Index: gcc/doc/configfiles.texi
===================================================================
--- gcc/doc/configfiles.texi	(revision 177990)
+++ gcc/doc/configfiles.texi	(working copy)
@@ -60,5 +60,17 @@ machine.
 @item
 @file{tm_p.h}, which includes the header @file{@var{machine}-protos.h}
 that contains prototypes for functions in the target @file{.c} file.
-FIXME: why is such a separate header necessary?
+The @file{tm_p.h} is needed because the @file{@var{machine}-protos.h}
+will often times include declarations that include RTL and TREE
+datatypes.  These references must be bracketed with @code{#ifdef
+RTX_CODE} and @code{#ifdef TREE_CODE} respecitively.  These
+declarations can't go in the normal @file{@var{machine}.h} file
+because that file is included before @file{rtl.h} and/or @file{tree.h}
+are included.  The @file{tm_p.h} is included after @file{rtl.h} or
+@file{tree.h} are included.
+@item
+@file{tm-bu-funcs.def}, includes the machine dependent builtin
+functions that use the @code{DEF_BUILTIN_MD} macro to reserve the
+machine dependent builtins in the master builtin enum list after the
+standard enumerations.
 @end itemize
Index: gcc/tree.h
===================================================================
--- gcc/tree.h	(revision 177990)
+++ gcc/tree.h	(working copy)
@@ -3503,7 +3503,7 @@ struct GTY(()) tree_function_decl {
      DECL_FUNCTION_CODE.  Otherwise unused.
      ???  The bitfield needs to be able to hold all target function
 	  codes as well.  */
-  ENUM_BITFIELD(built_in_function) function_code : 11;
+  ENUM_BITFIELD(built_in_function) function_code : 12;
   ENUM_BITFIELD(built_in_class) built_in_class : 2;
 
   unsigned static_ctor_flag : 1;
@@ -3526,7 +3526,7 @@ struct GTY(()) tree_function_decl {
   unsigned looping_const_or_pure_flag : 1;
   unsigned has_debug_args_flag : 1;
 
-  /* 2 bits left */
+  /* 1 bit left */
 };
 
 /* The source language of the translation-unit.  */
Index: gcc/configure
===================================================================
--- gcc/configure	(revision 177990)
+++ gcc/configure	(working copy)
@@ -608,6 +608,7 @@ PPLINC
 PPLLIBS
 GMPINC
 GMPLIBS
+tm_builtin_funcs
 target_cpu_default
 fortran_target_objs
 cxx_target_objs
@@ -17913,7 +17914,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 17916 "configure"
+#line 17917 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -18019,7 +18020,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 18022 "configure"
+#line 18023 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -26796,6 +26797,7 @@ fi
 
 
 
+
 # Echo link setup.
 if test x${build} = x${host} ; then
   if test x${host} = x${target} ; then
Index: gcc/builtins.def
===================================================================
--- gcc/builtins.def	(revision 177990)
+++ gcc/builtins.def	(working copy)
@@ -134,6 +134,13 @@ along with GCC; see the file COPYING3.  
   DEF_BUILTIN (ENUM, NAME, BUILT_IN_NORMAL, 0, 0, false, false, \
 	       false, 0, false, false)
 
+/* Allocate the enum and the name for a machine dependent builtin, but do not
+   actually define it here at all.  */
+#undef DEF_BUILTIN_MD
+#define DEF_BUILTIN_MD(ENUM, NAME) \
+  DEF_BUILTIN (ENUM, NAME, BUILT_IN_MD, 0, 0, false, false, \
+	       false, 0, false, false)
+
 /* Builtin used by the implementation of GNU OpenMP.  None of these are
    actually implemented in the compiler; they're all in libgomp.  */
 #undef DEF_GOMP_BUILTIN
@@ -173,6 +180,10 @@ along with GCC; see the file COPYING3.  
 #undef ATTR_MATHFN_FPROUNDING_STORE
 #define ATTR_MATHFN_FPROUNDING_STORE ATTR_NOTHROW_LEAF_LIST
 
+/* Avoid problems with fields that are zeroed by making sure index 0 is not a
+   legitimate builtin.  */
+DEF_BUILTIN_STUB       (BUILT_IN_NONE, (const char *)0)
+
 /* Category: math builtins.  */
 DEF_LIB_BUILTIN        (BUILT_IN_ACOS, "acos", BT_FN_DOUBLE_DOUBLE, ATTR_MATHFN_FPROUNDING_ERRNO)
 DEF_C99_C90RES_BUILTIN (BUILT_IN_ACOSF, "acosf", BT_FN_FLOAT_FLOAT, ATTR_MATHFN_FPROUNDING_ERRNO)
@@ -789,3 +800,6 @@ DEF_BUILTIN_STUB (BUILT_IN_EH_COPY_VALUE
 
 /* OpenMP builtins.  */
 #include "omp-builtins.def"
+
+/* Target machine builtins.  */
+#include "tm-bu-funcs.def"
Index: gcc/configure.ac
===================================================================
--- gcc/configure.ac	(revision 177990)
+++ gcc/configure.ac	(working copy)
@@ -4923,6 +4923,7 @@ AC_SUBST(c_target_objs)
 AC_SUBST(cxx_target_objs)
 AC_SUBST(fortran_target_objs)
 AC_SUBST(target_cpu_default)
+AC_SUBST(tm_builtin_funcs)
 
 AC_SUBST_FILE(language_hooks)
 
Index: gcc/lto/Make-lang.in
===================================================================
--- gcc/lto/Make-lang.in	(revision 177990)
+++ gcc/lto/Make-lang.in	(working copy)
@@ -79,7 +79,8 @@ $(LTO_EXE): $(LTO_OBJS) $(BACKEND) $(LIB
 lto/lto-lang.o: lto/lto-lang.c $(CONFIG_H) coretypes.h debug.h \
 	flags.h $(GGC_H) langhooks.h $(LANGHOOKS_DEF_H) $(SYSTEM_H) \
 	$(TARGET_H) $(LTO_H) $(GIMPLE_H) gtype-lto.h gt-lto-lto-lang.h \
-	$(EXPR_H) $(LTO_STREAMER_H)
+	$(EXPR_H) $(LTO_STREAMER_H) builtin-attrs.def builtin-types.def \
+	$(BUILTINS_DEF)
 lto/lto.o: lto/lto.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(OPTS_H) \
 	toplev.h $(TREE_H) $(TREE_FLOW_H) $(DIAGNOSTIC_CORE_H) $(TM_H) \
 	$(CGRAPH_H) $(GGC_H) tree-ssa-operands.h $(TREE_PASS_H) \
Index: gcc/config.gcc
===================================================================
--- gcc/config.gcc	(revision 177990)
+++ gcc/config.gcc	(working copy)
@@ -186,7 +186,10 @@
 #  configure_default_options
 #			Set to an initializer for configure_default_options
 #			in configargs.h, based on --with-cpu et cetera.
-
+#
+#  tm_builtin_funcs	Set to additional files in the target directory to
+#			provide target specific builtin functions.
+#
 # The following variables are used in each case-construct to build up the
 # outgoing variables:
 #
@@ -238,6 +241,7 @@ default_gnu_indirect_function=no
 target_gtfiles=
 need_64bit_hwint=
 need_64bit_isa=
+tm_builtin_funcs=
 
 # Don't carry these over build->host->target.  Please.
 xm_file=
Index: gcc/Makefile.in
===================================================================
--- gcc/Makefile.in	(revision 177990)
+++ gcc/Makefile.in	(working copy)
@@ -909,7 +909,9 @@ RTL_H = $(RTL_BASE_H) genrtl.h vecir.h
 RTL_ERROR_H = $(RTL_H) $(DIAGNOSTIC_CORE_H)
 READ_MD_H = $(OBSTACK_H) $(HASHTAB_H) read-md.h
 PARAMS_H = params.h params.def
-BUILTINS_DEF = builtins.def sync-builtins.def omp-builtins.def
+BUILTIN_FUNCS_MD = @tm_builtin_funcs@
+BUILTINS_DEF = builtins.def sync-builtins.def omp-builtins.def \
+  tm-bu-funcs.def $(BUILTIN_FUNCS_MD)
 INTERNAL_FN_DEF = internal-fn.def
 INTERNAL_FN_H = internal-fn.h $(INTERNAL_FN_DEF)
 TREE_H = tree.h all-tree.def tree.def c-family/c-common.def \
@@ -1979,6 +1981,19 @@ $(T)crtbeginT.o: crtstuff.c $(GCC_PASSES
 	$(GCC_FOR_TARGET) $(CRTSTUFF_CFLAGS) $(CRTSTUFF_T_CFLAGS) \
 	  -c $(srcdir)/crtstuff.c -DCRT_BEGIN -DCRTSTUFFT_O \
 	  -o $(T)crtbeginT$(objext)
+
+# Build the builtin include files that includes the standard builtin file along
+# with any machine dependent versions of those files.  Note, this files is
+# expected to be included multiple times, so don't use mkconfig.sh which adds
+# header guards
+tm-bu-funcs.def: s-bu-funcs; @true
+s-bu-funcs: Makefile
+	for inc in $(BUILTIN_FUNCS_MD); do \
+	  echo "#include \"$$inc\""; \
+	done > tmp-bu-funcs.def
+	$(SHELL) $(srcdir)/../move-if-change tmp-bu-funcs.def tm-bu-funcs.def
+	$(STAMP) s-bu-funcs
+
 #
 # Compiling object files from source files.
 
@@ -4511,6 +4526,8 @@ mostlyclean: lang.mostlyclean
 	-rm -f gtype.state
 # Delete genchecksum outputs
 	-rm -f *-checksum.c
+# Delete builtin types, attributes, function include files
+	-rm -f tm-bu-funcs.def
 
 # Delete all files made by compilation
 # that don't exist in the distribution.