vm_insnhelper.c: inline array aref with integer

internal.h: define inlinable rb_ary_entry_internal.

array.c: use rb_ary_entry_internal.

* Benchmark
ruby --jit mame/optcarrot/bin/optcarrot --benchmark mame/optcarrot/examples/Lan_Master.nes

** Before

checksum: 59662
fps: 58.095175012159686

** After

fps: 59.874751599221526
checksum: 59662

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@62388 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

array.c

@@ -1209,17 +1209,7 @@ rb_ary_elt(VALUE ary, long offset)
 VALUE
 rb_ary_entry(VALUE ary, long offset)
 {
-    long len = RARRAY_LEN(ary);
+    return rb_ary_entry_internal(ary, offset);
-    const VALUE *ptr = RARRAY_CONST_PTR(ary);
-    if (len == 0) return Qnil;
-    if (offset < 0) {
-        offset += len;
-        if (offset < 0) return Qnil;
-    }
-    else if (len <= offset) {
-        return Qnil;
-    }
-    return ptr[offset];
 }
 
 VALUE

internal.h

@@ -1093,6 +1093,22 @@ VALUE rb_check_to_array(VALUE ary);
     })
 #endif
 
+static inline VALUE
+rb_ary_entry_internal(VALUE ary, long offset)
+{
+    long len = RARRAY_LEN(ary);
+    const VALUE *ptr = RARRAY_CONST_PTR(ary);
+    if (len == 0) return Qnil;
+    if (offset < 0) {
+        offset += len;
+        if (offset < 0) return Qnil;
+    }
+    else if (len <= offset) {
+        return Qnil;
+    }
+    return ptr[offset];
+}
+
 /* bignum.c */
 extern const char ruby_digitmap[];
 double rb_big_fdiv_double(VALUE x, VALUE y);

vm_insnhelper.c

@@ -3647,8 +3647,13 @@ vm_opt_aref(VALUE recv, VALUE obj)
     }
     else if (RBASIC_CLASS(recv) == rb_cArray &&
 	     BASIC_OP_UNREDEFINED_P(BOP_AREF, ARRAY_REDEFINED_OP_FLAG)) {
+        if (FIXNUM_P(obj)) {
+            return rb_ary_entry_internal(recv, FIX2LONG(obj));
+        }
+        else {
             return rb_ary_aref1(recv, obj);
         }
+    }
     else if (RBASIC_CLASS(recv) == rb_cHash &&
 	     BASIC_OP_UNREDEFINED_P(BOP_AREF, HASH_REDEFINED_OP_FLAG)) {
 	return rb_hash_aref(recv, obj);