[gcc/devel/omp/gcc-11] Permit calls to builtins and intrinsics in kernels loops.

[gcc/devel/omp/gcc-11] Permit calls to builtins and intrinsics in kernels loops.

[Kwok Yeung]

https://gcc.gnu.org/g:e7ec288791481ace60552f3686daf7063aa0dac6

commit e7ec288791481ace60552f3686daf7063aa0dac6
Author: Sandra Loosemore <sandra@codesourcery.com>
Date:   Sat Aug 22 18:23:26 2020 -0700

    Permit calls to builtins and intrinsics in kernels loops.
    
    This tweak to the OpenACC kernels loop annotation relaxes the
    restrictions on function calls in the loop body.  Normally calls to
    functions not explicitly marked with a parallelism attribute are not
    permitted, but C/C++ builtins and Fortran intrinsics have known
    semantics so we can generally permit those without restriction.  If
    any turn out to be problematical, we can add on here to recognize
    them, or in the processing of the "auto" annotations.
    
    2020-08-22  Sandra Loosemore  <sandra@codesourcery.com>
    
            gcc/c-family/
            * c-omp.c (annotate_loops_in_kernels_regions): Test for
            calls to builtins.
    
            gcc/fortran/
            * openmp.c (check_expr_for_invalid_calls): Check for intrinsic
            functions.
    
            gcc/testsuite/
            * c-c++-common/goacc/kernels-loop-annotation-20.c: New.
            * gfortran.dg/goacc/kernels-loop-annotation-20.f95: New.

Diff:
---
 gcc/c-family/ChangeLog.omp                         |  8 +++++++
 gcc/c-family/c-omp.c                               | 10 +++++----
 gcc/fortran/ChangeLog.omp                          |  8 +++++++
 gcc/fortran/openmp.c                               |  9 +++++---
 gcc/testsuite/ChangeLog.omp                        |  8 +++++++
 .../goacc/kernels-loop-annotation-20.c             | 23 +++++++++++++++++++
 .../goacc/kernels-loop-annotation-20.f95           | 26 ++++++++++++++++++++++
 7 files changed, 85 insertions(+), 7 deletions(-)

diff --git a/gcc/c-family/ChangeLog.omp b/gcc/c-family/ChangeLog.omp
index 90aa0e6a17d..4c99f6ea228 100644
--- a/gcc/c-family/ChangeLog.omp
+++ b/gcc/c-family/ChangeLog.omp
@@ -1,3 +1,11 @@
+2020-08-22  Sandra Loosemore  <sandra@codesourcery.com>
+
+	Allow annotation of loops containing calls to builtins in
+	kernels regions.
+
+	* c-omp.c (annotate_loops_in_kernels_regions): Test for
+	calls to builtins.
+
 2020-08-19  Sandra Loosemore  <sandra@codesourcery.com>
 
 	Annotate inner loops in "acc kernels loop" directives (C/C++).
diff --git a/gcc/c-family/c-omp.c b/gcc/c-family/c-omp.c
index 71875efff55..1532462d263 100644
--- a/gcc/c-family/c-omp.c
+++ b/gcc/c-family/c-omp.c
@@ -3317,8 +3317,9 @@ annotate_loops_in_kernels_regions (tree *nodeptr, int *walk_subtrees,
       break;
 
     case CALL_EXPR:
-      /* Direct function calls to functions marked as OpenACC routines are
-	 allowed.  Reject indirect calls or calls to non-routines.  */
+      /* Direct function calls to builtins and functions marked as
+	 OpenACC routines are allowed.  Reject indirect calls or calls
+	 to non-routines.  */
       if (info->state >= as_in_kernels_loop)
 	{
 	  tree fn = CALL_EXPR_FN (node), fn_decl = NULL_TREE;
@@ -3332,8 +3333,9 @@ annotate_loops_in_kernels_regions (tree *nodeptr, int *walk_subtrees,
 	    }
 	  if (fn_decl == NULL_TREE)
 	    do_not_annotate_loop_nest (info, as_invalid_call, node);
-	  else if (!lookup_attribute ("oacc function",
-				      DECL_ATTRIBUTES (fn_decl)))
+	  else if (!fndecl_built_in_p (fn_decl, BUILT_IN_NORMAL)
+		   && !lookup_attribute ("oacc function",
+					 DECL_ATTRIBUTES (fn_decl)))
 	    do_not_annotate_loop_nest (info, as_invalid_call, node);
 	}
       break;
diff --git a/gcc/fortran/ChangeLog.omp b/gcc/fortran/ChangeLog.omp
index a56ca22aefc..48277068b6b 100644
--- a/gcc/fortran/ChangeLog.omp
+++ b/gcc/fortran/ChangeLog.omp
@@ -1,3 +1,11 @@
+2020-08-22  Sandra Loosemore  <sandra@codesourcery.com>
+
+	Permit calls to Fortran intrinsics when annotating loops in
+	kernels regions.
+
+	* openmp.c (check_expr_for_invalid_calls): Check for intrinsic
+	functions.
+
 2020-08-19  Sandra Loosemore  <sandra@codesourcery.com>
 
 	Annotate inner loops in "acc kernels loop" directives (Fortran).
diff --git a/gcc/fortran/openmp.c b/gcc/fortran/openmp.c
index 01626e50c0e..dca2a782d73 100644
--- a/gcc/fortran/openmp.c
+++ b/gcc/fortran/openmp.c
@@ -7525,9 +7525,12 @@ check_expr_for_invalid_calls (gfc_expr **exprp, int *walk_subtrees,
   switch (expr->expr_type)
     {
     case EXPR_FUNCTION:
-      if (expr->value.function.esym
-	  && (expr->value.function.esym->attr.oacc_routine_lop
-	      != OACC_ROUTINE_LOP_NONE))
+      /* Permit calls to Fortran intrinsic functions and to routines
+	 with an explicitly declared parallelism level.  */
+      if (expr->value.function.isym
+	  || (expr->value.function.esym
+	      && (expr->value.function.esym->attr.oacc_routine_lop
+		  != OACC_ROUTINE_LOP_NONE)))
 	return 0;
       /* Else fall through.  */
 
diff --git a/gcc/testsuite/ChangeLog.omp b/gcc/testsuite/ChangeLog.omp
index d5c60a404fa..7672b8d76f8 100644
--- a/gcc/testsuite/ChangeLog.omp
+++ b/gcc/testsuite/ChangeLog.omp
@@ -1,3 +1,11 @@
+2020-08-22   Sandra Loosemore  <sandra@codesourcery.com>
+
+	Test cases for allowing calls to C/C++ builtins and Fortran
+	intrinsics in loops in kernels regions.
+
+	* c-c++-common/goacc/kernels-loop-annotation-20.c: New.
+	* gfortran.dg/goacc/kernels-loop-annotation-20.f95: New.
+
 2020-08-21  Tobias Burnus  <tobias@codesourcery.com>
 
 	* gfortran.dg/gomp/pr67500.f90: Change dg-warning to
diff --git a/gcc/testsuite/c-c++-common/goacc/kernels-loop-annotation-20.c b/gcc/testsuite/c-c++-common/goacc/kernels-loop-annotation-20.c
new file mode 100644
index 00000000000..5e3f0284571
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/goacc/kernels-loop-annotation-20.c
@@ -0,0 +1,23 @@
+/* { dg-additional-options "-fopenacc -fopenacc-kernels-annotate-loops" } */
+/* { dg-additional-options "-Wopenacc-kernels-annotate-loops" } */
+/* { dg-additional-options "-fdump-tree-original" } */
+/* { dg-do compile } */
+
+/* Test that calls to built-in functions don't inhibit kernels loop
+   annotation.  */
+
+void foo (int n, int *input, int *out1, int *out2)
+{
+#pragma acc kernels
+  {
+    int i;
+
+    for (i = 0; i < n; i++)
+      {
+	out1[i] = __builtin_clz (input[i]);
+	out2[i] = __builtin_popcount (input[i]);
+      }
+  }
+}
+
+/* { dg-final { scan-tree-dump-times "acc loop auto" 1 "original" } } */
diff --git a/gcc/testsuite/gfortran.dg/goacc/kernels-loop-annotation-20.f95 b/gcc/testsuite/gfortran.dg/goacc/kernels-loop-annotation-20.f95
new file mode 100644
index 00000000000..5169a0a1676
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/goacc/kernels-loop-annotation-20.f95
@@ -0,0 +1,26 @@
+! { dg-additional-options "-fopenacc -fopenacc-kernels-annotate-loops" }
+! { dg-additional-options "-Wopenacc-kernels-annotate-loops" }
+! { dg-additional-options "-fdump-tree-original" }
+! { dg-do compile }
+
+! Test that a loop with calls to intrinsics in the body can be annotated.
+
+subroutine f (n, input, out1, out2)
+  implicit none
+  integer :: n
+  integer, intent (in), dimension (n) :: input
+  integer, intent (out), dimension (n) :: out1, out2
+
+  integer :: i
+
+!$acc kernels
+
+  do i = 1, n
+      out1(i) = min (i, input(i))
+      out2(i) = not (input(i))
+  end do
+!$acc end kernels
+
+end subroutine f
+
+! { dg-final { scan-tree-dump-times "acc loop auto" 1 "original" } }