Consider the following code sequence having five instructions $${I_1}$$ to $${I_5}$$. Each of these instructions has the following format.

$$\,\,\,\,\,\,\,\,\,\,\,\,\,\,OP\,\,Ri,\,\,Rj,\,\,Rk$$

where operation $$OP$$ is performed on contents of registers $$Rj$$ and $$Rk$$ and the result is stored in register $$Ri.$$

$$\eqalign{ & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{I_1}:ADD\,\,\,R1,\,R2,\,R3 \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{I_2}:MUL\,\,R7,\,R1,\,R3 \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{I_3}:SUB\,\,\,\,R4,\,R1,\,R5 \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{I_4}:ADD\,\,\,R3,\,R2,\,R4 \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{I_5}:MUL\,\,\,R7,\,R8,\,R9 \cr} $$

Consider the following three statements.

$$\,\,\,\,\,\,S1:\,\,$$ There is an anti-dependence between instructions $${L_2}$$ and $${L_5}$$
$$\,\,\,\,\,\,S2:\,\,$$ There is an anti-dependence between instructions $${L_2}$$ and $${L_4}$$
$$\,\,\,\,\,\,S3:\,\,$$ Within an instruction pipeline an anti-dependence always creates one or more stalls

Which one of above statements is/are correct?

Consider a processor with byte-addressable memory. Assume that all registers, including Program Counter $$(PC)$$ and Program Status Word $$(PSW),$$ are of size $$2$$ bytes. A stack in the main memory is implemented from memory location $${\left( {0100} \right)_{16}}$$ and it grows upward. The stack pointer $$(SP)$$ points to the top element of the stack. The current value of $$SP$$ is $${\left( {016E} \right)_{16}}$$. The CALL instruction is of two words, the first word is the op-code and the second word is the starting address of the subroutine (one word $$= 2$$ bytes). The CALL instruction is implemented as follows:

$$ \bullet \,\,\,\,\,\,\,\,$$ Store the current value of $$PC$$ in the stack
$$ \bullet \,\,\,\,\,\,\,\,$$ Store the value of $$PSW$$ register in the stack
$$ \bullet \,\,\,\,\,\,\,\,$$ Load the starting address of the subroutine in $$PC$$

The content of $$PC$$ just before the fetch of a CALL instruction is $$\left( {5FA0} \right){\,_{16}}.$$ After execution of the CALL instruction, the value of the stack pointer is

A machine has a $$32$$-bit architecture, with $$1$$-word long instructions. It has $$64$$ registers, each of which is $$32$$ bits long. It needs to support $$45$$ instructions, which have an immediate operand in addition to two register operands. Assuming that the immediate operand is an unsigned integer, the maximum value of the immediate operand is ____________.

Consider two processors ܲ$${P_1}$$ and $${P_2}$$ executing the same instruction set. Assume that under identical conditions, for the same input, a program running on $${P_2}$$ takes $$25$$% less time but incurs $$20$$% more $$CPI$$ (clock cycles per instruction) as compared to the program running on ܲ$${P_1}$$ If the clock frequency of ܲ$${P_1}$$ is $$1GHz,$$ then the clock frequency of $${P_2}$$ (in $$GHz$$) is _____________.