On 12/22/2017 05:44 PM, Jakub Jelinek wrote:
> You need to do that only if (!is_gimple_val (arg1_len)).
> Can you please emit the additional stmt only if that isn't true?
Sure.
This is what I'm going to install.
Martin
>From 509e884e909a0b2ed56bf025c852f30b9ed43ae1 Mon Sep 17 00:00:00 2001
From: marxin <mli...@suse.cz>
Date: Fri, 22 Dec 2017 12:37:17 +0100
Subject: [PATCH] Assign result of get_string_lenth to a SSA_NAME (PR
tree-optimization/83552).
gcc/ChangeLog:
2017-12-22 Martin Liska <mli...@suse.cz>
PR tree-optimization/83552
* tree-ssa-strlen.c (fold_strstr_to_strncmp): Assign result
of get_string_lenth to a SSA_NAME if not a GIMPLE value.
gcc/testsuite/ChangeLog:
2017-12-22 Martin Liska <mli...@suse.cz>
PR tree-optimization/83552
* gcc.dg/pr83552.c: New test.
---
gcc/testsuite/gcc.dg/pr83552.c | 13 +++++++++++++
gcc/tree-ssa-strlen.c | 10 ++++++++++
2 files changed, 23 insertions(+)
create mode 100644 gcc/testsuite/gcc.dg/pr83552.c
diff --git a/gcc/testsuite/gcc.dg/pr83552.c b/gcc/testsuite/gcc.dg/pr83552.c
new file mode 100644
index 00000000000..993cdd26581
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr83552.c
@@ -0,0 +1,13 @@
+/* PR tree-optimization/83364 */
+/* { dg-options "-O2" } */
+
+char *b;
+char d[100];
+void a ();
+void
+c (void)
+{
+ __builtin_strcat (d, "12345");
+ if (__builtin_strstr (b, d) == b)
+ a ();
+}
diff --git a/gcc/tree-ssa-strlen.c b/gcc/tree-ssa-strlen.c
index e812bd1e735..be6ab9f1e1b 100644
--- a/gcc/tree-ssa-strlen.c
+++ b/gcc/tree-ssa-strlen.c
@@ -3005,6 +3005,16 @@ fold_strstr_to_strncmp (tree rhs1, tree rhs2, gimple *stmt)
{
gimple_stmt_iterator gsi = gsi_for_stmt (call_stmt);
tree strncmp_decl = builtin_decl_explicit (BUILT_IN_STRNCMP);
+
+ if (!is_gimple_val (arg1_len))
+ {
+ tree arg1_len_tmp = make_ssa_name (TREE_TYPE (arg1_len));
+ gassign *arg1_stmt = gimple_build_assign (arg1_len_tmp,
+ arg1_len);
+ gsi_insert_before (&gsi, arg1_stmt, GSI_SAME_STMT);
+ arg1_len = arg1_len_tmp;
+ }
+
gcall *strncmp_call = gimple_build_call (strncmp_decl, 3,
arg0, arg1, arg1_len);
tree strncmp_lhs = make_ssa_name (integer_type_node);
--
2.14.3
