From: Richard Biener <rguenther@suse.de>
Date: Wed, 12 Jan 2022 07:10:19 +0000 (+0100)
Subject: tree-optimization/76174 - testcase for fixed PR
X-Git-Tag: basepoints/gcc-13~1800
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=45ddb395187f8f5f278880fe1422d8958ac35da6;p=thirdparty%2Fgcc.git

tree-optimization/76174 - testcase for fixed PR

This adds a testcase for the fixed PR, VN now gets us the transform
via IV equality plus predication.

2022-01-12  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/76174
	* gcc.dg/tree-ssa/pr76174.c: New testcase.
---

diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr76174.c b/gcc/testsuite/gcc.dg/tree-ssa/pr76174.c
new file mode 100644
index 000000000000..17a4a0faf242
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr76174.c
@@ -0,0 +1,22 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-cddce1" } */
+
+void foo();
+
+void l(unsigned int r) {
+  	unsigned int q = 0;
+        unsigned int c = r;
+        for (unsigned int x = 0; x<r; x++) {
+            if (q == c) {
+                foo();
+                c *= 2;
+            }
+            q++;
+        }
+}
+
+/* We should be able to elide the body of the function by means of
+   figuring out the equality between the two IVs and then simplifying
+   the q == c test.  */
+/* { dg-final { scan-tree-dump-not "foo" "cddce1" } } */
+/* { dg-final { scan-tree-dump-times "bb" 1 "cddce1" } } */