1 //===- FunctionPropertiesAnalysis.cpp - Function Properties Analysis ------===//
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 //
9 // This file defines the FunctionPropertiesInfo and FunctionPropertiesAnalysis
10 // classes used to extract function properties.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "llvm/Analysis/FunctionPropertiesAnalysis.h"
15 #include "llvm/IR/Instructions.h"
16 
17 using namespace llvm;
18 
19 FunctionPropertiesInfo
getFunctionPropertiesInfo(const Function & F,const LoopInfo & LI)20 FunctionPropertiesInfo::getFunctionPropertiesInfo(const Function &F,
21                                                   const LoopInfo &LI) {
22 
23   FunctionPropertiesInfo FPI;
24 
25   FPI.Uses = ((!F.hasLocalLinkage()) ? 1 : 0) + F.getNumUses();
26 
27   for (const auto &BB : F) {
28     ++FPI.BasicBlockCount;
29 
30     if (const auto *BI = dyn_cast<BranchInst>(BB.getTerminator())) {
31       if (BI->isConditional())
32         FPI.BlocksReachedFromConditionalInstruction += BI->getNumSuccessors();
33     } else if (const auto *SI = dyn_cast<SwitchInst>(BB.getTerminator())) {
34       FPI.BlocksReachedFromConditionalInstruction +=
35           (SI->getNumCases() + (nullptr != SI->getDefaultDest()));
36     }
37 
38     for (const auto &I : BB) {
39       if (auto *CS = dyn_cast<CallBase>(&I)) {
40         const auto *Callee = CS->getCalledFunction();
41         if (Callee && !Callee->isIntrinsic() && !Callee->isDeclaration())
42           ++FPI.DirectCallsToDefinedFunctions;
43       }
44       if (I.getOpcode() == Instruction::Load) {
45         ++FPI.LoadInstCount;
46       } else if (I.getOpcode() == Instruction::Store) {
47         ++FPI.StoreInstCount;
48       }
49     }
50     // Loop Depth of the Basic Block
51     int64_t LoopDepth;
52     LoopDepth = LI.getLoopDepth(&BB);
53     if (FPI.MaxLoopDepth < LoopDepth)
54       FPI.MaxLoopDepth = LoopDepth;
55   }
56   FPI.TopLevelLoopCount += llvm::size(LI);
57   return FPI;
58 }
59 
print(raw_ostream & OS) const60 void FunctionPropertiesInfo::print(raw_ostream &OS) const {
61   OS << "BasicBlockCount: " << BasicBlockCount << "\n"
62      << "BlocksReachedFromConditionalInstruction: "
63      << BlocksReachedFromConditionalInstruction << "\n"
64      << "Uses: " << Uses << "\n"
65      << "DirectCallsToDefinedFunctions: " << DirectCallsToDefinedFunctions
66      << "\n"
67      << "LoadInstCount: " << LoadInstCount << "\n"
68      << "StoreInstCount: " << StoreInstCount << "\n"
69      << "MaxLoopDepth: " << MaxLoopDepth << "\n"
70      << "TopLevelLoopCount: " << TopLevelLoopCount << "\n\n";
71 }
72 
73 AnalysisKey FunctionPropertiesAnalysis::Key;
74 
75 FunctionPropertiesInfo
run(Function & F,FunctionAnalysisManager & FAM)76 FunctionPropertiesAnalysis::run(Function &F, FunctionAnalysisManager &FAM) {
77   return FunctionPropertiesInfo::getFunctionPropertiesInfo(
78       F, FAM.getResult<LoopAnalysis>(F));
79 }
80 
81 PreservedAnalyses
run(Function & F,FunctionAnalysisManager & AM)82 FunctionPropertiesPrinterPass::run(Function &F, FunctionAnalysisManager &AM) {
83   OS << "Printing analysis results of CFA for function "
84      << "'" << F.getName() << "':"
85      << "\n";
86   AM.getResult<FunctionPropertiesAnalysis>(F).print(OS);
87   return PreservedAnalyses::all();
88 }
89