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x86 Assembly


Category Instructions
Data transfer mov, cmovcc, push, pop, pushad, popad, xchg, xadd, movsx, movzx
Data comparison cmp, cmpxchg, cmpxchg8b
Data conversion cbw, cwde, cwd, cdq, bswap, movbe, xlatb
Binary arithmetic add, adc, sub, sbb, imul, mul, idiv, div, inc, dec, neg, daa, das, aaa, aas, aam, aad
Logical and, or, xor, not, test
Rotate and shift rcl, rcr, rol, ror, sal/shl, sar, shr, shld, shrd
Byte set and bit strings setcc, bt, bts, btr, btc, bsf, bsr
String cmpsb, cmpsw, cmpsd, lodsb, lodsw, lodsd, movsb, movsw, movsd, scasb, scasw, scasd, stosb, stosw, stosd, rep, repe, repz, repne, repnz
Flag manipulation clc, stc, cmc, std, cld, lahf, sahf, pushfd, popfd
Control transfer jmp, jcc, call, ret, enter, leave, jecxz, loop, loope, loopz, loopne, loopnz
Miscellaneous bound, lea, nop, cpuid

Data Types

Data types supported by the x86 platform:

Data Type Bits
Byte 8
Word 16
Doubleword 32
Quadword 64
Quintword 80
Double Quadword 128
Quad Quadword 256


Year CPU Microarchitecture Features
1985 80386 - 32-bit registers and data types
- flat memory model option
- 4GB logical address space
- paged virtual memory
- separate 80387 FPU
1989 80486 - on-chip memory caches
- optimized instructions
- integrated x87 FPU
1993 Pentium P5 - dual-instruction execution pipeline
- 64-bit external data bus
- separate on-chip code and data caches
- MMX - the technology supporting SIMD on packed integers using 64-bit registers
1995 Pentium Pro P6 - three-way superscalar design
- support for out-of-order instruction execution
- improved branch-prediction algorithms
- speculative instruction execution
1997 Pentium II P6
1999 Pentium III P6 SSE SIMD extensions:
- 128-bit registers
- packed single-precision floating-point arithmetic
2000 Pentium 4 Netburst SSE2 SIMD extensions:
- packed double-precision (64-bit) values
- 128-bit SSE registers can be used for packed integer calculations and scalar floating-point operations
2004 Pentium 4
90 nm and smaller
Netburst SSE3 SIMD extensions:
- hyper-threading technology
- packed integer and packed floating-point instructions
2006 Core 2 Duo
Core 2 Quad
Xeon 3000/5000
Core - improved performance
- reduced power consumption
- no hyper-threading
SSSE3. SSE4.1:
- new packed integer and floating-point instructions
2008 Core i3,i5,i7
(1st generation)
Xeon 7000
Nehalem - reintroduction of hyper-threading
- new accelerator instructions
- instructions for text-string processing
2011 Core i3,i5,i7
(2nd and 3rd generations)
Xeon E3/E5/E7
Sandy Bridge New SIMD technology AVX:
- 256-bit regsiters for packed floating-point operations (single- and double-precision)
- three-operand instruction syntax
2013 Core i3,i5,i7
(4th generation)
Xeon E3 (v3)
Haswell FMS (fuse-multiply-add) operations
- 256-bit registers for packed integer operations
- enhanced data transfer capabilities: broadcast, gather, permute instructions


  • Microarchitecture defines the organization of a processor's internal components, including registers, execution units, instruction pipelines, data buses, and memory caches.
  • In the three-way superscalar design, the processor is able to decode, dispatch, and execute three distinct instructions during each clock cycle.
  • The address of properly-aligned data type is divisible by its size in bytes.
  • SIMD - Single Instruction Multiple Data
notes/assembly.1560479345.txt.gz · Last modified: 2019/06/13 by leszek