Reorganize memcpy selection.

This patch cleans up the auto configury mechanism used to select
different implementations of memcpy for various architecture versions.

The approach here is to remove the selection of memcpy within automake
and instead use complimentary logic in memcpy-stub.c and memcpy.S to
choose between the generic memcpy.c implemenation or one of the
architecture specific memcpy*.S implemenations.

Regressed for armv7-a armv5 armv8-a, correct selection of memcpy
implementation by manual inspection of a test program built for these
three architectures.

This revised patch flips the remaining preprocessor logic in
memcpy-stub.c to use ACLE defines as requested in the previous review
and removes the now disused HAVE_ARMV7A and HAVE_ARMV8A configure.in
support.

7 files changed, 92 insertions, 296 deletions

diff --git a/newlib/ChangeLog b/newlib/ChangeLog
index f8e51a78a..fac2fdb04 100644
--- a/newlib/ChangeLog
+++ b/newlib/ChangeLog
@@ -1,3 +1,14 @@
+2015-11-06  Marcus Shawcroft  <marcus.shawcroft@arm.com>
+
+	* libc/machine/arm/Makefile.am: Drop MEMCPY_SRC and MEMCPY_OBJ.
+	* libc/machine/arm/Makefile.in: Regenerate.
+	* libc/machine/arm/configure.in: Remove HAVE_ARMV8A, HAVE_ARMV7A and
+	HAVE_ARM7M.
+	* libc/machine/arm/configure: Regenerate.
+	* libc/machine/arm/memcpy-stub.c: New.
+	* libc/machine/arm/memcpy.c: Adjust copyright year.  Adjust comments.
+	Include acle-compat.h.
+
 2015-11-06  Olivier Martin  <olivier@labapart.com>
 
 	* libc/include/stdlib.h (mktemp): Change attribute to deprecated.
diff --git a/newlib/libc/machine/arm/Makefile.am b/newlib/libc/machine/arm/Makefile.am
index 0eb1cf12f..70afdf140 100644
--- a/newlib/libc/machine/arm/Makefile.am
+++ b/newlib/libc/machine/arm/Makefile.am
@@ -29,39 +29,19 @@ MEMCHR_SRC=
 MEMCHR_OBJ=
 endif
 
-if OPT_SIZE
-MEMCPY_SRC=
-MEMCPY_OBJ=
-else
-if HAVE_ARMV8A
-MEMCPY_SRC=memcpy.S
-MEMCPY_OBJ=$(lpfx)memcpy.o
-else
-if HAVE_ARMV7A
-MEMCPY_SRC=memcpy.S
-MEMCPY_OBJ=$(lpfx)memcpy.o
-else
-if HAVE_ARMV7M
-MEMCPY_SRC=memcpy.S
-MEMCPY_OBJ=$(lpfx)memcpy.o
-else
-MEMCPY_SRC=
-MEMCPY_OBJ=
-endif !HAVE_ARMV7M
-endif !HAVE_ARMV7A
-endif !HAVE_ARMV8A
-endif !OPT_SIZE
-
 lib_a_SOURCES = setjmp.S access.c strcmp.S strcpy.c \
-	        $(MEMCPY_SRC) $(MEMCHR_SRC) $(STRLEN_SRC) \
+		$(MEMCHR_SRC) $(STRLEN_SRC) \
 		strlen-armv7.S aeabi_memcpy.c aeabi_memcpy-armv7a.S \
 		aeabi_memmove.c aeabi_memmove-soft.S \
 		aeabi_memset.c aeabi_memset-soft.S aeabi_memclr.c
+lib_a_SOURCES += memcpy-stub.c
+lib_a_SOURCES += memcpy.S
 
 lib_a_CCASFLAGS=$(AM_CCASFLAGS)
 lib_a_CFLAGS = $(AM_CFLAGS)
-lib_a_LIBADD = $(STRLEN_OBJ) $(MEMCHR_OBJ) $(MEMCPY_OBJ)
-lib_a_DEPENDENCIES = $(STRLEN_OBJ) $(MEMCHR_OBJ) $(MEMCPY_OBJ)
+lib_a_LIBADD = $(STRLEN_OBJ) $(MEMCHR_OBJ)
+
+lib_a_DEPENDENCIES = $(STRLEN_OBJ) $(MEMCHR_OBJ)
 
 ACLOCAL_AMFLAGS = -I ../../.. -I ../../../..
 CONFIG_STATUS_DEPENDENCIES = $(newlib_basedir)/configure.host
diff --git a/newlib/libc/machine/arm/Makefile.in b/newlib/libc/machine/arm/Makefile.in
index 81dea3099..8b69c1207 100644
--- a/newlib/libc/machine/arm/Makefile.in
+++ b/newlib/libc/machine/arm/Makefile.in
@@ -71,27 +71,20 @@ lib_a_AR = $(AR) $(ARFLAGS)
 @HAVE_THUMB1_FALSE@am__DEPENDENCIES_1 = $(lpfx)strlen.o
 @HAVE_THUMB1_TRUE@@OPT_SIZE_TRUE@am__DEPENDENCIES_1 = $(lpfx)strlen.o
 @HAVE_ARMV7_TRUE@am__DEPENDENCIES_2 = $(lpfx)memchr.o
-@HAVE_ARMV7A_FALSE@@HAVE_ARMV7M_TRUE@@HAVE_ARMV8A_FALSE@@OPT_SIZE_FALSE@am__DEPENDENCIES_3 = $(lpfx)memcpy.o
-@HAVE_ARMV7A_TRUE@@HAVE_ARMV8A_FALSE@@OPT_SIZE_FALSE@am__DEPENDENCIES_3 = $(lpfx)memcpy.o
-@HAVE_ARMV8A_TRUE@@OPT_SIZE_FALSE@am__DEPENDENCIES_3 =  \
-@HAVE_ARMV8A_TRUE@@OPT_SIZE_FALSE@	$(lpfx)memcpy.o
-@HAVE_ARMV7A_FALSE@@HAVE_ARMV7M_TRUE@@HAVE_ARMV8A_FALSE@@OPT_SIZE_FALSE@am__objects_1 = lib_a-memcpy.$(OBJEXT)
-@HAVE_ARMV7A_TRUE@@HAVE_ARMV8A_FALSE@@OPT_SIZE_FALSE@am__objects_1 = lib_a-memcpy.$(OBJEXT)
-@HAVE_ARMV8A_TRUE@@OPT_SIZE_FALSE@am__objects_1 =  \
-@HAVE_ARMV8A_TRUE@@OPT_SIZE_FALSE@	lib_a-memcpy.$(OBJEXT)
-@HAVE_ARMV7_TRUE@am__objects_2 = lib_a-memchr.$(OBJEXT)
-@HAVE_THUMB1_FALSE@am__objects_3 = lib_a-strlen.$(OBJEXT)
-@HAVE_THUMB1_TRUE@@OPT_SIZE_TRUE@am__objects_3 =  \
+@HAVE_ARMV7_TRUE@am__objects_1 = lib_a-memchr.$(OBJEXT)
+@HAVE_THUMB1_FALSE@am__objects_2 = lib_a-strlen.$(OBJEXT)
+@HAVE_THUMB1_TRUE@@OPT_SIZE_TRUE@am__objects_2 =  \
 @HAVE_THUMB1_TRUE@@OPT_SIZE_TRUE@	lib_a-strlen.$(OBJEXT)
 am_lib_a_OBJECTS = lib_a-setjmp.$(OBJEXT) lib_a-access.$(OBJEXT) \
 	lib_a-strcmp.$(OBJEXT) lib_a-strcpy.$(OBJEXT) $(am__objects_1) \
-	$(am__objects_2) $(am__objects_3) lib_a-strlen-armv7.$(OBJEXT) \
+	$(am__objects_2) lib_a-strlen-armv7.$(OBJEXT) \
 	lib_a-aeabi_memcpy.$(OBJEXT) \
 	lib_a-aeabi_memcpy-armv7a.$(OBJEXT) \
 	lib_a-aeabi_memmove.$(OBJEXT) \
 	lib_a-aeabi_memmove-soft.$(OBJEXT) \
 	lib_a-aeabi_memset.$(OBJEXT) lib_a-aeabi_memset-soft.$(OBJEXT) \
-	lib_a-aeabi_memclr.$(OBJEXT)
+	lib_a-aeabi_memclr.$(OBJEXT) lib_a-memcpy-stub.$(OBJEXT) \
+	lib_a-memcpy.$(OBJEXT)
 lib_a_OBJECTS = $(am_lib_a_OBJECTS)
 DEFAULT_INCLUDES = -I.@am__isrc@
 depcomp =
@@ -228,26 +221,15 @@ noinst_LIBRARIES = lib.a
 @HAVE_ARMV7_TRUE@MEMCHR_SRC = memchr.S
 @HAVE_ARMV7_FALSE@MEMCHR_OBJ = 
 @HAVE_ARMV7_TRUE@MEMCHR_OBJ = $(lpfx)memchr.o
-@HAVE_ARMV7A_FALSE@@HAVE_ARMV7M_FALSE@@HAVE_ARMV8A_FALSE@@OPT_SIZE_FALSE@MEMCPY_SRC = 
-@HAVE_ARMV7A_FALSE@@HAVE_ARMV7M_TRUE@@HAVE_ARMV8A_FALSE@@OPT_SIZE_FALSE@MEMCPY_SRC = memcpy.S
-@HAVE_ARMV7A_TRUE@@HAVE_ARMV8A_FALSE@@OPT_SIZE_FALSE@MEMCPY_SRC = memcpy.S
-@HAVE_ARMV8A_TRUE@@OPT_SIZE_FALSE@MEMCPY_SRC = memcpy.S
-@OPT_SIZE_TRUE@MEMCPY_SRC = 
-@HAVE_ARMV7A_FALSE@@HAVE_ARMV7M_FALSE@@HAVE_ARMV8A_FALSE@@OPT_SIZE_FALSE@MEMCPY_OBJ = 
-@HAVE_ARMV7A_FALSE@@HAVE_ARMV7M_TRUE@@HAVE_ARMV8A_FALSE@@OPT_SIZE_FALSE@MEMCPY_OBJ = $(lpfx)memcpy.o
-@HAVE_ARMV7A_TRUE@@HAVE_ARMV8A_FALSE@@OPT_SIZE_FALSE@MEMCPY_OBJ = $(lpfx)memcpy.o
-@HAVE_ARMV8A_TRUE@@OPT_SIZE_FALSE@MEMCPY_OBJ = $(lpfx)memcpy.o
-@OPT_SIZE_TRUE@MEMCPY_OBJ = 
-lib_a_SOURCES = setjmp.S access.c strcmp.S strcpy.c \
-	        $(MEMCPY_SRC) $(MEMCHR_SRC) $(STRLEN_SRC) \
-		strlen-armv7.S aeabi_memcpy.c aeabi_memcpy-armv7a.S \
-		aeabi_memmove.c aeabi_memmove-soft.S \
-		aeabi_memset.c aeabi_memset-soft.S aeabi_memclr.c
-
+lib_a_SOURCES = setjmp.S access.c strcmp.S strcpy.c $(MEMCHR_SRC) \
+	$(STRLEN_SRC) strlen-armv7.S aeabi_memcpy.c \
+	aeabi_memcpy-armv7a.S aeabi_memmove.c aeabi_memmove-soft.S \
+	aeabi_memset.c aeabi_memset-soft.S aeabi_memclr.c \
+	memcpy-stub.c memcpy.S
 lib_a_CCASFLAGS = $(AM_CCASFLAGS)
 lib_a_CFLAGS = $(AM_CFLAGS)
-lib_a_LIBADD = $(STRLEN_OBJ) $(MEMCHR_OBJ) $(MEMCPY_OBJ)
-lib_a_DEPENDENCIES = $(STRLEN_OBJ) $(MEMCHR_OBJ) $(MEMCPY_OBJ)
+lib_a_LIBADD = $(STRLEN_OBJ) $(MEMCHR_OBJ)
+lib_a_DEPENDENCIES = $(STRLEN_OBJ) $(MEMCHR_OBJ)
 ACLOCAL_AMFLAGS = -I ../../.. -I ../../../..
 CONFIG_STATUS_DEPENDENCIES = $(newlib_basedir)/configure.host
 MEMCPY_DEP = memcpy-armv7a.S memcpy-armv7m.S
@@ -330,12 +312,6 @@ lib_a-strcmp.o: strcmp.S
 lib_a-strcmp.obj: strcmp.S
 	$(CCAS) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CCASFLAGS) $(CCASFLAGS) -c -o lib_a-strcmp.obj `if test -f 'strcmp.S'; then $(CYGPATH_W) 'strcmp.S'; else $(CYGPATH_W) '$(srcdir)/strcmp.S'; fi`
 
-lib_a-memcpy.o: memcpy.S
-	$(CCAS) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CCASFLAGS) $(CCASFLAGS) -c -o lib_a-memcpy.o `test -f 'memcpy.S' || echo '$(srcdir)/'`memcpy.S
-
-lib_a-memcpy.obj: memcpy.S
-	$(CCAS) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CCASFLAGS) $(CCASFLAGS) -c -o lib_a-memcpy.obj `if test -f 'memcpy.S'; then $(CYGPATH_W) 'memcpy.S'; else $(CYGPATH_W) '$(srcdir)/memcpy.S'; fi`
-
 lib_a-memchr.o: memchr.S
 	$(CCAS) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CCASFLAGS) $(CCASFLAGS) -c -o lib_a-memchr.o `test -f 'memchr.S' || echo '$(srcdir)/'`memchr.S
 
@@ -366,6 +342,12 @@ lib_a-aeabi_memset-soft.o: aeabi_memset-soft.S
 lib_a-aeabi_memset-soft.obj: aeabi_memset-soft.S
 	$(CCAS) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CCASFLAGS) $(CCASFLAGS) -c -o lib_a-aeabi_memset-soft.obj `if test -f 'aeabi_memset-soft.S'; then $(CYGPATH_W) 'aeabi_memset-soft.S'; else $(CYGPATH_W) '$(srcdir)/aeabi_memset-soft.S'; fi`
 
+lib_a-memcpy.o: memcpy.S
+	$(CCAS) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CCASFLAGS) $(CCASFLAGS) -c -o lib_a-memcpy.o `test -f 'memcpy.S' || echo '$(srcdir)/'`memcpy.S
+
+lib_a-memcpy.obj: memcpy.S
+	$(CCAS) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CCASFLAGS) $(CCASFLAGS) -c -o lib_a-memcpy.obj `if test -f 'memcpy.S'; then $(CYGPATH_W) 'memcpy.S'; else $(CYGPATH_W) '$(srcdir)/memcpy.S'; fi`
+
 .c.o:
 	$(COMPILE) -c $<
 
@@ -414,6 +396,12 @@ lib_a-aeabi_memclr.o: aeabi_memclr.c
 lib_a-aeabi_memclr.obj: aeabi_memclr.c
 	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-aeabi_memclr.obj `if test -f 'aeabi_memclr.c'; then $(CYGPATH_W) 'aeabi_memclr.c'; else $(CYGPATH_W) '$(srcdir)/aeabi_memclr.c'; fi`
 
+lib_a-memcpy-stub.o: memcpy-stub.c
+	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-memcpy-stub.o `test -f 'memcpy-stub.c' || echo '$(srcdir)/'`memcpy-stub.c
+
+lib_a-memcpy-stub.obj: memcpy-stub.c
+	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-memcpy-stub.obj `if test -f 'memcpy-stub.c'; then $(CYGPATH_W) 'memcpy-stub.c'; else $(CYGPATH_W) '$(srcdir)/memcpy-stub.c'; fi`
+
 ID: $(HEADERS) $(SOURCES) $(LISP) $(TAGS_FILES)
 	list='$(SOURCES) $(HEADERS) $(LISP) $(TAGS_FILES)'; \
 	unique=`for i in $$list; do \
diff --git a/newlib/libc/machine/arm/configure b/newlib/libc/machine/arm/configure
index 9f82c7f22..eb6236111 100755
--- a/newlib/libc/machine/arm/configure
+++ b/newlib/libc/machine/arm/configure
@@ -565,12 +565,6 @@ ac_unique_file="Makefile.am"
 ac_subst_vars='LTLIBOBJS
 LIBOBJS
 CFLAGS
-HAVE_ARMV7M_FALSE
-HAVE_ARMV7M_TRUE
-HAVE_ARMV8A_FALSE
-HAVE_ARMV8A_TRUE
-HAVE_ARMV7A_FALSE
-HAVE_ARMV7A_TRUE
 HAVE_ARMV7_FALSE
 HAVE_ARMV7_TRUE
 OPT_SIZE_FALSE
@@ -3549,132 +3543,6 @@ else
 fi
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether armv7a processor is supported" >&5
-$as_echo_n "checking whether armv7a processor is supported... " >&6; }
-if ${acnewlib_cv_armv7a_processor+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat > conftest.c <<EOF
-
-#if defined (__ARM_ARCH_7A__) && defined (__ARM_FEATURE_UNALIGNED)
-  #define HAVE_ARMV7A
- #else
-  #error "ARMV7A is not supported."
-#endif
-int main () {
-  return 0;
-}
-EOF
-if { ac_try='${CC} $CFLAGS $CPPFLAGS -c -o conftest.o conftest.c
-							1>&5'
-  { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
-  (eval $ac_try) 2>&5
-  ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
-  test $ac_status = 0; }; }
-then
-  acnewlib_cv_armv7a_processor=yes;
-else
-  acnewlib_cv_armv7a_processor=no;
-fi
-rm -f conftest*
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $acnewlib_cv_armv7a_processor" >&5
-$as_echo "$acnewlib_cv_armv7a_processor" >&6; }
-
- if test x"$acnewlib_cv_armv7a_processor" = x"yes"; then
-  HAVE_ARMV7A_TRUE=
-  HAVE_ARMV7A_FALSE='#'
-else
-  HAVE_ARMV7A_TRUE='#'
-  HAVE_ARMV7A_FALSE=
-fi
-
-
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether armv8a processor is supported" >&5
-$as_echo_n "checking whether armv8a processor is supported... " >&6; }
-if ${acnewlib_cv_armv8a_processor+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat > conftest.c <<EOF
-
-#if defined (__ARM_ARCH_8A__) && defined (__ARM_FEATURE_UNALIGNED)
-  #define HAVE_ARMV8A
- #else
-  #error "ARMV8A is not supported."
-#endif
-int main () {
-  return 0;
-}
-EOF
-if { ac_try='${CC} $CFLAGS $CPPFLAGS -c -o conftest.o conftest.c
-							1>&5'
-  { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
-  (eval $ac_try) 2>&5
-  ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
-  test $ac_status = 0; }; }
-then
-  acnewlib_cv_armv8a_processor=yes;
-else
-  acnewlib_cv_armv8a_processor=no;
-fi
-rm -f conftest*
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $acnewlib_cv_armv8a_processor" >&5
-$as_echo "$acnewlib_cv_armv8a_processor" >&6; }
-
- if test x"$acnewlib_cv_armv8a_processor" = x"yes"; then
-  HAVE_ARMV8A_TRUE=
-  HAVE_ARMV8A_FALSE='#'
-else
-  HAVE_ARMV8A_TRUE='#'
-  HAVE_ARMV8A_FALSE=
-fi
-
-
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether armv7m processor is supported" >&5
-$as_echo_n "checking whether armv7m processor is supported... " >&6; }
-if ${acnewlib_cv_armv7m_processor+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat > conftest.c <<EOF
-
-#if defined (__ARM_ARCH_7M__) || defined (__ARM_ARCH_7EM__)
-  #define HAVE_ARMV7M
- #else
-  #error "ARMV7M is not supported."
-#endif
-int main () {
-  return 0;
-}
-EOF
-if { ac_try='${CC} $CFLAGS $CPPFLAGS -c -o conftest.o conftest.c
-							1>&5'
-  { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
-  (eval $ac_try) 2>&5
-  ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
-  test $ac_status = 0; }; }
-then
-  acnewlib_cv_armv7m_processor=yes;
-else
-  acnewlib_cv_armv7m_processor=no;
-fi
-rm -f conftest*
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $acnewlib_cv_armv7m_processor" >&5
-$as_echo "$acnewlib_cv_armv7m_processor" >&6; }
-
- if test x"$acnewlib_cv_armv7m_processor" = x"yes"; then
-  HAVE_ARMV7M_TRUE=
-  HAVE_ARMV7M_FALSE='#'
-else
-  HAVE_ARMV7M_TRUE='#'
-  HAVE_ARMV7M_FALSE=
-fi
-
-
 
 
 ac_config_files="$ac_config_files Makefile"
@@ -3877,18 +3745,6 @@ if test -z "${HAVE_ARMV7_TRUE}" && test -z "${HAVE_ARMV7_FALSE}"; then
   as_fn_error $? "conditional \"HAVE_ARMV7\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
 fi
-if test -z "${HAVE_ARMV7A_TRUE}" && test -z "${HAVE_ARMV7A_FALSE}"; then
-  as_fn_error $? "conditional \"HAVE_ARMV7A\" was never defined.
-Usually this means the macro was only invoked conditionally." "$LINENO" 5
-fi
-if test -z "${HAVE_ARMV8A_TRUE}" && test -z "${HAVE_ARMV8A_FALSE}"; then
-  as_fn_error $? "conditional \"HAVE_ARMV8A\" was never defined.
-Usually this means the macro was only invoked conditionally." "$LINENO" 5
-fi
-if test -z "${HAVE_ARMV7M_TRUE}" && test -z "${HAVE_ARMV7M_FALSE}"; then
-  as_fn_error $? "conditional \"HAVE_ARMV7M\" was never defined.
-Usually this means the macro was only invoked conditionally." "$LINENO" 5
-fi
 
 : "${CONFIG_STATUS=./config.status}"
 ac_write_fail=0
diff --git a/newlib/libc/machine/arm/configure.in b/newlib/libc/machine/arm/configure.in
index 69fbe2b03..b76f731c8 100644
--- a/newlib/libc/machine/arm/configure.in
+++ b/newlib/libc/machine/arm/configure.in
@@ -86,81 +86,6 @@ rm -f conftest*])
 
 AM_CONDITIONAL(HAVE_ARMV7, test x"$acnewlib_cv_armv7_processor" = x"yes")
 
-dnl Check for whether ARM_ARCH_7A is defined.
-AC_CACHE_CHECK(whether armv7a processor is supported,
-	       acnewlib_cv_armv7a_processor, [dnl
-cat > conftest.c <<EOF
-
-#if defined (__ARM_ARCH_7A__) && defined (__ARM_FEATURE_UNALIGNED)
-  #define HAVE_ARMV7A
- #else
-  #error "ARMV7A is not supported."
-#endif
-int main () {
-  return 0;
-}
-EOF
-if AC_TRY_COMMAND([${CC} $CFLAGS $CPPFLAGS -c -o conftest.o conftest.c
-							1>&AS_MESSAGE_LOG_FD])
-then
-  acnewlib_cv_armv7a_processor=yes;
-else
-  acnewlib_cv_armv7a_processor=no;
-fi
-rm -f conftest*])
-
-AM_CONDITIONAL(HAVE_ARMV7A, test x"$acnewlib_cv_armv7a_processor" = x"yes")
-
-dnl Check for whether ARM_ARCH_8A is defined.
-AC_CACHE_CHECK(whether armv8a processor is supported,
-	       acnewlib_cv_armv8a_processor, [dnl
-cat > conftest.c <<EOF
-
-#if defined (__ARM_ARCH_8A__) && defined (__ARM_FEATURE_UNALIGNED)
-  #define HAVE_ARMV8A
- #else
-  #error "ARMV8A is not supported."
-#endif
-int main () {
-  return 0;
-}
-EOF
-if AC_TRY_COMMAND([${CC} $CFLAGS $CPPFLAGS -c -o conftest.o conftest.c
-							1>&AS_MESSAGE_LOG_FD])
-then
-  acnewlib_cv_armv8a_processor=yes;
-else
-  acnewlib_cv_armv8a_processor=no;
-fi
-rm -f conftest*])
-
-AM_CONDITIONAL(HAVE_ARMV8A, test x"$acnewlib_cv_armv8a_processor" = x"yes")
-
-dnl Check for whether ARM_ARCH_7M is defined.
-AC_CACHE_CHECK(whether armv7m processor is supported,
-	       acnewlib_cv_armv7m_processor, [dnl
-cat > conftest.c <<EOF
-
-#if defined (__ARM_ARCH_7M__) || defined (__ARM_ARCH_7EM__)
-  #define HAVE_ARMV7M
- #else
-  #error "ARMV7M is not supported."
-#endif
-int main () {
-  return 0;
-}
-EOF
-if AC_TRY_COMMAND([${CC} $CFLAGS $CPPFLAGS -c -o conftest.o conftest.c
-							1>&AS_MESSAGE_LOG_FD])
-then
-  acnewlib_cv_armv7m_processor=yes;
-else
-  acnewlib_cv_armv7m_processor=no;
-fi
-rm -f conftest*])
-
-AM_CONDITIONAL(HAVE_ARMV7M, test x"$acnewlib_cv_armv7m_processor" = x"yes")
-
 AC_SUBST(CFLAGS)
 
 AC_CONFIG_FILES([Makefile])
diff --git a/newlib/libc/machine/arm/memcpy-stub.c b/newlib/libc/machine/arm/memcpy-stub.c
new file mode 100644
index 000000000..52a0f91bd
--- /dev/null
+++ b/newlib/libc/machine/arm/memcpy-stub.c
@@ -0,0 +1,41 @@
+/* Copyright (c) 2015 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:
+       * Redistributions of source code must retain the above copyright
+	 notice, this list of conditions and the following disclaimer.
+       * 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.
+       * Neither the name of the Linaro nor the
+	 names of its contributors may be used to endorse or promote products
+	 derived from this software without specific prior written permission.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+   "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 THE COPYRIGHT
+   HOLDER OR CONTRIBUTORS 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.  */
+
+/* The structure of the following #if #else #endif conditional chain
+   must match the chain in memcpy.S.  */
+
+#include "acle-compat.h"
+
+#if (defined (__OPTIMIZE_SIZE__) || defined (PREFER_SIZE_OVER_SPEED))
+# include "../../string/memcpy.c"
+#elif (__ARM_ARCH >= 7 && __ARM_ARCH_PROFILE == 'A' \
+       && defined (__ARM_FEATURE_UNALIGNED))
+/* Defined in memcpy.S.  */
+#elif __ARM_ARCH >= 7 && __ARM_ARCH_PROFILE == 'M'
+/* Defined in memcpy.S.  */
+#else
+# include "../../string/memcpy.c"
+#endif
diff --git a/newlib/libc/machine/arm/memcpy.S b/newlib/libc/machine/arm/memcpy.S
index b1bab88bf..d9d5810a7 100644
--- a/newlib/libc/machine/arm/memcpy.S
+++ b/newlib/libc/machine/arm/memcpy.S
@@ -26,27 +26,22 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#if defined (__OPTIMIZE_SIZE__) || defined (PREFER_SIZE_OVER_SPEED)
-  /* Leave this field blank.  So the memcpy() is not defined, and this will
-     automatically pull in the default C definition of memcpy() from
-     ../../string/memcpy.c.  No need to include this file explicitely.
-     The lib_a-memcpy.o will not be generated, so it won't replace the default
-     lib_a-memcpy.o which is generated by ../../string/memcpy.c.
-     See the commands in configure.in and Makefile.am for more details.
+/* The structure of the following #if #else #endif conditional chain
+   must match the chain in memcpy-stub.c.  */
+
+#include "acle-compat.h"
 
-     However, if we need to rewrite this function to be more efficient, we
-     can add the corresponding assembly code into this field and change the
-     commands in configure.in and Makefile.am to allow the corresponding
-     lib_a-memcpy.o to be generated.
-  */
+#if defined (__OPTIMIZE_SIZE__) || defined (PREFER_SIZE_OVER_SPEED)
+  /* Defined in memcpy-stub.c.  */
 
 #elif (__ARM_ARCH >= 7 && __ARM_ARCH_PROFILE == 'A' \
        && defined (__ARM_FEATURE_UNALIGNED))
 #include "memcpy-armv7a.S"
 
-#elif defined (__ARM_ARCH_7M__) || defined (__ARM_ARCH_7EM__)
+#elif __ARM_ARCH >= 7 && __ARM_ARCH_PROFILE == 'M'
 #include "memcpy-armv7m.S"
 
 #else
-  /* Leave this filed blank.  See the commands above.  */
+  /* Defined in memcpy-stub.c.  */
+
 #endif