[PATCH v3 2/2] gdb: Support stepping out from signal handler on riscv*-linux

[Pedro Alves]

On 2021-07-07 1:30 a.m., Lancelot SIX via Gdb-patches wrote:

> After this patch, all tests in gdb.base/sigstep.exp pass.
> 
> Build and tested on riscv64-linux-gnu.

Thanks.  Other than a couple easyfix issues below, this LGTM.

>  #include "gdbarch.h"
>  
> +/* The following value is derived from __NR_rt_sigreturn in
> +   <include/uapi/asm-generic/unistd.h> from the linux source tree.  */

s/linux/Linux/

>  
>        /* Other instructions are not interesting during the prologue scan, and
>  	 are ignored.  */
> @@ -1711,6 +1713,8 @@ riscv_insn::decode (struct gdbarch *gdbarch, CORE_ADDR pc)
>  	decode_r_type_insn (SC, ival);
>        else if (is_sc_d_insn (ival))
>  	decode_r_type_insn (SC, ival);
> +      else if (is_ecall_insn (ival))
> +	decode_i_type_insn (ECALL, ival);

OOC, where are these is_FOO_insn functions declared/defined?

> @@ -3826,6 +3831,11 @@ riscv_next_pc (struct regcache *regcache, CORE_ADDR pc)
>        if (src1 >= src2)
>  	next_pc = pc + insn.imm_signed ();
>      }
> +  else if (insn.opcode () == riscv_insn::ECALL)
> +    {
> +      if (tdep->syscall_next_pc != nullptr)
> +	next_pc = tdep->syscall_next_pc (get_current_frame ());


	else
	  next_pc += 4;

?

> +    }
>  
>    return next_pc;
>  }

>  
> +  /* Return the expected next PC if FRAME is stopped at a syscall
> +     instruction.  */
> +  CORE_ADDR (*syscall_next_pc) (struct frame_info *frame);

"if" -> "assuming" ?