Remove GenTreeIndexAddr::gtStructElemClass

There is no need to store this. GenTreeIndexAddr is only used in minopts where VN doesn't run. It's only remaining use is to recover the struct handle in gtGetStructHandleIfPresent. But that can be done by generating a OBJ instead of IND in fgMorphArrayIndex.

src/jit/compiler.h

@@ -9569,14 +9569,6 @@ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
  return false;
  }
 
- if (indir->gtOp1->OperIs(GT_INDEX_ADDR))
- {
- GenTreeIndexAddr* const indexAddr = indir->gtOp1->AsIndexAddr();
- *arrayInfo = ArrayInfo(indexAddr->gtElemType, indexAddr->gtElemSize, indexAddr->gtElemOffset,
- indexAddr->gtStructElemClass);
- return true;
- }
-
  bool found = GetArrayInfoMap()->Lookup(indir, arrayInfo);
  assert(found);
  return true;

src/jit/gentree.cpp

@@ -245,7 +245,7 @@ void GenTree::InitNodeSize()
  GenTree::s_gtNodeSizes[GT_FTN_ADDR] = TREE_NODE_SZ_LARGE;
  GenTree::s_gtNodeSizes[GT_BOX] = TREE_NODE_SZ_LARGE;
  GenTree::s_gtNodeSizes[GT_INDEX] = TREE_NODE_SZ_LARGE;
- GenTree::s_gtNodeSizes[GT_INDEX_ADDR]  = TREE_NODE_SZ_LARGE;
+ GenTree::s_gtNodeSizes[GT_INDEX_ADDR] = TREE_NODE_SZ_LARGE;
  GenTree::s_gtNodeSizes[GT_ARR_BOUNDS_CHECK] = TREE_NODE_SZ_LARGE;
 #ifdef FEATURE_SIMD
  GenTree::s_gtNodeSizes[GT_SIMD_CHK] = TREE_NODE_SZ_LARGE;
@@ -7038,9 +7038,8 @@ GenTree* Compiler::gtCloneExpr(
  GenTreeIndexAddr* asIndAddr = tree->AsIndexAddr();
 
  copy = new (this, GT_INDEX_ADDR)
- GenTreeIndexAddr(asIndAddr->Arr(), asIndAddr->Index(), asIndAddr->gtElemType,
- asIndAddr->gtStructElemClass, asIndAddr->gtElemSize, asIndAddr->gtLenOffset,
- asIndAddr->gtElemOffset);
+ GenTreeIndexAddr(asIndAddr->Arr(), asIndAddr->Index(), asIndAddr->gtElemType, asIndAddr->gtElemSize,
+ asIndAddr->gtLenOffset, asIndAddr->gtElemOffset);
  copy->AsIndexAddr()->gtIndRngFailBB = asIndAddr->gtIndRngFailBB;
  }
  break;
@@ -16426,9 +16425,6 @@ CORINFO_CLASS_HANDLE Compiler::gtGetStructHandleIfPresent(GenTree* tree)
  case GT_INDEX:
  structHnd = tree->gtIndex.gtStructElemClass;
  break;
- case GT_INDEX_ADDR:
- structHnd = tree->AsIndexAddr()->gtStructElemClass;
- break;
  case GT_FIELD:
  info.compCompHnd->getFieldType(tree->gtField.gtFldHnd, &structHnd);
  break;
@@ -16450,8 +16446,14 @@ CORINFO_CLASS_HANDLE Compiler::gtGetStructHandleIfPresent(GenTree* tree)
  structHnd = gtGetStructHandleIfPresent(tree->gtOp.gtOp1);
  break;
  case GT_IND:
+ if (tree->AsIndir()->Addr()->OperIs(GT_INDEX_ADDR))
+ {
+ // There's no way to recover the handle from a IND(GT_INDEX_ADDR) tree and
+ // that should not be needed.
+ }
+ else
 #ifdef FEATURE_SIMD
- if (varTypeIsSIMD(tree))
+  if (varTypeIsSIMD(tree))
  {
  structHnd = gtGetStructHandleForSIMD(tree->gtType, TYP_FLOAT);
 #ifdef FEATURE_HW_INTRINSICS

src/jit/gentree.h

@@ -4321,24 +4321,16 @@ struct GenTreeIndexAddr : public GenTreeOp
  return gtOp2;
  }
 
- CORINFO_CLASS_HANDLE gtStructElemClass; // If the element type is a struct, this is the struct type.
-
  BasicBlock* gtIndRngFailBB; // Basic block to jump to for array-index-out-of-range
 
  var_types gtElemType; // The element type of the array.
  unsigned gtElemSize; // size of elements in the array
  unsigned gtLenOffset; // The offset from the array's base address to its length.
  unsigned gtElemOffset; // The offset from the array's base address to its first element.
 
- GenTreeIndexAddr(GenTree* arr,
- GenTree* ind,
- var_types elemType,
- CORINFO_CLASS_HANDLE structElemClass,
- unsigned elemSize,
- unsigned lenOffset,
- unsigned elemOffset)
+ GenTreeIndexAddr(
+ GenTree* arr, GenTree* ind, var_types elemType, unsigned elemSize, unsigned lenOffset, unsigned elemOffset)
  : GenTreeOp(GT_INDEX_ADDR, TYP_BYREF, arr, ind)
- , gtStructElemClass(structElemClass)
  , gtIndRngFailBB(nullptr)
  , gtElemType(elemType)
  , gtElemSize(elemSize)

src/jit/morph.cpp

@@ -5656,8 +5656,8 @@ GenTree* Compiler::fgMorphArrayIndex(GenTree* tree)
  GenTree* const index = fgMorphTree(asIndex->Index());
 
  GenTreeIndexAddr* const indexAddr =
- new (this, GT_INDEX_ADDR) GenTreeIndexAddr(array, index, elemTyp, elemStructType, elemSize,
- static_cast<unsigned>(lenOffs), static_cast<unsigned>(elemOffs));
+ new (this, GT_INDEX_ADDR) GenTreeIndexAddr(array, index, elemTyp, elemSize, static_cast<unsigned>(lenOffs),
+ static_cast<unsigned>(elemOffs));
  indexAddr->gtFlags |= (array->gtFlags | index->gtFlags) & GTF_ALL_EFFECT;
 
  // Mark the indirection node as needing a range check if necessary.
@@ -5667,15 +5667,21 @@ GenTree* Compiler::fgMorphArrayIndex(GenTree* tree)
  fgSetRngChkTarget(indexAddr);
  }
 
- // Change `tree` into an indirection and return.
- tree->ChangeOper(GT_IND);
+ if (elemStructType == NO_CLASS_HANDLE)
+ {
+ tree->ChangeOper(GT_IND);
+ }
+ else
+ {
+ tree->ChangeOper(GT_OBJ);
+ tree->AsObj()->SetLayout(typGetObjLayout(elemStructType));
+ }
+
  GenTreeIndir* const indir = tree->AsIndir();
  indir->Addr() = indexAddr;
- indir->gtFlags = GTF_IND_ARR_INDEX | (indexAddr->gtFlags & GTF_ALL_EFFECT);
+ indir->gtFlags = indexAddr->gtFlags & GTF_ALL_EFFECT;
 
-#ifdef DEBUG
- indexAddr->gtDebugFlags |= GTF_DEBUG_NODE_MORPHED;
-#endif // DEBUG
+ INDEBUG(indexAddr->gtDebugFlags |= GTF_DEBUG_NODE_MORPHED;)
 
  return indir;
  }