X86 Assembly/Intrinsic Data Types
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[edit] Integer
The integer represents a number. Under the 8086 architecture, it originally came in 8-bit and 16-bit sizes, which served the most basic operations. Later, starting with the 80386 , the data bus was expanded to support 32-bit operations and thus allow operations on integers of that size. The newest systems under the x86 architecture support 64-bit instructions, however this requires a 64-bit operating system for optimal effect.
Some assembly instructions behave slightly differently in regards to the sign bit; as such, there is a minor distinction between signed and unsigned integers.
[edit] Floating point Numbers
Originally, floating point was not part of the main processor, requiring the use of emulating software. However, there were floating point coprocessors that allowed operations on this data-type, and starting with the 486DX, were integrated directly with the CPU.
As such, floating point operations are not necessarily compatible with all processors - if you need to perform this type of arithmetic, you may want to use a software library as a backup code path.
