Messages in this thread | | | Date | Wed, 3 Jun 2015 09:04:41 +0200 | From | Ingo Molnar <> | Subject | Re: [PATCH 1/2] x86/asm/entry/32: Open-code CLEAR_RREGS. No code changes. |
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* Steven Rostedt <rostedt@goodmis.org> wrote:
> On Tue, 2 Jun 2015 21:04:01 +0200 > Denys Vlasenko <dvlasenk@redhat.com> wrote: > > > This macro is small, has only four callsites, and one of them is slightly > > different using a conditional parameter. > > > > A few saved lines aren't worth the resulting obfuscation. > > I'm curious, why? Did someone recommend this change? I don't see it as > obfuscation at all.
So here are a few easy questions, I'm wondering how many minutes it takes for you to answer them correctly:
- What does the CLEAR_RREGS name stand for?
- What is this macro's purpose?
- In a single case CLEAR_RREGS takes a 'r9' argument:
arch/x86/ia32/ia32entry.S: CLEAR_RREGS arch/x86/ia32/ia32entry.S: CLEAR_RREGS arch/x86/ia32/ia32entry.S: CLEAR_RREGS r9 arch/x86/ia32/ia32entry.S: CLEAR_RREGS arch/x86/ia32/ia32entry.S: CLEAR_RREGS
What is the 'r9' argument's purpose and why is activated in the place where it's activated?
The CLEAR_RREGS macro has zero comments. If it takes more than a quick glance to determine all these three first-order questions from the source code, then it's an obvious code cleanliness fail which needs to be improved.
Thanks,
Ingo
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