1 //===-- InstCount.cpp - Collects the count of all instructions ------------===//
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 pass collects the count of all instructions and reports them
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "llvm/Analysis/InstCount.h"
14 #include "llvm/ADT/Statistic.h"
15 #include "llvm/Analysis/Passes.h"
16 #include "llvm/IR/Function.h"
17 #include "llvm/IR/InstVisitor.h"
18 #include "llvm/InitializePasses.h"
19 #include "llvm/Pass.h"
20 #include "llvm/Support/Debug.h"
21 #include "llvm/Support/ErrorHandling.h"
22 #include "llvm/Support/raw_ostream.h"
23 using namespace llvm;
24 
25 #define DEBUG_TYPE "instcount"
26 
27 STATISTIC(TotalInsts, "Number of instructions (of all types)");
28 STATISTIC(TotalBlocks, "Number of basic blocks");
29 STATISTIC(TotalFuncs, "Number of non-external functions");
30 
31 #define HANDLE_INST(N, OPCODE, CLASS)                                          \
32   STATISTIC(Num##OPCODE##Inst, "Number of " #OPCODE " insts");
33 
34 #include "llvm/IR/Instruction.def"
35 
36 namespace {
37 class InstCount : public InstVisitor<InstCount> {
38   friend class InstVisitor<InstCount>;
39 
40   void visitFunction(Function &F) { ++TotalFuncs; }
41   void visitBasicBlock(BasicBlock &BB) { ++TotalBlocks; }
42 
43 #define HANDLE_INST(N, OPCODE, CLASS)                                          \
44   void visit##OPCODE(CLASS &) {                                                \
45     ++Num##OPCODE##Inst;                                                       \
46     ++TotalInsts;                                                              \
47   }
48 
49 #include "llvm/IR/Instruction.def"
50 
51   void visitInstruction(Instruction &I) {
52     errs() << "Instruction Count does not know about " << I;
53     llvm_unreachable(nullptr);
54   }
55 };
56 } // namespace
57 
58 PreservedAnalyses InstCountPass::run(Function &F,
59                                      FunctionAnalysisManager &FAM) {
60   LLVM_DEBUG(dbgs() << "INSTCOUNT: running on function " << F.getName()
61                     << "\n");
62   InstCount().visit(F);
63 
64   return PreservedAnalyses::all();
65 }
66 
67 namespace {
68 class InstCountLegacyPass : public FunctionPass {
69 public:
70   static char ID; // Pass identification, replacement for typeid
71   InstCountLegacyPass() : FunctionPass(ID) {
72     initializeInstCountLegacyPassPass(*PassRegistry::getPassRegistry());
73   }
74 
75   bool runOnFunction(Function &F) override {
76     LLVM_DEBUG(dbgs() << "INSTCOUNT: running on function " << F.getName()
77                       << "\n");
78     InstCount().visit(F);
79     return false;
80   };
81 
82   void getAnalysisUsage(AnalysisUsage &AU) const override {
83     AU.setPreservesAll();
84   }
85 
86   void print(raw_ostream &O, const Module *M) const override {}
87 };
88 } // namespace
89 
90 char InstCountLegacyPass::ID = 0;
91 INITIALIZE_PASS(InstCountLegacyPass, "instcount",
92                 "Counts the various types of Instructions", false, true)
93 
94 FunctionPass *llvm::createInstCountPass() { return new InstCountLegacyPass(); }
95