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44 lines
1.7 KiB
C
44 lines
1.7 KiB
C
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/* Store current floating-point environment.
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Copyright (C) 2000 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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Contributed by Denis Joseph Barrow (djbarrow@de.ibm.com).
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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 Library General Public License as
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published by the Free Software Foundation; either version 2 of the
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License, or (at your option) any later version.
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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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Library General Public License for more details.
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You should have received a copy of the GNU Library General Public
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License along with the GNU C Library; see the file COPYING.LIB. If not,
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write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA. */
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#include <fenv_libc.h>
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#include <fpu_control.h>
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#include <stddef.h>
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#include <asm/ptrace.h>
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#include <sys/ptrace.h>
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#include <unistd.h>
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int
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fegetenv (fenv_t *envp)
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{
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/* The S/390 IEEE fpu doesn't keep track of the ieee instruction pointer.
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To get around that the kernel will store the address of the last
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fpu fault to the process structure. This ptrace call reads this value
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from the kernel space. That means the ieee_instruction_pointer is
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only correct after a fpu fault. That's the best we can do, there is
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no way to find out the ieee instruction pointer if there was no fault. */
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_FPU_GETCW (envp->fpc);
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envp->ieee_instruction_pointer =
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ptrace (PTRACE_PEEKUSER, getpid (), PT_IEEE_IP);
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/* Success. */
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return 0;
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}
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