[PATCH 1/7] newlib: libm: merge machine/ trampoline up a level

The machine/{configure,Makefile} files exist only to fan out to the
specific machine/$arch/ subdir.  We already have all that same info
in the libm/ dir itself, so by moving the recursive configure and
make calls into it, we can cut off this logic entirely and save the
overhead.

For arches that don't have a machine subdir, it means they can skip
the logic entirely.
---
 newlib/libm/Makefile.am          |     5 +-
 newlib/libm/Makefile.in          |     6 +-
 newlib/libm/common/Makefile.in   |     1 +
 newlib/libm/complex/Makefile.in  |     1 +
 newlib/libm/configure            |    71 +-
 newlib/libm/configure.ac         |    25 +-
 newlib/libm/fenv/Makefile.in     |     1 +
 newlib/libm/machine/Makefile.am  |    26 -
 newlib/libm/machine/Makefile.in  |   650 --
 newlib/libm/machine/aclocal.m4   |  1178 ---
 newlib/libm/machine/configure    | 14383 -----------------------------
 newlib/libm/machine/configure.ac |    53 -
 newlib/libm/math/Makefile.in     |     1 +
 newlib/libm/mathfp/Makefile.in   |     1 +
 14 files changed, 93 insertions(+), 16309 deletions(-)
 delete mode 100644 newlib/libm/machine/Makefile.am
 delete mode 100644 newlib/libm/machine/Makefile.in
 delete mode 100644 newlib/libm/machine/aclocal.m4
 delete mode 100755 newlib/libm/machine/configure
 delete mode 100644 newlib/libm/machine/configure.ac

diff --git a/newlib/libm/Makefile.am b/newlib/libm/Makefile.am
index 8d355cbf6f69..5165ff34b9c0 100644
--- a/newlib/libm/Makefile.am
+++ b/newlib/libm/Makefile.am
@@ -6,7 +6,10 @@ else
 MATHDIR = math
 endif
 
-SUBDIRS = $(MATHDIR) common complex fenv machine
+SUBDIRS = $(MATHDIR) common complex fenv
+if HAVE_LIBM_MACHINE_DIR
+SUBDIRS += $(LIBM_MACHINE_DIR)
+endif
 
 libm_la_LDFLAGS = -Xcompiler -nostdlib
 
diff --git a/newlib/libm/configure.ac b/newlib/libm/configure.ac
index 3f9c01e1563f..44d3391bd60c 100644
--- a/newlib/libm/configure.ac
+++ b/newlib/libm/configure.ac
@@ -27,20 +27,35 @@ if test "${use_libtool}" = "yes"; then
 LT_INIT([win32-dll])
 fi
 
-AC_CONFIG_SUBDIRS(machine)
-
 AC_TYPE_LONG_DOUBLE
 AM_CONDITIONAL(HAVE_LONG_DOUBLE, test x"$ac_cv_type_long_double" = x"yes")
 
 LIBM_MACHINE_LIB=
 if test -n "${libm_machine_dir}"; then
+  case ${libm_machine_dir} in
+    aarch64) AC_CONFIG_SUBDIRS(machine/aarch64) ;;
+    arm) AC_CONFIG_SUBDIRS(machine/arm) ;;
+    i386) AC_CONFIG_SUBDIRS(machine/i386) ;;
+    nds32) AC_CONFIG_SUBDIRS(machine/nds32) ;;
+    pru) AC_CONFIG_SUBDIRS(machine/pru) ;;
+    spu) AC_CONFIG_SUBDIRS(machine/spu) ;;
+    riscv) AC_CONFIG_SUBDIRS(machine/riscv) ;;
+    x86_64) AC_CONFIG_SUBDIRS(machine/x86_64) ;;
+    powerpc) AC_CONFIG_SUBDIRS(machine/powerpc) ;;
+    sparc) AC_CONFIG_SUBDIRS(machine/sparc) ;;
+    mips) AC_CONFIG_SUBDIRS(machine/mips) ;;
+    *) AC_MSG_ERROR([unsupported libm_machine_dir "${libm_machine_dir}"]) ;;
+  esac
+
+  LIBM_MACHINE_DIR=machine/${libm_machine_dir}
   if test "${use_libtool}" = "yes"; then
-    LIBM_MACHINE_LIB=machine/${libm_machine_dir}/lib${libm_machine_dir}.${aext}
+    LIBM_MACHINE_LIB=${LIBM_MACHINE_DIR}/lib${libm_machine_dir}.${aext}
   else
-    LIBM_MACHINE_LIB=machine/lib.${aext}
+    LIBM_MACHINE_LIB=${LIBM_MACHINE_DIR}/lib.${aext}
   fi
 fi
-
+AM_CONDITIONAL(HAVE_LIBM_MACHINE_DIR, test "x${LIBM_MACHINE_DIR}" != x)
+AC_SUBST(LIBM_MACHINE_DIR)
 AC_SUBST(LIBM_MACHINE_LIB)
 
 AC_CONFIG_FILES([Makefile math/Makefile mathfp/Makefile common/Makefile complex/Makefile fenv/Makefile])
-- 
2.34.1