Add option to disable TB cache, by Herve Poussineau.

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3930 c046a42c-6fe2-441c-8c8c-71466251a162

1 files changed, 61 insertions, 1 deletions

diff --git a/cpu-exec.c b/cpu-exec.c
index 8134c229c5..af5c58f8a7 100644
--- a/cpu-exec.c
+++ b/cpu-exec.c
@@ -20,6 +20,7 @@
 #include "config.h"
 #include "exec.h"
 #include "disas.h"
+#include <string.h>
 
 #if !defined(CONFIG_SOFTMMU)
 #undef EAX
@@ -40,6 +41,9 @@ int tb_invalidated_flag;
 //#define DEBUG_EXEC
 //#define DEBUG_SIGNAL
 
+/* translation settings */
+int translation_settings = 0;
+
 #define SAVE_GLOBALS()
 #define RESTORE_GLOBALS()
 
@@ -120,6 +124,56 @@ void cpu_resume_from_signal(CPUState *env1, void *puc)
     longjmp(env->jmp_env, 1);
 }
 
+CPUTranslationSetting cpu_translation_settings[] = {
+    { CPU_SETTING_NO_CACHE, "no-cache",
+      "Do not use translation blocks cache (very slow!)" },
+    { 0, NULL, NULL },
+};
+
+void cpu_set_translation_settings(int translation_flags)
+{
+    translation_settings = translation_flags;
+}
+
+static int cmp1(const char *s1, int n, const char *s2)
+{
+    if (strlen(s2) != n)
+        return 0;
+    return memcmp(s1, s2, n) == 0;
+}
+
+/* takes a comma separated list of translation settings. Return 0 if error. */
+int cpu_str_to_translation_mask(const char *str)
+{
+    CPUTranslationSetting *setting;
+    int mask;
+    const char *p, *p1;
+
+    p = str;
+    mask = 0;
+    for(;;) {
+        p1 = strchr(p, ',');
+        if (!p1)
+            p1 = p + strlen(p);
+        if(cmp1(p,p1-p,"all")) {
+            for(setting = cpu_translation_settings; setting->mask != 0; setting++) {
+                mask |= setting->mask;
+            }
+        } else {
+            for(setting = cpu_translation_settings; setting->mask != 0; setting++) {
+                if (cmp1(p, p1 - p, setting->name))
+                    goto found;
+            }
+            return 0;
+        }
+    found:
+        mask |= setting->mask;
+        if (*p1 != ',')
+            break;
+        p = p1 + 1;
+    }
+    return mask;
+}
 
 static TranslationBlock *tb_find_slow(target_ulong pc,
                                       target_ulong cs_base,
@@ -141,6 +195,9 @@ static TranslationBlock *tb_find_slow(target_ulong pc,
     phys_pc = get_phys_addr_code(env, pc);
     phys_page1 = phys_pc & TARGET_PAGE_MASK;
     phys_page2 = -1;
+    if (translation_settings & CPU_SETTING_NO_CACHE)
+        goto not_found;
+
     h = tb_phys_hash_func(phys_pc);
     ptb1 = &tb_phys_hash[h];
     for(;;) {
@@ -264,7 +321,10 @@ static inline TranslationBlock *tb_find_fast(void)
 #else
 #error unsupported CPU
 #endif
-    tb = env->tb_jmp_cache[tb_jmp_cache_hash_func(pc)];
+    if (translation_settings & CPU_SETTING_NO_CACHE)
+        tb = NULL;
+    else
+        tb = env->tb_jmp_cache[tb_jmp_cache_hash_func(pc)];
     if (__builtin_expect(!tb || tb->pc != pc || tb->cs_base != cs_base ||
                          tb->flags != flags, 0)) {
         tb = tb_find_slow(pc, cs_base, flags);