[llvm] [SPIR-V] Scalarize vector of pointers for ptrtoint/inttoptr (PR #184817)

[Dmitry Sidorov via llvm-commits]

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@@ -2106,6 +2115,58 @@ SPIRVEmitIntrinsics::visitExtractElementInst(ExtractElementInst &I) {
   return NewI;
 }
 
+Instruction *SPIRVEmitIntrinsics::visitPtrToIntInst(PtrToIntInst &I) {
+  // Scalarize ptrtoint on vectors of pointers, since SPIR-V does not support
+  // vectors of pointers.
+  Type *SrcTy = I.getOperand(0)->getType();
+  auto *VecTy = dyn_cast<FixedVectorType>(SrcTy);
+
+  if (!VecTy || !VecTy->getElementType()->isPointerTy())
+    return &I;
+
+  IRBuilder<> B(I.getParent());
+  B.SetInsertPoint(&I);
+
+  unsigned NumElems = VecTy->getNumElements();
+  Type *ElemIntTy = cast<VectorType>(I.getType())->getElementType();
+  Value *Result = PoisonValue::get(I.getType());
+
+  for (unsigned Idx = 0; Idx < NumElems; ++Idx) {
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MrSidims wrote:

Would it makes sense to move unrolling logic into a new utility function, that could be reused to lower not only ptrtoint/inttoptr instructions but also others, that may be operating over a vector of pointers? Like it's being done https://github.com/llvm/llvm-project/blob/main/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp#L13700 

https://github.com/llvm/llvm-project/pull/184817