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movk

The ARM64 instruction that drops a 16-bit number into one quarter of a register and keeps the other bits.

movk xd, #imm16, lsl #s replaces bits s..s+15 of xd with imm16 and preserves the rest; up to three movk after a movz build any 64-bit constant.

Examples

  • After movz x0, #0x1234, lsl #16, movk x0, #0x5678 fills the low 16 bits: x0 = 0x12345678.

See also

movabs movz
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