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authorEric Andersen <andersen@codepoet.org>2003-10-08 19:30:43 +0000
committerEric Andersen <andersen@codepoet.org>2003-10-08 19:30:43 +0000
commit027d12aeef4386c638f73a4df7171a5d027604f4 (patch)
tree707c31a6ee5b51ed82369389f849aea2c72ec716 /libc/sysdeps/linux/mips/fpu_control.h
parent1bdf3c0a8f4ad63e78559a6963ed62a8c2fc516c (diff)
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.
Diffstat (limited to 'libc/sysdeps/linux/mips/fpu_control.h')
-rw-r--r--libc/sysdeps/linux/mips/fpu_control.h98
1 files changed, 98 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/mips/fpu_control.h b/libc/sysdeps/linux/mips/fpu_control.h
new file mode 100644
index 000000000..da18deab5
--- /dev/null
+++ b/libc/sysdeps/linux/mips/fpu_control.h
@@ -0,0 +1,98 @@
+/* FPU control word bits. Mips version.
+ Copyright (C) 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Olaf Flebbe and Ralf Baechle.
+
+ 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
+
+/* MIPS FPU floating point control register bits.
+ *
+ * 31-25 -> floating point conditions code bits 7-1. These bits are only
+ * available in MIPS IV.
+ * 24 -> flush denormalized results to zero instead of
+ * causing unimplemented operation exception. This bit is only
+ * available for MIPS III and newer.
+ * 23 -> Condition bit
+ * 22-18 -> reserved (read as 0, write with 0)
+ * 17 -> cause bit for unimplemented operation
+ * 16 -> cause bit for invalid exception
+ * 15 -> cause bit for division by zero exception
+ * 14 -> cause bit for overflow exception
+ * 13 -> cause bit for underflow exception
+ * 12 -> cause bit for inexact exception
+ * 11 -> enable exception for invalid exception
+ * 10 -> enable exception for division by zero exception
+ * 9 -> enable exception for overflow exception
+ * 8 -> enable exception for underflow exception
+ * 7 -> enable exception for inexact exception
+ * 6 -> flag invalid exception
+ * 5 -> flag division by zero exception
+ * 4 -> flag overflow exception
+ * 3 -> flag underflow exception
+ * 2 -> flag inexact exception
+ * 1-0 -> rounding control
+ *
+ *
+ * Rounding Control:
+ * 00 - rounding to nearest (RN)
+ * 01 - rounding toward zero (RZ)
+ * 10 - rounding (up) toward plus infinity (RP)
+ * 11 - rounding (down)toward minus infinity (RM)
+ */
+
+#include <features.h>
+
+/* masking of interrupts */
+#define _FPU_MASK_V 0x0800 /* Invalid operation */
+#define _FPU_MASK_Z 0x0400 /* Division by zero */
+#define _FPU_MASK_O 0x0200 /* Overflow */
+#define _FPU_MASK_U 0x0100 /* Underflow */
+#define _FPU_MASK_I 0x0080 /* Inexact operation */
+
+/* flush denormalized numbers to zero */
+#define _FPU_FLUSH_TZ 0x1000000
+
+/* rounding control */
+#define _FPU_RC_NEAREST 0x0 /* RECOMMENDED */
+#define _FPU_RC_ZERO 0x1
+#define _FPU_RC_UP 0x2
+#define _FPU_RC_DOWN 0x3
+
+#define _FPU_RESERVED 0xfe3c0000 /* Reserved bits in cw */
+
+
+/* The fdlibm code requires strict IEEE double precision arithmetic,
+ and no interrupts for exceptions, rounding to nearest. */
+
+#define _FPU_DEFAULT 0x00000000
+
+/* IEEE: same as above, but exceptions */
+#define _FPU_IEEE 0x00000F80
+
+/* Type of the control word. */
+typedef unsigned int fpu_control_t __attribute__ ((__mode__ (__SI__)));
+
+/* Macros for accessing the hardware control word. */
+#define _FPU_GETCW(cw) __asm__ ("cfc1 %0,$31" : "=r" (cw))
+#define _FPU_SETCW(cw) __asm__ ("ctc1 %0,$31" : : "r" (cw))
+
+/* Default control word set at startup. */
+extern fpu_control_t __fpu_control;
+
+#endif /* fpu_control.h */