wmaker/wrlib/bench.h

inline static void
cycle_bench(int start)
{
    static volatile unsigned int start_cycle;

    if (start) {
        asm volatile
            ("pushl %%edx	\n\t"
             "rdtsc         	\n\t"
             "movl %%eax,%0  	\n\t"
             "cld            	\n\t"
             "popl %%edx	\n\t"
             "nop            	\n\t"
             "nop            	\n\t"
             "nop            	\n\t"
             "nop            	\n\t"
             "nop            	\n\t"
             "nop       	\n\t"
             "nop            	\n\t"
             "nop    	        \n\t"
             : "=m" (start_cycle) : : "eax", "edx");
    } else {
        volatile int end;

        asm volatile
            ("pushl %%edx	\n\t"
             "clc            	\n\t"
             "rdtsc          	\n\t"
             "movl %%eax, %0	\n\t"
             "popl %%edx	\n\t"
             : "=m" (end) : : "eax", "edx");

        printf("Cycle count = %u\n", end - start_cycle - 68);
    }
}



#if 0
// seems linux doesnt allow user progs to exec rdpcm..
inline static void
cache_bench(int start)
{
    static int start_cycle;

    if (start) {
        asm volatile
            ("movl $1,%%ecx	\n\t"
             "rdpmc             \n\t"
             "movl %%eax,%0     \n\t"
             : "=m" (start_cycle));
    } else {
        int end;

        asm volatile
            ("movl $1,%%ecx	\n\t"
             "rdpmc             \n\t"
             "movl %%eax,%0"
             : "=m" (end));

        printf("Cache reloads counted = %i\n", end - start_cycle);
    }
}

#endif