diff mbox series

[committed] openmp: Fix up handling of non-rectangular simd loops with pointer type iterators [PR106449]

Message ID YuOUYzYWlO1Zicxr@tucnak
State New, archived
Headers
Series [committed] openmp: Fix up handling of non-rectangular simd loops with pointer type iterators [PR106449] |

Commit Message

Jakub Jelinek July 29, 2022, 8:03 a.m. UTC 
  Hi!

There were 2 issues visible on this new testcase, one that we didn't have
special POINTER_TYPE_P handling in a few spots of expand_omp_simd - for
pointers we need to use POINTER_PLUS_EXPR and need to have the non-pointer
part in sizetype, for non-rectangular loop on the other side we can rely on
multiplication factor 1, pointers can't be multiplied, without those changes
we'd ICE.  The other issue was that we put n2 expression directly into a
comparison in a condition and regimplified that, for the &a[512] case that
and with gimplification being destructed that unfortunately meant modification
of original fd->loops[?].n2.  Fixed by unsharing the expression.  This was
causing a runtime failure on the testcase.

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

2022-07-29  Jakub Jelinek  <jakub@redhat.com>

	PR middle-end/106449
	* omp-expand.cc (expand_omp_simd): Fix up handling of pointer
	iterators in non-rectangular simd loops.  Unshare fd->loops[i].n2
	or n2 before regimplifying it inside of a condition.

	* testsuite/libgomp.c-c++-common/pr106449.c: New test.


	Jakub
diff mbox series

Patch

--- gcc/omp-expand.cc.jj	2022-06-28 13:03:30.930689700 +0200
+++ gcc/omp-expand.cc	2022-07-28 10:47:03.138939297 +0200
@@ -6714,7 +6696,7 @@  expand_omp_simd (struct omp_region *regi
       if (fd->loops[i].m2)
 	t = n2v = create_tmp_var (itype);
       else
-	t = fold_convert (itype, fd->loops[i].n2);
+	t = fold_convert (itype, unshare_expr (fd->loops[i].n2));
       t = force_gimple_operand_gsi (&gsi, t, true, NULL_TREE,
 				    false, GSI_CONTINUE_LINKING);
       tree v = fd->loops[i].v;
@@ -6728,7 +6710,7 @@  expand_omp_simd (struct omp_region *regi
       if (fd->collapse > 1 && !broken_loop)
 	t = n2var;
       else
-	t = fold_convert (type, n2);
+	t = fold_convert (type, unshare_expr (n2));
       t = force_gimple_operand_gsi (&gsi, t, true, NULL_TREE,
 				    false, GSI_CONTINUE_LINKING);
       tree v = fd->loop.v;
@@ -6840,7 +6819,7 @@  expand_omp_simd (struct omp_region *regi
 	  if (fd->loops[i].m2)
 	    t = nextn2v = create_tmp_var (itype);
 	  else
-	    t = fold_convert (itype, fd->loops[i].n2);
+	    t = fold_convert (itype, unshare_expr (fd->loops[i].n2));
 	  t = force_gimple_operand_gsi (&gsi, t, true, NULL_TREE,
 					false, GSI_CONTINUE_LINKING);
 	  tree v = fd->loops[i].v;
@@ -6870,17 +6849,25 @@  expand_omp_simd (struct omp_region *regi
 	  ne->probability = e->probability.invert ();
 
 	  gsi = gsi_after_labels (init_bb);
-	  t = fold_convert (TREE_TYPE (fd->loops[i + 1].v),
-			    fd->loops[i + 1].n1);
 	  if (fd->loops[i + 1].m1)
 	    {
-	      tree t2 = fold_convert (TREE_TYPE (t),
+	      tree t2 = fold_convert (TREE_TYPE (fd->loops[i + 1].v),
 				      fd->loops[i + 1
 						- fd->loops[i + 1].outer].v);
-	      tree t3 = fold_convert (TREE_TYPE (t), fd->loops[i + 1].m1);
-	      t2 = fold_build2 (MULT_EXPR, TREE_TYPE (t), t2, t3);
-	      t = fold_build2 (PLUS_EXPR, TREE_TYPE (t), t, t2);
+	      if (POINTER_TYPE_P (TREE_TYPE (t2)))
+		t = fold_build_pointer_plus (t2, fd->loops[i + 1].n1);
+	      else
+		{
+		  t = fold_convert (TREE_TYPE (fd->loops[i + 1].v),
+				    fd->loops[i + 1].n1);
+		  tree t3 = fold_convert (TREE_TYPE (t), fd->loops[i + 1].m1);
+		  t2 = fold_build2 (MULT_EXPR, TREE_TYPE (t), t2, t3);
+		  t = fold_build2 (PLUS_EXPR, TREE_TYPE (t), t, t2);
+		}
 	    }
+	  else
+	    t = fold_convert (TREE_TYPE (fd->loops[i + 1].v),
+			      fd->loops[i + 1].n1);
 	  expand_omp_build_assign (&gsi, fd->loops[i + 1].v, t);
 	  if (fd->loops[i + 1].m2)
 	    {
@@ -6889,14 +6876,19 @@  expand_omp_simd (struct omp_region *regi
 		  gcc_assert (n2v == NULL_TREE);
 		  n2v = create_tmp_var (TREE_TYPE (fd->loops[i + 1].v));
 		}
-	      t = fold_convert (TREE_TYPE (fd->loops[i + 1].v),
-				fd->loops[i + 1].n2);
-	      tree t2 = fold_convert (TREE_TYPE (t),
+	      tree t2 = fold_convert (TREE_TYPE (fd->loops[i + 1].v),
 				      fd->loops[i + 1
 						- fd->loops[i + 1].outer].v);
-	      tree t3 = fold_convert (TREE_TYPE (t), fd->loops[i + 1].m2);
-	      t2 = fold_build2 (MULT_EXPR, TREE_TYPE (t), t2, t3);
-	      t = fold_build2 (PLUS_EXPR, TREE_TYPE (t), t, t2);
+	      if (POINTER_TYPE_P (TREE_TYPE (t2)))
+		t = fold_build_pointer_plus (t2, fd->loops[i + 1].n2);
+	      else
+		{
+		  t = fold_convert (TREE_TYPE (fd->loops[i + 1].v),
+				    fd->loops[i + 1].n2);
+		  tree t3 = fold_convert (TREE_TYPE (t), fd->loops[i + 1].m2);
+		  t2 = fold_build2 (MULT_EXPR, TREE_TYPE (t), t2, t3);
+		  t = fold_build2 (PLUS_EXPR, TREE_TYPE (t), t, t2);
+		}
 	      expand_omp_build_assign (&gsi, n2v, t);
 	    }
 	  if (i + 2 == fd->collapse && n2var)
@@ -6912,17 +6904,25 @@  expand_omp_simd (struct omp_region *regi
 	      tree t2 = fold_build2 (MINUS_EXPR, type, n2, fd->loop.v);
 	      if (fd->loops[i + 1].m1 || fd->loops[i + 1].m2)
 		{
+		  tree itype = TREE_TYPE (fd->loops[i].v);
+		  if (POINTER_TYPE_P (itype))
+		    itype = signed_type_for (itype);
 		  t = build_int_cst (itype, (fd->loops[i + 1].cond_code
 					     == LT_EXPR ? -1 : 1));
 		  t = fold_build2 (PLUS_EXPR, itype,
 				   fold_convert (itype,
 						 fd->loops[i + 1].step), t);
-		  if (fd->loops[i + 1].m2)
-		    t = fold_build2 (PLUS_EXPR, itype, t, n2v);
-		  else
+		  if (fd->loops[i + 1].m2 == NULL_TREE)
 		    t = fold_build2 (PLUS_EXPR, itype, t,
 				     fold_convert (itype,
 						   fd->loops[i + 1].n2));
+		  else if (POINTER_TYPE_P (TREE_TYPE (n2v)))
+		    {
+		      t = fold_build_pointer_plus (n2v, t);
+		      t = fold_convert (itype, t);
+		    }
+		  else
+		    t = fold_build2 (PLUS_EXPR, itype, t, n2v);
 		  t = fold_build2 (MINUS_EXPR, itype, t,
 				   fold_convert (itype, fd->loops[i + 1].v));
 		  tree step = fold_convert (itype, fd->loops[i + 1].step);
--- libgomp/testsuite/libgomp.c-c++-common/pr106449.c.jj	2022-07-28 11:35:50.276558893 +0200
+++ libgomp/testsuite/libgomp.c-c++-common/pr106449.c	2022-07-28 12:03:27.495268905 +0200
@@ -0,0 +1,62 @@ 
+/* PR middle-end/106449 */
+/* { dg-do run } */
+
+void
+foo (void)
+{
+  int a[1024], *b[65536];
+  int *p, *q, **r = &b[0], i;
+  #pragma omp simd collapse(2) linear(r : 2)
+  for (p = &a[0]; p < &a[512]; p++)
+    for (q = p + 64; q < p + 128; q++)
+      {
+        *r++ = p;
+        *r++ = q;
+      }
+  for (i = 0; i < 32768; i++)
+    if (b[2 * i] != &a[i / 64] || b[2 * i + 1] != &a[(i / 64) + 64 + (i % 64)])
+      __builtin_abort ();
+}
+
+void
+bar (int n, int m)
+{
+  int a[1024], *b[65536];
+  int *p, *q, **r = &b[0], i;
+  #pragma omp parallel for simd collapse(2) linear(r : 2)
+  for (p = &a[0]; p < &a[512]; p++)
+    for (q = p + n; q < p + m; q++)
+      {
+        *r++ = p;
+        *r++ = q;
+      }
+  for (i = 0; i < 32768; i++)
+    if (b[2 * i] != &a[i / 64] || b[2 * i + 1] != &a[(i / 64) + 64 + (i % 64)])
+      __builtin_abort ();
+}
+
+void
+baz (int n, int m)
+{
+  int a[1024], *b[8192];
+  int *p, *q, **r = &b[0], i;
+  #pragma omp parallel for simd collapse(2) linear(r : 2)
+  for (p = &a[0]; p < &a[512]; p += 4)
+    for (q = p + n; q < p + m; q += 2)
+      {
+        *r++ = p;
+        *r++ = q;
+      }
+  for (i = 0; i < 4096; i++)
+    if (b[2 * i] != &a[(i / 32) * 4] || b[2 * i + 1] != &a[(i / 32) * 4 + 64 + (i % 32) * 2])
+      __builtin_abort ();
+}
+
+int
+main ()
+{
+  foo ();
+  bar (64, 128);
+  baz (64, 128);
+  return 0;
+}