Re: [PATCH-for-8.0 v3] target/arm: Fix non-TCG build failure by inlining pauth_ptr_mask()

[Peter Maydell]

On Tue, 28 Mar 2023 at 22:25, Philippe Mathieu-Daudé <philmd@linaro.org> wrote:
>
> aarch64_gdb_get_pauth_reg() -- although disabled since commit
> 5787d17a42 ("target/arm: Don't advertise aarch64-pauth.xml to
> gdb") is still compiled in. It calls pauth_ptr_mask() which is
> located in target/arm/tcg/pauth_helper.c, a TCG specific helper.
>
> To avoid a linking error when TCG is not enabled:
>
>   Undefined symbols for architecture arm64:
>     "_pauth_ptr_mask", referenced from:
>         _aarch64_gdb_get_pauth_reg in target_arm_gdbstub64.c.o
>   ld: symbol(s) not found for architecture arm64
>   clang: error: linker command failed with exit code 1 (use -v to see 
> invocation)
>
> - Inline pauth_ptr_mask() in aarch64_gdb_get_pauth_reg()
>   (this is the single user),
> - Rename pauth_ptr_mask_internal() as pauth_ptr_mask() and
>   inline it in "internals.h",
>
> Fixes: e995d5cce4 ("target/arm: Implement gdbstub pauth extension")
> Suggested-by: Richard Henderson <richard.henderson@linaro.org>
> Reviewed-by: Fabiano Rosas <farosas@suse.de>
> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
> Supersedes: <20230328133054.6553-1-philmd@linaro.org>
>
> Since v2:
> - Rebased (patch #1 merged)
> - Addressed rth's comments
> - Added R-b tags
> ---
>  target/arm/internals.h        | 16 +++++++---------
>  target/arm/gdbstub64.c        |  7 +++++--
>  target/arm/tcg/pauth_helper.c | 18 +-----------------
>  3 files changed, 13 insertions(+), 28 deletions(-)
>
> diff --git a/target/arm/internals.h b/target/arm/internals.h
> index 673519a24a..71f4c6d8a2 100644
> --- a/target/arm/internals.h
> +++ b/target/arm/internals.h
> @@ -1389,15 +1389,13 @@ int exception_target_el(CPUARMState *env);
>  bool arm_singlestep_active(CPUARMState *env);
>  bool arm_generate_debug_exceptions(CPUARMState *env);
>
> -/**
> - * pauth_ptr_mask:
> - * @env: cpu context
> - * @ptr: selects between TTBR0 and TTBR1
> - * @data: selects between TBI and TBID
> - *
> - * Return a mask of the bits of @ptr that contain the authentication code.
> - */
> -uint64_t pauth_ptr_mask(CPUARMState *env, uint64_t ptr, bool data);
> +static inline uint64_t pauth_ptr_mask(ARMVAParameters param)
> +{
> +    int bot_pac_bit = 64 - param.tsz;
> +    int top_pac_bit = 64 - 8 * param.tbi;
> +
> +    return MAKE_64BIT_MASK(bot_pac_bit, top_pac_bit - bot_pac_bit);
> +}

Any reason for deleting the doc comment ?

thanks
-- PMM