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Diffstat (limited to 'sysdeps/arm/arm-features.h')
-rw-r--r-- | sysdeps/arm/arm-features.h | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/sysdeps/arm/arm-features.h b/sysdeps/arm/arm-features.h new file mode 100644 index 0000000000..b743756519 --- /dev/null +++ b/sysdeps/arm/arm-features.h @@ -0,0 +1,59 @@ +/* Macros to test for CPU features on ARM. Generic ARM version. + Copyright (C) 2012-2014 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, see + <http://www.gnu.org/licenses/>. */ + +#ifndef _ARM_ARM_FEATURES_H +#define _ARM_ARM_FEATURES_H 1 + +/* An OS-specific arm-features.h file should define ARM_HAVE_VFP to + an appropriate expression for testing at runtime whether the VFP + hardware is present. We'll then redefine it to a constant if we + know at compile time that we can assume VFP. */ + +#ifndef __SOFTFP__ +/* The compiler is generating VFP instructions, so we're already + assuming the hardware exists. */ +# undef ARM_HAVE_VFP +# define ARM_HAVE_VFP 1 +#endif + +/* An OS-specific arm-features.h file may define ARM_ASSUME_NO_IWMMXT + to indicate at compile time that iWMMXt hardware is never present + at runtime (or that we never care about its state) and so need not + be checked for. */ + +/* A more-specific arm-features.h file may define ARM_ALWAYS_BX to indicate + that instructions using pc as a destination register must never be used, + so a "bx" (or "blx") instruction is always required. */ + +/* The log2 of the minimum alignment required for an address that + is the target of a computed branch (i.e. a "bx" instruction). + A more-specific arm-features.h file may define this to set a more + stringent requirement. + + Using this only makes sense for code in ARM mode (where instructions + always have a fixed size of four bytes), or for Thumb-mode code that is + specifically aligning all the related branch targets to match (since + Thumb instructions might be either two or four bytes). */ +#ifndef ARM_BX_ALIGN_LOG2 +# define ARM_BX_ALIGN_LOG2 2 +#endif + +/* An OS-specific arm-features.h file may define ARM_NO_INDEX_REGISTER to + indicate that the two-register addressing modes must never be used. */ + +#endif /* arm-features.h */ |