mbox series

[v5,0/6] Pointer Masking update for Zjpm v0.8

Message ID 20240129192207.2946870-1-me@deliversmonkey.space (mailing list archive)
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Series Pointer Masking update for Zjpm v0.8 | expand

Message

Alexey Baturo Jan. 29, 2024, 7:22 p.m. UTC
From: Alexey Baturo <baturo.alexey@gmail.com>

Hi,

This patch series targets Zjpm v0.8 extension.
The spec itself could be found here: https://github.com/riscv/riscv-j-extension/blob/8088461d8d66a7676872b61c908cbeb7cf5c5d1d/zjpm-spec.pdf
This patch series is updated after the suggested comments:
- add "x-" to the extension names to indicate experimental

[v4]:
Patch series updated after the suggested comments:
- removed J-letter extension as it's unused
- renamed and fixed function to detect if address should be sign-extended
- zeroed unused context variables and moved computation logic to another patch
- bumped pointer masking version_id and minimum_version_id by 1

Thanks

[v3]:
There patches are updated after Richard's comments:
- moved new tb flags to the end
- used tcg_gen_(s)extract to get the final address
- properly handle CONFIG_USER_ONLY

Thanks

[v2]:
As per Richard's suggestion I made pmm field part of tb_flags.
It allowed to get rid of global variable to store pmlen.
Also it allowed to simplify all the machinery around it.

Thanks

[v1]:
Hi all,

It looks like Zjpm v0.8 is almost frozen and we don't expect it change drastically anymore.
Compared to the original implementation with explicit base and mask CSRs, we now only have
several fixed options for number of masked bits which are set using existing CSRs.
The changes have been tested with handwritten assembly tests and LLVM HWASAN
test suite.

Thanks

Alexey Baturo (6):
  target/riscv: Remove obsolete pointer masking extension code.
  target/riscv: Add new CSR fields for S{sn,mn,m}pm extensions as part
    of Zjpm v0.8
  target/riscv: Add helper functions to calculate current number of
    masked bits for pointer masking
  target/riscv: Add pointer masking tb flags
  target/riscv: Update address modify functions to take into account
    pointer masking
  target/riscv: Enable updates for pointer masking variables and thus
    enable pointer masking extension

 target/riscv/cpu.c           |  22 ++-
 target/riscv/cpu.h           |  46 +++--
 target/riscv/cpu_bits.h      |  90 +---------
 target/riscv/cpu_cfg.h       |   3 +
 target/riscv/cpu_helper.c    |  97 +++++-----
 target/riscv/csr.c           | 337 ++---------------------------------
 target/riscv/machine.c       |  20 +--
 target/riscv/pmp.c           |  13 +-
 target/riscv/pmp.h           |  11 +-
 target/riscv/tcg/tcg-cpu.c   |   5 +-
 target/riscv/translate.c     |  46 ++---
 target/riscv/vector_helper.c |  15 +-
 12 files changed, 158 insertions(+), 547 deletions(-)

Comments

Alistair Francis Feb. 1, 2024, 2:02 a.m. UTC | #1
On Tue, Jan 30, 2024 at 5:23 AM Alexey Baturo <baturo.alexey@gmail.com> wrote:
>
> From: Alexey Baturo <baturo.alexey@gmail.com>
>
> Hi,
>
> This patch series targets Zjpm v0.8 extension.
> The spec itself could be found here: https://github.com/riscv/riscv-j-extension/blob/8088461d8d66a7676872b61c908cbeb7cf5c5d1d/zjpm-spec.pdf
> This patch series is updated after the suggested comments:
> - add "x-" to the extension names to indicate experimental

Do you mind rebasing this on
https://github.com/alistair23/qemu/tree/riscv-to-apply.next ?

Alistair

>
> [v4]:
> Patch series updated after the suggested comments:
> - removed J-letter extension as it's unused
> - renamed and fixed function to detect if address should be sign-extended
> - zeroed unused context variables and moved computation logic to another patch
> - bumped pointer masking version_id and minimum_version_id by 1
>
> Thanks
>
> [v3]:
> There patches are updated after Richard's comments:
> - moved new tb flags to the end
> - used tcg_gen_(s)extract to get the final address
> - properly handle CONFIG_USER_ONLY
>
> Thanks
>
> [v2]:
> As per Richard's suggestion I made pmm field part of tb_flags.
> It allowed to get rid of global variable to store pmlen.
> Also it allowed to simplify all the machinery around it.
>
> Thanks
>
> [v1]:
> Hi all,
>
> It looks like Zjpm v0.8 is almost frozen and we don't expect it change drastically anymore.
> Compared to the original implementation with explicit base and mask CSRs, we now only have
> several fixed options for number of masked bits which are set using existing CSRs.
> The changes have been tested with handwritten assembly tests and LLVM HWASAN
> test suite.
>
> Thanks
>
> Alexey Baturo (6):
>   target/riscv: Remove obsolete pointer masking extension code.
>   target/riscv: Add new CSR fields for S{sn,mn,m}pm extensions as part
>     of Zjpm v0.8
>   target/riscv: Add helper functions to calculate current number of
>     masked bits for pointer masking
>   target/riscv: Add pointer masking tb flags
>   target/riscv: Update address modify functions to take into account
>     pointer masking
>   target/riscv: Enable updates for pointer masking variables and thus
>     enable pointer masking extension
>
>  target/riscv/cpu.c           |  22 ++-
>  target/riscv/cpu.h           |  46 +++--
>  target/riscv/cpu_bits.h      |  90 +---------
>  target/riscv/cpu_cfg.h       |   3 +
>  target/riscv/cpu_helper.c    |  97 +++++-----
>  target/riscv/csr.c           | 337 ++---------------------------------
>  target/riscv/machine.c       |  20 +--
>  target/riscv/pmp.c           |  13 +-
>  target/riscv/pmp.h           |  11 +-
>  target/riscv/tcg/tcg-cpu.c   |   5 +-
>  target/riscv/translate.c     |  46 ++---
>  target/riscv/vector_helper.c |  15 +-
>  12 files changed, 158 insertions(+), 547 deletions(-)
>
> --
> 2.34.1
>
>