Re: [PATCH 20/23] Add get_mcontext function for ARM AArch64 in bsd-user

[Richard Henderson <richard.henderson@linaro.org>]

On 6/17/24 11:58, Ajeet Singh wrote:
> From: Stacey Son <sson@FreeBSD.org>
> 
> function to retrieve machine context,it populates the provided
> target_mcontext_t structure with information from the CPUARMState
> registers
> 
> Signed-off-by: Stacey Son <sson@FreeBSD.org>
> Signed-off-by: Ajeet Singh <itachis@FreeBSD.org>
> Co-authored-by: Kyle Evans <kevans@FreeBSD.org>
> ---
>   bsd-user/aarch64/signal.c | 30 ++++++++++++++++++++++++++++++
>   1 file changed, 30 insertions(+)
> 
> diff --git a/bsd-user/aarch64/signal.c b/bsd-user/aarch64/signal.c
> index 98861f9ab3..ab3bf8558a 100644
> --- a/bsd-user/aarch64/signal.c
> +++ b/bsd-user/aarch64/signal.c
> @@ -51,3 +51,33 @@ abi_long set_sigtramp_args(CPUARMState *regs, int sig,
>   
>       return 0;
>   }
> +
> +/*
> + * Compare to get_mcontext() in arm64/arm64/machdep.c
> + * Assumes that the memory is locked if mcp points to user memory.
> + */
> +abi_long get_mcontext(CPUARMState *regs, target_mcontext_t *mcp, int flags)
> +{
> +    int err = 0, i;
> +    uint64_t *gr = mcp->mc_gpregs.gp_x;
> +
> +    mcp->mc_gpregs.gp_spsr = pstate_read(regs);
> +    if (flags & TARGET_MC_GET_CLEAR_RET) {
> +        gr[0] = 0UL;
> +        mcp->mc_gpregs.gp_spsr &= ~CPSR_C;
> +    } else {
> +        gr[0] = tswap64(regs->xregs[0]);
> +    }
> +
> +    for (i = 1; i < 30; i++) {
> +        gr[i] = tswap64(regs->xregs[i]);
> +    }
> +
> +    mcp->mc_gpregs.gp_sp = tswap64(regs->xregs[TARGET_REG_SP]);
> +    mcp->mc_gpregs.gp_lr = tswap64(regs->xregs[TARGET_REG_LR]);
> +    mcp->mc_gpregs.gp_elr = tswap64(regs->pc);
> +
> +    /* XXX FP? */

Reasonably simple.  See target_setup_fpsimd_record from linux-user/aarch64/signal.c.


r~