[flang] Use fir.type_desc in nullify

Do not look for the global early in nullify codegen. The type descriptor
can be emitted later and it would raise an error as it could not be found.
Use `fir.type_desc` instead so it delays the type descriptor lookup until
evrything is emitted.

#63775

Reviewed By: vzakhari

Differential Revision: https://reviews.llvm.org/D154982

Author: clementval

flang/lib/Optimizer/Builder/Runtime/Derived.cpp

@@ -50,21 +50,15 @@ void fir::runtime::genNullifyDerivedType(fir::FirOpBuilder &builder,
                                          mlir::Location loc, mlir::Value box,
                                          fir::RecordType derivedType,
                                          unsigned rank) {
-  std::string typeDescName =
-      fir::NameUniquer::getTypeDescriptorName(derivedType.getName());
-  fir::GlobalOp typeDescGlobal = builder.getNamedGlobal(typeDescName);
-  if (!typeDescGlobal)
-    fir::emitFatalError(loc, "no type descriptor found for NULLIFY");
-  auto typeDescAddr = builder.create<fir::AddrOfOp>(
-      loc, fir::ReferenceType::get(typeDescGlobal.getType()),
-      typeDescGlobal.getSymbol());
+  mlir::Value typeDesc =
+      builder.create<fir::TypeDescOp>(loc, mlir::TypeAttr::get(derivedType));
   mlir::func::FuncOp callee =
       fir::runtime::getRuntimeFunc<mkRTKey(PointerNullifyDerived)>(loc,
                                                                    builder);
   llvm::ArrayRef<mlir::Type> inputTypes = callee.getFunctionType().getInputs();
   llvm::SmallVector<mlir::Value> args;
   args.push_back(builder.createConvert(loc, inputTypes[0], box));
-  args.push_back(builder.createConvert(loc, inputTypes[1], typeDescAddr));
+  args.push_back(builder.createConvert(loc, inputTypes[1], typeDesc));
   mlir::Value rankCst = builder.createIntegerConstant(loc, inputTypes[2], rank);
   mlir::Value c0 = builder.createIntegerConstant(loc, inputTypes[3], 0);
   args.push_back(rankCst);

flang/test/Lower/nullify-polymorphic.f90

@@ -44,9 +44,9 @@ program test
 ! CHECK-LABEL: func.func @_QMpolyPtest_nullify()
 ! CHECK: %[[C_DESC:.*]] = fir.alloca !fir.class<!fir.ptr<!fir.type<_QMpolyTp1{a:i32,b:i32}>>> {bindc_name = "c", uniq_name = "_QMpolyFtest_nullifyEc"}
 ! CHECK: %{{.*}} = fir.call @_FortranAPointerAllocate(%{{.*}}, %{{.*}}, %{{.*}}, %{{.*}}, %{{.*}}) {{.*}}: (!fir.ref<!fir.box<none>>, i1, !fir.box<none>, !fir.ref<i8>, i32) -> i32
-! CHECK: %[[DECLARED_TYPE:.*]] = fir.address_of(@_QMpolyE.dt.p1) : !fir.ref<!fir.type<{{.*}}>>
+! CHECK: %[[DECLARED_TYPE_DESC:.*]] = fir.type_desc !fir.type<_QMpolyTp1{a:i32,b:i32}> 
 ! CHECK: %[[C_DESC_CAST:.*]] = fir.convert %[[C_DESC]] : (!fir.ref<!fir.class<!fir.ptr<!fir.type<_QMpolyTp1{a:i32,b:i32}>>>>) -> !fir.ref<!fir.box<none>>
-! CHECK: %[[TYPE_DESC_CAST:.*]] = fir.convert %[[DECLARED_TYPE]] : (!fir.ref<!fir.type<{{.*}}>>) -> !fir.ref<none>
+! CHECK: %[[TYPE_DESC_CAST:.*]] = fir.convert %[[DECLARED_TYPE_DESC]] : (!fir.tdesc<!fir.type<_QMpolyTp1{a:i32,b:i32}>>) -> !fir.ref<none>
 ! CHECK: %[[RANK:.*]] = arith.constant 0 : i32
 ! CHECK: %[[CORANK:.*]] = arith.constant 0 : i32
 ! CHECK: %{{.*}} = fir.call @_FortranAPointerNullifyDerived(%[[C_DESC_CAST]], %[[TYPE_DESC_CAST]], %[[RANK]], %[[CORANK]]) {{.*}}: (!fir.ref<!fir.box<none>>, !fir.ref<none>, i32, i32) -> none

flang/test/Lower/pointer-disassociate.f90

@@ -113,9 +113,9 @@ subroutine test_polymorphic_null(p)
 end subroutine
 ! CHECK-LABEL:   func.func @_QPtest_polymorphic_null(
 ! CHECK-SAME:  %[[VAL_0:.*]]: !fir.ref<!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFtest_polymorphic_nullTt>>>>>
-! CHECK:  %[[VAL_1:.*]] = fir.address_of(@_QFtest_polymorphic_nullE.dt.t)
+! CHECK:  %[[VAL_1:.*]] = fir.type_desc !fir.type<_QFtest_polymorphic_nullTt> 
 ! CHECK:  %[[VAL_2:.*]] = fir.convert %[[VAL_0]] : (!fir.ref<!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QFtest_polymorphic_nullTt>>>>>) -> !fir.ref<!fir.box<none>>
-! CHECK:  %[[VAL_3:.*]] = fir.convert %[[VAL_1]] : (!fir.ref<{{.*}}>) -> !fir.ref<none>
+! CHECK:  %[[VAL_3:.*]] = fir.convert %[[VAL_1]] : (!fir.tdesc<!fir.type<_QFtest_polymorphic_nullTt>>) -> !fir.ref<none> 
 ! CHECK:  %[[VAL_4:.*]] = arith.constant 1 : i32
 ! CHECK:  %[[VAL_5:.*]] = arith.constant 0 : i32
 ! CHECK:  %[[VAL_6:.*]] = fir.call @_FortranAPointerNullifyDerived(%[[VAL_2]], %[[VAL_3]], %[[VAL_4]], %[[VAL_5]]) {{.*}}: (!fir.ref<!fir.box<none>>, !fir.ref<none>, i32, i32) -> none

flang/test/Lower/polymorphic.f90

@@ -310,9 +310,9 @@ subroutine nullify_pointer_array(a)
 ! CHECK-SAME: %[[ARG0:.*]]: !fir.ref<!fir.type<_QMpolymorphic_testTp3{p:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QMpolymorphic_testTp3>>>>}>> {fir.bindc_name = "a"}) {
 ! CHECK: %[[FIELD_P:.*]] = fir.field_index p, !fir.type<_QMpolymorphic_testTp3{p:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QMpolymorphic_testTp3>>>>}>
 ! CHECK: %[[COORD_P:.*]] = fir.coordinate_of %[[ARG0]], %[[FIELD_P]] : (!fir.ref<!fir.type<_QMpolymorphic_testTp3{p:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QMpolymorphic_testTp3>>>>}>>, !fir.field) -> !fir.ref<!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QMpolymorphic_testTp3{p:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QMpolymorphic_testTp3>>>>}>>>>>
-! CHECK: %[[TYPE_DESC_ADDR:.*]] = fir.address_of(@_QMpolymorphic_testE.dt.p3) : !fir.ref<!fir.type<{{.*}}>>
+! CHECK: %[[TYPE_DESC:.*]] = fir.type_desc !fir.type<_QMpolymorphic_testTp3{p:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QMpolymorphic_testTp3>>>>}> 
 ! CHECK: %[[CONV_P:.*]] = fir.convert %[[COORD_P]] : (!fir.ref<!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QMpolymorphic_testTp3{p:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QMpolymorphic_testTp3>>>>}>>>>>) -> !fir.ref<!fir.box<none>>
-! CHECK: %[[CONV_TDESC:.*]] = fir.convert %[[TYPE_DESC_ADDR]] : (!fir.ref<!fir.type<{{.*}}>>) -> !fir.ref<none>
+! CHECK: %[[CONV_TDESC:.*]] = fir.convert %[[TYPE_DESC]] : (!fir.tdesc<!fir.type<_QMpolymorphic_testTp3{p:!fir.class<!fir.ptr<!fir.array<?x!fir.type<_QMpolymorphic_testTp3>>>>}>>) -> !fir.ref<none>
 ! CHECK: %[[C1:.*]] = arith.constant 1 : i32
 ! CHECK: %[[C0:.*]] = arith.constant 0 : i32
 ! CHECK: %{{.*}} = fir.call @_FortranAPointerNullifyDerived(%[[CONV_P]], %[[CONV_TDESC]], %[[C1]], %[[C0]]) {{.*}} : (!fir.ref<!fir.box<none>>, !fir.ref<none>, i32, i32) -> none