From 0df60f02c399a6bf65850ecd5719b25b3de6676f Mon Sep 17 00:00:00 2001
From: Harald Anlauf <anlauf@gmx.de>
Date: Wed, 10 Jan 2024 23:10:02 +0100
Subject: [PATCH] Fortran: annotations for DO CONCURRENT loops [PR113305]

gcc/fortran/ChangeLog:

	PR fortran/113305
	* gfortran.h: Add annotation controls to gfc_forall_iterator.
	* gfortran.texi: Document annotations IVDEP, UNROLL n, VECTOR,
	NOVECTOR as applied to DO CONCURRENT.
	* parse.cc (parse_do_block): Parse annotations IVDEP, UNROLL n,
	VECTOR, NOVECTOR as applied to DO CONCURRENT.  Apply UNROLL only to
	first loop control variable.
	* trans-stmt.cc (gfc_trans_forall_loop): Annotate loops with IVDEP,
	UNROLL n, VECTOR, NOVECTOR as needed for DO CONCURRENT.
	(gfc_trans_forall_1): Handle annotations IVDEP, UNROLL n, VECTOR,
	NOVECTOR.

gcc/testsuite/ChangeLog:

	PR fortran/113305
	* gfortran.dg/do_concurrent_7.f90: New test.
---
 gcc/fortran/gfortran.h                        |  4 +++
 gcc/fortran/gfortran.texi                     | 12 ++++++++
 gcc/fortran/parse.cc                          | 26 ++++++++++++++++-
 gcc/fortran/trans-stmt.cc                     | 29 ++++++++++++++++++-
 gcc/testsuite/gfortran.dg/do_concurrent_7.f90 | 26 +++++++++++++++++
 5 files changed, 95 insertions(+), 2 deletions(-)
 create mode 100644 gcc/testsuite/gfortran.dg/do_concurrent_7.f90

diff --git a/gcc/fortran/gfortran.h b/gcc/fortran/gfortran.h
index 82f388c05f8..88502c1e3f0 100644
--- a/gcc/fortran/gfortran.h
+++ b/gcc/fortran/gfortran.h
@@ -2926,6 +2926,10 @@ gfc_dt;
 typedef struct gfc_forall_iterator
 {
   gfc_expr *var, *start, *end, *stride;
+  unsigned short unroll;
+  bool ivdep;
+  bool vector;
+  bool novector;
   struct gfc_forall_iterator *next;
 }
 gfc_forall_iterator;
diff --git a/gcc/fortran/gfortran.texi b/gcc/fortran/gfortran.texi
index 5615fee2897..371666dcbb6 100644
--- a/gcc/fortran/gfortran.texi
+++ b/gcc/fortran/gfortran.texi
@@ -3262,6 +3262,9 @@ It must be placed immediately before a @code{DO} loop and applies only to the
 loop that follows.  N is an integer constant specifying the unrolling factor.
 The values of 0 and 1 block any unrolling of the loop.

+For @code{DO CONCURRENT} constructs the unrolling specification applies
+only to the first loop control variable.
+

 @node BUILTIN directive
 @subsection BUILTIN directive
@@ -3300,6 +3303,9 @@ whether a particular loop is vectorizable due to potential
 dependencies between iterations.  The purpose of the directive is to
 tell the compiler that vectorization is safe.

+For @code{DO CONCURRENT} constructs this annotation is implicit to all
+loop control variables.
+
 This directive is intended for annotation of existing code.  For new
 code it is recommended to consider OpenMP SIMD directives as potential
 alternative.
@@ -3316,6 +3322,9 @@ This directive tells the compiler to vectorize the following loop.  It
 must be placed immediately before a @code{DO} loop and applies only to
 the loop that follows.

+For @code{DO CONCURRENT} constructs this annotation applies to all loops
+specified in the concurrent header.
+

 @node NOVECTOR directive
 @subsection NOVECTOR directive
@@ -3328,6 +3337,9 @@ This directive tells the compiler to not vectorize the following loop.
 It must be placed immediately before a @code{DO} loop and applies only
 to the loop that follows.

+For @code{DO CONCURRENT} constructs this annotation applies to all loops
+specified in the concurrent header.
+

 @node Non-Fortran Main Program
 @section Non-Fortran Main Program
diff --git a/gcc/fortran/parse.cc b/gcc/fortran/parse.cc
index d8b38cfb5ac..f41cc7d3510 100644
--- a/gcc/fortran/parse.cc
+++ b/gcc/fortran/parse.cc
@@ -5307,7 +5307,31 @@ parse_do_block (void)
   do_op = new_st.op;
   s.ext.end_do_label = new_st.label1;

-  if (new_st.ext.iterator != NULL)
+  if (do_op == EXEC_DO_CONCURRENT)
+    {
+      gfc_forall_iterator *fa;
+      for (fa = new_st.ext.forall_iterator; fa; fa = fa->next)
+	{
+	  /* Apply unroll only to innermost loop (first control
+	     variable).  */
+	  if (directive_unroll != -1)
+	    {
+	      fa->unroll = directive_unroll;
+	      directive_unroll = -1;
+	    }
+	  if (directive_ivdep)
+	    fa->ivdep = directive_ivdep;
+	  if (directive_vector)
+	    fa->vector = directive_vector;
+	  if (directive_novector)
+	    fa->novector = directive_novector;
+	}
+      directive_ivdep = false;
+      directive_vector = false;
+      directive_novector = false;
+      stree = NULL;
+    }
+  else if (new_st.ext.iterator != NULL)
     {
       stree = new_st.ext.iterator->var->symtree;
       if (directive_unroll != -1)
diff --git a/gcc/fortran/trans-stmt.cc b/gcc/fortran/trans-stmt.cc
index a718dce237f..59a9cf99f9b 100644
--- a/gcc/fortran/trans-stmt.cc
+++ b/gcc/fortran/trans-stmt.cc
@@ -41,6 +41,10 @@ typedef struct iter_info
   tree start;
   tree end;
   tree step;
+  unsigned short unroll;
+  bool ivdep;
+  bool vector;
+  bool novector;
   struct iter_info *next;
 }
 iter_info;
@@ -4117,12 +4121,30 @@ gfc_trans_forall_loop (forall_info *forall_tmp, tree body,

       /* PR 83064 means that we cannot use annot_expr_parallel_kind until
        the autoparallelizer can handle this.  */
-      if (forall_tmp->do_concurrent)
+      if (forall_tmp->do_concurrent || iter->ivdep)
 	cond = build3 (ANNOTATE_EXPR, TREE_TYPE (cond), cond,
 		       build_int_cst (integer_type_node,
 				      annot_expr_ivdep_kind),
 		       integer_zero_node);

+      if (iter->unroll && cond != error_mark_node)
+	cond = build3 (ANNOTATE_EXPR, TREE_TYPE (cond), cond,
+		       build_int_cst (integer_type_node,
+				      annot_expr_unroll_kind),
+		       build_int_cst (integer_type_node, iter->unroll));
+
+      if (iter->vector && cond != error_mark_node)
+	cond = build3 (ANNOTATE_EXPR, TREE_TYPE (cond), cond,
+		       build_int_cst (integer_type_node,
+				      annot_expr_vector_kind),
+		       integer_zero_node);
+
+      if (iter->novector && cond != error_mark_node)
+	cond = build3 (ANNOTATE_EXPR, TREE_TYPE (cond), cond,
+		       build_int_cst (integer_type_node,
+				      annot_expr_no_vector_kind),
+		       integer_zero_node);
+
       tmp = build1_v (GOTO_EXPR, exit_label);
       tmp = fold_build3_loc (input_location, COND_EXPR, void_type_node,
 			     cond, tmp, build_empty_stmt (input_location));
@@ -5090,6 +5112,11 @@ gfc_trans_forall_1 (gfc_code * code, forall_info * nested_forall_info)
       gfc_add_block_to_block (&block, &se.pre);
       step[n] = se.expr;

+      this_forall->unroll = fa->unroll;
+      this_forall->ivdep = fa->ivdep;
+      this_forall->vector = fa->vector;
+      this_forall->novector = fa->novector;
+
       /* Set the NEXT field of this_forall to NULL.  */
       this_forall->next = NULL;
       /* Link this_forall to the info construct.  */
diff --git a/gcc/testsuite/gfortran.dg/do_concurrent_7.f90 b/gcc/testsuite/gfortran.dg/do_concurrent_7.f90
new file mode 100644
index 00000000000..604f6712d05
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/do_concurrent_7.f90
@@ -0,0 +1,26 @@
+! { dg-do compile }
+! { dg-additional-options "-fdump-tree-original" }
+! PR fortran/113305
+
+program dc
+  implicit none
+  real :: a(12), b(12), c(16,8), d(16,8)
+  integer :: i, j
+  call random_number(b)
+!GCC$ ivdep
+!GCC$ vector
+  do concurrent (i=1:12)
+     a(i) = 2*b(i)
+  end do
+  c = b(1)
+  d = a(2)
+!GCC$ novector
+!GCC$ unroll 4
+  do concurrent (i=1:16:2,j=1:8:2)
+     d(i,j) = 3*c(i,j)
+  end do
+end program
+
+! { dg-final { scan-tree-dump "ANNOTATE_EXPR .* ivdep>, vector" "original" } }
+! { dg-final { scan-tree-dump "ANNOTATE_EXPR .* ivdep>, no-vector" "original" } }
+! { dg-final { scan-tree-dump "ANNOTATE_EXPR .* ivdep>, unroll 4>, no-vector" "original" } }
--
2.35.3

