openmp: Allow non-rectangular loops with pointer iterators

This patch handles pointer iterators for non-rectangular loops.  They are
more limited than integral iterators of non-rectangular loops, in particular
only var-outer, var-outer + a2, a2 + var-outer or var-outer - a2 can appear
in lb or ub where a2 is some integral loop invariant expression, so no e.g.
multiplication etc.

2021-10-27  Jakub Jelinek  <jakub@redhat.com>

gcc/
	* omp-expand.c (expand_omp_for_init_counts): Handle non-rectangular
	iterators with pointer types.
	(expand_omp_for_init_vars, extract_omp_for_update_vars): Likewise.
gcc/c-family/
	* c-omp.c (c_omp_check_loop_iv_r): Don't clear 3rd bit for
	POINTER_PLUS_EXPR.
	(c_omp_check_nonrect_loop_iv): Handle POINTER_PLUS_EXPR.
	(c_omp_check_loop_iv): Set kind even if the iterator is non-integral.
gcc/testsuite/
	* c-c++-common/gomp/loop-8.c: New test.
	* c-c++-common/gomp/loop-9.c: New test.
libgomp/
	* testsuite/libgomp.c/loop-26.c: New test.
	* testsuite/libgomp.c/loop-27.c: New test.

1 files changed, 180 insertions, 0 deletions

diff --git a/libgomp/testsuite/libgomp.c/loop-27.c b/libgomp/testsuite/libgomp.c/loop-27.c
new file mode 100644
index 0000000..3353b87
--- /dev/null
+++ b/libgomp/testsuite/libgomp.c/loop-27.c
@@ -0,0 +1,180 @@
+/* { dg-do run } */
+
+extern void abort (void);
+
+int x;
+short *i, *j;
+int ii, jj;
+short *volatile a;
+short *volatile b;
+volatile int c, e, f, g;
+short *volatile d;
+int k[11][20];
+short v[84];
+
+int
+main ()
+{
+  int niters;
+  for (ii = 1; ii <= 10; ii++)
+    for (jj = 1; jj <= ii + 5; jj++)
+      k[ii][jj] = 1;
+  a = &v[42 + 1]; b = &v[42 + 11]; c = 1; d = &v[42 + 1]; e = 6; f = 1;
+  niters = 0; i = &v[0]; j = &v[0]; x = -100;
+  #pragma omp parallel for collapse(2) lastprivate (i, j, x) reduction(+:niters)
+  for (i = &v[42 + 1]; i <= &v[42 + 10]; i++)
+    for (j = &v[42 + 1]; j <= i + 5; j++)
+      {
+	if (i < &v[42 + 1] || i > &v[42 + 10] || j < &v[42 + 1] || j > i + 5 || k[i - &v[42]][j - &v[42]] != 1)
+	  abort ();
+	k[i - &v[42]][j - &v[42]]++;
+	x = (i - &v[42]) * 1024 + ((j - &v[42]) & 1023);
+	niters++;
+      }
+  if (i != &v[42 + 11] || j != &v[42 + 16] || x != 10255 || niters != 105)
+    abort ();
+  niters = 0; i = &v[0]; j = &v[0]; x = -100;
+  #pragma omp parallel for collapse(2) lastprivate (i, j, x) reduction(+:niters)
+  for (i = a; i < b; i += c)
+    for (j = d; j < e + i; j += f)
+      {
+	if (i < &v[42 + 1] || i > &v[42 + 10] || j < &v[42 + 1] || j > i + 5 || k[i - &v[42]][j - &v[42]] != 2)
+	  abort ();
+	k[i - &v[42]][j - &v[42]]++;
+	x = (i - &v[42]) * 1024 + ((j - &v[42]) & 1023);
+	niters++;
+      }
+  if (i != &v[42 + 11] || j != &v[42 + 16] || x != 10255 || niters != 105)
+    abort ();
+  for (ii = 1; ii <= 10; ii++)
+    for (jj = 1; jj <= ii + 5; jj++)
+      if (k[ii][jj] == 3)
+	k[ii][jj] = 0;
+      else
+	abort ();
+  for (ii = 0; ii < 11; ii++)
+    for (jj = 0; jj < 20; jj++)
+      if (k[ii][jj] != 0)
+	abort ();
+  for (ii = 0; ii < 10; ii++)
+    for (jj = 0; jj < ii; jj++)
+      k[ii][jj] = 1;
+  a = &v[42]; b = &v[42 + 10]; c = 1; d = &v[42]; e = 0; f = 1;
+  niters = 0; i = &v[0]; j = &v[0]; x = -100;
+  #pragma omp parallel for collapse(2) lastprivate (i, j, x) reduction(+:niters)
+  for (i = &v[42]; i < &v[42 + 10]; i++)
+    for (j = &v[42]; j < i; j++)
+      {
+	if (i < &v[42] || i >= &v[42 + 10] || j < &v[42] || j >= i || k[i - &v[42]][j - &v[42]] != 1)
+	  abort ();
+	k[i - &v[42]][j - &v[42]]++;
+	x = (i - &v[42]) * 1024 + ((j - &v[42]) & 1023);
+	niters++;
+      }
+  if (i != &v[42 + 10] || j != &v[42 + 9] || x != 9224 || niters != 45)
+    abort ();
+  niters = 0; i = &v[0]; j = &v[0]; x = -100;
+  #pragma omp parallel for collapse(2) lastprivate (i, j, x) reduction(+:niters)
+  for (i = a; i < b; i += c)
+    for (j = d; j < i - e; j += f)
+      {
+	if (i < &v[42] || i >= &v[42 + 10] || j < &v[42] || j >= i || k[i - &v[42]][j - &v[42]] != 2)
+	  abort ();
+	k[i - &v[42]][j - &v[42]]++;
+	x = (i - &v[42]) * 1024 + ((j - &v[42]) & 1023);
+	niters++;
+      }
+  if (i != &v[42 + 10] || j != &v[42 + 9] || x != 9224 || niters != 45)
+    abort ();
+  for (ii = 0; ii < 10; ii++)
+    for (jj = 0; jj < ii; jj++)
+      if (k[ii][jj] == 3)
+	k[ii][jj] = 0;
+      else
+	abort ();
+  for (ii = 0; ii < 11; ii++)
+    for (jj = 0; jj < 20; jj++)
+      if (k[ii][jj] != 0)
+	abort ();
+  for (ii = 0; ii < 10; ii++)
+    for (jj = ii + 1; jj < ii + 4; jj++)
+      k[ii][jj] = 1;
+  a = &v[42]; b = &v[42 + 10]; c = 1; e = 1; f = 1; g = -4;
+  niters = 0; i = &v[0]; j = &v[0]; x = -100;
+  #pragma omp parallel for collapse(2) lastprivate (i, j, x) reduction(+:niters)
+  for (i = &v[42]; i < &v[42 + 10]; i++)
+    for (j = i + 1; j < i + 4; j++)
+      {
+	if (i < &v[42] || i >= &v[42 + 10] || j < i + 1 || j >= i + 4 || k[i - &v[42]][j - &v[42]] != 1)
+	  abort ();
+	k[i - &v[42]][j - &v[42]]++;
+	x = (i - &v[42]) * 1024 + ((j - &v[42]) & 1023);
+	niters++;
+      }
+  if (i != &v[42 + 10] || j != &v[42 + 13] || x != 9228 || niters != 30)
+    abort ();
+  niters = 0; i = &v[0]; j = &v[0]; x = -100;
+  #pragma omp parallel for collapse(2) lastprivate (i, j, x) reduction(+:niters)
+  for (i = a; i < b; i += c)
+    for (j = i + e; j < i - g; j += f)
+      {
+	if (i < &v[42] || i >= &v[42 + 10] || j < i + 1 || j >= i + 4 || k[i - &v[42]][j - &v[42]] != 2)
+	  abort ();
+	k[i - &v[42]][j - &v[42]]++;
+	x = (i - &v[42]) * 1024 + ((j - &v[42]) & 1023);
+	niters++;
+      }
+  if (i != &v[42 + 10] || j != &v[42 + 13] || x != 9228 || niters != 30)
+    abort ();
+  for (ii = 0; ii < 10; ii++)
+    for (jj = ii + 1; jj < ii + 4; jj++)
+      if (k[ii][jj] == 3)
+	k[ii][jj] = 0;
+      else
+	abort ();
+  for (ii = 0; ii < 11; ii++)
+    for (jj = 0; jj < 20; jj++)
+      if (k[ii][jj] != 0)
+	abort ();
+  for (ii = 1; ii < 10; ii += 2)
+    for (jj = 1; jj < ii + 1; jj++)
+      k[ii][jj] = 1;
+  a = &v[42 + 1]; b = &v[42 + 10]; c = 2; d = &v[42 + 1]; e = 1; f = 1;
+  niters = 0; i = &v[0]; j = &v[0]; x = -100;
+  #pragma omp parallel for collapse(2) lastprivate (i, j, x) reduction(+:niters)
+  for (i = &v[42 + 1]; i < &v[42 + 10]; i += 2)
+    for (j = &v[42 + 1]; j < i + 1; j++)
+      {
+	if (i < &v[42 + 1] || i >= &v[42 + 10] || j < &v[42 + 1] || j >= i + 1 || k[i - &v[42]][j - &v[42]] != 1)
+	  abort ();
+	k[i - &v[42]][j - &v[42]]++;
+	x = (i - &v[42]) * 1024 + ((j - &v[42]) & 1023);
+	niters++;
+      }
+  if (i != &v[42 + 11] || j != &v[42 + 10] || x != 9225 || niters != 25)
+    abort ();
+  niters = 0; i = &v[0]; j = &v[0]; x = -100;
+  #pragma omp parallel for collapse(2) lastprivate (i, j, x) reduction(+:niters)
+  for (i = a; i < b; i += c)
+    for (j = d; j < i + e; j += f)
+      {
+	if (i < &v[42 + 1] || i >= &v[42 + 10] || j < &v[42 + 1] || j >= i + 1 || k[i - &v[42]][j - &v[42]] != 2)
+	  abort ();
+	k[i - &v[42]][j - &v[42]]++;
+	x = (i - &v[42]) * 1024 + ((j - &v[42]) & 1023);
+	niters++;
+      }
+  if (i != &v[42 + 11] || j != &v[42 + 10] || x != 9225 || niters != 25)
+    abort ();
+  for (ii = 1; ii < 10; ii += 2)
+    for (jj = 1; jj < ii + 1; jj++)
+      if (k[ii][jj] == 3)
+	k[ii][jj] = 0;
+      else
+	abort ();
+  for (ii = 0; ii < 11; ii++)
+    for (jj = 0; jj < 20; jj++)
+      if (k[ii][jj] != 0)
+	abort ();
+  return 0;
+}