Make == for associative arrays test for equality, not identity. _aaEq was added to runtime/internal/aaA.d which forwards to TypeInfo_AssociativeArray.equals in genobj.d. On the codegen side, DtoAAEquals was added to gen/aa.cpp and is called from EqualExp::toElem in gen/toir.cpp. I assume that the frontend will produce an error if == is used on associative arrays of different type. This fixes DMD bug 1429.

extern(C) int printf(char*, ...);
void main()
{
    void* i;
    asm
    {
        mov EAX, FS:4;
        mov i, EAX;
    }
    printf("FS:4 = %p\n", i);
}