platform-rdcycle.h

// Copyright Microsoft and CHERIoT Contributors.
// SPDX-License-Identifier: MIT
 
#pragma once
 
#include <cdefs.h>
 
/// Read the least significant word of the cycle counter.
__always_inline static int rdcycle()
{
    int cycles;
    // rdcycle is just "csrr %0, cycle" (CSR 0xC00, not mcycle (0xB00)).
    __asm__ volatile("rdcycle %0" : "=r"(cycles));
    return cycles;
}