en Copyright 2015 Java http://172.16.0.5:8080/history/llvm-project-15.0.7/llvm/lib/MCA/Stages/MicroOpQueueStage.cpp#e074ac60 [MCA] Add an experimental MicroOpQueue stage.This patch adds an experimental stage named MicroOpQueueStage.MicroOpQueueStage can be used to simulate a hardware micro-op queue (basically,a decoupling queue between 'decode' and 'dispatch'). Users can specify a queuesize, as well as a optional MaxIPC (which - in the absence of a "Decoders" stage- can be used to simulate a different throughput from the decoders).This stage is added to the default pipeline between the EntryStage and theDispatchStage only if PipelineOption::MicroOpQueue is different than zero. Bydefault, llvm-mca sets PipelineOption::MicroOpQueue to the value of hidden flag-micro-op-queue-size.Throughput from the decoder can be simulated via another hidden flag named-decoder-throughput. That flag allows us to quickly experiment with differentfrontend throughputs. For targets that declare a loop buffer, flag-decoder-throughput allows users to do multiple runs, each time simulating adifferent throughput from the decoders.This stage can/will be extended in future. For example, we could add a "bufferfull" event to notify bottlenecks caused by backpressure. flag-decoder-throughput would probably go away if in future we delegate to anotherstage (DecoderStage?) the simulation of a (potentially variable) throughput fromthe decoders. For now, flag -decoder-throughput is "good enough" to run somesimple experiments.Differential Revision: https://reviews.llvm.org/D59928llvm-svn: 357248 List of files: /llvm-project-15.0.7/llvm/lib/MCA/Stages/MicroOpQueueStage.cpp Fri, 29 Mar 2019 12:15:37 +0000 Andrea Di Biagio <Andrea_DiBiagio@sn.scee.net>