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namespace;
include rt;
// bit tricks and float32 conversion as micro-ops
fn show(v) { rt.put_n(v); rt.put_c(' '); }
fn once() {
show(rt.clz(1)); show(rt.clz(0)); show(rt.ctz(8)); show(rt.ctz(0));
show(rt.popcnt(255)); show(rt.popcnt(-1)); show(rt.popcnt(0));
show(rt.bswap(1) == 72057594037927936);
show(rt.rotl(1, 65)); show(rt.rotr(1, 1) < 0); show(rt.rotl(rt.rotr(12345, 7), 7));
show(rt.mulhi(-1, 5)); show(rt.umulhi(-1, 5));
show(rt.f2s(0x3ff8000000000000)); show(rt.s2f(0x3fc00000) == 0x3ff8000000000000);
show(rt.f2s(0x3ff0000000000000)); show(rt.f2s(0x3810000000000000));
rt.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 += rt.popcnt(i) + rt.ctz(i + 1) + rt.clz(i + 1);
a ^= rt.rotl(a, 3) + rt.bswap(i) + rt.f2s(rt.s2f(i));
}
return a;
}
int main() {
once();
rt.put_n(sums(1000)); rt.put_c(10);
return 0;
}
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