[opaque pointer types] Pass value type to GetElementPtr creation.

This cleans up all GetElementPtr creation in LLVM to explicitly pass a
value type rather than deriving it from the pointer's element-type.

Differential Revision: https://reviews.llvm.org/D57173

llvm-svn: 352913

llvm/lib/Bitcode/Reader/BitcodeReader.cpp

@@ -2424,16 +2424,18 @@ Error BitcodeReader::parseConstants() {
         Elts.push_back(ValueList.getConstantFwdRef(Record[OpNum++], ElTy));
       }
 
-      if (PointeeType &&
-          PointeeType !=
-              cast<PointerType>(Elts[0]->getType()->getScalarType())
-                  ->getElementType())
-        return error("Explicit gep operator type does not match pointee type "
-                     "of pointer operand");
-
       if (Elts.size() < 1)
         return error("Invalid gep with no operands");
 
+      Type *ImplicitPointeeType =
+          cast<PointerType>(Elts[0]->getType()->getScalarType())
+              ->getElementType();
+      if (!PointeeType)
+        PointeeType = ImplicitPointeeType;
+      else if (PointeeType != ImplicitPointeeType)
+        return error("Explicit gep operator type does not match pointee type "
+                     "of pointer operand");
+
       ArrayRef<Constant *> Indices(Elts.begin() + 1, Elts.end());
       V = ConstantExpr::getGetElementPtr(PointeeType, Elts[0], Indices,
                                          InBounds, InRangeIndex);