public inbox for gcc-patches@gcc.gnu.org
 help / color / mirror / Atom feed
From: Jakub Jelinek <jakub@redhat.com>
To: gcc-patches@gcc.gnu.org
Cc: Tobias Burnus <tobias@codesourcery.com>
Subject: [committed] openmp: Fix up handling of non-rectangular simd loops with pointer type iterators [PR106449]
Date: Fri, 29 Jul 2022 10:03:47 +0200	[thread overview]
Message-ID: <YuOUYzYWlO1Zicxr@tucnak> (raw)

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.

--- 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;
+}

	Jakub


             reply	other threads:[~2022-07-29  8:03 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-07-29  8:03 Jakub Jelinek [this message]
2022-07-29  9:48 ` [Patch] Add libgomp.c-c++-common/pr106449-2.c (was: [committed] openmp: Fix up handling of non-rectangular simd loops with pointer type iterators [PR106449]) Tobias Burnus
2022-07-29 10:34   ` Jakub Jelinek

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=YuOUYzYWlO1Zicxr@tucnak \
    --to=jakub@redhat.com \
    --cc=gcc-patches@gcc.gnu.org \
    --cc=tobias@codesourcery.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).