PR opt/3995

	* fold-const.c (sign_bit_p): New function.
	(fold) [EQ_EXPR]: Use this to convert (A & C) == 0 into A >= 0 and
        (A & C) != 0 into A < 0, when constant C is the sign bit of A's type.
	Reapply fold when converting (A & C) == C into (A & C) != 0.
	(fold_binary_op_with_conditional_arg): Fix typo in comment.

testsuite/
	* gcc.c-torture/execute/20020506-1.c: New test case.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@53241 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 333 insertions, 0 deletions

diff --git a/gcc/testsuite/gcc.c-torture/execute/20020506-1.c b/gcc/testsuite/gcc.c-torture/execute/20020506-1.c
new file mode 100644
index 00000000000..bcbd45bf6ca
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/20020506-1.c
@@ -0,0 +1,333 @@
+/* Copyright (C) 2002  Free Software Foundation.
+
+   Test that (A & C1) op C2 optimizations behave correctly where C1 is
+   a constant power of 2, op is == or !=, and C2 is C1 or zero.
+
+   Written by Roger Sayle, 5th May 2002.  */
+
+#include <limits.h>
+
+extern void abort (void);
+
+void test1 (signed char c, int set);
+void test2 (unsigned char c, int set);
+void test3 (short s, int set);
+void test4 (unsigned short s, int set);
+void test5 (int i, int set);
+void test6 (unsigned int i, int set);
+void test7 (long long l, int set);
+void test8 (unsigned long long l, int set);
+
+#ifndef LONG_LONG_MAX
+#define LONG_LONG_MAX __LONG_LONG_MAX__
+#endif
+#ifndef LONG_LONG_MIN
+#define LONG_LONG_MIN (-LONG_LONG_MAX-1)
+#endif
+#ifndef ULONG_LONG_MAX
+#define ULONG_LONG_MAX (LONG_LONG_MAX * 2ULL + 1)
+#endif
+
+
+void
+test1 (signed char c, int set)
+{
+  if ((c & (SCHAR_MAX+1)) == 0)
+    {
+      if (set) abort ();
+    }
+  else
+    if (!set) abort ();
+
+  if ((c & (SCHAR_MAX+1)) != 0)
+    {
+      if (!set) abort ();
+    }
+  else
+    if (set) abort ();
+
+  if ((c & (SCHAR_MAX+1)) == (SCHAR_MAX+1))
+    {
+      if (!set) abort ();
+    }
+  else
+    if (set) abort ();
+
+  if ((c & (SCHAR_MAX+1)) != (SCHAR_MAX+1))
+    {
+      if (set) abort ();
+    }
+  else
+    if (!set) abort ();
+}
+
+void
+test2 (unsigned char c, int set)
+{
+  if ((c & (SCHAR_MAX+1)) == 0)
+    {
+      if (set) abort ();
+    }
+  else
+    if (!set) abort ();
+
+  if ((c & (SCHAR_MAX+1)) != 0)
+    {
+      if (!set) abort ();
+    }
+  else
+    if (set) abort ();
+
+  if ((c & (SCHAR_MAX+1)) == (SCHAR_MAX+1))
+    {
+      if (!set) abort ();
+    }
+  else
+    if (set) abort ();
+
+  if ((c & (SCHAR_MAX+1)) != (SCHAR_MAX+1))
+    {
+      if (set) abort ();
+    }
+  else
+    if (!set) abort ();
+}
+
+void
+test3 (short s, int set)
+{
+  if ((s & (SHRT_MAX+1)) == 0)
+    {
+      if (set) abort ();
+    }
+  else
+    if (!set) abort ();
+
+  if ((s & (SHRT_MAX+1)) != 0)
+    {
+      if (!set) abort ();
+    }
+  else
+    if (set) abort ();
+
+  if ((s & (SHRT_MAX+1)) == (SHRT_MAX+1))
+    {
+      if (!set) abort ();
+    }
+  else
+    if (set) abort ();
+
+  if ((s & (SHRT_MAX+1)) != (SHRT_MAX+1))
+    {
+      if (set) abort ();
+    }
+  else
+    if (!set) abort ();
+}
+
+void
+test4 (unsigned short s, int set)
+{
+  if ((s & (SHRT_MAX+1)) == 0)
+    {
+      if (set) abort ();
+    }
+  else
+    if (!set) abort ();
+
+  if ((s & (SHRT_MAX+1)) != 0)
+    {
+      if (!set) abort ();
+    }
+  else
+    if (set) abort ();
+
+  if ((s & (SHRT_MAX+1)) == (SHRT_MAX+1))
+    {
+      if (!set) abort ();
+    }
+  else
+    if (set) abort ();
+
+  if ((s & (SHRT_MAX+1)) != (SHRT_MAX+1))
+    {
+      if (set) abort ();
+    }
+  else
+    if (!set) abort ();
+}
+
+void
+test5 (int i, int set)
+{
+  if ((i & (INT_MAX+1U)) == 0)
+    {
+      if (set) abort ();
+    }
+  else
+    if (!set) abort ();
+
+  if ((i & (INT_MAX+1U)) != 0)
+    {
+      if (!set) abort ();
+    }
+  else
+    if (set) abort ();
+
+  if ((i & (INT_MAX+1U)) == (INT_MAX+1U))
+    {
+      if (!set) abort ();
+    }
+  else
+    if (set) abort ();
+
+  if ((i & (INT_MAX+1U)) != (INT_MAX+1U))
+    {
+      if (set) abort ();
+    }
+  else
+    if (!set) abort ();
+}
+
+void
+test6 (unsigned int i, int set)
+{
+  if ((i & (INT_MAX+1U)) == 0)
+    {
+      if (set) abort ();
+    }
+  else
+    if (!set) abort ();
+
+  if ((i & (INT_MAX+1U)) != 0)
+    {
+      if (!set) abort ();
+    }
+  else
+    if (set) abort ();
+
+  if ((i & (INT_MAX+1U)) == (INT_MAX+1U))
+    {
+      if (!set) abort ();
+    }
+  else
+    if (set) abort ();
+
+  if ((i & (INT_MAX+1U)) != (INT_MAX+1U))
+    {
+      if (set) abort ();
+    }
+  else
+    if (!set) abort ();
+}
+
+void
+test7 (long long l, int set)
+{
+  if ((l & (LONG_LONG_MAX+1ULL)) == 0)
+    {
+      if (set) abort ();
+    }
+  else
+    if (!set) abort ();
+
+  if ((l & (LONG_LONG_MAX+1ULL)) != 0)
+    {
+      if (!set) abort ();
+    }
+  else
+    if (set) abort ();
+
+  if ((l & (LONG_LONG_MAX+1ULL)) == (LONG_LONG_MAX+1ULL))
+    {
+      if (!set) abort ();
+    }
+  else
+    if (set) abort ();
+
+  if ((l & (LONG_LONG_MAX+1ULL)) != (LONG_LONG_MAX+1ULL))
+    {
+      if (set) abort ();
+    }
+  else
+    if (!set) abort ();
+}
+
+void
+test8 (unsigned long long l, int set)
+{
+  if ((l & (LONG_LONG_MAX+1ULL)) == 0)
+    {
+      if (set) abort ();
+    }
+  else
+    if (!set) abort ();
+
+  if ((l & (LONG_LONG_MAX+1ULL)) != 0)
+    {
+      if (!set) abort ();
+    }
+  else
+    if (set) abort ();
+
+  if ((l & (LONG_LONG_MAX+1ULL)) == (LONG_LONG_MAX+1ULL))
+    {
+      if (!set) abort ();
+    }
+  else
+    if (set) abort ();
+
+  if ((l & (LONG_LONG_MAX+1ULL)) != (LONG_LONG_MAX+1ULL))
+    {
+      if (set) abort ();
+    }
+  else
+    if (!set) abort ();
+}
+
+int
+main ()
+{
+  test1 (0, 0);
+  test1 (SCHAR_MAX, 0);
+  test1 (SCHAR_MIN, 1);
+  test1 (UCHAR_MAX, 1);
+
+  test2 (0, 0);
+  test2 (SCHAR_MAX, 0);
+  test2 (SCHAR_MIN, 1);
+  test2 (UCHAR_MAX, 1);
+
+  test3 (0, 0);
+  test3 (SHRT_MAX, 0);
+  test3 (SHRT_MIN, 1);
+  test3 (USHRT_MAX, 1);
+
+  test4 (0, 0);
+  test4 (SHRT_MAX, 0);
+  test4 (SHRT_MIN, 1);
+  test4 (USHRT_MAX, 1);
+
+  test5 (0, 0);
+  test5 (INT_MAX, 0);
+  test5 (INT_MIN, 1);
+  test5 (UINT_MAX, 1);
+
+  test6 (0, 0);
+  test6 (INT_MAX, 0);
+  test6 (INT_MIN, 1);
+  test6 (UINT_MAX, 1);
+
+  test7 (0, 0);
+  test7 (LONG_LONG_MAX, 0);
+  test7 (LONG_LONG_MIN, 1);
+  test7 (ULONG_LONG_MAX, 1);
+
+  test8 (0, 0);
+  test8 (LONG_LONG_MAX, 0);
+  test8 (LONG_LONG_MIN, 1);
+  test8 (ULONG_LONG_MAX, 1);
+
+  return 0;
+}
+