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authorZack Weinberg <zackw@panix.com>2017-06-08 15:39:03 -0400
committerZack Weinberg <zackw@panix.com>2017-06-08 15:39:03 -0400
commit5046dbb4a7eba5eccfd258f92f4735c9ffc8d069 (patch)
tree4470480d904b65cf14ca524f96f79eca818c3eaf /REORG.TODO/sysdeps/arm/arm-features.h
parent199fc19d3aaaf57944ef036e15904febe877fc93 (diff)
downloadglibc-zack/build-layout-experiment.tar.gz
glibc-zack/build-layout-experiment.tar.xz
glibc-zack/build-layout-experiment.zip
Prepare for radical source tree reorganization. zack/build-layout-experiment
All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).
Diffstat (limited to 'REORG.TODO/sysdeps/arm/arm-features.h')
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diff --git a/REORG.TODO/sysdeps/arm/arm-features.h b/REORG.TODO/sysdeps/arm/arm-features.h
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+++ b/REORG.TODO/sysdeps/arm/arm-features.h
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+/* Macros to test for CPU features on ARM.  Generic ARM version.
+   Copyright (C) 2012-2017 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 */