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authorMichael Shalayeff <mickey@cvs.openbsd.org>2004-01-28 01:39:41 +0000
committerMichael Shalayeff <mickey@cvs.openbsd.org>2004-01-28 01:39:41 +0000
commiteb2015b73fc7e8f74be0338c16e873a01653fe03 (patch)
treea0a1beaa9bc6601b949ea8937d79f939833b3cd3 /sys/arch/amd64/include/ieee.h
parentfc744b6d0908de21ef8f71c7e15dd3b113e9aad8 (diff)
an amd64 arch support.
hacked by art@ from netbsd sources and then later debugged by me into the shape where it can host itself. no bootloader yet as needs redoing from the recent advanced i386 sources (anyone? ;)
Diffstat (limited to 'sys/arch/amd64/include/ieee.h')
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1 files changed, 133 insertions, 0 deletions
diff --git a/sys/arch/amd64/include/ieee.h b/sys/arch/amd64/include/ieee.h
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+++ b/sys/arch/amd64/include/ieee.h
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+/* $OpenBSD: ieee.h,v 1.1 2004/01/28 01:39:39 mickey Exp $ */
+/* $NetBSD: ieee.h,v 1.1 1996/09/30 16:34:25 ws Exp $ */
+
+/*
+ * Copyright (c) 1992, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * This software was developed by the Computer Systems Engineering group
+ * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
+ * contributed to Berkeley.
+ *
+ * All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Lawrence Berkeley Laboratory.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * @(#)ieee.h 8.1 (Berkeley) 6/11/93
+ */
+
+/*
+ * ieee.h defines the machine-dependent layout of the machine's IEEE
+ * floating point. It does *not* define (yet?) any of the rounding
+ * mode bits, exceptions, and so forth.
+ */
+
+/*
+ * Define the number of bits in each fraction and exponent.
+ *
+ * k k+1
+ * Note that 1.0 x 2 == 0.1 x 2 and that denorms are represented
+ *
+ * (-exp_bias+1)
+ * as fractions that look like 0.fffff x 2 . This means that
+ *
+ * -126
+ * the number 0.10000 x 2 , for instance, is the same as the normalized
+ *
+ * -127 -128
+ * float 1.0 x 2 . Thus, to represent 2 , we need one leading zero
+ *
+ * -129
+ * in the fraction; to represent 2 , we need two, and so on. This
+ *
+ * (-exp_bias-fracbits+1)
+ * implies that the smallest denormalized number is 2
+ *
+ * for whichever format we are talking about: for single precision, for
+ *
+ * -126 -149
+ * instance, we get .00000000000000000000001 x 2 , or 1.0 x 2 , and
+ *
+ * -149 == -127 - 23 + 1.
+ */
+#define SNG_EXPBITS 8
+#define SNG_FRACBITS 23
+
+#define DBL_EXPBITS 11
+#define DBL_FRACBITS 52
+
+#define EXT_EXPBITS 15
+#define EXT_FRACBITS 112
+
+struct ieee_single {
+ u_int sng_frac:23;
+ u_int sng_exp:8;
+ u_int sng_sign:1;
+};
+
+struct ieee_double {
+ u_int dbl_fracl;
+ u_int dbl_frach:20;
+ u_int dbl_exp:11;
+ u_int dbl_sign:1;
+};
+
+struct ieee_ext {
+ u_int ext_fracl;
+ u_int ext_fraclm;
+ u_int ext_frachm;
+ u_int ext_frach:16;
+ u_int ext_exp:15;
+ u_int ext_sign:1;
+};
+
+/*
+ * Floats whose exponent is in [1..INFNAN) (of whatever type) are
+ * `normal'. Floats whose exponent is INFNAN are either Inf or NaN.
+ * Floats whose exponent is zero are either zero (iff all fraction
+ * bits are zero) or subnormal values.
+ *
+ * A NaN is a `signalling NaN' if its QUIETNAN bit is clear in its
+ * high fraction; if the bit is set, it is a `quiet NaN'.
+ */
+#define SNG_EXP_INFNAN 255
+#define DBL_EXP_INFNAN 2047
+#define EXT_EXP_INFNAN 32767
+
+#if 0
+#define SNG_QUIETNAN (1 << 22)
+#define DBL_QUIETNAN (1 << 19)
+#define EXT_QUIETNAN (1 << 15)
+#endif
+
+/*
+ * Exponent biases.
+ */
+#define SNG_EXP_BIAS 127
+#define DBL_EXP_BIAS 1023
+#define EXT_EXP_BIAS 16383