38 lines
1.2 KiB
C
38 lines
1.2 KiB
C
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#ifndef __X8664_UNALIGNED_H
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#define __X8664_UNALIGNED_H
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/*
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* The x86-64 can do unaligned accesses itself.
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*
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* The strange macros are there to make sure these can't
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* be misused in a way that makes them not work on other
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* architectures where unaligned accesses aren't as simple.
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*/
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/**
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* get_unaligned - get value from possibly mis-aligned location
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* @ptr: pointer to value
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*
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* This macro should be used for accessing values larger in size than
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* single bytes at locations that are expected to be improperly aligned,
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* e.g. retrieving a u16 value from a location not u16-aligned.
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*
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* Note that unaligned accesses can be very expensive on some architectures.
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*/
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#define get_unaligned(ptr) (*(ptr))
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/**
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* put_unaligned - put value to a possibly mis-aligned location
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* @val: value to place
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* @ptr: pointer to location
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*
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* This macro should be used for placing values larger in size than
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* single bytes at locations that are expected to be improperly aligned,
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* e.g. writing a u16 value to a location not u16-aligned.
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*
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* Note that unaligned accesses can be very expensive on some architectures.
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*/
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#define put_unaligned(val, ptr) ((void)( *(ptr) = (val) ))
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#endif
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