x64 Architecture - x86 Architecture - x86-64 - x86_64

x64 Architecture - x86 Architecture - x86-64 - x86_64

1. uname - print system information

Print certain system information. With no OPTION, same as -s.

-a, --all
print all information, in the following order, except omit -p and -i if unknown:

yongqiang@yongqiang:~$ uname -a
Linux yongqiang 4.4.0-17763-Microsoft #864-Microsoft Thu Nov 07 15:22:00 PST 2019 x86_64 x86_64 x86_64 GNU/Linux
yongqiang@yongqiang:~$

-m, --machine
print the machine hardware name

yongqiang@yongqiang:~$ uname -m
x86_64
yongqiang@yongqiang:~$

-p, --processor
print the processor type (non-portable)

yongqiang@yongqiang:~$ uname -p
x86_64
yongqiang@yongqiang:~$

-i, --hardware-platform
print the hardware platform (non-portable)

yongqiang@yongqiang:~$ uname -i
x86_64
yongqiang@yongqiang:~$

2. x64 Architecture

The x64 architecture is a backwards-compatible extension of x86. It provides a legacy 32-bit mode, which is identical to x86, and a new 64-bit mode.
x64 体系结构是 x86 的向后兼容的扩展。它提供旧的 32 位模式 (这就相当于 x86)，以及新的 64 位模式。

The term x64 includes both AMD 64 and Intel64. The instruction sets are close to identical.
术语 x64 包括 AMD 64 和 Intel64。指令集即将于完全相同。

3. x86 Architecture

The Intel x86 processor uses complex instruction set computer (CISC) architecture, which means there is a modest number of special-purpose registers instead of large quantities of general-purpose registers. It also means that complex special-purpose instructions will predominate.
Intel x86 处理器使用复杂指令集计算机 (CISC) 体系结构，这意味着有适度数量的专用寄存器，而不是大量通用寄存器。这也意味着复杂的特殊用途指令集将主流。

The x86 processor traces its heritage at least as far back as the 8-bit Intel 8080 processor. Many peculiarities in the x86 instruction set are due to the backward compatibility with that processor (and with its Zilog Z-80 variant).
x86 处理器的历史至少可以追溯到 8 位 Intel 8080 处理器。x86 指令集的许多特性是由于与该处理器 (及其 Zilog Z-80 变体) 的向后兼容性。

Microsoft Win32 uses the x86 processor in 32-bit flat mode.
Microsoft Win32 在 32 位平面模式下使用 x86 处理器。

peculiarity [pɪˌkjuːliˈærəti]：n. 特点，特性，怪癖，性状

3. x86-64

x86-64 is an extension of the x86 instruction set.

x86-64 (64-bit extended，x64：64位拓展) 是 x86 架构的 64 位拓展，向后兼容于 16 位及 32 位的 x86 架构。x64 于 1999 年由 AMD 设计，AMD 首次公开 64 位指令集以扩展给 x86，称为 AMD64。

英特尔称之为 Intel 64，在之前曾使用过 Clackamas Technology (CT)、IA-32e 及 EM64T。

苹果公司和 RPM 包管理员以 x86-64 或 x86_64 称呼 64 位架构。甲骨文公司及 Microsoft 称之为 x64。Linux 发行版则使用 x64-64，32位版本则称为 i386 (i486/586/686)，Arch Linux 用 x86_64 称呼 64 位架构。

References

https://docs.microsoft.com/en-us/windows-hardware/drivers/debugger/x64-architecture