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1//===--------------------- ResourcePressureView.h ---------------*- C++ -*-===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8/// \file9///10/// This file define class ResourcePressureView.11/// Class ResourcePressureView observes hardware events generated by12/// the Pipeline object and collects statistics related to resource usage at13/// instruction granularity.14/// Resource pressure information is then printed out to a stream in the15/// form of a table like the one from the example below:16///17/// Resources:18/// [0] - JALU019/// [1] - JALU120/// [2] - JDiv21/// [3] - JFPM22/// [4] - JFPU023/// [5] - JFPU124/// [6] - JLAGU25/// [7] - JSAGU26/// [8] - JSTC27/// [9] - JVIMUL28///29/// Resource pressure per iteration:30/// [0]    [1]    [2]    [3]    [4]    [5]    [6]    [7]    [8]    [9]31/// 0.00   0.00   0.00   0.00   2.00   2.00   0.00   0.00   0.00   0.0032///33/// Resource pressure by instruction:34/// [0]  [1]  [2]  [3]  [4]  [5]  [6]  [7]  [8]  [9]  Instructions:35///  -    -    -    -    -   1.00  -    -    -    -   vpermilpd  $1,    %xmm0,36///  %xmm137///  -    -    -    -   1.00  -    -    -    -    -   vaddps     %xmm0, %xmm1,38///  %xmm239///  -    -    -    -    -   1.00  -    -    -    -   vmovshdup  %xmm2, %xmm340///  -    -    -    -   1.00  -    -    -    -    -   vaddss     %xmm2, %xmm3,41///  %xmm442///43/// In this example, we have AVX code executed on AMD Jaguar (btver2).44/// Both shuffles and vector floating point add operations on XMM registers have45/// a reciprocal throughput of 1cy.46/// Each add is issued to pipeline JFPU0, while each shuffle is issued to47/// pipeline JFPU1. The overall pressure per iteration is reported by two48/// tables: the first smaller table is the resource pressure per iteration;49/// the second table reports resource pressure per instruction. Values are the50/// average resource cycles consumed by an instruction.51/// Every vector add from the example uses resource JFPU0 for an average of 1cy52/// per iteration. Consequently, the resource pressure on JFPU0 is of 2cy per53/// iteration.54///55//===----------------------------------------------------------------------===//56 57#ifndef LLVM_TOOLS_LLVM_MCA_RESOURCEPRESSUREVIEW_H58#define LLVM_TOOLS_LLVM_MCA_RESOURCEPRESSUREVIEW_H59 60#include "Views/InstructionView.h"61#include "llvm/ADT/ArrayRef.h"62#include "llvm/ADT/DenseMap.h"63#include "llvm/MC/MCInst.h"64#include "llvm/MC/MCInstPrinter.h"65#include "llvm/MC/MCSubtargetInfo.h"66#include "llvm/Support/JSON.h"67 68namespace llvm {69namespace mca {70 71/// This class collects resource pressure statistics and it is able to print72/// out all the collected information as a table to an output stream.73class ResourcePressureView : public InstructionView {74  unsigned LastInstructionIdx;75 76  // Map to quickly obtain the ResourceUsage column index from a processor77  // resource ID.78  llvm::DenseMap<unsigned, unsigned> Resource2VecIndex;79 80  struct ResourceReleaseAtCycles {81    unsigned ResourceIdx;82    ReleaseAtCycles Cycles;83  };84  using InstResourceUsage = std::vector<ResourceReleaseAtCycles>;85  std::vector<InstResourceUsage> ResourceUsage;86  InstResourceUsage CommonResourceUsage;87  unsigned NumResourceUnits;88 89  void printResourcePressurePerIter(llvm::raw_ostream &OS) const;90  void printResourcePressurePerInst(llvm::raw_ostream &OS) const;91 92public:93  ResourcePressureView(const llvm::MCSubtargetInfo &sti,94                       llvm::MCInstPrinter &Printer,95                       llvm::ArrayRef<llvm::MCInst> S);96 97  void onEvent(const HWInstructionEvent &Event) override;98  void printView(llvm::raw_ostream &OS) const override {99    printResourcePressurePerIter(OS);100    printResourcePressurePerInst(OS);101  }102  StringRef getNameAsString() const override { return "ResourcePressureView"; }103  json::Value toJSON() const override;104};105} // namespace mca106} // namespace llvm107 108#endif109