What are the three types of hazards in pipelines?

There are mainly three types of data hazards:

• RAW (Read after Write) [Flow/True data dependency]
• WAR (Write after Read) [Anti-Data dependency]
• WAW (Write after Write) [Output data dependency]

What is the purpose of forwarding in a pipelined processor?

Operand forwarding (or data forwarding) is an optimization in pipelined CPUs to limit performance deficits which occur due to pipeline stalls. A data hazard can lead to a pipeline stall when the current operation has to wait for the results of an earlier operation which has not yet finished.

What is the purpose of the forwarding unit?

The forwarding unit sets the control signals for the two multiplexors shown to the left of the ALU (Fig 1), called ForwardA for the top multiplexor (corresponding to the left operand to the ALU) and ForwardB for the lower multiplexor (corresponding to the right operand for the ALU).

Does forwarding eliminate all data hazards?

For the next instruction, AND, data is forwarded from the MEM/WB buffer. There are thus instances where stalls may occur even with forwarding. However, forwarding is helpful in minimizing hazards and sometimes in totally eliminating them.

What are pipeline hazards explain the different types of pipeline hazards with suitable examples?

There are three types of hazards: Structural hazards: Hardware cannot support certain combinations of instructions (two instructions in the pipeline require the same resource). Data hazards: Instruction depends on result of prior instruction still in the pipeline.

What is pipeline hazards in computer architecture?

Pipeline hazards are situations that prevent the next instruction in the instruction stream from executing during its designated clock cycles. Any condition that causes a stall in the pipeline operations can be called a hazard.

What is control hazard?

Control hazards (branch hazards or instruction hazards) Control hazard occurs when the pipeline makes wrong decisions on branch prediction and therefore brings instructions into the pipeline that must subsequently be discarded. The term branch hazard also refers to a control hazard.

What is a load use hazard?

and STALL lw A load-use hazard requires delaying the execution of the using instruction until the result from the loading instruction can be made available to the using instruction. Page 3. Pipeline Stalls 3.

Which of the following is a pipeline hazard?

Pipeline hazards are situations that prevent the next instruction in the instruction stream from executing during its designated clock cycles. Any condition that causes a stall in the pipeline operations can be called a hazard. iii. Structural Hazards.

What are the 4 major types of hazards?

There are four types of hazards that you need to consider:

• Microbiological hazards. Microbiological hazards include bacteria, yeasts, moulds and viruses.
• Chemical hazards.
• Physical hazards.
• Allergens.