Far Jumps in Real-Address or Virtual-8086 Mode. When executing a far jump in real-address or virtual-8086 mode, the processor jumps to the code segment and offset specified with the target operand. Here the target operand specifies an absolute far address either directly with a pointer (ptr16:16 or ptr16:32) or indirectly with a memory location (m16:16 or m16:32). With the pointer method, the segment and address of the called procedure is encoded in the instruction, using a 4-byte (16-bit operand size) or 6-byte (32-bit operand size) far address immediate. With the indirect method, the target operand specifies a memory location that contains a 4-byte (16-bit operand size) or 6-byte (32-bit operand size) far address. The far address is loaded directly into the CS and EIP registers. If the operand-size attribute is 16, the upper two bytes of the EIP register are cleared.
JMP 10 (32-bit)l
Unsigned immediate divisors, which are a power of two (from 2 to 256), are optimized to shifts. Divisions by 1 are replaced by TST.L Dn (32-bit) or MVZ.W Dn,Dn (16-bit, ColdFire only). Divisions by -1 are replaced by NEG.L Dn (32-bit) or by a combination of NEG.W Dn and MVZ.W Dn,Dn (16-bit, ColdFire only). This optimization will leave the flags in a different state as can normally be expected after a division instruction. 2ff7e9595c
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