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Suppose the program counter (PC) is set to 0x2000 0000. Is it possible to use the jump (j) MIPS assembly instruction to set the PC to the address as 0x4000 0000? Is it possible to use the branch-on-equal (beq) MIPS assembly instruction to set the PC?

User Eldshe
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Final answer:

Directly setting the PC to 0x40000000 using the jump (j) or branch-on-equal (beq) MIPS assembly instructions is not possible.

The jump instruction can target only within the same 256MB segment, and the beq instruction is limited to a ± 128KB range from the PC.

Step-by-step explanation:

The program counter, also known as the instruction pointer or simply PC, is a fundamental component of a computer's central processing unit (CPU).

If the program counter (PC) is set to 0x20000000, using the jump (j) MIPS assembly instruction to set the PC to 0x40000000 directly is not possible.

This is because the jump instruction can only specify a target address within the same 256MB segment as the instruction itself due to the encoding of the target address in the lower 28 bits of the instruction.

Hence, the jump can only cover a range of 0x20000000 to 0x2FFFFFFF in this case.

As for the branch-on-equal (beq) MIPS assembly instruction, it is also not capable of directly setting the PC to 0x40000000 as it uses PC-relative addressing.

The beq instruction offsets the PC by a 16-bit immediate value, which is sign-extended and multiplied by 4 to provide a range of ± 128KB from the current PC address.

Therefore, it cannot reach 0x40000000 from 0x20000000 as this exceeds the branching range.

User Ntysdd
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