LLVM 19.0.0git
Macros | Typedefs | Functions | Variables
BoundsChecking.cpp File Reference
#include "llvm/Transforms/Instrumentation/BoundsChecking.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/Twine.h"
#include "llvm/Analysis/MemoryBuiltins.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Analysis/TargetFolder.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/InstIterator.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/Value.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include <cstdint>
#include <utility>

Go to the source code of this file.


#define DEBUG_TYPE   "bounds-checking"


using BuilderTy = IRBuilder< TargetFolder >


 STATISTIC (ChecksAdded, "Bounds checks added")
 STATISTIC (ChecksSkipped, "Bounds checks skipped")
 STATISTIC (ChecksUnable, "Bounds checks unable to add")
static ValuegetBoundsCheckCond (Value *Ptr, Value *InstVal, const DataLayout &DL, TargetLibraryInfo &TLI, ObjectSizeOffsetEvaluator &ObjSizeEval, BuilderTy &IRB, ScalarEvolution &SE)
 Gets the conditions under which memory accessing instructions will overflow.
template<typename GetTrapBBT >
static void insertBoundsCheck (Value *Or, BuilderTy &IRB, GetTrapBBT GetTrapBB)
 Adds run-time bounds checks to memory accessing instructions.
static bool addBoundsChecking (Function &F, TargetLibraryInfo &TLI, ScalarEvolution &SE)


static cl::opt< boolSingleTrapBB ("bounds-checking-single-trap", cl::desc("Use one trap block per function"))
static cl::opt< boolDebugTrapBB ("bounds-checking-unique-traps", cl::desc("Always use one trap per check"))

Macro Definition Documentation


#define DEBUG_TYPE   "bounds-checking"

Definition at line 35 of file BoundsChecking.cpp.

Typedef Documentation

◆ BuilderTy

Definition at line 47 of file BoundsChecking.cpp.

Function Documentation

◆ addBoundsChecking()

static bool addBoundsChecking ( Function F,
TargetLibraryInfo TLI,
ScalarEvolution SE 

◆ getBoundsCheckCond()

static Value * getBoundsCheckCond ( Value Ptr,
Value InstVal,
const DataLayout DL,
TargetLibraryInfo TLI,
ObjectSizeOffsetEvaluator ObjSizeEval,
BuilderTy IRB,
ScalarEvolution SE 

Gets the conditions under which memory accessing instructions will overflow.

Ptr is the pointer that will be read/written, and InstVal is either the result from the load or the value being stored. It is used to determine the size of memory block that is touched.

Returns the condition under which the access will overflow.

Definition at line 56 of file BoundsChecking.cpp.

References llvm::SizeOffsetType< T, C >::bothKnown(), llvm::ObjectSizeOffsetEvaluator::compute(), llvm::IRBuilderBase::CreateICmpSLT(), llvm::IRBuilderBase::CreateICmpULT(), llvm::IRBuilderBase::CreateOr(), llvm::IRBuilderBase::CreateSub(), llvm::IRBuilderBase::CreateTypeSize(), llvm::dbgs(), DL, llvm::ConstantInt::getFalse(), llvm::ScalarEvolution::getSCEV(), llvm::Value::getType(), llvm::ScalarEvolution::getUnsignedRange(), llvm::ConstantInt::getValue(), LLVM_DEBUG, llvm::SizeOffsetType< T, C >::Offset, llvm::Offset, llvm::Or, Ptr, llvm::SizeOffsetType< T, C >::Size, Size, and llvm::APInt::slt().

Referenced by addBoundsChecking().

◆ insertBoundsCheck()

template<typename GetTrapBBT >
static void insertBoundsCheck ( Value Or,
BuilderTy IRB,
GetTrapBBT  GetTrapBB 

Adds run-time bounds checks to memory accessing instructions.

Or is the condition that should guard the trap.

GetTrapBB is a callable that returns the trap BB to use on failure.

Definition at line 114 of file BoundsChecking.cpp.

References llvm::CallingConv::C, llvm::BranchInst::Create(), llvm::Instruction::eraseFromParent(), llvm::IRBuilderBase::GetInsertPoint(), llvm::BasicBlock::getParent(), llvm::BasicBlock::getTerminator(), llvm::Or, and llvm::BasicBlock::splitBasicBlock().

Referenced by addBoundsChecking().

◆ STATISTIC() [1/3]

STATISTIC ( ChecksAdded  ,
"Bounds checks added"   

◆ STATISTIC() [2/3]

STATISTIC ( ChecksSkipped  ,
"Bounds checks skipped"   

◆ STATISTIC() [3/3]

STATISTIC ( ChecksUnable  ,
"Bounds checks unable to add"   

Variable Documentation

◆ DebugTrapBB

cl::opt< bool > DebugTrapBB("bounds-checking-unique-traps", cl::desc("Always use one trap per check")) ( "bounds-checking-unique-traps"  ,
cl::desc("Always use one trap per check")   

Referenced by addBoundsChecking().

◆ SingleTrapBB

cl::opt< bool > SingleTrapBB("bounds-checking-single-trap", cl::desc("Use one trap block per function")) ( "bounds-checking-single-trap"  ,
cl::desc("Use one trap block per function")   

Referenced by addBoundsChecking().