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From: John R.
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> ... however 66 66 90 is a pretty strange sequence. 66 is the > operand size override and 90 is nop, so you have a 3-byte useless > instruction. It was compiled on/for x86_64, where 66 66 90 is a NOP that stalls the look-ahead instruction decoder. This is used as alignment filler after an unconditional JMP, in order to save internal CPU resources and power. It happens to run on most 32-bit x86, too. -- |