MASKMOVQ
Usage: MASKMOVQ src,mask Modifies flags: None
Stores selected bytes from the 'src' into a 64-bit memory location. The 'mask' selects which bytes from the 'src' operand are written to memory.
Byte Mask Write
MASKMOVQ mm1,mm2 ; 0F F7 /r [KATMAI,MMX]
MASKMOVQ stores data from mm1 to the location specified by ES:EDI. The size of the store depends on the address-size attribute. The most significant bit in each byte of the mask register mm2 is used to selectively write the data (0 = no write, 1 = write) on a per-byte basis.
The 'src' and 'mask' operands are MMX technology registers. The location of the first byte of the memory location is specified by DI/EDI and DS registers. (The size of the store address depends on the address-size attribute.)
EXAMPLE:
maskmovq mm1 mm2