Q5 C RISC-V

4 Points

In each of the following questions, you'll be given either C or RISC-V code, and asked to examine a translation into RISC-V or C, respectively.

The translation may have a bug or logic error. Your task is to identify the line number containing the error, or enter "none" if no problem exists.

(a) Given this C code:

if (x < 3) { goto label; }

Identify the buggy line in the following RISC-V translation. Select "None", if there is no error.

/* x = s0 */ 1. addi t0 x0 3 2. slt t1 s0 t0 3. beq t1 x0 label

(b) Given this C code:

int x[2] = {1, 2} int y = x[0] + x[1] + 2;

identify the buggy line in the following RISC-V translation or enter "none", if there is none:

/* x = s0, y = s1 */ 1. lw t0 0(s0) 2. lw t1 1(s0) 3. add s1,t0,t1 4. addi s1,s1,2

(c) Given this RISC-V code:

add s0 s0 s2 sub s1 s2 s1 j end

identify the buggy line in the following C translation or enter "none", if there is none. (Hint: register order matters):

/* x = s0, y = s1, z = s2 */ 1. x += z 2. y -= z 3. goto end

(d) Given this RISC-V code:

slli s0 s0 4 xori s0 s0 3 sw s0 8(s1)

identify the buggy line in the following C translation or enter "none", if there is none:

1. int x; // x = s0 2. int y[3]; // y = s1 3. x *= math.pow(2, 4); 4. x ^= 3 5. y[4] = x;