[PATCH] D35498: [LoopVectorizer] Use two step casting for float to pointer type.

[Manoj Gupta via Phabricator via llvm-commits]

manojgupta created this revision.
Herald added subscribers: mzolotukhin, rengolin.

Is is illegal to drectly cast a floating point type to a pointer type
even if the types have same size. Use a two-step casting by bitcasting
to integer and integer to pointer to avoid a crash.
Fixes PR33804.


https://reviews.llvm.org/D35498

Files:
  lib/Transforms/Vectorize/LoopVectorize.cpp


Index: lib/Transforms/Vectorize/LoopVectorize.cpp
===================================================================
--- lib/Transforms/Vectorize/LoopVectorize.cpp
+++ lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -2949,8 +2949,26 @@
         StoredVec = reverseVector(StoredVec);
 
       // If this member has different type, cast it to an unified type.
-      if (StoredVec->getType() != SubVT)
+      if (StoredVec->getType() != SubVT) {
+        const DataLayout &DL = Member->getModule()->getDataLayout();
+        if (!CastInst::isBitOrNoopPointerCastable(StoredVec->getType(), SubVT, DL)) {
+          // StoredVec cannot be directly casted to SubVT type.
+          // May happen when StoredVec is Floating point vector but SubVT is a
+          // pointer type.
+          const Type* SrcElemTy = cast<VectorType>(StoredVec->getType())->getElementType();
+          if (ScalarTy->isPointerTy() && SrcElemTy->isFloatingPointTy()) {
+            // Needs two step casting. First bitcast floating type to an int type.
+            // Int type can be safely casted to the pointer type.
+            Type* IntTy = IntegerType::getIntNTy(Member->getContext(), SrcElemTy->getPrimitiveSizeInBits());
+            VectorType *VecIntTy = VectorType::get(IntTy, VF);
+            StoredVec = Builder.CreateBitOrPointerCast(StoredVec, VecIntTy);
+          } else {
+            // Casting is not possible.
+            return;
+          }
+        }
         StoredVec = Builder.CreateBitOrPointerCast(StoredVec, SubVT);
+      }
 
       StoredVecs.push_back(StoredVec);
     }


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