Stop prebuilding object_delim2

Also, remove static functions that are no longer used.

This speeds up `JSON.generate` by about 5% in a benchmark.

Author: mame

ext/json/ext/fbuffer/fbuffer.h

@@ -55,14 +55,15 @@ typedef struct FBufferStruct {
 
 static FBuffer *fbuffer_alloc(unsigned long initial_length);
 static void fbuffer_free(FBuffer *fb);
+#ifndef JSON_GENERATOR
 static void fbuffer_clear(FBuffer *fb);
+#endif
 static void fbuffer_append(FBuffer *fb, const char *newstr, unsigned long len);
 #ifdef JSON_GENERATOR
 static void fbuffer_append_long(FBuffer *fb, long number);
 #endif
 static void fbuffer_append_char(FBuffer *fb, char newchr);
 #ifdef JSON_GENERATOR
-static FBuffer *fbuffer_dup(FBuffer *fb);
 static VALUE fbuffer_to_s(FBuffer *fb);
 #endif
 
@@ -86,10 +87,12 @@ static void fbuffer_free(FBuffer *fb)
     ruby_xfree(fb);
 }
 
+#ifndef JSON_GENERATOR
 static void fbuffer_clear(FBuffer *fb)
 {
     fb->len = 0;
 }
+#endif
 
 static inline void fbuffer_inc_capa(FBuffer *fb, unsigned long requested)
 {
@@ -168,16 +171,6 @@ static void fbuffer_append_long(FBuffer *fb, long number)
     fbuffer_append(fb, buf, len);
 }
 
-static FBuffer *fbuffer_dup(FBuffer *fb)
-{
-    unsigned long len = fb->len;
-    FBuffer *result;
-
-    result = fbuffer_alloc(len);
-    fbuffer_append(result, FBUFFER_PAIR(fb));
-    return result;
-}
-
 static VALUE fbuffer_to_s(FBuffer *fb)
 {
     VALUE result = rb_str_new(FBUFFER_PTR(fb), FBUFFER_LEN(fb));

ext/json/ext/generator/generator.c

@@ -421,7 +421,6 @@ static void State_free(void *ptr)
     if (state->space_before) ruby_xfree(state->space_before);
     if (state->object_nl) ruby_xfree(state->object_nl);
     if (state->array_nl) ruby_xfree(state->array_nl);
-    if (state->object_delim2) fbuffer_free(state->object_delim2);
     ruby_xfree(state);
 }
 
@@ -434,7 +433,6 @@ static size_t State_memsize(const void *ptr)
     if (state->space_before) size += state->space_before_len + 1;
     if (state->object_nl) size += state->object_nl_len + 1;
     if (state->array_nl) size += state->array_nl_len + 1;
-    if (state->object_delim2) size += FBUFFER_CAPA(state->object_delim2);
     return size;
 }
 
@@ -648,8 +646,6 @@ json_object_i(VALUE key, VALUE val, VALUE _arg)
     long object_nl_len = state->object_nl_len;
     char *indent = state->indent;
     long indent_len = state->indent_len;
-    char *delim2 = FBUFFER_PTR(state->object_delim2);
-    long delim2_len = FBUFFER_LEN(state->object_delim2);
     long depth = state->depth;
     int j;
 
@@ -677,7 +673,9 @@ json_object_i(VALUE key, VALUE val, VALUE _arg)
     }
 
     generate_json_string(buffer, Vstate, state, key_to_s);
-    fbuffer_append(buffer, delim2, delim2_len);
+    if (RB_UNLIKELY(state->space_before)) fbuffer_append(buffer, state->space_before, state->space_before_len);
+    fbuffer_append_char(buffer, ':');
+    if (RB_UNLIKELY(state->space)) fbuffer_append(buffer, state->space, state->space_len);
     generate_json(buffer, Vstate, state, val);
 
     arg->iter++;
@@ -885,15 +883,6 @@ static FBuffer *cState_prepare_buffer(VALUE self)
     GET_STATE(self);
     buffer = fbuffer_alloc(state->buffer_initial_length);
 
-    if (state->object_delim2) {
-        fbuffer_clear(state->object_delim2);
-    } else {
-        state->object_delim2 = fbuffer_alloc(16);
-    }
-    if (state->space_before) fbuffer_append(state->object_delim2, state->space_before, state->space_before_len);
-    fbuffer_append_char(state->object_delim2, ':');
-    if (state->space) fbuffer_append(state->object_delim2, state->space, state->space_len);
-
     return buffer;
 }
 
@@ -1006,7 +995,6 @@ static VALUE cState_init_copy(VALUE obj, VALUE orig)
     objState->space_before = fstrndup(origState->space_before, origState->space_before_len);
     objState->object_nl = fstrndup(origState->object_nl, origState->object_nl_len);
     objState->array_nl = fstrndup(origState->array_nl, origState->array_nl_len);
-    if (origState->object_delim2) objState->object_delim2 = fbuffer_dup(origState->object_delim2);
     return obj;
 }
 

ext/json/ext/generator/generator.h

@@ -55,7 +55,6 @@ typedef struct JSON_Generator_StateStruct {
     long object_nl_len;
     char *array_nl;
     long array_nl_len;
-    FBuffer *object_delim2;
     long max_nesting;
     char allow_nan;
     char ascii_only;