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// bit tricks and float32 conversion as micro-ops
fn show(v) { put_n(v); put_c(' '); }
fn once() {
show(clz(1)); show(clz(0)); show(ctz(8)); show(ctz(0));
show(popcnt(255)); show(popcnt(-1)); show(popcnt(0));
show(bswap(1) == 72057594037927936);
show(rotl(1, 65)); show(rotr(1, 1) < 0); show(rotl(rotr(12345, 7), 7));
show(mulhi(-1, 5)); show(umulhi(-1, 5));
show(f2s(0x3ff8000000000000)); show(s2f(0x3fc00000) == 0x3ff8000000000000);
show(f2s(0x3ff0000000000000)); show(f2s(0x3810000000000000));
put_c(10);
}
// the same in a loop, so o3 lifts and fuses them
o3 int sums(int n) {
int a = 0;
for (int i = 0; i < n; i++) {
a += popcnt(i) + ctz(i + 1) + clz(i + 1);
a ^= rotl(a, 3) + bswap(i) + f2s(s2f(i));
}
return a;
}
int main() {
once();
put_n(sums(1000)); put_c(10);
return 0;
}
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