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115 lines
3.7 KiB
C
115 lines
3.7 KiB
C
/* FPU control word definitions. PowerPC version.
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Copyright (C) 1996-2023 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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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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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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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, see
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<https://www.gnu.org/licenses/>. */
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#ifndef _FPU_CONTROL_H
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#define _FPU_CONTROL_H
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#if defined __SPE__ || (defined __NO_FPRS__ && !defined _SOFT_FLOAT)
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# error "SPE/e500 is no longer supported"
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#endif
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#ifdef _SOFT_FLOAT
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# define _FPU_RESERVED 0xffffffff
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# define _FPU_DEFAULT 0x00000000 /* Default value. */
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typedef unsigned int fpu_control_t;
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# define _FPU_GETCW(cw) (cw) = 0
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# define _FPU_SETCW(cw) (void) (cw)
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extern fpu_control_t __fpu_control;
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#else /* PowerPC 6xx floating-point. */
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/* rounding control */
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# define _FPU_RC_NEAREST 0x00 /* RECOMMENDED */
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# define _FPU_RC_DOWN 0x03
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# define _FPU_RC_UP 0x02
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# define _FPU_RC_ZERO 0x01
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# define _FPU_MASK_RC (_FPU_RC_NEAREST|_FPU_RC_DOWN|_FPU_RC_UP|_FPU_RC_ZERO)
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# define _FPU_MASK_NI 0x04 /* non-ieee mode */
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/* masking of interrupts */
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# define _FPU_MASK_ZM 0x10 /* zero divide */
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# define _FPU_MASK_OM 0x40 /* overflow */
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# define _FPU_MASK_UM 0x20 /* underflow */
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# define _FPU_MASK_XM 0x08 /* inexact */
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# define _FPU_MASK_IM 0x80 /* invalid operation */
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# define _FPU_RESERVED 0xffffff00 /* These bits are reserved are not changed. */
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/* The fdlibm code requires no interrupts for exceptions. */
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# define _FPU_DEFAULT 0x00000000 /* Default value. */
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/* IEEE: same as above, but (some) exceptions;
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we leave the 'inexact' exception off.
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*/
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# define _FPU_IEEE 0x000000f0
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/* Type of the control word. */
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typedef unsigned int fpu_control_t;
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/* Macros for accessing the hardware control word. */
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# define _FPU_GETCW(cw) \
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({union { double __d; unsigned long long __ll; } __u; \
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__asm__ __volatile__("mffs %0" : "=f" (__u.__d)); \
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(cw) = (fpu_control_t) __u.__ll; \
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(fpu_control_t) __u.__ll; \
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})
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# define _FPU_GET_RC_ISA300() \
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({union { double __d; unsigned long long __ll; } __u; \
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__asm__ __volatile__( \
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".machine push; .machine \"power9\"; mffsl %0; .machine pop" \
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: "=f" (__u.__d)); \
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(fpu_control_t) (__u.__ll & _FPU_MASK_RC); \
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})
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# ifdef _ARCH_PWR9
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# define _FPU_GET_RC() _FPU_GET_RC_ISA300()
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# elif defined __BUILTIN_CPU_SUPPORTS__
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# define _FPU_GET_RC() \
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({fpu_control_t __rc; \
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__rc = __glibc_likely (__builtin_cpu_supports ("arch_3_00")) \
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? _FPU_GET_RC_ISA300 () \
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: _FPU_GETCW (__rc) & _FPU_MASK_RC; \
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__rc; \
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})
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# else
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# define _FPU_GET_RC() \
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({fpu_control_t __rc = _FPU_GETCW (__rc) & _FPU_MASK_RC; \
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__rc; \
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})
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# endif
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# define _FPU_SETCW(cw) \
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{ union { double __d; unsigned long long __ll; } __u; \
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register double __fr; \
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__u.__ll = 0xfff80000LL << 32; /* This is a QNaN. */ \
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__u.__ll |= (cw) & 0xffffffffLL; \
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__fr = __u.__d; \
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__asm__ __volatile__("mtfsf 255,%0" : : "f" (__fr)); \
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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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#endif /* PowerPC 6xx floating-point. */
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#endif /* _FPU_CONTROL_H */
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