[llvm-commits] [llvm] r168866 - in /llvm/trunk: include/llvm/InitializePasses.h include/llvm/Transforms/Instrumentation.h lib/Transforms/Instrumentation/CMakeLists.txt lib/Transforms/Instrumentation/Instrumentation.cpp lib/Transforms/Instrumentation/MemorySanitizer.cpp test/Instrumentation/MemorySanitizer/ test/Instrumentation/MemorySanitizer/lit.local.cfg test/Instrumentation/MemorySanitizer/msan_basic.ll
Evgeniy Stepanov
eugeni.stepanov at gmail.com
Thu Nov 29 01:57:20 PST 2012
Author: eugenis
Date: Thu Nov 29 03:57:20 2012
New Revision: 168866
URL: http://llvm.org/viewvc/llvm-project?rev=168866&view=rev
Log:
Initial commit of MemorySanitizer.
Compiler pass only.
Added:
llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp (with props)
llvm/trunk/test/Instrumentation/MemorySanitizer/
llvm/trunk/test/Instrumentation/MemorySanitizer/lit.local.cfg
llvm/trunk/test/Instrumentation/MemorySanitizer/msan_basic.ll
Modified:
llvm/trunk/include/llvm/InitializePasses.h
llvm/trunk/include/llvm/Transforms/Instrumentation.h
llvm/trunk/lib/Transforms/Instrumentation/CMakeLists.txt
llvm/trunk/lib/Transforms/Instrumentation/Instrumentation.cpp
Modified: llvm/trunk/include/llvm/InitializePasses.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/InitializePasses.h?rev=168866&r1=168865&r2=168866&view=diff
==============================================================================
--- llvm/trunk/include/llvm/InitializePasses.h (original)
+++ llvm/trunk/include/llvm/InitializePasses.h Thu Nov 29 03:57:20 2012
@@ -111,6 +111,7 @@
void initializeGCOVProfilerPass(PassRegistry&);
void initializeAddressSanitizerPass(PassRegistry&);
void initializeAddressSanitizerModulePass(PassRegistry&);
+void initializeMemorySanitizerPass(PassRegistry&);
void initializeThreadSanitizerPass(PassRegistry&);
void initializeEarlyCSEPass(PassRegistry&);
void initializeExpandISelPseudosPass(PassRegistry&);
Modified: llvm/trunk/include/llvm/Transforms/Instrumentation.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Transforms/Instrumentation.h?rev=168866&r1=168865&r2=168866&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Transforms/Instrumentation.h (original)
+++ llvm/trunk/include/llvm/Transforms/Instrumentation.h Thu Nov 29 03:57:20 2012
@@ -36,6 +36,8 @@
// Insert AddressSanitizer (address sanity checking) instrumentation
FunctionPass *createAddressSanitizerFunctionPass();
ModulePass *createAddressSanitizerModulePass();
+// Insert MemorySanitizer instrumentation (detection of uninitialized reads)
+FunctionPass *createMemorySanitizerPass();
// Insert ThreadSanitizer (race detection) instrumentation
FunctionPass *createThreadSanitizerPass();
Modified: llvm/trunk/lib/Transforms/Instrumentation/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Instrumentation/CMakeLists.txt?rev=168866&r1=168865&r2=168866&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Instrumentation/CMakeLists.txt (original)
+++ llvm/trunk/lib/Transforms/Instrumentation/CMakeLists.txt Thu Nov 29 03:57:20 2012
@@ -4,6 +4,7 @@
BoundsChecking.cpp
EdgeProfiling.cpp
GCOVProfiling.cpp
+ MemorySanitizer.cpp
Instrumentation.cpp
OptimalEdgeProfiling.cpp
PathProfiling.cpp
Modified: llvm/trunk/lib/Transforms/Instrumentation/Instrumentation.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Instrumentation/Instrumentation.cpp?rev=168866&r1=168865&r2=168866&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Instrumentation/Instrumentation.cpp (original)
+++ llvm/trunk/lib/Transforms/Instrumentation/Instrumentation.cpp Thu Nov 29 03:57:20 2012
@@ -27,6 +27,7 @@
initializeGCOVProfilerPass(Registry);
initializeOptimalEdgeProfilerPass(Registry);
initializePathProfilerPass(Registry);
+ initializeMemorySanitizerPass(Registry);
initializeThreadSanitizerPass(Registry);
}
Added: llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp?rev=168866&view=auto
==============================================================================
--- llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp (added)
+++ llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp Thu Nov 29 03:57:20 2012
@@ -0,0 +1,1419 @@
+//===-- MemorySanitizer.cpp - detector of uninitialized reads -------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+/// \file
+/// This file is a part of MemorySanitizer, a detector of uninitialized
+/// reads.
+///
+/// Status: early prototype.
+///
+/// The algorithm of the tool is similar to Memcheck
+/// (http://goo.gl/QKbem). We associate a few shadow bits with every
+/// byte of the application memory, poison the shadow of the malloc-ed
+/// or alloca-ed memory, load the shadow bits on every memory read,
+/// propagate the shadow bits through some of the arithmetic
+/// instruction (including MOV), store the shadow bits on every memory
+/// write, report a bug on some other instructions (e.g. JMP) if the
+/// associated shadow is poisoned.
+///
+/// But there are differences too. The first and the major one:
+/// compiler instrumentation instead of binary instrumentation. This
+/// gives us much better register allocation, possible compiler
+/// optimizations and a fast start-up. But this brings the major issue
+/// as well: msan needs to see all program events, including system
+/// calls and reads/writes in system libraries, so we either need to
+/// compile *everything* with msan or use a binary translation
+/// component (e.g. DynamoRIO) to instrument pre-built libraries.
+/// Another difference from Memcheck is that we use 8 shadow bits per
+/// byte of application memory and use a direct shadow mapping. This
+/// greatly simplifies the instrumentation code and avoids races on
+/// shadow updates (Memcheck is single-threaded so races are not a
+/// concern there. Memcheck uses 2 shadow bits per byte with a slow
+/// path storage that uses 8 bits per byte).
+///
+/// The default value of shadow is 0, which means "clean" (not poisoned).
+///
+/// Every module initializer should call __msan_init to ensure that the
+/// shadow memory is ready. On error, __msan_warning is called. Since
+/// parameters and return values may be passed via registers, we have a
+/// specialized thread-local shadow for return values
+/// (__msan_retval_tls) and parameters (__msan_param_tls).
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "msan"
+
+#include "BlackList.h"
+#include "llvm/DataLayout.h"
+#include "llvm/Function.h"
+#include "llvm/InlineAsm.h"
+#include "llvm/IntrinsicInst.h"
+#include "llvm/IRBuilder.h"
+#include "llvm/LLVMContext.h"
+#include "llvm/MDBuilder.h"
+#include "llvm/Module.h"
+#include "llvm/Type.h"
+#include "llvm/ADT/DepthFirstIterator.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/ValueMap.h"
+#include "llvm/Transforms/Instrumentation.h"
+#include "llvm/Transforms/Utils/BasicBlockUtils.h"
+#include "llvm/Transforms/Utils/ModuleUtils.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Compiler.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/InstVisitor.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Transforms/Instrumentation.h"
+#include "llvm/Transforms/Utils/BasicBlockUtils.h"
+#include "llvm/Transforms/Utils/ModuleUtils.h"
+
+using namespace llvm;
+
+static const uint64_t kShadowMask32 = 1ULL << 31;
+static const uint64_t kShadowMask64 = 1ULL << 46;
+static const uint64_t kOriginOffset32 = 1ULL << 30;
+static const uint64_t kOriginOffset64 = 1ULL << 45;
+
+// This is an important flag that makes the reports much more
+// informative at the cost of greater slowdown. Not fully implemented
+// yet.
+// FIXME: this should be a top-level clang flag, e.g.
+// -fmemory-sanitizer-full.
+static cl::opt<bool> ClTrackOrigins("msan-track-origins",
+ cl::desc("Track origins (allocation sites) of poisoned memory"),
+ cl::Hidden, cl::init(false));
+static cl::opt<bool> ClKeepGoing("msan-keep-going",
+ cl::desc("keep going after reporting a UMR"),
+ cl::Hidden, cl::init(false));
+static cl::opt<bool> ClPoisonStack("msan-poison-stack",
+ cl::desc("poison uninitialized stack variables"),
+ cl::Hidden, cl::init(true));
+static cl::opt<bool> ClPoisonStackWithCall("msan-poison-stack-with-call",
+ cl::desc("poison uninitialized stack variables with a call"),
+ cl::Hidden, cl::init(false));
+static cl::opt<int> ClPoisonStackPattern("msan-poison-stack-pattern",
+ cl::desc("poison uninitialized stack variables with the given patter"),
+ cl::Hidden, cl::init(0xff));
+
+static cl::opt<bool> ClHandleICmp("msan-handle-icmp",
+ cl::desc("propagate shadow through ICmpEQ and ICmpNE"),
+ cl::Hidden, cl::init(true));
+
+// This flag controls whether we check the shadow of the address
+// operand of load or store. Such bugs are very rare, since load from
+// a garbage address typically results in SEGV, but still happen
+// (e.g. only lower bits of address are garbage, or the access happens
+// early at program startup where malloc-ed memory is more likely to
+// be zeroed. As of 2012-08-28 this flag adds 20% slowdown.
+static cl::opt<bool> ClCheckAccessAddress("msan-check-access-address",
+ cl::desc("report accesses through a pointer which has poisoned shadow"),
+ cl::Hidden, cl::init(true));
+
+static cl::opt<bool> ClDumpStrictInstructions("msan-dump-strict-instructions",
+ cl::desc("print out instructions with default strict semantics"),
+ cl::Hidden, cl::init(false));
+
+static cl::opt<std::string> ClBlackListFile("msan-blacklist",
+ cl::desc("File containing the list of functions where MemorySanitizer "
+ "should not report bugs"), cl::Hidden);
+
+namespace {
+
+/// \brief An instrumentation pass implementing detection of uninitialized
+/// reads.
+///
+/// MemorySanitizer: instrument the code in module to find
+/// uninitialized reads.
+class MemorySanitizer : public FunctionPass {
+public:
+ MemorySanitizer() : FunctionPass(ID), TD(0) { }
+ const char *getPassName() const { return "MemorySanitizer"; }
+ bool runOnFunction(Function &F);
+ bool doInitialization(Module &M);
+ static char ID; // Pass identification, replacement for typeid.
+
+private:
+ DataLayout *TD;
+ LLVMContext *C;
+ Type *IntptrTy;
+ Type *OriginTy;
+ /// \brief Thread-local shadow storage for function parameters.
+ GlobalVariable *ParamTLS;
+ /// \brief Thread-local origin storage for function parameters.
+ GlobalVariable *ParamOriginTLS;
+ /// \brief Thread-local shadow storage for function return value.
+ GlobalVariable *RetvalTLS;
+ /// \brief Thread-local origin storage for function return value.
+ GlobalVariable *RetvalOriginTLS;
+ /// \brief Thread-local shadow storage for in-register va_arg function
+ /// parameters (x86_64-specific).
+ GlobalVariable *VAArgTLS;
+ /// \brief Thread-local shadow storage for va_arg overflow area
+ /// (x86_64-specific).
+ GlobalVariable *VAArgOverflowSizeTLS;
+ /// \brief Thread-local space used to pass origin value to the UMR reporting
+ /// function.
+ GlobalVariable *OriginTLS;
+
+ /// \brief The run-time callback to print a warning.
+ Value *WarningFn;
+ /// \brief Run-time helper that copies origin info for a memory range.
+ Value *MsanCopyOriginFn;
+ /// \brief Run-time helper that generates a new origin value for a stack
+ /// allocation.
+ Value *MsanSetAllocaOriginFn;
+ /// \brief Run-time helper that poisons stack on function entry.
+ Value *MsanPoisonStackFn;
+ /// \brief The actual "memmove" function.
+ Value *MemmoveFn;
+
+ /// \brief Address mask used in application-to-shadow address calculation.
+ /// ShadowAddr is computed as ApplicationAddr & ~ShadowMask.
+ uint64_t ShadowMask;
+ /// \brief Offset of the origin shadow from the "normal" shadow.
+ /// OriginAddr is computed as (ShadowAddr + OriginOffset) & ~3ULL
+ uint64_t OriginOffset;
+ /// \brief Branch weights for error reporting.
+ MDNode *ColdCallWeights;
+ /// \brief The blacklist.
+ OwningPtr<BlackList> BL;
+
+ friend class MemorySanitizerVisitor;
+ friend class VarArgAMD64Helper;
+};
+} // namespace
+
+char MemorySanitizer::ID = 0;
+INITIALIZE_PASS(MemorySanitizer, "msan",
+ "MemorySanitizer: detects uninitialized reads.",
+ false, false)
+
+FunctionPass *llvm::createMemorySanitizerPass() {
+ return new MemorySanitizer();
+}
+
+/// \brief Create a non-const global initialized with the given string.
+///
+/// Creates a writable global for Str so that we can pass it to the
+/// run-time lib. Runtime uses first 4 bytes of the string to store the
+/// frame ID, so the string needs to be mutable.
+static GlobalVariable *createPrivateNonConstGlobalForString(Module &M,
+ StringRef Str) {
+ Constant *StrConst = ConstantDataArray::getString(M.getContext(), Str);
+ return new GlobalVariable(M, StrConst->getType(), /*isConstant=*/false,
+ GlobalValue::PrivateLinkage, StrConst, "");
+}
+
+/// \brief Module-level initialization.
+///
+/// Obtains pointers to the required runtime library functions, and
+/// inserts a call to __msan_init to the module's constructor list.
+bool MemorySanitizer::doInitialization(Module &M) {
+ TD = getAnalysisIfAvailable<DataLayout>();
+ if (!TD)
+ return false;
+ BL.reset(new BlackList(ClBlackListFile));
+ C = &(M.getContext());
+ unsigned PtrSize = TD->getPointerSizeInBits(/* AddressSpace */0);
+ switch (PtrSize) {
+ case 64:
+ ShadowMask = kShadowMask64;
+ OriginOffset = kOriginOffset64;
+ break;
+ case 32:
+ ShadowMask = kShadowMask32;
+ OriginOffset = kOriginOffset32;
+ break;
+ default:
+ report_fatal_error("unsupported pointer size");
+ break;
+ }
+
+ IRBuilder<> IRB(*C);
+ IntptrTy = IRB.getIntPtrTy(TD);
+ OriginTy = IRB.getInt32Ty();
+
+ ColdCallWeights = MDBuilder(*C).createBranchWeights(1, 1000);
+
+ // Insert a call to __msan_init/__msan_track_origins into the module's CTORs.
+ appendToGlobalCtors(M, cast<Function>(M.getOrInsertFunction(
+ "__msan_init", IRB.getVoidTy(), NULL)), 0);
+
+ new GlobalVariable(M, IRB.getInt32Ty(), true, GlobalValue::LinkOnceODRLinkage,
+ IRB.getInt32(ClTrackOrigins), "__msan_track_origins");
+
+ // Create the callback.
+ // FIXME: this function should have "Cold" calling conv,
+ // which is not yet implemented.
+ StringRef WarningFnName = ClKeepGoing ? "__msan_warning"
+ : "__msan_warning_noreturn";
+ WarningFn = M.getOrInsertFunction(WarningFnName, IRB.getVoidTy(), NULL);
+
+ MsanCopyOriginFn = M.getOrInsertFunction(
+ "__msan_copy_origin", IRB.getVoidTy(), IRB.getInt8PtrTy(),
+ IRB.getInt8PtrTy(), IntptrTy, NULL);
+ MsanSetAllocaOriginFn = M.getOrInsertFunction(
+ "__msan_set_alloca_origin", IRB.getVoidTy(), IRB.getInt8PtrTy(), IntptrTy,
+ IRB.getInt8PtrTy(), NULL);
+ MsanPoisonStackFn = M.getOrInsertFunction(
+ "__msan_poison_stack", IRB.getVoidTy(), IRB.getInt8PtrTy(), IntptrTy, NULL);
+ MemmoveFn = M.getOrInsertFunction(
+ "memmove", IRB.getInt8PtrTy(), IRB.getInt8PtrTy(), IRB.getInt8PtrTy(),
+ IntptrTy, NULL);
+
+ // Create globals.
+ RetvalTLS = new GlobalVariable(
+ M, ArrayType::get(IRB.getInt64Ty(), 8), false,
+ GlobalVariable::ExternalLinkage, 0, "__msan_retval_tls", 0,
+ GlobalVariable::GeneralDynamicTLSModel);
+ RetvalOriginTLS = new GlobalVariable(
+ M, OriginTy, false, GlobalVariable::ExternalLinkage, 0,
+ "__msan_retval_origin_tls", 0, GlobalVariable::GeneralDynamicTLSModel);
+
+ ParamTLS = new GlobalVariable(
+ M, ArrayType::get(IRB.getInt64Ty(), 1000), false,
+ GlobalVariable::ExternalLinkage, 0, "__msan_param_tls", 0,
+ GlobalVariable::GeneralDynamicTLSModel);
+ ParamOriginTLS = new GlobalVariable(
+ M, ArrayType::get(OriginTy, 1000), false, GlobalVariable::ExternalLinkage,
+ 0, "__msan_param_origin_tls", 0, GlobalVariable::GeneralDynamicTLSModel);
+
+ VAArgTLS = new GlobalVariable(
+ M, ArrayType::get(IRB.getInt64Ty(), 1000), false,
+ GlobalVariable::ExternalLinkage, 0, "__msan_va_arg_tls", 0,
+ GlobalVariable::GeneralDynamicTLSModel);
+ VAArgOverflowSizeTLS = new GlobalVariable(
+ M, IRB.getInt64Ty(), false, GlobalVariable::ExternalLinkage, 0,
+ "__msan_va_arg_overflow_size_tls", 0,
+ GlobalVariable::GeneralDynamicTLSModel);
+ OriginTLS = new GlobalVariable(
+ M, IRB.getInt32Ty(), false, GlobalVariable::ExternalLinkage, 0,
+ "__msan_origin_tls", 0, GlobalVariable::GeneralDynamicTLSModel);
+ return true;
+}
+
+namespace {
+
+/// \brief A helper class that handles instrumentation of VarArg
+/// functions on a particular platform.
+///
+/// Implementations are expected to insert the instrumentation
+/// necessary to propagate argument shadow through VarArg function
+/// calls. Visit* methods are called during an InstVisitor pass over
+/// the function, and should avoid creating new basic blocks. A new
+/// instance of this class is created for each instrumented function.
+struct VarArgHelper {
+ /// \brief Visit a CallSite.
+ virtual void visitCallSite(CallSite &CS, IRBuilder<> &IRB) = 0;
+
+ /// \brief Visit a va_start call.
+ virtual void visitVAStartInst(VAStartInst &I) = 0;
+
+ /// \brief Visit a va_copy call.
+ virtual void visitVACopyInst(VACopyInst &I) = 0;
+
+ /// \brief Finalize function instrumentation.
+ ///
+ /// This method is called after visiting all interesting (see above)
+ /// instructions in a function.
+ virtual void finalizeInstrumentation() = 0;
+};
+
+struct MemorySanitizerVisitor;
+
+VarArgHelper*
+CreateVarArgHelper(Function &Func, MemorySanitizer &Msan,
+ MemorySanitizerVisitor &Visitor);
+
+/// This class does all the work for a given function. Store and Load
+/// instructions store and load corresponding shadow and origin
+/// values. Most instructions propagate shadow from arguments to their
+/// return values. Certain instructions (most importantly, BranchInst)
+/// test their argument shadow and print reports (with a runtime call) if it's
+/// non-zero.
+struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
+ Function &F;
+ MemorySanitizer &MS;
+ SmallVector<PHINode *, 16> ShadowPHINodes, OriginPHINodes;
+ ValueMap<Value*, Value*> ShadowMap, OriginMap;
+ bool InsertChecks;
+ OwningPtr<VarArgHelper> VAHelper;
+
+ // An unfortunate workaround for asymmetric lowering of va_arg stuff.
+ // See a comment in visitCallSite for more details.
+ static const unsigned AMD64GpEndOffset = 48; // AMD64 ABI Draft 0.99.6 p3.5.7
+ static const unsigned AMD64FpEndOffset = 176;
+
+ struct ShadowOriginAndInsertPoint {
+ Instruction *Shadow;
+ Instruction *Origin;
+ Instruction *OrigIns;
+ ShadowOriginAndInsertPoint(Instruction *S, Instruction *O, Instruction *I)
+ : Shadow(S), Origin(O), OrigIns(I) { }
+ ShadowOriginAndInsertPoint() : Shadow(0), Origin(0), OrigIns(0) { }
+ };
+ SmallVector<ShadowOriginAndInsertPoint, 16> InstrumentationList;
+
+ MemorySanitizerVisitor(Function &F, MemorySanitizer &MS)
+ : F(F), MS(MS), VAHelper(CreateVarArgHelper(F, MS, *this)) {
+ InsertChecks = !MS.BL->isIn(F);
+ DEBUG(if (!InsertChecks)
+ dbgs() << "MemorySanitizer is not inserting checks into '"
+ << F.getName() << "'\n");
+ }
+
+ void materializeChecks() {
+ for (size_t i = 0, n = InstrumentationList.size(); i < n; i++) {
+ Instruction *Shadow = InstrumentationList[i].Shadow;
+ Instruction *OrigIns = InstrumentationList[i].OrigIns;
+ IRBuilder<> IRB(OrigIns);
+ DEBUG(dbgs() << " SHAD0 : " << *Shadow << "\n");
+ Value *ConvertedShadow = convertToShadowTyNoVec(Shadow, IRB);
+ DEBUG(dbgs() << " SHAD1 : " << *ConvertedShadow << "\n");
+ Value *Cmp = IRB.CreateICmpNE(ConvertedShadow,
+ getCleanShadow(ConvertedShadow), "_mscmp");
+ Instruction *CheckTerm =
+ SplitBlockAndInsertIfThen(cast<Instruction>(Cmp),
+ /* Unreachable */ !ClKeepGoing,
+ MS.ColdCallWeights);
+
+ IRB.SetInsertPoint(CheckTerm);
+ if (ClTrackOrigins) {
+ Instruction *Origin = InstrumentationList[i].Origin;
+ IRB.CreateStore(Origin ? (Value*)Origin : (Value*)IRB.getInt32(0),
+ MS.OriginTLS);
+ }
+ CallInst *Call = IRB.CreateCall(MS.WarningFn);
+ Call->setDebugLoc(OrigIns->getDebugLoc());
+ DEBUG(dbgs() << " CHECK: " << *Cmp << "\n");
+ }
+ DEBUG(dbgs() << "DONE:\n" << F);
+ }
+
+ /// \brief Add MemorySanitizer instrumentation to a function.
+ bool runOnFunction() {
+ if (!MS.TD) return false;
+ // Iterate all BBs in depth-first order and create shadow instructions
+ // for all instructions (where applicable).
+ // For PHI nodes we create dummy shadow PHIs which will be finalized later.
+ for (df_iterator<BasicBlock*> DI = df_begin(&F.getEntryBlock()),
+ DE = df_end(&F.getEntryBlock()); DI != DE; ++DI) {
+ BasicBlock *BB = *DI;
+ visit(*BB);
+ }
+
+ // Finalize PHI nodes.
+ for (size_t i = 0, n = ShadowPHINodes.size(); i < n; i++) {
+ PHINode *PN = ShadowPHINodes[i];
+ PHINode *PNS = cast<PHINode>(getShadow(PN));
+ PHINode *PNO = ClTrackOrigins ? cast<PHINode>(getOrigin(PN)) : 0;
+ size_t NumValues = PN->getNumIncomingValues();
+ for (size_t v = 0; v < NumValues; v++) {
+ PNS->addIncoming(getShadow(PN, v), PN->getIncomingBlock(v));
+ if (PNO)
+ PNO->addIncoming(getOrigin(PN, v), PN->getIncomingBlock(v));
+ }
+ }
+
+ VAHelper->finalizeInstrumentation();
+
+ materializeChecks();
+
+ return true;
+ }
+
+ /// \brief Compute the shadow type that corresponds to a given Value.
+ Type *getShadowTy(Value *V) {
+ return getShadowTy(V->getType());
+ }
+
+ /// \brief Compute the shadow type that corresponds to a given Type.
+ Type *getShadowTy(Type *OrigTy) {
+ if (!OrigTy->isSized()) {
+ return 0;
+ }
+ // For integer type, shadow is the same as the original type.
+ // This may return weird-sized types like i1.
+ if (IntegerType *IT = dyn_cast<IntegerType>(OrigTy))
+ return IT;
+ if (VectorType *VT = dyn_cast<VectorType>(OrigTy))
+ return VectorType::getInteger(VT);
+ if (StructType *ST = dyn_cast<StructType>(OrigTy)) {
+ SmallVector<Type*, 4> Elements;
+ for (unsigned i = 0, n = ST->getNumElements(); i < n; i++)
+ Elements.push_back(getShadowTy(ST->getElementType(i)));
+ StructType *Res = StructType::get(*MS.C, Elements, ST->isPacked());
+ DEBUG(dbgs() << "getShadowTy: " << *ST << " ===> " << *Res << "\n");
+ return Res;
+ }
+ uint32_t TypeSize = MS.TD->getTypeStoreSizeInBits(OrigTy);
+ return IntegerType::get(*MS.C, TypeSize);
+ }
+
+ /// \brief Flatten a vector type.
+ Type *getShadowTyNoVec(Type *ty) {
+ if (VectorType *vt = dyn_cast<VectorType>(ty))
+ return IntegerType::get(*MS.C, vt->getBitWidth());
+ return ty;
+ }
+
+ /// \brief Convert a shadow value to it's flattened variant.
+ Value *convertToShadowTyNoVec(Value *V, IRBuilder<> &IRB) {
+ Type *Ty = V->getType();
+ Type *NoVecTy = getShadowTyNoVec(Ty);
+ if (Ty == NoVecTy) return V;
+ return IRB.CreateBitCast(V, NoVecTy);
+ }
+
+ /// \brief Compute the shadow address that corresponds to a given application
+ /// address.
+ ///
+ /// Shadow = Addr & ~ShadowMask.
+ Value *getShadowPtr(Value *Addr, Type *ShadowTy,
+ IRBuilder<> &IRB) {
+ Value *ShadowLong =
+ IRB.CreateAnd(IRB.CreatePointerCast(Addr, MS.IntptrTy),
+ ConstantInt::get(MS.IntptrTy, ~MS.ShadowMask));
+ return IRB.CreateIntToPtr(ShadowLong, PointerType::get(ShadowTy, 0));
+ }
+
+ /// \brief Compute the origin address that corresponds to a given application
+ /// address.
+ ///
+ /// OriginAddr = (ShadowAddr + OriginOffset) & ~3ULL
+ /// = Addr & (~ShadowMask & ~3ULL) + OriginOffset
+ Value *getOriginPtr(Value *Addr, IRBuilder<> &IRB) {
+ Value *ShadowLong =
+ IRB.CreateAnd(IRB.CreatePointerCast(Addr, MS.IntptrTy),
+ ConstantInt::get(MS.IntptrTy, ~MS.ShadowMask & ~3ULL));
+ Value *Add =
+ IRB.CreateAdd(ShadowLong,
+ ConstantInt::get(MS.IntptrTy, MS.OriginOffset));
+ return IRB.CreateIntToPtr(Add, PointerType::get(IRB.getInt32Ty(), 0));
+ }
+
+ /// \brief Compute the shadow address for a given function argument.
+ ///
+ /// Shadow = ParamTLS+ArgOffset.
+ Value *getShadowPtrForArgument(Value *A, IRBuilder<> &IRB,
+ int ArgOffset) {
+ Value *Base = IRB.CreatePointerCast(MS.ParamTLS, MS.IntptrTy);
+ Base = IRB.CreateAdd(Base, ConstantInt::get(MS.IntptrTy, ArgOffset));
+ return IRB.CreateIntToPtr(Base, PointerType::get(getShadowTy(A), 0),
+ "_msarg");
+ }
+
+ /// \brief Compute the origin address for a given function argument.
+ Value *getOriginPtrForArgument(Value *A, IRBuilder<> &IRB,
+ int ArgOffset) {
+ if (!ClTrackOrigins) return 0;
+ Value *Base = IRB.CreatePointerCast(MS.ParamOriginTLS, MS.IntptrTy);
+ Base = IRB.CreateAdd(Base, ConstantInt::get(MS.IntptrTy, ArgOffset));
+ return IRB.CreateIntToPtr(Base, PointerType::get(MS.OriginTy, 0),
+ "_msarg_o");
+ }
+
+ /// \brief Compute the shadow address for a retval.
+ Value *getShadowPtrForRetval(Value *A, IRBuilder<> &IRB) {
+ Value *Base = IRB.CreatePointerCast(MS.RetvalTLS, MS.IntptrTy);
+ return IRB.CreateIntToPtr(Base, PointerType::get(getShadowTy(A), 0),
+ "_msret");
+ }
+
+ /// \brief Compute the origin address for a retval.
+ Value *getOriginPtrForRetval(IRBuilder<> &IRB) {
+ // We keep a single origin for the entire retval. Might be too optimistic.
+ return MS.RetvalOriginTLS;
+ }
+
+ /// \brief Set SV to be the shadow value for V.
+ void setShadow(Value *V, Value *SV) {
+ assert(!ShadowMap.count(V) && "Values may only have one shadow");
+ ShadowMap[V] = SV;
+ }
+
+ /// \brief Set Origin to be the origin value for V.
+ void setOrigin(Value *V, Value *Origin) {
+ if (!ClTrackOrigins) return;
+ assert(!OriginMap.count(V) && "Values may only have one origin");
+ DEBUG(dbgs() << "ORIGIN: " << *V << " ==> " << *Origin << "\n");
+ OriginMap[V] = Origin;
+ }
+
+ /// \brief Create a clean shadow value for a given value.
+ ///
+ /// Clean shadow (all zeroes) means all bits of the value are defined
+ /// (initialized).
+ Value *getCleanShadow(Value *V) {
+ Type *ShadowTy = getShadowTy(V);
+ if (!ShadowTy)
+ return 0;
+ return Constant::getNullValue(ShadowTy);
+ }
+
+ /// \brief Create a dirty shadow of a given shadow type.
+ Constant *getPoisonedShadow(Type *ShadowTy) {
+ assert(ShadowTy);
+ if (isa<IntegerType>(ShadowTy) || isa<VectorType>(ShadowTy))
+ return Constant::getAllOnesValue(ShadowTy);
+ StructType *ST = cast<StructType>(ShadowTy);
+ SmallVector<Constant *, 4> Vals;
+ for (unsigned i = 0, n = ST->getNumElements(); i < n; i++)
+ Vals.push_back(getPoisonedShadow(ST->getElementType(i)));
+ return ConstantStruct::get(ST, Vals);
+ }
+
+ /// \brief Create a clean (zero) origin.
+ Value *getCleanOrigin() {
+ return Constant::getNullValue(MS.OriginTy);
+ }
+
+ /// \brief Get the shadow value for a given Value.
+ ///
+ /// This function either returns the value set earlier with setShadow,
+ /// or extracts if from ParamTLS (for function arguments).
+ Value *getShadow(Value *V) {
+ if (Instruction *I = dyn_cast<Instruction>(V)) {
+ // For instructions the shadow is already stored in the map.
+ Value *Shadow = ShadowMap[V];
+ if (!Shadow) {
+ DEBUG(dbgs() << "No shadow: " << *V << "\n" << *(I->getParent()));
+ assert(Shadow && "No shadow for a value");
+ }
+ return Shadow;
+ }
+ if (UndefValue *U = dyn_cast<UndefValue>(V)) {
+ Value *AllOnes = getPoisonedShadow(getShadowTy(V));
+ DEBUG(dbgs() << "Undef: " << *U << " ==> " << *AllOnes << "\n");
+ return AllOnes;
+ }
+ if (Argument *A = dyn_cast<Argument>(V)) {
+ // For arguments we compute the shadow on demand and store it in the map.
+ Value **ShadowPtr = &ShadowMap[V];
+ if (*ShadowPtr)
+ return *ShadowPtr;
+ Function *F = A->getParent();
+ IRBuilder<> EntryIRB(F->getEntryBlock().getFirstNonPHI());
+ unsigned ArgOffset = 0;
+ for (Function::arg_iterator AI = F->arg_begin(), AE = F->arg_end();
+ AI != AE; ++AI) {
+ if (!AI->getType()->isSized()) {
+ DEBUG(dbgs() << "Arg is not sized\n");
+ continue;
+ }
+ unsigned Size = AI->hasByValAttr()
+ ? MS.TD->getTypeAllocSize(AI->getType()->getPointerElementType())
+ : MS.TD->getTypeAllocSize(AI->getType());
+ if (A == AI) {
+ Value *Base = getShadowPtrForArgument(AI, EntryIRB, ArgOffset);
+ if (AI->hasByValAttr()) {
+ // ByVal pointer itself has clean shadow. We copy the actual
+ // argument shadow to the underlying memory.
+ Value *Cpy = EntryIRB.CreateMemCpy(
+ getShadowPtr(V, EntryIRB.getInt8Ty(), EntryIRB),
+ Base, Size, AI->getParamAlignment());
+ DEBUG(dbgs() << " ByValCpy: " << *Cpy << "\n");
+ *ShadowPtr = getCleanShadow(V);
+ } else {
+ *ShadowPtr = EntryIRB.CreateLoad(Base);
+ }
+ DEBUG(dbgs() << " ARG: " << *AI << " ==> " <<
+ **ShadowPtr << "\n");
+ if (ClTrackOrigins) {
+ Value* OriginPtr = getOriginPtrForArgument(AI, EntryIRB, ArgOffset);
+ setOrigin(A, EntryIRB.CreateLoad(OriginPtr));
+ }
+ }
+ ArgOffset += DataLayout::RoundUpAlignment(Size, 8);
+ }
+ assert(*ShadowPtr && "Could not find shadow for an argument");
+ return *ShadowPtr;
+ }
+ // For everything else the shadow is zero.
+ return getCleanShadow(V);
+ }
+
+ /// \brief Get the shadow for i-th argument of the instruction I.
+ Value *getShadow(Instruction *I, int i) {
+ return getShadow(I->getOperand(i));
+ }
+
+ /// \brief Get the origin for a value.
+ Value *getOrigin(Value *V) {
+ if (!ClTrackOrigins) return 0;
+ if (isa<Instruction>(V) || isa<Argument>(V)) {
+ Value *Origin = OriginMap[V];
+ if (!Origin) {
+ DEBUG(dbgs() << "NO ORIGIN: " << *V << "\n");
+ Origin = getCleanOrigin();
+ }
+ return Origin;
+ }
+ return getCleanOrigin();
+ }
+
+ /// \brief Get the origin for i-th argument of the instruction I.
+ Value *getOrigin(Instruction *I, int i) {
+ return getOrigin(I->getOperand(i));
+ }
+
+ /// \brief Remember the place where a shadow check should be inserted.
+ ///
+ /// This location will be later instrumented with a check that will print a
+ /// UMR warning in runtime if the value is not fully defined.
+ void insertCheck(Value *Val, Instruction *OrigIns) {
+ assert(Val);
+ if (!InsertChecks) return;
+ Instruction *Shadow = dyn_cast_or_null<Instruction>(getShadow(Val));
+ if (!Shadow) return;
+ Type *ShadowTy = Shadow->getType();
+ assert((isa<IntegerType>(ShadowTy) || isa<VectorType>(ShadowTy)) &&
+ "Can only insert checks for integer and vector shadow types");
+ Instruction *Origin = dyn_cast_or_null<Instruction>(getOrigin(Val));
+ InstrumentationList.push_back(
+ ShadowOriginAndInsertPoint(Shadow, Origin, OrigIns));
+ }
+
+ //------------------- Visitors.
+
+ /// \brief Instrument LoadInst
+ ///
+ /// Loads the corresponding shadow and (optionally) origin.
+ /// Optionally, checks that the load address is fully defined.
+ void visitLoadInst(LoadInst &I) {
+ Type *LoadTy = I.getType();
+ assert(LoadTy->isSized() && "Load type must have size");
+ IRBuilder<> IRB(&I);
+ Type *ShadowTy = getShadowTy(&I);
+ Value *Addr = I.getPointerOperand();
+ Value *ShadowPtr = getShadowPtr(Addr, ShadowTy, IRB);
+ setShadow(&I, IRB.CreateLoad(ShadowPtr, "_msld"));
+
+ if (ClCheckAccessAddress)
+ insertCheck(I.getPointerOperand(), &I);
+
+ if (ClTrackOrigins)
+ setOrigin(&I, IRB.CreateLoad(getOriginPtr(Addr, IRB)));
+ }
+
+ /// \brief Instrument StoreInst
+ ///
+ /// Stores the corresponding shadow and (optionally) origin.
+ /// Optionally, checks that the store address is fully defined.
+ /// Volatile stores check that the value being stored is fully defined.
+ void visitStoreInst(StoreInst &I) {
+ IRBuilder<> IRB(&I);
+ Value *Val = I.getValueOperand();
+ Value *Addr = I.getPointerOperand();
+ Value *Shadow = getShadow(Val);
+ Value *ShadowPtr = getShadowPtr(Addr, Shadow->getType(), IRB);
+
+ StoreInst *NewSI = IRB.CreateStore(Shadow, ShadowPtr);
+ DEBUG(dbgs() << " STORE: " << *NewSI << "\n");
+ // If the store is volatile, add a check.
+ if (I.isVolatile())
+ insertCheck(Val, &I);
+ if (ClCheckAccessAddress)
+ insertCheck(Addr, &I);
+
+ if (ClTrackOrigins)
+ IRB.CreateStore(getOrigin(Val), getOriginPtr(Addr, IRB));
+ }
+
+ // Casts.
+ void visitSExtInst(SExtInst &I) {
+ IRBuilder<> IRB(&I);
+ setShadow(&I, IRB.CreateSExt(getShadow(&I, 0), I.getType(), "_msprop"));
+ setOrigin(&I, getOrigin(&I, 0));
+ }
+
+ void visitZExtInst(ZExtInst &I) {
+ IRBuilder<> IRB(&I);
+ setShadow(&I, IRB.CreateZExt(getShadow(&I, 0), I.getType(), "_msprop"));
+ setOrigin(&I, getOrigin(&I, 0));
+ }
+
+ void visitTruncInst(TruncInst &I) {
+ IRBuilder<> IRB(&I);
+ setShadow(&I, IRB.CreateTrunc(getShadow(&I, 0), I.getType(), "_msprop"));
+ setOrigin(&I, getOrigin(&I, 0));
+ }
+
+ void visitBitCastInst(BitCastInst &I) {
+ IRBuilder<> IRB(&I);
+ setShadow(&I, IRB.CreateBitCast(getShadow(&I, 0), getShadowTy(&I)));
+ setOrigin(&I, getOrigin(&I, 0));
+ }
+
+ void visitPtrToIntInst(PtrToIntInst &I) {
+ IRBuilder<> IRB(&I);
+ setShadow(&I, IRB.CreateIntCast(getShadow(&I, 0), getShadowTy(&I), false,
+ "_msprop_ptrtoint"));
+ setOrigin(&I, getOrigin(&I, 0));
+ }
+
+ void visitIntToPtrInst(IntToPtrInst &I) {
+ IRBuilder<> IRB(&I);
+ setShadow(&I, IRB.CreateIntCast(getShadow(&I, 0), getShadowTy(&I), false,
+ "_msprop_inttoptr"));
+ setOrigin(&I, getOrigin(&I, 0));
+ }
+
+ void visitFPToSIInst(CastInst& I) { handleShadowOr(I); }
+ void visitFPToUIInst(CastInst& I) { handleShadowOr(I); }
+ void visitSIToFPInst(CastInst& I) { handleShadowOr(I); }
+ void visitUIToFPInst(CastInst& I) { handleShadowOr(I); }
+ void visitFPExtInst(CastInst& I) { handleShadowOr(I); }
+ void visitFPTruncInst(CastInst& I) { handleShadowOr(I); }
+
+ /// \brief Propagate shadow for bitwise AND.
+ ///
+ /// This code is exact, i.e. if, for example, a bit in the left argument
+ /// is defined and 0, then neither the value not definedness of the
+ /// corresponding bit in B don't affect the resulting shadow.
+ void visitAnd(BinaryOperator &I) {
+ IRBuilder<> IRB(&I);
+ // "And" of 0 and a poisoned value results in unpoisoned value.
+ // 1&1 => 1; 0&1 => 0; p&1 => p;
+ // 1&0 => 0; 0&0 => 0; p&0 => 0;
+ // 1&p => p; 0&p => 0; p&p => p;
+ // S = (S1 & S2) | (V1 & S2) | (S1 & V2)
+ Value *S1 = getShadow(&I, 0);
+ Value *S2 = getShadow(&I, 1);
+ Value *V1 = I.getOperand(0);
+ Value *V2 = I.getOperand(1);
+ if (V1->getType() != S1->getType()) {
+ V1 = IRB.CreateIntCast(V1, S1->getType(), false);
+ V2 = IRB.CreateIntCast(V2, S2->getType(), false);
+ }
+ Value *S1S2 = IRB.CreateAnd(S1, S2);
+ Value *V1S2 = IRB.CreateAnd(V1, S2);
+ Value *S1V2 = IRB.CreateAnd(S1, V2);
+ setShadow(&I, IRB.CreateOr(S1S2, IRB.CreateOr(V1S2, S1V2)));
+ setOriginForNaryOp(I);
+ }
+
+ void visitOr(BinaryOperator &I) {
+ IRBuilder<> IRB(&I);
+ // "Or" of 1 and a poisoned value results in unpoisoned value.
+ // 1|1 => 1; 0|1 => 1; p|1 => 1;
+ // 1|0 => 1; 0|0 => 0; p|0 => p;
+ // 1|p => 1; 0|p => p; p|p => p;
+ // S = (S1 & S2) | (~V1 & S2) | (S1 & ~V2)
+ Value *S1 = getShadow(&I, 0);
+ Value *S2 = getShadow(&I, 1);
+ Value *V1 = IRB.CreateNot(I.getOperand(0));
+ Value *V2 = IRB.CreateNot(I.getOperand(1));
+ if (V1->getType() != S1->getType()) {
+ V1 = IRB.CreateIntCast(V1, S1->getType(), false);
+ V2 = IRB.CreateIntCast(V2, S2->getType(), false);
+ }
+ Value *S1S2 = IRB.CreateAnd(S1, S2);
+ Value *V1S2 = IRB.CreateAnd(V1, S2);
+ Value *S1V2 = IRB.CreateAnd(S1, V2);
+ setShadow(&I, IRB.CreateOr(S1S2, IRB.CreateOr(V1S2, S1V2)));
+ setOriginForNaryOp(I);
+ }
+
+ /// \brief Propagate origin for an instruction.
+ ///
+ /// This is a general case of origin propagation. For an Nary operation,
+ /// is set to the origin of an argument that is not entirely initialized.
+ /// It does not matter which one is picked if all arguments are initialized.
+ void setOriginForNaryOp(Instruction &I) {
+ if (!ClTrackOrigins) return;
+ IRBuilder<> IRB(&I);
+ Value *Origin = getOrigin(&I, 0);
+ for (unsigned Op = 1, n = I.getNumOperands(); Op < n; ++Op) {
+ Value *S = convertToShadowTyNoVec(getShadow(&I, Op - 1), IRB);
+ Origin = IRB.CreateSelect(IRB.CreateICmpNE(S, getCleanShadow(S)),
+ Origin, getOrigin(&I, Op));
+ }
+ setOrigin(&I, Origin);
+ }
+
+ /// \brief Propagate shadow for a binary operation.
+ ///
+ /// Shadow = Shadow0 | Shadow1, all 3 must have the same type.
+ /// Bitwise OR is selected as an operation that will never lose even a bit of
+ /// poison.
+ void handleShadowOrBinary(Instruction &I) {
+ IRBuilder<> IRB(&I);
+ Value *Shadow0 = getShadow(&I, 0);
+ Value *Shadow1 = getShadow(&I, 1);
+ setShadow(&I, IRB.CreateOr(Shadow0, Shadow1, "_msprop"));
+ setOriginForNaryOp(I);
+ }
+
+ /// \brief Propagate shadow for arbitrary operation.
+ ///
+ /// This is a general case of shadow propagation, used in all cases where we
+ /// don't know and/or care about what the operation actually does.
+ /// It converts all input shadow values to a common type (extending or
+ /// truncating as necessary), and bitwise OR's them.
+ ///
+ /// This is much cheaper than inserting checks (i.e. requiring inputs to be
+ /// fully initialized), and less prone to false positives.
+ // FIXME: is the casting actually correct?
+ // FIXME: merge this with handleShadowOrBinary.
+ void handleShadowOr(Instruction &I) {
+ IRBuilder<> IRB(&I);
+ Value *Shadow = getShadow(&I, 0);
+ for (unsigned Op = 1, n = I.getNumOperands(); Op < n; ++Op)
+ Shadow = IRB.CreateOr(
+ Shadow, IRB.CreateIntCast(getShadow(&I, Op), Shadow->getType(), false),
+ "_msprop");
+ Shadow = IRB.CreateIntCast(Shadow, getShadowTy(&I), false);
+ setShadow(&I, Shadow);
+ setOriginForNaryOp(I);
+ }
+
+ void visitFAdd(BinaryOperator &I) { handleShadowOrBinary(I); }
+ void visitFSub(BinaryOperator &I) { handleShadowOrBinary(I); }
+ void visitFMul(BinaryOperator &I) { handleShadowOrBinary(I); }
+ void visitAdd(BinaryOperator &I) { handleShadowOrBinary(I); }
+ void visitSub(BinaryOperator &I) { handleShadowOrBinary(I); }
+ void visitXor(BinaryOperator &I) { handleShadowOrBinary(I); }
+ void visitMul(BinaryOperator &I) { handleShadowOrBinary(I); }
+
+ void handleDiv(Instruction &I) {
+ IRBuilder<> IRB(&I);
+ // Strict on the second argument.
+ insertCheck(I.getOperand(1), &I);
+ setShadow(&I, getShadow(&I, 0));
+ setOrigin(&I, getOrigin(&I, 0));
+ }
+
+ void visitUDiv(BinaryOperator &I) { handleDiv(I); }
+ void visitSDiv(BinaryOperator &I) { handleDiv(I); }
+ void visitFDiv(BinaryOperator &I) { handleDiv(I); }
+ void visitURem(BinaryOperator &I) { handleDiv(I); }
+ void visitSRem(BinaryOperator &I) { handleDiv(I); }
+ void visitFRem(BinaryOperator &I) { handleDiv(I); }
+
+ /// \brief Instrument == and != comparisons.
+ ///
+ /// Sometimes the comparison result is known even if some of the bits of the
+ /// arguments are not.
+ void handleEqualityComparison(ICmpInst &I) {
+ IRBuilder<> IRB(&I);
+ Value *A = I.getOperand(0);
+ Value *B = I.getOperand(1);
+ Value *Sa = getShadow(A);
+ Value *Sb = getShadow(B);
+ if (A->getType()->isPointerTy())
+ A = IRB.CreatePointerCast(A, MS.IntptrTy);
+ if (B->getType()->isPointerTy())
+ B = IRB.CreatePointerCast(B, MS.IntptrTy);
+ // A == B <==> (C = A^B) == 0
+ // A != B <==> (C = A^B) != 0
+ // Sc = Sa | Sb
+ Value *C = IRB.CreateXor(A, B);
+ Value *Sc = IRB.CreateOr(Sa, Sb);
+ // Now dealing with i = (C == 0) comparison (or C != 0, does not matter now)
+ // Result is defined if one of the following is true
+ // * there is a defined 1 bit in C
+ // * C is fully defined
+ // Si = !(C & ~Sc) && Sc
+ Value *Zero = Constant::getNullValue(Sc->getType());
+ Value *MinusOne = Constant::getAllOnesValue(Sc->getType());
+ Value *Si =
+ IRB.CreateAnd(IRB.CreateICmpNE(Sc, Zero),
+ IRB.CreateICmpEQ(
+ IRB.CreateAnd(IRB.CreateXor(Sc, MinusOne), C), Zero));
+ Si->setName("_msprop_icmp");
+ setShadow(&I, Si);
+ setOriginForNaryOp(I);
+ }
+
+ void visitICmpInst(ICmpInst &I) {
+ if (ClHandleICmp && I.isEquality())
+ handleEqualityComparison(I);
+ else
+ handleShadowOr(I);
+ }
+
+ void visitFCmpInst(FCmpInst &I) {
+ handleShadowOr(I);
+ }
+
+ void handleShift(BinaryOperator &I) {
+ IRBuilder<> IRB(&I);
+ // If any of the S2 bits are poisoned, the whole thing is poisoned.
+ // Otherwise perform the same shift on S1.
+ Value *S1 = getShadow(&I, 0);
+ Value *S2 = getShadow(&I, 1);
+ Value *S2Conv = IRB.CreateSExt(IRB.CreateICmpNE(S2, getCleanShadow(S2)),
+ S2->getType());
+ Value *V2 = I.getOperand(1);
+ Value *Shift = IRB.CreateBinOp(I.getOpcode(), S1, V2);
+ setShadow(&I, IRB.CreateOr(Shift, S2Conv));
+ setOriginForNaryOp(I);
+ }
+
+ void visitShl(BinaryOperator &I) { handleShift(I); }
+ void visitAShr(BinaryOperator &I) { handleShift(I); }
+ void visitLShr(BinaryOperator &I) { handleShift(I); }
+
+ void visitMemSetInst(MemSetInst &I) {
+ IRBuilder<> IRB(&I);
+ Value *Ptr = I.getArgOperand(0);
+ Value *Val = I.getArgOperand(1);
+ Value *ShadowPtr = getShadowPtr(Ptr, Val->getType(), IRB);
+ Value *ShadowVal = getCleanShadow(Val);
+ Value *Size = I.getArgOperand(2);
+ unsigned Align = I.getAlignment();
+ bool isVolatile = I.isVolatile();
+
+ IRB.CreateMemSet(ShadowPtr, ShadowVal, Size, Align, isVolatile);
+ }
+
+ void visitMemCpyInst(MemCpyInst &I) {
+ IRBuilder<> IRB(&I);
+ Value *Dst = I.getArgOperand(0);
+ Value *Src = I.getArgOperand(1);
+ Type *ElementType = dyn_cast<PointerType>(Dst->getType())->getElementType();
+ Value *ShadowDst = getShadowPtr(Dst, ElementType, IRB);
+ Value *ShadowSrc = getShadowPtr(Src, ElementType, IRB);
+ Value *Size = I.getArgOperand(2);
+ unsigned Align = I.getAlignment();
+ bool isVolatile = I.isVolatile();
+
+ IRB.CreateMemCpy(ShadowDst, ShadowSrc, Size, Align, isVolatile);
+ if (ClTrackOrigins)
+ IRB.CreateCall3(MS.MsanCopyOriginFn, Dst, Src, Size);
+ }
+
+ /// \brief Instrument llvm.memmove
+ ///
+ /// At this point we don't know if llvm.memmove will be inlined or not.
+ /// If we don't instrument it and it gets inlined,
+ /// our interceptor will not kick in and we will lose the memmove.
+ /// If we instrument the call here, but it does not get inlined,
+ /// we will memove the shadow twice: which is bad in case
+ /// of overlapping regions. So, we simply lower the intrinsic to a call.
+ ///
+ /// Similar situation exists for memcpy and memset, but for those functions
+ /// calling instrumentation twice does not lead to incorrect results.
+ void visitMemMoveInst(MemMoveInst &I) {
+ IRBuilder<> IRB(&I);
+ IRB.CreateCall3(
+ MS.MemmoveFn,
+ IRB.CreatePointerCast(I.getArgOperand(0), IRB.getInt8PtrTy()),
+ IRB.CreatePointerCast(I.getArgOperand(1), IRB.getInt8PtrTy()),
+ IRB.CreateIntCast(I.getArgOperand(2), MS.IntptrTy, false));
+ I.eraseFromParent();
+ }
+
+ void visitVAStartInst(VAStartInst &I) {
+ VAHelper->visitVAStartInst(I);
+ }
+
+ void visitVACopyInst(VACopyInst &I) {
+ VAHelper->visitVACopyInst(I);
+ }
+
+ void visitCallSite(CallSite CS) {
+ Instruction &I = *CS.getInstruction();
+ assert((CS.isCall() || CS.isInvoke()) && "Unknown type of CallSite");
+ if (CS.isCall()) {
+ // Allow only tail calls with the same types, otherwise
+ // we may have a false positive: shadow for a non-void RetVal
+ // will get propagated to a void RetVal.
+ CallInst *Call = cast<CallInst>(&I);
+ if (Call->isTailCall() && Call->getType() != Call->getParent()->getType())
+ Call->setTailCall(false);
+ if (isa<IntrinsicInst>(&I)) {
+ // All intrinsics we care about are handled in corresponding visit*
+ // methods. Add checks for the arguments, mark retval as clean.
+ visitInstruction(I);
+ return;
+ }
+ }
+ IRBuilder<> IRB(&I);
+ unsigned ArgOffset = 0;
+ DEBUG(dbgs() << " CallSite: " << I << "\n");
+ for (CallSite::arg_iterator ArgIt = CS.arg_begin(), End = CS.arg_end();
+ ArgIt != End; ++ArgIt) {
+ Value *A = *ArgIt;
+ unsigned i = ArgIt - CS.arg_begin();
+ if (!A->getType()->isSized()) {
+ DEBUG(dbgs() << "Arg " << i << " is not sized: " << I << "\n");
+ continue;
+ }
+ unsigned Size = 0;
+ Value *Store = 0;
+ // Compute the Shadow for arg even if it is ByVal, because
+ // in that case getShadow() will copy the actual arg shadow to
+ // __msan_param_tls.
+ Value *ArgShadow = getShadow(A);
+ Value *ArgShadowBase = getShadowPtrForArgument(A, IRB, ArgOffset);
+ DEBUG(dbgs() << " Arg#" << i << ": " << *A <<
+ " Shadow: " << *ArgShadow << "\n");
+ if (CS.paramHasAttr(i + 1, Attributes::ByVal)) {
+ assert(A->getType()->isPointerTy() &&
+ "ByVal argument is not a pointer!");
+ Size = MS.TD->getTypeAllocSize(A->getType()->getPointerElementType());
+ unsigned Alignment = CS.getParamAlignment(i + 1);
+ Store = IRB.CreateMemCpy(ArgShadowBase,
+ getShadowPtr(A, Type::getInt8Ty(*MS.C), IRB),
+ Size, Alignment);
+ } else {
+ Size = MS.TD->getTypeAllocSize(A->getType());
+ Store = IRB.CreateStore(ArgShadow, ArgShadowBase);
+ }
+ if (ClTrackOrigins)
+ IRB.CreateStore(getOrigin(A),
+ getOriginPtrForArgument(A, IRB, ArgOffset));
+ assert(Size != 0 && Store != 0);
+ DEBUG(dbgs() << " Param:" << *Store << "\n");
+ ArgOffset += DataLayout::RoundUpAlignment(Size, 8);
+ }
+ DEBUG(dbgs() << " done with call args\n");
+
+ FunctionType *FT =
+ cast<FunctionType>(CS.getCalledValue()->getType()-> getContainedType(0));
+ if (FT->isVarArg()) {
+ VAHelper->visitCallSite(CS, IRB);
+ }
+
+ // Now, get the shadow for the RetVal.
+ if (!I.getType()->isSized()) return;
+ IRBuilder<> IRBBefore(&I);
+ // Untill we have full dynamic coverage, make sure the retval shadow is 0.
+ Value *Base = getShadowPtrForRetval(&I, IRBBefore);
+ IRBBefore.CreateStore(getCleanShadow(&I), Base);
+ Instruction *NextInsn = 0;
+ if (CS.isCall()) {
+ NextInsn = I.getNextNode();
+ } else {
+ BasicBlock *NormalDest = cast<InvokeInst>(&I)->getNormalDest();
+ if (!NormalDest->getSinglePredecessor()) {
+ // FIXME: this case is tricky, so we are just conservative here.
+ // Perhaps we need to split the edge between this BB and NormalDest,
+ // but a naive attempt to use SplitEdge leads to a crash.
+ setShadow(&I, getCleanShadow(&I));
+ setOrigin(&I, getCleanOrigin());
+ return;
+ }
+ NextInsn = NormalDest->getFirstInsertionPt();
+ assert(NextInsn &&
+ "Could not find insertion point for retval shadow load");
+ }
+ IRBuilder<> IRBAfter(NextInsn);
+ setShadow(&I, IRBAfter.CreateLoad(getShadowPtrForRetval(&I, IRBAfter),
+ "_msret"));
+ if (ClTrackOrigins)
+ setOrigin(&I, IRBAfter.CreateLoad(getOriginPtrForRetval(IRBAfter)));
+ }
+
+ void visitReturnInst(ReturnInst &I) {
+ IRBuilder<> IRB(&I);
+ if (Value *RetVal = I.getReturnValue()) {
+ // Set the shadow for the RetVal.
+ Value *Shadow = getShadow(RetVal);
+ Value *ShadowPtr = getShadowPtrForRetval(RetVal, IRB);
+ DEBUG(dbgs() << "Return: " << *Shadow << "\n" << *ShadowPtr << "\n");
+ IRB.CreateStore(Shadow, ShadowPtr);
+ if (ClTrackOrigins)
+ IRB.CreateStore(getOrigin(RetVal), getOriginPtrForRetval(IRB));
+ }
+ }
+
+ void visitPHINode(PHINode &I) {
+ IRBuilder<> IRB(&I);
+ ShadowPHINodes.push_back(&I);
+ setShadow(&I, IRB.CreatePHI(getShadowTy(&I), I.getNumIncomingValues(),
+ "_msphi_s"));
+ if (ClTrackOrigins)
+ setOrigin(&I, IRB.CreatePHI(MS.OriginTy, I.getNumIncomingValues(),
+ "_msphi_o"));
+ }
+
+ void visitAllocaInst(AllocaInst &I) {
+ setShadow(&I, getCleanShadow(&I));
+ if (!ClPoisonStack) return;
+ IRBuilder<> IRB(I.getNextNode());
+ uint64_t Size = MS.TD->getTypeAllocSize(I.getAllocatedType());
+ if (ClPoisonStackWithCall) {
+ IRB.CreateCall2(MS.MsanPoisonStackFn,
+ IRB.CreatePointerCast(&I, IRB.getInt8PtrTy()),
+ ConstantInt::get(MS.IntptrTy, Size));
+ } else {
+ Value *ShadowBase = getShadowPtr(&I, Type::getInt8PtrTy(*MS.C), IRB);
+ IRB.CreateMemSet(ShadowBase, IRB.getInt8(ClPoisonStackPattern),
+ Size, I.getAlignment());
+ }
+
+ if (ClTrackOrigins) {
+ setOrigin(&I, getCleanOrigin());
+ SmallString<2048> StackDescriptionStorage;
+ raw_svector_ostream StackDescription(StackDescriptionStorage);
+ // We create a string with a description of the stack allocation and
+ // pass it into __msan_set_alloca_origin.
+ // It will be printed by the run-time if stack-originated UMR is found.
+ // The first 4 bytes of the string are set to '----' and will be replaced
+ // by __msan_va_arg_overflow_size_tls at the first call.
+ StackDescription << "----" << I.getName() << "@" << F.getName();
+ Value *Descr =
+ createPrivateNonConstGlobalForString(*F.getParent(),
+ StackDescription.str());
+ IRB.CreateCall3(MS.MsanSetAllocaOriginFn,
+ IRB.CreatePointerCast(&I, IRB.getInt8PtrTy()),
+ ConstantInt::get(MS.IntptrTy, Size),
+ IRB.CreatePointerCast(Descr, IRB.getInt8PtrTy()));
+ }
+ }
+
+ void visitSelectInst(SelectInst& I) {
+ IRBuilder<> IRB(&I);
+ setShadow(&I, IRB.CreateSelect(I.getCondition(),
+ getShadow(I.getTrueValue()), getShadow(I.getFalseValue()),
+ "_msprop"));
+ if (ClTrackOrigins)
+ setOrigin(&I, IRB.CreateSelect(I.getCondition(),
+ getOrigin(I.getTrueValue()), getOrigin(I.getFalseValue())));
+ }
+
+ void visitLandingPadInst(LandingPadInst &I) {
+ // Do nothing.
+ // See http://code.google.com/p/memory-sanitizer/issues/detail?id=1
+ setShadow(&I, getCleanShadow(&I));
+ setOrigin(&I, getCleanOrigin());
+ }
+
+ void visitGetElementPtrInst(GetElementPtrInst &I) {
+ handleShadowOr(I);
+ }
+
+ void visitExtractValueInst(ExtractValueInst &I) {
+ IRBuilder<> IRB(&I);
+ Value *Agg = I.getAggregateOperand();
+ DEBUG(dbgs() << "ExtractValue: " << I << "\n");
+ Value *AggShadow = getShadow(Agg);
+ DEBUG(dbgs() << " AggShadow: " << *AggShadow << "\n");
+ Value *ResShadow = IRB.CreateExtractValue(AggShadow, I.getIndices());
+ DEBUG(dbgs() << " ResShadow: " << *ResShadow << "\n");
+ setShadow(&I, ResShadow);
+ setOrigin(&I, getCleanOrigin());
+ }
+
+ void visitInsertValueInst(InsertValueInst &I) {
+ IRBuilder<> IRB(&I);
+ DEBUG(dbgs() << "InsertValue: " << I << "\n");
+ Value *AggShadow = getShadow(I.getAggregateOperand());
+ Value *InsShadow = getShadow(I.getInsertedValueOperand());
+ DEBUG(dbgs() << " AggShadow: " << *AggShadow << "\n");
+ DEBUG(dbgs() << " InsShadow: " << *InsShadow << "\n");
+ Value *Res = IRB.CreateInsertValue(AggShadow, InsShadow, I.getIndices());
+ DEBUG(dbgs() << " Res: " << *Res << "\n");
+ setShadow(&I, Res);
+ setOrigin(&I, getCleanOrigin());
+ }
+
+ void dumpInst(Instruction &I) {
+ if (CallInst *CI = dyn_cast<CallInst>(&I)) {
+ errs() << "ZZZ call " << CI->getCalledFunction()->getName() << "\n";
+ } else {
+ errs() << "ZZZ " << I.getOpcodeName() << "\n";
+ }
+ errs() << "QQQ " << I << "\n";
+ }
+
+ void visitResumeInst(ResumeInst &I) {
+ DEBUG(dbgs() << "Resume: " << I << "\n");
+ // Nothing to do here.
+ }
+
+ void visitInstruction(Instruction &I) {
+ // Everything else: stop propagating and check for poisoned shadow.
+ if (ClDumpStrictInstructions)
+ dumpInst(I);
+ DEBUG(dbgs() << "DEFAULT: " << I << "\n");
+ for (size_t i = 0, n = I.getNumOperands(); i < n; i++)
+ insertCheck(I.getOperand(i), &I);
+ setShadow(&I, getCleanShadow(&I));
+ setOrigin(&I, getCleanOrigin());
+ }
+};
+
+/// \brief AMD64-specific implementation of VarArgHelper.
+struct VarArgAMD64Helper : public VarArgHelper {
+ // An unfortunate workaround for asymmetric lowering of va_arg stuff.
+ // See a comment in visitCallSite for more details.
+ static const unsigned AMD64GpEndOffset = 48; // AMD64 ABI Draft 0.99.6 p3.5.7
+ static const unsigned AMD64FpEndOffset = 176;
+
+ Function &F;
+ MemorySanitizer &MS;
+ MemorySanitizerVisitor &MSV;
+ Value *VAArgTLSCopy;
+ Value *VAArgOverflowSize;
+
+ SmallVector<CallInst*, 16> VAStartInstrumentationList;
+
+ VarArgAMD64Helper(Function &F, MemorySanitizer &MS,
+ MemorySanitizerVisitor &MSV)
+ : F(F), MS(MS), MSV(MSV), VAArgTLSCopy(0), VAArgOverflowSize(0) { }
+
+ enum ArgKind { AK_GeneralPurpose, AK_FloatingPoint, AK_Memory };
+
+ ArgKind classifyArgument(Value* arg) {
+ // A very rough approximation of X86_64 argument classification rules.
+ Type *T = arg->getType();
+ if (T->isFPOrFPVectorTy() || T->isX86_MMXTy())
+ return AK_FloatingPoint;
+ if (T->isIntegerTy() && T->getPrimitiveSizeInBits() <= 64)
+ return AK_GeneralPurpose;
+ if (T->isPointerTy())
+ return AK_GeneralPurpose;
+ return AK_Memory;
+ }
+
+ // For VarArg functions, store the argument shadow in an ABI-specific format
+ // that corresponds to va_list layout.
+ // We do this because Clang lowers va_arg in the frontend, and this pass
+ // only sees the low level code that deals with va_list internals.
+ // A much easier alternative (provided that Clang emits va_arg instructions)
+ // would have been to associate each live instance of va_list with a copy of
+ // MSanParamTLS, and extract shadow on va_arg() call in the argument list
+ // order.
+ void visitCallSite(CallSite &CS, IRBuilder<> &IRB) {
+ unsigned GpOffset = 0;
+ unsigned FpOffset = AMD64GpEndOffset;
+ unsigned OverflowOffset = AMD64FpEndOffset;
+ for (CallSite::arg_iterator ArgIt = CS.arg_begin(), End = CS.arg_end();
+ ArgIt != End; ++ArgIt) {
+ Value *A = *ArgIt;
+ ArgKind AK = classifyArgument(A);
+ if (AK == AK_GeneralPurpose && GpOffset >= AMD64GpEndOffset)
+ AK = AK_Memory;
+ if (AK == AK_FloatingPoint && FpOffset >= AMD64FpEndOffset)
+ AK = AK_Memory;
+ Value *Base;
+ switch (AK) {
+ case AK_GeneralPurpose:
+ Base = getShadowPtrForVAArgument(A, IRB, GpOffset);
+ GpOffset += 8;
+ break;
+ case AK_FloatingPoint:
+ Base = getShadowPtrForVAArgument(A, IRB, FpOffset);
+ FpOffset += 16;
+ break;
+ case AK_Memory:
+ uint64_t ArgSize = MS.TD->getTypeAllocSize(A->getType());
+ Base = getShadowPtrForVAArgument(A, IRB, OverflowOffset);
+ OverflowOffset += DataLayout::RoundUpAlignment(ArgSize, 8);
+ }
+ IRB.CreateStore(MSV.getShadow(A), Base);
+ }
+ Constant *OverflowSize =
+ ConstantInt::get(IRB.getInt64Ty(), OverflowOffset - AMD64FpEndOffset);
+ IRB.CreateStore(OverflowSize, MS.VAArgOverflowSizeTLS);
+ }
+
+ /// \brief Compute the shadow address for a given va_arg.
+ Value *getShadowPtrForVAArgument(Value *A, IRBuilder<> &IRB,
+ int ArgOffset) {
+ Value *Base = IRB.CreatePointerCast(MS.VAArgTLS, MS.IntptrTy);
+ Base = IRB.CreateAdd(Base, ConstantInt::get(MS.IntptrTy, ArgOffset));
+ return IRB.CreateIntToPtr(Base, PointerType::get(MSV.getShadowTy(A), 0),
+ "_msarg");
+ }
+
+ void visitVAStartInst(VAStartInst &I) {
+ IRBuilder<> IRB(&I);
+ VAStartInstrumentationList.push_back(&I);
+ Value *VAListTag = I.getArgOperand(0);
+ Value *ShadowPtr = MSV.getShadowPtr(VAListTag, IRB.getInt8Ty(), IRB);
+
+ // Unpoison the whole __va_list_tag.
+ // FIXME: magic ABI constants.
+ IRB.CreateMemSet(ShadowPtr, Constant::getNullValue(IRB.getInt8Ty()),
+ /* size */24, /* alignment */16, false);
+ }
+
+ void visitVACopyInst(VACopyInst &I) {
+ IRBuilder<> IRB(&I);
+ Value *VAListTag = I.getArgOperand(0);
+ Value *ShadowPtr = MSV.getShadowPtr(VAListTag, IRB.getInt8Ty(), IRB);
+
+ // Unpoison the whole __va_list_tag.
+ // FIXME: magic ABI constants.
+ IRB.CreateMemSet(ShadowPtr, Constant::getNullValue(IRB.getInt8Ty()),
+ /* size */ 24, /* alignment */ 16, false);
+ }
+
+ void finalizeInstrumentation() {
+ assert(!VAArgOverflowSize && !VAArgTLSCopy &&
+ "finalizeInstrumentation called twice");
+ if (!VAStartInstrumentationList.empty()) {
+ // If there is a va_start in this function, make a backup copy of
+ // va_arg_tls somewhere in the function entry block.
+ IRBuilder<> IRB(F.getEntryBlock().getFirstNonPHI());
+ VAArgOverflowSize = IRB.CreateLoad(MS.VAArgOverflowSizeTLS);
+ Value *CopySize =
+ IRB.CreateAdd(ConstantInt::get(MS.IntptrTy, AMD64FpEndOffset),
+ VAArgOverflowSize);
+ VAArgTLSCopy = IRB.CreateAlloca(Type::getInt8Ty(*MS.C), CopySize);
+ IRB.CreateMemCpy(VAArgTLSCopy, MS.VAArgTLS, CopySize, 8);
+ }
+
+ // Instrument va_start.
+ // Copy va_list shadow from the backup copy of the TLS contents.
+ for (size_t i = 0, n = VAStartInstrumentationList.size(); i < n; i++) {
+ CallInst *OrigInst = VAStartInstrumentationList[i];
+ IRBuilder<> IRB(OrigInst->getNextNode());
+ Value *VAListTag = OrigInst->getArgOperand(0);
+
+ Value *RegSaveAreaPtrPtr =
+ IRB.CreateIntToPtr(
+ IRB.CreateAdd(IRB.CreatePtrToInt(VAListTag, MS.IntptrTy),
+ ConstantInt::get(MS.IntptrTy, 16)),
+ Type::getInt64PtrTy(*MS.C));
+ Value *RegSaveAreaPtr = IRB.CreateLoad(RegSaveAreaPtrPtr);
+ Value *RegSaveAreaShadowPtr =
+ MSV.getShadowPtr(RegSaveAreaPtr, IRB.getInt8Ty(), IRB);
+ IRB.CreateMemCpy(RegSaveAreaShadowPtr, VAArgTLSCopy,
+ AMD64FpEndOffset, 16);
+
+ Value *OverflowArgAreaPtrPtr =
+ IRB.CreateIntToPtr(
+ IRB.CreateAdd(IRB.CreatePtrToInt(VAListTag, MS.IntptrTy),
+ ConstantInt::get(MS.IntptrTy, 8)),
+ Type::getInt64PtrTy(*MS.C));
+ Value *OverflowArgAreaPtr = IRB.CreateLoad(OverflowArgAreaPtrPtr);
+ Value *OverflowArgAreaShadowPtr =
+ MSV.getShadowPtr(OverflowArgAreaPtr, IRB.getInt8Ty(), IRB);
+ Value *SrcPtr =
+ getShadowPtrForVAArgument(VAArgTLSCopy, IRB, AMD64FpEndOffset);
+ IRB.CreateMemCpy(OverflowArgAreaShadowPtr, SrcPtr, VAArgOverflowSize, 16);
+ }
+ }
+};
+
+VarArgHelper* CreateVarArgHelper(Function &Func, MemorySanitizer &Msan,
+ MemorySanitizerVisitor &Visitor) {
+ return new VarArgAMD64Helper(Func, Msan, Visitor);
+}
+
+} // namespace
+
+bool MemorySanitizer::runOnFunction(Function &F) {
+ MemorySanitizerVisitor Visitor(F, *this);
+
+ // Clear out readonly/readnone attributes.
+ AttrBuilder B;
+ B.addAttribute(Attributes::ReadOnly)
+ .addAttribute(Attributes::ReadNone);
+ F.removeAttribute(AttrListPtr::FunctionIndex,
+ Attributes::get(F.getContext(), B));
+
+ return Visitor.runOnFunction();
+}
Propchange: llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp
------------------------------------------------------------------------------
svn:eol-style = LF
Added: llvm/trunk/test/Instrumentation/MemorySanitizer/lit.local.cfg
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Instrumentation/MemorySanitizer/lit.local.cfg?rev=168866&view=auto
==============================================================================
--- llvm/trunk/test/Instrumentation/MemorySanitizer/lit.local.cfg (added)
+++ llvm/trunk/test/Instrumentation/MemorySanitizer/lit.local.cfg Thu Nov 29 03:57:20 2012
@@ -0,0 +1 @@
+config.suffixes = ['.ll', '.c', '.cpp']
Added: llvm/trunk/test/Instrumentation/MemorySanitizer/msan_basic.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Instrumentation/MemorySanitizer/msan_basic.ll?rev=168866&view=auto
==============================================================================
--- llvm/trunk/test/Instrumentation/MemorySanitizer/msan_basic.ll (added)
+++ llvm/trunk/test/Instrumentation/MemorySanitizer/msan_basic.ll Thu Nov 29 03:57:20 2012
@@ -0,0 +1,235 @@
+; RUN: opt < %s -msan -S | FileCheck %s
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
+
+; Check the presence of __msan_init
+; CHECK: @llvm.global_ctors {{.*}} @__msan_init
+
+; load followed by cmp: check that we load the shadow and call __msan_warning.
+define void @LoadAndCmp(i32* nocapture %a) nounwind uwtable {
+entry:
+ %0 = load i32* %a, align 4
+ %tobool = icmp eq i32 %0, 0
+ br i1 %tobool, label %if.end, label %if.then
+
+if.then: ; preds = %entry
+ tail call void (...)* @foo() nounwind
+ br label %if.end
+
+if.end: ; preds = %entry, %if.then
+ ret void
+}
+
+declare void @foo(...)
+
+; CHECK: define void @LoadAndCmp
+; CHECK: = load
+; CHECK: = load
+; CHECK: call void @__msan_warning_noreturn()
+; CHECK: }
+
+; Check that we store the shadow for the retval.
+define i32 @ReturnInt() nounwind uwtable readnone {
+entry:
+ ret i32 123
+}
+
+; CHECK: define i32 @ReturnInt()
+; CHECK: store i32 0,{{.*}}__msan_retval_tls
+; CHECK: }
+
+; Check that we get the shadow for the retval.
+define void @CopyRetVal(i32* nocapture %a) nounwind uwtable {
+entry:
+ %call = tail call i32 @ReturnInt() nounwind
+ store i32 %call, i32* %a, align 4
+ ret void
+}
+
+; CHECK: define void @CopyRetVal
+; CHECK: load{{.*}}__msan_retval_tls
+; CHECK: store
+; CHECK: store
+; CHECK: }
+
+
+; Check that we generate PHIs for shadow.
+define void @FuncWithPhi(i32* nocapture %a, i32* %b, i32* nocapture %c) nounwind uwtable {
+entry:
+ %tobool = icmp eq i32* %b, null
+ br i1 %tobool, label %if.else, label %if.then
+
+ if.then: ; preds = %entry
+ %0 = load i32* %b, align 4
+ br label %if.end
+
+ if.else: ; preds = %entry
+ %1 = load i32* %c, align 4
+ br label %if.end
+
+ if.end: ; preds = %if.else, %if.then
+ %t.0 = phi i32 [ %0, %if.then ], [ %1, %if.else ]
+ store i32 %t.0, i32* %a, align 4
+ ret void
+}
+
+; CHECK: define void @FuncWithPhi
+; CHECK: = phi
+; CHECK-NEXT: = phi
+; CHECK: store
+; CHECK: store
+; CHECK: }
+
+; Compute shadow for "x << 10"
+define void @ShlConst(i32* nocapture %x) nounwind uwtable {
+entry:
+ %0 = load i32* %x, align 4
+ %1 = shl i32 %0, 10
+ store i32 %1, i32* %x, align 4
+ ret void
+}
+
+; CHECK: define void @ShlConst
+; CHECK: = load
+; CHECK: = load
+; CHECK: shl
+; CHECK: shl
+; CHECK: store
+; CHECK: store
+; CHECK: }
+
+; Compute shadow for "10 << x": it should have 'sext i1'.
+define void @ShlNonConst(i32* nocapture %x) nounwind uwtable {
+entry:
+ %0 = load i32* %x, align 4
+ %1 = shl i32 10, %0
+ store i32 %1, i32* %x, align 4
+ ret void
+}
+
+; CHECK: define void @ShlNonConst
+; CHECK: = load
+; CHECK: = load
+; CHECK: = sext i1
+; CHECK: store
+; CHECK: store
+; CHECK: }
+
+; SExt
+define void @SExt(i32* nocapture %a, i16* nocapture %b) nounwind uwtable {
+entry:
+ %0 = load i16* %b, align 2
+ %1 = sext i16 %0 to i32
+ store i32 %1, i32* %a, align 4
+ ret void
+}
+
+; CHECK: define void @SExt
+; CHECK: = load
+; CHECK: = load
+; CHECK: = sext
+; CHECK: = sext
+; CHECK: store
+; CHECK: store
+; CHECK: }
+
+
+; memset
+define void @MemSet(i8* nocapture %x) nounwind uwtable {
+entry:
+ call void @llvm.memset.p0i8.i64(i8* %x, i8 42, i64 10, i32 1, i1 false)
+ ret void
+}
+
+declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i32, i1) nounwind
+
+; CHECK: define void @MemSet
+; CHECK: call void @llvm.memset.p0i8.i64
+; CHECK: call void @llvm.memset.p0i8.i64
+; CHECK: }
+
+
+; memcpy
+define void @MemCpy(i8* nocapture %x, i8* nocapture %y) nounwind uwtable {
+entry:
+ call void @llvm.memcpy.p0i8.p0i8.i64(i8* %x, i8* %y, i64 10, i32 1, i1 false)
+ ret void
+}
+
+declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture, i64, i32, i1) nounwind
+
+; CHECK: define void @MemCpy
+; CHECK: call void @llvm.memcpy.p0i8.p0i8.i64
+; CHECK: call void @llvm.memcpy.p0i8.p0i8.i64
+; CHECK: }
+
+
+; memmove is lowered to a call
+define void @MemMove(i8* nocapture %x, i8* nocapture %y) nounwind uwtable {
+entry:
+ call void @llvm.memmove.p0i8.p0i8.i64(i8* %x, i8* %y, i64 10, i32 1, i1 false)
+ ret void
+}
+
+declare void @llvm.memmove.p0i8.p0i8.i64(i8* nocapture, i8* nocapture, i64, i32, i1) nounwind
+
+; CHECK: define void @MemMove
+; CHECK: call i8* @memmove
+; CHECK: }
+
+
+; Check that we propagate shadow for "select"
+
+define i32 @Select(i32 %a, i32 %b, i32 %c) nounwind uwtable readnone {
+entry:
+ %tobool = icmp ne i32 %c, 0
+ %cond = select i1 %tobool, i32 %a, i32 %b
+ ret i32 %cond
+}
+
+; CHECK: define i32 @Select
+; CHECK: select
+; CHECK-NEXT: select
+; CHECK: }
+
+
+define i8* @IntToPtr(i64 %x) nounwind uwtable readnone {
+entry:
+ %0 = inttoptr i64 %x to i8*
+ ret i8* %0
+}
+
+; CHECK: define i8* @IntToPtr
+; CHECK: load i64*{{.*}}__msan_param_tls
+; CHECK-NEXT: inttoptr
+; CHECK-NEXT: store i64{{.*}}__msan_retval_tls
+; CHECK: }
+
+
+define i8* @IntToPtr_ZExt(i16 %x) nounwind uwtable readnone {
+entry:
+ %0 = inttoptr i16 %x to i8*
+ ret i8* %0
+}
+
+; CHECK: define i8* @IntToPtr_ZExt
+; CHECK: zext
+; CHECK-NEXT: inttoptr
+; CHECK: }
+
+
+; Check that we insert exactly one check on udiv
+; (2nd arg shadow is checked, 1st arg shadow is propagated)
+
+define i32 @Div(i32 %a, i32 %b) nounwind uwtable readnone {
+entry:
+ %div = udiv i32 %a, %b
+ ret i32 %div
+}
+
+; CHECK: define i32 @Div
+; CHECK: icmp
+; CHECK: br
+; CHECK-NOT: icmp
+; CHECK: udiv
+; CHECK-NOT: icmp
+; CHECK: }
More information about the llvm-commits
mailing list