what are the steps required for a pipeline process of process the the instructions ? draw a pipeline for (A+B*D)
Answers
Answer:
Explanation:
A pipeline diagram shows the execution of a series of instructions.
— The instruction sequence is shown vertically, from top to bottom.
— Clock cycles are shown horizontally, from left to right.
— Each instruction is divided into its component stages. (We show five
stages for every instruction, which will make the control unit easier.)
This clearly indicates the overlapping of instructions. For example, there
are three instructions active in the third cycle above.
— The “lw” instruction is in its Execute stage.
— Simultaneously, the “sub” is in its Instruction Decode stage.
— Also, the “and” instruction is just being fetched.
add $sp, $sp, -4 IF ID EX MEM WB
or $s0, $s1, $s2 IF ID EX MEM WB
and $t1, $t2, $t3 IF ID EX MEM WB
sub $v0, $a0, $a1 IF ID EX MEM WB
lw $t0, 4($sp) IF ID EX MEM WB
1 2 3 4 5 6 7 8 9
Clock cycle
2
Pipeline terminology
The pipeline depth is the number of stages—in this case, five.
In the first four cycles here, the pipeline is filling, since there are unused
functional units.
In cycle 5, the pipeline is full. Five instructions are being executed
simultaneously, so all hardware units are in use.
In cycles 6-9, the pipeline is emptying.
filling full emptying
add $sp, $sp, -4 IF ID EX MEM WB
or $s0, $s1, $s2 IF ID EX MEM WB
and $t1, $t2, $t3 IF ID EX MEM WB
sub $v0, $a0, $a1 IF ID EX MEM WB
lw $t0, 4($sp) IF ID EX MEM WB
The pipeline depth is the number of stages—in this case, five.
In the first four cycles here, the pipeline is filling, since there are unused
functional units.
In cycle 5, the pipeline is full. Five instructions are being executed
simultaneously, so all hardware units are in use.
In cycles 6-9, the pipeline is emptying.