builtins.c (expand_builtin_strcpy): Don't evaluate side-effects in src twice.

	* builtins.c (expand_builtin_strcpy): Don't evaluate side-effects in
	src twice.

	* gcc.c-torture/execute/string-opt-17.c: New test.

From-SVN: r68431

4 files changed, 55 insertions, 1 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 6b63396..518723f 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2003-06-24  Jakub Jelinek  <jakub@redhat.com>
+
+	* builtins.c (expand_builtin_strcpy): Don't evaluate side-effects in
+	src twice.
+
 2003-06-24  J"orn Rennecke <joern.rennecke@superh.com>
 
 	Back out these patches:
diff --git a/gcc/builtins.c b/gcc/builtins.c
index 97c3372..372c0c2 100644
--- a/gcc/builtins.c
+++ b/gcc/builtins.c
@@ -2788,7 +2788,7 @@ expand_builtin_strcpy (tree arglist, rtx target, enum machine_mode mode)
 
   src = TREE_VALUE (TREE_CHAIN (arglist));
   len = c_strlen (src);
-  if (len == 0)
+  if (len == 0 || TREE_SIDE_EFFECTS (len))
     return 0;
 
   dst = TREE_VALUE (arglist);
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 9a4ca69..2b8cff0 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2003-06-24  Jakub Jelinek  <jakub@redhat.com>
+
+	* gcc.c-torture/execute/string-opt-17.c: New test.
+
 2003-06-24  Mark Mitchell  <mark@codesourcery.com>
 
 	PR c++/5754
diff --git a/gcc/testsuite/gcc.c-torture/execute/string-opt-17.c b/gcc/testsuite/gcc.c-torture/execute/string-opt-17.c
new file mode 100644
index 0000000..76a351b
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/string-opt-17.c
@@ -0,0 +1,45 @@
+/* Copyright (C) 2003  Free Software Foundation.
+
+   Test strcpy optimizations don't evaluate side-effects twice.
+      
+   Written by Jakub Jelinek, June 23, 2003.  */
+
+typedef __SIZE_TYPE__ size_t;
+extern char *strcpy (char *, const char *);
+extern int memcmp (const void *, const void *, size_t);
+extern void abort (void);
+extern void exit (int);
+
+size_t
+test1 (char *s, size_t i)
+{
+  strcpy (s, "foobarbaz" + i++);
+  return i;
+}
+
+size_t
+check2 (void)
+{
+  static size_t r = 5;
+  if (r != 5)
+    abort ();
+  return ++r;
+}
+
+void
+test2 (char *s)
+{
+  strcpy (s, "foobarbaz" + check2 ());
+}
+
+int
+main (void)
+{
+  char buf[10];
+  if (test1 (buf, 7) != 8 || memcmp (buf, "az", 3))
+    abort ();
+  test2 (buf);
+  if (memcmp (buf, "baz", 4))
+    abort ();
+  exit (0);
+}