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authorJoseph Myers <joseph@codesourcery.com>2014-02-08 01:49:39 +0000
committerJoseph Myers <joseph@codesourcery.com>2014-02-08 01:49:39 +0000
commitc6bfe5c4d756913297db03f55e42016d1c48918c (patch)
tree898d2910ef903f46b596ad54e519ed4495357766 /sysdeps/arm/arm-features.h
parent852fa2dd3aa1a687780e27300df9eb0bdc433863 (diff)
Move arm from ports to libc.
I've moved the ARM port from ports to the main sysdeps hierarchy. Beyond the README update, the move of the files was simply git mv ports/sysdeps/arm sysdeps/arm git mv ports/sysdeps/unix/arm sysdeps/unix/arm git mv ports/sysdeps/unix/sysv/linux/arm sysdeps/unix/sysv/linux/arm and in addition to the ChangeLog entries here, I put a note at the top of ports/ChangeLog.arm similar to that at the top of ChangeLog.powerpc. There is deliberately no NEWS change, as I think it makes the most sense to put in a general note above all ports having moved if we can achieve that for 2.20. Tested that disassembly of installed shared libraries for arm is the same before and after this patch, except for data (not instructions) in ld.so (there are assertions in sysdeps/arm/dl-machine.h, and the path by which that file is found, and so by which it appears in the assertion message, changes as a result of the move). * sysdeps/arm: Move directory from ports/sysdeps/arm. * sysdeps/unix/arm: Move directory from ports/sysdeps/unix/arm. * sysdeps/unix/sysv/linux/arm: Move directory from ports/sysdeps/unix/sysv/linux/arm. * README: Update listing for arm-*-linux-gnueabi. ports/ChangeLog.arm: * sysdeps/arm: Move directory to ../sysdeps/arm. * sysdeps/unix/arm: Move directory to ../sysdeps.arm. * sysdeps/unix/sysv/linux/arm: Move directory to ../sysdeps/unix/sysv/linux/arm.
Diffstat (limited to 'sysdeps/arm/arm-features.h')
-rw-r--r--sysdeps/arm/arm-features.h59
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 */