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-rw-r--r--ports/sysdeps/mips/fpu_control.h111
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diff --git a/ports/sysdeps/mips/fpu_control.h b/ports/sysdeps/mips/fpu_control.h
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+/* FPU control word bits.  Mips version.
+   Copyright (C) 1996, 1997, 1998, 1999, 2000, 2006, 2008
+   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, see
+   <http://www.gnu.org/licenses/>.  */
+
+#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>
+
+#ifdef __mips_soft_float
+
+#define _FPU_RESERVED 0xffffffff
+#define _FPU_DEFAULT  0x00000000
+typedef unsigned int fpu_control_t;
+#define _FPU_GETCW(cw) 0
+#define _FPU_SETCW(cw) do { } while (0)
+extern fpu_control_t __fpu_control;
+
+#else /* __mips_soft_float */
+
+/* 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__ volatile ("cfc1 %0,$31" : "=r" (cw))
+#define _FPU_SETCW(cw) __asm__ volatile ("ctc1 %0,$31" : : "r" (cw))
+
+/* Default control word set at startup.  */
+extern fpu_control_t __fpu_control;
+
+#endif /* __mips_soft_float */
+
+#endif	/* fpu_control.h */