DataLayout is mandatory, update the API to reflect it with references.

Summary:
Now that the DataLayout is a mandatory part of the module, let's start
cleaning the codebase. This patch is a first attempt at doing that.

This patch is not exactly NFC as for instance some places were passing
a nullptr instead of the DataLayout, possibly just because there was a
default value on the DataLayout argument to many functions in the API.
Even though it is not purely NFC, there is no change in the
validation.

I turned as many pointer to DataLayout to references, this helped
figuring out all the places where a nullptr could come up.

I had initially a local version of this patch broken into over 30
independant, commits but some later commit were cleaning the API and
touching part of the code modified in the previous commits, so it
seemed cleaner without the intermediate state.

Test Plan:

Reviewers: echristo

Subscribers: llvm-commits

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 231740

1 files changed, 58 insertions, 55 deletions

diff --git a/llvm/lib/Analysis/Lint.cpp b/llvm/lib/Analysis/Lint.cpp
index 56065db2814..887688737b0 100644
--- a/llvm/lib/Analysis/Lint.cpp
+++ b/llvm/lib/Analysis/Lint.cpp
@@ -98,8 +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:
@@ -107,7 +107,6 @@ namespace {
     AliasAnalysis *AA;
     AssumptionCache *AC;
     DominatorTree *DT;
-    const DataLayout *DL;
     TargetLibraryInfo *TLI;
 
     std::string Messages;
@@ -175,7 +174,6 @@ bool Lint::runOnFunction(Function &F) {
   AA = &getAnalysis<AliasAnalysis>();
   AC = &getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F);
   DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
-  DL = &F.getParent()->getDataLayout();
   TLI = &getAnalysis<TargetLibraryInfoWrapperPass>().getTLI();
   visit(F);
   dbgs() << MessagesStr.str();
@@ -195,11 +193,13 @@ 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))) {
+  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);
@@ -248,8 +248,8 @@ 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);
         }
       }
     }
@@ -258,9 +258,10 @@ 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);
+      Value *Obj = findValue(*AI, DL, /*OffsetOk=*/true);
       Assert(!isa<AllocaInst>(Obj),
-             "Undefined behavior: Call with \"tail\" keyword references alloca",
+             "Undefined behavior: Call with \"tail\" keyword references "
+             "alloca",
              &I);
     }
 
@@ -286,8 +287,8 @@ 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();
       Assert(AA->alias(MCI->getSource(), Size, MCI->getDest(), Size) !=
@@ -365,7 +366,8 @@ void Lint::visitReturnInst(ReturnInst &I) {
          "Unusual: Return statement in function with noreturn attribute", &I);
 
   if (Value *V = I.getReturnValue()) {
-    Value *Obj = findValue(V, /*OffsetOk=*/true);
+    Value *Obj =
+        findValue(V, F->getParent()->getDataLayout(), /*OffsetOk=*/true);
     Assert(!isa<AllocaInst>(Obj), "Unusual: Returning alloca value", &I);
   }
 }
@@ -380,7 +382,8 @@ void Lint::visitMemoryReference(Instruction &I,
   if (Size == 0)
     return;
 
-  Value *UnderlyingObject = findValue(Ptr, /*OffsetOk=*/true);
+  Value *UnderlyingObject =
+      findValue(Ptr, I.getModule()->getDataLayout(), /*OffsetOk=*/true);
   Assert(!isa<ConstantPointerNull>(UnderlyingObject),
          "Undefined behavior: Null pointer dereference", &I);
   Assert(!isa<UndefValue>(UnderlyingObject),
@@ -419,6 +422,7 @@ void Lint::visitMemoryReference(Instruction &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
@@ -429,21 +433,21 @@ 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);
       }
     }
 
@@ -456,8 +460,8 @@ void Lint::visitMemoryReference(Instruction &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);
+    if (Align == 0 && Ty && Ty->isSized())
+      Align = DL.getABITypeAlignment(Ty);
     Assert(!BaseAlign || Align <= MinAlign(BaseAlign, Offset),
            "Undefined behavior: Memory reference address is misaligned", &I);
   }
@@ -487,22 +491,23 @@ void Lint::visitSub(BinaryOperator &I) {
 }
 
 void Lint::visitLShr(BinaryOperator &I) {
-  if (ConstantInt *CI =
-        dyn_cast<ConstantInt>(findValue(I.getOperand(1), /*OffsetOk=*/false)))
+  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)))
+  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)))
+  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);
 }
@@ -688,7 +693,7 @@ void Lint::visitEHEndCatch(IntrinsicInst *II) {
          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))
@@ -729,22 +734,22 @@ static bool isZero(Value *V, const DataLayout *DL, DominatorTree *DT,
 }
 
 void Lint::visitSDiv(BinaryOperator &I) {
-  Assert(!isZero(I.getOperand(1), DL, DT, AC),
+  Assert(!isZero(I.getOperand(1), I.getModule()->getDataLayout(), DT, AC),
          "Undefined behavior: Division by zero", &I);
 }
 
 void Lint::visitUDiv(BinaryOperator &I) {
-  Assert(!isZero(I.getOperand(1), DL, DT, AC),
+  Assert(!isZero(I.getOperand(1), I.getModule()->getDataLayout(), DT, AC),
          "Undefined behavior: Division by zero", &I);
 }
 
 void Lint::visitSRem(BinaryOperator &I) {
-  Assert(!isZero(I.getOperand(1), DL, DT, AC),
+  Assert(!isZero(I.getOperand(1), I.getModule()->getDataLayout(), DT, AC),
          "Undefined behavior: Division by zero", &I);
 }
 
 void Lint::visitURem(BinaryOperator &I) {
-  Assert(!isZero(I.getOperand(1), DL, DT, AC),
+  Assert(!isZero(I.getOperand(1), I.getModule()->getDataLayout(), DT, AC),
          "Undefined behavior: Division by zero", &I);
 }
 
@@ -771,17 +776,17 @@ void Lint::visitIndirectBrInst(IndirectBrInst &I) {
 }
 
 void Lint::visitExtractElementInst(ExtractElementInst &I) {
-  if (ConstantInt *CI =
-        dyn_cast<ConstantInt>(findValue(I.getIndexOperand(),
-                                        /*OffsetOk=*/false)))
+  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)))
+  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);
 }
@@ -802,13 +807,13 @@ 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)
@@ -829,7 +834,7 @@ 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;
@@ -838,40 +843,38 @@ 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;