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+/* FPU control word bits. Mips version.
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+ Copyright (C) 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
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+ This file is part of the GNU C Library.
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+ Contributed by Olaf Flebbe and Ralf Baechle.
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+
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+ The GNU C Library is free software; you can redistribute it and/or
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+ modify it under the terms of the GNU Lesser General Public
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+ License as published by the Free Software Foundation; either
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+ version 2.1 of the License, or (at your option) any later version.
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+
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+ The GNU C Library is distributed in the hope that it will be useful,
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+ but WITHOUT ANY WARRANTY; without even the implied warranty of
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+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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+ Lesser General Public License for more details.
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+
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+ You should have received a copy of the GNU Lesser General Public
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+ License along with the GNU C Library; if not, write to the Free
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+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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+ 02111-1307 USA. */
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+
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+#ifndef _FPU_CONTROL_H
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+#define _FPU_CONTROL_H
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+
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+/* MIPS FPU floating point control register bits.
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+ *
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+ * 31-25 -> floating point conditions code bits 7-1. These bits are only
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+ * available in MIPS IV.
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+ * 24 -> flush denormalized results to zero instead of
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+ * causing unimplemented operation exception. This bit is only
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+ * available for MIPS III and newer.
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+ * 23 -> Condition bit
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+ * 22-18 -> reserved (read as 0, write with 0)
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+ * 17 -> cause bit for unimplemented operation
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+ * 16 -> cause bit for invalid exception
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+ * 15 -> cause bit for division by zero exception
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+ * 14 -> cause bit for overflow exception
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+ * 13 -> cause bit for underflow exception
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+ * 12 -> cause bit for inexact exception
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+ * 11 -> enable exception for invalid exception
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+ * 10 -> enable exception for division by zero exception
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+ * 9 -> enable exception for overflow exception
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+ * 8 -> enable exception for underflow exception
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+ * 7 -> enable exception for inexact exception
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+ * 6 -> flag invalid exception
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+ * 5 -> flag division by zero exception
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+ * 4 -> flag overflow exception
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+ * 3 -> flag underflow exception
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+ * 2 -> flag inexact exception
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+ * 1-0 -> rounding control
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+ *
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+ *
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+ * Rounding Control:
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+ * 00 - rounding to nearest (RN)
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+ * 01 - rounding toward zero (RZ)
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+ * 10 - rounding (up) toward plus infinity (RP)
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+ * 11 - rounding (down)toward minus infinity (RM)
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+ */
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+
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+#include <features.h>
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+
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+/* masking of interrupts */
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+#define _FPU_MASK_V 0x0800 /* Invalid operation */
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+#define _FPU_MASK_Z 0x0400 /* Division by zero */
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+#define _FPU_MASK_O 0x0200 /* Overflow */
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+#define _FPU_MASK_U 0x0100 /* Underflow */
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+#define _FPU_MASK_I 0x0080 /* Inexact operation */
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+
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+/* flush denormalized numbers to zero */
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+#define _FPU_FLUSH_TZ 0x1000000
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+
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+/* rounding control */
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+#define _FPU_RC_NEAREST 0x0 /* RECOMMENDED */
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+#define _FPU_RC_ZERO 0x1
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+#define _FPU_RC_UP 0x2
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+#define _FPU_RC_DOWN 0x3
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+
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+#define _FPU_RESERVED 0xfe3c0000 /* Reserved bits in cw */
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+
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+
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+/* The fdlibm code requires strict IEEE double precision arithmetic,
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+ and no interrupts for exceptions, rounding to nearest. */
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+
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+#define _FPU_DEFAULT 0x00000000
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+
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+/* IEEE: same as above, but exceptions */
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+#define _FPU_IEEE 0x00000F80
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+
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+/* Type of the control word. */
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+typedef unsigned int fpu_control_t __attribute__ ((__mode__ (__SI__)));
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+
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+/* Macros for accessing the hardware control word. */
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+#define _FPU_GETCW(cw) __asm__ ("cfc1 %0,$31" : "=r" (cw))
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+#define _FPU_SETCW(cw) __asm__ ("ctc1 %0,$31" : : "r" (cw))
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+
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+/* Default control word set at startup. */
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+extern fpu_control_t __fpu_control;
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+
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+#endif /* fpu_control.h */
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