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// The following is a RISC-V program to test the functionality of the
// dummy RoCC accelerator.
// Compile with riscv64-unknown-elf-gcc dummy_rocc_test.c
// Run with spike --extension=dummy_rocc pk a.out
#include <assert.h>
#include <stdio.h>
#include <stdint.h>
int main() {
uint64_t x = 123, y = 456, z = 0;
// load x into accumulator 2 (funct=0)
asm volatile ("custom0 x0, %0, 2, 0" : : "r"(x));
// read it back into z (funct=1) to verify it
asm volatile ("custom0 %0, x0, 2, 1" : "=r"(z));
assert(z == x);
// accumulate 456 into it (funct=3)
asm volatile ("custom0 x0, %0, 2, 3" : : "r"(y));
// verify it
asm volatile ("custom0 %0, x0, 2, 1" : "=r"(z));
assert(z == x+y);
// do it all again, but initialize acc2 via memory this time (funct=2)
asm volatile ("custom0 x0, %0, 2, 2" : : "r"(&x));
asm volatile ("custom0 x0, %0, 2, 3" : : "r"(y));
asm volatile ("custom0 %0, x0, 2, 1" : "=r"(z));
assert(z == x+y);
printf("success!\n");
}
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