Patch from Atsushi Nemoto (with some additions):

Current uClibc contains only one fpu_control.h and it is i386 version.
This is a patch to use platform specific fpu_control.h.  All new files
come from glibc 2.3.2.  This patch is against 0.9.21 but also can be
applied to CVS as is.

1 files changed, 102 insertions, 0 deletions

diff --git a/libc/sysdeps/linux/arm/fpu_control.h b/libc/sysdeps/linux/arm/fpu_control.h
new file mode 100644
index 000000000..65912e496
--- /dev/null
+++ b/libc/sysdeps/linux/arm/fpu_control.h
@@ -0,0 +1,102 @@
+/* FPU control word definitions.  ARM version.
+   Copyright (C) 1996, 1997, 1998, 2000 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., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#ifndef _FPU_CONTROL_H
+#define _FPU_CONTROL_H
+
+/* We have a slight terminology confusion here.  On the ARM, the register
+ * we're interested in is actually the FPU status word - the FPU control
+ * word is something different (which is implementation-defined and only
+ * accessible from supervisor mode.)
+ *
+ * The FPSR looks like this:
+ *
+ *     31-24        23-16          15-8              7-0
+ * | system ID | trap enable | system control | exception flags |
+ *
+ * We ignore the system ID bits; for interest's sake they are:
+ *
+ *  0000	"old" FPE
+ *  1000	FPPC hardware
+ *  0001	FPE 400
+ *  1001	FPA hardware
+ *
+ * The trap enable and exception flags are both structured like this:
+ *
+ *     7 - 5     4     3     2     1     0
+ * | reserved | INX | UFL | OFL | DVZ | IVO |
+ *
+ * where a `1' bit in the enable byte means that the trap can occur, and
+ * a `1' bit in the flags byte means the exception has occurred.
+ *
+ * The exceptions are:
+ *
+ *  IVO - invalid operation
+ *  DVZ - divide by zero
+ *  OFL - overflow
+ *  UFL - underflow
+ *  INX - inexact (do not use; implementations differ)
+ *
+ * The system control byte looks like this:
+ *
+ *     7-5      4    3    2    1    0
+ * | reserved | AC | EP | SO | NE | ND |
+ *
+ * where the bits mean
+ *
+ *  ND - no denormalised numbers (force them all to zero)
+ *  NE - enable NaN exceptions
+ *  SO - synchronous operation
+ *  EP - use expanded packed-decimal format
+ *  AC - use alternate definition for C flag on compare operations
+ */
+
+/* masking of interrupts */
+#define _FPU_MASK_IM	0x00010000	/* invalid operation */
+#define _FPU_MASK_ZM	0x00020000	/* divide by zero */
+#define _FPU_MASK_OM	0x00040000	/* overflow */
+#define _FPU_MASK_UM	0x00080000	/* underflow */
+#define _FPU_MASK_PM	0x00100000	/* inexact */
+#define _FPU_MASK_DM	0x00000000	/* denormalized operation */
+
+/* The system id bytes cannot be changed.
+   Only the bottom 5 bits in the trap enable byte can be changed.
+   Only the bottom 5 bits in the system control byte can be changed.
+   Only the bottom 5 bits in the exception flags are used.
+   The exception flags are set by the fpu, but can be zeroed by the user. */
+#define _FPU_RESERVED	0xffe0e0e0	/* These bits are reserved.  */
+
+/* The fdlibm code requires strict IEEE double precision arithmetic,
+   no interrupts for exceptions, rounding to nearest.  Changing the
+   rounding mode will break long double I/O.  Turn on the AC bit,
+   the compiler generates code that assumes it is on.  */
+#define _FPU_DEFAULT	0x00001000	/* Default value.  */
+#define _FPU_IEEE	0x001f1000	/* Default + exceptions enabled. */
+
+/* Type of the control word.  */
+typedef unsigned int fpu_control_t;
+
+/* Macros for accessing the hardware control word.  */
+#define _FPU_GETCW(cw) __asm__ ("rfs %0" : "=r" (cw))
+#define _FPU_SETCW(cw) __asm__ ("wfs %0" : : "r" (cw))
+
+/* Default control word set at startup.  */
+extern fpu_control_t __fpu_control;
+
+#endif /* _FPU_CONTROL_H */