openmp: Add OpenMP _BitInt support [PR113409]

The following patch adds support for _BitInt iterators of OpenMP canonical
loops (with the preexisting limitation that when not using compile time
static scheduling the iterators in the library are at most unsigned long long
or signed long, so one can't in the runtime/dynamic/guided etc. cases iterate
more than what those types can represent, like is the case of e.g. __int128
iterators too) and the testcase also covers linear/reduction clauses for them.

2024-01-17  Jakub Jelinek  <jakub@redhat.com>

	PR middle-end/113409
	* omp-general.cc (omp_adjust_for_condition): Handle BITINT_TYPE like
	INTEGER_TYPE.
	(omp_extract_for_data): Use build_bitint_type rather than
	build_nonstandard_integer_type if either iter_type or loop->v type
	is BITINT_TYPE.
	* omp-expand.cc (expand_omp_for_generic,
	expand_omp_taskloop_for_outer, expand_omp_taskloop_for_inner): Handle
	BITINT_TYPE like INTEGER_TYPE.

	* testsuite/libgomp.c/bitint-1.c: New test.

3 files changed, 84 insertions, 8 deletions

diff --git a/gcc/omp-expand.cc b/gcc/omp-expand.cc
index 6b9c917..2428782 100644
--- a/gcc/omp-expand.cc
+++ b/gcc/omp-expand.cc
@@ -4075,7 +4075,7 @@ expand_omp_for_generic (struct omp_region *region,
 
   /* See if we need to bias by LLONG_MIN.  */
   if (fd->iter_type == long_long_unsigned_type_node
-      && TREE_CODE (type) == INTEGER_TYPE
+      && (TREE_CODE (type) == INTEGER_TYPE || TREE_CODE (type) == BITINT_TYPE)
       && !TYPE_UNSIGNED (type)
       && fd->ordered == 0)
     {
@@ -7191,7 +7191,7 @@ expand_omp_taskloop_for_outer (struct omp_region *region,
 
   /* See if we need to bias by LLONG_MIN.  */
   if (fd->iter_type == long_long_unsigned_type_node
-      && TREE_CODE (type) == INTEGER_TYPE
+      && (TREE_CODE (type) == INTEGER_TYPE || TREE_CODE (type) == BITINT_TYPE)
       && !TYPE_UNSIGNED (type))
     {
       tree n1, n2;
@@ -7352,7 +7352,7 @@ expand_omp_taskloop_for_inner (struct omp_region *region,
 
   /* See if we need to bias by LLONG_MIN.  */
   if (fd->iter_type == long_long_unsigned_type_node
-      && TREE_CODE (type) == INTEGER_TYPE
+      && (TREE_CODE (type) == INTEGER_TYPE || TREE_CODE (type) == BITINT_TYPE)
       && !TYPE_UNSIGNED (type))
     {
       tree n1, n2;
diff --git a/gcc/omp-general.cc b/gcc/omp-general.cc
index bd4648f..2e31a3f 100644
--- a/gcc/omp-general.cc
+++ b/gcc/omp-general.cc
@@ -115,7 +115,8 @@ omp_adjust_for_condition (location_t loc, enum tree_code *cond_code, tree *n2,
 
     case NE_EXPR:
       gcc_assert (TREE_CODE (step) == INTEGER_CST);
-      if (TREE_CODE (TREE_TYPE (v)) == INTEGER_TYPE)
+      if (TREE_CODE (TREE_TYPE (v)) == INTEGER_TYPE
+	  || TREE_CODE (TREE_TYPE (v)) == BITINT_TYPE)
 	{
 	  if (integer_onep (step))
 	    *cond_code = LT_EXPR;
@@ -409,6 +410,7 @@ omp_extract_for_data (gomp_for *for_stmt, struct omp_for_data *fd,
       loop->v = gimple_omp_for_index (for_stmt, i);
       gcc_assert (SSA_VAR_P (loop->v));
       gcc_assert (TREE_CODE (TREE_TYPE (loop->v)) == INTEGER_TYPE
+		  || TREE_CODE (TREE_TYPE (loop->v)) == BITINT_TYPE
 		  || TREE_CODE (TREE_TYPE (loop->v)) == POINTER_TYPE);
       var = TREE_CODE (loop->v) == SSA_NAME ? SSA_NAME_VAR (loop->v) : loop->v;
       loop->n1 = gimple_omp_for_initial (for_stmt, i);
@@ -479,9 +481,17 @@ omp_extract_for_data (gomp_for *for_stmt, struct omp_for_data *fd,
 	  else if (i == 0
 		   || TYPE_PRECISION (iter_type)
 		      < TYPE_PRECISION (TREE_TYPE (loop->v)))
-	    iter_type
-	      = build_nonstandard_integer_type
-		  (TYPE_PRECISION (TREE_TYPE (loop->v)), 1);
+	    {
+	      if (TREE_CODE (iter_type) == BITINT_TYPE
+		  || TREE_CODE (TREE_TYPE (loop->v)) == BITINT_TYPE)
+		iter_type
+		  = build_bitint_type (TYPE_PRECISION (TREE_TYPE (loop->v)),
+				       1);
+	      else
+		iter_type
+		  = build_nonstandard_integer_type
+			(TYPE_PRECISION (TREE_TYPE (loop->v)), 1);
+	    }
 	}
       else if (iter_type != long_long_unsigned_type_node)
 	{
@@ -747,7 +757,8 @@ omp_extract_for_data (gomp_for *for_stmt, struct omp_for_data *fd,
 	  if (t && integer_zerop (t))
 	    count = build_zero_cst (long_long_unsigned_type_node);
 	  else if ((i == 0 || count != NULL_TREE)
-		   && TREE_CODE (TREE_TYPE (loop->v)) == INTEGER_TYPE
+		   && (TREE_CODE (TREE_TYPE (loop->v)) == INTEGER_TYPE
+		       || TREE_CODE (TREE_TYPE (loop->v)) == BITINT_TYPE)
 		   && TREE_CONSTANT (loop->n1)
 		   && TREE_CONSTANT (loop->n2)
 		   && TREE_CODE (loop->step) == INTEGER_CST)
diff --git a/libgomp/testsuite/libgomp.c/bitint-1.c b/libgomp/testsuite/libgomp.c/bitint-1.c
new file mode 100644
index 0000000..4b55a19
--- /dev/null
+++ b/libgomp/testsuite/libgomp.c/bitint-1.c
@@ -0,0 +1,65 @@
+/* PR middle-end/113409 */
+/* { dg-do run { target bitint } } */
+
+extern void abort (void);
+
+#if __BITINT_MAXWIDTH__ >= 1023
+typedef _BitInt(931) B931;
+typedef _BitInt(1023) B1023;
+#else
+typedef _BitInt(31) B931;
+typedef _BitInt(63) B1023;
+#endif
+
+__attribute__((noipa)) B931
+bar (B931 x)
+{
+  return x;
+}
+
+B931
+foo (B931 x)
+{
+  B931 r = 0;
+  B1023 l = 56wb;
+  #pragma omp parallel for reduction(+: r) linear(l : 3wb)
+  for (B931 i = 0; i < x; ++i)
+    {
+      r += bar (i);
+      l += 3wb;
+    }
+  if (l != (B1023) 56wb + x * 3wb)
+    abort ();
+  return r;
+}
+
+B931
+baz (B931 a, B931 b, B931 c, B931 d, B931 e, B931 f)
+{
+  B931 r = 0;
+  #pragma omp parallel for collapse (2wb) reduction(+: r)
+  for (B931 i = a; i < b; i += c)
+    for (B931 j = d; j > e; j += f)
+{
+      r += (j - d) / f;
+__builtin_printf ("%d\n", (int) r);
+}
+  return r;
+}
+
+int
+main ()
+{
+  if (foo (16wb) != (B931) 15wb * 16wb / 2
+      || foo (256wb) != (B931) 255wb * 256wb / 2)
+    abort ();
+#if __BITINT_MAXWIDTH__ >= 1023
+  if (baz (5019676379303764570412381742937286053482001129028025397398691108125646744814606405323608429353439158482254231750681261083217232780938592007150824765654203477280876662295642053702075485153212701225737143207062700602509893062044376997132415613866154761073993220684129908568716699977wb,
+           5019676379303764570412381742937286053482001129028025397398691108125646744814606405323608429353439158482254231750681261083217232780938592007150824765654203477280876662295642053702075485153212701225737143207062700602509893062044376997132415613866154761074023903103954348393149593648wb,
+           398472984732984732894723wb,
+           5145599438319070078334010989312672300490893251953772234670751860213136881221517063143096309285807356778798661066289865489661268190588670564647904159660341525674865064477335008915374460378741763629714814990575971883514175167056160470289039998140910732382754821232566561860399556131wb,
+           5145599438319070078334010989312672300490893251953772234670751860213136881221517063143096309285807356778798661066289865489661268190588670564647904159660341525674865064477335008915374460378741763629714814990575971883514175167056160470289039995725068563774878643356388697468035164019wb,
+           -89475635874365784365784365347865347856wb) != (B931) 26wb * 27wb / 2wb * 77wb)
+    abort ();
+#endif
+}