AMD64

x86-64 (also known as AMD64, x86_64, x64 and, rarely, Intel 64) is a 64-bit extension of the x86instruction set. It was announced in 1999 and first available in the AMD Opteron family in 2003. It introduces two new operating modes: 64-bit mode and compatibility mode, along with a new four-level paging mechanism. In 64-bit mode, x86-64 supports significantly larger amounts of virtual and physical memory compared to its 32-bit predecessors, allowing computer programs to utilize more memory. The architecture increases the number of general-purpose registers from 8 to 16, and extends each of the register's width (capacity) to 64 bits. Floating-point arithmetic is supported through mandatory SSE2 instructions in 64-bit mode. While registers for older floating-point implementations—the x87 and MMX—are still available, they are generally superseded by 128-bit vector registers for the SSE instruction set. These vector registers are capable of storing two double-precision, or up to four single-precision floating-point numbers, along with various integer formats. In 64-bit mode, instructions are modified to support 64-bit operands and 64-bit addressing mode. The x86-64 architecture defin