Chris Zankel writes:

The following patches add support for the Xtensa processor architecture
to uClibc. They are based on a recent SVN checkout (12/05/2007).

The first patch (attached to this post) adds Xtensa support to various
shared configuration and make files. The following patches then include
the Xtensa specific files and directories.

I welcome any feedback and would appreciate it if you could include the
patches into the mainline tree. I am certainly committed to maintain the port. 

Bob Wilson was kind enough to review the patches.

Some notes about the architecture: Xtensa is a configurable and
extensible processor architecture developed by Tensilica. For more
information, please visit: www.linux-xtensa.org.

1 files changed, 43 insertions, 0 deletions

diff --git a/libc/sysdeps/linux/xtensa/bits/mathdef.h b/libc/sysdeps/linux/xtensa/bits/mathdef.h
new file mode 100644
index 000000000..0177fa9fc
--- /dev/null
+++ b/libc/sysdeps/linux/xtensa/bits/mathdef.h
@@ -0,0 +1,43 @@
+/* Copyright (C) 2000, 2001, 2004, 2007
+   Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
+   Boston, MA 02110-1301, USA.  */
+
+#if !defined _MATH_H && !defined _COMPLEX_H
+# error "Never use <bits/mathdef.h> directly; include <math.h> instead"
+#endif
+
+#if defined __USE_ISOC99 && defined _MATH_H && !defined _MATH_H_MATHDEF
+# define _MATH_H_MATHDEF	1
+
+/* Xtensa has `float' and `double' operations.  */
+typedef float float_t;		/* `float' expressions are evaluated as
+				   `float'.  */
+typedef double double_t;	/* `double' expressions are evaluated as
+				   `double'.  */
+
+/* The values returned by `ilogb' for 0 and NaN respectively.  */
+# define FP_ILOGB0	(-2147483647)
+# define FP_ILOGBNAN	2147483647
+
+#endif	/* ISO C99 */
+
+#ifndef __NO_LONG_DOUBLE_MATH
+/* Signal that we do not really have a `long double'.  The disables the
+   declaration of all the `long double' function variants.  */
+# define __NO_LONG_DOUBLE_MATH	1
+#endif