[flang-commits] [flang] [llvm] [Flang] Adding lowering for the allocation and deallocation of coarrays (PR #182110)

[Dan Bonachea via flang-commits]

================
@@ -0,0 +1,45 @@
+//===-- runtime/coarray.cpp -----------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "flang/Runtime/coarray.h"
+#include "flang-rt/runtime/descriptor.h"
+#include "flang-rt/runtime/terminator.h"
+#include "flang-rt/runtime/type-info.h"
+
+namespace Fortran::runtime {
+
+extern "C" {
+RT_EXT_API_GROUP_BEGIN
+
+void RTDEF(ComputeLastUcobound)(
+    int num_images, const Descriptor &lcobounds, const Descriptor &ucobounds) {
+  int corank = ucobounds.GetDimension(0).Extent();
+  if (corank > 15)
+    Fortran::runtime::Terminator{}.Crash(
+        "Fortran runtime error: maximum corank for a coarray is 15, current "
+        "corank is %d.",
+        corank);
+
+  int64_t *lcobounds_ptr = (int64_t *)lcobounds.raw().base_addr;
+  int64_t *ucobounds_ptr = (int64_t *)ucobounds.raw().base_addr;
+  int64_t index = 1;
+  for (int i = 0; i < corank - 1; i++) {
+    index *= ucobounds_ptr[i] - lcobounds_ptr[i] + 1;
+  }
+  if (corank == 1)
+    ucobounds_ptr[0] = lcobounds_ptr[0] + num_images;
+  else if (index < num_images)
+    ucobounds_ptr[corank - 1] =
+        (num_images / index) + (num_images % index != 0);
----------------
bonachea wrote:

This case is also not quite right:


```suggestion
  else if (index < num_images)
    ucobounds_ptr[corank - 1] = lcobounds_ptr[corank - 1] + 
        (num_images / index) + (num_images % index != 0) - 1;
```



https://github.com/llvm/llvm-project/pull/182110