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This is an automatically generated e-mail. To reply, visit:
http://reviews.gem5.org/r/3629/
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(Updated Sept. 20, 2016, 2:54 a.m.)


Review request for Default.


Repository: gem5


Description (updated)
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Changeset 11650:1b6fe4ffa57d
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riscv: [Patch 4/5] Added RISC-V atomic memory extension RV64A

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: These have not actually been tested for atomicity yet because
multicore and multithreaded simulation has not been implemented. They do
work in single-threaded systems, however.

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]
Signed-off by: Alec Roelke


Diffs
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  src/arch/riscv/isa/bitfields.isa PRE-CREATION 
  src/arch/riscv/isa/decoder.isa PRE-CREATION 
  src/arch/riscv/isa/formats/amo.isa PRE-CREATION 
  src/arch/riscv/isa/formats/formats.isa PRE-CREATION 
  src/arch/riscv/isa/formats/mem.isa PRE-CREATION 
  src/arch/riscv/isa/main.isa PRE-CREATION 
  src/arch/riscv/isa/micro.isa PRE-CREATION 
  src/arch/riscv/isa/operands.isa PRE-CREATION 
  src/arch/riscv/types.hh PRE-CREATION 

Diff: http://reviews.gem5.org/r/3629/diff/


Testing
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Thanks,

Alec Roelke

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