[PATCH] tree-optimization/110669 - bogus matching of loop bitop

[PATCH] tree-optimization/110669 - bogus matching of loop bitop

[Richard Biener]

The matching code lacked a check that we end up with a PHI node
in the loop header.  This caused us to match a random PHI argument
now catched by the extra PHI_ARG_DEF_FROM_EDGE checking.

Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed.

	PR tree-optimization/110669
	* tree-scalar-evolution.cc (analyze_and_compute_bitop_with_inv_effect):
	Check we matched a header PHI.

	* gcc.dg/torture/pr110669.c: New testcase.
---
 gcc/testsuite/gcc.dg/torture/pr110669.c | 15 +++++++++++++++
 gcc/tree-scalar-evolution.cc            |  1 +
 2 files changed, 16 insertions(+)
 create mode 100644 gcc/testsuite/gcc.dg/torture/pr110669.c

diff --git a/gcc/testsuite/gcc.dg/torture/pr110669.c b/gcc/testsuite/gcc.dg/torture/pr110669.c
new file mode 100644
index 00000000000..b0a9ea448f4
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr110669.c
@@ -0,0 +1,15 @@
+/* { dg-do compile } */
+
+int g_29, func_47_p_48, func_47_p_51_l_129;
+void func_47_p_51()
+{
+  for (;;)
+    {
+      func_47_p_51_l_129 = 0;
+      for (; func_47_p_51_l_129 <= 1; func_47_p_51_l_129 += 1)
+	{
+	  short *l_160 = (short *)(__UINTPTR_TYPE__)(func_47_p_48 || *l_160);
+	  *l_160 &= g_29;
+	}
+    }
+}
diff --git a/gcc/tree-scalar-evolution.cc b/gcc/tree-scalar-evolution.cc
index ba47a684f4b..2abe8fa0b90 100644
--- a/gcc/tree-scalar-evolution.cc
+++ b/gcc/tree-scalar-evolution.cc
@@ -3674,6 +3674,7 @@ analyze_and_compute_bitop_with_inv_effect (class loop* loop, tree phidef,
   if (TREE_CODE (match_op[1]) != SSA_NAME
       || !expr_invariant_in_loop_p (loop, match_op[0])
       || !(header_phi = dyn_cast <gphi *> (SSA_NAME_DEF_STMT (match_op[1])))
+      || gimple_bb (header_phi) != loop->header
       || gimple_phi_num_args (header_phi) != 2)
     return NULL_TREE;
 
-- 
2.35.3