PMOVMSKB
Usage: PMOVMSKB dest,src Modifies flags: None
Returns in 'dest' an 8-bit or 16-bit mask formed of the most significant bits of each byte of 'src' operand.
Move Byte Mask To Integer
PMOVMSKB reg32,mm ; 0F D7 /r [KATMAI,MMX]
PMOVMSKB reg32,xmm ; 66 0F D7 /r [WILLAMETTE,SSE2]
PMOVMSKB creates a mask made up of the most significant bit of each byte of the 'src' (2nd operand) and stores the result in the low byte or word of the 'dest' ( 1st operand).
The 'src' operand is an MMX technology register or an XMM register; the 'dest' operand is a general-purpose register.
When operating on 64-bit operands, the byte mask is 8 bits; when operating on 128-bit operands, the byte mask is 16-bits.
EXAMPLE:
pmovmskb ebx xmm1