[Qemu-devel] [RFC PATCH 03/10] vl: implement tcg_enabled() and tcg_available() as for other accelerators

[Paolo Bonzini <pbonzini@redhat.com>]

From: Anthony Liguori <aliguori@us.ibm.com>

This way, tcg_enabled() can be used to stub out entire sections of code
that are not used on TCG.  This will limit the use of #ifdef and improves
code checking from the compiler.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch_init.c   | 4 ++++
 exec.c        | 6 +-----
 qemu-common.h | 8 +++++++-
 vl.c          | 2 +-
 4 file modificati, 13 inserzioni(+), 7 rimozioni(-)

diff --git a/arch_init.c b/arch_init.c
index 5a1173e..fb41467 100644
--- a/arch_init.c
+++ b/arch_init.c
@@ -1061,7 +1061,11 @@ int audio_available(void)
 
 int tcg_available(void)
 {
+#if defined(CONFIG_TCG)
     return 1;
+#else
+    return 0;
+#endif
 }
 
 int kvm_available(void)
diff --git a/exec.c b/exec.c
index 5834766..1270d78 100644
--- a/exec.c
+++ b/exec.c
@@ -615,6 +615,7 @@ static void code_gen_alloc(unsigned long tb_size)
    size. */
 void tcg_exec_init(unsigned long tb_size)
 {
+    tcg_allowed = 1;
     cpu_gen_init();
     code_gen_alloc(tb_size);
     code_gen_ptr = code_gen_buffer;
@@ -627,11 +628,6 @@ void tcg_exec_init(unsigned long tb_size)
 #endif
 }
 
-bool tcg_enabled(void)
-{
-    return code_gen_buffer != NULL;
-}
-
 void cpu_exec_init_all(void)
 {
 #if !defined(CONFIG_USER_ONLY)
diff --git a/qemu-common.h b/qemu-common.h
index e5c2bcd..6a3b075 100644
--- a/qemu-common.h
+++ b/qemu-common.h
@@ -301,8 +301,14 @@ typedef struct PCIHostDeviceAddress {
     unsigned int function;
 } PCIHostDeviceAddress;
 
+extern int tcg_allowed;
 void tcg_exec_init(unsigned long tb_size);
-bool tcg_enabled(void);
+
+#ifdef CONFIG_TCG
+#define tcg_enabled()	(tcg_allowed)
+#else
+#define tcg_enabled()	0
+#endif
 
 void cpu_exec_init_all(void);
 
diff --git a/vl.c b/vl.c
index 7c577fa..fa022d1 100644
--- a/vl.c
+++ b/vl.c
@@ -260,7 +260,7 @@ static NotifierList exit_notifiers =
 static NotifierList machine_init_done_notifiers =
     NOTIFIER_LIST_INITIALIZER(machine_init_done_notifiers);
 
-static int tcg_allowed = 1;
+int tcg_allowed = 0;
 int kvm_allowed = 0;
 int xen_allowed = 0;
 uint32_t xen_domid;
-- 
1.7.12