1 //===-- InstCount.cpp - Collects the count of all instructions ------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This pass collects the count of all instructions and reports them
11 //
12 //===----------------------------------------------------------------------===//
13 
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/Pass.h"
19 #include "llvm/Support/Debug.h"
20 #include "llvm/Support/ErrorHandling.h"
21 #include "llvm/Support/raw_ostream.h"
22 using namespace llvm;
23 
24 #define DEBUG_TYPE "instcount"
25 
26 STATISTIC(TotalInsts , "Number of instructions (of all types)");
27 STATISTIC(TotalBlocks, "Number of basic blocks");
28 STATISTIC(TotalFuncs , "Number of non-external functions");
29 STATISTIC(TotalMemInst, "Number of memory instructions");
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 FunctionPass, 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 &) { ++Num##OPCODE##Inst; ++TotalInsts; }
45 
46 #include "llvm/IR/Instruction.def"
47 
48     void visitInstruction(Instruction &I) {
49       errs() << "Instruction Count does not know about " << I;
50       llvm_unreachable(nullptr);
51     }
52   public:
53     static char ID; // Pass identification, replacement for typeid
54     InstCount() : FunctionPass(ID) {
55       initializeInstCountPass(*PassRegistry::getPassRegistry());
56     }
57 
58     bool runOnFunction(Function &F) override;
59 
60     void getAnalysisUsage(AnalysisUsage &AU) const override {
61       AU.setPreservesAll();
62     }
63     void print(raw_ostream &O, const Module *M) const override {}
64 
65   };
66 }
67 
68 char InstCount::ID = 0;
69 INITIALIZE_PASS(InstCount, "instcount",
70                 "Counts the various types of Instructions", false, true)
71 
72 FunctionPass *llvm::createInstCountPass() { return new InstCount(); }
73 
74 // InstCount::run - This is the main Analysis entry point for a
75 // function.
76 //
77 bool InstCount::runOnFunction(Function &F) {
78   unsigned StartMemInsts =
79     NumGetElementPtrInst + NumLoadInst + NumStoreInst + NumCallInst +
80     NumInvokeInst + NumAllocaInst;
81   visit(F);
82   unsigned EndMemInsts =
83     NumGetElementPtrInst + NumLoadInst + NumStoreInst + NumCallInst +
84     NumInvokeInst + NumAllocaInst;
85   TotalMemInst += EndMemInsts-StartMemInsts;
86   return false;
87 }
88