Pipelining is a technique used in microprocessors where the execution of an instruction is broken down into stages that can be executed concurrently for different instructions. This allows a new instruction to begin executing before the previous one has finished. The document provides an example of a four-stage integer arithmetic pipeline and calculates the speedup from pipelining over a non-pipelined approach for 100 tasks. It is explained that pipelining can reduce the execution time from 8,000 ns to 2,060 ns, providing a speedup of 3.88x.

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2. A technique used in advanced microprocessors
where it begins executing a second instruction
before the first has been completed.
Decomposing the sequential process into suboperation.
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4.  The pipeline is divided into segments and each
segment can execute it operation concurrently
with the other segments.
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7. R1
Ai , R2
Bi
Input Ai and Bi
R3
R1 * R2, R4
Ci
Multiply and input Ci
R5
R3 + R4
Add Ci to product
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9. Let, 100 task to be completed,
K be no. of pipeline stage =4
Tp be one clock cycle time = 20
Tn= time required by single task =Tp * K
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10. Case: Non-pipelined machine
T=n*Tn
=100*80
=8000 ns
Case: Pipelined machine
T=(K+n-1) * Tp
=103*20
=2060 ns
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11. Speed Up ratio:
n*Tn
(K+n-1) * Tp
8000
2060
Ans: 3.88
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12. 1)
2)
3)
4)
5)
6)
Hardware or software implementation – pipelining can be
implemented in either software or hardware.
Large or Small Scale – Stations in a pipeline can range from simplistic to
powerful, and a pipeline can range in length from short to long.
Synchronous or asynchronous flow – A synchronous pipeline operates
like an assembly line: at a given time, each station is processing some
amount of information. A asynchronous pipeline, allow a station to
forward information at any time.
Buffered or unbuffered flow – One stage of pipeline sends data directly
to another one or a buffer is place between each pairs of stages.
Finite Chunks or Continuous Bit Streams – The digital information that
passes though a pipeline can consist of a sequence or small data items
or an arbitrarily long bit stream.
Automatic Data Feed Or Manual Data Feed – Some implementations of
pipelines use a separate mechanism to move information, and other
implementations require each stage to participate in moving
information.
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13. Usually found in very high speed computers
To implement floating-point operations,
multiplications of fixed point numbers
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14. Steps Of Arithmetic Pipelining





Compare the exponents
Align the mantissa 0.08200
Choose mantissa
Now y=0.08200*103
Add Mantissa= 0.9504 + 0.08200
=1.0324*103
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16. 
Fetch the instruction from memory.

Decode the instruction.

Calculate the effective address.

Fetch the operands from memory.

Execute the instruction.

Store the result in the proper place.
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18. 
FI is the segment that fetches an instruction.

DA is the segment that decodes the instruction
and calculate the effective address.

FO is the segment that fetches the operand.

EX is the segment that executes the instruction.
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