openmp, fortran: Add Fortran support for indirect clause on the declare target directive

2024-02-15  Kwok Cheung Yeung  <kcyeung@baylibre.com>

	gcc/fortran/
	* dump-parse-tree.cc (show_attr): Handle omp_declare_target_indirect
	attribute.
	* f95-lang.cc (gfc_gnu_attributes): Add entry for 'omp declare
	target indirect'.
	* gfortran.h (symbol_attribute): Add omp_declare_target_indirect
	field.
	(struct gfc_omp_clauses): Add indirect field.
	* openmp.cc (omp_mask2): Add OMP_CLAUSE_INDIRECT.
	(gfc_match_omp_clauses): Match indirect clause.
	(OMP_DECLARE_TARGET_CLAUSES): Add OMP_CLAUSE_INDIRECT.
	(gfc_match_omp_declare_target): Check omp_device_type and apply
	omp_declare_target_indirect attribute to symbol if indirect clause
	active.  Show warning if there are only device_type and/or indirect
	clauses on the directive.
	* trans-decl.cc (add_attributes_to_decl): Add 'omp declare target
	indirect' attribute if symbol has indirect attribute set.

	gcc/testsuite/
	* gfortran.dg/gomp/declare-target-4.f90 (f1): Update expected warning.
	* gfortran.dg/gomp/declare-target-indirect-1.f90: New.
	* gfortran.dg/gomp/declare-target-indirect-2.f90: New.

	libgomp/
	* testsuite/libgomp.fortran/declare-target-indirect-1.f90: New.
	* testsuite/libgomp.fortran/declare-target-indirect-2.f90: New.
	* testsuite/libgomp.fortran/declare-target-indirect-3.f90: New.

3 files changed, 128 insertions, 0 deletions

diff --git a/libgomp/testsuite/libgomp.fortran/declare-target-indirect-1.f90 b/libgomp/testsuite/libgomp.fortran/declare-target-indirect-1.f90
new file mode 100644
index 0000000..39a91df
--- /dev/null
+++ b/libgomp/testsuite/libgomp.fortran/declare-target-indirect-1.f90
@@ -0,0 +1,39 @@
+! { dg-do run }
+
+module m
+contains
+  integer function foo ()
+    !$omp declare target to (foo) indirect
+    foo = 5
+  end function
+
+  integer function bar ()
+    !$omp declare target to (bar) indirect
+    bar = 8
+  end function
+
+  integer function baz ()
+    !$omp declare target to (baz) indirect
+    baz = 11
+  end function
+end module
+
+program main
+  use m
+  implicit none
+
+  integer :: x, expected
+  procedure (foo), pointer :: foo_ptr, bar_ptr, baz_ptr
+
+  foo_ptr => foo
+  bar_ptr => bar
+  baz_ptr => baz
+
+  expected = foo () + bar () + baz ()
+
+  !$omp target map (to: foo_ptr, bar_ptr, baz_ptr) map (from: x)
+    x = foo_ptr () + bar_ptr () + baz_ptr ()
+  !$omp end target
+
+  stop x - expected
+end program
diff --git a/libgomp/testsuite/libgomp.fortran/declare-target-indirect-2.f90 b/libgomp/testsuite/libgomp.fortran/declare-target-indirect-2.f90
new file mode 100644
index 0000000..34dd277
--- /dev/null
+++ b/libgomp/testsuite/libgomp.fortran/declare-target-indirect-2.f90
@@ -0,0 +1,54 @@
+! { dg-do run }
+! { dg-xfail-run-if "Requires libgomp bug fix pending review" { offload_device } }
+
+module m
+contains
+  integer function foo ()
+    !$omp declare target to (foo) indirect
+    foo = 5
+  end function
+
+  integer function bar ()
+    !$omp declare target to (bar) indirect
+    bar = 8
+  end function
+
+  integer function baz ()
+    !$omp declare target to (baz) indirect
+    baz = 11
+  end function
+end module
+
+program main
+  use m
+  implicit none
+
+  type fp
+    procedure (foo), pointer, nopass :: f => null ()
+  end type
+
+  integer, parameter :: N = 256
+  integer :: i, x = 0, expected = 0;
+  type (fp) :: fn_ptr (N)
+
+  do i = 1, N
+    select case (mod (i, 3))
+      case (0)
+        fn_ptr (i)%f => foo
+      case (1)
+        fn_ptr (i)%f => bar
+      case (2)
+        fn_ptr (i)%f => baz
+    end select
+    expected = expected + fn_ptr (i)%f ()
+  end do
+
+  !$omp target teams distribute parallel do &
+  !$omp & reduction(+: x) map (to: fn_ptr) map (tofrom: x)
+    do i = 1, N
+      x = x + fn_ptr (i)%f ()
+    end do
+  !$omp end target teams distribute parallel do
+
+  stop x - expected
+end program
diff --git a/libgomp/testsuite/libgomp.fortran/declare-target-indirect-3.f90 b/libgomp/testsuite/libgomp.fortran/declare-target-indirect-3.f90
new file mode 100644
index 0000000..00f33bd
--- /dev/null
+++ b/libgomp/testsuite/libgomp.fortran/declare-target-indirect-3.f90
@@ -0,0 +1,35 @@
+! { dg-do run }
+
+! Check that indirect calls work on procedures passed in via a dummy argument
+
+module m
+  integer, parameter :: offset = 123
+contains
+  function bar(x)
+    !$omp declare target enter (bar) indirect
+    integer :: bar
+    integer, intent(in) :: x
+    bar = x + offset
+  end function
+
+  function foo(f, x)
+    integer :: foo
+    procedure(bar) :: f
+    integer, intent(in) :: x
+
+    !$omp target map (to: x) map (from: foo)
+      foo = f(x)
+    !$omp end target
+  end function
+end module
+
+program main
+  use m
+  implicit none
+
+  integer :: a = 321
+  integer :: b
+
+  b = foo(bar, a)
+  stop b - (a + offset)
+end program