> +{
> + asm("lea 40f(, %[slen], 4), %%r11\n\t"
> + "clc\n\t"
> + "jmpq *%%r11\n\t"
> + "adcq 7*8(%[src]),%[res]\n\t"
> + "adcq 6*8(%[src]),%[res]\n\t"
> + "adcq 5*8(%[src]),%[res]\n\t"
> + "adcq 4*8(%[src]),%[res]\n\t"
> + "adcq 3*8(%[src]),%[res]\n\t"
> + "adcq 2*8(%[src]),%[res]\n\t"
> + "adcq 1*8(%[src]),%[res]\n\t"
> + "adcq 0*8(%[src]),%[res]\n\t"
> + "nop\n\t"
> + "40: adcq $0,%[res]"
> + : [res] "=r" (sum)
> + : [src] "r" (buff),
> + [slen] "r" (-((unsigned long)(len >> 3))), "[res]" (sum)
> + : "r11");
> +
With this patch I cannot mix/match different length checksums without
things failing. In perf the jmpq in the loop above seems to be set to
a fixed value so perhaps it is something in how the compiler is
interpreting the inline assembler.
- Alex
