Line data    Source code

       1             : //===- CountingFunctionInserter.cpp - Insert mcount-like function calls ---===//
       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             : // Insert calls to counter functions, such as mcount, intended to be called
      11             : // once per function, at the beginning of each function.
      12             : //
      13             : //===----------------------------------------------------------------------===//
      14             : 
      15             : #include "llvm/Analysis/GlobalsModRef.h"
      16             : #include "llvm/CodeGen/Passes.h"
      17             : #include "llvm/IR/Function.h"
      18             : #include "llvm/IR/Instructions.h"
      19             : #include "llvm/IR/Module.h"
      20             : #include "llvm/IR/Type.h"
      21             : #include "llvm/Pass.h"
      22             : using namespace llvm;
      23             : 
      24             : namespace {
      25       33642 :   struct CountingFunctionInserter : public FunctionPass {
      26             :     static char ID; // Pass identification, replacement for typeid
      27       33848 :     CountingFunctionInserter() : FunctionPass(ID) {
      28       16924 :       initializeCountingFunctionInserterPass(*PassRegistry::getPassRegistry());
      29             :     }
      30             :     
      31       16887 :     void getAnalysisUsage(AnalysisUsage &AU) const override {
      32       16887 :       AU.addPreserved<GlobalsAAWrapperPass>();
      33       16887 :     }
      34             : 
      35      143178 :     bool runOnFunction(Function &F) override {
      36             :       std::string CountingFunctionName =
      37      572712 :         F.getFnAttribute("counting-function").getValueAsString();
      38      143178 :       if (CountingFunctionName.empty())
      39             :         return false;
      40             : 
      41           5 :       Type *VoidTy = Type::getVoidTy(F.getContext());
      42             :       Constant *CountingFn =
      43          15 :         F.getParent()->getOrInsertFunction(CountingFunctionName,
      44           5 :                                            VoidTy);
      45          25 :       CallInst::Create(CountingFn, "", &*F.begin()->getFirstInsertionPt());
      46           5 :       return true;
      47             :     }
      48             :   };
      49             :   
      50             :   char CountingFunctionInserter::ID = 0;
      51             : }
      52             : 
      53      291852 : INITIALIZE_PASS(CountingFunctionInserter, "cfinserter", 
      54             :                 "Inserts calls to mcount-like functions", false, false)
      55             : 
      56             : //===----------------------------------------------------------------------===//
      57             : //
      58             : // CountingFunctionInserter - Give any unnamed non-void instructions "tmp" names.
      59             : //
      60       16923 : FunctionPass *llvm::createCountingFunctionInserterPass() {
      61       33846 :   return new CountingFunctionInserter();
      62             : }