Computer Organization and Design RISC-V Edition

Figure 2.24 A C procedure that performs a sort on the array v.

Register Allocation for sort

The two parameters of the procedure sort, v and n, are in the parameter registers x10 and x11, and we assign register x19 to i and register x20 to j.

Code for the Body of the Procedure sort

The procedure body consists of two nested for loops and a call to swap that includes parameters. Let’s unwrap the code from the outside to the middle.

The first translation step is the first for loop:

for (i = 0; i < n; i += 1) {

Recall that the C for statement has three parts: initialization, loop test, and iteration increment. It takes just one instruction to ...