What is Very long instruction word?
'''Very Long Instruction Word''' or '''VLIW''' which refers to a [[Central processing unit|CPU]] [[Computer architecture|architecture]] designed to take advantage of [[instruction level parallelism]] (ILP) but at minimum level of [[Computer hardware|hardware]] complexities. ( Alternatively, '''Variable Length Instruction Word''' or '''VLIW''' a refers to a [[Central processing unit|CPU]] instruction ( [[instruction set]] ) designed to load ( or copy ) a literal value count of inline [[Machine code]] to the on-chip RAM for higher speed [[Central processing unit|CPU]] decoding. ) A processor that executes every [[Instruction (computer science)|instruction]] one after the other (i.e. a non-[[Instruction pipelining|pipelined]] scalar architecture) may use processor resources [[Energy efficiency|inefficiently]], leading to poor [[Computer performance|performance]]. The performance can be improved by using [[Microarchitecture|micro-architectural]] [[design]] [[technique]]s that use [[instruction level parallelism|ILP]] including: *[[Instruction pipelining]] where the execution of multiple [[Instruction (computer science)|instructions]] can be partially [[Overlap|overlapped]]; where each instructions is divided into series of sub-steps ([[Technical terminology|termed]]: [[micro-operation]]s). *[[Superscalar]] execution in which multiple [[execution unit]]s are used to execute multiple [[Instruction (computer science)|instructions]] in parallel. *[[Out-of-order execution]] where [[Instruction (computer science)|instructions]] execute in any order but without violating [[Data dependency|data dependencies]]. *[[Register renaming]] which is a [[technique]] used to avoid unnecessary [[serialization]] of program [[Instruction (computer science)|instructions]] caused by the reuse of registers by those instructions, in order to enable out-of-order execution. *[[Speculative execution]] which allow the execution of complete [[Instruction (computer science)|instructions]] or parts of instructions before being sure whether this