Prevent unnecessary recompilation for trivial params.def changes

2015-09-08  Tom de Vries  <tom@codesourcery.com>

	* Makefile.in (generated_files): Add params.list.
	(params.list, s-params.list): Add rule.
	* params.h (enum compiler_param): Include params-list.h.  Move define
	DEFPARAM, include params.def and undef DEFPARAM ...
	* params-list.h: ... here.  New file.

From-SVN: r227566

gcc/ChangeLog

+2015-09-08  Tom de Vries  <tom@codesourcery.com>
+
+	* Makefile.in (generated_files): Add params.list.
+	(params.list, s-params.list): Add rule.
+	* params.h (enum compiler_param): Include params-list.h.  Move define
+	DEFPARAM, include params.def and undef DEFPARAM ...
+	* params-list.h: ... here.  New file.
+
 2015-09-08  David Malcolm  <dmalcolm@redhat.com>
 
 	* pretty-print.h (printer_fn): Fix typo in comment.

gcc/Makefile.in

@@ -2415,7 +2415,7 @@ generated_files = config.h tm.h $(TM_P_H) $(TM_H) multilib.h \
        $(ALL_GTFILES_H) gtype-desc.c gtype-desc.h gcov-iov.h \
        options.h target-hooks-def.h insn-opinit.h \
        common/common-target-hooks-def.h pass-instances.def \
-       c-family/c-target-hooks-def.h
+       c-family/c-target-hooks-def.h params.list
 
 #
 # How to compile object files to run on the build machine.
@@ -3236,6 +3236,12 @@ installdirs:
 	$(mkinstalldirs) $(DESTDIR)$(man1dir)
 	$(mkinstalldirs) $(DESTDIR)$(man7dir)
 
+params.list: s-params.list; @true
+s-params.list: $(srcdir)/params-list.h $(srcdir)/params.def
+	$(CPP) $(srcdir)/params-list.h | sed 's/^#.*//;/^$$/d' > tmp-params.list
+	$(SHELL) $(srcdir)/../move-if-change tmp-params.list params.list
+	$(STAMP) s-params.list
+
 PLUGIN_HEADERS = $(TREE_H) $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) \
   toplev.h $(DIAGNOSTIC_CORE_H) $(BASIC_BLOCK_H) $(HASH_TABLE_H) \
   tree-ssa-alias.h $(INTERNAL_FN_H) gimple-fold.h tree-eh.h gimple-expr.h \

gcc/params-list.h

+#define DEFPARAM(enumerator, option, nocmsgid, default, min, max) \
+  enumerator,
+#include "params.def"
+#undef DEFPARAM

gcc/params.h

@@ -81,10 +81,7 @@ extern void set_param_value (const char *name, int value,
 
 enum compiler_param
 {
-#define DEFPARAM(enumerator, option, nocmsgid, default, min, max) \
-  enumerator,
-#include "params.def"
-#undef DEFPARAM
+#include "params.list"
   LAST_PARAM
 };