1//===--------------------- RegisterFileStatistics.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-exception
6//
7//===----------------------------------------------------------------------===//
8/// \file
9///
10/// This view collects and prints register file usage statistics.
11///
12/// Example (-mcpu=btver2):
13/// ========================
14///
15/// Register File statistics:
16/// Total number of mappings created: 6
17/// Max number of mappings used: 3
18///
19/// * Register File #1 -- FpuPRF:
20/// Number of physical registers: 72
21/// Total number of mappings created: 0
22/// Max number of mappings used: 0
23/// Number of optimizable moves: 200
24/// Number of moves eliminated: 200 (100.0%)
25/// Number of zero moves: 200 (100.0%)
26/// Max moves eliminated per cycle: 2
27///
28/// * Register File #2 -- IntegerPRF:
29/// Number of physical registers: 64
30/// Total number of mappings created: 6
31/// Max number of mappings used: 3
32//
33//===----------------------------------------------------------------------===//
34
35#ifndef LLVM_TOOLS_LLVM_MCA_REGISTERFILESTATISTICS_H
36#define LLVM_TOOLS_LLVM_MCA_REGISTERFILESTATISTICS_H
37
38#include "llvm/ADT/SmallVector.h"
39#include "llvm/MC/MCSubtargetInfo.h"
40#include "llvm/MCA/View.h"
41
42namespace llvm {
43namespace mca {
44
45class RegisterFileStatistics : public View {
46 const llvm::MCSubtargetInfo &STI;
47
48 // Used to track the number of physical registers used in a register file.
49 struct RegisterFileUsage {
50 unsigned TotalMappings;
51 unsigned MaxUsedMappings;
52 unsigned CurrentlyUsedMappings;
53 };
54
55 struct MoveEliminationInfo {
56 unsigned TotalMoveEliminationCandidates;
57 unsigned TotalMovesEliminated;
58 unsigned TotalMovesThatPropagateZero;
59 unsigned MaxMovesEliminatedPerCycle;
60 unsigned CurrentMovesEliminated;
61 };
62
63 // There is one entry for each register file implemented by the processor.
64 llvm::SmallVector<RegisterFileUsage, 4> PRFUsage;
65 llvm::SmallVector<MoveEliminationInfo, 4> MoveElimInfo;
66
67 void updateRegisterFileUsage(ArrayRef<unsigned> UsedPhysRegs);
68 void updateMoveElimInfo(const Instruction &Inst);
69
70public:
71 RegisterFileStatistics(const llvm::MCSubtargetInfo &sti);
72
73 void onCycleEnd() override;
74 void onEvent(const HWInstructionEvent &Event) override;
75 void printView(llvm::raw_ostream &OS) const override;
76 StringRef getNameAsString() const override {
77 return "RegisterFileStatistics";
78 }
79 bool isSerializable() const override { return false; }
80};
81} // namespace mca
82} // namespace llvm
83
84#endif
85

source code of llvm/tools/llvm-mca/Views/RegisterFileStatistics.h