[aot] Add support for running without a GOT for JITted code.

diff --git a/mono/mini/aot-runtime.c b/mono/mini/aot-runtime.c
index 75f332eb9e45a54d314d4c95975b704f249572a2..53195ab095584728f6012324d3fe0c15514c0422 100644 (file)
--- a/mono/mini/aot-runtime.c
+++ b/mono/mini/aot-runtime.c
@@ -68,6 +68,9 @@
 #define ENABLE_AOT_CACHE
 #endif
 
+/* Number of got entries shared between the JIT and LLVM GOT */
+#define N_COMMON_GOT_ENTRIES 4
+
 #define ALIGN_TO(val,align) ((((guint64)val) + ((align) - 1)) & ~((align) - 1))
 #define ALIGN_PTR_TO(ptr,align) (gpointer)((((gssize)(ptr)) + (align - 1)) & (~(align - 1)))
 #define ROUND_DOWN(VALUE,SIZE) ((VALUE) & ~((SIZE) - 1))
@@ -82,6 +85,7 @@ typedef struct MonoAotModule {
        /* Pointer to the Global Offset Table */
        gpointer *got;
        gpointer *llvm_got;
+       gpointer shared_got [N_COMMON_GOT_ENTRIES];
        GHashTable *name_cache;
        GHashTable *extra_methods;
        /* Maps methods to their code */
@@ -200,6 +204,8 @@ static GHashTable *aot_jit_icall_hash;
 #define mono_aot_page_unlock() mono_mutex_unlock (&aot_page_mutex)
 static mono_mutex_t aot_page_mutex;
 
+static MonoAotModule *mscorlib_aot_module;
+
 static void
 init_plt (MonoAotModule *info);
 
@@ -207,7 +213,7 @@ static void
 compute_llvm_code_range (MonoAotModule *amodule, guint8 **code_start, guint8 **code_end);
 
 static gboolean
-mono_aot_init_method (MonoAotModule *amodule, guint32 method_index, MonoMethod *method, MonoClass **klass);
+init_method (MonoAotModule *amodule, guint32 method_index, MonoMethod *method, MonoClass **klass);
 
 /*****************************************************/
 /*                 AOT RUNTIME                       */
@@ -1745,6 +1751,21 @@ get_call_table_entry (void *table, int index)
 #endif
 }
 
+static void
+init_gots (MonoAotModule *amodule)
+{
+       int i;
+
+       if (amodule->got) {
+               for (i = 0; i < N_COMMON_GOT_ENTRIES; ++i)
+                       amodule->got [i] = amodule->shared_got [i];
+       }
+       if (amodule->llvm_got) {
+               for (i = 0; i < N_COMMON_GOT_ENTRIES; ++i)
+                       amodule->llvm_got [i] = amodule->shared_got [i];
+       }
+}
+
 static void
 load_aot_module (MonoAssembly *assembly, gpointer user_data)
 {
@@ -1888,7 +1909,7 @@ load_aot_module (MonoAssembly *assembly, gpointer user_data)
 
        memcpy (&amodule->info, info, sizeof (*info));
 
-       amodule->got = amodule->info.got;
+       amodule->got = amodule->info.jit_got;
        amodule->llvm_got = amodule->info.llvm_got;
        amodule->globals = globals;
        amodule->sofile = sofile;
@@ -1966,6 +1987,9 @@ load_aot_module (MonoAssembly *assembly, gpointer user_data)
        amodule->trampolines [MONO_AOT_TRAMP_IMT_THUNK] = info->imt_thunks;
        amodule->trampolines [MONO_AOT_TRAMP_GSHAREDVT_ARG] = info->gsharedvt_arg_trampolines;
 
+       if (!strcmp (assembly->aname.name, "mscorlib"))
+               mscorlib_aot_module = amodule;
+
        /* Compute code_offsets from the method addresses */
        amodule->code_offsets = g_malloc0 (amodule->info.nmethods * sizeof (gint32));
        for (i = 0; i < amodule->info.nmethods; ++i) {
@@ -2021,7 +2045,7 @@ load_aot_module (MonoAssembly *assembly, gpointer user_data)
 
        assembly->image->aot_module = amodule;
 
-       amodule->got [0] = assembly->image;
+       amodule->shared_got [0] = assembly->image;
 
        if (mono_aot_only) {
                char *code;
@@ -2032,9 +2056,9 @@ load_aot_module (MonoAssembly *assembly, gpointer user_data)
                        /* The second got slot contains the mscorlib got addr */
                        MonoAotModule *mscorlib_amodule = mono_defaults.corlib->aot_module;
 
-                       amodule->got [1] = mscorlib_amodule->got;
+                       amodule->shared_got [1] = mscorlib_amodule->got;
                } else {
-                       amodule->got [1] = amodule->got;
+                       amodule->shared_got [1] = amodule->got;
                }
        }
 
@@ -2043,19 +2067,14 @@ load_aot_module (MonoAssembly *assembly, gpointer user_data)
 
                memset (&ji, 0, sizeof (ji));
                ji.type = MONO_PATCH_INFO_GC_CARD_TABLE_ADDR;
-               amodule->got [2] = mono_resolve_patch_target (NULL, mono_get_root_domain (), NULL, &ji, FALSE);
+               amodule->shared_got [2] = mono_resolve_patch_target (NULL, mono_get_root_domain (), NULL, &ji, FALSE);
 
                memset (&ji, 0, sizeof (ji));
                ji.type = MONO_PATCH_INFO_GC_NURSERY_START;
-               amodule->got [3] = mono_resolve_patch_target (NULL, mono_get_root_domain (), NULL, &ji, FALSE);
+               amodule->shared_got [3] = mono_resolve_patch_target (NULL, mono_get_root_domain (), NULL, &ji, FALSE);
        }
 
-       if (amodule->llvm_got) {
-               amodule->llvm_got [0] = amodule->got [0];
-               amodule->llvm_got [1] = amodule->got [1];
-               amodule->llvm_got [2] = amodule->got [2];
-               amodule->llvm_got [3] = amodule->got [3];
-       }
+       init_gots (amodule);
 
        /*
         * Since we store methoddef and classdef tokens when referring to methods/classes in
@@ -3633,7 +3652,7 @@ load_method (MonoDomain *domain, MonoAotModule *amodule, MonoImage *image, MonoM
                }
        }
 
-       res = mono_aot_init_method (amodule, method_index, method, &klass);
+       res = init_method (amodule, method_index, method, &klass);
        if (!res)
                goto cleanup;
 
@@ -3832,7 +3851,7 @@ mono_aot_find_method_index (MonoMethod *method)
 }
 
 static gboolean
-mono_aot_init_method (MonoAotModule *amodule, guint32 method_index, MonoMethod *method, MonoClass **klass)
+init_method (MonoAotModule *amodule, guint32 method_index, MonoMethod *method, MonoClass **klass)
 {
        MonoDomain *domain = mono_domain_get ();
        MonoMemPool *mp;
@@ -4585,6 +4604,21 @@ load_function (MonoAotModule *amodule, const char *name)
        return load_function_full (amodule, name, NULL);
 }
 
+static MonoAotModule*
+get_mscorlib_aot_module (void)
+{
+       MonoImage *image;
+       MonoAotModule *amodule;
+
+       image = mono_defaults.corlib;
+       if (image)
+               amodule = image->aot_module;
+       else
+               amodule = mscorlib_aot_module;
+       g_assert (amodule);
+       return amodule;
+}
+
 /*
  * Return the trampoline identified by NAME from the mscorlib AOT file.
  * On ppc64, this returns a function descriptor.
@@ -4592,14 +4626,7 @@ load_function (MonoAotModule *amodule, const char *name)
 gpointer
 mono_aot_get_trampoline_full (const char *name, MonoTrampInfo **out_tinfo)
 {
-       MonoImage *image;
-       MonoAotModule *amodule;
-
-       image = mono_defaults.corlib;
-       g_assert (image);
-
-       amodule = image->aot_module;
-       g_assert (amodule);
+       MonoAotModule *amodule = get_mscorlib_aot_module ();
 
        return mono_create_ftnptr_malloc (load_function_full (amodule, name, out_tinfo));
 }
@@ -4788,21 +4815,17 @@ get_new_gsharedvt_arg_trampoline_from_page (gpointer tramp, gpointer arg)
 static gpointer
 get_numerous_trampoline (MonoAotTrampoline tramp_type, int n_got_slots, MonoAotModule **out_amodule, guint32 *got_offset, guint32 *out_tramp_size)
 {
-       MonoAotModule *amodule;
-       int index, tramp_size;
        MonoImage *image;
+       MonoAotModule *amodule = get_mscorlib_aot_module ();
+       int index, tramp_size;
 
        /* Currently, we keep all trampolines in the mscorlib AOT image */
        image = mono_defaults.corlib;
-       g_assert (image);
-
-       mono_aot_lock ();
-
-       amodule = image->aot_module;
-       g_assert (amodule);
 
        *out_amodule = amodule;
 
+       mono_aot_lock ();
+
 #ifdef MONOTOUCH
 #define        MONOTOUCH_TRAMPOLINES_ERROR ". See http://docs.xamarin.com/ios/troubleshooting for instructions on how to fix this condition."
 #else
@@ -4810,7 +4833,7 @@ get_numerous_trampoline (MonoAotTrampoline tramp_type, int n_got_slots, MonoAotM
 #endif
        if (amodule->trampoline_index [tramp_type] == amodule->info.num_trampolines [tramp_type]) {
                g_error ("Ran out of trampolines of type %d in '%s' (%d)%s\n", 
-                                tramp_type, image->name, amodule->info.num_trampolines [tramp_type], MONOTOUCH_TRAMPOLINES_ERROR);
+                                tramp_type, image ? image->name : "mscorlib", amodule->info.num_trampolines [tramp_type], MONOTOUCH_TRAMPOLINES_ERROR);
        }
        index = amodule->trampoline_index [tramp_type] ++;
 

diff --git a/mono/mini/mini.h b/mono/mini/mini.h
index 84a3f47244354841346f020eaf99c8d71b95b941..ca0b7ab2ebd347c4fbd59cfcf3cd62fdf9263e44 100644 (file)
--- a/mono/mini/mini.h
+++ b/mono/mini/mini.h
@@ -189,8 +189,8 @@ typedef struct MonoAotFileInfo
 
        /* All the pointers should be at the start to avoid alignment problems */
 
-       /* Mono's Global Offset Table */
-       gpointer got;
+       /* Global Offset Table for JITted code */
+       gpointer jit_got;
        /* Global Offset Table for LLVM code */
        gpointer llvm_got;
        /* Compiled code for methods */