Embed Backtrace objects

rb_backtrace_t is 32B, so it fits well in a 80B slot.

There is some unused spaces but given Backtrace objects are
rarely held onto it should be inconsequential and avoid
the malloc churn.

Co-Authored-By: Étienne Barrié <etienne.barrie@gmail.com>

1 files changed, 10 insertions, 11 deletions

diff --git a/vm_backtrace.c b/vm_backtrace.c
index 551fdad0d1..6f986341aa 100644
--- a/vm_backtrace.c
+++ b/vm_backtrace.c
@@ -478,7 +478,6 @@ backtrace_free(void *ptr)
 {
    rb_backtrace_t *bt = (rb_backtrace_t *)ptr;
    ruby_xfree(bt->backtrace);
-   ruby_xfree(bt);
 }
 
 static void
@@ -515,13 +514,13 @@ static size_t
 backtrace_memsize(const void *ptr)
 {
     rb_backtrace_t *bt = (rb_backtrace_t *)ptr;
-    return sizeof(rb_backtrace_t) + sizeof(rb_backtrace_location_t) * bt->backtrace_size;
+    return sizeof(rb_backtrace_location_t) * bt->backtrace_size;
 }
 
 static const rb_data_type_t backtrace_data_type = {
     "backtrace",
     {backtrace_mark, backtrace_free, backtrace_memsize, backtrace_update},
-    0, 0, RUBY_TYPED_FREE_IMMEDIATELY | RUBY_TYPED_WB_PROTECTED
+    0, 0, RUBY_TYPED_FREE_IMMEDIATELY | RUBY_TYPED_WB_PROTECTED | RUBY_TYPED_EMBEDDABLE
 };
 
 int
@@ -595,9 +594,9 @@ rb_ec_partial_backtrace_object(const rb_execution_context_t *ec, long start_fram
     ptrdiff_t size;
     rb_backtrace_t *bt;
     VALUE btobj = backtrace_alloc(rb_cBacktrace);
+    TypedData_Get_Struct(btobj, rb_backtrace_t, &backtrace_data_type, bt);
     rb_backtrace_location_t *loc = NULL;
     unsigned long cfunc_counter = 0;
-    GetCoreDataFromValue(btobj, rb_backtrace_t, bt);
 
     // In the case the thread vm_stack or cfp is not initialized, there is no backtrace.
     if (end_cfp == NULL) {
@@ -625,8 +624,8 @@ rb_ec_partial_backtrace_object(const rb_execution_context_t *ec, long start_fram
         }
     }
 
-    bt->backtrace = ZALLOC_N(rb_backtrace_location_t, num_frames);
     bt->backtrace_size = 0;
+    bt->backtrace = ZALLOC_N(rb_backtrace_location_t, num_frames);
     if (num_frames == 0) {
         if (start_too_large) *start_too_large = 0;
         return btobj;
@@ -719,7 +718,7 @@ backtrace_to_str_ary(VALUE self)
 {
     VALUE r;
     rb_backtrace_t *bt;
-    GetCoreDataFromValue(self, rb_backtrace_t, bt);
+    TypedData_Get_Struct(self, rb_backtrace_t, &backtrace_data_type, bt);
     r = backtrace_collect(bt, location_to_str_dmyarg, 0);
     RB_GC_GUARD(self);
     return r;
@@ -729,7 +728,7 @@ VALUE
 rb_backtrace_to_str_ary(VALUE self)
 {
     rb_backtrace_t *bt;
-    GetCoreDataFromValue(self, rb_backtrace_t, bt);
+    TypedData_Get_Struct(self, rb_backtrace_t, &backtrace_data_type, bt);
 
     if (!bt->strary) {
         RB_OBJ_WRITE(self, &bt->strary, backtrace_to_str_ary(self));
@@ -743,7 +742,7 @@ rb_backtrace_use_iseq_first_lineno_for_last_location(VALUE self)
     const rb_backtrace_t *bt;
     rb_backtrace_location_t *loc;
 
-    GetCoreDataFromValue(self, rb_backtrace_t, bt);
+    TypedData_Get_Struct(self, rb_backtrace_t, &backtrace_data_type, bt);
     VM_ASSERT(bt->backtrace_size > 0);
 
     loc = &bt->backtrace[0];
@@ -771,7 +770,7 @@ backtrace_to_location_ary(VALUE self)
 {
     VALUE r;
     rb_backtrace_t *bt;
-    GetCoreDataFromValue(self, rb_backtrace_t, bt);
+    TypedData_Get_Struct(self, rb_backtrace_t, &backtrace_data_type, bt);
     r = backtrace_collect(bt, location_create, (void *)self);
     RB_GC_GUARD(self);
     return r;
@@ -781,7 +780,7 @@ VALUE
 rb_backtrace_to_location_ary(VALUE self)
 {
     rb_backtrace_t *bt;
-    GetCoreDataFromValue(self, rb_backtrace_t, bt);
+    TypedData_Get_Struct(self, rb_backtrace_t, &backtrace_data_type, bt);
 
     if (!bt->locary) {
         RB_OBJ_WRITE(self, &bt->locary, backtrace_to_location_ary(self));
@@ -800,7 +799,7 @@ static VALUE
 backtrace_load_data(VALUE self, VALUE str)
 {
     rb_backtrace_t *bt;
-    GetCoreDataFromValue(self, rb_backtrace_t, bt);
+    TypedData_Get_Struct(self, rb_backtrace_t, &backtrace_data_type, bt);
     RB_OBJ_WRITE(self, &bt->strary, str);
     return self;
 }