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path: root/src/arch/riscv/isa_traits.hh
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2018-01-10alpha,arm,mips,power,riscv,sparc,x86,cpu: Get rid of ISA_HAS_DELAY_SLOT.Gabe Black
This constant is, first, a #define, and second only used in one place. In that one place, it appears that the code it guards is no longer necessary in general. It was originally written to avoid refetching a block of data that you're still in, even if you've moved slightly farther in it because you're skipping the next instruction due to an annulled branch delay slot. In reality however, in SPARC, the one ISA I'm aware of which has this sort of branching behavior, the PC state object will correctly determine that no branch is happening in these cases. Code lower down in the loop will then recompute where fetching should continue based on the next PC, automatically skipping the annulled branch slot without misinterpretting the gap as a branch. This change therefore also removes this block of code. Change-Id: I820ebc9df10aeb4fcb69c12f6a784e9ec616743c Reviewed-on: https://gem5-review.googlesource.com/6821 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2017-12-23alpha,arm,mips,power,riscv,sparc,x86: Get rid of TheISA::NoopMachInst.Gabe Black
It's no longer used. Change-Id: I4a71bcb214f1bb186b92ef50841eca635e6701c5 Reviewed-on: https://gem5-review.googlesource.com/6826 Reviewed-by: Gabe Black <gabeblack@google.com> Maintainer: Gabe Black <gabeblack@google.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>
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>
2016-11-30arch: [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>