Include less of the generated modular QAPI headers

In my "build everything" tree, a change to the types in
qapi-schema.json triggers a recompile of about 4800 out of 5100
objects.

The previous commit split up qmp-commands.h, qmp-event.h, qmp-visit.h,
qapi-types.h. Each of these headers still includes all its shards.
Reduce compile time by including just the shards we actually need.

To illustrate the benefits: adding a type to qapi/migration.json now
recompiles some 2300 instead of 4800 objects. The next commit will
improve it further.

Backports commit 9af2398977a78d37bf184d6ff6bd04c72bfbf006 from qemu

.gitignore

@@ -30,6 +30,8 @@ qemu/x86_64-softmmu/
 
 qemu/qapi-builtin-types.[ch]
 qemu/qapi-builtin-visit.[ch]
+qemu/qapi/qapi-types-common.[ch]
+qemu/qapi/qapi-visit-common.[ch]
 qemu/qapi-types.[ch]
 qemu/qapi-visit.[ch]
 qemu/qapi-gen-timestamp

qemu/hw/i386/pc.c

@@ -31,7 +31,8 @@
 #include "sysemu/sysemu.h"
 #include "target/i386/topology.h"
 #include "qapi/error.h"
-#include "qapi-visit.h"
+#include "qapi/qapi-visit-common.h"
+#include "qapi/visitor.h"
 
 
 /* XXX: add IGNNE support */

qemu/include/qapi/qmp/qobject.h

@@ -32,9 +32,7 @@
 #ifndef QOBJECT_H
 #define QOBJECT_H
 
-#include <stddef.h>
-#include <assert.h>
-#include "qapi-types.h"
+#include "qapi-builtin-types.h"
 
 struct QObject {
     QType type;

qemu/include/qapi/visitor.h

@@ -14,10 +14,7 @@
 #ifndef QAPI_VISITOR_H
 #define QAPI_VISITOR_H
 
-#include "qemu/typedefs.h"
-#include "qapi-types.h"
-#include "qapi/error.h"
-#include <stdlib.h>
+#include "qapi-builtin-types.h"
 
 /*
  * The QAPI schema defines both a set of C data types, and a QMP wire

qemu/include/qom/object.h

@@ -16,7 +16,7 @@
 
 #include "glib_compat.h"
 #include "unicorn/platform.h"
-#include "qapi-types.h"
+#include "qapi-builtin-types.h"
 #include "qemu/queue.h"
 #include "qemu/typedefs.h"
 #include "qapi/error.h"

qemu/qom/object.c

@@ -15,8 +15,8 @@
 #include "qom/object.h"
 #include "qemu/cutils.h"
 #include "qapi/visitor.h"
-#include "qapi-visit.h"
 #include "qapi/string-input-visitor.h"
+#include "qapi-builtin-visit.h"
 #include "qapi/qmp/qerror.h"
 
 /* TODO: replace QObject with a simpler visitor to avoid a dependency

qemu/scripts/qapi/events.py

@@ -165,23 +165,26 @@ class QAPISchemaGenEventVisitor(QAPISchemaModularCVisitor):
         return basename
 
     def _begin_module(self, name):
+        types = self._module_basename('qapi-types', name)
+        visit = self._module_basename('qapi-visit', name)
         self._genc.add(mcgen('''
 #include "qemu-common.h"
 #include "%(prefix)sqapi-event.h"
-#include "%(prefix)sqapi-visit.h"
+#include "%(visit)s.h"
 #include "qapi/error.h"
 #include "qapi/qmp/qdict.h"
 #include "qapi/qobject-output-visitor.h"
 #include "qapi/qmp-event.h"
 
 ''',
-                             prefix=self._prefix))
+                             visit=visit, prefix=self._prefix))
 
         self._genh.add(mcgen('''
-#include "%(prefix)sqapi-types.h"
+/* #include "qapi/util.h" */
+#include "%(types)s.h"
 
 ''',
-                             prefix=self._prefix))
+                             types=types))
 
     def visit_end(self):
         self._genh.add(gen_enum(self._enum_name, self._event_names))

qemu/scripts/qapi/types.py

@@ -185,13 +185,15 @@ class QAPISchemaGenTypeVisitor(QAPISchemaModularCVisitor):
 '''))
 
     def _begin_module(self, name):
+        types = self._module_basename('qapi-types', name)
+        visit = self._module_basename('qapi-visit', name)
         self._genc.preamble_add(mcgen('''
 #include "qemu/osdep.h"
 #include "qapi/dealloc-visitor.h"
-#include "%(prefix)sqapi-types.h"
-#include "%(prefix)sqapi-visit.h"
+#include "%(types)s.h"
+#include "%(visit)s.h"
 ''',
-                                      prefix=self._prefix))
+                                      types=types, visit=visit))
         self._genh.preamble_add(mcgen('''
 #include "qapi-builtin-types.h"
 '''))

qemu/scripts/qapi/visit.py

@@ -284,20 +284,22 @@ class QAPISchemaGenVisitVisitor(QAPISchemaModularCVisitor):
                                       prefix=prefix))
 
     def _begin_module(self, name):
+        types = self._module_basename('qapi-types', name)
+        visit = self._module_basename('qapi-visit', name)
         self._genc.preamble_add(mcgen('''
 #include "qemu/osdep.h"
 #include "qemu-common.h"
 #include "qapi/error.h"
 #include "qapi/qmp/qerror.h"
-#include "%(prefix)sqapi-visit.h"
+#include "%(visit)s.h"
 ''',
-                                      prefix=self._prefix))
+                                      visit=visit, prefix=self._prefix))
         self._genh.preamble_add(mcgen('''
 #include "qapi-builtin-visit.h"
-#include "%(prefix)sqapi-types.h"
+#include "%(types)s.h"
 
 ''',
-                                      prefix=self._prefix))
+                                      types=types))
 
     def visit_enum_type(self, name, info, values, prefix):
         self._genh.add(gen_visit_decl(name, scalar=True))