Hi Alistair, Phil,
well, I'm trying to keep the thing alive, checking from time to time that
the current QEMU still runs the 128-bit tests that I have, and on which
I continue (slowly) to do stuffs.
I hope this can stay upstream for experimental/research purposes, but the
128-bit riscv community is, I follow you on that, scarce for now.
So, your call.
Cheers,
Frédéric
Le 04/04/2025 à 05:26, Alistair Francis a écrit :
On Sat, Mar 22, 2025 at 1:09 AM Philippe Mathieu-Daudé
<phi...@linaro.org> wrote:
Hi,
On 6/1/22 22:00, Frédéric Pétrot wrote:
This series of patches provides partial 128-bit support for the riscv
target architecture, namely RVI and RVM, with minimal csr support.
Frédéric Pétrot (18):
exec/memop: Adding signedness to quad definitions
exec/memop: Adding signed quad and octo defines
qemu/int128: addition of div/rem 128-bit operations
target/riscv: additional macros to check instruction support
target/riscv: separation of bitwise logic and arithmetic helpers
target/riscv: array for the 64 upper bits of 128-bit registers
target/riscv: setup everything for rv64 to support rv128 execution
I see this series has been merged as commit afe33262585, with
332dab68785b describing:
This patch adds the support of the '-cpu rv128' option to
qemu-system-riscv64 so that we can indicate that we want to
run rv128 executables.
Still, there is no support for 128-bit insns at that stage
so qemu fails miserably (as expected) if launched with this
option.
Is this code tested? 3 years passed so I wonder about possible
code bitrot here.
From memory at the time there was some momentum for RV128. So this was
merged with the expectation that it would continue to improve.
That doesn't seem to have happened, either software or spec wise though.
(I reached this code by looking at targets not supporting MTTCG).
I'm happy to remove the CPU if it's blocking you, it's experimental so
it doesn't need to be deprecated or anything fancy.
Alistair
target/riscv: moving some insns close to similar insns
target/riscv: accessors to registers upper part and 128-bit load/store
target/riscv: support for 128-bit bitwise instructions
target/riscv: support for 128-bit U-type instructions
target/riscv: support for 128-bit shift instructions
target/riscv: support for 128-bit arithmetic instructions
target/riscv: support for 128-bit M extension
target/riscv: adding high part of some csrs
target/riscv: helper functions to wrap calls to 128-bit csr insns
target/riscv: modification of the trans_csrxx for 128-bit support
target/riscv: actual functions to realize crs 128-bit insns
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