Description
For the following C statement, write the corresponding RISC-V assembly code. Assume that the C variables f, g, and h, have already been placed in registers x28, x29, and x30 respectively. Use a minimal number of RISC-V assembly instructions. f = g + (h − 9);
Translate the following C code to RISC-V. Assume that the variables f, g, h, i, and j are assigned to registers x5, x6, x7, x28, and x29, respectively. Assume that the base address of the arrays A and B are in registers x10 and x11, respectively. Assume that the elements of the arrays A and B are 4-byte words:
B[8] = A[i] + A[j];
- (Translate the following loop into C. Assume that the C-level integer i is held in register x5, x6 holds the C-level integer called result, and x10 holds the base address of the integer MemArray. addi x6, x0, 0 addi x29, x0, 100
LOOP: lw x7, 0(x10) add x5, x5, x7 addi x10, x10, 4 addi x6, x6, 1 blt x6, x29, LOOP
Show how the value 0x12345678 would be arranged in memory of a littleendian and a big-endian machine. Assume the data are stored starting at word address 0.
- Assume the following register contents:
x5 = 0x0000AAAA, x6 = 0x12345678
- For the register values shown above, what is the value of x7 for the following sequence of instructions?
slli x7, x5, 4
- For the register values shown above, what is the value of x7 for the following sequence of instructions?
srli x7, x5, 3 andi x7, x7, 0xFEF
- Assume x5 holds the value 0x01010000. What is the value of x6 after the following instructions?
bge x5, x0, ELSE jal x0, DONE ELSE: ori x6, x0, 2
DONE: ……
- Consider the following RISC-V loop:
LOOP: beq x6, x0, DONE addi x6, x6, -1 addi x5, x5, 2
jal x0, LOOP
DONE: ……
- Assume that the register x6 is initialized to the value 10. What is the final value in register x5 assuming the x5 is initially zero?
- For the loop above, write the equivalent C code. Assume that the registers x5 and x6 are integers acc and i, respectively.
- For the loop written in RISC-V assembly above, assume that the register x6 is initialized to the value N. How many RISC-V instructions are executed?
- For the loop written in RISC-V assembly above, replace the instruction “beq x6, x0, DONE” with the instruction “blt x6, x0, DONE” and write the equivalent C code.
8) Translate the following C code to RISC-V assembly code. Use a minimum number of instructions. Assume that the values of a, b, i, and j are in registers x5, x6, x7, and x29, respectively. Also, assume that register x10 holds the base address of the array D. for(i=0; i<a; i++) for(j=0; j<b; j++) D[4j] = i + j;
