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-rw-r--r--lib/Analysis/Lint.cpp560
1 files changed, 375 insertions, 185 deletions
diff --git a/lib/Analysis/Lint.cpp b/lib/Analysis/Lint.cpp
index b5c7245030fc..65a90d7bcd87 100644
--- a/lib/Analysis/Lint.cpp
+++ b/lib/Analysis/Lint.cpp
@@ -36,12 +36,14 @@
#include "llvm/Analysis/Lint.h"
#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallSet.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/AssumptionCache.h"
#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/Loads.h"
#include "llvm/Analysis/Passes.h"
+#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/DataLayout.h"
@@ -49,19 +51,18 @@
#include "llvm/IR/Function.h"
#include "llvm/IR/InstVisitor.h"
#include "llvm/IR/IntrinsicInst.h"
+#include "llvm/IR/LegacyPassManager.h"
#include "llvm/Pass.h"
-#include "llvm/PassManager.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
-#include "llvm/Target/TargetLibraryInfo.h"
using namespace llvm;
namespace {
namespace MemRef {
- static unsigned Read = 1;
- static unsigned Write = 2;
- static unsigned Callee = 4;
- static unsigned Branchee = 8;
+ static const unsigned Read = 1;
+ static const unsigned Write = 2;
+ static const unsigned Callee = 4;
+ static const unsigned Branchee = 8;
}
class Lint : public FunctionPass, public InstVisitor<Lint> {
@@ -73,6 +74,8 @@ namespace {
void visitMemoryReference(Instruction &I, Value *Ptr,
uint64_t Size, unsigned Align,
Type *Ty, unsigned Flags);
+ void visitEHBeginCatch(IntrinsicInst *II);
+ void visitEHEndCatch(IntrinsicInst *II);
void visitCallInst(CallInst &I);
void visitInvokeInst(InvokeInst &I);
@@ -95,8 +98,8 @@ namespace {
void visitInsertElementInst(InsertElementInst &I);
void visitUnreachableInst(UnreachableInst &I);
- Value *findValue(Value *V, bool OffsetOk) const;
- Value *findValueImpl(Value *V, bool OffsetOk,
+ Value *findValue(Value *V, const DataLayout &DL, bool OffsetOk) const;
+ Value *findValueImpl(Value *V, const DataLayout &DL, bool OffsetOk,
SmallPtrSetImpl<Value *> &Visited) const;
public:
@@ -104,7 +107,6 @@ namespace {
AliasAnalysis *AA;
AssumptionCache *AC;
DominatorTree *DT;
- const DataLayout *DL;
TargetLibraryInfo *TLI;
std::string Messages;
@@ -121,32 +123,38 @@ namespace {
AU.setPreservesAll();
AU.addRequired<AliasAnalysis>();
AU.addRequired<AssumptionCacheTracker>();
- AU.addRequired<TargetLibraryInfo>();
+ AU.addRequired<TargetLibraryInfoWrapperPass>();
AU.addRequired<DominatorTreeWrapperPass>();
}
void print(raw_ostream &O, const Module *M) const override {}
- void WriteValue(const Value *V) {
- if (!V) return;
- if (isa<Instruction>(V)) {
- MessagesStr << *V << '\n';
- } else {
- V->printAsOperand(MessagesStr, true, Mod);
- MessagesStr << '\n';
+ void WriteValues(ArrayRef<const Value *> Vs) {
+ for (const Value *V : Vs) {
+ if (!V)
+ continue;
+ if (isa<Instruction>(V)) {
+ MessagesStr << *V << '\n';
+ } else {
+ V->printAsOperand(MessagesStr, true, Mod);
+ MessagesStr << '\n';
+ }
}
}
- // CheckFailed - A check failed, so print out the condition and the message
- // that failed. This provides a nice place to put a breakpoint if you want
- // to see why something is not correct.
- void CheckFailed(const Twine &Message,
- const Value *V1 = nullptr, const Value *V2 = nullptr,
- const Value *V3 = nullptr, const Value *V4 = nullptr) {
- MessagesStr << Message.str() << "\n";
- WriteValue(V1);
- WriteValue(V2);
- WriteValue(V3);
- WriteValue(V4);
+ /// \brief A check failed, so printout out the condition and the message.
+ ///
+ /// This provides a nice place to put a breakpoint if you want to see why
+ /// something is not correct.
+ void CheckFailed(const Twine &Message) { MessagesStr << Message << '\n'; }
+
+ /// \brief A check failed (with values to print).
+ ///
+ /// This calls the Message-only version so that the above is easier to set
+ /// a breakpoint on.
+ template <typename T1, typename... Ts>
+ void CheckFailed(const Twine &Message, const T1 &V1, const Ts &...Vs) {
+ CheckFailed(Message);
+ WriteValues({V1, Vs...});
}
};
}
@@ -155,23 +163,15 @@ char Lint::ID = 0;
INITIALIZE_PASS_BEGIN(Lint, "lint", "Statically lint-checks LLVM IR",
false, true)
INITIALIZE_PASS_DEPENDENCY(AssumptionCacheTracker)
-INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfo)
+INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass)
INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
INITIALIZE_AG_DEPENDENCY(AliasAnalysis)
INITIALIZE_PASS_END(Lint, "lint", "Statically lint-checks LLVM IR",
false, true)
// Assert - We know that cond should be true, if not print an error message.
-#define Assert(C, M) \
- do { if (!(C)) { CheckFailed(M); return; } } while (0)
-#define Assert1(C, M, V1) \
- do { if (!(C)) { CheckFailed(M, V1); return; } } while (0)
-#define Assert2(C, M, V1, V2) \
- do { if (!(C)) { CheckFailed(M, V1, V2); return; } } while (0)
-#define Assert3(C, M, V1, V2, V3) \
- do { if (!(C)) { CheckFailed(M, V1, V2, V3); return; } } while (0)
-#define Assert4(C, M, V1, V2, V3, V4) \
- do { if (!(C)) { CheckFailed(M, V1, V2, V3, V4); return; } } while (0)
+#define Assert(C, ...) \
+ do { if (!(C)) { CheckFailed(__VA_ARGS__); return; } } while (0)
// Lint::run - This is the main Analysis entry point for a
// function.
@@ -181,9 +181,7 @@ bool Lint::runOnFunction(Function &F) {
AA = &getAnalysis<AliasAnalysis>();
AC = &getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F);
DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
- DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>();
- DL = DLP ? &DLP->getDataLayout() : nullptr;
- TLI = &getAnalysis<TargetLibraryInfo>();
+ TLI = &getAnalysis<TargetLibraryInfoWrapperPass>().getTLI();
visit(F);
dbgs() << MessagesStr.str();
Messages.clear();
@@ -193,8 +191,8 @@ bool Lint::runOnFunction(Function &F) {
void Lint::visitFunction(Function &F) {
// This isn't undefined behavior, it's just a little unusual, and it's a
// fairly common mistake to neglect to name a function.
- Assert1(F.hasName() || F.hasLocalLinkage(),
- "Unusual: Unnamed function with non-local linkage", &F);
+ Assert(F.hasName() || F.hasLocalLinkage(),
+ "Unusual: Unnamed function with non-local linkage", &F);
// TODO: Check for irreducible control flow.
}
@@ -202,27 +200,30 @@ void Lint::visitFunction(Function &F) {
void Lint::visitCallSite(CallSite CS) {
Instruction &I = *CS.getInstruction();
Value *Callee = CS.getCalledValue();
+ const DataLayout &DL = CS->getModule()->getDataLayout();
visitMemoryReference(I, Callee, AliasAnalysis::UnknownSize,
0, nullptr, MemRef::Callee);
- if (Function *F = dyn_cast<Function>(findValue(Callee, /*OffsetOk=*/false))) {
- Assert1(CS.getCallingConv() == F->getCallingConv(),
- "Undefined behavior: Caller and callee calling convention differ",
- &I);
+ if (Function *F = dyn_cast<Function>(findValue(Callee, DL,
+ /*OffsetOk=*/false))) {
+ Assert(CS.getCallingConv() == F->getCallingConv(),
+ "Undefined behavior: Caller and callee calling convention differ",
+ &I);
FunctionType *FT = F->getFunctionType();
unsigned NumActualArgs = CS.arg_size();
- Assert1(FT->isVarArg() ?
- FT->getNumParams() <= NumActualArgs :
- FT->getNumParams() == NumActualArgs,
- "Undefined behavior: Call argument count mismatches callee "
- "argument count", &I);
+ Assert(FT->isVarArg() ? FT->getNumParams() <= NumActualArgs
+ : FT->getNumParams() == NumActualArgs,
+ "Undefined behavior: Call argument count mismatches callee "
+ "argument count",
+ &I);
- Assert1(FT->getReturnType() == I.getType(),
- "Undefined behavior: Call return type mismatches "
- "callee return type", &I);
+ Assert(FT->getReturnType() == I.getType(),
+ "Undefined behavior: Call return type mismatches "
+ "callee return type",
+ &I);
// Check argument types (in case the callee was casted) and attributes.
// TODO: Verify that caller and callee attributes are compatible.
@@ -232,9 +233,10 @@ void Lint::visitCallSite(CallSite CS) {
Value *Actual = *AI;
if (PI != PE) {
Argument *Formal = PI++;
- Assert1(Formal->getType() == Actual->getType(),
- "Undefined behavior: Call argument type mismatches "
- "callee parameter type", &I);
+ Assert(Formal->getType() == Actual->getType(),
+ "Undefined behavior: Call argument type mismatches "
+ "callee parameter type",
+ &I);
// Check that noalias arguments don't alias other arguments. This is
// not fully precise because we don't know the sizes of the dereferenced
@@ -243,9 +245,9 @@ void Lint::visitCallSite(CallSite CS) {
for (CallSite::arg_iterator BI = CS.arg_begin(); BI != AE; ++BI)
if (AI != BI && (*BI)->getType()->isPointerTy()) {
AliasAnalysis::AliasResult Result = AA->alias(*AI, *BI);
- Assert1(Result != AliasAnalysis::MustAlias &&
- Result != AliasAnalysis::PartialAlias,
- "Unusual: noalias argument aliases another argument", &I);
+ Assert(Result != AliasAnalysis::MustAlias &&
+ Result != AliasAnalysis::PartialAlias,
+ "Unusual: noalias argument aliases another argument", &I);
}
// Check that an sret argument points to valid memory.
@@ -253,8 +255,8 @@ void Lint::visitCallSite(CallSite CS) {
Type *Ty =
cast<PointerType>(Formal->getType())->getElementType();
visitMemoryReference(I, Actual, AA->getTypeStoreSize(Ty),
- DL ? DL->getABITypeAlignment(Ty) : 0,
- Ty, MemRef::Read | MemRef::Write);
+ DL.getABITypeAlignment(Ty), Ty,
+ MemRef::Read | MemRef::Write);
}
}
}
@@ -263,10 +265,11 @@ void Lint::visitCallSite(CallSite CS) {
if (CS.isCall() && cast<CallInst>(CS.getInstruction())->isTailCall())
for (CallSite::arg_iterator AI = CS.arg_begin(), AE = CS.arg_end();
AI != AE; ++AI) {
- Value *Obj = findValue(*AI, /*OffsetOk=*/true);
- Assert1(!isa<AllocaInst>(Obj),
- "Undefined behavior: Call with \"tail\" keyword references "
- "alloca", &I);
+ Value *Obj = findValue(*AI, DL, /*OffsetOk=*/true);
+ Assert(!isa<AllocaInst>(Obj),
+ "Undefined behavior: Call with \"tail\" keyword references "
+ "alloca",
+ &I);
}
@@ -291,13 +294,13 @@ void Lint::visitCallSite(CallSite CS) {
// overlap is not distinguished from the case where nothing is known.
uint64_t Size = 0;
if (const ConstantInt *Len =
- dyn_cast<ConstantInt>(findValue(MCI->getLength(),
- /*OffsetOk=*/false)))
+ dyn_cast<ConstantInt>(findValue(MCI->getLength(), DL,
+ /*OffsetOk=*/false)))
if (Len->getValue().isIntN(32))
Size = Len->getValue().getZExtValue();
- Assert1(AA->alias(MCI->getSource(), Size, MCI->getDest(), Size) !=
- AliasAnalysis::MustAlias,
- "Undefined behavior: memcpy source and destination overlap", &I);
+ Assert(AA->alias(MCI->getSource(), Size, MCI->getDest(), Size) !=
+ AliasAnalysis::MustAlias,
+ "Undefined behavior: memcpy source and destination overlap", &I);
break;
}
case Intrinsic::memmove: {
@@ -321,9 +324,9 @@ void Lint::visitCallSite(CallSite CS) {
}
case Intrinsic::vastart:
- Assert1(I.getParent()->getParent()->isVarArg(),
- "Undefined behavior: va_start called in a non-varargs function",
- &I);
+ Assert(I.getParent()->getParent()->isVarArg(),
+ "Undefined behavior: va_start called in a non-varargs function",
+ &I);
visitMemoryReference(I, CS.getArgument(0), AliasAnalysis::UnknownSize,
0, nullptr, MemRef::Read | MemRef::Write);
@@ -346,6 +349,13 @@ void Lint::visitCallSite(CallSite CS) {
visitMemoryReference(I, CS.getArgument(0), AliasAnalysis::UnknownSize,
0, nullptr, MemRef::Read | MemRef::Write);
break;
+
+ case Intrinsic::eh_begincatch:
+ visitEHBeginCatch(II);
+ break;
+ case Intrinsic::eh_endcatch:
+ visitEHEndCatch(II);
+ break;
}
}
@@ -359,14 +369,13 @@ void Lint::visitInvokeInst(InvokeInst &I) {
void Lint::visitReturnInst(ReturnInst &I) {
Function *F = I.getParent()->getParent();
- Assert1(!F->doesNotReturn(),
- "Unusual: Return statement in function with noreturn attribute",
- &I);
+ Assert(!F->doesNotReturn(),
+ "Unusual: Return statement in function with noreturn attribute", &I);
if (Value *V = I.getReturnValue()) {
- Value *Obj = findValue(V, /*OffsetOk=*/true);
- Assert1(!isa<AllocaInst>(Obj),
- "Unusual: Returning alloca value", &I);
+ Value *Obj =
+ findValue(V, F->getParent()->getDataLayout(), /*OffsetOk=*/true);
+ Assert(!isa<AllocaInst>(Obj), "Unusual: Returning alloca value", &I);
}
}
@@ -380,45 +389,47 @@ void Lint::visitMemoryReference(Instruction &I,
if (Size == 0)
return;
- Value *UnderlyingObject = findValue(Ptr, /*OffsetOk=*/true);
- Assert1(!isa<ConstantPointerNull>(UnderlyingObject),
- "Undefined behavior: Null pointer dereference", &I);
- Assert1(!isa<UndefValue>(UnderlyingObject),
- "Undefined behavior: Undef pointer dereference", &I);
- Assert1(!isa<ConstantInt>(UnderlyingObject) ||
- !cast<ConstantInt>(UnderlyingObject)->isAllOnesValue(),
- "Unusual: All-ones pointer dereference", &I);
- Assert1(!isa<ConstantInt>(UnderlyingObject) ||
- !cast<ConstantInt>(UnderlyingObject)->isOne(),
- "Unusual: Address one pointer dereference", &I);
+ Value *UnderlyingObject =
+ findValue(Ptr, I.getModule()->getDataLayout(), /*OffsetOk=*/true);
+ Assert(!isa<ConstantPointerNull>(UnderlyingObject),
+ "Undefined behavior: Null pointer dereference", &I);
+ Assert(!isa<UndefValue>(UnderlyingObject),
+ "Undefined behavior: Undef pointer dereference", &I);
+ Assert(!isa<ConstantInt>(UnderlyingObject) ||
+ !cast<ConstantInt>(UnderlyingObject)->isAllOnesValue(),
+ "Unusual: All-ones pointer dereference", &I);
+ Assert(!isa<ConstantInt>(UnderlyingObject) ||
+ !cast<ConstantInt>(UnderlyingObject)->isOne(),
+ "Unusual: Address one pointer dereference", &I);
if (Flags & MemRef::Write) {
if (const GlobalVariable *GV = dyn_cast<GlobalVariable>(UnderlyingObject))
- Assert1(!GV->isConstant(),
- "Undefined behavior: Write to read-only memory", &I);
- Assert1(!isa<Function>(UnderlyingObject) &&
- !isa<BlockAddress>(UnderlyingObject),
- "Undefined behavior: Write to text section", &I);
+ Assert(!GV->isConstant(), "Undefined behavior: Write to read-only memory",
+ &I);
+ Assert(!isa<Function>(UnderlyingObject) &&
+ !isa<BlockAddress>(UnderlyingObject),
+ "Undefined behavior: Write to text section", &I);
}
if (Flags & MemRef::Read) {
- Assert1(!isa<Function>(UnderlyingObject),
- "Unusual: Load from function body", &I);
- Assert1(!isa<BlockAddress>(UnderlyingObject),
- "Undefined behavior: Load from block address", &I);
+ Assert(!isa<Function>(UnderlyingObject), "Unusual: Load from function body",
+ &I);
+ Assert(!isa<BlockAddress>(UnderlyingObject),
+ "Undefined behavior: Load from block address", &I);
}
if (Flags & MemRef::Callee) {
- Assert1(!isa<BlockAddress>(UnderlyingObject),
- "Undefined behavior: Call to block address", &I);
+ Assert(!isa<BlockAddress>(UnderlyingObject),
+ "Undefined behavior: Call to block address", &I);
}
if (Flags & MemRef::Branchee) {
- Assert1(!isa<Constant>(UnderlyingObject) ||
- isa<BlockAddress>(UnderlyingObject),
- "Undefined behavior: Branch to non-blockaddress", &I);
+ Assert(!isa<Constant>(UnderlyingObject) ||
+ isa<BlockAddress>(UnderlyingObject),
+ "Undefined behavior: Branch to non-blockaddress", &I);
}
// Check for buffer overflows and misalignment.
// Only handles memory references that read/write something simple like an
// alloca instruction or a global variable.
+ auto &DL = I.getModule()->getDataLayout();
int64_t Offset = 0;
if (Value *Base = GetPointerBaseWithConstantOffset(Ptr, Offset, DL)) {
// OK, so the access is to a constant offset from Ptr. Check that Ptr is
@@ -429,37 +440,37 @@ void Lint::visitMemoryReference(Instruction &I,
if (AllocaInst *AI = dyn_cast<AllocaInst>(Base)) {
Type *ATy = AI->getAllocatedType();
- if (DL && !AI->isArrayAllocation() && ATy->isSized())
- BaseSize = DL->getTypeAllocSize(ATy);
+ if (!AI->isArrayAllocation() && ATy->isSized())
+ BaseSize = DL.getTypeAllocSize(ATy);
BaseAlign = AI->getAlignment();
- if (DL && BaseAlign == 0 && ATy->isSized())
- BaseAlign = DL->getABITypeAlignment(ATy);
+ if (BaseAlign == 0 && ATy->isSized())
+ BaseAlign = DL.getABITypeAlignment(ATy);
} else if (GlobalVariable *GV = dyn_cast<GlobalVariable>(Base)) {
// If the global may be defined differently in another compilation unit
// then don't warn about funky memory accesses.
if (GV->hasDefinitiveInitializer()) {
Type *GTy = GV->getType()->getElementType();
- if (DL && GTy->isSized())
- BaseSize = DL->getTypeAllocSize(GTy);
+ if (GTy->isSized())
+ BaseSize = DL.getTypeAllocSize(GTy);
BaseAlign = GV->getAlignment();
- if (DL && BaseAlign == 0 && GTy->isSized())
- BaseAlign = DL->getABITypeAlignment(GTy);
+ if (BaseAlign == 0 && GTy->isSized())
+ BaseAlign = DL.getABITypeAlignment(GTy);
}
}
// Accesses from before the start or after the end of the object are not
// defined.
- Assert1(Size == AliasAnalysis::UnknownSize ||
- BaseSize == AliasAnalysis::UnknownSize ||
- (Offset >= 0 && Offset + Size <= BaseSize),
- "Undefined behavior: Buffer overflow", &I);
+ Assert(Size == AliasAnalysis::UnknownSize ||
+ BaseSize == AliasAnalysis::UnknownSize ||
+ (Offset >= 0 && Offset + Size <= BaseSize),
+ "Undefined behavior: Buffer overflow", &I);
// Accesses that say that the memory is more aligned than it is are not
// defined.
- if (DL && Align == 0 && Ty && Ty->isSized())
- Align = DL->getABITypeAlignment(Ty);
- Assert1(!BaseAlign || Align <= MinAlign(BaseAlign, Offset),
- "Undefined behavior: Memory reference address is misaligned", &I);
+ if (Align == 0 && Ty && Ty->isSized())
+ Align = DL.getABITypeAlignment(Ty);
+ Assert(!BaseAlign || Align <= MinAlign(BaseAlign, Offset),
+ "Undefined behavior: Memory reference address is misaligned", &I);
}
}
@@ -477,39 +488,219 @@ void Lint::visitStoreInst(StoreInst &I) {
}
void Lint::visitXor(BinaryOperator &I) {
- Assert1(!isa<UndefValue>(I.getOperand(0)) ||
- !isa<UndefValue>(I.getOperand(1)),
- "Undefined result: xor(undef, undef)", &I);
+ Assert(!isa<UndefValue>(I.getOperand(0)) || !isa<UndefValue>(I.getOperand(1)),
+ "Undefined result: xor(undef, undef)", &I);
}
void Lint::visitSub(BinaryOperator &I) {
- Assert1(!isa<UndefValue>(I.getOperand(0)) ||
- !isa<UndefValue>(I.getOperand(1)),
- "Undefined result: sub(undef, undef)", &I);
+ Assert(!isa<UndefValue>(I.getOperand(0)) || !isa<UndefValue>(I.getOperand(1)),
+ "Undefined result: sub(undef, undef)", &I);
}
void Lint::visitLShr(BinaryOperator &I) {
- if (ConstantInt *CI =
- dyn_cast<ConstantInt>(findValue(I.getOperand(1), /*OffsetOk=*/false)))
- Assert1(CI->getValue().ult(cast<IntegerType>(I.getType())->getBitWidth()),
- "Undefined result: Shift count out of range", &I);
+ if (ConstantInt *CI = dyn_cast<ConstantInt>(
+ findValue(I.getOperand(1), I.getModule()->getDataLayout(),
+ /*OffsetOk=*/false)))
+ Assert(CI->getValue().ult(cast<IntegerType>(I.getType())->getBitWidth()),
+ "Undefined result: Shift count out of range", &I);
}
void Lint::visitAShr(BinaryOperator &I) {
- if (ConstantInt *CI =
- dyn_cast<ConstantInt>(findValue(I.getOperand(1), /*OffsetOk=*/false)))
- Assert1(CI->getValue().ult(cast<IntegerType>(I.getType())->getBitWidth()),
- "Undefined result: Shift count out of range", &I);
+ if (ConstantInt *CI = dyn_cast<ConstantInt>(findValue(
+ I.getOperand(1), I.getModule()->getDataLayout(), /*OffsetOk=*/false)))
+ Assert(CI->getValue().ult(cast<IntegerType>(I.getType())->getBitWidth()),
+ "Undefined result: Shift count out of range", &I);
}
void Lint::visitShl(BinaryOperator &I) {
- if (ConstantInt *CI =
- dyn_cast<ConstantInt>(findValue(I.getOperand(1), /*OffsetOk=*/false)))
- Assert1(CI->getValue().ult(cast<IntegerType>(I.getType())->getBitWidth()),
- "Undefined result: Shift count out of range", &I);
+ if (ConstantInt *CI = dyn_cast<ConstantInt>(findValue(
+ I.getOperand(1), I.getModule()->getDataLayout(), /*OffsetOk=*/false)))
+ Assert(CI->getValue().ult(cast<IntegerType>(I.getType())->getBitWidth()),
+ "Undefined result: Shift count out of range", &I);
+}
+
+static bool
+allPredsCameFromLandingPad(BasicBlock *BB,
+ SmallSet<BasicBlock *, 4> &VisitedBlocks) {
+ VisitedBlocks.insert(BB);
+ if (BB->isLandingPad())
+ return true;
+ // If we find a block with no predecessors, the search failed.
+ if (pred_empty(BB))
+ return false;
+ for (BasicBlock *Pred : predecessors(BB)) {
+ if (VisitedBlocks.count(Pred))
+ continue;
+ if (!allPredsCameFromLandingPad(Pred, VisitedBlocks))
+ return false;
+ }
+ return true;
+}
+
+static bool
+allSuccessorsReachEndCatch(BasicBlock *BB, BasicBlock::iterator InstBegin,
+ IntrinsicInst **SecondBeginCatch,
+ SmallSet<BasicBlock *, 4> &VisitedBlocks) {
+ VisitedBlocks.insert(BB);
+ for (BasicBlock::iterator I = InstBegin, E = BB->end(); I != E; ++I) {
+ IntrinsicInst *IC = dyn_cast<IntrinsicInst>(I);
+ if (IC && IC->getIntrinsicID() == Intrinsic::eh_endcatch)
+ return true;
+ // If we find another begincatch while looking for an endcatch,
+ // that's also an error.
+ if (IC && IC->getIntrinsicID() == Intrinsic::eh_begincatch) {
+ *SecondBeginCatch = IC;
+ return false;
+ }
+ }
+
+ // If we reach a block with no successors while searching, the
+ // search has failed.
+ if (succ_empty(BB))
+ return false;
+ // Otherwise, search all of the successors.
+ for (BasicBlock *Succ : successors(BB)) {
+ if (VisitedBlocks.count(Succ))
+ continue;
+ if (!allSuccessorsReachEndCatch(Succ, Succ->begin(), SecondBeginCatch,
+ VisitedBlocks))
+ return false;
+ }
+ return true;
+}
+
+void Lint::visitEHBeginCatch(IntrinsicInst *II) {
+ // The checks in this function make a potentially dubious assumption about
+ // the CFG, namely that any block involved in a catch is only used for the
+ // catch. This will very likely be true of IR generated by a front end,
+ // but it may cease to be true, for example, if the IR is run through a
+ // pass which combines similar blocks.
+ //
+ // In general, if we encounter a block the isn't dominated by the catch
+ // block while we are searching the catch block's successors for a call
+ // to end catch intrinsic, then it is possible that it will be legal for
+ // a path through this block to never reach a call to llvm.eh.endcatch.
+ // An analogous statement could be made about our search for a landing
+ // pad among the catch block's predecessors.
+ //
+ // What is actually required is that no path is possible at runtime that
+ // reaches a call to llvm.eh.begincatch without having previously visited
+ // a landingpad instruction and that no path is possible at runtime that
+ // calls llvm.eh.begincatch and does not subsequently call llvm.eh.endcatch
+ // (mentally adjusting for the fact that in reality these calls will be
+ // removed before code generation).
+ //
+ // Because this is a lint check, we take a pessimistic approach and warn if
+ // the control flow is potentially incorrect.
+
+ SmallSet<BasicBlock *, 4> VisitedBlocks;
+ BasicBlock *CatchBB = II->getParent();
+
+ // The begin catch must occur in a landing pad block or all paths
+ // to it must have come from a landing pad.
+ Assert(allPredsCameFromLandingPad(CatchBB, VisitedBlocks),
+ "llvm.eh.begincatch may be reachable without passing a landingpad",
+ II);
+
+ // Reset the visited block list.
+ VisitedBlocks.clear();
+
+ IntrinsicInst *SecondBeginCatch = nullptr;
+
+ // This has to be called before it is asserted. Otherwise, the first assert
+ // below can never be hit.
+ bool EndCatchFound = allSuccessorsReachEndCatch(
+ CatchBB, std::next(static_cast<BasicBlock::iterator>(II)),
+ &SecondBeginCatch, VisitedBlocks);
+ Assert(
+ SecondBeginCatch == nullptr,
+ "llvm.eh.begincatch may be called a second time before llvm.eh.endcatch",
+ II, SecondBeginCatch);
+ Assert(EndCatchFound,
+ "Some paths from llvm.eh.begincatch may not reach llvm.eh.endcatch",
+ II);
+}
+
+static bool allPredCameFromBeginCatch(
+ BasicBlock *BB, BasicBlock::reverse_iterator InstRbegin,
+ IntrinsicInst **SecondEndCatch, SmallSet<BasicBlock *, 4> &VisitedBlocks) {
+ VisitedBlocks.insert(BB);
+ // Look for a begincatch in this block.
+ for (BasicBlock::reverse_iterator RI = InstRbegin, RE = BB->rend(); RI != RE;
+ ++RI) {
+ IntrinsicInst *IC = dyn_cast<IntrinsicInst>(&*RI);
+ if (IC && IC->getIntrinsicID() == Intrinsic::eh_begincatch)
+ return true;
+ // If we find another end catch before we find a begin catch, that's
+ // an error.
+ if (IC && IC->getIntrinsicID() == Intrinsic::eh_endcatch) {
+ *SecondEndCatch = IC;
+ return false;
+ }
+ // If we encounter a landingpad instruction, the search failed.
+ if (isa<LandingPadInst>(*RI))
+ return false;
+ }
+ // If while searching we find a block with no predeccesors,
+ // the search failed.
+ if (pred_empty(BB))
+ return false;
+ // Search any predecessors we haven't seen before.
+ for (BasicBlock *Pred : predecessors(BB)) {
+ if (VisitedBlocks.count(Pred))
+ continue;
+ if (!allPredCameFromBeginCatch(Pred, Pred->rbegin(), SecondEndCatch,
+ VisitedBlocks))
+ return false;
+ }
+ return true;
+}
+
+void Lint::visitEHEndCatch(IntrinsicInst *II) {
+ // The check in this function makes a potentially dubious assumption about
+ // the CFG, namely that any block involved in a catch is only used for the
+ // catch. This will very likely be true of IR generated by a front end,
+ // but it may cease to be true, for example, if the IR is run through a
+ // pass which combines similar blocks.
+ //
+ // In general, if we encounter a block the isn't post-dominated by the
+ // end catch block while we are searching the end catch block's predecessors
+ // for a call to the begin catch intrinsic, then it is possible that it will
+ // be legal for a path to reach the end catch block without ever having
+ // called llvm.eh.begincatch.
+ //
+ // What is actually required is that no path is possible at runtime that
+ // reaches a call to llvm.eh.endcatch without having previously visited
+ // a call to llvm.eh.begincatch (mentally adjusting for the fact that in
+ // reality these calls will be removed before code generation).
+ //
+ // Because this is a lint check, we take a pessimistic approach and warn if
+ // the control flow is potentially incorrect.
+
+ BasicBlock *EndCatchBB = II->getParent();
+
+ // Alls paths to the end catch call must pass through a begin catch call.
+
+ // If llvm.eh.begincatch wasn't called in the current block, we'll use this
+ // lambda to recursively look for it in predecessors.
+ SmallSet<BasicBlock *, 4> VisitedBlocks;
+ IntrinsicInst *SecondEndCatch = nullptr;
+
+ // This has to be called before it is asserted. Otherwise, the first assert
+ // below can never be hit.
+ bool BeginCatchFound =
+ allPredCameFromBeginCatch(EndCatchBB, BasicBlock::reverse_iterator(II),
+ &SecondEndCatch, VisitedBlocks);
+ Assert(
+ SecondEndCatch == nullptr,
+ "llvm.eh.endcatch may be called a second time after llvm.eh.begincatch",
+ II, SecondEndCatch);
+ Assert(BeginCatchFound,
+ "llvm.eh.endcatch may be reachable without passing llvm.eh.begincatch",
+ II);
}
-static bool isZero(Value *V, const DataLayout *DL, DominatorTree *DT,
+static bool isZero(Value *V, const DataLayout &DL, DominatorTree *DT,
AssumptionCache *AC) {
// Assume undef could be zero.
if (isa<UndefValue>(V))
@@ -550,30 +741,30 @@ static bool isZero(Value *V, const DataLayout *DL, DominatorTree *DT,
}
void Lint::visitSDiv(BinaryOperator &I) {
- Assert1(!isZero(I.getOperand(1), DL, DT, AC),
- "Undefined behavior: Division by zero", &I);
+ Assert(!isZero(I.getOperand(1), I.getModule()->getDataLayout(), DT, AC),
+ "Undefined behavior: Division by zero", &I);
}
void Lint::visitUDiv(BinaryOperator &I) {
- Assert1(!isZero(I.getOperand(1), DL, DT, AC),
- "Undefined behavior: Division by zero", &I);
+ Assert(!isZero(I.getOperand(1), I.getModule()->getDataLayout(), DT, AC),
+ "Undefined behavior: Division by zero", &I);
}
void Lint::visitSRem(BinaryOperator &I) {
- Assert1(!isZero(I.getOperand(1), DL, DT, AC),
- "Undefined behavior: Division by zero", &I);
+ Assert(!isZero(I.getOperand(1), I.getModule()->getDataLayout(), DT, AC),
+ "Undefined behavior: Division by zero", &I);
}
void Lint::visitURem(BinaryOperator &I) {
- Assert1(!isZero(I.getOperand(1), DL, DT, AC),
- "Undefined behavior: Division by zero", &I);
+ Assert(!isZero(I.getOperand(1), I.getModule()->getDataLayout(), DT, AC),
+ "Undefined behavior: Division by zero", &I);
}
void Lint::visitAllocaInst(AllocaInst &I) {
if (isa<ConstantInt>(I.getArraySize()))
// This isn't undefined behavior, it's just an obvious pessimization.
- Assert1(&I.getParent()->getParent()->getEntryBlock() == I.getParent(),
- "Pessimization: Static alloca outside of entry block", &I);
+ Assert(&I.getParent()->getParent()->getEntryBlock() == I.getParent(),
+ "Pessimization: Static alloca outside of entry block", &I);
// TODO: Check for an unusual size (MSB set?)
}
@@ -587,32 +778,33 @@ void Lint::visitIndirectBrInst(IndirectBrInst &I) {
visitMemoryReference(I, I.getAddress(), AliasAnalysis::UnknownSize, 0,
nullptr, MemRef::Branchee);
- Assert1(I.getNumDestinations() != 0,
- "Undefined behavior: indirectbr with no destinations", &I);
+ Assert(I.getNumDestinations() != 0,
+ "Undefined behavior: indirectbr with no destinations", &I);
}
void Lint::visitExtractElementInst(ExtractElementInst &I) {
- if (ConstantInt *CI =
- dyn_cast<ConstantInt>(findValue(I.getIndexOperand(),
- /*OffsetOk=*/false)))
- Assert1(CI->getValue().ult(I.getVectorOperandType()->getNumElements()),
- "Undefined result: extractelement index out of range", &I);
+ if (ConstantInt *CI = dyn_cast<ConstantInt>(
+ findValue(I.getIndexOperand(), I.getModule()->getDataLayout(),
+ /*OffsetOk=*/false)))
+ Assert(CI->getValue().ult(I.getVectorOperandType()->getNumElements()),
+ "Undefined result: extractelement index out of range", &I);
}
void Lint::visitInsertElementInst(InsertElementInst &I) {
- if (ConstantInt *CI =
- dyn_cast<ConstantInt>(findValue(I.getOperand(2),
- /*OffsetOk=*/false)))
- Assert1(CI->getValue().ult(I.getType()->getNumElements()),
- "Undefined result: insertelement index out of range", &I);
+ if (ConstantInt *CI = dyn_cast<ConstantInt>(
+ findValue(I.getOperand(2), I.getModule()->getDataLayout(),
+ /*OffsetOk=*/false)))
+ Assert(CI->getValue().ult(I.getType()->getNumElements()),
+ "Undefined result: insertelement index out of range", &I);
}
void Lint::visitUnreachableInst(UnreachableInst &I) {
// This isn't undefined behavior, it's merely suspicious.
- Assert1(&I == I.getParent()->begin() ||
- std::prev(BasicBlock::iterator(&I))->mayHaveSideEffects(),
- "Unusual: unreachable immediately preceded by instruction without "
- "side effects", &I);
+ Assert(&I == I.getParent()->begin() ||
+ std::prev(BasicBlock::iterator(&I))->mayHaveSideEffects(),
+ "Unusual: unreachable immediately preceded by instruction without "
+ "side effects",
+ &I);
}
/// findValue - Look through bitcasts and simple memory reference patterns
@@ -622,13 +814,13 @@ void Lint::visitUnreachableInst(UnreachableInst &I) {
/// Most analysis passes don't require this logic, because instcombine
/// will simplify most of these kinds of things away. But it's a goal of
/// this Lint pass to be useful even on non-optimized IR.
-Value *Lint::findValue(Value *V, bool OffsetOk) const {
+Value *Lint::findValue(Value *V, const DataLayout &DL, bool OffsetOk) const {
SmallPtrSet<Value *, 4> Visited;
- return findValueImpl(V, OffsetOk, Visited);
+ return findValueImpl(V, DL, OffsetOk, Visited);
}
/// findValueImpl - Implementation helper for findValue.
-Value *Lint::findValueImpl(Value *V, bool OffsetOk,
+Value *Lint::findValueImpl(Value *V, const DataLayout &DL, bool OffsetOk,
SmallPtrSetImpl<Value *> &Visited) const {
// Detect self-referential values.
if (!Visited.insert(V).second)
@@ -649,7 +841,7 @@ Value *Lint::findValueImpl(Value *V, bool OffsetOk,
break;
if (Value *U = FindAvailableLoadedValue(L->getPointerOperand(),
BB, BBI, 6, AA))
- return findValueImpl(U, OffsetOk, Visited);
+ return findValueImpl(U, DL, OffsetOk, Visited);
if (BBI != BB->begin()) break;
BB = BB->getUniquePredecessor();
if (!BB) break;
@@ -658,40 +850,38 @@ Value *Lint::findValueImpl(Value *V, bool OffsetOk,
} else if (PHINode *PN = dyn_cast<PHINode>(V)) {
if (Value *W = PN->hasConstantValue())
if (W != V)
- return findValueImpl(W, OffsetOk, Visited);
+ return findValueImpl(W, DL, OffsetOk, Visited);
} else if (CastInst *CI = dyn_cast<CastInst>(V)) {
if (CI->isNoopCast(DL))
- return findValueImpl(CI->getOperand(0), OffsetOk, Visited);
+ return findValueImpl(CI->getOperand(0), DL, OffsetOk, Visited);
} else if (ExtractValueInst *Ex = dyn_cast<ExtractValueInst>(V)) {
if (Value *W = FindInsertedValue(Ex->getAggregateOperand(),
Ex->getIndices()))
if (W != V)
- return findValueImpl(W, OffsetOk, Visited);
+ return findValueImpl(W, DL, OffsetOk, Visited);
} else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) {
// Same as above, but for ConstantExpr instead of Instruction.
if (Instruction::isCast(CE->getOpcode())) {
if (CastInst::isNoopCast(Instruction::CastOps(CE->getOpcode()),
- CE->getOperand(0)->getType(),
- CE->getType(),
- DL ? DL->getIntPtrType(V->getType()) :
- Type::getInt64Ty(V->getContext())))
- return findValueImpl(CE->getOperand(0), OffsetOk, Visited);
+ CE->getOperand(0)->getType(), CE->getType(),
+ DL.getIntPtrType(V->getType())))
+ return findValueImpl(CE->getOperand(0), DL, OffsetOk, Visited);
} else if (CE->getOpcode() == Instruction::ExtractValue) {
ArrayRef<unsigned> Indices = CE->getIndices();
if (Value *W = FindInsertedValue(CE->getOperand(0), Indices))
if (W != V)
- return findValueImpl(W, OffsetOk, Visited);
+ return findValueImpl(W, DL, OffsetOk, Visited);
}
}
// As a last resort, try SimplifyInstruction or constant folding.
if (Instruction *Inst = dyn_cast<Instruction>(V)) {
if (Value *W = SimplifyInstruction(Inst, DL, TLI, DT, AC))
- return findValueImpl(W, OffsetOk, Visited);
+ return findValueImpl(W, DL, OffsetOk, Visited);
} else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) {
if (Value *W = ConstantFoldConstantExpression(CE, DL, TLI))
if (W != V)
- return findValueImpl(W, OffsetOk, Visited);
+ return findValueImpl(W, DL, OffsetOk, Visited);
}
return V;
@@ -711,7 +901,7 @@ void llvm::lintFunction(const Function &f) {
Function &F = const_cast<Function&>(f);
assert(!F.isDeclaration() && "Cannot lint external functions");
- FunctionPassManager FPM(F.getParent());
+ legacy::FunctionPassManager FPM(F.getParent());
Lint *V = new Lint();
FPM.add(V);
FPM.run(F);
@@ -720,7 +910,7 @@ void llvm::lintFunction(const Function &f) {
/// lintModule - Check a module for errors, printing messages on stderr.
///
void llvm::lintModule(const Module &M) {
- PassManager PM;
+ legacy::PassManager PM;
Lint *V = new Lint();
PM.add(V);
PM.run(const_cast<Module&>(M));
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-31 14:28:42 +0000