* builtins.c (get_memory_rtx): Always put into alias set 0.

	* gcc.c-torture/execute/20000703-1.c: New test.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@34849 138bc75d-0d04-0410-961f-82ee72b054a4

4 files changed, 50 insertions, 0 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 900ca82fede..9dbde733a0a 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,7 @@
+2000-07-03  Jakub Jelinek  <jakub@redhat.com>
+
+	* builtins.c (get_memory_rtx): Always put into alias set 0.
+
 2000-07-03  Nick Clifton  <nickc@cygnus.com>
 
 	* config/arm/arm.md: Fix post increment and pre increment
diff --git a/gcc/builtins.c b/gcc/builtins.c
index 0e89481a12b..56e6c265caf 100644
--- a/gcc/builtins.c
+++ b/gcc/builtins.c
@@ -558,6 +558,9 @@ get_memory_rtx (exp)
     return mem;
 
   set_mem_attributes (mem, exp, 0);
+
+  /* memcpy, memset and other builtin stringops can alias with anything. */
+  MEM_ALIAS_SET (mem) = 0;
   return mem;
 }
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 5de979c89a0..283c2b52f07 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2000-07-03  Jakub Jelinek  <jakub@redhat.com>
+
+	* gcc.c-torture/execute/20000703-1.c: New test.
+
 2000-07-03  Nathan Sidwell  <nathan@codesourcery.com>
 
 	* g++.old-deja/g++.pt (lookup10.C): New test.
diff --git a/gcc/testsuite/gcc.c-torture/execute/20000703-1.c b/gcc/testsuite/gcc.c-torture/execute/20000703-1.c
new file mode 100644
index 00000000000..55bdf74df22
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/20000703-1.c
@@ -0,0 +1,39 @@
+void abort(void);
+void exit(int);
+struct baz 
+{
+  char a[17];
+  char b[3];
+  unsigned int c;
+  unsigned int d;
+};
+
+void foo(struct baz *p, unsigned int c, unsigned int d)
+{
+  __builtin_memcpy (p->b, "abc", 3);
+  p->c = c;
+  p->d = d;
+}
+
+void bar(struct baz *p, unsigned int c, unsigned int d)
+{
+  ({ void *s = (p);
+     __builtin_memset (s, '\0', sizeof (struct baz));
+     s; });
+  __builtin_memcpy (p->a, "01234567890123456", 17);
+  __builtin_memcpy (p->b, "abc", 3);
+  p->c = c;
+  p->d = d;
+}
+
+int main()
+{
+  struct baz p;
+  foo(&p, 71, 18);
+  if (p.c != 71 || p.d != 18)
+    abort();
+  bar(&p, 59, 26);
+  if (p.c != 59 || p.d != 26)
+    abort();
+  exit(0);
+}