From: Richard Biener <rguenther@suse.de>
Date: Thu, 24 Aug 2023 08:00:20 +0000 (+0200)
Subject: tree-optimization/111128 - fix shift pattern recog
X-Git-Tag: basepoints/gcc-15~6702
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7b67cab154d4b5ec2a6bb62755da31cefbe63536;p=thirdparty%2Fgcc.git

tree-optimization/111128 - fix shift pattern recog

The following fixes placement of shift operand sanitization with
MIN when the original shift operand was external but the actual
one is not.

	PR tree-optimization/111128
	* tree-vect-patterns.cc (vect_recog_over_widening_pattern):
	Emit external shift operand inline if we promoted it with
	another pattern stmt.

	* gcc.dg/torture/pr111128.c: New testcase.
---

diff --git a/gcc/testsuite/gcc.dg/torture/pr111128.c b/gcc/testsuite/gcc.dg/torture/pr111128.c
new file mode 100644
index 000000000000..aa623b0d0452
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr111128.c
@@ -0,0 +1,16 @@
+/* { dg-do compile } */
+
+int a, b, c, e, g;
+short *d;
+unsigned char f;
+int h() {
+  f &= g;
+  for (; b; b++) {
+    a = 2;
+    for (; a; a--)
+      c = 0;
+    if (c)
+      continue;
+    e = (unsigned short)*d >> f;
+  }
+}
diff --git a/gcc/tree-vect-patterns.cc b/gcc/tree-vect-patterns.cc
index cda27fed95bb..a2ed0365b18c 100644
--- a/gcc/tree-vect-patterns.cc
+++ b/gcc/tree-vect-patterns.cc
@@ -3121,7 +3121,7 @@ vect_recog_over_widening_pattern (vec_info *vinfo,
 	    = gimple_build_assign (new_var, MIN_EXPR, ops[1],
 				   build_int_cst (op_type, new_precision - 1));
 	  gimple_set_location (pattern_stmt, gimple_location (last_stmt));
-	  if (unprom[1].dt == vect_external_def)
+	  if (ops[1] == unprom[1].op && unprom[1].dt == vect_external_def)
 	    {
 	      if (edge e = vect_get_external_def_edge (vinfo, ops[1]))
 		{