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Question 3 The following code adds a scalar to a vector: For (i=999; i>=0; i=i-1) X[i] = x[i]+ s ; which translates in RISC-V code as: Loop: fld f0,0(x1) fadd.d f4,f0,f2 // f2 has the scalar value s fsd f4,0(x1) addi x1,x1,-8 bne x1,x2, loop // regs[x2]+8 is the add of the last element has a) one way to exploit ILP is loop unrolling, do unroll the above loop to 4 copies of the body

          Question 3
The following code adds a scalar to a vector:
For (i=999; i>=0; i=i-1)
X[i] = x[i]+ s ;
which translates in RISC-V code as:
Loop: fld f0,0(x1)
fadd.d f4,f0,f2
// f2 has the scalar value s
fsd f4,0(x1)
addi x1,x1,-8
bne x1,x2, loop
// regs[x2]+8 is the add of the last element has
a) one way to exploit ILP is loop unrolling, do unroll the above loop to 4 copies
of the body

Question 3
The following code adds a scalar to a vector:
For (i=999; i>=0; i=i-1)
X[i] = x[i]+ s ;
which translates in RISC-V code as:
Loop: fld f0,0(x1)
fadd.d f4,f0,f2
// f2 has the scalar value s
fsd f4,0(x1)
addi x1,x1,-8
bne x1,x2, loop
// regs[x2]+8 is the add of the last element has
a) one way to exploit ILP is loop unrolling, do unroll the above loop to 4 copies
of the body

Added by Christy W.

Computer Science and Information Technology

Trishna Knowledge Systems 2018 Edition

Instant Answer

Solved by Expert Adi S

02/14/2023

Step 1

The loop starts from the last element of `X` and goes up to the first element. Show more…

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Question 3 The following code adds a scalar to a vector: For (i=999; i>=0; i=i-1) X[i] = x[i] + s; which translates in RISC-V code as: Loop: fld f0, 0(x1) fadd.d f4, f0, f2 // f2 has the scalar value s fsd f4, 0(x1) addi x1, x1, -8 bne x1, x2, loop // regs[x2]+8 is the add of the last element a) One way to exploit ILP is loop unrolling, do unroll the above loop to 4 copies of the body.