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Arrays at the hardware level can be implemented. Though, this wasn't always the case. Direct access to memory didn't really become a thing until the late 60s, with the advent of the Memory management unit (MMU). My first experience was with the 6502, and 6510. For instance the 6510 had 64k of addressable memory, but good luck ever having all of it. Many architectures had each word loaded into a register, and you never had direct access to the memory. Those were absolute nightmares by today's standards. On Intel hardware, we had different registers for memory access. I can't remember all of them now, but they were split between the code, data and stack. At some point we ended up with two different memory models, protected and real mode. This was the biggest PIA ever. We had MS/DOS in one mode, then Windows running in a different mode. OS/2 came along, and we had a flat address space. What a novel concept. Windows NT next, and we were off, except for the addressable memory limit, which Intel resolved in one of the generations. DEC had a flat address space for almost 20 years, why was it so hard for everyone else? Legacy software. On the Amiga, which I absolutely loved, had two memory spaces. One was called FAST RAM, and the other CHIP RAM. This was a decision by Jay Minor (may he RIP). I don't quite remember the reasoning at the time, but it had to do with the cost of memory, what was available, and what could be emulated. The last conversation I had with Jay was about Direct Memory Access (DMA). He said he wished he would have invented it. We had a bus mastering system on the Amiga, provided by Motorola, so devices could read and write directly to an address. This created other challenges, as we did not have any protected memory on the Amiga. If you program decided to overwrite memory of another program, or device, well, you had to meditate. Children today are fortunate to be able to live in the land of purity. Flat address spaces, protected memory, distributed file systems. You missed the days of a sneaker net, having your hifi speaker erase your program, and the crunching, twinkle noise that came out of your floppy drive, and even hard drive if you were fortunate to have one. So to what you said about SIMD, that literally has nothing to do with shit, and malloc/free. You're talking out your ass. |