lower-bitint: Fix a typo in a condition [PR113323]

The following testcase revealed a typo in condition, as the comment
says the intent is
       /*  If lhs of stmt is large/huge _BitInt SSA_NAME not in m_names
           it means it will be handled in a loop or straight line code
           at the location of its (ultimate) immediate use, so for
           vop checking purposes check these only at the ultimate
           immediate use.  */
but the condition was using != BITINT_TYPE rather than == BITINT_TYPE,
so e.g. it used bitint_precision_kind on non-BITINT_TYPEs (e.g. on vector
types it will crash because TYPE_PRECISION means something different there,
or on say INTEGER_TYPEs the precision will never be large enough to be >=
bitint_prec_large).

The following patch fixes that.

2024-01-12  Jakub Jelinek  <jakub@redhat.com>

	PR tree-optimization/113323
	* gimple-lower-bitint.cc (bitint_dom_walker::before_dom_children): Fix
	check for lhs being large/huge _BitInt not in m_names.

	* gcc.dg/bitint-68.c: New test.

diff --git a/gcc/gimple-lower-bitint.cc b/gcc/gimple-lower-bitint.cc
index ea616ea41534f2d2a780a9e82fde2150c54996f2..f1e4cd01cb06e93b6bb270c6ee7b1661da033f66 100644 (file)
--- a/gcc/gimple-lower-bitint.cc
+++ b/gcc/gimple-lower-bitint.cc
@@ -5513,7 +5513,7 @@ bitint_dom_walker::before_dom_children (basic_block bb)
       tree lhs = gimple_get_lhs (stmt);
       if (lhs
          && TREE_CODE (lhs) == SSA_NAME
-         && TREE_CODE (TREE_TYPE (lhs)) != BITINT_TYPE
+         && TREE_CODE (TREE_TYPE (lhs)) == BITINT_TYPE
          && bitint_precision_kind (TREE_TYPE (lhs)) >= bitint_prec_large
          && !bitmap_bit_p (m_names, SSA_NAME_VERSION (lhs)))
        /* If lhs of stmt is large/huge _BitInt SSA_NAME not in m_names,

diff --git a/gcc/testsuite/gcc.dg/bitint-68.c b/gcc/testsuite/gcc.dg/bitint-68.c
new file mode 100644 (file)
index 0000000..092f31a
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/bitint-68.c
@@ -0,0 +1,14 @@
+/* PR tree-optimization/113323 */
+/* { dg-do compile { target bitint575 } } */
+/* { dg-options "-std=c23 -O2" } */
+
+typedef long __attribute__((__vector_size__ (16))) V;
+V u, v;
+_BitInt(535) i;
+
+void
+foo (void)
+{
+  while (i)
+    u = v;
+}