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A register file is an array of processor registers in a central processing unit (CPU). Modern integrated circuit-based register files are usually implemented by way of fast static RAMs with multiple ports. Such RAMs are distinguished by having dedicated read and write ports, whereas ordinary multiported SRAMs will usually read and write through the same ports. The instruction set architecture of a CPU will almost always define a set of registers which are used to stage data between memory and the functional units on the chip. In simpler CPUs, these ''architectural registers'' correspond one-for-one to the entries in a physical register file within the CPU. More complicated CPUs use register renaming, so that the mapping of which physical entry stores a particular architectural register changes dynamically during execution. The register file is part of the architecture and visible to the programmer, as opposed to the concept of transparent caches. == Register bank switching == Register files may be clubbed together as register banks.〔 Wikibooks: Microprocessor Design/Register File#Register Bank. 〕 Some processors have several register banks. ARM processors use ARM register banks for fast interrupt request. x86 processor use context switch and fast interrupt for switch between instruction, decoder, GPRs and register files (if they are more than one) before the instruction is issued, but this is only existing on processor that support superscalar. However context switch is a totally different mechanism to ARM's register bank within the registers. The MODCOMP and the later 8051-compatible processors use bits in the program status word to select the currently active register bank. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「register file」の詳細全文を読む スポンサード リンク
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