rb_str_concat_literals: use rb_str_buf_append

That's about 1.30x faster.

2 files changed, 11 insertions, 2 deletions

diff --git a/benchmark/string_concat.yml b/benchmark/string_concat.yml
index b8a69ed909..e65c00cca9 100644
--- a/benchmark/string_concat.yml
+++ b/benchmark/string_concat.yml
@@ -33,3 +33,13 @@ benchmark:
     buffer << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK
     buffer << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK
     buffer << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK
+  interpolation: |
+    buffer = "#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}" \
+      "#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}" \
+      "#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}" \
+      "#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}" \
+      "#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}" \
+      "#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}" \
+      "#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}" \
+      "#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}" \
+      "#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}"
diff --git a/string.c b/string.c
index a2bc7410fa..963652cdb9 100644
--- a/string.c
+++ b/string.c
@@ -3393,8 +3393,7 @@ rb_str_concat_literals(size_t num, const VALUE *strary)
         const VALUE v = strary[i];
         int encidx = ENCODING_GET(v);
 
-        rb_enc_cr_str_buf_cat(str, RSTRING_PTR(v), RSTRING_LEN(v),
-                              encidx, ENC_CODERANGE(v), NULL);
+        rb_str_buf_append(str, v);
         if (encidx != ENCINDEX_US_ASCII) {
             if (ENCODING_GET_INLINED(str) == ENCINDEX_US_ASCII)
                 rb_enc_set_index(str, encidx);