[PATCH v2] Use ^=1 to toggle between 0 and 1

From: Seija Kijin <doremylover123@gmail.com>

If it is known that an int is either 1 or 0, doing an exclusive or to switch instead of a modulus makes more sense and is more efficient.

Signed-off-by: Seija <doremylover123@gmail.com>
---
    Use ^=1 to toggle between 0 and 1
    
    If it is known that an int is either 1 or 0, doing an exclusive or to
    switch instead of a modulus makes more sense and is more efficient.
    
    Signed-off-by: Seija Kijin doremylover123@gmail.com

Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-1620%2FAreaZR%2Fbuffer-v2
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-1620/AreaZR/buffer-v2
Pull-Request: https://github.com/git/git/pull/1620

Range-diff vs v1:

 1:  1bdc62e1b19 ! 1:  5819a51526b Use ^=1 to toggle between 0 and 1
     @@ Commit message
          doing an exclusive or to switch instead of a
          modulus makes more sense and is more efficient.
      
     -    Signed-off-by: Seija Kijin doremylover123@gmail.com
     -
     - ## builtin/fast-export.c ##
     -@@ builtin/fast-export.c: static void anonymize_ident_line(const char **beg, const char **end)
     - 	struct ident_split split;
     - 	const char *end_of_header;
     - 
     --	out = &buffers[which_buffer++];
     --	which_buffer %= ARRAY_SIZE(buffers);
     -+	out = &buffers[which_buffer];
     -+	which_buffer ^= 1;
     - 	strbuf_reset(out);
     - 
     - 	/* skip "committer", "author", "tagger", etc */
     +    Signed-off-by: Seija <doremylover123@gmail.com>
      
       ## diff.c ##
      @@ diff.c: static void mark_color_as_moved(struct diff_options *o,
     @@ diff.c: static void mark_color_as_moved(struct diff_options *o,
       				flipped_block = 0;
       
      
     - ## ident.c ##
     -@@ ident.c: const char *fmt_ident(const char *name, const char *email,
     - 	int want_name = !(flag & IDENT_NO_NAME);
     - 
     - 	struct strbuf *ident = &ident_pool[index];
     --	index = (index + 1) % ARRAY_SIZE(ident_pool);
     -+	index ^= 1;
     - 
     - 	if (!email) {
     - 		if (whose_ident == WANT_AUTHOR_IDENT && git_author_email.len)
     -
       ## t/helper/test-path-utils.c ##
      @@ t/helper/test-path-utils.c: static int check_dotfile(const char *x, const char **argv,
       	int res = 0, expect = 1;

 diff.c                     | 2 +-
 t/helper/test-path-utils.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)