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AMD Confidential
User Manual September 12
th
, 2008
Appendix A 225
PAVGUSB mmreg1,mmreg2/m64
Average of unsigned packed 8-bit
values.
Converts packed floating-point
operand or packed 32-bit integer.
Floating-point accumulate.
Packed, floating-point addition.
PFCMPEQ mmreg1,mmreg2/m64
Packed floating-point comparison,
equal to.
PFCMPPGE mmreg1,mmreg2/m64
Packed floating-point comparison,
greater than or equal to.
PFCMPGT mmreg1,mmreg2/m64
Packed floating-point comparison,
greater than.
Packed floating-point maximum.
Packed floating-point minimum.
Packed floating-point
multiplication.
Packed floating-point approximation.
PFRCPIT1 mmreg1,mmreg2/m64
Packed floating-point reciprocal,
first iteration step.
PFRCPIT2 mmreg1,mmreg2/m64
Packed floating-point reciprocal,
second iteration step.
PFRSQIT1 mmreg1,mmreg2/m64
Packed floating-point reciprocal,
square root, first iteration step.
PFRSQRT mmreg1,mmreg2/m64
Packed floating-point reciprocal,
square root approximation.
Packed, floating-point subtraction.
Packed, floating-point reverse
subtraction.
Packed 32-bit integer to floating-
point conversion.
PMULHRW mmreg1,mmreg2/m64
Multiply signed packed 16-bit values
with rounding and store the high 16
bits.
Prefetch processor cache line into
L1 data cache (Dcache).
Table 15-10: 3DNow!™ Instruction Reference
A.6.7 Extension to the 3DNow! Instruction Set
This section describes the five new DSP instructions added to the 3DNow! Instruction
set.
Packed floating-point to integer
word conversion with sign extend.
Packed floating-point negative
accumulate.
PFPNACC mmreg1,mmreg2/m64
Packed floating-point mixed
positive-negative accumulate.
Packed 16-bit integer to floating-
point conversion.
Table 15-11: Extension to 3DNow! Instruction Reference
A.6.8 Prescott New Instructions
Prescott New Instruction technology for the x64 architecture is a set of 13 new
instructions that accelerate performance of Streaming SIMD Extension technology,
Streaming SIMD Extension 2 technology, and x87-FP math capabilities. The new
technology is compatible with existing software and should run correctly, without
modification. The thirteen new instructions are summarized in the following section. For
detailed information on each instruction refer to a complete Instruction Set Reference.