Apple 编程中如何普遍使用整数除法？
我正在阅读对 LLVM 和 Swift 的作者 Chris Lattner 的有趣采访，并注意到一个非常奇怪的说法：
其他事情是，Apple 会定期向其 CPU 添加新指令 [11:00]。历史上的一个例子是它推出的名为“Swift”的芯片，这是第一款内部设计的 32 位 ARM 芯片。如果我没记错的话，这是 iPhone 5。
在这个芯片中，他们添加了整数除法指令。在此之前的所有芯片都不具备在硬件中进行整数除法的能力：您必须实际对其进行开放代码，并且有一个库函数可以做到这一点。 [11:30] 这一点，以及他们添加的其他一些指令，是一个相当大的问题，并且被广泛使用
现在这令人惊讶。据我了解，几乎不需要整数除法。我见过的可以使用它的情况分为以下几类：
除以 2 的幂。改为右移。
除以整数常量。而是乘以倒数。 （这是违反直觉的，但确实这在所有情况下都有效。）
作为实数算术近似值的定点。请改用浮点数。
定点，适用于在具有不同 CPU 架构的计算机上点对点运行的多人游戏，并且需要每台计算机就最后一位的结果达成一致。好的，但据我了解，iPhone 上的多人游戏不使用这种点对点设计。
渲染 3D 纹理。请改为在 GPU 上执行此操作。
当浮点在硬件中可用后，我从未见过需要以很高的频率进行整数除法的工作负载。
我缺少什么？整数除法在 Apple 设备上的用途如此频繁，以至于值得将其添加为 CPU 指令？
I was reading an interesting interview with Chris Lattner, author of LLVM and Swift, and noticed a very curious claim:
Other things are that Apple does periodically add new instructions [11:00] to its CPUs. One example of this historically was the hilariously named “Swift” chip that it launched which was the first designed in-house 32-bit ARM chip. This was the iPhone 5, if I recall.
In this chip, they added an integer-divide instruction. All of the chips before that didn’t have the ability to integer-divide in hardware: you had to actually open-code it, and there was a library function to do that. [11:30] That, and a few other instructions they added, were a pretty big deal and used pervasively
Now that is surprising. As I understand it, integer divide is almost never needed. The cases I've seen where it could be used, fall into a few categories:
Dividing by a power of two. Shift right instead.
Dividing by an integer constant. Multiply by the reciprocal instead. (It's counterintuitive but true that this works in all cases.)
Fixed point as an approximation of real number arithmetic. Use floating point instead.
Fixed point, for multiplayer games that run peer-to-peer across computers with different CPU architectures and need each computer to agree on the results down to the last bit. Okay, but as I understand it, multiplayer games on iPhone don't use that kind of peer-to-peer design.
Rendering 3D textures. Do that on the GPU instead.
After floating point became available in hardware, I've never seen a workload that needed to do integer divide with significant frequency.
What am I missing? What was integer divide used for on Apple devices, so frequently that it was considered worth adding as a CPU instruction?
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