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, 34 insertions, 68 deletions

diff --git a/llvm/lib/Analysis/ScalarEvolution.cpp b/llvm/lib/Analysis/ScalarEvolution.cpp
index 3ccbd14438d..dcff7b60fb7 100644
--- a/llvm/lib/Analysis/ScalarEvolution.cpp
+++ b/llvm/lib/Analysis/ScalarEvolution.cpp
@@ -3130,39 +3130,23 @@ const SCEV *ScalarEvolution::getUMinExpr(const SCEV *LHS,
 }
 
 const SCEV *ScalarEvolution::getSizeOfExpr(Type *IntTy, Type *AllocTy) {
-  // If we have DataLayout, we can bypass creating a target-independent
+  // We can bypass creating a target-independent
   // constant expression and then folding it back into a ConstantInt.
   // This is just a compile-time optimization.
-  if (DL)
-    return getConstant(IntTy, DL->getTypeAllocSize(AllocTy));
-
-  Constant *C = ConstantExpr::getSizeOf(AllocTy);
-  if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C))
-    if (Constant *Folded = ConstantFoldConstantExpression(CE, DL, TLI))
-      C = Folded;
-  Type *Ty = getEffectiveSCEVType(PointerType::getUnqual(AllocTy));
-  assert(Ty == IntTy && "Effective SCEV type doesn't match");
-  return getTruncateOrZeroExtend(getSCEV(C), Ty);
+  return getConstant(IntTy,
+                     F->getParent()->getDataLayout().getTypeAllocSize(AllocTy));
 }
 
 const SCEV *ScalarEvolution::getOffsetOfExpr(Type *IntTy,
                                              StructType *STy,
                                              unsigned FieldNo) {
-  // If we have DataLayout, we can bypass creating a target-independent
+  // We can bypass creating a target-independent
   // constant expression and then folding it back into a ConstantInt.
   // This is just a compile-time optimization.
-  if (DL) {
-    return getConstant(IntTy,
-                       DL->getStructLayout(STy)->getElementOffset(FieldNo));
-  }
-
-  Constant *C = ConstantExpr::getOffsetOf(STy, FieldNo);
-  if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C))
-    if (Constant *Folded = ConstantFoldConstantExpression(CE, DL, TLI))
-      C = Folded;
-
-  Type *Ty = getEffectiveSCEVType(PointerType::getUnqual(STy));
-  return getTruncateOrZeroExtend(getSCEV(C), Ty);
+  return getConstant(
+      IntTy,
+      F->getParent()->getDataLayout().getStructLayout(STy)->getElementOffset(
+          FieldNo));
 }
 
 const SCEV *ScalarEvolution::getUnknown(Value *V) {
@@ -3204,19 +3188,7 @@ bool ScalarEvolution::isSCEVable(Type *Ty) const {
 /// for which isSCEVable must return true.
 uint64_t ScalarEvolution::getTypeSizeInBits(Type *Ty) const {
   assert(isSCEVable(Ty) && "Type is not SCEVable!");
-
-  // If we have a DataLayout, use it!
-  if (DL)
-    return DL->getTypeSizeInBits(Ty);
-
-  // Integer types have fixed sizes.
-  if (Ty->isIntegerTy())
-    return Ty->getPrimitiveSizeInBits();
-
-  // The only other support type is pointer. Without DataLayout, conservatively
-  // assume pointers are 64-bit.
-  assert(Ty->isPointerTy() && "isSCEVable permitted a non-SCEVable type!");
-  return 64;
+  return F->getParent()->getDataLayout().getTypeSizeInBits(Ty);
 }
 
 /// getEffectiveSCEVType - Return a type with the same bitwidth as
@@ -3232,12 +3204,7 @@ Type *ScalarEvolution::getEffectiveSCEVType(Type *Ty) const {
 
   // The only other support type is pointer.
   assert(Ty->isPointerTy() && "Unexpected non-pointer non-integer type!");
-
-  if (DL)
-    return DL->getIntPtrType(Ty);
-
-  // Without DataLayout, conservatively assume pointers are 64-bit.
-  return Type::getInt64Ty(getContext());
+  return F->getParent()->getDataLayout().getIntPtrType(Ty);
 }
 
 const SCEV *ScalarEvolution::getCouldNotCompute() {
@@ -3701,7 +3668,8 @@ const SCEV *ScalarEvolution::createNodeForPHI(PHINode *PN) {
   // PHI's incoming blocks are in a different loop, in which case doing so
   // risks breaking LCSSA form. Instcombine would normally zap these, but
   // it doesn't have DominatorTree information, so it may miss cases.
-  if (Value *V = SimplifyInstruction(PN, DL, TLI, DT, AC))
+  if (Value *V =
+          SimplifyInstruction(PN, F->getParent()->getDataLayout(), TLI, DT, AC))
     if (LI->replacementPreservesLCSSAForm(PN, V))
       return getSCEV(V);
 
@@ -3833,7 +3801,8 @@ ScalarEvolution::GetMinTrailingZeros(const SCEV *S) {
     // For a SCEVUnknown, ask ValueTracking.
     unsigned BitWidth = getTypeSizeInBits(U->getType());
     APInt Zeros(BitWidth, 0), Ones(BitWidth, 0);
-    computeKnownBits(U->getValue(), Zeros, Ones, DL, 0, AC, nullptr, DT);
+    computeKnownBits(U->getValue(), Zeros, Ones,
+                     F->getParent()->getDataLayout(), 0, AC, nullptr, DT);
     return Zeros.countTrailingOnes();
   }
 
@@ -4063,7 +4032,7 @@ ScalarEvolution::getRange(const SCEV *S,
     // Split here to avoid paying the compile-time cost of calling both
     // computeKnownBits and ComputeNumSignBits.  This restriction can be lifted
     // if needed.
-
+    const DataLayout &DL = F->getParent()->getDataLayout();
     if (SignHint == ScalarEvolution::HINT_RANGE_UNSIGNED) {
       // For a SCEVUnknown, ask ValueTracking.
       APInt Zeros(BitWidth, 0), Ones(BitWidth, 0);
@@ -4074,13 +4043,11 @@ ScalarEvolution::getRange(const SCEV *S,
     } else {
       assert(SignHint == ScalarEvolution::HINT_RANGE_SIGNED &&
              "generalize as needed!");
-      if (U->getValue()->getType()->isIntegerTy() || DL) {
-        unsigned NS = ComputeNumSignBits(U->getValue(), DL, 0, AC, nullptr, DT);
-        if (NS > 1)
-          ConservativeResult = ConservativeResult.intersectWith(ConstantRange(
-              APInt::getSignedMinValue(BitWidth).ashr(NS - 1),
-              APInt::getSignedMaxValue(BitWidth).ashr(NS - 1) + 1));
-      }
+      unsigned NS = ComputeNumSignBits(U->getValue(), DL, 0, AC, nullptr, DT);
+      if (NS > 1)
+        ConservativeResult = ConservativeResult.intersectWith(
+            ConstantRange(APInt::getSignedMinValue(BitWidth).ashr(NS - 1),
+                          APInt::getSignedMaxValue(BitWidth).ashr(NS - 1) + 1));
     }
 
     return setRange(U, SignHint, ConservativeResult);
@@ -4185,8 +4152,8 @@ const SCEV *ScalarEvolution::createSCEV(Value *V) {
       unsigned TZ = A.countTrailingZeros();
       unsigned BitWidth = A.getBitWidth();
       APInt KnownZero(BitWidth, 0), KnownOne(BitWidth, 0);
-      computeKnownBits(U->getOperand(0), KnownZero, KnownOne, DL, 0, AC,
-                       nullptr, DT);
+      computeKnownBits(U->getOperand(0), KnownZero, KnownOne,
+                       F->getParent()->getDataLayout(), 0, AC, nullptr, DT);
 
       APInt EffectiveMask =
           APInt::getLowBitsSet(BitWidth, BitWidth - LZ - TZ).shl(TZ);
@@ -5413,7 +5380,7 @@ static PHINode *getConstantEvolvingPHI(Value *V, const Loop *L) {
 /// reason, return null.
 static Constant *EvaluateExpression(Value *V, const Loop *L,
                                     DenseMap<Instruction *, Constant *> &Vals,
-                                    const DataLayout *DL,
+                                    const DataLayout &DL,
                                     const TargetLibraryInfo *TLI) {
   // Convenient constant check, but redundant for recursive calls.
   if (Constant *C = dyn_cast<Constant>(V)) return C;
@@ -5502,6 +5469,7 @@ ScalarEvolution::getConstantEvolutionLoopExitValue(PHINode *PN,
 
   unsigned NumIterations = BEs.getZExtValue(); // must be in range
   unsigned IterationNum = 0;
+  const DataLayout &DL = F->getParent()->getDataLayout();
   for (; ; ++IterationNum) {
     if (IterationNum == NumIterations)
       return RetVal = CurrentIterVals[PN];  // Got exit value!
@@ -5509,8 +5477,8 @@ ScalarEvolution::getConstantEvolutionLoopExitValue(PHINode *PN,
     // Compute the value of the PHIs for the next iteration.
     // EvaluateExpression adds non-phi values to the CurrentIterVals map.
     DenseMap<Instruction *, Constant *> NextIterVals;
-    Constant *NextPHI = EvaluateExpression(BEValue, L, CurrentIterVals, DL,
-                                           TLI);
+    Constant *NextPHI =
+        EvaluateExpression(BEValue, L, CurrentIterVals, DL, TLI);
     if (!NextPHI)
       return nullptr;        // Couldn't evaluate!
     NextIterVals[PN] = NextPHI;
@@ -5586,12 +5554,11 @@ const SCEV *ScalarEvolution::ComputeExitCountExhaustively(const Loop *L,
   // Okay, we find a PHI node that defines the trip count of this loop.  Execute
   // the loop symbolically to determine when the condition gets a value of
   // "ExitWhen".
-
   unsigned MaxIterations = MaxBruteForceIterations;   // Limit analysis.
+  const DataLayout &DL = F->getParent()->getDataLayout();
   for (unsigned IterationNum = 0; IterationNum != MaxIterations;++IterationNum){
-    ConstantInt *CondVal =
-      dyn_cast_or_null<ConstantInt>(EvaluateExpression(Cond, L, CurrentIterVals,
-                                                       DL, TLI));
+    ConstantInt *CondVal = dyn_cast_or_null<ConstantInt>(
+        EvaluateExpression(Cond, L, CurrentIterVals, DL, TLI));
 
     // Couldn't symbolically evaluate.
     if (!CondVal) return getCouldNotCompute();
@@ -5824,16 +5791,16 @@ const SCEV *ScalarEvolution::computeSCEVAtScope(const SCEV *V, const Loop *L) {
         // Check to see if getSCEVAtScope actually made an improvement.
         if (MadeImprovement) {
           Constant *C = nullptr;
+          const DataLayout &DL = F->getParent()->getDataLayout();
           if (const CmpInst *CI = dyn_cast<CmpInst>(I))
-            C = ConstantFoldCompareInstOperands(CI->getPredicate(),
-                                                Operands[0], Operands[1], DL,
-                                                TLI);
+            C = ConstantFoldCompareInstOperands(CI->getPredicate(), Operands[0],
+                                                Operands[1], DL, TLI);
           else if (const LoadInst *LI = dyn_cast<LoadInst>(I)) {
             if (!LI->isVolatile())
               C = ConstantFoldLoadFromConstPtr(Operands[0], DL);
           } else
-            C = ConstantFoldInstOperands(I->getOpcode(), I->getType(),
-                                         Operands, DL, TLI);
+            C = ConstantFoldInstOperands(I->getOpcode(), I->getType(), Operands,
+                                         DL, TLI);
           if (!C) return V;
           return getSCEV(C);
         }
@@ -7966,7 +7933,6 @@ bool ScalarEvolution::runOnFunction(Function &F) {
   this->F = &F;
   AC = &getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F);
   LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
-  DL = &F.getParent()->getDataLayout();
   TLI = &getAnalysis<TargetLibraryInfoWrapperPass>().getTLI();
   DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
   return false;