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References: <20240202220459.527138-1-namhyung@kernel.org> <20240202220459.527138-8-namhyung@kernel.org>
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From: Ian Rogers <irogers@google.com>
Date: Fri, 2 Feb 2024 18:49:05 -0800
Message-ID: <CAP-5=fUWbe-owCHsjQfOuTyt8kEzM_M_4GqS_rqKwL9VY3tJOQ@mail.gmail.com>
Subject: Re: [PATCH 07/14] perf annotate-data: Add update_insn_state()
To: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>, Jiri Olsa <jolsa@kernel.org>, 
	Adrian Hunter <adrian.hunter@intel.com>, Peter Zijlstra <peterz@infradead.org>, 
	Ingo Molnar <mingo@kernel.org>, LKML <linux-kernel@vger.kernel.org>, 
	linux-perf-users@vger.kernel.org, 
	Linus Torvalds <torvalds@linux-foundation.org>, Stephane Eranian <eranian@google.com>, 
	Masami Hiramatsu <mhiramat@kernel.org>, linux-toolchains@vger.kernel.org, 
	linux-trace-devel@vger.kernel.org
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On Fri, Feb 2, 2024 at 2:05=E2=80=AFPM Namhyung Kim <namhyung@kernel.org> w=
rote:
>
> The update_insn_state() function is to update the type state table after
> processing each instruction.  For now, it handles MOV (on x86) insn
> to transfer type info from the source location to the target.
>
> The location can be a register or a stack slot.  Check carefully when
> memory reference happens and fetch the type correctly.  It basically
> ignores write to a memory since it doesn't change the type info.  One
> exception is writes to (new) stack slots for register spilling.

Just an aside, it seems a shame objdump can't do this tracking for us.
objdump already augments its output with symbol and relocation data.

Thanks,
Ian