MMX instruction to shift a register's contents left.
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. The destination is shifted to the left by the number of bits specified in the source. 0's are shifted in from the
bit bucket to fill the new spaces on the right side.
Compare:
PSLLD,
PSLLW,
PSRLQ.