middle-end: don't lower past veclower [PR106063]

Hi All,

My previous patch can cause a problem if the pattern matches after veclower
as it may replace the construct with a vector sequence which the target may not
directly support.

As such don't perform the rewriting if after veclower unless the target supports
the operation.  If before veclower do the rewriting as well if the target didn't
support the original operation either.

gcc/ChangeLog:

	PR tree-optimization/106063
	* match.pd: Do not apply pattern after veclower is not supported.

gcc/testsuite/ChangeLog:

	PR tree-optimization/106063
	* gcc.dg/pr106063.c: New test.

(cherry picked from commit f7854e2faf7640230062dec3596e71773ca500ed)

diff --git a/gcc/match.pd b/gcc/match.pd
index fa59624d66b02db54d22616bae0f36c85a3b8cfe..e3bb7c9ae4cf412636bd39f5a6536ff2adb2ec6f 100644 (file)
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -5789,10 +5789,16 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
    (cmp (bit_and:c@2 @0 cst@1) integer_zerop)
     (with { tree csts = bitmask_inv_cst_vector_p (@1); }
      (if (csts && (VECTOR_TYPE_P (TREE_TYPE (@1)) || single_use (@2)))
-      (if (TYPE_UNSIGNED (TREE_TYPE (@1)))
-       (icmp @0 { csts; })
-       (with { tree utype = unsigned_type_for (TREE_TYPE (@1)); }
-        (icmp (view_convert:utype @0) { csts; }))))))))
+      (with { auto optab = VECTOR_TYPE_P (TREE_TYPE (@1))
+                        ? optab_vector : optab_default;
+             tree utype = unsigned_type_for (TREE_TYPE (@1)); }
+       (if (target_supports_op_p (utype, icmp, optab)
+           || (optimize_vectors_before_lowering_p ()
+               && (!target_supports_op_p (type, cmp, optab)
+                   || !target_supports_op_p (type, BIT_AND_EXPR, optab))))
+       (if (TYPE_UNSIGNED (TREE_TYPE (@1)))
+        (icmp @0 { csts; })
+        (icmp (view_convert:utype @0) { csts; })))))))))
 
 /* When one argument is a constant, overflow detection can be simplified.
    Currently restricted to single use so as not to interfere too much with

diff --git a/gcc/testsuite/gcc.dg/pr106063.c b/gcc/testsuite/gcc.dg/pr106063.c
new file mode 100644 (file)
index 0000000..b235967
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr106063.c
@@ -0,0 +1,9 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fno-tree-forwprop --disable-tree-evrp" } */
+typedef __int128 __attribute__((__vector_size__ (16))) V;
+
+V
+foo (V v)
+{
+  return (v & (V){15}) == v;
+}