x86/mm: avoid building multiple .o from a single .c file

This replace the use of a single .c file use for multiple .o file by
creating multiple .c file including the first one.

There's quite a few issues with trying to build more than one object
file from a single source file: there's is a duplication of the make
rules to generate those targets; there is an additional ".file" symbol
added in order to differentiate between the object files; and the
tools/symbols have an heuristic to try to pick up the right ".file".

This patch adds new .c source file which avoid the need to add a
second ".file" symbol and thus avoid the need to deal with those
issues.

Also remove __OBJECT_FILE__ from $(CC) command line as it isn't used
anywhere anymore. And remove the macro "build-intermediate" since the
generic rules for single targets can be used.

And rename the objects in mm/hap/ to remove the extra "level".

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>

xen/Makefile

@@ -518,17 +518,6 @@ _MAP:
 %/: FORCE
 	$(MAKE) -f $(BASEDIR)/Rules.mk -C $* built_in.o built_in_bin.o
 
-build-intermediate = $(eval $(call build-intermediate-closure,$(1)))
-define build-intermediate-closure
-$(1): FORCE
-	$(MAKE) -f $(BASEDIR)/Rules.mk -C $$(@D) $$(@F)
-endef
-
-$(foreach base,arch/x86/mm/guest_walk_% \
-               arch/x86/mm/hap/guest_walk_%level \
-               arch/x86/mm/shadow/guest_%, \
-    $(foreach ext,o i s,$(call build-intermediate,$(base).$(ext))))
-
 .PHONY: cloc
 cloc:
 	$(eval tmpfile := $(shell mktemp))

xen/Rules.mk

@@ -122,7 +122,7 @@ cpp_flags = $(filter-out -Wa$(comma)% -flto,$(1))
 # Calculation of flags, first the generic flags, then the arch specific flags,
 # and last the flags modified for a target or a directory.
 
-c_flags = -MMD -MP -MF $(@D)/.$(@F).d $(XEN_CFLAGS) '-D__OBJECT_FILE__="$@"'
+c_flags = -MMD -MP -MF $(@D)/.$(@F).d $(XEN_CFLAGS)
 a_flags = -MMD -MP -MF $(@D)/.$(@F).d $(XEN_AFLAGS)
 
 include $(BASEDIR)/arch/$(TARGET_ARCH)/Rules.mk

xen/arch/x86/mm/Makefile

@@ -10,12 +10,3 @@ obj-$(CONFIG_MEM_SHARING) += mem_sharing.o
 obj-y += p2m.o
 obj-$(CONFIG_HVM) += p2m-ept.o p2m-pod.o p2m-pt.o
 obj-y += paging.o
-
-guest_walk_%.o: guest_walk.c Makefile
-	$(CC) $(c_flags) -DGUEST_PAGING_LEVELS=$* -c $< -o $@
-
-guest_walk_%.i: guest_walk.c Makefile
-	$(CPP) $(call cpp_flags,$(c_flags)) -DGUEST_PAGING_LEVELS=$* -c $< -o $@
-
-guest_walk_%.s: guest_walk.c Makefile
-	$(CC) $(filter-out -Wa$(comma)%,$(c_flags)) -DGUEST_PAGING_LEVELS=$* -S $< -o $@

xen/arch/x86/mm/guest_walk.c

@@ -21,9 +21,6 @@
  * along with this program; If not, see <http://www.gnu.org/licenses/>.
  */
 
-/* Allow uniquely identifying static symbols in the 3 generated objects. */
-asm(".file \"" __OBJECT_FILE__ "\"");
-
 #include <xen/types.h>
 #include <xen/mm.h>
 #include <xen/paging.h>

xen/arch/x86/mm/guest_walk_2.c

@@ -0,0 +1,2 @@
+#define GUEST_PAGING_LEVELS 2
+#include "guest_walk.c"

xen/arch/x86/mm/guest_walk_3.c

@@ -0,0 +1,2 @@
+#define GUEST_PAGING_LEVELS 3
+#include "guest_walk.c"

xen/arch/x86/mm/guest_walk_4.c

@@ -0,0 +1,2 @@
+#define GUEST_PAGING_LEVELS 4
+#include "guest_walk.c"

xen/arch/x86/mm/hap/Makefile

@@ -1,15 +1,6 @@
 obj-y += hap.o
-obj-y += guest_walk_2level.o
-obj-y += guest_walk_3level.o
-obj-y += guest_walk_4level.o
+obj-y += guest_walk_2.o
+obj-y += guest_walk_3.o
+obj-y += guest_walk_4.o
 obj-y += nested_hap.o
 obj-y += nested_ept.o
-
-guest_walk_%level.o: guest_walk.c Makefile
-	$(CC) $(c_flags) -DGUEST_PAGING_LEVELS=$* -c $< -o $@
-
-guest_walk_%level.i: guest_walk.c Makefile
-	$(CPP) $(call cpp_flags,$(c_flags)) -DGUEST_PAGING_LEVELS=$* -c $< -o $@
-
-guest_walk_%level.s: guest_walk.c Makefile
-	$(CC) $(filter-out -Wa$(comma)%,$(c_flags)) -DGUEST_PAGING_LEVELS=$* -S $< -o $@

xen/arch/x86/mm/hap/guest_walk.c

@@ -18,9 +18,6 @@
  * this program; If not, see <http://www.gnu.org/licenses/>.
  */
 
-/* Allow uniquely identifying static symbols in the 3 generated objects. */
-asm(".file \"" __OBJECT_FILE__ "\"");
-
 #include <xen/domain_page.h>
 #include <xen/paging.h>
 #include <xen/sched.h>

xen/arch/x86/mm/hap/guest_walk_2.c

@@ -0,0 +1,2 @@
+#define GUEST_PAGING_LEVELS 2
+#include "guest_walk.c"

xen/arch/x86/mm/hap/guest_walk_3.c

@@ -0,0 +1,2 @@
+#define GUEST_PAGING_LEVELS 3
+#include "guest_walk.c"

xen/arch/x86/mm/hap/guest_walk_4.c

@@ -0,0 +1,2 @@
+#define GUEST_PAGING_LEVELS 4
+#include "guest_walk.c"

xen/arch/x86/mm/shadow/Makefile

@@ -5,12 +5,3 @@ obj-$(CONFIG_PV) += pv.o guest_4.o
 else
 obj-y += none.o
 endif
-
-guest_%.o: multi.c Makefile
-	$(CC) $(c_flags) -DGUEST_PAGING_LEVELS=$* -c $< -o $@
-
-guest_%.i: multi.c Makefile
-	$(CPP) $(call cpp_flags,$(c_flags)) -DGUEST_PAGING_LEVELS=$* -c $< -o $@
-
-guest_%.s: multi.c Makefile
-	$(CC) $(filter-out -Wa$(comma)%,$(c_flags)) -DGUEST_PAGING_LEVELS=$* -S $< -o $@

xen/arch/x86/mm/shadow/guest_2.c

@@ -0,0 +1,2 @@
+#define GUEST_PAGING_LEVELS 2
+#include "multi.c"

xen/arch/x86/mm/shadow/guest_3.c

@@ -0,0 +1,2 @@
+#define GUEST_PAGING_LEVELS 3
+#include "multi.c"

xen/arch/x86/mm/shadow/guest_4.c

@@ -0,0 +1,2 @@
+#define GUEST_PAGING_LEVELS 4
+#include "multi.c"

xen/arch/x86/mm/shadow/multi.c

@@ -20,9 +20,6 @@
  * along with this program; If not, see <http://www.gnu.org/licenses/>.
  */
 
-/* Allow uniquely identifying static symbols in the 3 generated objects. */
-asm(".file \"" __OBJECT_FILE__ "\"");
-
 #include <xen/types.h>
 #include <xen/mm.h>
 #include <xen/trace.h>

xen/tools/symbols.c

@@ -84,7 +84,6 @@ static int read_symbol(FILE *in, struct sym_entry *s)
 {
 	char str[500], type[20] = "";
 	char *sym, stype;
-	static enum { symbol, single_source, multi_source } last;
 	static char *filename;
 	int rc = -1;
 
@@ -118,24 +117,11 @@ static int read_symbol(FILE *in, struct sym_entry *s)
 	      */
 	     input_format == fmt_sysv && !*type && stype == '?' && sym &&
 	     sym[1] && strchr("cSsoh", sym[1]) && !sym[2])) {
-		/*
-		 * gas prior to binutils commit fbdf9406b0 (expected to appear
-		 * in 2.27) outputs symbol table entries resulting from .file
-		 * in reverse order. If we get two consecutive file symbols,
-		 * prefer the first one if that names an object file or has a
-		 * directory component (to cover multiply compiled files).
-		 */
-		bool multi = strchr(str, '/') || (sym && sym[1] == 'o');
-
-		if (multi || last != multi_source) {
-			free(filename);
-			filename = *str ? strdup(str) : NULL;
-		}
-		last = multi ? multi_source : single_source;
+		free(filename);
+		filename = *str ? strdup(str) : NULL;
 		goto skip_tail;
 	}
 
-	last = symbol;
 	rc = -1;
 
 	sym = str;