Which of the following are NOT true in a pipelined processor?
$$1.$$ Bypassing can handle all RAW hazards
$$2.$$ Register renaming can eliminate all register carried WAR hazards
$$3.$$ Control hazard penalties can be eliminated by dynamic branch prediction.

The use of multiple register windows with overlap causes a reduction in the number of memory accesses for
$$1.\,\,\,\,$$ Function locals and parameters
$$2.\,\,\,\,$$ Register saves and restores
$$3.\,\,\,\,$$ Instruction fetches

Consider a pipelined processor with the following four stages
$$\,\,\,\,\,$$$$IF:$$ Instruction Fetch
$$\,\,\,\,\,$$$$ID:$$ Instruction Decode and Operand Fetch
$$\,\,\,\,\,$$$$EX:$$ Execute
$$\,\,\,\,\,$$$$WB:$$ Write Back

The $$IF, ID$$ and $$WB$$ stages take one clock cycle each to complete the operation. The number of clock cycles for the $$EX$$ stage depends on the instruction. The $$ADD$$ and $$SUB$$ instructions need $$1$$ clock cycle and the $$MUL$$ instruction needs $$3$$ clock cycles in the $$EX$$ stage. Operand forwarding is used in the pipelined processor. What is the number of clock cycles taken to complete the following sequence of instructions?

A CPU has five stages pipeline and runs at $$1$$ $$GHz$$ frequency. Instruction fetch happens in the first stage of the pipeline. A conditional branch instruction computes the target address and evaluates the condition in the third stage of the pipeline. The processor stops fetching new instruction following a conditional branch until the branch outcome is known. A program executes $${10^9}$$ instructions out of which $$20$$% are conditional branches. If each instruction takes one cycle to complete on average, then total execution time of the program is