Question about MEPC and MBADADDR on JAL/JALR to misaligned addr.
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Rishiyur Nikhil
Feb 27, 2017, 11:42:39 AM2/27/17
to isa...@groups.riscv.org
The spec "User-Level ISA, Version 2.1" says (top of p.16):
The JAL and JALR instructions can generate a misaligned
instruction fetch exception if the target address is not aligned
to a four-byte boundary.
Question: what should be in MEPC and MBADADDR after this?
I'd guess that MEPC is the PC of the JAL/JALR instr
The JAL and JALR instructions can generate a misaligned
instruction fetch exception if the target address is not aligned
to a four-byte boundary.
Question: what should be in MEPC and MBADADDR after this?
I'd guess that MEPC is the PC of the JAL/JALR instr
(unlike an actual misaligned fetch where MEPC = misaligned fetch address)
and MBADADDR is the misaligned target address?
Nikhil
Samuel Falvo II
Feb 27, 2017, 1:04:45 PM2/27/17
to Rishiyur Nikhil, RISC-V ISA Dev
On Mon, Feb 27, 2017 at 8:42 AM, Rishiyur Nikhil <nik...@bluespec.com> wrote:
> Question: what should be in MEPC and MBADADDR after this?
MEPC will be the address of the JAL(R) instruction. MBADADDR will be
> Question: what should be in MEPC and MBADADDR after this?
the erroneous effective address.
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Samuel A. Falvo II
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