Handle mix/max pointer reductions in parloops

2015-08-27  Tom de Vries  <tom@codesourcery.com>

	PR tree-optimization/46193
	* omp-low.c (omp_reduction_init): Handle pointer type for min or max
	clause.

	* gcc.dg/autopar/pr46193.c: New test.

	* testsuite/libgomp.c/pr46193.c: New test.
---
 gcc/omp-low.c                          | 12 ++++++
 gcc/testsuite/gcc.dg/autopar/pr46193.c | 38 +++++++++++++++++++
 libgomp/testsuite/libgomp.c/pr46193.c  | 67 ++++++++++++++++++++++++++++++++++
 3 files changed, 117 insertions(+)
 create mode 100644 gcc/testsuite/gcc.dg/autopar/pr46193.c
 create mode 100644 libgomp/testsuite/libgomp.c/pr46193.c

diff --git a/gcc/omp-low.c b/gcc/omp-low.c
index 19f34ec..aa2a598 100644
--- a/gcc/omp-low.c
+++ b/gcc/omp-low.c
@@ -3412,6 +3412,12 @@ omp_reduction_init (tree clause, tree type)
 	    real_maxval (&min, 1, TYPE_MODE (type));
 	  return build_real (type, min);
 	}
+      else if (POINTER_TYPE_P (type))
+	{
+	  wide_int min
+	    = wi::min_value (TYPE_PRECISION (type), TYPE_SIGN (type));
+	  return wide_int_to_tree (type, min);
+	}
       else
 	{
 	  gcc_assert (INTEGRAL_TYPE_P (type));
@@ -3428,6 +3434,12 @@ omp_reduction_init (tree clause, tree type)
 	    real_maxval (&max, 0, TYPE_MODE (type));
 	  return build_real (type, max);
 	}
+      else if (POINTER_TYPE_P (type))
+	{
+	  wide_int max
+	    = wi::max_value (TYPE_PRECISION (type), TYPE_SIGN (type));
+	  return wide_int_to_tree (type, max);
+	}
       else
 	{
 	  gcc_assert (INTEGRAL_TYPE_P (type));
diff --git a/gcc/testsuite/gcc.dg/autopar/pr46193.c b/gcc/testsuite/gcc.dg/autopar/pr46193.c
new file mode 100644
index 0000000..544a5da
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/autopar/pr46193.c
@@ -0,0 +1,38 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -ftree-parallelize-loops=2 -fdump-tree-parloops-details" } */
+
+extern void abort (void);
+
+char *
+foo (int count, char **list)
+{
+  char *minaddr = list[0];
+  int i;
+
+  for (i = 0; i < count; i++)
+    {
+      char *addr = list[i];
+      if (addr < minaddr)
+	minaddr = addr;
+    }
+
+  return minaddr;
+}
+
+char *
+foo2 (int count, char **list)
+{
+  char *maxaddr = list[0];
+  int i;
+
+  for (i = 0; i < count; i++)
+    {
+      char *addr = list[i];
+      if (addr > maxaddr)
+	maxaddr = addr;
+    }
+
+  return maxaddr;
+}
+
+/* { dg-final { scan-tree-dump-times "parallelizing inner loop" 2 "parloops" } } */
diff --git a/libgomp/testsuite/libgomp.c/pr46193.c b/libgomp/testsuite/libgomp.c/pr46193.c
new file mode 100644
index 0000000..1e27faf
--- /dev/null
+++ b/libgomp/testsuite/libgomp.c/pr46193.c
@@ -0,0 +1,67 @@
+/* { dg-do run } */
+/* { dg-additional-options "-ftree-parallelize-loops=2" } */
+
+extern void abort (void);
+
+char *
+foo (int count, char **list)
+{
+  char *minaddr = list[0];
+  int i;
+
+  for (i = 0; i < count; i++)
+    {
+      char *addr = list[i];
+      if (addr < minaddr)
+	minaddr = addr;
+    }
+
+  return minaddr;
+}
+
+char *
+foo2 (int count, char **list)
+{
+  char *maxaddr = list[0];
+  int i;
+
+  for (i = 0; i < count; i++)
+    {
+      char *addr = list[i];
+      if (addr > maxaddr)
+	maxaddr = addr;
+    }
+
+  return maxaddr;
+}
+
+#define N 5
+
+static void
+init (char **list)
+{
+  int i;
+  for (i = 0; i < N; ++i)
+    list[i] = (char *)&list[i];
+}
+
+int
+main (void)
+{
+  char *list[N];
+  char * res;
+
+  init (list);
+
+  res = foo (N, list);
+
+  if (res != (char *)&list[0])
+    abort ();
+
+  res = foo2 (N, list);
+
+  if (res != (char *)&list[N-1])
+    abort ();
+
+  return 0;
+}
-- 
1.9.1