[WebAssembly] Reorganize address offset folding.

[oota-llvm.git] / lib / Analysis / ValueTracking.cpp

diff --git a/lib/Analysis/ValueTracking.cpp b/lib/Analysis/ValueTracking.cpp
index d6a78411388818969fe8aa4212687d96f1a7c664..abc57ed8bca06770df264cd8d55b3fd13ee4db67 100644 (file)
--- a/lib/Analysis/ValueTracking.cpp
+++ b/lib/Analysis/ValueTracking.cpp
@@ -2830,7 +2830,12 @@ Value *llvm::GetPointerBaseWithConstantOffset(Value *Ptr, int64_t &Offset,
                                               const DataLayout &DL) {
   unsigned BitWidth = DL.getPointerTypeSizeInBits(Ptr->getType());
   APInt ByteOffset(BitWidth, 0);
-  while (1) {
+
+  // We walk up the defs but use a visited set to handle unreachable code. In
+  // that case, we stop after accumulating the cycle once (not that it
+  // matters).
+  SmallPtrSet<Value *, 16> Visited;
+  while (Visited.insert(Ptr).second) {
     if (Ptr->getType()->isVectorTy())
       break;
 
@@ -3269,12 +3274,9 @@ static bool isDereferenceableAndAlignedPointer(
   }
 
   // For gc.relocate, look through relocations
-  if (const IntrinsicInst *I = dyn_cast<IntrinsicInst>(V))
-    if (I->getIntrinsicID() == Intrinsic::experimental_gc_relocate) {
-      GCRelocateOperands RelocateInst(I);
-      return isDereferenceableAndAlignedPointer(
-          RelocateInst.getDerivedPtr(), Align, DL, CtxI, DT, TLI, Visited);
-    }
+  if (const GCRelocateInst *RelocateInst = dyn_cast<GCRelocateInst>(V))
+    return isDereferenceableAndAlignedPointer(
+        RelocateInst->getDerivedPtr(), Align, DL, CtxI, DT, TLI, Visited);
 
   if (const AddrSpaceCastInst *ASC = dyn_cast<AddrSpaceCastInst>(V))
     return isDereferenceableAndAlignedPointer(ASC->getOperand(0), Align, DL,
@@ -3475,10 +3477,6 @@ bool llvm::isKnownNonNull(const Value *V, const TargetLibraryInfo *TLI) {
     if (CS.isReturnNonNull())
       return true;
 
-  // operator new never returns null.
-  if (isOperatorNewLikeFn(V, TLI, /*LookThroughBitCast=*/true))
-    return true;
-
   return false;
 }