[Qemu-devel] [PATCH 2/6] simplify cpu_exec

[Glauber Costa <gcosta@redhat.com>]

This is a first attempt to simplify cpu_exec(): it has simply
too many ifdefs, which is not a very good practice at all.

Following some work I've already posted in the past, I'm moving the target-b
ifdefs to target-xxx/helper.c, encapsuled into relevant functions.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
---
 cpu-exec.c         |   43 ++-----------------------------------------
 exec-all.h         |   10 ++++++++++
 target-i386/exec.h |   15 +++++++++++++++
 target-m68k/exec.h |   16 ++++++++++++++++
 4 files changed, 43 insertions(+), 41 deletions(-)

diff --git a/cpu-exec.c b/cpu-exec.c
index 9b02447..af22e3c 100644
--- a/cpu-exec.c
+++ b/cpu-exec.c
@@ -262,27 +262,8 @@ int cpu_exec(CPUState *env1)
     env = env1;
 
     env_to_regs();
-#if defined(TARGET_I386)
-    /* put eflags in CPU temporary format */
-    CC_SRC = env->eflags & (CC_O | CC_S | CC_Z | CC_A | CC_P | CC_C);
-    DF = 1 - (2 * ((env->eflags >> 10) & 1));
-    CC_OP = CC_OP_EFLAGS;
-    env->eflags &= ~(DF_MASK | CC_O | CC_S | CC_Z | CC_A | CC_P | CC_C);
-#elif defined(TARGET_SPARC)
-#elif defined(TARGET_M68K)
-    env->cc_op = CC_OP_FLAGS;
-    env->cc_dest = env->sr & 0xf;
-    env->cc_x = (env->sr >> 4) & 1;
-#elif defined(TARGET_ALPHA)
-#elif defined(TARGET_ARM)
-#elif defined(TARGET_PPC)
-#elif defined(TARGET_MIPS)
-#elif defined(TARGET_SH4)
-#elif defined(TARGET_CRIS)
+    cpu_load_flags(env);
     /* XXXXX */
-#else
-#error unsupported target CPU
-#endif
     env->exception_index = -1;
 
     /* prepare setjmp context for exception handling */
@@ -631,27 +612,7 @@ int cpu_exec(CPUState *env1)
         }
     } /* for(;;) */
 
-
-#if defined(TARGET_I386)
-    /* restore flags in standard format */
-    env->eflags = env->eflags | cc_table[CC_OP].compute_all() | (DF & DF_MASK);
-#elif defined(TARGET_ARM)
-    /* XXX: Save/restore host fpu exception state?.  */
-#elif defined(TARGET_SPARC)
-#elif defined(TARGET_PPC)
-#elif defined(TARGET_M68K)
-    cpu_m68k_flush_flags(env, env->cc_op);
-    env->cc_op = CC_OP_FLAGS;
-    env->sr = (env->sr & 0xffe0)
-              | env->cc_dest | (env->cc_x << 4);
-#elif defined(TARGET_MIPS)
-#elif defined(TARGET_SH4)
-#elif defined(TARGET_ALPHA)
-#elif defined(TARGET_CRIS)
-    /* XXXXX */
-#else
-#error unsupported target CPU
-#endif
+    cpu_save_flags(env);
 
     /* restore global registers */
 #include "hostregs_helper.h"
diff --git a/exec-all.h b/exec-all.h
index 51b27b5..0eea2f1 100644
--- a/exec-all.h
+++ b/exec-all.h
@@ -82,6 +82,16 @@ int cpu_restore_state_copy(struct TranslationBlock *tb,
                            void *puc);
 void cpu_resume_from_signal(CPUState *env1, void *puc);
 void cpu_exec_init(CPUState *env);
+
+/* load flags for current execution. Architecture can override */
+#ifndef cpu_load_flags
+#define cpu_load_flags(env) do {} while (0)
+#endif
+/* save flags after cpu execution. Architecture can override */
+#ifndef cpu_save_flags
+#define cpu_save_flags(env) do {} while (0)
+#endif
+
 int page_unprotect(target_ulong address, unsigned long pc, void *puc);
 void tb_invalidate_phys_page_range(target_phys_addr_t start, target_phys_addr_t end,
                                    int is_cpu_write_access);
diff --git a/target-i386/exec.h b/target-i386/exec.h
index 5e46c5a..38ee96b 100644
--- a/target-i386/exec.h
+++ b/target-i386/exec.h
@@ -31,6 +31,21 @@
 
 register struct CPUX86State *env asm(AREG0);
 
+#define cpu_load_flags(env)                                             \
+do {                                                                    \
+    /* put eflags in CPU temporary format */                            \
+    CC_SRC = env->eflags & (CC_O | CC_S | CC_Z | CC_A | CC_P | CC_C);   \
+    DF = 1 - (2 * ((env->eflags >> 10) & 1));                           \
+    CC_OP = CC_OP_EFLAGS;                                               \
+    env->eflags &= ~(DF_MASK | CC_O | CC_S | CC_Z | CC_A | CC_P | CC_C);\
+} while (0)
+
+#define cpu_save_flags(env)                                                     \
+do {                                                                            \
+    /* restore flags in standard format */                                      \
+    env->eflags = env->eflags | cc_table[CC_OP].compute_all() | (DF & DF_MASK); \
+} while (0)
+
 extern FILE *logfile;
 extern int loglevel;
 
diff --git a/target-m68k/exec.h b/target-m68k/exec.h
index 1269445..d4f51b3 100644
--- a/target-m68k/exec.h
+++ b/target-m68k/exec.h
@@ -26,6 +26,22 @@ register uint32_t T0 asm(AREG1);
 /* ??? We don't use T1, but common code expects it to exist  */
 #define T1 env->t1
 
+#define cpu_load_flags(env)                 \
+do {                                        \
+    env->cc_op = CC_OP_FLAGS;               \
+    env->cc_dest = env->sr & 0xf;           \
+    env->cc_x = (env->sr >> 4) & 1;         \
+} while (0)
+
+#define cpu_save_flags(env)                         \
+do {                                                \
+    cpu_m68k_flush_flags(env, env->cc_op);          \
+    env->cc_op = CC_OP_FLAGS;                       \
+    env->sr = (env->sr & 0xffe0)                    \
+              | env->cc_dest | (env->cc_x << 4);    \
+} while (0)
+
+
 #include "cpu.h"
 #include "exec-all.h"
 
-- 
1.5.4.5