[PATCH 01/34] rs6000: Incorporate new builtins code into the build machinery

[Bill Schmidt <wschmidt@linux.ibm.com>]

Differences from previous version:
 - Removed the change to add rs6000-c.o to extra_objs (unnecessary)
 - Avoided race condition and documented how this works

2021-07-27  Bill Schmidt  <wschmidt@linux.ibm.com>

gcc/
	* config.gcc (powerpc*-*-*): Add rs6000-builtins.o to extra_objs.
	* config/rs6000/rs6000-gen-builtins.c (main): Close init_file
	last.
	* config/rs6000/t-rs6000 (rs6000-gen-builtins.o): New target.
	(rbtree.o): Likewise.
	(rs6000-gen-builtins): Likewise.
	(rs6000-builtins.c): Likewise.
	(rs6000-builtins.h): Likewise.
	(rs6000.o): Add dependency.
	(EXTRA_HEADERS): Add rs6000-vecdefines.h.
	(rs6000-vecdefines.h): New target.
	(rs6000-builtins.o): Likewise.
	(rs6000-call.o): Add rs6000-builtins.h as a dependency.
	(rs6000-c.o): Likewise.
---
 gcc/config.gcc                          |  1 +
 gcc/config/rs6000/rs6000-gen-builtins.c |  4 ++-
 gcc/config/rs6000/t-rs6000              | 46 ++++++++++++++++++++++---
 3 files changed, 45 insertions(+), 6 deletions(-)

diff --git a/gcc/config.gcc b/gcc/config.gcc
index 93e2b3219b9..fe2205b4bc2 100644
--- a/gcc/config.gcc
+++ b/gcc/config.gcc
@@ -476,6 +476,7 @@ powerpc*-*-*)
 	cpu_type=rs6000
 	extra_objs="rs6000-string.o rs6000-p8swap.o rs6000-logue.o"
 	extra_objs="${extra_objs} rs6000-call.o rs6000-pcrel-opt.o"
+	extra_objs="${extra_objs} rs6000-builtins.o"
 	extra_headers="ppc-asm.h altivec.h htmintrin.h htmxlintrin.h"
 	extra_headers="${extra_headers} bmi2intrin.h bmiintrin.h"
 	extra_headers="${extra_headers} xmmintrin.h mm_malloc.h emmintrin.h"
diff --git a/gcc/config/rs6000/rs6000-gen-builtins.c b/gcc/config/rs6000/rs6000-gen-builtins.c
index e5d3b71b622..c401a44e104 100644
--- a/gcc/config/rs6000/rs6000-gen-builtins.c
+++ b/gcc/config/rs6000/rs6000-gen-builtins.c
@@ -2979,9 +2979,11 @@ main (int argc, const char **argv)
       exit (1);
     }
 
+  /* Always close init_file last.  This avoids race conditions in the
+     build machinery.  See comments in t-rs6000.  */
   fclose (header_file);
-  fclose (init_file);
   fclose (defines_file);
+  fclose (init_file);
 
   return 0;
 }
diff --git a/gcc/config/rs6000/t-rs6000 b/gcc/config/rs6000/t-rs6000
index 44f7ffb35fe..e0e8ab8d828 100644
--- a/gcc/config/rs6000/t-rs6000
+++ b/gcc/config/rs6000/t-rs6000
@@ -27,10 +27,6 @@ rs6000-pcrel-opt.o: $(srcdir)/config/rs6000/rs6000-pcrel-opt.c
 	$(COMPILE) $<
 	$(POSTCOMPILE)
 
-rs6000-c.o: $(srcdir)/config/rs6000/rs6000-c.c
-	$(COMPILE) $<
-	$(POSTCOMPILE)
-
 rs6000-string.o: $(srcdir)/config/rs6000/rs6000-string.c
 	$(COMPILE) $<
 	$(POSTCOMPILE)
@@ -47,7 +43,47 @@ rs6000-logue.o: $(srcdir)/config/rs6000/rs6000-logue.c
 	$(COMPILE) $<
 	$(POSTCOMPILE)
 
-rs6000-call.o: $(srcdir)/config/rs6000/rs6000-call.c
+rs6000-gen-builtins.o: $(srcdir)/config/rs6000/rs6000-gen-builtins.c
+	$(COMPILE) $<
+	$(POSTCOMPILE)
+
+rbtree.o: $(srcdir)/config/rs6000/rbtree.c
+	$(COMPILE) $<
+	$(POSTCOMPILE)
+
+rs6000-gen-builtins: rs6000-gen-builtins.o rbtree.o
+	$(LINKER_FOR_BUILD) $(BUILD_LINKERFLAGS) $(BUILD_LDFLAGS) -o $@ \
+	    $(filter-out $(BUILD_LIBDEPS), $^) $(BUILD_LIBS)
+
+# TODO: Whenever GNU make 4.3 is the minimum required, we should use
+# grouped targets on this:
+#    rs6000-builtins.c rs6000-builtins.h rs6000-vecdefines.h &: <deps>
+#       <recipe>
+# For now, the header files depend on rs6000-builtins.c, which avoids
+# races because the .c file is closed last in rs6000-gen-builtins.c.
+rs6000-builtins.c: rs6000-gen-builtins \
+		   $(srcdir)/config/rs6000/rs6000-builtin-new.def \
+		   $(srcdir)/config/rs6000/rs6000-overload.def
+	./rs6000-gen-builtins $(srcdir)/config/rs6000/rs6000-builtin-new.def \
+		$(srcdir)/config/rs6000/rs6000-overload.def rs6000-builtins.h \
+		rs6000-builtins.c rs6000-vecdefines.h
+
+rs6000-builtins.h: rs6000-builtins.c
+
+rs6000.o: rs6000-builtins.h
+
+EXTRA_HEADERS += rs6000-vecdefines.h
+rs6000-vecdefines.h: rs6000-builtins.c
+
+rs6000-builtins.o: rs6000-builtins.c
+	$(COMPILE) $<
+	$(POSTCOMPILE)
+
+rs6000-call.o: $(srcdir)/config/rs6000/rs6000-call.c rs6000-builtins.h
+	$(COMPILE) $<
+	$(POSTCOMPILE)
+
+rs6000-c.o: $(srcdir)/config/rs6000/rs6000-c.c rs6000-builtins.h
 	$(COMPILE) $<
 	$(POSTCOMPILE)
 
-- 
2.27.0