[Flang] Cray pointer Lowering
This patch is to add cray pointer (aka integer pointer) support to flang. Syntax and semantic checking were already available in flang.
Cray pointers reference (https://gcc.gnu.org/onlinedocs/gfortran/Cray-pointers.html)
In order to implement the feature we create the following sequence for a simple scalar load and store:
```
integer pte, i
pointer(ptr, pte)
i = pte
```
```
%1 = fir.alloca i32 {bindc_name = "i", uniq_name = "_QFEi"}
%2 = fir.alloca i32 {bindc_name = "pte", uniq_name = "_QFEpte"}
%3 = fir.alloca i64 {bindc_name = "ptr", uniq_name = "_QFEptr"}
...
%7 = fir.embox %3 : (!fir.ref<i64>) -> !fir.box<i64>
%8 = fir.box_addr %7 : (!fir.box<i64>) -> !fir.ref<i64>
%9 = fir.convert %8 : (!fir.ref<i64>) -> !fir.ref<!fir.ptr<i32>>
%10 = fir.load %9 : !fir.ref<!fir.ptr<i32>>
%11 = fir.load %10 : !fir.ptr<i32>
fir.store %11 to %1 : !fir.ref<i32>
```
```
integer pte, i
pointer(ptr, pte)
pte = i
```
```
%1 = fir.alloca i32 {bindc_name = "i", uniq_name = "_QFEi"}
%2 = fir.alloca i32 {bindc_name = "pte", uniq_name = "_QFEpte"}
%3 = fir.alloca i64 {bindc_name = "ptr", uniq_name = "_QFEptr"}
%7 = fir.load %1 : !fir.ref<i32>
%8 = fir.embox %3 : (!fir.ref<i64>) -> !fir.box<i64>
%9 = fir.box_addr %8 : (!fir.box<i64>) -> !fir.ref<i64>
%10 = fir.convert %9 : (!fir.ref<i64>) -> !fir.ref<!fir.ptr<i32>>
%11 = fir.load %10 : !fir.ref<!fir.ptr<i32>>
fir.store %7 to %11 : !fir.ptr<i32>
```
The sequence is very similar for array element cases with the addition of fir.coordinate_of for the specific element.
The whole array case is slightly different but uses the same sequence before the fir.array_load and fir.array_merge_store.
Reviewed By: kkwli0
Differential Revision: https://reviews.llvm.org/D151478
diff --git a/flang/lib/Lower/Bridge.cpp b/flang/lib/Lower/Bridge.cpp
index 4b9e1ca..be6004d 100644
--- a/flang/lib/Lower/Bridge.cpp
+++ b/flang/lib/Lower/Bridge.cpp
@@ -3578,6 +3578,26 @@
// to a result variable of one of the other types requires
// conversion to the actual type.
mlir::Type toTy = genType(assign.lhs);
+
+ // If Cray pointee, need to handle the address
+ // Array is handled in genCoordinateOp.
+ if (sym->test(Fortran::semantics::Symbol::Flag::CrayPointee) &&
+ sym->Rank() == 0) {
+ // get the corresponding Cray pointer
+
+ auto ptrSym = Fortran::lower::getPointer(*sym);
+ fir::ExtendedValue ptr =
+ getSymbolExtendedValue(ptrSym, nullptr);
+ mlir::Value ptrVal = fir::getBase(ptr);
+ mlir::Type ptrTy = genType(*ptrSym);
+
+ fir::ExtendedValue pte =
+ getSymbolExtendedValue(*sym, nullptr);
+ mlir::Value pteVal = fir::getBase(pte);
+ mlir::Value cnvrt = Fortran::lower::addCrayPointerInst(
+ loc, *builder, ptrVal, ptrTy, pteVal.getType());
+ addr = builder->create<fir::LoadOp>(loc, cnvrt);
+ }
mlir::Value cast =
isVector ? val
: builder->convertWithSemantics(loc, toTy, val);
