[PATCH] libgloss: arm: break newlib dependency

[Richard Earnshaw]

On 14/12/2022 09:13, Mike Frysinger wrote:
> The libgloss port has been reaching back into newlib internals for a
> single header whose contents have been frozen for almost a decade.
> To break this backwards libgloss->newlib dependency, duplicate that
> header here so we can keep libgloss independent as it's meant to be.

This isn't really 'newlib internals', it's a header file that tries to 
provide ACLE[1] compatibility for older versions of GCC that lacked such 
support.  Having two copies of this is a maintenance burden, so I'm not 
entirely sure this is a great thing to do, even if the copies are 
supposed to be identical.

If we can agree on a common location in the source tree that both newlib 
and libgloss can pull this from, then I'm happy to move it if that would 
make you happier.

R.

[1] https://arm-software.github.io/acle/main/

> ---
>   libgloss/arm/Makefile.in   |   2 -
>   libgloss/arm/acle-compat.h | 182 +++++++++++++++++++++++++++++++++++++
>   2 files changed, 182 insertions(+), 2 deletions(-)
>   create mode 100644 libgloss/arm/acle-compat.h
> 
> diff --git a/libgloss/arm/Makefile.in b/libgloss/arm/Makefile.in
> index 06fae10c1fca..d0d5ea89d62e 100644
> --- a/libgloss/arm/Makefile.in
> +++ b/libgloss/arm/Makefile.in
> @@ -97,8 +97,6 @@ IQ80310_INSTALL	= install-iq80310
>   # Host specific makefile fragment comes in here.
>   @host_makefile_frag@
>   
> -INCLUDES += `if [ -d ${objroot}/newlib ]; then echo -I$(srcroot)/newlib/libc/machine/arm; fi`
> -
>   #
>   # build a test program for each target board. Just trying to get
>   # it to link is a good test, so we ignore all the errors for now.
> diff --git a/libgloss/arm/acle-compat.h b/libgloss/arm/acle-compat.h
> new file mode 100644
> index 000000000000..888ae2ea8afb
> --- /dev/null
> +++ b/libgloss/arm/acle-compat.h
> @@ -0,0 +1,182 @@
> +/*
> + * Copyright (c) 2014 ARM Ltd
> + * All rights reserved.
> + *
> + * Redistribution and use in source and binary forms, with or without
> + * modification, are permitted provided that the following conditions
> + * are met:
> + * 1. Redistributions of source code must retain the above copyright
> + *    notice, this list of conditions and the following disclaimer.
> + * 2. Redistributions in binary form must reproduce the above copyright
> + *    notice, this list of conditions and the following disclaimer in the
> + *    documentation and/or other materials provided with the distribution.
> + * 3. The name of the company may not be used to endorse or promote
> + *    products derived from this software without specific prior written
> + *    permission.
> + *
> + * THIS SOFTWARE IS PROVIDED BY ARM LTD ``AS IS'' AND ANY EXPRESS OR IMPLIED
> + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
> + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
> + * IN NO EVENT SHALL ARM LTD BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
> + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
> + * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
> + * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
> + * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
> + * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
> + * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> + */
> +
> +#ifndef __ARM_ARCH
> +
> +/* ACLE standardises a set of pre-defines that describe the ARM architecture.
> +   These were mostly implemented in GCC around GCC-4.8; older versions
> +   have no, or only partial support.  To provide a level of backwards
> +   compatibility we try to work out what the definitions should be, given
> +   the older pre-defines that GCC did produce.  This isn't complete, but
> +   it should be enough for use by routines that depend on this header.  */
> +
> +/* No need to handle ARMv8, GCC had ACLE support before that.  */
> +
> +# ifdef __ARM_ARCH_7__
> +/* The common subset of ARMv7 in all profiles.  */
> +#  define __ARM_ARCH 7
> +#  define __ARM_ARCH_ISA_THUMB 2
> +#  define __ARM_FEATURE_CLZ
> +#  define __ARM_FEATURE_LDREX 7
> +#  define __ARM_FEATURE_UNALIGNED
> +# endif
> +
> +# if defined (__ARM_ARCH_7A__) || defined (__ARM_ARCH_7R__)
> +#  define __ARM_ARCH 7
> +#  define __ARM_ARCH_ISA_THUMB 2
> +#  define __ARM_ARCH_ISA_ARM
> +#  define __ARM_FEATURE_CLZ
> +#  define __ARM_FEATURE_SIMD32
> +#  define __ARM_FEATURE_DSP
> +#  define __ARM_FEATURE_QBIT
> +#  define __ARM_FEATURE_SAT
> +#  define __ARM_FEATURE_LDREX 15
> +#  define __ARM_FEATURE_UNALIGNED
> +#  ifdef __ARM_ARCH_7A__
> +#   define __ARM_ARCH_PROFILE 'A'
> +#  else
> +#   define __ARM_ARCH_PROFILE 'R'
> +#  endif
> +# endif
> +
> +# ifdef __ARM_ARCH_7EM__
> +#  define __ARM_ARCH 7
> +#  define __ARM_ARCH_ISA_THUMB 2
> +#  define __ARM_FEATURE_CLZ
> +#  define __ARM_FEATURE_SIMD32
> +#  define __ARM_FEATURE_DSP
> +#  define __ARM_FEATURE_QBIT
> +#  define __ARM_FEATURE_SAT
> +#  define __ARM_FEATURE_LDREX 7
> +#  define __ARM_FEATURE_UNALIGNED
> +#  define __ARM_ARCH_PROFILE 'M'
> +# endif
> +
> +# ifdef __ARM_ARCH_7M__
> +#  define __ARM_ARCH 7
> +#  define __ARM_ARCH_ISA_THUMB 2
> +#  define __ARM_FEATURE_CLZ
> +#  define __ARM_FEATURE_QBIT
> +#  define __ARM_FEATURE_SAT
> +#  define __ARM_FEATURE_LDREX 7
> +#  define __ARM_FEATURE_UNALIGNED
> +#  define __ARM_ARCH_PROFILE 'M'
> +# endif
> +
> +# ifdef __ARM_ARCH_6T2__
> +#  define __ARM_ARCH 6
> +#  define __ARM_ARCH_ISA_THUMB 2
> +#  define __ARM_ARCH_ISA_ARM
> +#  define __ARM_FEATURE_CLZ
> +#  define __ARM_FEATURE_SIMD32
> +#  define __ARM_FEATURE_DSP
> +#  define __ARM_FEATURE_QBIT
> +#  define __ARM_FEATURE_SAT
> +#  define __ARM_FEATURE_LDREX 4
> +#  define __ARM_FEATURE_UNALIGNED
> +# endif
> +
> +# ifdef __ARM_ARCH_6M__
> +#  define __ARM_ARCH 6
> +#  define __ARM_ARCH_ISA_THUMB 1
> +#  define __ARM_ARCH_PROFILE 'M'
> +# endif
> +
> +# if defined (__ARM_ARCH_6__) || defined (__ARM_ARCH_6J__) \
> +  || defined (__ARM_ARCH_6K__) || defined (__ARM_ARCH_6Z__) \
> +  || defined (__ARM_ARCH_6ZK__)
> +#  define __ARM_ARCH 6
> +#  define __ARM_ARCH_ISA_THUMB 1
> +#  define __ARM_ARCH_ISA_ARM
> +#  define __ARM_FEATURE_CLZ
> +#  define __ARM_FEATURE_SIMD32
> +#  define __ARM_FEATURE_DSP
> +#  define __ARM_FEATURE_QBIT
> +#  define __ARM_FEATURE_SAT
> +#  define __ARM_FEATURE_UNALIGNED
> +#  ifndef __thumb__
> +#   if defined (__ARM_ARCH_6K__) || defined (__ARM_ARCH_6ZK__)
> +#    define __ARM_FEATURE_LDREX 15
> +#   else
> +#    define __ARM_FEATURE_LDREX 4
> +#   endif
> +#  endif
> +# endif
> +
> +# if defined (__ARM_ARCH_5TE__) || defined (__ARM_ARCH_5E__)
> +#  define __ARM_ARCH 5
> +#  define __ARM_ARCH_ISA_ARM
> +#  ifdef __ARM_ARCH_5TE__
> +#   define __ARM_ARCH_ISA_THUMB 1
> +#  endif
> +#  define __ARM_FEATURE_CLZ
> +#  define __ARM_FEATURE_DSP
> +# endif
> +
> +# if defined (__ARM_ARCH_5T__) || defined (__ARM_ARCH_5__)
> +#  define __ARM_ARCH 5
> +#  define __ARM_ARCH_ISA_ARM
> +#  ifdef __ARM_ARCH_5TE__
> +#   define __ARM_ARCH_ISA_THUMB 1
> +#  endif
> +#  define __ARM_FEATURE_CLZ
> +# endif
> +
> +# ifdef __ARM_ARCH_4T__
> +#  define __ARM_ARCH 4
> +#  define __ARM_ARCH_ISA_ARM
> +#  define __ARM_ARCH_ISA_THUMB 1
> +# endif
> +
> +# ifdef __ARM_ARCH_4__
> +#  define __ARM_ARCH 4
> +#  define __ARM_ARCH_ISA_ARM
> +# endif
> +
> +# if defined (__ARM_ARCH_3__) || defined (__ARM_ARCH_3M__)
> +#  define __ARM_ARCH 3
> +#  define __ARM_ARCH_ISA_ARM
> +# endif
> +
> +# ifdef __ARM_ARCH_2__
> +#  define __ARM_ARCH 2
> +#  define __ARM_ARCH_ISA_ARM
> +# endif
> +
> +# ifdef __ARMEB__
> +#  define __ARM_BIG_ENDIAN
> +# endif
> +
> +/* If we still don't know what the target architecture is, then we're
> +   probably not using GCC.  */
> +# ifndef __ARM_ARCH
> +#  error Unable to determine architecture version.
> +# endif
> +
> +#endif /* __ARM_ARCH  */
> +