c509a98b4 Reviewed-on: https://gem5-review.googlesource.com/3860 Reviewed-by: Alec Roelke <ar4jc@virginia.edu> Maintainer: Alec Roelke <ar4jc@virginia.edu>
2017-07-11arch-riscv: Restructure ISA descriptionAlec Roelke
This patch restructures the RISC-V ISA description to use fewer classes and improve its ability to be extended with nonstandard extensions in the future. It also cleans up the disassembly for some of the CSR and system instructions by removing source and destination registers for instructions that don't have any. [Fix class UImmOp to have an "imm" member rather than "uimm".] [Update disassembly generation for new RegId class.] Change-Id: Iec1c782020126e5e8e73460b84e31c7b5a5971d9 Reviewed-on: https://gem5-review.googlesource.com/3800 Maintainer: Alec Roelke <ar4jc@virginia.edu> Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
2017-07-05cpu: Added interface for vector reg fileRekai Gonzalez-Alberquilla
This patch adds some more functionality to the cpu model and the arch to interface with the vector register file. This change consists mainly of augmenting ThreadContexts and ExecContexts with calls to get/set full vectors, underlying microarchitectural elements or lanes. Those are meant to interface with the vector register file. All classes that implement this interface also get an appropriate implementation. This requires implementing the vector register file for the different models using the VecRegContainer class. This change set also updates the Result abstraction to contemplate the possibility of having a vector as result. The changes also affect how the remote_gdb connection works. There are some (nasty) side effects, such as the need to define dummy numPhysVecRegs parameter values for architectures that do not implement vector extensions. Nathanael Premillieu's work with an increasing number of fixes and improvements of mine. Change-Id: Iee65f4e8b03abfe1e94e6940a51b68d0977fd5bb Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> [ Fix RISCV build issues and CC reg free list initialisation ] Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-on: https://gem5-review.googlesource.com/2705
2017-07-05cpu: Simplify the rename interface and use RegIdRekai Gonzalez-Alberquilla
With the hierarchical RegId there are a lot of functions that are redundant now. The idea behind the simplification is that instead of having the regId, telling which kind of register read/write/rename/lookup/etc. and then the function panic_if'ing if the regId is not of the appropriate type, we provide an interface that decides what kind of register to read depending on the register type of the given regId. Change-Id: I7d52e9e21fc01205ae365d86921a4ceb67a57178 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> [ Fix RISCV build issues ] Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-on: https://gem5-review.googlesource.com/2702
2017-07-05arch, cpu: Architectural Register structural indexingNathanael Premillieu
Replace the unified register mapping with a structure associating a class and an index. It is now much easier to know which class of register the index is referring to. Also, when adding a new class there is no need to modify existing ones. Change-Id: I55b3ac80763702aa2cd3ed2cbff0a75ef7620373 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> [ Fix RISCV build issues ] Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-on: https://gem5-review.googlesource.com/2700
2017-05-23arch-riscv: Fix bad stack initializationAlec Roelke
This patch fixes a problem with RISC-V initial stack setup in SE mode where the AT_RANDOM aux vector value contains an address that is too close to the top of the stack and doesn't fit the required 16 bytes. To fix this, the program header table was added to the top of the stack just like the RISC-V proxy kernel does. Change-Id: I814562e060ff041cd0d7a7c54c3685645bd325a3 Reviewed-on: https://gem5-review.googlesource.com/3401 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Brandon Potter <Brandon.Potter@amd.com> Maintainer: Alec Roelke <ar4jc@virginia.edu>
2017-05-18base: Refactor the GDB code.Gabe Black
The new version modularizes the implementation of the various commands, gets rid of dynamic allocation of the register cache, fixes some small style problems, and uses exceptions to simplify error handling internal to the GDB stub. Change-Id: Iff3548373ce4adfb99106a810f5713b769df89b2 Reviewed-on: https://gem5-review.googlesource.com/3280 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Boris Shingarov <shingarov@gmail.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2017-05-18syscall_emul, riscv: add override keyword to RISCV Process classBrandon Potter
Change-Id: I2a146ae57aac3787389997961208474a97e7c155 Reviewed-on: https://gem5-review.googlesource.com/3360 Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Alec Roelke <ar4jc@virginia.edu>
2017-04-11riscv: Fix crashes with large or frequent mmapsAlec Roelke
This patch fixes a bug where increasing the mmap region too much causes it to run into already-allocated memory, which causes gem5 to fail an assertion. Previously, the stack was incorrectly set up such that the end of the mmap region and the top of the stack were the same address and both would grow downward. With this patch, the top of the stack has been separated from the end of mmap and moved up, and the mmap region now grows upward instead of downward. [Rebase to master branch and remove dependencies.] Change-Id: I7271ff478fff2994f918bc5003a6139b9ba6a520 Reviewed-on: https://gem5-review.googlesource.com/2680 Maintainer: Alec Roelke <ar4jc@virginia.edu> Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
2017-04-05riscv: fix Linux problems with LR and SC opsAlec Roelke
Some of the functions in the Linux toolchain that allocate memory make use of paired LR and SC instructions, which didn't work properly for that toolchain. This patch fixes that so attempting to use those functions doesn't cause an endless loop of failed SC instructions. Change-Id: If27696323dd6229a0277818e3744fbdf7180fca7 Reviewed-on: https://gem5-review.googlesource.com/2340 Maintainer: Alec Roelke <ar4jc@virginia.edu> Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
2017-04-05riscv: fix compatibility with Linux toolchainAlec Roelke
Previously, RISC-V in gem5 only supported RISC-V's Newlib toolchain (riscv64-unknown-elf-*) due to incorrect assumptions made in the initial setup of the user stack in SE mode. This patch fixes that by referring to the RISC-V proxy kernel code (https://github.com/riscv/riscv-pk) and setting up the stack according to how it does it. Now binaries compiled using the Linux toolchain (riscv64-unknown-linux-gnu-*) will run as well. [Update for recent changes to MemState to add accessors and mutators to get its members.] Change-Id: I6d2c486df7688efe3df54273e9aa0fd686851285 Reviewed-on: https://gem5-review.googlesource.com/2305 Maintainer: Alec Roelke <ar4jc@virginia.edu> Reviewed-by: Brandon Potter <Brandon.Potter@amd.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
2017-04-05riscv: add remote gdb supportAlec Roelke
This patch adds support for debugging with remote GDB to RISC-V. Using GDB compiled with the RISC-V GNU toolchain, it is possible to pause and continue execution, view debugging information, etc. As with the rest of RISC-V, this does not support full-system mode. Change-Id: I2d3a8be614725e1be4b4c283f9fb678a0a30578d Reviewed-on: https://gem5-review.googlesource.com/2304 Maintainer: Alec Roelke <ar4jc@virginia.edu> Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
2017-04-05riscv: fix error on memory op address overflowAlec Roelke
Previously, if a memory operation referenced an address that caused the data to wrap around to the beginning of the memory (such as -1 or 0xFFFFFFFFFFFFFFFF), an assert would fail during address translation and gem5 would crash. This patch fixes that by checking for such a case in RISC-V's TLB code and returning a fault from translateData if that would happen. Because RISC-V does support unaligned memory accesses, no checking is performed to make sure that an access doesn't cross a cache line. [Update creation of page table fault to use make_shared.] [Add comment explaining the change and assertion that the memory request isn't zero size.] Change-Id: I7b8ef9a5838f30184dbdbd0c7c1655e1c04a9410 Reviewed-on: https://gem5-review.googlesource.com/2345 Maintainer: Alec Roelke <ar4jc@virginia.edu> Reviewed-by: Brandon Potter <Brandon.Potter@amd.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
2017-04-05riscv: enable unaligned memory accessesAlec Roelke
Sometimes an ld instruction will be split across a cache boundary. Previously RISC-V was set to not allow this. This patch fixes that. Change-Id: I8bc8ea6d67f65a9b3662e14c4037f4224799d20f Reviewed-on: https://gem5-review.googlesource.com/2341 Maintainer: Alec Roelke <ar4jc@virginia.edu> Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
2017-03-09syscall-emul: Rewrite system call exit codeBrandon Potter
The changeset does a major refactor on the exit, exit_group, and futex system calls regarding exit functionality. A FutexMap class and related structures are added into a new file. This increases code clarity by encapsulating the futex operations and the futex state into an object. Several exit conditions were added to allow the simulator to end processes under certain conditions. Also, the simulation only exits now when all processes have finished executing. Change-Id: I1ee244caa9b5586fe7375e5b9b50fd3959b9655e Reviewed-on: https://gem5-review.googlesource.com/2269 Maintainer: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
2017-03-09syscall-emul: Move memState into its own fileBrandon Potter
The Process class is full of implementation details and structures related to SE Mode. This changeset factors out an internal class from Process and moves it into a separate file. The purpose behind doing this is to clean up the code and make it a bit more modular. Change-Id: Ic6941a1657751e8d51d5b6b1dcc04f1195884280 Reviewed-on: https://gem5-review.googlesource.com/2263 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2017-02-27syscall_emul: [PATCH 15/22] add clone/execve for threading and multiprocess ↵Brandon Potter
simulations Modifies the clone system call and adds execve system call. Requires allowing processes to steal thread contexts from other processes in the same system object and the ability to detach pieces of process state (such as MemState) to allow dynamic sharing.
2015-07-20syscall_emul: [patch 13/22] add system call retry capabilityBrandon Potter
This changeset adds functionality that allows system calls to retry without affecting thread context state such as the program counter or register values for the associated thread context (when system calls return with a retry fault). This functionality is needed to solve problems with blocking system calls in multi-process or multi-threaded simulations where information is passed between processes/threads. Blocking system calls can cause deadlock because the simulator itself is single threaded. There is only a single thread servicing the event queue which can cause deadlock if the thread hits a blocking system call instruction. To illustrate the problem, consider two processes using the producer/consumer sharing model. The processes can use file descriptors and the read and write calls to pass information to one another. If the consumer calls the blocking read system call before the producer has produced anything, the call will block the event queue (while executing the system call instruction) and deadlock the simulation. The solution implemented in this changeset is to recognize that the system calls will block and then generate a special retry fault. The fault will be sent back up through the function call chain until it is exposed to the cpu model's pipeline where the fault becomes visible. The fault will trigger the cpu model to replay the instruction at a future tick where the call has a chance to succeed without actually going into a blocking state. In subsequent patches, we recognize that a syscall will block by calling a non-blocking poll (from inside the system call implementation) and checking for events. When events show up during the poll, it signifies that the call would not have blocked and the syscall is allowed to proceed (calling an underlying host system call if necessary). If no events are returned from the poll, we generate the fault and try the instruction for the thread context at a distant tick. Note that retrying every tick is not efficient. As an aside, the simulator has some multi-threading support for the event queue, but it is not used by default and needs work. Even if the event queue was completely multi-threaded, meaning that there is a hardware thread on the host servicing a single simulator thread contexts with a 1:1 mapping between them, it's still possible to run into deadlock due to the event queue barriers on quantum boundaries. The solution of replaying at a later tick is the simplest solution and solves the problem generally.
2016-11-09syscall_emul: [patch 8/22] refactor process classBrandon Potter
Moves aux_vector into its own .hh and .cc files just to get it out of the already crowded Process files. Arguably, it could stay there, but it's probably better just to move it and give it files. The changeset looks ugly around the Process header file, but the goal here is to move methods and members around so that they're not defined randomly throughout the entire header file. I expect this is likely one of the reasons why I several unused variables related to this class. So, the methods are declared first followed by members. I've tried to aggregate them together so that similar entries reside near one another. There are other changes coming to this code so this is by no means the final product.
2016-11-09syscall_emul: [patch 5/22] remove LiveProcess class and use Process insteadBrandon Potter
The EIOProcess class was removed recently and it was the only other class which derived from Process. Since every Process invocation is also a LiveProcess invocation, it makes sense to simplify the organization by combining the fields from LiveProcess into Process.
2017-01-27riscv: Fix crash when syscall argument reg index is too highAlec Roelke
By default, doSyscall gets the values of six registers to be used for system call arguments. RISC-V, by convention, only has four. Because RISC-V's implementation of these indices is as arrays of integers rather than as base indices plus offsets, trying to get the fifth argument register's value will cause a crash. This patch fixes that by returning 0 for any index higher than 3. Signed-off-by: Jason Lowe-Power <jason@lowepower.com>
2016-11-09style: [patch 3/22] reduce include dependencies in some headersBrandon Potter
Used cppclean to help identify useless includes and removed them. This involved erroneously included headers, but also cases where forward declarations could have been used rather than a full include.
2016-11-09syscall_emul: [patch 2/22] move SyscallDesc into its own .hh and .ccBrandon Potter
The class was crammed into syscall_emul.hh which has tons of forward declarations and template definitions. To clean it up a bit, moved the class into separate files and commented the class with doxygen style comments. Also, provided some encapsulation by adding some accessors and a mutator. The syscallreturn.hh file was renamed syscall_return.hh to make it consistent with other similarly named files in the src/sim directory. The DPRINTF_SYSCALL macro was moved into its own header file with the include the Base and Verbose flags as well. --HG-- rename : src/sim/syscallreturn.hh => src/sim/syscall_return.hh
2016-11-30riscv: [Patch 7/5] Corrected LRSC semanticsAlec Roelke
RISC-V makes use of load-reserved and store-conditional instructions to enable creation of lock-free concurrent data manipulation as well as ACQUIRE and RELEASE semantics for memory ordering of LR, SC, and AMO instructions (the latter of which do not follow LR/SC semantics). This patch is a correction to patch 4, which added these instructions to the implementation of RISC-V. It modifies locked_mem.hh and the implementations of lr.w, sc.w, lr.d, and sc.d to apply the proper gem5 flags and return the proper values. An important difference between gem5's LLSC semantics and RISC-V's LR/SC ones, beyond the name, is that gem5 uses 0 to indicate failure and 1 to indicate success, while RISC-V is the opposite. Strictly speaking, RISC-V uses 0 to indicate success and nonzero to indicate failure where the value would indicate the error, but currently only 1 is reserved as a failure code by the ISA reference. This is the seventh patch in the series which originally consisted of five patches that added the RISC-V ISA to gem5. The original five patches added all of the instructions and added support for more detailed CPU models and the sixth patch corrected the implementations of Linux constants and structs. There will be an eighth patch that adds some regression tests for the instructions. [Removed some commented-out code from locked_mem.hh.] Signed-off by: Alec Roelke Signed-off by: Jason Lowe-Power <jason@lowepower.com>
2016-11-30riscv: [Patch 6/5] Improve Linux emulation for RISC-VAlec Roelke
This is an add-on patch for the original series that implemented RISC-V that improves the implementation of Linux emulation for SE mode. Basically it cleans up linux/linux.hh by removing constants that haven't been defined for the RISC-V Linux proxy kernel and rearranging the stat struct so it aligns with RISC-V's implementation of it. It also adds placeholders for system calls that have been given numbers in RISC-V but haven't been given implementations yet. These system calls are as follows: - readlinkat - sigprocmask - ioctl - clock_gettime - getrusage - getrlimit - setrlimit The first five patches implemented RISC-V with the base ISA and multiply, floating point, and atomic extensions and added support for detailed CPU models with memory timing. [Fixed incompatibility with changes made from patch 1.] Signed-off by: Alec Roelke Signed-off by: Jason Lowe-Power <jason@lowepower.com>
2016-11-30riscv: [Patch 5/5] Added missing support for timing CPU modelsAlec Roelke
Last of five patches adding RISC-V to GEM5. This patch adds support for timing, minor, and detailed CPU models that was missing in the last four, which basically consists of handling timing-mode memory accesses and telling the minor and detailed models what a no-op instruction should be (addi zero, zero, 0). Patches 1-4 introduced RISC-V and implemented the base instruction set, RV64I, and added the multiply, floating point, and atomic memory extensions, RV64MAFD. [Fixed compatibility with edit from patch 1.] [Fixed compatibility with hg copy edit from patch 1.] [Fixed some style errors in locked_mem.hh.] Signed-off by: Alec Roelke Signed-off by: Jason Lowe-Power <jason@lowepower.com>
2016-11-30riscv: [Patch 4/5] Added RISC-V atomic memory extension RV64AAlec Roelke
Fourth of five patches adding RISC-V to GEM5. This patch adds the RV64A extension, which includes atomic memory instructions. These instructions atomically read a value from memory, modify it with a value contained in a source register, and store the original memory value in the destination register and modified value back into memory. Because this requires two memory accesses and GEM5 does not support two timing memory accesses in a single instruction, each of these instructions is split into two micro- ops: A "load" micro-op, which reads the memory, and a "store" micro-op, which modifies and writes it back. Each atomic memory instruction also has two bits that acquire and release a lock on its memory location. Additionally, there are atomic load and store instructions that only either load or store, but not both, and can acquire or release memory locks. Note that because the current implementation of RISC-V only supports one core and one thread, it doesn't make sense to make use of AMO instructions. However, they do form a standard extension of the RISC-V ISA, so they are included mostly as a placeholder for when multithreaded execution is implemented. As a result, any tests for their correctness in a future patch may be abbreviated. Patch 1 introduced RISC-V and implemented the base instruction set, RV64I; patch 2 implemented the integer multiply extension, RV64M; and patch 3 implemented the single- and double-precision floating point extensions, RV64FD. Patch 5 will add support for timing, minor, and detailed CPU models that isn't present in patches 1-4. [Added missing file amo.isa] [Replaced information removed from initial patch that was missed during division into multiple patches.] [Fixed some minor formatting issues.] [Fixed oversight where LR and SC didn't have both AQ and RL flags.] Signed-off by: Alec Roelke Signed-off by: Jason Lowe-Power <jason@lowepower.com>
2016-11-30riscv: [Patch 3/5] Added RISCV floating point extensions RV64FDAlec Roelke
Third of five patches adding RISC-V to GEM5. This patch adds the RV64FD extensions, which include single- and double-precision floating point instructions. Patch 1 introduced RISC-V and implemented the base instruction set, RV64I and patch 2 implemented the integer multiply extension, RV64M. 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. [Fixed exception handling in floating-point instructions to conform better to IEEE-754 2008 standard and behavior of the Chisel-generated RISC-V simulator.] [Fixed style errors in decoder.isa.] [Fixed some fuzz caused by modifying a previous patch.] Signed-off by: Alec Roelke Signed-off by: Jason Lowe-Power <jason@lowepower.com>
2016-11-30riscv: [Patch 2/5] Added RISC-V multiply extension RV64MAlec Roelke
Second of five patches adding RISC-V to GEM5. This patch adds the RV64M extension, which includes integer multiply and divide instructions. Patch 1 introduced RISC-V and implemented the base instruction set, RV64I. Patch 3 will implement the floating point 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. [Added mulw instruction that was missed when dividing changes among patches.] Signed-off by: Alec Roelke Signed-off by: Jason Lowe-Power <jason@lowepower.com>
2016-11-30arch: [Patch 1/5] Added RISC-V base instruction set RV64IAlec Roelke
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>