Re: [PATCH v7 4/8] Refactor arm_software_single_step to use regcache.

[Yao Qi <qiyaoltc@gmail.com>]

Antoine Tremblay <antoine.tremblay@ericsson.com> writes:

Hi Antoine,
Patch is OK to me, two nits below.

> diff --git a/gdb/arm-linux-tdep.c b/gdb/arm-linux-tdep.c
> index acb5701..eb4341c 100644
> --- a/gdb/arm-linux-tdep.c
> +++ b/gdb/arm-linux-tdep.c
> @@ -808,6 +808,68 @@ arm_linux_sigreturn_return_addr (struct frame_info *frame,
>    return 0;
>  }
>  
> +/* Calculate the offset from stack pointer of the pc register on the stack
> +   in the case of a sigreturn or sigreturn_rt syscall.  */
> +static int
> +arm_linux_sigreturn_next_pc_offset (unsigned long sp,
> +				    unsigned long sp_data,
> +				    unsigned long svc_number,
> +				    int is_sigreturn)
> +{
> +  /* Offset of R0 register.  */
> +  int r0_offset = 0;
> +  /* Offset of PC register.  */
> +  int pc_offset = 0;
> +
> +  if (is_sigreturn)
> +    {
> +      if (sp_data == ARM_NEW_SIGFRAME_MAGIC)
> +	r0_offset = ARM_UCONTEXT_SIGCONTEXT + ARM_SIGCONTEXT_R0;
> +      else
> +	r0_offset = ARM_SIGCONTEXT_R0;
> +    }
> +  else
> +    {
> +      if (sp_data == sp + ARM_OLD_RT_SIGFRAME_SIGINFO)
> +	r0_offset = ARM_OLD_RT_SIGFRAME_UCONTEXT + ARM_UCONTEXT_SIGCONTEXT
> +	  + ARM_SIGCONTEXT_R0;
> +      else
> +	r0_offset = ARM_NEW_RT_SIGFRAME_UCONTEXT + ARM_UCONTEXT_SIGCONTEXT
> +	  + ARM_SIGCONTEXT_R0;

Nit: we can write these long lines like this,

      if (sp_data == sp + ARM_OLD_RT_SIGFRAME_SIGINFO)
        r0_offset = ARM_OLD_RT_SIGFRAME_UCONTEXT;
      else
        r0_offset = ARM_NEW_RT_SIGFRAME_UCONTEXT;

      r0_offset += (ARM_UCONTEXT_SIGCONTEXT + ARM_SIGCONTEXT_R0);

>  
> -  arm_linux_sigreturn_return_addr (frame, svc_number, &return_addr, &is_thumb);
> +  if (is_syscall (gdbarch, "sigreturn", svc_number)
> +      || is_syscall (gdbarch, "rt_sigreturn", svc_number))
> +    next_pc = arm_linux_sigreturn_next_pc (regcache, svc_number);
>  
>    /* Addresses for calling Thumb functions have the bit 0 set.  */
>    if (is_thumb)
> -    return_addr |= 1;
> +    next_pc |= 1;

Nit: use MAKE_THUMB_ADDR.

-- 
Yao (齐尧)