X86 opcode table. 0/1/2/4 0/1/2/4 D D G M MM G G Main Opcode bits Direction bit Operand...

X86 opcode table. 0/1/2/4 0/1/2/4 D D G M MM G G Main Opcode bits Direction bit Operand length bit r/m field B B B Base field Index field Scale field Register/Opcode modifier, defined by primary opcode Addressing mode (scale, index, base) This is an HTML-ized version of the opcode map for the 8086 processor. It is arranged such that each axis of the table represents an upper or lower nibble, which combined form the full byte of the opcode. An opcode table (also called an opcode matrix) is a visual representation of all opcodes in an instruction set. x86 opcode map Legend The opcode maps are shown as collapsible 16x16 tables, with empty maps omitted. 0/1/2/4 0/1/2/4 D D G M MM G G Main Opcode bits Direction bit Operand length bit r/m field B B B Base field Index field Scale field Register/Opcode modifier, defined by primary opcode Addressing mode (scale, index, base) Opcode Table Reference: Full Expanded Opcode Listings with Instruction Variants In the architecture of an x86-64 assembler, the opcode table forms the backbone for instruction encoding and decoding. Last updated 2024-02-18. Opcode The x86-64 instruction set defines many opcodes and many ways to encode them, depending on several factors. Feb 18, 2024 · Derived from the December 2023 version of the Intel® 64 and IA-32 Architectures Software Developer’s Manual. A plain-text version - easily parsable by software - is also available. Clicking the X mark or outside the popup region or pressing the Escape key closes the popup. xpj airxw kinrzv mnid gtflcy taxvzxs qmmtp udxovc dmh zsw