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Date: Mon, 24 Mar 2014 09:11:12 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Neil Horman <nhorman@tuxdriver.com>
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Cc: dev@dpdk.org, "H. Peter Anvin" <hpa@linux.intel.com>
Subject: Re: [dpdk-dev] [RFC UNTESTED PATCH] eal_common_cpuflags: Fix %rbx
 corruption, and simplify the code
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On 03/24/2014 09:06 AM, Neil Horman wrote:
>>
>> If C99-style initializers are permitted in this codebase, I would
>> strongly recommend using them, and then drop the enum field in struct
>> feature_entry and use a macro such as:
>>
> Actually, its a bit simpler than that, the enum parameter is actually completely
> unused, and so can be removed entirely.  The FEAT_DEF macro does what you
> suggest below already, but only for the feature and name fields.
> 
> I'll remove the enum and its definition, and augment the macro to cover the rest
> of the fields.
> 
> Neil
> 
>> #define FEAT(name,leaf,subleaf,reg,bit) \
>> 	[RTE_CPUFLAG_##f] = { leaf, subleaf, reg, bit, #f },
>>
>> (I'd move the string to the end, but that is just a microoptimization.
>> I'm kind of OCD that way.)
>>

The nice thing with the C99 initializer is that even if the order is
mismatched between the .c file and the .h file which defines the enum,
things still work correctly.

	-hpa