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Date: Mon, 17 Oct 2022 00:31:09 +0900
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Subject: Re: [RFC PATCH 1/1] gdb/riscv: Cache per-BFD disassembler
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To: Tom Tromey <tom@tromey.com>, gdb-patches@sourceware.org
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From: Tsukasa OI <research_trasio@irq.a4lg.com>
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On 2022/10/15 3:39, Tom Tromey wrote:
>>>>>> Tsukasa OI via Gdb-patches <gdb-patches@sourceware.org> writes:
> 
>> +static int
>> +riscv_print_insn (bfd_vma memaddr, disassemble_info *info)
>> +{
>> +  static disassembler_ftype disassemble_fn = NULL;
>> +  static bfd *abfd = NULL;
> 
> This seems mildly dangerous, in that a BFD could be destroyed, then a
> new one created with the same address.
> 
> It's better to cache things using the registry system.
> See gdb/registry.h.  You can look for "registry<bfd>" for examples.
> 
> Tom
> 

Thanks for letting me know.

Because my opcodes-side optimization on RISC-V will hide most of the
performance improvements made by that proposed patch, I will need to
redo the benchmark after I write a patch to use registry system.  If
registry cost is too high, I will have to scrap this idea instead of
using the registry system.

Thanks,
Tsukasa