Merge pull request #820 from brendanzagaeski/master
[mono.git] / mono / mini / dwarfwriter.c
index 222b4a392db59daf5d3a8f506a50d170227a6e8b..7542f49aa75d234f995cf7834b667a5f00bb3d9a 100644 (file)
 
 #include <mono/utils/freebsd-dwarf.h>
 
+typedef struct {
+       MonoMethod *method;
+       char *start_symbol, *end_symbol;
+       guint8 *code;
+       guint32 code_size;
+} MethodLineNumberInfo;
+
 struct _MonoDwarfWriter
 {
        MonoImageWriter *w;
        GHashTable *class_to_die, *class_to_vtype_die, *class_to_pointer_die;
        GHashTable *class_to_reference_die;
        int fde_index, tdie_index, line_number_file_index, line_number_dir_index;
-       GHashTable *file_to_index, *dir_to_index;
+       GHashTable *file_to_index, *index_to_file, *dir_to_index;
        FILE *il_file;
        int il_file_line_index, loclist_index;
        GSList *cie_program;
        FILE *fp;
        const char *temp_prefix;
-       gboolean emit_line, appending;
+       gboolean emit_line, appending, collect_line_info;
+       GSList *line_info;
+       int cur_file_index;
 };
 
+static void
+emit_line_number_info (MonoDwarfWriter *w, MonoMethod *method, 
+                                          char *start_symbol, char *end_symbol,
+                                          guint8 *code, guint32 code_size,
+                                          MonoDebugMethodJitInfo *debug_info);
+
 /*
  * mono_dwarf_writer_create:
  *
@@ -57,7 +72,7 @@ struct _MonoDwarfWriter
  * debug information.
  */
 MonoDwarfWriter*
-mono_dwarf_writer_create (MonoImageWriter *writer, FILE *il_file, int il_file_start_line, gboolean appending)
+mono_dwarf_writer_create (MonoImageWriter *writer, FILE *il_file, int il_file_start_line, gboolean appending, gboolean emit_line_numbers)
 {
        MonoDwarfWriter *w = g_new0 (MonoDwarfWriter, 1);
        
@@ -78,9 +93,31 @@ mono_dwarf_writer_create (MonoImageWriter *writer, FILE *il_file, int il_file_st
        if (appending)
                g_assert (img_writer_subsections_supported (w->w));
 
+       w->emit_line = TRUE;
+
+       if (appending) {
+               if (!img_writer_subsections_supported (w->w))
+                       /* Can't emit line number info without subsections */
+                       w->emit_line = FALSE;
+       } else {
+               /* Collect line number info and emit it at once */
+               w->collect_line_info = TRUE;
+       }
+
+       if (!emit_line_numbers) {
+               w->emit_line = FALSE;
+               w->collect_line_info = FALSE;
+       }
+
        w->fp = img_writer_get_fp (w->w);
        w->temp_prefix = img_writer_get_temp_label_prefix (w->w);
 
+       w->class_to_die = g_hash_table_new (NULL, NULL);
+       w->class_to_vtype_die = g_hash_table_new (NULL, NULL);
+       w->class_to_pointer_die = g_hash_table_new (NULL, NULL);
+       w->class_to_reference_die = g_hash_table_new (NULL, NULL);
+       w->cur_file_index = -1;
+
        return w;
 }
 
@@ -404,6 +441,7 @@ emit_fde (MonoDwarfWriter *w, int fde_index, char *start_symbol, char *end_symbo
 #define ABBREV_PARAM_LOCLIST 15
 #define ABBREV_INHERITANCE 16
 #define ABBREV_STRUCT_TYPE_NOCHILDREN 17
+#define ABBREV_TRAMP_SUBPROGRAM 18
 
 static int compile_unit_attr [] = {
        DW_AT_producer     ,DW_FORM_string,
@@ -417,11 +455,20 @@ static int compile_unit_attr [] = {
 
 static int subprogram_attr [] = {
        DW_AT_name         , DW_FORM_string,
+#ifndef TARGET_IOS
+       DW_AT_description  , DW_FORM_string,
+#endif
     DW_AT_low_pc       , DW_FORM_addr,
     DW_AT_high_pc      , DW_FORM_addr,
        DW_AT_frame_base   , DW_FORM_block1
 };
 
+static int tramp_subprogram_attr [] = {
+       DW_AT_name         , DW_FORM_string,
+    DW_AT_low_pc       , DW_FORM_addr,
+    DW_AT_high_pc      , DW_FORM_addr,
+};
+
 static int param_attr [] = {
        DW_AT_name,     DW_FORM_string,
        DW_AT_type,     DW_FORM_ref4,
@@ -593,21 +640,125 @@ emit_line_number_file_name (MonoDwarfWriter *w, const char *name,
        return index;
 }
 
+static int
+get_line_number_file_name (MonoDwarfWriter *w, const char *name)
+{
+       int index;
+
+       g_assert (w->file_to_index);
+       index = GPOINTER_TO_UINT (g_hash_table_lookup (w->file_to_index, name));
+       g_assert (index > 0);
+       return index - 1;
+}
+
+static int
+add_line_number_file_name (MonoDwarfWriter *w, const char *name,
+                                                  gint64 last_mod_time, gint64 file_size)
+{
+       int index;
+       char *copy;
+
+       if (!w->file_to_index) {
+               w->file_to_index = g_hash_table_new (g_str_hash, g_str_equal);
+               w->index_to_file = g_hash_table_new (NULL, NULL);
+       }
+
+       index = GPOINTER_TO_UINT (g_hash_table_lookup (w->file_to_index, name));
+       if (index > 0)
+               return index - 1;
+       index = w->line_number_file_index;
+       w->line_number_file_index ++;
+       copy = g_strdup (name);
+       g_hash_table_insert (w->file_to_index, copy, GUINT_TO_POINTER (index + 1));
+       g_hash_table_insert (w->index_to_file, GUINT_TO_POINTER (index + 1), copy);
+
+       return index;
+}
+
+char *
+mono_dwarf_escape_path (const char *name)
+{
+       if (strchr (name, '\\')) {
+               char *s;
+               int len, i, j;
+
+               len = strlen (name);
+               s = g_malloc0 ((len + 1) * 2);
+               j = 0;
+               for (i = 0; i < len; ++i) {
+                       if (name [i] == '\\') {
+                               s [j ++] = '\\';
+                               s [j ++] = '\\';
+                       } else {
+                               s [j ++] = name [i];
+                       }
+               }
+               return s;
+       }
+       return g_strdup (name);
+}
+
 static void
-emit_line_number_info_begin (MonoDwarfWriter *w)
+emit_all_line_number_info (MonoDwarfWriter *w)
 {
+       int i;
+       GHashTable *dir_to_index, *index_to_dir;
+       GSList *l;
+       GSList *info_list;
+
+       g_assert (w->collect_line_info);
+
+       add_line_number_file_name (w, "<unknown>", 0, 0);
+
+       /* Collect files */
+       info_list = g_slist_reverse (w->line_info);
+       for (l = info_list; l; l = l->next) {
+               MethodLineNumberInfo *info = l->data;
+               MonoDebugMethodInfo *minfo;
+               char *source_file;
+               GPtrArray *source_file_list;
+
+               // FIXME: Free stuff
+               minfo = mono_debug_lookup_method (info->method);
+               if (!minfo)
+                       continue;
+
+               mono_debug_symfile_get_line_numbers_full (minfo, &source_file, &source_file_list, NULL, NULL, NULL, NULL, NULL);
+               for (i = 0; i < source_file_list->len; ++i) {
+                       MonoDebugSourceInfo *sinfo = g_ptr_array_index (source_file_list, i);
+                       add_line_number_file_name (w, sinfo->source_file, 0, 0);
+               }
+       }               
+
+       /* Preprocess files */
+       dir_to_index = g_hash_table_new (g_str_hash, g_str_equal);
+       index_to_dir = g_hash_table_new (NULL, NULL);
+       for (i = 0; i < w->line_number_file_index; ++i) {
+               char *name = g_hash_table_lookup (w->index_to_file, GUINT_TO_POINTER (i + 1));
+               char *copy;
+               int dir_index = 0;
+
+               if (g_path_is_absolute (name)) {
+                       char *dir = g_path_get_dirname (name);
+
+                       dir_index = GPOINTER_TO_UINT (g_hash_table_lookup (dir_to_index, dir));
+                       if (dir_index == 0) {
+                               dir_index = w->line_number_dir_index;
+                               w->line_number_dir_index ++;
+                               copy = g_strdup (dir);
+                               g_hash_table_insert (dir_to_index, copy, GUINT_TO_POINTER (dir_index + 1));
+                               g_hash_table_insert (index_to_dir, GUINT_TO_POINTER (dir_index + 1), copy);
+                       } else {
+                               dir_index --;
+                       }
+
+                       g_free (dir);
+               }
+       }
+
        /* Line number info header */
-       /* 
-        * GAS seems to emit its own data to the end of the first subsection, so we use
-        * subsections 1, 2 etc:
-        * 1 - contains the header
-        * 2 - contains the file names
-        * 3 - contains the end of the header + the data
-        * 4 - the end symbol
-        */
        emit_section_change (w, ".debug_line", 0);
        emit_label (w, ".Ldebug_line_section_start");
-       emit_section_change (w, ".debug_line", LINE_SUBSECTION_HEADER);
        emit_label (w, ".Ldebug_line_start");
        emit_symbol_diff (w, ".Ldebug_line_end", ".", -4); /* length */
        emit_int16 (w, 0x2); /* version */
@@ -631,23 +782,52 @@ emit_line_number_info_begin (MonoDwarfWriter *w)
        emit_byte (w, 1);
 
        /* Includes */
-       emit_section_change (w, ".debug_line", LINE_SUBSECTION_INCLUDES);
+       emit_section_change (w, ".debug_line", 0);
+       for (i = 0; i < w->line_number_dir_index; ++i) {
+               char *dir = g_hash_table_lookup (index_to_dir, GUINT_TO_POINTER (i + 1));
 
+               emit_string (w, mono_dwarf_escape_path (dir));
+       }
        /* End of Includes */
-       emit_section_change (w, ".debug_line", LINE_SUBSECTION_FILES);
        emit_byte (w, 0);
 
        /* Files */
-       emit_line_number_file_name (w, "xdb.il", 0, 0);
+       for (i = 0; i < w->line_number_file_index; ++i) {
+               char *name = g_hash_table_lookup (w->index_to_file, GUINT_TO_POINTER (i + 1));
+               char *basename = NULL, *dir;
+               int dir_index = 0;
+
+               if (g_path_is_absolute (name)) {
+                       dir = g_path_get_dirname (name);
+
+                       dir_index = GPOINTER_TO_UINT (g_hash_table_lookup (dir_to_index, dir));
+                       basename = g_path_get_basename (name);
+               }
+                                                                                        
+               if (basename)
+                       emit_string (w, basename);
+               else
+                       emit_string (w, mono_dwarf_escape_path (name));
+               emit_uleb128 (w, dir_index);
+               emit_byte (w, 0);
+               emit_byte (w, 0);
+       }
 
        /* End of Files */
-       emit_section_change (w, ".debug_line", LINE_SUBSECTION_DATA);
        emit_byte (w, 0);
 
        emit_label (w, ".Ldebug_line_header_end");
 
-       /* Emit this into a separate subsection so it gets placed at the end */ 
-       emit_section_change (w, ".debug_line", LINE_SUBSECTION_END);
+       /* Emit line number table */
+       for (l = info_list; l; l = l->next) {
+               MethodLineNumberInfo *info = l->data;
+               MonoDebugMethodJitInfo *dmji;
+
+               dmji = mono_debug_find_method (info->method, mono_domain_get ());;
+               emit_line_number_info (w, info->method, info->start_symbol, info->end_symbol, info->code, info->code_size, dmji);
+               mono_debug_free_method_jit_info (dmji);
+       }
+       g_slist_free (info_list);
 
        emit_byte (w, 0);
        emit_byte (w, 1);
@@ -673,17 +853,11 @@ emit_debug_info_end (MonoDwarfWriter *w)
 }
 
 void
-mono_dwarf_writer_emit_base_info (MonoDwarfWriter *w, GSList *base_unwind_program)
+mono_dwarf_writer_emit_base_info (MonoDwarfWriter *w, const char *cu_name, GSList *base_unwind_program)
 {
        char *s, *build_info;
        int i;
 
-       if (!img_writer_subsections_supported (w->w))
-               /* Can't emit line number info without subsections */
-               w->emit_line = FALSE;
-       else
-               w->emit_line = TRUE;
-
        w->cie_program = base_unwind_program;
 
        emit_section_change (w, ".debug_abbrev", 0);
@@ -721,6 +895,8 @@ mono_dwarf_writer_emit_base_info (MonoDwarfWriter *w, GSList *base_unwind_progra
                                           reference_type_attr, G_N_ELEMENTS (reference_type_attr));
        emit_dwarf_abbrev (w, ABBREV_INHERITANCE, DW_TAG_inheritance, FALSE,
                                           inheritance_attr, G_N_ELEMENTS (inheritance_attr));
+       emit_dwarf_abbrev (w, ABBREV_TRAMP_SUBPROGRAM, DW_TAG_subprogram, FALSE,
+                                          tramp_subprogram_attr, G_N_ELEMENTS (tramp_subprogram_attr));
        emit_byte (w, 0);
 
        emit_section_change (w, ".debug_info", 0);
@@ -746,13 +922,16 @@ mono_dwarf_writer_emit_base_info (MonoDwarfWriter *w, GSList *base_unwind_progra
        emit_string (w, s);
        g_free (build_info);
        g_free (s);
-       emit_string (w, "JITted code");
+       emit_string (w, cu_name);
        emit_string (w, "");
        emit_byte (w, DW_LANG_C);
        emit_pointer_value (w, 0);
        emit_pointer_value (w, 0);
        /* offset into .debug_line section */
-       emit_symbol_diff (w, ".Ldebug_line_start", ".Ldebug_line_section_start", 0);
+       if (w->emit_line)
+               emit_symbol_diff (w, ".Ldebug_line_start", ".Ldebug_line_section_start", 0);
+       else
+               emit_pointer_value (w, 0);
 
        /* Base types */
        for (i = 0; i < G_N_ELEMENTS (basic_types); ++i) {
@@ -769,13 +948,6 @@ mono_dwarf_writer_emit_base_info (MonoDwarfWriter *w, GSList *base_unwind_progra
        emit_section_change (w, ".debug_loc", 0);
        emit_label (w, ".Ldebug_loc_start");
 
-       /* debug_line section */
-       /*
-        * We emit some info even if emit_line is FALSE, as the
-        * apple linker seems to require a .debug_line section.
-        */
-       emit_line_number_info_begin (w);
-
        emit_cie (w);
 }
 
@@ -792,9 +964,26 @@ mono_dwarf_writer_close (MonoDwarfWriter *w)
                emit_byte (w, 0); /* close COMPILE_UNIT */
                emit_label (w, ".Ldebug_info_end");
        }
+
+       if (w->collect_line_info)
+               emit_all_line_number_info (w);
 }
 
-static const char* emit_type (MonoDwarfWriter *w, MonoType *t);
+static void emit_type (MonoDwarfWriter *w, MonoType *t);
+static const char* get_type_die (MonoDwarfWriter *w, MonoType *t);
+
+static const char*
+get_class_die (MonoDwarfWriter *w, MonoClass *klass, gboolean vtype)
+{
+       GHashTable *cache;
+
+       if (vtype)
+               cache = w->class_to_vtype_die;
+       else
+               cache = w->class_to_die;
+
+       return g_hash_table_lookup (cache, klass);
+}
 
 /* Returns the local symbol pointing to the emitted debug info */
 static char*
@@ -809,16 +998,6 @@ emit_class_dwarf_info (MonoDwarfWriter *w, MonoClass *klass, gboolean vtype)
        gboolean emit_namespace = FALSE, has_children;
        GHashTable *cache;
 
-       // FIXME: Appdomains
-       if (!w->class_to_die)
-               w->class_to_die = g_hash_table_new (NULL, NULL);
-       if (!w->class_to_vtype_die)
-               w->class_to_vtype_die = g_hash_table_new (NULL, NULL);
-       if (!w->class_to_pointer_die)
-               w->class_to_pointer_die = g_hash_table_new (NULL, NULL);
-       if (!w->class_to_reference_die)
-               w->class_to_reference_die = g_hash_table_new (NULL, NULL);
-
        if (vtype)
                cache = w->class_to_vtype_die;
        else
@@ -828,7 +1007,8 @@ emit_class_dwarf_info (MonoDwarfWriter *w, MonoClass *klass, gboolean vtype)
        if (die)
                return die;
 
-       if (!((klass->byval_arg.type == MONO_TYPE_CLASS) || (klass->byval_arg.type == MONO_TYPE_OBJECT) || klass->byval_arg.type == MONO_TYPE_GENERICINST || klass->enumtype || (klass->byval_arg.type == MONO_TYPE_VALUETYPE && vtype)))
+       if (!((klass->byval_arg.type == MONO_TYPE_CLASS) || (klass->byval_arg.type == MONO_TYPE_OBJECT) || klass->byval_arg.type == MONO_TYPE_GENERICINST || klass->enumtype || (klass->byval_arg.type == MONO_TYPE_VALUETYPE && vtype) ||
+                 (klass->byval_arg.type >= MONO_TYPE_BOOLEAN && klass->byval_arg.type <= MONO_TYPE_R8 && !vtype)))
                return NULL;
 
        /*
@@ -970,7 +1150,7 @@ emit_class_dwarf_info (MonoDwarfWriter *w, MonoClass *klass, gboolean vtype)
                        if (field->type->attrs & FIELD_ATTRIBUTE_STATIC)
                                continue;
 
-                       fdie = emit_type (w, field->type);
+                       fdie = get_type_die (w, field->type);
                        if (fdie) {
                                emit_uleb128 (w, ABBREV_DATA_MEMBER);
                                emit_string (w, field->name);
@@ -1020,8 +1200,10 @@ emit_class_dwarf_info (MonoDwarfWriter *w, MonoClass *klass, gboolean vtype)
        return die;
 }
 
+static gboolean base_types_emitted [64];
+
 static const char*
-emit_type (MonoDwarfWriter *w, MonoType *t)
+get_type_die (MonoDwarfWriter *w, MonoType *t)
 {
        MonoClass *klass = mono_class_from_mono_type (t);
        int j;
@@ -1029,12 +1211,10 @@ emit_type (MonoDwarfWriter *w, MonoType *t)
 
        if (t->byref) {
                if (t->type == MONO_TYPE_VALUETYPE) {
-                       tdie = emit_class_dwarf_info (w, klass, TRUE);
-                       if (tdie)
-                               return g_hash_table_lookup (w->class_to_pointer_die, klass);
+                       tdie = g_hash_table_lookup (w->class_to_pointer_die, klass);
                }
                else {
-                       tdie = emit_class_dwarf_info (w, klass, FALSE);
+                       tdie = get_class_die (w, klass, FALSE);
                        /* Should return a pointer type to a reference */
                }
                // FIXME:
@@ -1043,12 +1223,11 @@ emit_type (MonoDwarfWriter *w, MonoType *t)
        for (j = 0; j < G_N_ELEMENTS (basic_types); ++j)
                if (basic_types [j].type == t->type)
                        break;
-       if (j < G_N_ELEMENTS (basic_types))
+       if (j < G_N_ELEMENTS (basic_types)) {
                tdie = basic_types [j].die_name;
-       else {
+       else {
                switch (t->type) {
                case MONO_TYPE_CLASS:
-                       emit_class_dwarf_info (w, klass, FALSE);
                        tdie = g_hash_table_lookup (w->class_to_reference_die, klass);
                        //tdie = ".LDIE_OBJECT";
                        break;
@@ -1057,13 +1236,12 @@ emit_type (MonoDwarfWriter *w, MonoType *t)
                        break;
                case MONO_TYPE_VALUETYPE:
                        if (klass->enumtype)
-                               tdie = emit_class_dwarf_info (w, klass, FALSE);
+                               tdie = get_class_die (w, klass, FALSE);
                        else
                                tdie = ".LDIE_I4";
                        break;
                case MONO_TYPE_GENERICINST:
                        if (!MONO_TYPE_ISSTRUCT (t)) {
-                               emit_class_dwarf_info (w, klass, FALSE);
                                tdie = g_hash_table_lookup (w->class_to_reference_die, klass);
                        } else {
                                tdie = ".LDIE_I4";
@@ -1078,15 +1256,68 @@ emit_type (MonoDwarfWriter *w, MonoType *t)
                }
        }
 
+       g_assert (tdie);
+
        return tdie;
 }
 
+static void
+emit_type (MonoDwarfWriter *w, MonoType *t)
+{
+       MonoClass *klass = mono_class_from_mono_type (t);
+       int j;
+       const char *tdie;
+
+       if (t->byref) {
+               if (t->type == MONO_TYPE_VALUETYPE) {
+                       tdie = emit_class_dwarf_info (w, klass, TRUE);
+                       if (tdie)
+                               return;
+               }
+               else {
+                       emit_class_dwarf_info (w, klass, FALSE);
+               }
+               // FIXME:
+               t = &mono_defaults.int_class->byval_arg;
+       }
+       for (j = 0; j < G_N_ELEMENTS (basic_types); ++j)
+               if (basic_types [j].type == t->type)
+                       break;
+       if (j < G_N_ELEMENTS (basic_types)) {
+               /* Emit a boxed version of base types */
+               if (j < 64 && !base_types_emitted [j]) {
+                       emit_class_dwarf_info (w, klass, FALSE);
+                       base_types_emitted [j] = TRUE;
+               }
+       } else {
+               switch (t->type) {
+               case MONO_TYPE_CLASS:
+                       emit_class_dwarf_info (w, klass, FALSE);
+                       break;
+               case MONO_TYPE_ARRAY:
+                       break;
+               case MONO_TYPE_VALUETYPE:
+                       if (klass->enumtype)
+                               emit_class_dwarf_info (w, klass, FALSE);
+                       break;
+               case MONO_TYPE_GENERICINST:
+                       if (!MONO_TYPE_ISSTRUCT (t))
+                               emit_class_dwarf_info (w, klass, FALSE);
+                       break;
+               case MONO_TYPE_PTR:
+                       break;
+               default:
+                       break;
+               }
+       }
+}
+
 static void
 emit_var_type (MonoDwarfWriter *w, MonoType *t)
 {
        const char *tdie;
 
-       tdie = emit_type (w, t);
+       tdie = get_type_die (w, t);
 
        emit_symbol_diff (w, tdie, ".Ldebug_info_start", 0);
 }
@@ -1307,6 +1538,7 @@ emit_advance_op (MonoDwarfWriter *w, int line_diff, int addr_diff)
        if (opcode != 0) {
                emit_byte (w, opcode);
        } else {
+               //printf ("large: %d %d %d\n", line_diff, addr_diff, max_special_addr_diff);
                emit_byte (w, DW_LNS_advance_line);
                emit_sleb128 (w, line_diff);
                emit_byte (w, DW_LNS_advance_pc);
@@ -1340,7 +1572,7 @@ emit_line_number_info (MonoDwarfWriter *w, MonoMethod *method,
        MonoDebugMethodInfo *minfo;
        MonoDebugLineNumberEntry *ln_array;
        int *native_to_il_offset = NULL;
-
+       
        if (!w->emit_line) {
                mono_metadata_free_mh (header);
                return;
@@ -1383,7 +1615,10 @@ emit_line_number_info (MonoDwarfWriter *w, MonoMethod *method,
        prev_line = 1;
        prev_il_offset = -1;
 
+       w->cur_file_index = -1;
        for (i = 0; i < code_size; ++i) {
+               int line_diff, addr_diff;
+
                if (!minfo)
                        continue;
 
@@ -1410,59 +1645,63 @@ emit_line_number_info (MonoDwarfWriter *w, MonoMethod *method,
                prev_il_offset = il_offset;
 
                loc = mono_debug_symfile_lookup_location (minfo, il_offset);
+               if (!(loc && loc->source_file))
+                       continue;
 
-               // Added the loc->source_file check as otherwise we can
-               // crash, see the sample in bug 553191 that makes this code
-               // crash when we call strcmp on loc->source_file below
-               if (loc && loc->source_file) {
-                       int line_diff = (gint32)loc->row - (gint32)prev_line;
-                       int addr_diff = i - prev_native_offset;
-
-                       if (first) {    
-                               emit_section_change (w, ".debug_line", LINE_SUBSECTION_DATA);
-
-                               emit_byte (w, 0);
-                               emit_byte (w, sizeof (gpointer) + 1);
-                               emit_byte (w, DW_LNE_set_address);
-                               if (start_symbol)
-                                       emit_pointer_unaligned (w, start_symbol);
-                               else
-                                       emit_pointer_value (w, code);
+               line_diff = (gint32)loc->row - (gint32)prev_line;
+               addr_diff = i - prev_native_offset;
 
-                               /* 
-                                * The prolog+initlocals region does not have a line number, this
-                                * makes them belong to the first line of the method.
-                                */
-                               emit_byte (w, DW_LNS_advance_line);
-                               emit_sleb128 (w, (gint32)loc->row - (gint32)prev_line);
-                               prev_line = loc->row;
-                       }
+               if (first) {    
+                       emit_section_change (w, ".debug_line", LINE_SUBSECTION_DATA);
+
+                       emit_byte (w, 0);
+                       emit_byte (w, sizeof (gpointer) + 1);
+                       emit_byte (w, DW_LNE_set_address);
+                       if (start_symbol)
+                               emit_pointer_unaligned (w, start_symbol);
+                       else
+                               emit_pointer_value (w, code);
+
+                       /* 
+                        * The prolog+initlocals region does not have a line number, this
+                        * makes them belong to the first line of the method.
+                        */
+                       emit_byte (w, DW_LNS_advance_line);
+                       //printf ("FIRST: %d %d %d\n", prev_line, loc->row, il_offset);
+                       emit_sleb128 (w, (gint32)loc->row - (gint32)prev_line);
+                       first = FALSE;
+               }
 
-                       if (loc->row != prev_line) {
-                               if (!prev_file_name || strcmp (loc->source_file, prev_file_name) != 0) {
-                                       /* Add an entry to the file table */
-                                       /* FIXME: Avoid duplicates */
+               if (loc->row != prev_line) {
+                       if (!prev_file_name || strcmp (loc->source_file, prev_file_name) != 0) {
+                               /* Add an entry to the file table */
+                               /* FIXME: Avoid duplicates */
+                               if (w->collect_line_info)
+                                       file_index = get_line_number_file_name (w, loc->source_file) + 1;
+                               else
                                        file_index = emit_line_number_file_name (w, loc->source_file, 0, 0);
-                                       g_free (prev_file_name);
-                                       prev_file_name = g_strdup (loc->source_file);
+                               g_free (prev_file_name);
+                               prev_file_name = g_strdup (loc->source_file);
 
+                               if (w->cur_file_index != file_index) {
                                        emit_byte (w, DW_LNS_set_file);
                                        emit_uleb128 (w, file_index);
                                        emit_byte (w, DW_LNS_copy);
-                               }
-
-                               //printf ("X: %p(+0x%x) %d %s:%d(+%d)\n", code + i, addr_diff, loc->il_offset, loc->source_file, loc->row, line_diff);
-
-                               emit_advance_op (w, line_diff, addr_diff);
-
-                               prev_line = loc->row;
-                               prev_native_offset = i;
+                                       w->cur_file_index = file_index;
+                               }                                       
                        }
+               }
 
-                       first = FALSE;
+               if (loc->row != prev_line && !first) {
+                       //printf ("X: %p(+0x%x) %d %s:%d(+%d)\n", code + i, addr_diff, loc->il_offset, loc->source_file, loc->row, line_diff);
+                       emit_advance_op (w, line_diff, addr_diff);
 
-                       mono_debug_symfile_free_location (loc);
+                       prev_line = loc->row;
+                       prev_native_offset = i;
                }
+
+               mono_debug_symfile_free_location (loc);
+               first = FALSE;
        }
 
        g_free (native_to_il_offset);
@@ -1611,6 +1850,7 @@ mono_dwarf_writer_emit_method (MonoDwarfWriter *w, MonoCompile *cfg, MonoMethod
 
                emit_type (w, t);
        }
+       //emit_type (w, &mono_defaults.int32_class->byval_arg);
 
        /* Local types */
        for (i = 0; i < header->num_locals; ++i) {
@@ -1624,6 +1864,9 @@ mono_dwarf_writer_emit_method (MonoDwarfWriter *w, MonoCompile *cfg, MonoMethod
        emit_uleb128 (w, ABBREV_SUBPROGRAM);
        name = mono_method_full_name (method, FALSE);
        emit_string (w, name);
+#ifndef TARGET_IOS
+       emit_string (w, name);
+#endif
        g_free (name);
        if (start_symbol) {
                emit_pointer_unaligned (w, start_symbol);
@@ -1763,8 +2006,22 @@ mono_dwarf_writer_emit_method (MonoDwarfWriter *w, MonoCompile *cfg, MonoMethod
 
        /* Emit line number info */
        /* != could happen when using --regression */
-       if (debug_info && (debug_info->code_start == code))
-               emit_line_number_info (w, method, start_symbol, end_symbol, code, code_size, debug_info);
+       if (debug_info && (debug_info->code_start == code)) {
+               if (w->collect_line_info) {
+                       MethodLineNumberInfo *info;
+
+                       /* Save the information needed to emit the line number info later at once */
+                       info = g_new0 (MethodLineNumberInfo, 1);
+                       info->method = method;
+                       info->start_symbol = g_strdup (start_symbol);
+                       info->end_symbol = g_strdup (end_symbol);
+                       info->code = code;
+                       info->code_size = code_size;
+                       w->line_info = g_slist_prepend (w->line_info, info);
+               } else {
+                       emit_line_number_info (w, method, start_symbol, end_symbol, code, code_size, debug_info);
+               }
+       }
 
        emit_line (w);
        mono_metadata_free_mh (header);
@@ -1776,14 +2033,10 @@ mono_dwarf_writer_emit_trampoline (MonoDwarfWriter *w, const char *tramp_name, c
        emit_section_change (w, ".debug_info", 0);
 
        /* Subprogram */
-       emit_uleb128 (w, ABBREV_SUBPROGRAM);
+       emit_uleb128 (w, ABBREV_TRAMP_SUBPROGRAM);
        emit_string (w, tramp_name);
        emit_pointer_value (w, code);
        emit_pointer_value (w, code + code_size);
-       /* frame_base */
-       emit_byte (w, 2);
-       emit_byte (w, DW_OP_breg6);
-       emit_byte (w, 16);
 
        /* Subprogram end */
        emit_uleb128 (w, 0x0);