[committed] openmp - Fix up && and || reductions [PR94366]

Jakub Jelinek jakub@redhat.com
Thu Jul 1 07:21:44 GMT 2021


Hi!

As the testcase shows, the special treatment of && and || reduction combiners
where we expand them as omp_out = (omp_out != 0) && (omp_in != 0) (or with ||)
is not needed just for &&/|| on floating point or complex types, but for all
&&/|| reductions - when expanded as omp_out = omp_out && omp_in (not in C but
GENERIC) it is actually gimplified into NOP_EXPRs to bool from both operands,
which turns non-zero values multiple of 2 into 0 rather than 1.

This patch just treats all &&/|| the same and furthermore uses bool type
instead of int for the comparisons.

Bootstrapped/regtested on x86_64-linux and i686-linux, committed to trunk.

2021-07-01  Jakub Jelinek  <jakub@redhat.com>

	PR middle-end/94366
gcc/
	* omp-low.c (lower_rec_input_clauses): Rename is_fp_and_or to
	is_truth_op, set it for TRUTH_*IF_EXPR regardless of new_var's type,
	use boolean_type_node instead of integer_type_node as NE_EXPR type.
	(lower_reduction_clauses): Likewise.
libgomp/
	* testsuite/libgomp.c-c++-common/pr94366.c: New test.

--- gcc/omp-low.c.jj	2021-06-25 10:36:22.235019049 +0200
+++ gcc/omp-low.c	2021-06-30 12:08:03.177601386 +0200
@@ -6505,11 +6505,8 @@ lower_rec_input_clauses (tree clauses, g
 		  if (code == MINUS_EXPR)
 		    code = PLUS_EXPR;
 
-		  /* C/C++ permits FP/complex with || and &&.  */
-		  bool is_fp_and_or
-		    = ((code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
-		       && (FLOAT_TYPE_P (TREE_TYPE (new_var))
-			   || TREE_CODE (TREE_TYPE (new_var)) == COMPLEX_TYPE));
+		  bool is_truth_op
+		    = (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR);
 		  tree new_vard = new_var;
 		  if (is_simd && omp_is_reference (var))
 		    {
@@ -6560,17 +6557,18 @@ lower_rec_input_clauses (tree clauses, g
 			}
 		      tree ivar2 = ivar;
 		      tree ref2 = ref;
-		      if (is_fp_and_or)
+		      if (is_truth_op)
 			{
 			  tree zero = build_zero_cst (TREE_TYPE (ivar));
 			  ivar2 = fold_build2_loc (clause_loc, NE_EXPR,
-						   integer_type_node, ivar,
+						   boolean_type_node, ivar,
 						   zero);
 			  ref2 = fold_build2_loc (clause_loc, NE_EXPR,
-						  integer_type_node, ref, zero);
+						  boolean_type_node, ref,
+						  zero);
 			}
 		      x = build2 (code, TREE_TYPE (ref), ref2, ivar2);
-		      if (is_fp_and_or)
+		      if (is_truth_op)
 			x = fold_convert (TREE_TYPE (ref), x);
 		      ref = build_outer_var_ref (var, ctx);
 		      gimplify_assign (ref, x, &llist[1]);
@@ -6592,19 +6590,19 @@ lower_rec_input_clauses (tree clauses, g
 			  tree ref = build_outer_var_ref (var, ctx);
 			  tree new_var2 = new_var;
 			  tree ref2 = ref;
-			  if (is_fp_and_or)
+			  if (is_truth_op)
 			    {
 			      tree zero = build_zero_cst (TREE_TYPE (new_var));
 			      new_var2
 				= fold_build2_loc (clause_loc, NE_EXPR,
-						   integer_type_node, new_var,
+						   boolean_type_node, new_var,
 						   zero);
 			      ref2 = fold_build2_loc (clause_loc, NE_EXPR,
-						      integer_type_node, ref,
+						      boolean_type_node, ref,
 						      zero);
 			    }
 			  x = build2 (code, TREE_TYPE (ref2), ref2, new_var2);
-			  if (is_fp_and_or)
+			  if (is_truth_op)
 			    x = fold_convert (TREE_TYPE (new_var), x);
 			  ref = build_outer_var_ref (var, ctx);
 			  gimplify_assign (ref, x, dlist);
@@ -7548,12 +7546,7 @@ lower_reduction_clauses (tree clauses, g
       if (code == MINUS_EXPR)
         code = PLUS_EXPR;
 
-      /* C/C++ permits FP/complex with || and &&.  */
-      bool is_fp_and_or = ((code == TRUTH_ANDIF_EXPR
-			    || code == TRUTH_ORIF_EXPR)
-			   && (FLOAT_TYPE_P (TREE_TYPE (new_var))
-			       || (TREE_CODE (TREE_TYPE (new_var))
-				   == COMPLEX_TYPE)));
+      bool is_truth_op = (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR);
       if (count == 1)
 	{
 	  tree addr = build_fold_addr_expr_loc (clause_loc, ref);
@@ -7562,17 +7555,17 @@ lower_reduction_clauses (tree clauses, g
 	  ref = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (addr)), addr);
 	  tree new_var2 = new_var;
 	  tree ref2 = ref;
-	  if (is_fp_and_or)
+	  if (is_truth_op)
 	    {
 	      tree zero = build_zero_cst (TREE_TYPE (new_var));
 	      new_var2 = fold_build2_loc (clause_loc, NE_EXPR,
-					  integer_type_node, new_var, zero);
-	      ref2 = fold_build2_loc (clause_loc, NE_EXPR, integer_type_node,
+					  boolean_type_node, new_var, zero);
+	      ref2 = fold_build2_loc (clause_loc, NE_EXPR, boolean_type_node,
 				      ref, zero);
 	    }
 	  x = fold_build2_loc (clause_loc, code, TREE_TYPE (new_var2), ref2,
 			       new_var2);
-	  if (is_fp_and_or)
+	  if (is_truth_op)
 	    x = fold_convert (TREE_TYPE (new_var), x);
 	  x = build2 (OMP_ATOMIC, void_type_node, addr, x);
 	  OMP_ATOMIC_MEMORY_ORDER (x) = OMP_MEMORY_ORDER_RELAXED;
@@ -7680,16 +7673,16 @@ lower_reduction_clauses (tree clauses, g
 	    {
 	      tree out2 = out;
 	      tree priv2 = priv;
-	      if (is_fp_and_or)
+	      if (is_truth_op)
 		{
 		  tree zero = build_zero_cst (TREE_TYPE (out));
 		  out2 = fold_build2_loc (clause_loc, NE_EXPR,
-					  integer_type_node, out, zero);
+					  boolean_type_node, out, zero);
 		  priv2 = fold_build2_loc (clause_loc, NE_EXPR,
-					   integer_type_node, priv, zero);
+					   boolean_type_node, priv, zero);
 		}
 	      x = build2 (code, TREE_TYPE (out2), out2, priv2);
-	      if (is_fp_and_or)
+	      if (is_truth_op)
 		x = fold_convert (TREE_TYPE (out), x);
 	      out = unshare_expr (out);
 	      gimplify_assign (out, x, &sub_seq);
@@ -7726,16 +7719,16 @@ lower_reduction_clauses (tree clauses, g
 	{
 	  tree new_var2 = new_var;
 	  tree ref2 = ref;
-	  if (is_fp_and_or)
+	  if (is_truth_op)
 	    {
 	      tree zero = build_zero_cst (TREE_TYPE (new_var));
 	      new_var2 = fold_build2_loc (clause_loc, NE_EXPR,
-					  integer_type_node, new_var, zero);
-	      ref2 = fold_build2_loc (clause_loc, NE_EXPR, integer_type_node,
+					  boolean_type_node, new_var, zero);
+	      ref2 = fold_build2_loc (clause_loc, NE_EXPR, boolean_type_node,
 				      ref, zero);
 	    }
 	  x = build2 (code, TREE_TYPE (ref), ref2, new_var2);
-	  if (is_fp_and_or)
+	  if (is_truth_op)
 	    x = fold_convert (TREE_TYPE (new_var), x);
 	  ref = build_outer_var_ref (var, ctx);
 	  gimplify_assign (ref, x, &sub_seq);
--- libgomp/testsuite/libgomp.c-c++-common/pr94366.c.jj	2021-06-30 12:28:02.921918443 +0200
+++ libgomp/testsuite/libgomp.c-c++-common/pr94366.c	2021-06-30 12:27:42.838195583 +0200
@@ -0,0 +1,17 @@
+/* PR middle-end/94366 */
+
+int
+main ()
+{
+  int a = 2;
+  #pragma omp parallel reduction(&& : a)
+    a = a && 1;
+  if (!a)
+    __builtin_abort ();
+  a = 4;
+  #pragma omp parallel reduction(|| : a)
+    a = a || 0;
+  if (!a)
+    __builtin_abort ();
+  return 0;
+}


	Jakub



More information about the Gcc-patches mailing list