7. A computer has 32-bit instructions and 12-bit addresses. Suppose there are 250 2-address instructions. How many 1-address instructions can be formulated? Explain your answer.
In a computer with 32-bit instructions and 12-bit addresses, we can determine the number of 1-address instructions that can be formulated based on the given information.
For 2-address instructions, each instruction requires two addresses: one for the source operand and one for the destination operand. Since the addresses are 12 bits each, the total number of 2-address instructions that can be formulated is given by:
Number of 2-address instructions = 2(2 * 12) = 224 = 16,777,216
Now, let's determine the number of 1-address instructions. In a 1-address instruction, there is one address used for both the source and destination operands. Since the computer has 32-bit instructions, we can consider the address field to be 32 bits long.
The total number of possible addresses that can be represented by 32 bits is given by:
Number of addresses = 232 = 4,294,967,296
However, we need to account for the fact that the address field in a 1-address instruction can only accommodate 12 bits. So, the number of 1-address instructions that can be formulated is limited by the number of possible 12-bit addresses within the 32-bit address space.
Number of 1-address instructions = 2(1 * 12) = 212 = 4,096
Hence, in a computer with 32-bit instructions and 12-bit addresses, if there are 250 2-address instructions, it is possible to formulate 4,096 1-address instructions.