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60 lines
2.5 KiB
C
60 lines
2.5 KiB
C
/* Macros to test for CPU features on ARM. Generic ARM version.
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Copyright (C) 2012-2017 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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<http://www.gnu.org/licenses/>. */
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#ifndef _ARM_ARM_FEATURES_H
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#define _ARM_ARM_FEATURES_H 1
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/* An OS-specific arm-features.h file should define ARM_HAVE_VFP to
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an appropriate expression for testing at runtime whether the VFP
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hardware is present. We'll then redefine it to a constant if we
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know at compile time that we can assume VFP. */
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#ifndef __SOFTFP__
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/* The compiler is generating VFP instructions, so we're already
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assuming the hardware exists. */
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# undef ARM_HAVE_VFP
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# define ARM_HAVE_VFP 1
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#endif
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/* An OS-specific arm-features.h file may define ARM_ASSUME_NO_IWMMXT
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to indicate at compile time that iWMMXt hardware is never present
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at runtime (or that we never care about its state) and so need not
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be checked for. */
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/* A more-specific arm-features.h file may define ARM_ALWAYS_BX to indicate
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that instructions using pc as a destination register must never be used,
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so a "bx" (or "blx") instruction is always required. */
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/* The log2 of the minimum alignment required for an address that
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is the target of a computed branch (i.e. a "bx" instruction).
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A more-specific arm-features.h file may define this to set a more
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stringent requirement.
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Using this only makes sense for code in ARM mode (where instructions
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always have a fixed size of four bytes), or for Thumb-mode code that is
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specifically aligning all the related branch targets to match (since
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Thumb instructions might be either two or four bytes). */
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#ifndef ARM_BX_ALIGN_LOG2
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# define ARM_BX_ALIGN_LOG2 2
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#endif
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/* An OS-specific arm-features.h file may define ARM_NO_INDEX_REGISTER to
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indicate that the two-register addressing modes must never be used. */
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#endif /* arm-features.h */
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