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//===-- IntrinsicCleaner.cpp ----------------------------------------------===//
//
// The KLEE Symbolic Virtual Machine
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "Passes.h"
#include "klee/Config/Version.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Function.h"
#include "llvm/InstrTypes.h"
#include "llvm/Instruction.h"
#include "llvm/Instructions.h"
#include "llvm/IntrinsicInst.h"
#if LLVM_VERSION_CODE >= LLVM_VERSION(2, 7)
#include "llvm/LLVMContext.h"
#endif
#include "llvm/Module.h"
#include "llvm/Pass.h"
#include "llvm/Type.h"
#if LLVM_VERSION_CODE >= LLVM_VERSION(3, 2)
#include "llvm/IRBuilder.h"
#else
#include "llvm/Support/IRBuilder.h"
#endif
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#if LLVM_VERSION_CODE <= LLVM_VERSION(3, 1)
#include "llvm/Target/TargetData.h"
#else
#include "llvm/DataLayout.h"
#endif
using namespace llvm;
namespace klee {
char IntrinsicCleanerPass::ID;
bool IntrinsicCleanerPass::runOnModule(Module &M) {
bool dirty = false;
for (Module::iterator f = M.begin(), fe = M.end(); f != fe; ++f)
for (Function::iterator b = f->begin(), be = f->end(); b != be; ++b)
dirty |= runOnBasicBlock(*b);
return dirty;
}
bool IntrinsicCleanerPass::runOnBasicBlock(BasicBlock &b) {
bool dirty = false;
#if LLVM_VERSION_CODE <= LLVM_VERSION(3, 1)
unsigned WordSize = TargetData.getPointerSizeInBits() / 8;
#else
unsigned WordSize = DataLayout.getPointerSizeInBits() / 8;
#endif
for (BasicBlock::iterator i = b.begin(), ie = b.end(); i != ie;) {
IntrinsicInst *ii = dyn_cast<IntrinsicInst>(&*i);
// increment now since LowerIntrinsic deletion makes iterator invalid.
++i;
if(ii) {
switch (ii->getIntrinsicID()) {
case Intrinsic::vastart:
case Intrinsic::vaend:
break;
// Lower vacopy so that object resolution etc is handled by
// normal instructions.
//
// FIXME: This is much more target dependent than just the word size,
// however this works for x86-32 and x86-64.
case Intrinsic::vacopy: { // (dst, src) -> *((i8**) dst) = *((i8**) src)
#if LLVM_VERSION_CODE < LLVM_VERSION(2, 8)
Value *dst = ii->getOperand(1);
Value *src = ii->getOperand(2);
#else
Value *dst = ii->getArgOperand(0);
Value *src = ii->getArgOperand(1);
#endif
if (WordSize == 4) {
Type *i8pp = PointerType::getUnqual(PointerType::getUnqual(Type::getInt8Ty(getGlobalContext())));
Value *castedDst = CastInst::CreatePointerCast(dst, i8pp, "vacopy.cast.dst", ii);
Value *castedSrc = CastInst::CreatePointerCast(src, i8pp, "vacopy.cast.src", ii);
Value *load = new LoadInst(castedSrc, "vacopy.read", ii);
new StoreInst(load, castedDst, false, ii);
} else {
assert(WordSize == 8 && "Invalid word size!");
Type *i64p = PointerType::getUnqual(Type::getInt64Ty(getGlobalContext()));
Value *pDst = CastInst::CreatePointerCast(dst, i64p, "vacopy.cast.dst", ii);
Value *pSrc = CastInst::CreatePointerCast(src, i64p, "vacopy.cast.src", ii);
Value *val = new LoadInst(pSrc, std::string(), ii); new StoreInst(val, pDst, ii);
Value *off = ConstantInt::get(Type::getInt64Ty(getGlobalContext()), 1);
pDst = GetElementPtrInst::Create(pDst, off, std::string(), ii);
pSrc = GetElementPtrInst::Create(pSrc, off, std::string(), ii);
val = new LoadInst(pSrc, std::string(), ii); new StoreInst(val, pDst, ii);
pDst = GetElementPtrInst::Create(pDst, off, std::string(), ii);
pSrc = GetElementPtrInst::Create(pSrc, off, std::string(), ii);
val = new LoadInst(pSrc, std::string(), ii); new StoreInst(val, pDst, ii);
}
ii->removeFromParent();
delete ii;
break;
}
case Intrinsic::uadd_with_overflow:
case Intrinsic::umul_with_overflow: {
IRBuilder<> builder(ii->getParent(), ii);
#if LLVM_VERSION_CODE < LLVM_VERSION(2, 8)
Value *op1 = ii->getOperand(1);
Value *op2 = ii->getOperand(2);
#else
Value *op1 = ii->getArgOperand(0);
Value *op2 = ii->getArgOperand(1);
#endif
Value *result = 0;
if (ii->getIntrinsicID() == Intrinsic::uadd_with_overflow)
result = builder.CreateAdd(op1, op2);
else
result = builder.CreateMul(op1, op2);
Value *overflow = builder.CreateICmpULT(result, op1);
Value *resultStruct =
builder.CreateInsertValue(UndefValue::get(ii->getType()), result, 0);
resultStruct = builder.CreateInsertValue(resultStruct, overflow, 1);
ii->replaceAllUsesWith(resultStruct);
ii->removeFromParent();
delete ii;
dirty = true;
break;
}
#if LLVM_VERSION_CODE < LLVM_VERSION(2, 7)
case Intrinsic::dbg_stoppoint: {
// We can remove this stoppoint if the next instruction is
// sure to be another stoppoint. This is nice for cleanliness
// but also important for switch statements where it can allow
// the targets to be joined.
bool erase = false;
if (isa<DbgStopPointInst>(i) ||
isa<UnreachableInst>(i)) {
erase = true;
} else if (isa<BranchInst>(i) ||
isa<SwitchInst>(i)) {
BasicBlock *bb = i->getParent();
erase = true;
for (succ_iterator it=succ_begin(bb), ie=succ_end(bb);
it!=ie; ++it) {
if (!isa<DbgStopPointInst>(it->getFirstNonPHI())) {
erase = false;
break;
}
}
}
if (erase) {
ii->eraseFromParent();
dirty = true;
}
break;
}
case Intrinsic::dbg_region_start:
case Intrinsic::dbg_region_end:
case Intrinsic::dbg_func_start:
#else
case Intrinsic::dbg_value:
#endif
case Intrinsic::dbg_declare:
// Remove these regardless of lower intrinsics flag. This can
// be removed once IntrinsicLowering is fixed to not have bad
// caches.
ii->eraseFromParent();
dirty = true;
break;
default:
if (LowerIntrinsics)
IL->LowerIntrinsicCall(ii);
dirty = true;
break;
}
}
}
return dirty;
}
}
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