// and potentially with other Sanitizers.
//
// We create a Guard variable with the same linkage
-// as the function and inject this code into the entry block (CoverageLevel=1)
-// or all blocks (CoverageLevel>=2):
+// as the function and inject this code into the entry block (SCK_Function)
+// or all blocks (SCK_BB):
// if (Guard < 0) {
// __sanitizer_cov(&Guard);
// }
// The accesses to Guard are atomic. The rest of the logic is
// in __sanitizer_cov (it's fine to call it more than once).
//
-// With CoverageLevel>=3 we also split critical edges this effectively
+// With SCK_Edge we also split critical edges this effectively
// instrumenting all edges.
//
-// CoverageLevel>=4 add indirect call profiling implented as a function call.
-//
// This coverage implementation provides very limited data:
// it only tells if a given function (block) was ever executed. No counters.
// But for many use cases this is what we need and the added slowdown small.
#include "llvm/Transforms/Instrumentation.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/SmallVector.h"
+#include "llvm/Analysis/LibCallSemantics.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/InlineAsm.h"
static const char *const kSanCovTraceEnter = "__sanitizer_cov_trace_func_enter";
static const char *const kSanCovTraceBB = "__sanitizer_cov_trace_basic_block";
static const char *const kSanCovTraceCmp = "__sanitizer_cov_trace_cmp";
+static const char *const kSanCovTraceSwitch = "__sanitizer_cov_trace_switch";
static const char *const kSanCovModuleCtorName = "sancov.module_ctor";
static const uint64_t kSanCtorAndDtorPriority = 2;
namespace {
+SanitizerCoverageOptions getOptions(int LegacyCoverageLevel) {
+ SanitizerCoverageOptions Res;
+ switch (LegacyCoverageLevel) {
+ case 0:
+ Res.CoverageType = SanitizerCoverageOptions::SCK_None;
+ break;
+ case 1:
+ Res.CoverageType = SanitizerCoverageOptions::SCK_Function;
+ break;
+ case 2:
+ Res.CoverageType = SanitizerCoverageOptions::SCK_BB;
+ break;
+ case 3:
+ Res.CoverageType = SanitizerCoverageOptions::SCK_Edge;
+ break;
+ case 4:
+ Res.CoverageType = SanitizerCoverageOptions::SCK_Edge;
+ Res.IndirectCalls = true;
+ break;
+ }
+ return Res;
+}
+
+SanitizerCoverageOptions OverrideFromCL(SanitizerCoverageOptions Options) {
+ // Sets CoverageType and IndirectCalls.
+ SanitizerCoverageOptions CLOpts = getOptions(ClCoverageLevel);
+ Options.CoverageType = std::max(Options.CoverageType, CLOpts.CoverageType);
+ Options.IndirectCalls |= CLOpts.IndirectCalls;
+ Options.TraceBB |= ClExperimentalTracing;
+ Options.TraceCmp |= ClExperimentalCMPTracing;
+ Options.Use8bitCounters |= ClUse8bitCounters;
+ return Options;
+}
+
class SanitizerCoverageModule : public ModulePass {
public:
- SanitizerCoverageModule(int CoverageLevel = 0)
- : ModulePass(ID),
- CoverageLevel(std::max(CoverageLevel, (int)ClCoverageLevel)) {}
+ SanitizerCoverageModule(
+ const SanitizerCoverageOptions &Options = SanitizerCoverageOptions())
+ : ModulePass(ID), Options(OverrideFromCL(Options)) {}
bool runOnModule(Module &M) override;
bool runOnFunction(Function &F);
static char ID; // Pass identification, replacement for typeid
void InjectCoverageForIndirectCalls(Function &F,
ArrayRef<Instruction *> IndirCalls);
void InjectTraceForCmp(Function &F, ArrayRef<Instruction *> CmpTraceTargets);
+ void InjectTraceForSwitch(Function &F,
+ ArrayRef<Instruction *> SwitchTraceTargets);
bool InjectCoverage(Function &F, ArrayRef<BasicBlock *> AllBlocks);
- void SetNoSanitizeMetada(Instruction *I);
+ void SetNoSanitizeMetadata(Instruction *I);
void InjectCoverageAtBlock(Function &F, BasicBlock &BB, bool UseCalls);
unsigned NumberOfInstrumentedBlocks() {
return SanCovFunction->getNumUses() + SanCovWithCheckFunction->getNumUses();
Function *SanCovFunction;
Function *SanCovWithCheckFunction;
Function *SanCovIndirCallFunction;
- Function *SanCovModuleInit;
Function *SanCovTraceEnter, *SanCovTraceBB;
Function *SanCovTraceCmpFunction;
+ Function *SanCovTraceSwitchFunction;
InlineAsm *EmptyAsm;
- Type *IntptrTy, *Int64Ty;
+ Type *IntptrTy, *Int64Ty, *Int64PtrTy;
+ Module *CurModule;
LLVMContext *C;
const DataLayout *DL;
GlobalVariable *GuardArray;
GlobalVariable *EightBitCounterArray;
- int CoverageLevel;
+ SanitizerCoverageOptions Options;
};
} // namespace
bool SanitizerCoverageModule::runOnModule(Module &M) {
- if (!CoverageLevel) return false;
+ if (Options.CoverageType == SanitizerCoverageOptions::SCK_None)
+ return false;
C = &(M.getContext());
DL = &M.getDataLayout();
+ CurModule = &M;
IntptrTy = Type::getIntNTy(*C, DL->getPointerSizeInBits());
Type *VoidTy = Type::getVoidTy(*C);
IRBuilder<> IRB(*C);
Type *Int8PtrTy = PointerType::getUnqual(IRB.getInt8Ty());
Type *Int32PtrTy = PointerType::getUnqual(IRB.getInt32Ty());
+ Int64PtrTy = PointerType::getUnqual(IRB.getInt64Ty());
Int64Ty = IRB.getInt64Ty();
- Function *CtorFunc =
- Function::Create(FunctionType::get(VoidTy, false),
- GlobalValue::InternalLinkage, kSanCovModuleCtorName, &M);
- ReturnInst::Create(*C, BasicBlock::Create(*C, "", CtorFunc));
- appendToGlobalCtors(M, CtorFunc, kSanCtorAndDtorPriority);
-
SanCovFunction = checkSanitizerInterfaceFunction(
M.getOrInsertFunction(kSanCovName, VoidTy, Int32PtrTy, nullptr));
SanCovWithCheckFunction = checkSanitizerInterfaceFunction(
SanCovTraceCmpFunction =
checkSanitizerInterfaceFunction(M.getOrInsertFunction(
kSanCovTraceCmp, VoidTy, Int64Ty, Int64Ty, Int64Ty, nullptr));
+ SanCovTraceSwitchFunction =
+ checkSanitizerInterfaceFunction(M.getOrInsertFunction(
+ kSanCovTraceSwitch, VoidTy, Int64Ty, Int64PtrTy, nullptr));
- SanCovModuleInit = checkSanitizerInterfaceFunction(M.getOrInsertFunction(
- kSanCovModuleInitName, Type::getVoidTy(*C), Int32PtrTy, IntptrTy,
- Int8PtrTy, Int8PtrTy, nullptr));
- SanCovModuleInit->setLinkage(Function::ExternalLinkage);
// We insert an empty inline asm after cov callbacks to avoid callback merge.
EmptyAsm = InlineAsm::get(FunctionType::get(IRB.getVoidTy(), false),
StringRef(""), StringRef(""),
/*hasSideEffects=*/true);
- if (ClExperimentalTracing) {
+ if (Options.TraceBB) {
SanCovTraceEnter = checkSanitizerInterfaceFunction(
M.getOrInsertFunction(kSanCovTraceEnter, VoidTy, Int32PtrTy, nullptr));
SanCovTraceBB = checkSanitizerInterfaceFunction(
GuardArray =
new GlobalVariable(M, Int32Ty, false, GlobalValue::ExternalLinkage,
nullptr, "__sancov_gen_cov_tmp");
- if (ClUse8bitCounters)
+ if (Options.Use8bitCounters)
EightBitCounterArray =
new GlobalVariable(M, Int8Ty, false, GlobalVariable::ExternalLinkage,
nullptr, "__sancov_gen_cov_tmp");
GuardArray->eraseFromParent();
GlobalVariable *RealEightBitCounterArray;
- if (ClUse8bitCounters) {
+ if (Options.Use8bitCounters) {
// Make sure the array is 16-aligned.
static const int kCounterAlignment = 16;
Type *Int8ArrayNTy =
new GlobalVariable(M, ModNameStrConst->getType(), true,
GlobalValue::PrivateLinkage, ModNameStrConst);
- // Call __sanitizer_cov_module_init
- IRB.SetInsertPoint(CtorFunc->getEntryBlock().getTerminator());
- IRB.CreateCall4(
- SanCovModuleInit, IRB.CreatePointerCast(RealGuardArray, Int32PtrTy),
- ConstantInt::get(IntptrTy, N),
- ClUse8bitCounters
- ? IRB.CreatePointerCast(RealEightBitCounterArray, Int8PtrTy)
- : Constant::getNullValue(Int8PtrTy),
- IRB.CreatePointerCast(ModuleName, Int8PtrTy));
+ Function *CtorFunc;
+ std::tie(CtorFunc, std::ignore) = createSanitizerCtorAndInitFunctions(
+ M, kSanCovModuleCtorName, kSanCovModuleInitName,
+ {Int32PtrTy, IntptrTy, Int8PtrTy, Int8PtrTy},
+ {IRB.CreatePointerCast(RealGuardArray, Int32PtrTy),
+ ConstantInt::get(IntptrTy, N),
+ Options.Use8bitCounters
+ ? IRB.CreatePointerCast(RealEightBitCounterArray, Int8PtrTy)
+ : Constant::getNullValue(Int8PtrTy),
+ IRB.CreatePointerCast(ModuleName, Int8PtrTy)});
+
+ appendToGlobalCtors(M, CtorFunc, kSanCtorAndDtorPriority);
+
return true;
}
if (F.empty()) return false;
if (F.getName().find(".module_ctor") != std::string::npos)
return false; // Should not instrument sanitizer init functions.
- if (CoverageLevel >= 3)
+ // Don't instrument functions using SEH for now. Splitting basic blocks like
+ // we do for coverage breaks WinEHPrepare.
+ // FIXME: Remove this when SEH no longer uses landingpad pattern matching.
+ if (F.hasPersonalityFn() &&
+ isAsynchronousEHPersonality(classifyEHPersonality(F.getPersonalityFn())))
+ return false;
+ if (Options.CoverageType >= SanitizerCoverageOptions::SCK_Edge)
SplitAllCriticalEdges(F);
SmallVector<Instruction*, 8> IndirCalls;
SmallVector<BasicBlock*, 16> AllBlocks;
SmallVector<Instruction*, 8> CmpTraceTargets;
+ SmallVector<Instruction*, 8> SwitchTraceTargets;
for (auto &BB : F) {
AllBlocks.push_back(&BB);
for (auto &Inst : BB) {
- if (CoverageLevel >= 4) {
+ if (Options.IndirectCalls) {
CallSite CS(&Inst);
if (CS && !CS.getCalledFunction())
IndirCalls.push_back(&Inst);
}
- if (ClExperimentalCMPTracing)
+ if (Options.TraceCmp) {
if (isa<ICmpInst>(&Inst))
CmpTraceTargets.push_back(&Inst);
+ if (isa<SwitchInst>(&Inst))
+ SwitchTraceTargets.push_back(&Inst);
+ }
}
}
InjectCoverage(F, AllBlocks);
InjectCoverageForIndirectCalls(F, IndirCalls);
InjectTraceForCmp(F, CmpTraceTargets);
+ InjectTraceForSwitch(F, SwitchTraceTargets);
return true;
}
bool SanitizerCoverageModule::InjectCoverage(Function &F,
ArrayRef<BasicBlock *> AllBlocks) {
- if (!CoverageLevel) return false;
-
- if (CoverageLevel == 1) {
+ switch (Options.CoverageType) {
+ case SanitizerCoverageOptions::SCK_None:
+ return false;
+ case SanitizerCoverageOptions::SCK_Function:
InjectCoverageAtBlock(F, F.getEntryBlock(), false);
- } else {
+ return true;
+ default: {
+ bool UseCalls = ClCoverageBlockThreshold < AllBlocks.size();
for (auto BB : AllBlocks)
- InjectCoverageAtBlock(F, *BB,
- ClCoverageBlockThreshold < AllBlocks.size());
+ InjectCoverageAtBlock(F, *BB, UseCalls);
+ return true;
+ }
}
- return true;
}
// On every indirect call we call a run-time function
*F.getParent(), Ty, false, GlobalValue::PrivateLinkage,
Constant::getNullValue(Ty), "__sancov_gen_callee_cache");
CalleeCache->setAlignment(kCacheAlignment);
- IRB.CreateCall2(SanCovIndirCallFunction,
- IRB.CreatePointerCast(Callee, IntptrTy),
- IRB.CreatePointerCast(CalleeCache, IntptrTy));
+ IRB.CreateCall(SanCovIndirCallFunction,
+ {IRB.CreatePointerCast(Callee, IntptrTy),
+ IRB.CreatePointerCast(CalleeCache, IntptrTy)});
}
}
+// For every switch statement we insert a call:
+// __sanitizer_cov_trace_switch(CondValue,
+// {NumCases, ValueSizeInBits, Case0Value, Case1Value, Case2Value, ... })
+
+void SanitizerCoverageModule::InjectTraceForSwitch(
+ Function &F, ArrayRef<Instruction *> SwitchTraceTargets) {
+ for (auto I : SwitchTraceTargets) {
+ if (SwitchInst *SI = dyn_cast<SwitchInst>(I)) {
+ IRBuilder<> IRB(I);
+ SmallVector<Constant *, 16> Initializers;
+ Value *Cond = SI->getCondition();
+ if (Cond->getType()->getScalarSizeInBits() >
+ Int64Ty->getScalarSizeInBits())
+ continue;
+ Initializers.push_back(ConstantInt::get(Int64Ty, SI->getNumCases()));
+ Initializers.push_back(
+ ConstantInt::get(Int64Ty, Cond->getType()->getScalarSizeInBits()));
+ if (Cond->getType()->getScalarSizeInBits() <
+ Int64Ty->getScalarSizeInBits())
+ Cond = IRB.CreateIntCast(Cond, Int64Ty, false);
+ for (auto It: SI->cases()) {
+ Constant *C = It.getCaseValue();
+ if (C->getType()->getScalarSizeInBits() <
+ Int64Ty->getScalarSizeInBits())
+ C = ConstantExpr::getCast(CastInst::ZExt, It.getCaseValue(), Int64Ty);
+ Initializers.push_back(C);
+ }
+ ArrayType *ArrayOfInt64Ty = ArrayType::get(Int64Ty, Initializers.size());
+ GlobalVariable *GV = new GlobalVariable(
+ *CurModule, ArrayOfInt64Ty, false, GlobalVariable::InternalLinkage,
+ ConstantArray::get(ArrayOfInt64Ty, Initializers),
+ "__sancov_gen_cov_switch_values");
+ IRB.CreateCall(SanCovTraceSwitchFunction,
+ {Cond, IRB.CreatePointerCast(GV, Int64PtrTy)});
+ }
+ }
+}
+
+
void SanitizerCoverageModule::InjectTraceForCmp(
Function &F, ArrayRef<Instruction *> CmpTraceTargets) {
- if (!ClExperimentalCMPTracing) return;
for (auto I : CmpTraceTargets) {
if (ICmpInst *ICMP = dyn_cast<ICmpInst>(I)) {
IRBuilder<> IRB(ICMP);
Value *A1 = ICMP->getOperand(1);
if (!A0->getType()->isIntegerTy()) continue;
uint64_t TypeSize = DL->getTypeStoreSizeInBits(A0->getType());
- // __sanitizer_cov_indir_call((type_size << 32) | predicate, A0, A1);
- IRB.CreateCall3(
+ // __sanitizer_cov_trace_cmp((type_size << 32) | predicate, A0, A1);
+ IRB.CreateCall(
SanCovTraceCmpFunction,
- ConstantInt::get(Int64Ty, (TypeSize << 32) | ICMP->getPredicate()),
- IRB.CreateIntCast(A0, Int64Ty, true),
- IRB.CreateIntCast(A1, Int64Ty, true));
+ {ConstantInt::get(Int64Ty, (TypeSize << 32) | ICMP->getPredicate()),
+ IRB.CreateIntCast(A0, Int64Ty, true),
+ IRB.CreateIntCast(A1, Int64Ty, true)});
}
}
}
-void SanitizerCoverageModule::SetNoSanitizeMetada(Instruction *I) {
+void SanitizerCoverageModule::SetNoSanitizeMetadata(Instruction *I) {
I->setMetadata(
I->getParent()->getParent()->getParent()->getMDKindID("nosanitize"),
MDNode::get(*C, None));
void SanitizerCoverageModule::InjectCoverageAtBlock(Function &F, BasicBlock &BB,
bool UseCalls) {
- BasicBlock::iterator IP = BB.getFirstInsertionPt(), BE = BB.end();
- // Skip static allocas at the top of the entry block so they don't become
- // dynamic when we split the block. If we used our optimized stack layout,
- // then there will only be one alloca and it will come first.
- for (; IP != BE; ++IP) {
- AllocaInst *AI = dyn_cast<AllocaInst>(IP);
- if (!AI || !AI->isStaticAlloca())
- break;
- }
+ // Don't insert coverage for unreachable blocks: we will never call
+ // __sanitizer_cov() for them, so counting them in
+ // NumberOfInstrumentedBlocks() might complicate calculation of code coverage
+ // percentage. Also, unreachable instructions frequently have no debug
+ // locations.
+ if (isa<UnreachableInst>(BB.getTerminator()))
+ return;
+ BasicBlock::iterator IP = BB.getFirstInsertionPt();
bool IsEntryBB = &BB == &F.getEntryBlock();
- DebugLoc EntryLoc = IsEntryBB && IP->getDebugLoc()
- ? IP->getDebugLoc().getFnDebugLoc()
- : IP->getDebugLoc();
+ DebugLoc EntryLoc;
+ if (IsEntryBB) {
+ if (auto SP = getDISubprogram(&F))
+ EntryLoc = DebugLoc::get(SP->getScopeLine(), 0, SP);
+ // Keep static allocas and llvm.localescape calls in the entry block. Even
+ // if we aren't splitting the block, it's nice for allocas to be before
+ // calls.
+ IP = PrepareToSplitEntryBlock(BB, IP);
+ } else {
+ EntryLoc = IP->getDebugLoc();
+ }
+
IRBuilder<> IRB(IP);
IRB.SetCurrentDebugLocation(EntryLoc);
- SmallVector<Value *, 1> Indices;
Value *GuardP = IRB.CreateAdd(
IRB.CreatePointerCast(GuardArray, IntptrTy),
ConstantInt::get(IntptrTy, (1 + NumberOfInstrumentedBlocks()) * 4));
LoadInst *Load = IRB.CreateLoad(GuardP);
Load->setAtomic(Monotonic);
Load->setAlignment(4);
- SetNoSanitizeMetada(Load);
+ SetNoSanitizeMetadata(Load);
Value *Cmp = IRB.CreateICmpSGE(Constant::getNullValue(Load->getType()), Load);
Instruction *Ins = SplitBlockAndInsertIfThen(
Cmp, IP, false, MDBuilder(*C).createBranchWeights(1, 100000));
IRB.SetCurrentDebugLocation(EntryLoc);
// __sanitizer_cov gets the PC of the instruction using GET_CALLER_PC.
IRB.CreateCall(SanCovFunction, GuardP);
- IRB.CreateCall(EmptyAsm); // Avoids callback merge.
+ IRB.CreateCall(EmptyAsm, {}); // Avoids callback merge.
}
- if(ClUse8bitCounters) {
+ if (Options.Use8bitCounters) {
IRB.SetInsertPoint(IP);
Value *P = IRB.CreateAdd(
IRB.CreatePointerCast(EightBitCounterArray, IntptrTy),
LoadInst *LI = IRB.CreateLoad(P);
Value *Inc = IRB.CreateAdd(LI, ConstantInt::get(IRB.getInt8Ty(), 1));
StoreInst *SI = IRB.CreateStore(Inc, P);
- SetNoSanitizeMetada(LI);
- SetNoSanitizeMetada(SI);
+ SetNoSanitizeMetadata(LI);
+ SetNoSanitizeMetadata(SI);
}
- if (ClExperimentalTracing) {
+ if (Options.TraceBB) {
// Experimental support for tracing.
// Insert a callback with the same guard variable as used for coverage.
IRB.SetInsertPoint(IP);
INITIALIZE_PASS(SanitizerCoverageModule, "sancov",
"SanitizerCoverage: TODO."
"ModulePass", false, false)
-ModulePass *llvm::createSanitizerCoverageModulePass(int CoverageLevel) {
- return new SanitizerCoverageModule(CoverageLevel);
+ModulePass *llvm::createSanitizerCoverageModulePass(
+ const SanitizerCoverageOptions &Options) {
+ return new SanitizerCoverageModule(Options);
}
projects / oota-llvm.git / blobdiff