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+/* Copyright (C) 1991, 1992, 1997, 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 _68881_SWITCH_H
+
+#define _68881_SWITCH_H 1
+#include <sys/cdefs.h>
+
+/* This is the format of the data at the code label for a function which
+ wants to switch depending on whether or not a 68881 is present.
+
+ Initially, `insn' is a `jsr' instruction, and `target' is __68881_switch.
+ The first time such a function is called, __68881_switch determines whether
+ or not a 68881 is present, and modifies the function accordingly.
+ Then `insn' is a `jmp' instruction, and `target' is the value of `fpu'
+ if there is 68881, or the value of `soft' if not. */
+
+struct switch_caller
+ {
+ unsigned short int insn; /* The `jsr' or `jmp' instruction. */
+ void *target; /* The target of the instruction. */
+ void *soft; /* The address of the soft function. */
+ void *fpu; /* The address of the 68881 function. */
+ };
+
+/* These are opcodes (values for `insn', above) for `jmp' and `jsr'
+ instructions, respectively, to 32-bit absolute addresses. */
+#define JMP 0x4ef9
+#define JSR 0x4eb9
+
+
+/* Function to determine whether or not a 68881 is available,
+ and modify its caller (which must be a `struct switch_caller', above,
+ in data space) to use the appropriate version. */
+extern void __68881_switch (int __dummy) __THROW;
+
+
+/* Define FUNCTION as a `struct switch_caller' which will call
+ `__FUNCTION_68881' if a 68881 is present, and `__FUNCTION_soft' if not.
+#define switching_function(FUNCTION) \
+ struct switch_caller FUNCTION = \
+ { \
+ JSR, (__ptr_t) __68881_switch, \
+ __CONCAT(__CONCAT(__,FUNCTION),_soft), \
+ __CONCAT(__CONCAT(__,FUNCTION),_68881) \
+ }
+
+
+#endif /* 68881-switch.h */