Refactor converting number to string by using optimized function (#886)

ohler55 · Jun 16, 2023 · 4bfb4b5 · 4bfb4b5
1 parent c86e60d
commit 4bfb4b5
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Showing 5 changed files with 37 additions and 44 deletions.
diff --git a/ext/oj/code.c b/ext/oj/code.c
@@ -185,24 +185,17 @@ void oj_code_attrs(VALUE obj, Attr attrs, int depth, Out out, bool with_class) {
             } else {
                 char   buf[32];
                 char  *b   = buf + sizeof(buf) - 1;
-                int    neg = 0;
+                bool   neg = false;
                 long   num = attrs->num;
                 size_t cnt = 0;
 
                 if (0 > num) {
-                    neg = 1;
+                    neg = true;
                     num = -num;
                 }
                 *b-- = '\0';
                 if (0 < num) {
-                    for (; 0 < num; num /= 10, b--) {
-                        *b = (num % 10) + '0';
-                    }
-                    if (neg) {
-                        *b = '-';
-                    } else {
-                        b++;
-                    }
+                    b = oj_longlong_to_string(num, neg, b);
                 } else {
                     *b = '0';
                 }

diff --git a/ext/oj/dump.c b/ext/oj/dump.c
@@ -1010,11 +1010,33 @@ static const char digits_table[] = "\
 80818283848586878889\
 90919293949596979899";
 
+char *oj_longlong_to_string(long long num, bool negative, char *buf) {
+    while (100 <= num) {
+        unsigned idx = num % 100 * 2;
+        *buf--       = digits_table[idx + 1];
+        *buf--       = digits_table[idx];
+        num /= 100;
+    }
+    if (num < 10) {
+        *buf-- = num + '0';
+    } else {
+        *buf-- = digits_table[num * 2 + 1];
+        *buf-- = digits_table[num * 2];
+    }
+
+    if (negative) {
+        *buf = '-';
+    } else {
+        buf++;
+    }
+    return buf;
+}
+
 void oj_dump_fixnum(VALUE obj, int depth, Out out, bool as_ok) {
     char      buf[32];
     char     *b              = buf + sizeof(buf) - 1;
     long long num            = NUM2LL(obj);
-    int       neg            = 0;
+    bool      neg            = false;
     size_t    cnt            = 0;
     bool      dump_as_string = false;
 
@@ -1023,7 +1045,7 @@ void oj_dump_fixnum(VALUE obj, int depth, Out out, bool as_ok) {
         dump_as_string = true;
     }
     if (0 > num) {
-        neg = 1;
+        neg = true;
         num = -num;
     }
     *b-- = '\0';
@@ -1032,24 +1054,7 @@ void oj_dump_fixnum(VALUE obj, int depth, Out out, bool as_ok) {
         *b-- = '"';
     }
     if (0 < num) {
-        while (100 <= num) {
-            unsigned idx = num % 100 * 2;
-            *b--         = digits_table[idx + 1];
-            *b--         = digits_table[idx];
-            num /= 100;
-        }
-        if (num < 10) {
-            *b-- = num + '0';
-        } else {
-            *b-- = digits_table[num * 2 + 1];
-            *b-- = digits_table[num * 2];
-        }
-
-        if (neg) {
-            *b = '-';
-        } else {
-            b++;
-        }
+        b = oj_longlong_to_string(num, neg, b);
     } else {
         *b = '0';
     }

diff --git a/ext/oj/dump.h b/ext/oj/dump.h
@@ -93,10 +93,7 @@ inline static void dump_ulong(unsigned long num, Out out) {
 
     *b-- = '\0';
     if (0 < num) {
-        for (; 0 < num; num /= 10, b--) {
-            *b = (num % 10) + '0';
-        }
-        b++;
+        b = oj_longlong_to_string((long long)num, false, b);
     } else {
         *b = '0';
     }

diff --git a/ext/oj/fast.c b/ext/oj/fast.c
@@ -114,10 +114,7 @@ inline static char *ulong_fill(char *s, size_t num) {
     char *b = buf + sizeof(buf) - 1;
 
     *b-- = '\0';
-    for (; 0 < num; num /= 10, b--) {
-        *b = (num % 10) + '0';
-    }
-    b++;
+    b    = oj_longlong_to_string((long long)num, false, b);
     if ('\0' == *b) {
         b--;
         *b = '0';

diff --git a/ext/oj/oj.h b/ext/oj/oj.h
@@ -262,12 +262,13 @@ extern VALUE oj_custom_parse_cstr(int argc, VALUE *argv, char *json, size_t len)
 extern bool oj_hash_has_key(VALUE hash, VALUE key);
 extern void oj_parse_options(VALUE ropts, Options copts);
 
-extern void oj_dump_obj_to_json(VALUE obj, Options copts, Out out);
-extern void oj_dump_obj_to_json_using_params(VALUE obj, Options copts, Out out, int argc, VALUE *argv);
-extern void oj_write_obj_to_file(VALUE obj, const char *path, Options copts);
-extern void oj_write_obj_to_stream(VALUE obj, VALUE stream, Options copts);
-extern void oj_dump_leaf_to_json(Leaf leaf, Options copts, Out out);
-extern void oj_write_leaf_to_file(Leaf leaf, const char *path, Options copts);
+extern void  oj_dump_obj_to_json(VALUE obj, Options copts, Out out);
+extern void  oj_dump_obj_to_json_using_params(VALUE obj, Options copts, Out out, int argc, VALUE *argv);
+extern void  oj_write_obj_to_file(VALUE obj, const char *path, Options copts);
+extern void  oj_write_obj_to_stream(VALUE obj, VALUE stream, Options copts);
+extern void  oj_dump_leaf_to_json(Leaf leaf, Options copts, Out out);
+extern void  oj_write_leaf_to_file(Leaf leaf, const char *path, Options copts);
+extern char *oj_longlong_to_string(long long num, bool negative, char *buf);
 
 extern void oj_str_writer_push_key(StrWriter sw, const char *key);
 extern void oj_str_writer_push_object(StrWriter sw, const char *key);