bitint: Handle complex types in build_bitint_stmt_ssa_conflicts [PR114425]

The task of the build_bitint_stmt_ssa_conflicts hook for
tree-ssa-coalesce.cc next to special casing the
multiplication/division/modulo is to ignore statements with
large/huge _BitInt lhs which isn't in names bitmap and on the
other side pretend all uses of the stmt are used in a later stmt
(single user of that SSA_NAME or perhaps single user of lhs of
the single user etc.) where the lowering will actually emit the
code.

Unfortunately the function wasn't handling COMPLEX_TYPE of the large/huge
BITINT_TYPE, while the FE doesn't really support such types, they are
used under the hood for __builtin_{add,sub,mul}_overflow{,_p}, they are
also present or absent from the names bitmap and should be treated the same.

Without this patch, the operands of .ADD_OVERFLOW were incorrectly pretended
to be used right in that call statement rather than on the cast stmt from
IMAGPART_EXPR of .ADD_OVERFLOW return value to some integral type.

2024-03-23  Jakub Jelinek  <jakub@redhat.com>

	PR tree-optimization/114425
	* gimple-lower-bitint.cc (build_bitint_stmt_ssa_conflicts): Handle
	_Complex large/huge _BitInt types like the large/huge _BitInt types.

	* gcc.dg/torture/bitint-67.c: New test.

diff --git a/gcc/gimple-lower-bitint.cc b/gcc/gimple-lower-bitint.cc
index 8c268005dfd02c93a1f22b8149fc63e355548ec9..6f13c657c6b825f8e0532cb3a8016802759244c2 100644 (file)
--- a/gcc/gimple-lower-bitint.cc
+++ b/gcc/gimple-lower-bitint.cc
@@ -5902,20 +5902,25 @@ build_bitint_stmt_ssa_conflicts (gimple *stmt, live_track *live,
   if (is_gimple_assign (stmt))
     {
       lhs = gimple_assign_lhs (stmt);
-      if (TREE_CODE (lhs) == SSA_NAME
-         && TREE_CODE (TREE_TYPE (lhs)) == BITINT_TYPE
-         && bitint_precision_kind (TREE_TYPE (lhs)) >= bitint_prec_large)
+      if (TREE_CODE (lhs) == SSA_NAME)
        {
-         if (!bitmap_bit_p (names, SSA_NAME_VERSION (lhs)))
-           return;
-         switch (gimple_assign_rhs_code (stmt))
+         tree type = TREE_TYPE (lhs);
+         if (TREE_CODE (type) == COMPLEX_TYPE)
+           type = TREE_TYPE (type);
+         if (TREE_CODE (type) == BITINT_TYPE
+             && bitint_precision_kind (type) >= bitint_prec_large)
            {
-           case MULT_EXPR:
-           case TRUNC_DIV_EXPR:
-           case TRUNC_MOD_EXPR:
-             muldiv_p = true;
-           default:
-             break;
+             if (!bitmap_bit_p (names, SSA_NAME_VERSION (lhs)))
+               return;
+             switch (gimple_assign_rhs_code (stmt))
+               {
+               case MULT_EXPR:
+               case TRUNC_DIV_EXPR:
+               case TRUNC_MOD_EXPR:
+                 muldiv_p = true;
+               default:
+                 break;
+               }
            }
        }
     }
@@ -5947,27 +5952,37 @@ build_bitint_stmt_ssa_conflicts (gimple *stmt, live_track *live,
 
   auto_vec<tree, 16> worklist;
   FOR_EACH_SSA_TREE_OPERAND (var, stmt, iter, SSA_OP_USE)
-    if (TREE_CODE (TREE_TYPE (var)) == BITINT_TYPE
-       && bitint_precision_kind (TREE_TYPE (var)) >= bitint_prec_large)
-      {
-       if (bitmap_bit_p (names, SSA_NAME_VERSION (var)))
-         use (live, var);
-       else
-         worklist.safe_push (var);
-      }
+    {
+      tree type = TREE_TYPE (var);
+      if (TREE_CODE (type) == COMPLEX_TYPE)
+       type = TREE_TYPE (type);
+      if (TREE_CODE (type) == BITINT_TYPE
+         && bitint_precision_kind (type) >= bitint_prec_large)
+       {
+         if (bitmap_bit_p (names, SSA_NAME_VERSION (var)))
+           use (live, var);
+         else
+           worklist.safe_push (var);
+       }
+    }
 
   while (worklist.length () > 0)
     {
       tree s = worklist.pop ();
       FOR_EACH_SSA_TREE_OPERAND (var, SSA_NAME_DEF_STMT (s), iter, SSA_OP_USE)
-       if (TREE_CODE (TREE_TYPE (var)) == BITINT_TYPE
-           && bitint_precision_kind (TREE_TYPE (var)) >= bitint_prec_large)
-         {
-           if (bitmap_bit_p (names, SSA_NAME_VERSION (var)))
-             use (live, var);
-           else
-             worklist.safe_push (var);
-         }
+       {
+         tree type = TREE_TYPE (var);
+         if (TREE_CODE (type) == COMPLEX_TYPE)
+           type = TREE_TYPE (type);
+         if (TREE_CODE (type) == BITINT_TYPE
+             && bitint_precision_kind (type) >= bitint_prec_large)
+           {
+             if (bitmap_bit_p (names, SSA_NAME_VERSION (var)))
+               use (live, var);
+             else
+               worklist.safe_push (var);
+           }
+       }
     }
 
   if (muldiv_p)

diff --git a/gcc/testsuite/gcc.dg/torture/bitint-67.c b/gcc/testsuite/gcc.dg/torture/bitint-67.c
new file mode 100644 (file)
index 0000000..b5621e1
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/bitint-67.c
@@ -0,0 +1,29 @@
+/* PR tree-optimization/114425 */
+/* { dg-do run { target bitint } } */
+/* { dg-options "-std=c23" } */
+/* { dg-skip-if "" { ! run_expensive_tests }  { "*" } { "-O0" "-O2" } } */
+/* { dg-skip-if "" { ! run_expensive_tests } { "-flto" } { "" } } */
+
+#if __BITINT_MAXWIDTH__ >= 2000
+_BitInt(8) a;
+_BitInt(300) b;
+_BitInt(2000) c;
+
+__attribute__((noipa)) unsigned
+foo (_BitInt(2000) d)
+{
+  int o = __builtin_add_overflow_p (d, 0, b);
+  _BitInt(2000) m = c * a;
+  unsigned u = m;
+  return u + o;
+}
+#endif
+
+int
+main ()
+{
+#if __BITINT_MAXWIDTH__ >= 2000
+  if (foo (0xfa7ac16f2613255eeb217e871c1f02221e26ce11f82d6a33206ec0ad5d4414722019933c0e2wb) != 1)
+    __builtin_abort ();
+#endif
+}