Bit Spreading Interleave Bits with Zeros

Code

#include <stdio.h>
#include <stdint.h>

uint16_t spread_bits(uint8_t val) {
    uint16_t tmp = 0;
    uint16_t test;
    test = (val & 128); tmp |= (test << 7); val <<= 1;
    test = (val & 128); tmp |= (test << 5); val <<= 1;
    test = (val & 128); tmp |= (test << 3); val <<= 1;
    test = (val & 128); tmp |= (test << 1); val <<= 1;
    test = (val & 128); tmp |= (test >> 1); val <<= 1;
    test = (val & 128); tmp |= (test >> 3); val <<= 1;
    test = (val & 128); tmp |= (test >> 5); val <<= 1;
    test = (val & 128); tmp |= (test >> 7); val <<= 1;
    return tmp;
}

int main() {
    uint8_t val;
    scanf("%hhu", &val);

    uint16_t result = spread_bits(val);
    printf("%u", result);
    return 0;
}

Solving Approach