[GR-17457] Remove overhead when using RDATA_PTR.

PullRequest: truffleruby/3238

Author: aardvark179

CHANGELOG.md

@@ -56,6 +56,7 @@ Performance:
 * Rewrote `ArrayEachIteratorNode` to optimize performance for a constant-sized array and reduce specializations to 1 general case (#2587, @MattAlp)
 * Reduce conversion of `VALUE`s to native handle during common operations in C extensions (@aardvark179).
 * Improved performance of regex boolean matches (e.g., `Regexp#match?`) by avoiding match data allocation in TRegex (#2558, @nirvdrum).
+* Remove overhead when getting using `RDATA_PTR` (@aardvark179).
 
 Changes:
 

lib/cext/ABI_version.txt

@@ -1 +1 @@
-13
+14

lib/cext/include/ruby/internal/core/rdata.h

@@ -138,7 +138,7 @@ static inline void *
 rb_data_object_get(VALUE obj)
 {
 #ifdef TRUFFLERUBY
-    return DATA_PTR(obj);
+    return polyglot_invoke(RUBY_CEXT, "RDATA_PTR", rb_tr_unwrap(obj));
 #else
     Check_Type(obj, RUBY_T_DATA);
     return DATA_PTR(obj);

lib/truffle/truffle/cext_structs.rb

@@ -22,6 +22,16 @@ def RDATA(object)
     RData.new(object, data_holder)
   end
 
+  def RDATA_PTR(object)
+    # A specialized version of rb_check_type(object, T_DATA)
+    data_holder = Primitive.object_hidden_var_get(object, DATA_HOLDER)
+    unless data_holder
+      raise TypeError, "wrong argument type #{object.class} (expected T_DATA)"
+    end
+
+    data_holder.data
+  end
+
   def RBASIC(object)
     if Primitive.immediate_value?(object)
       raise TypeError, "immediate values don't include the RBasic struct"