sim: generate build dependencies on the fly

Lift the code that GDB is using to generate dependencies on the fly and
port it over to the sim.  Now people shouldn't have to manually maintain
these in their Makefile's.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

1 files changed, 55 insertions, 199 deletions

diff --git a/sim/common/Make-common.in b/sim/common/Make-common.in
index 42e3192..c12d155 100644
--- a/sim/common/Make-common.in
+++ b/sim/common/Make-common.in
@@ -35,7 +35,7 @@
 
 ## COMMON_PRE_CONFIG_FRAG
 
-VPATH = @srcdir@
+VPATH = @srcdir@:$(srccom)
 srcdir = @srcdir@
 srccom = $(srcdir)/../common
 srcroot = $(srcdir)/../..
@@ -109,7 +109,17 @@ AR_FLAGS = rc
 RANLIB = @RANLIB@
 MAKEINFO = makeinfo
 
-DEP = $(srcroot)/mkdep
+# Dependency tracking information.
+DEPMODE = @CCDEPMODE@
+DEPDIR = @DEPDIR@
+depcomp = $(SHELL) $(srcroot)/depcomp
+
+# Note that these are overridden by GNU make-specific code below if
+# GNU make is used.  The overrides implement dependency tracking.
+COMPILE.pre = $(CC)
+COMPILE.post = -c -o $@
+COMPILE = $(COMPILE.pre) $(ALL_CFLAGS) $(COMPILE.post)
+POSTCOMPILE = @true
 
 # Each simulator's Makefile.in defines one or more of these variables
 # to override our settings as necessary.  There is no need to define these
@@ -272,22 +282,11 @@ run$(EXEEXT): $(SIM_RUN_OBJS) libsim.a $(LIBDEPS)
 	$(CC) $(ALL_CFLAGS) $(LDFLAGS) -o run$(EXEEXT) \
 	  $(SIM_RUN_OBJS) libsim.a $(EXTRA_LIBS)
 
-run.o: $(srccom)/run.c config.h tconfig.h $(remote_sim_h) $(callback_h)
-	$(CC) -c $(srccom)/run.c $(ALL_CFLAGS)
-
 # FIXME: Ideally, callback.o and friends live in a library outside of
 # both the gdb and simulator source trees (e.g. devo/remote.  Not
 # devo/libremote because this directory would contain more than just
 # a library).
 
-callback.o: $(srccom)/callback.c config.h tconfig.h $(callback_h) targ-vals.h
-	$(CC) -c $(srccom)/callback.c $(ALL_CFLAGS)
-
-syscall.o: $(srccom)/syscall.c config.h tconfig.h $(callback_h) targ-vals.h
-	$(CC) -c $(srccom)/syscall.c $(ALL_CFLAGS)
-
-targ-map.o: targ-map.c targ-vals.h
-
 gentmap: Makefile $(srccom)/gentmap.c targ-vals.def
 	$(CC_FOR_BUILD) $(srccom)/gentmap.c -o gentmap $(BUILD_CFLAGS) $(NL_TARGET)
 
@@ -305,7 +304,6 @@ version.c: Makefile ../../gdb/version.in
 	echo '#include "version.h"' >> version.c-tmp
 	echo 'const char version[] = "'"`sed q ${srcdir}/../../gdb/version.in`"'";' >> version.c-tmp
 	mv version.c-tmp version.c
-version.o: version.c $(version_h)
 
 
 #
@@ -409,128 +407,57 @@ hw_main_headers = \
 	$(hw-ports_h) \
 	$(hw-properties_h) \
 
-# FIXME: If this complicated way of building .o files from ../common is
-# necessary, the reason should be documented here.
+#
+# Dependency tracking.  Most of this is conditional on GNU Make being
+# found by configure; if GNU Make is not found, we fall back to a
+# simpler scheme.
+#
+
+@GMAKE_TRUE@ifeq ($(DEPMODE),depmode=gcc3)
+# Note that we put the dependencies into a .Tpo file, then move them
+# into place if the compile succeeds.  We need this because gcc does
+# not atomically write the dependency output file.
+@GMAKE_TRUE@override COMPILE.post = -c -o $@ -MT $@ -MMD -MP \
+@GMAKE_TRUE@	-MF $(DEPDIR)/$(basename $(@F)).Tpo
+@GMAKE_TRUE@override POSTCOMPILE = @mv $(DEPDIR)/$(basename $(@F)).Tpo \
+@GMAKE_TRUE@	$(DEPDIR)/$(basename $(@F)).Po
+@GMAKE_TRUE@else
+@GMAKE_TRUE@override COMPILE.pre = source='$<' object='$@' libtool=no \
+@GMAKE_TRUE@	DEPDIR=$(DEPDIR) $(DEPMODE) $(depcomp) $(CC)
+# depcomp handles atomicity for us, so we don't need a postcompile
+# step.
+@GMAKE_TRUE@override POSTCOMPILE =
+@GMAKE_TRUE@endif
+
+all_object_files = $(LIB_OBJS) $(SIM_RUN_OBJS)
+generated_files = \
+	$(SIM_EXTRA_DEPS) \
+	hw-config.h \
+	targ-map.c \
+	targ-vals.h \
+	version.c
+
+# Ensure that generated files are created early.  Use order-only
+# dependencies if available.  They require GNU make 3.80 or newer,
+# and the .VARIABLES variable was introduced at the same time.
+@GMAKE_TRUE@ifdef .VARIABLES
+@GMAKE_TRUE@$(all_object_files): | $(generated_files)
+@GMAKE_TRUE@else
+$(all_object_files) : $(generated_files)
+@GMAKE_TRUE@endif
+
+# Dependencies.
+@GMAKE_TRUE@-include $(patsubst %.o, $(DEPDIR)/%.Po, $(all_object_files))
 
 BUILT_SRC_FROM_COMMON= \
 	sim-inline.c
 
-sim-abort.o: $(srccom)/sim-abort.c \
-	  $(SIM_EXTRA_DEPS)
-	$(CC) -c $(srccom)/sim-abort.c $(ALL_CFLAGS)
-
-sim-arange.o: $(srccom)/sim-arange.c $(sim-arange_h) $(SIM_EXTRA_DEPS)
-	$(CC) -c $(srccom)/sim-arange.c $(ALL_CFLAGS)
-
-sim-bits.o: $(srccom)/sim-bits.c $(sim-bits_h) $(sim-n-bits_h) \
-	  $(SIM_EXTRA_DEPS)
-	$(CC) -c $(srccom)/sim-bits.c $(ALL_CFLAGS)
-
-sim-command.o: $(srccom)/sim-command.c $(sim_main_headers)
-	$(CC) -c $(srccom)/sim-command.c $(ALL_CFLAGS)
-
-sim-config.o: $(srccom)/sim-config.c $(sim-config_h) sim-main.h \
-	  $(SIM_EXTRA_DEPS)
-	$(CC) -c $(srccom)/sim-config.c $(ALL_CFLAGS)
-
-sim-core.o: $(srccom)/sim-core.c $(sim_main_headers) \
-	  $(sim-core_h) $(sim-n-core_h)
-	$(CC) -c $(srccom)/sim-core.c $(ALL_CFLAGS)
-
-sim-cpu.o: $(srccom)/sim-cpu.c $(sim_main_headers)
-	$(CC) -c $(srccom)/sim-cpu.c $(ALL_CFLAGS)
-
-sim-endian.o: $(srccom)/sim-endian.c $(sim-endian_h) $(sim-n-endian_h)
-	$(CC) -c $(srccom)/sim-endian.c $(ALL_CFLAGS)
-
-sim-engine.o: $(srccom)/sim-engine.c $(sim_main_headers) $(sim-engine_h)
-	$(CC) -c $(srccom)/sim-engine.c $(ALL_CFLAGS)
-
-sim-events.o: $(srccom)/sim-events.c $(sim-events_h) sim-main.h \
-	  $(SIM_EXTRA_DEPS)
-	$(CC) -c $(srccom)/sim-events.c $(ALL_CFLAGS)
-
-sim-fpu.o: $(srccom)/sim-fpu.c $(sim-fpu_h) \
-	  $(SIM_EXTRA_DEPS)
-	$(CC) -c $(srccom)/sim-fpu.c $(ALL_CFLAGS)
-
-sim-hload.o: $(srccom)/sim-hload.c $(sim-assert_h) $(remote_sim_h) \
-	  $(SIM_EXTRA_DEPS)
-	$(CC) -c $(srccom)/sim-hload.c $(ALL_CFLAGS)
-
-sim-hrw.o: $(srccom)/sim-hrw.c $(sim-assert_h) $(sim_core_h) $(remote_sim_h) \
-	  $(SIM_EXTRA_DEPS)
-	$(CC) -c $(srccom)/sim-hrw.c $(ALL_CFLAGS)
-
-sim-hw.o: $(srccom)/sim-hw.c $(sim_main_headers)
-	$(CC) -c $(srccom)/sim-hw.c $(ALL_CFLAGS)
-
-sim-info.o: $(srccom)/sim-info.c $(sim-assert_h) $(remote_sim_h) \
-	  $(SIM_EXTRA_DEPS)
-	$(CC) -c $(srccom)/sim-info.c $(ALL_CFLAGS)
-
 sim-inline.c: $(srccom)/sim-inline.c
 	rm -f $@ tmp-$@
 	echo "# 1 \"$(srccom)/$@\"" > tmp-$@
 	cat $(srccom)/$@ >> tmp-$@
 	$(SHELL) $(srcdir)/../../move-if-change tmp-$@ $@
 
-sim-io.o: $(srccom)/sim-io.c $(sim_main_headers) $(sim-io_h) $(remote_sim_h) \
-	  targ-vals.h
-	$(CC) -c $(srccom)/sim-io.c $(ALL_CFLAGS)
-
-sim-memopt.o: $(srccom)/sim-memopt.c $(sim_main_headers) \
-	  $(sim-io_h)
-	$(CC) -c $(srccom)/sim-memopt.c $(ALL_CFLAGS)
-
-sim-module.o: $(srccom)/sim-module.c $(sim_main_headers) \
-	  $(sim-io_h)
-	$(CC) -c $(srccom)/sim-module.c $(ALL_CFLAGS)
-
-sim-options.o: $(srccom)/sim-options.c $(sim_main_headers) \
-	  $(sim-options_h) $(sim-io_h)
-	$(CC) -c $(srccom)/sim-options.c $(ALL_CFLAGS)
-
-sim-reason.o: $(srccom)/sim-reason.c $(sim_main_headers) $(remote_sim_h)
-	$(CC) -c $(srccom)/sim-reason.c $(ALL_CFLAGS)
-
-sim-reg.o: $(srccom)/sim-reg.c $(sim_main_headers) $(remote_sim_h)
-	$(CC) -c $(srccom)/sim-reg.c $(ALL_CFLAGS)
-
-sim-resume.o: $(srccom)/sim-resume.c $(sim_main_headers) $(remote_sim_h)
-	$(CC) -c $(srccom)/sim-resume.c $(ALL_CFLAGS)
-
-sim-run.o: $(srccom)/sim-run.c $(sim_main_headers)
-	$(CC) -c $(srccom)/sim-run.c $(ALL_CFLAGS)
-
-sim-signal.o: $(srccom)/sim-signal.c $(sim_main_headers) $(sim-signal_h)
-	$(CC) -c $(srccom)/sim-signal.c $(ALL_CFLAGS)
-
-sim-stop.o: $(srccom)/sim-stop.c $(sim_main_headers)
-	$(CC) -c $(srccom)/sim-stop.c $(ALL_CFLAGS)
-
-sim-trace.o: $(srccom)/sim-trace.c $(sim_main_headers) \
-	  $(sim-options_h) $(sim-io_h)
-	$(CC) -c $(srccom)/sim-trace.c $(ALL_CFLAGS)
-
-sim-profile.o: $(srccom)/sim-profile.c $(sim_main_headers) \
-	  $(sim-options_h) $(sim-io_h)
-	$(CC) -c $(srccom)/sim-profile.c $(ALL_CFLAGS)
-
-sim-model.o: $(srccom)/sim-model.c $(sim_main_headers) \
-	  $(sim-io_h)
-	$(CC) -c $(srccom)/sim-model.c $(ALL_CFLAGS)
-
-sim-utils.o: $(srccom)/sim-utils.c $(sim_main_headers)
-	$(CC) -c $(srccom)/sim-utils.c $(ALL_CFLAGS)
-
-sim-watch.o: $(srccom)/sim-watch.c $(sim_main_headers)
-	$(CC) -c $(srccom)/sim-watch.c $(ALL_CFLAGS)
-
-sim-load.o: $(srccom)/sim-load.c $(callback_h) $(sim-basics_h) $(remote_sim_h)
-	$(CC) -c $(srccom)/sim-load.c $(ALL_CFLAGS)
-
-
 # FIXME This is one very simple-minded way of generating the file hw-config.h
 hw-config.h: Makefile.in $(srccom)/Make-common.in config.status Makefile
 	rm -f tmp-hw.h
@@ -546,59 +473,10 @@ hw-config.h: Makefile.in $(srccom)/Make-common.in config.status Makefile
 	echo "};" >> tmp-hw.h
 	mv tmp-hw.h hw-config.h
 
-hw-alloc.o: $(srccom)/hw-alloc.c $(hw_main_headers)
-	$(CC) -c $(srccom)/hw-alloc.c $(ALL_CFLAGS)
-
-hw-base.o: $(srccom)/hw-base.c $(hw_main_headers) hw-config.h
-	$(CC) -c $(srccom)/hw-base.c $(ALL_CFLAGS)
-
-hw-device.o: $(srccom)/hw-device.c $(hw_main_headers)
-	$(CC) -c $(srccom)/hw-device.c $(ALL_CFLAGS)
-
-hw-events.o: $(srccom)/hw-events.c $(hw_main_headers) $(sim_main_headers)
-	$(CC) -c $(srccom)/hw-events.c $(ALL_CFLAGS)
-
 test-hw-events: $(srccom)/hw-events.c libsim.a
 	$(CC) $(ALL_CFLAGS) -DMAIN -o test-hw-events$(EXEEXT) \
 		$(srccom)/hw-events.c libsim.a $(EXTRA_LIBS)
 
-hw-instances.o: $(srccom)/hw-instances.c $(hw_main_headers)
-	$(CC) -c $(srccom)/hw-instances.c $(ALL_CFLAGS)
-
-hw-handles.o: $(srccom)/hw-handles.c $(hw_main_headers)
-	$(CC) -c $(srccom)/hw-handles.c $(ALL_CFLAGS)
-
-hw-ports.o: $(srccom)/hw-ports.c $(hw_main_headers)
-	$(CC) -c $(srccom)/hw-ports.c $(ALL_CFLAGS)
-
-hw-properties.o: $(srccom)/hw-properties.c $(hw_main_headers)
-	$(CC) -c $(srccom)/hw-properties.c $(ALL_CFLAGS)
-
-hw-tree.o: $(srccom)/hw-tree.c $(hw_main_headers) $(hw-tree_h)
-	$(CC) -c $(srccom)/hw-tree.c $(ALL_CFLAGS)
-
-# Devices.
-
-dv-cfi.o: $(srccom)/dv-cfi.c $(hw_main_headers) $(sim_main_headers)
-	$(CC) -c $(srccom)/dv-cfi.c $(ALL_CFLAGS)
-
-dv-core.o: $(srccom)/dv-core.c $(hw_main_headers) $(sim_main_headers)
-	$(CC) -c $(srccom)/dv-core.c $(ALL_CFLAGS)
-
-dv-glue.o: $(srccom)/dv-glue.c $(hw_main_headers) $(sim_main_headers)
-	$(CC) -c $(srccom)/dv-glue.c $(ALL_CFLAGS)
-
-dv-pal.o: $(srccom)/dv-pal.c $(hw_main_headers) $(sim_main_headers)
-	$(CC) -c $(srccom)/dv-pal.c $(ALL_CFLAGS)
-
-dv-sockser.o: $(srccom)/dv-sockser.h $(sim_main_headers)
-	$(CC) -c $(srccom)/dv-sockser.c $(ALL_CFLAGS)
-
-
-nrun.o: $(srccom)/nrun.c config.h tconfig.h $(remote_sim_h) $(callback_h) \
-	  $(sim_main_headers)
-	$(CC) -c $(srccom)/nrun.c $(ALL_CFLAGS)
-
 # CGEN support.
 
 # For use in Makefile.in for cpu-specific files.
@@ -607,29 +485,6 @@ CGEN_MAIN_CPU_DEPS = \
 	$(srccom)/cgen-ops.h \
 	$(srccom)/cgen-mem.h
 
-cgen-run.o: $(srccom)/cgen-run.c $(sim_main_headers)
-	$(CC) -c $(srccom)/cgen-run.c $(ALL_CFLAGS)
-
-cgen-scache.o: $(srccom)/cgen-scache.c $(sim_main_headers)
-	$(CC) -c $(srccom)/cgen-scache.c $(ALL_CFLAGS)
-
-cgen-trace.o: $(srccom)/cgen-trace.c $(sim_main_headers)
-	$(CC) -c $(srccom)/cgen-trace.c $(ALL_CFLAGS)
-
-cgen-fpu.o: $(srccom)/cgen-fpu.c $(sim_main_headers) $(sim-fpu_h)
-	$(CC) -c $(srccom)/cgen-fpu.c $(ALL_CFLAGS)
-
-cgen-accfp.o: $(srccom)/cgen-accfp.c $(sim_main_headers) $(sim-fpu_h)
-	$(CC) -c $(srccom)/cgen-accfp.c $(ALL_CFLAGS)
-
-cgen-utils.o: $(srccom)/cgen-utils.c $(sim_main_headers) \
-	  $(srccom)/cgen-mem.h $(srccom)/cgen-ops.h $(srccom)/cgen-engine.h
-	$(CC) -c $(srccom)/cgen-utils.c $(ALL_CFLAGS)
-
-cgen-par.o: $(srccom)/cgen-par.c $(sim_main_headers) \
-	  $(srccom)/cgen-mem.h $(srccom)/cgen-par.h
-	$(CC) -c $(srccom)/cgen-par.c $(ALL_CFLAGS)
-
 # Support targets.
 
 install: install-common $(SIM_EXTRA_INSTALL)
@@ -680,7 +535,8 @@ distclean mostlyclean maintainer-clean realclean: clean $(SIM_EXTRA_DISTCLEAN)
 	rm -f targ-vals.def
 
 .c.o:
-	$(CC) -c $(ALL_CFLAGS) $<
+	$(COMPILE) $<
+	$(POSTCOMPILE)
 
 # Dummy target to force execution of dependent targets.
 force: