What are the five steps in MIPS instruction execution?

1 Answer

Answer :

1. Fetch instruction from memory.
2. Read registers while decoding the instruction. The regular format of MIPS instructions allows
reading and decoding to occur simultaneously.
3. Execute the operation or calculate an address.
4. Access an operand in data memory.
5. Write the result into a register.

Related questions

Description : What are the floating point instructions in MIPS?

Last Answer : MIPS supports the IEEE 754 single precision and double precision formats with these instructions: Floating-point addition Floating-point subtraction Floating-point multiplication Floating-point division Floating-point comparison Floating-point branch

Description : What are the steps required for a pipelined processor to process the instruction?

Last Answer : • F Fetch: read the instruction from the memory • D Decode: decode the instruction and fetch the source operand(s). • E Execute: perform the operation specified by the instruction. • W Write: store the result in the destination location

Description : Explain out of order execution.

Last Answer : It is a situation in pipelined execution when an instruction blocked from executing does not cause the following instructions to wait.

Description : How CPU execution time for a program in calculated?

Last Answer : CPU execution time for a program = CPU clock cycle for a program X Clock cycle time

Description : What is Instruction Level Parallelism?

Last Answer : Pipelining is used to overlap the execution of instructions and improve performance. This potential overlap among instructions is called instruction level parallelism (ILP).

Description : Assume a two address format specified as source, destination. Examine the following sequence of instruction and explain the addressing modes used and the operation done in every instruction?

Last Answer : 1. Move (R5) +, R0 2. Add (R5) +, R0. 3. Move (R0), (R5) 4. Move 16(R5), R3 5. Add #40, R5

Description : How to represent instruction in a computer system?

Last Answer : An instruction is an order given to a computer processor by a computer program. At the lowest level, each instruction is a sequence of 0s and 1s that describes a physical operation the computer is to ... data to be used in carrying out the instruction, or the location in computer memory of data.

Description : What are the steps in the floating-point addition?

Last Answer : The steps in the floating-point addition are: 1. Align the decimal point of the number that has the smaller exponent. 2. Addition of the significands. 3. Normalize the sum. 4. Round the result

Description : Which is most commonly measured in terms of MIPS previously million instruction per second: a. Microprocessor b. Performance of a microprocessor c. Assembly line d. None of thes

Last Answer : b. Performance of a microprocessor

Description : Define latency time?

Last Answer : This is the amount of time that elapses after the head is positioned over the correct track until the starting position of the addressed sector passes under the read/write head.

Description : What are the components of memory management unit?

Last Answer : 1. A facility for dynamic storage relocation that maps logical memory references into physical memory addresses. 2. A provision for sharing common programs stored in memory by ... information against unauthorized access between users and preventing users from changing operating system functions.

Description : Define Direct Memory Access?

Last Answer : A mechanism that provides a device controller with the ability to transfer data directly to or from the memory without involving the processor.

Description : What is Polling?

Last Answer : The process of periodically checking the status of an I/O device to determine the need to service the device.

Description : Define Translation-Lookaside Buffer (TLB)?

Last Answer : Most commercial virtual memory systems incorporate a mechanism that can avoid the bulk of the main memory access called for by the virtual to physical addresses translation buffer. This may be done with a cache memory called a translation buffer, which retains the results of the recent translation.

Description : Define Segmentation?

Last Answer : A variable-size address mapping scheme in which an address consists of two parts: a segment number,which is mapped to a physical address, and a segment offset.

Description : What is Virtual Memory?

Last Answer : A technique that uses main memory as a cache for secondary storage, usually implemented with magnetic disks. Virtual memory used to allow efficient and safe sharing of memory among multiple programs.

Description : Define Least Recently Used?

Last Answer : A replacement scheme in which the block replaced is the one that has been unused for the longest time.LRU replacement is implemented by keeping track of when each element in a set was used relative to the other elements in the set.

Description : Define Cache Miss?

Last Answer : A request for data from the cache that cannot be filled because the data is not present in the cache. The control unit must detect a miss and process the miss by fetching the requested data from memory.

Description : What is Direct mapped cache?

Last Answer : A cache structure in which each memory location is mapped to exactly one location (address) in the cache. This done by (Block Address) modulo (Number of blocks in the cache).

Description : What is meant by Bus arbitration?

Last Answer : It is a way of sharing the computer’s data transferring channels in an optimal way so that faster devices won’t have to wait to be able to transfer and the slower devices will have a chance to transfer as well

Description : What is Interrupt?

Last Answer : An interrupt is an unscheduled event that disrupts program execution, used to detect overflow

Description : Define Hit ratio?

Last Answer : Hit ratio or Hit rate is the fraction of memory accesses found in the upper level memory hierarchy. Hit ratio is often used as a measure of the performance of the memory hierarchy.

Description : What are the various memory technologies?

Last Answer : Flash memory, RAM – Random Access Memory, ROM – Read Only Memory etc

Description : State the advantages of virtual memory?

Last Answer : Virtual memory is feature of OS that allows a computer to compensate for shortage of physical memory by temporarily transferring pages of data from Random Access Memory to Disk

Description : Define Memory hierarchy?

Last Answer : 1. Processor memory 2. Main memory 3. Secondary memory

Description : Point out how DMA can improve I/O speed.

Last Answer : DMA is implemented with a specialized controller that transfers data between an I/O device and memory independent of the processor The DMA controller becomes the master and directs the reads and writes between itself and memory. During data transfer is not routed through the processors

Description : What is the need to implement memory as a hierarchy?

Last Answer : The aim of the memory hierarchy is to match the processors speed with the rate of information transfer at a lowest level and at a minimum possible cost

Description : What is the purpose of dirty/modified bit in Cache memory?

Last Answer : To tackle whether a page has been written since it was read into the memory, o dirty but is added to the page table.

Description : Differentiate Programmed I/O and Interrupt I/O?

Last Answer : Interrupt I/O is more efficient than Programmed I/O because it eliminates needless waiting However Interrupt I/O consumes a lot of processors time

Description : Define a process.

Last Answer : A process includes one or more threads, the address space and the operating system state. During a process switch operating system is invoked.

Description : Define a Thread.

Last Answer : A thread includes the program counter, the register state and stack. It is a lightweight process. The commonly share a single address space.

Description : Explain dynamic pipeline scheduling.

Last Answer : Here with the hardware support we perform the reordering of the order of instruction execution so as to avoid stalls.

Description : Define a reservation station?

Last Answer : Define a reservation station?

Description : What are Superscalar processors?

Last Answer : It is an advanced pipelining technique that enables the processor to execute more than one instruction per clock cycle.

Description : What is multiple issue? Write any two approaches.

Last Answer : Multiple issues is a scheme whereby multiple instructions are launched in one clock cycle. It is a method for increasing the potential amount of instruction-level parallelism. It is done by replicating the ... 1. Static multiple issue (at compile time) 2. Dynamic multiple issue (at run time)

Description : What is multicore'?

Last Answer : At its simplest, multi-core is a design in which a single physical processor contains the core logic of more than one processor. The multi-core design takes several such processor "cores" ... to enable a system to run more tasks simultaneously and thereby achieve greater overall system performance.

Description : Define a super scalar processor?

Last Answer : It is a CPU that implements a form of parallelism called Instruction level parallelism with a single processor.

Description : What is fine grained multithreading?

Last Answer : This multithreading switch between threads on each instruction, resulting in interleaved execution of multiple treads

Description : Compare UMA and NUMA multiprocessors?

Last Answer : UMA: Multiprocessors take about same time to access main memory no matter which processors request it and no matter which word is requested. NUMA: Some memory accesses are much faster than others, depending on which processors ask for the word.

Description : 5. Differentiate between Strong Scaling and Weak Scaling?

Last Answer : Strong scaling: Measuring speedup by increasing the size of the problem Weak scaling: The program size grows proportionally to the increase in the number of processors

Description : What is Flynn’s classification?

Last Answer : SISD – Single Instruction Single DataStream SIMD – Single Instruction Multiple DataStream MISD – Multiple Instruction Multiple DataStream MIMD – Multiple Instruction Multiple DataStream

Description : What is meant by hardware multithreading?

Last Answer : Hardware multithreading allows multiple threads to share the functional units of a single processor in an overlapping fashion to try to utilize the hardware resources efficiently. To permit this sharing ... duplicate the independent state of each thread. It Increases the utilization of a processor.

Description : What is Multithreading?

Last Answer : Multithreading allows multiple threads to share the functional units of a single processor in an overlapping fashion. To permit this sharing, the processor must duplicate the independent state of each thread.

Description : Explain data path and its control line in detail?

Last Answer : -Implementation of instructions (Arithmetic & logic, Memory reference, Branch Instruction) -Program Counter- It holds the address of the current instruction -Instruction Memory- It store the instructions ... inputs -Register File: The processors 32 General Purpose Registers are stored here. -ALU-

Description : What are the 5 pipeline stages?

Last Answer : The 5 stages of instruction execution in a pipelined processor are: 1. IF: Instruction fetch 2. ID: Instruction decode and register file read 3. EX: Execution or address calculation 4. MEM: Data memory access 5. WB: Write back.

Description : How are jumps implemented?

Last Answer : We can implement a jump by storing into the PC the concatenation of ■ the upper 4 bits of the current PC + 4 (these are bits 31:28 of the sequentially following instruction address) ■ the 26-bit immediate field of the jump instruction ■ the bits 00two

Description : What is pipeline stall?

Last Answer : Pipeline stall, also called bubble, is a stall initiated in order to resolve a hazard. They can be seen elsewhere in the pipeline.

Description : Define Forwarding?

Last Answer : Also called bypassing. A method of resolving a data hazard by retrieving the missing data element from internal buffers rather than waiting for it to arrive from programmer visible registers or memory.

Description : What is meant by sign extend?

Last Answer : To increase the size of a data item by replicating the high-order sign bit of the original data item in the high order bits of the larger, destination data item..