原帖由 PCINLIFEboy 于 2006-6-14 23:49 发表
IA64的EPIC是VLIW的一个变种，也算是RISC。
IA64当然是，Intel不愿意这么叫吧．
RISC (Reduced Instruction Set Computing) is the concept of reducing an instruction sets' complexity (modernizing your instruction sets' design) so that you can use the gates (extra space) for things that make the instructions go faster with techniques like adding cache (fast memory), pipelining (breaking the instructions down into sub parts, and preprocessing as much as possible), superscalar (executing instructions in parallel), a load-store architecture (the computer can either load or store, and not try to do many things or both in the same instruction), adding more registers, and adding bits that can help with things like branch-prediction and other things -- all to make the machine faster.
VLIW (Very-Long Instruction-Word) is a form of RISC, where you can "group" RISC instructions into a bigger "word" -- so big it called a Very-Long Instruction Word -- then it executes all the instructions in parallel. It is still a TYPE of RISC processor -- but it is a unique type. Like Dogs are Mammals -- VLIW is usually a RISC chip.
EPIC (Explicit Parallel Instruction Computing) is a form of VLIW, and RISC, with a few additions. Basically, it uses VLIW instructions, but has some "hints" embedded in the instruction set to help with the parallelism and to reduce branching (with predication), and it has a few more registers, and some other minor changes. It is still a TYPE of RISC processor, and a type of VLIW processor. Like Collies are Dogs, and Dogs are Mammals -- EPIC is VLIW, and VLIW is RISC. |
IP卡
狗仔卡
发表于 2006-6-14 23:19
显身卡