AMD Typewriter x86 사용자 설명서

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22007E/0—November 1999
AMD Athlon™ Processor x86 Code Optimization 
Select DirectPath Over VectorPath Instructions
219
Appendix G
DirectPath versus 
VectorPath Instructions
Select DirectPath Over VectorPath Instructions
U s e   D i r e c t P a t h   i n s t r u c t i o n s   r a t h e r   t h a n   Ve c t o r P a t h
instructions.
 DirectPath instructions are optimized for decode
and execute efficiently by minimizing the number of operations
per x86 instruction, which includes ‘register
register op
memory’ as well as ‘register
register op register’ forms of
instructions.
DirectPath Instructions
The following tables contain DirectPath instructions, which
should be used in the AMD Athlon processor wherever possible:
All 3DNow! instructions, including the 3DNow! Extensions, 
are DirectPath and are listed in Table 23, “3DNow!™ 
Instructions,” on page 217 a
nd Table 24, “3DNow!™ Exten-
sions,” on page 218.