Make "`aa[key]`" use the same runtime call as "`key in aa`". The runtime calls these were using were different, but with equivalent definitions. With `ldc -O3`, the following functions now all compile to the exact same code: {{{ int[int] y; void foo(int x) { if (x in y) { auto z = x in y; sink(*z); } } void bar(int x) { if (x in y) { sink(y[x]); } } void baz(int x) { if (auto p = x in y) { sink(*p); } } }}}

module mini.atomic1;

pragma(intrinsic, "llvm.atomic.swap.i#.p0i#")
    T atomic_swap(T)(T* ptr, T val);

void main()
{
    int i = 42;
    int j = atomic_swap(&i, 43);
    assert(j == 42);
    assert(i == 43);
}