-//===- RaiseAllocations.cpp - Convert %malloc & %free calls to insts ------===//
-//
+//===- RaiseAllocations.cpp - Convert @malloc & @free calls to insts ------===//
+//
// The LLVM Compiler Infrastructure
//
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
-//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
//===----------------------------------------------------------------------===//
//
// This file defines the RaiseAllocations pass which convert malloc and free
//
//===----------------------------------------------------------------------===//
+#define DEBUG_TYPE "raiseallocs"
#include "llvm/Transforms/IPO.h"
-#include "llvm/Module.h"
+#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
-#include "llvm/iMemory.h"
-#include "llvm/iTerminators.h"
-#include "llvm/iOther.h"
+#include "llvm/Module.h"
+#include "llvm/Instructions.h"
#include "llvm/Pass.h"
#include "llvm/Support/CallSite.h"
-#include "Support/Statistic.h"
+#include "llvm/Support/Compiler.h"
+#include "llvm/ADT/Statistic.h"
+#include <algorithm>
+using namespace llvm;
-namespace llvm {
+STATISTIC(NumRaised, "Number of allocations raised");
namespace {
- Statistic<> NumRaised("raiseallocs", "Number of allocations raised");
-
- // RaiseAllocations - Turn %malloc and %free calls into the appropriate
+ // RaiseAllocations - Turn @malloc and @free calls into the appropriate
// instruction.
//
- class RaiseAllocations : public Pass {
+ class VISIBILITY_HIDDEN RaiseAllocations : public ModulePass {
Function *MallocFunc; // Functions in the module we are processing
Function *FreeFunc; // Initialized by doPassInitializationVirt
public:
- RaiseAllocations() : MallocFunc(0), FreeFunc(0) {}
-
+ static char ID; // Pass identification, replacement for typeid
+ RaiseAllocations()
+ : ModulePass((intptr_t)&ID), MallocFunc(0), FreeFunc(0) {}
+
// doPassInitialization - For the raise allocations pass, this finds a
// declaration for malloc and free if they exist.
//
void doInitialization(Module &M);
-
+
// run - This method does the actual work of converting instructions over.
//
- bool run(Module &M);
+ bool runOnModule(Module &M);
};
-
- RegisterOpt<RaiseAllocations>
+
+ char RaiseAllocations::ID = 0;
+ RegisterPass<RaiseAllocations>
X("raiseallocs", "Raise allocations from calls to instructions");
} // end anonymous namespace
// createRaiseAllocationsPass - The interface to this file...
-Pass *createRaiseAllocationsPass() {
+ModulePass *llvm::createRaiseAllocationsPass() {
return new RaiseAllocations();
}
// free functions. If this is the case, grab the method pointers that the
// module is using.
//
-// Lookup %malloc and %free in the symbol table, for later use. If they don't
+// Lookup @malloc and @free in the symbol table, for later use. If they don't
// exist, or are not external, we do not worry about converting calls to that
// function into the appropriate instruction.
//
void RaiseAllocations::doInitialization(Module &M) {
- const FunctionType *MallocType = // Get the type for malloc
- FunctionType::get(PointerType::get(Type::SByteTy),
- std::vector<const Type*>(1, Type::ULongTy), false);
-
- const FunctionType *FreeType = // Get the type for free
- FunctionType::get(Type::VoidTy,
- std::vector<const Type*>(1, PointerType::get(Type::SByteTy)),
- false);
// Get Malloc and free prototypes if they exist!
- MallocFunc = M.getFunction("malloc", MallocType);
- FreeFunc = M.getFunction("free" , FreeType);
-
- // Check to see if the prototype is wrong, giving us sbyte*(uint) * malloc
- // This handles the common declaration of: 'void *malloc(unsigned);'
- if (MallocFunc == 0) {
- MallocType = FunctionType::get(PointerType::get(Type::SByteTy),
- std::vector<const Type*>(1, Type::UIntTy), false);
- MallocFunc = M.getFunction("malloc", MallocType);
- }
-
- // Check to see if the prototype is missing, giving us sbyte*(...) * malloc
- // This handles the common declaration of: 'void *malloc();'
- if (MallocFunc == 0) {
- MallocType = FunctionType::get(PointerType::get(Type::SByteTy),
- std::vector<const Type*>(), true);
- MallocFunc = M.getFunction("malloc", MallocType);
- }
-
- // Check to see if the prototype was forgotten, giving us void (...) * free
- // This handles the common forward declaration of: 'void free();'
- if (FreeFunc == 0) {
- FreeType = FunctionType::get(Type::VoidTy, std::vector<const Type*>(),true);
- FreeFunc = M.getFunction("free", FreeType);
+ MallocFunc = M.getFunction("malloc");
+ if (MallocFunc) {
+ const FunctionType* TyWeHave = MallocFunc->getFunctionType();
+
+ // Get the expected prototype for malloc
+ const FunctionType *Malloc1Type =
+ FunctionType::get(PointerType::getUnqual(Type::Int8Ty),
+ std::vector<const Type*>(1, Type::Int64Ty), false);
+
+ // Chck to see if we got the expected malloc
+ if (TyWeHave != Malloc1Type) {
+ // Check to see if the prototype is wrong, giving us sbyte*(uint) * malloc
+ // This handles the common declaration of: 'void *malloc(unsigned);'
+ const FunctionType *Malloc2Type =
+ FunctionType::get(PointerType::getUnqual(Type::Int8Ty),
+ std::vector<const Type*>(1, Type::Int32Ty), false);
+ if (TyWeHave != Malloc2Type) {
+ // Check to see if the prototype is missing, giving us
+ // sbyte*(...) * malloc
+ // This handles the common declaration of: 'void *malloc();'
+ const FunctionType *Malloc3Type =
+ FunctionType::get(PointerType::getUnqual(Type::Int8Ty),
+ std::vector<const Type*>(), true);
+ if (TyWeHave != Malloc3Type)
+ // Give up
+ MallocFunc = 0;
+ }
+ }
}
- // One last try, check to see if we can find free as 'int (...)* free'. This
- // handles the case where NOTHING was declared.
- if (FreeFunc == 0) {
- FreeType = FunctionType::get(Type::IntTy, std::vector<const Type*>(),true);
- FreeFunc = M.getFunction("free", FreeType);
+ FreeFunc = M.getFunction("free");
+ if (FreeFunc) {
+ const FunctionType* TyWeHave = FreeFunc->getFunctionType();
+
+ // Get the expected prototype for void free(i8*)
+ const FunctionType *Free1Type = FunctionType::get(Type::VoidTy,
+ std::vector<const Type*>(1, PointerType::getUnqual(Type::Int8Ty)), false);
+
+ if (TyWeHave != Free1Type) {
+ // Check to see if the prototype was forgotten, giving us
+ // void (...) * free
+ // This handles the common forward declaration of: 'void free();'
+ const FunctionType* Free2Type = FunctionType::get(Type::VoidTy,
+ std::vector<const Type*>(),true);
+
+ if (TyWeHave != Free2Type) {
+ // One last try, check to see if we can find free as
+ // int (...)* free. This handles the case where NOTHING was declared.
+ const FunctionType* Free3Type = FunctionType::get(Type::Int32Ty,
+ std::vector<const Type*>(),true);
+
+ if (TyWeHave != Free3Type) {
+ // Give up.
+ FreeFunc = 0;
+ }
+ }
+ }
}
// Don't mess with locally defined versions of these functions...
- if (MallocFunc && !MallocFunc->isExternal()) MallocFunc = 0;
- if (FreeFunc && !FreeFunc->isExternal()) FreeFunc = 0;
+ if (MallocFunc && !MallocFunc->isDeclaration()) MallocFunc = 0;
+ if (FreeFunc && !FreeFunc->isDeclaration()) FreeFunc = 0;
}
// run - Transform calls into instructions...
//
-bool RaiseAllocations::run(Module &M) {
+bool RaiseAllocations::runOnModule(Module &M) {
// Find the malloc/free prototypes...
doInitialization(M);
// First, process all of the malloc calls...
if (MallocFunc) {
std::vector<User*> Users(MallocFunc->use_begin(), MallocFunc->use_end());
+ std::vector<Value*> EqPointers; // Values equal to MallocFunc
while (!Users.empty()) {
- if (Instruction *I = dyn_cast<Instruction>(Users.back())) {
+ User *U = Users.back();
+ Users.pop_back();
+
+ if (Instruction *I = dyn_cast<Instruction>(U)) {
CallSite CS = CallSite::get(I);
- if (CS.getInstruction() && CS.getCalledFunction() == MallocFunc &&
- CS.arg_begin() != CS.arg_end()) {
+ if (CS.getInstruction() && !CS.arg_empty() &&
+ (CS.getCalledFunction() == MallocFunc ||
+ std::find(EqPointers.begin(), EqPointers.end(),
+ CS.getCalledValue()) != EqPointers.end())) {
+
Value *Source = *CS.arg_begin();
-
+
// If no prototype was provided for malloc, we may need to cast the
// source size.
- if (Source->getType() != Type::UIntTy)
- Source = new CastInst(Source, Type::UIntTy, "MallocAmtCast", I);
-
- std::string Name(I->getName()); I->setName("");
- MallocInst *MI = new MallocInst(Type::SByteTy, Source, Name, I);
+ if (Source->getType() != Type::Int32Ty)
+ Source =
+ CastInst::createIntegerCast(Source, Type::Int32Ty, false/*ZExt*/,
+ "MallocAmtCast", I);
+
+ MallocInst *MI = new MallocInst(Type::Int8Ty, Source, "", I);
+ MI->takeName(I);
I->replaceAllUsesWith(MI);
// If the old instruction was an invoke, add an unconditional branch
Changed = true;
++NumRaised;
}
+ } else if (GlobalValue *GV = dyn_cast<GlobalValue>(U)) {
+ Users.insert(Users.end(), GV->use_begin(), GV->use_end());
+ EqPointers.push_back(GV);
+ } else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(U)) {
+ if (CE->isCast()) {
+ Users.insert(Users.end(), CE->use_begin(), CE->use_end());
+ EqPointers.push_back(CE);
+ }
}
-
- Users.pop_back();
}
}
// Next, process all free calls...
if (FreeFunc) {
std::vector<User*> Users(FreeFunc->use_begin(), FreeFunc->use_end());
+ std::vector<Value*> EqPointers; // Values equal to FreeFunc
while (!Users.empty()) {
- if (Instruction *I = dyn_cast<Instruction>(Users.back())) {
+ User *U = Users.back();
+ Users.pop_back();
+
+ if (Instruction *I = dyn_cast<Instruction>(U)) {
+ if (isa<InvokeInst>(I))
+ continue;
CallSite CS = CallSite::get(I);
- if (CS.getInstruction() && CS.getCalledFunction() == FreeFunc &&
- CS.arg_begin() != CS.arg_end()) {
-
+ if (CS.getInstruction() && !CS.arg_empty() &&
+ (CS.getCalledFunction() == FreeFunc ||
+ std::find(EqPointers.begin(), EqPointers.end(),
+ CS.getCalledValue()) != EqPointers.end())) {
+
// If no prototype was provided for free, we may need to cast the
// source pointer. This should be really uncommon, but it's necessary
- // just in case we are dealing with wierd code like this:
+ // just in case we are dealing with weird code like this:
// free((long)ptr);
//
Value *Source = *CS.arg_begin();
if (!isa<PointerType>(Source->getType()))
- Source = new CastInst(Source, PointerType::get(Type::SByteTy),
- "FreePtrCast", I);
+ Source = new IntToPtrInst(Source,
+ PointerType::getUnqual(Type::Int8Ty),
+ "FreePtrCast", I);
new FreeInst(Source, I);
// If the old instruction was an invoke, add an unconditional branch
new BranchInst(II->getNormalDest(), I);
// Delete the old call site
- I->getParent()->getInstList().erase(I);
+ if (I->getType() != Type::VoidTy)
+ I->replaceAllUsesWith(UndefValue::get(I->getType()));
+ I->eraseFromParent();
Changed = true;
++NumRaised;
}
+ } else if (GlobalValue *GV = dyn_cast<GlobalValue>(U)) {
+ Users.insert(Users.end(), GV->use_begin(), GV->use_end());
+ EqPointers.push_back(GV);
+ } else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(U)) {
+ if (CE->isCast()) {
+ Users.insert(Users.end(), CE->use_begin(), CE->use_end());
+ EqPointers.push_back(CE);
+ }
}
-
- Users.pop_back();
}
}
return Changed;
}
-
-} // End llvm namespace