Re: [PATCH v2 16/20] disas/nanomips: Replace exception handling

[Richard Henderson]

On 9/5/22 10:55, Milica Lazarevic wrote:
> Since there's no support for exception handling in C, the try-catch
> blocks have been deleted, and throw clauses are replaced. When a runtime
> error happens, we're printing out the error message. Disassembling of
> the current instruction interrupts. This behavior is achieved by adding
> sigsetjmp() to discard further disassembling after the error message
> prints and by adding the siglongjmp() function to imitate throwing an
> error. The goal was to maintain the same output as it was.
>
> Signed-off-by: Milica Lazarevic <milica.lazarevic@syrmia.com>
> ---
>   disas/nanomips.cpp | 126 ++++++++++++++++++++++-----------------------
>   1 file changed, 61 insertions(+), 65 deletions(-)
>
> diff --git a/disas/nanomips.cpp b/disas/nanomips.cpp
> index 5142f307fc..a8295ebfa8 100644
> --- a/disas/nanomips.cpp
> +++ b/disas/nanomips.cpp
> @@ -31,7 +31,6 @@
>   #include "disas/dis-asm.h"
>   
>   #include <string.h>
> -#include <stdexcept>
>   #include <stdio.h>
>   #include <stdarg.h>
>   
> @@ -134,10 +133,12 @@ static uint64 renumber_registers(uint64 index, uint64 *register_list,
>           return register_list[index];
>       }
>   
> -    throw std::runtime_error(img_format(
> -                   "Invalid register mapping index %" PRIu64
> -                   ", size of list = %zu",
> -                   index, register_list_size));
> +    g_autofree char *err = img_format(
> +                      "Invalid register mapping index %" PRIu64
> +                      ", size of list = %zu",
> +                      index, register_list_size);
> +    info->fprintf_func(info->stream, "%s", err);

There's no point passing the output of sprintf into fprintf like this.
Just fprintf in the first place.


> +                        disassembly_function dis_fn = table[i].disassembly;
> +                        if (dis_fn == 0) {
> +                            strcpy(dis,
> +                            "disassembler failure - bad table entry");
> +                            return -6;
> +                        }
> +                        type = table[i].type;
> +                        g_autofree char *dis_str = dis_fn(op_code, info);
> +                        strcpy(dis, dis_str);
> +                        return table[i].instructions_size;
> +                    } else {
> +                        strcpy(dis, "reserved instruction");
> +                        return -2;

Ought these errors use the same error path?


r~