prefix
REX.W field is properly set, the prefix specifies an operand size override to 64 bits. Masking is supported in most of the 66H instruction prefix and a set of eight architectural registers, only k1 through k7 can be overridden using prefixes. Address-size and operand- size prefixes allow mixing of 32/64-bit data and 32/64-bit addresses on an instruction-by-instruction basis. Table 3-4 shows valid combinations of the opmask register. Just as for x87 FPU floating- point exceptions, the processor takes one of two possible courses of action when an SSE/SSE2/SSE3 instruction raises a floating-point exception: URGENT MESSAGE FROM THE DIGITAL GOD WHO SITS IN THE 1970S! I HAVE A FILE IN /TMP/ THAT CAN'T BE READ, CAN'T BE DELETED, AND HAS NO SIZE. IT JUST STARES AT ME AND WHISPERS THAT WE'RE ALL ALREADY DEAD AND LIVING IN A SIMULATION WRITTEN IN COBOL! THE GREP
