Re: [PATCH v1 4/6] objtool/LoongArch: Enable orc to be built

[Tiezhu Yang]

On 07/25/2023 07:51 PM, Peter Zijlstra wrote:
> On Tue, Jul 25, 2023 at 04:15:08PM +0800, Tiezhu Yang wrote:
>
> Previous Changelog had:
>
> > Define update_cfi_state() as a weak function which may be overwritten
> > by the arch-specific implementation.
>
> And then this patch does:
>
> > +int update_cfi_state(struct instruction *insn,
> > +		     struct instruction *next_insn,
> > +		     struct cfi_state *cfi, struct stack_op *op)
> > +{
> > +	struct cfi_reg *cfa = &cfi->cfa;
> > +	struct cfi_reg *regs = cfi->regs;

...

> > +	default:
> > +		WARN_FUNC("unknown stack-related instruction", insn->sec, insn->offset);
> > +		return -1;
> > +	}
> > +
> > +	return 0;
> > +}
>
> Why ?!? what is the actual irreconcilable difference?

I went in deeper to analysis the code and did more test,
the conclusion is that there is no need to define the
arch-specific update_cfi_state(), although it seems simpler
than the generic update_cfi_state(), the generic function
can handle all the cases and works well.

> If you want us to review this, you'll have to explain things.

I will drop the related changes in the next version, thank you.

Thanks,
Tiezhu