Opcode PSUBSW


CPU: all which supported IA MMX:
Pentium (P55C only), Pentium (tm) Pro (P6) future models
Type of Instruction: User

Instruction: PSUBSW dest,src

Description:

dest[15..0] <- SaturateToSignedWord(dest[15..0] - src[15..0])
dest[31..16] <- SaturateToSignedWord(dest[31..16] - src[31..16])
dest[47..32] <- SaturateToSignedWord(dest[47..32] - src[47..32])
dest[63..48] <- SaturateToSignedWord(dest[63..48] - src[63..48])

Note: This instruction subtract signed packed word in MMXregister/memory
from signed packed word in MMX register and saturate.
If the result is larger or smaller than the range of a signed word,
the value is saturated; in the case of an overflow - to 7FFFH, and the
case of an underflow - to 8000H

Flags affected: None

Exceptions:

RM PM VM SMM Description
#GP(0) If Illegal memory operand's EA in CS,DS,ES,FS,GS
#SS(0) If illegal memory operand's EA in SS
#PF(fcode) If page fault
#AC #AC If unaligned memory reference then alignment
check enabled and in ring 3.
#UD #UD #UD #UD If CR0.EM = 1
#NM #NM #NM #NM If CR0.TS = 1
#MF #MF #MF #MF If pending FPU Exception
#13 #13 If any part of the the operand lies outside of
the EA space from 0 to FFFFH
++++++++++++++++++++++++++++++++++++++
COP & Times:

PSUBSW mm,mm/m64 0FH E9H PostByte

P55C: n/a
future P6: n/a


Copyright by InternetNightmare 2005-2006