MMX instruction to shift a register's contents right arithmetically,
double word-wise.
The source is either an
immediate 8 bit value, a
64 bit value in memory, or a
MMX register. The destination is a MMX register. Each
dword of the destination is shifted to the right by the number of bits specified in the source.
Unlike logical shifts (
PSRLD), 0's are NOT shifted in - instead, the leftmost (sign) bit of each double word is used to fill the space.
Compare:
PSRAW,
PSRLD,
PSLLD.