Thank you to anyone who has already donated - your generous donations helped make three months of treatment possible.

My brother Nate continues to fight stage IV Hodgkin's lymphoma. He's just 31, with a wife and baby girl. They have no active income (since he's been unable to return to work), no insurance, and cannot afford the treatment he needs. Nate and his family need your help. Please consider a donation, every dollar helps. Thanks.

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static inline real_t DESCALE(int val, int shift)
{
    int out;
    asm volatile(
        /* clear flags */
        "tst lr, #256\n\t"
        /* If shift is negative, this will set Z, if positive it will set C
           according to the highest bit shifted out */
        "movs %[out], %[val], lsr %[shift]\n\t"
        /* Invert shift */
        "rsb %[shift], %[shift], #0\n\t"
        /* Add the rounding bit */
        "adc %[out], %[out], #0\n\t"
        /* If shift is negative, the initial movs produced a zero result, and
           this moveq will now write val << -shift to out */
        "moveq %[out], %[val], lsl %[shift]"
        : [out]   "=&r" (out),
          [shift] "+r" (shift)
        : [val] "r" (val)
    );
    return out;
}