(CHAR_STRING): Optimized for single byte characters.

1 files changed, 5 insertions, 3 deletions

diff --git a/src/charset.h b/src/charset.h
index 83b31abf1f6..b8ee0af40f7 100644
--- a/src/charset.h
+++ b/src/charset.h
@@ -524,9 +524,11 @@ extern int iso_charset_table[2][2][128];
    advance.  Returns the length of the multi-byte form.  If C is an
    invalid character code, signal an error.  */
 
-#define CHAR_STRING(c, str)             \
-  (ASCII_BYTE_P (c)                     \
-   ? (*(str) = (unsigned char)(c), 1)   \
+#define CHAR_STRING(c, str)                                               \
+  (SINGLE_BYTE_CHAR_P (c)                                                 \
+   ? ((ASCII_BYTE_P (c) || c >= 0xA0)                                     \
+      ? (*(str) = (unsigned char)(c), 1)                                  \
+      : (*(str) = LEADING_CODE_8_BIT_CONTROL, *((str)+ 1) = c + 0x20, 2)) \
    : char_to_string (c, (unsigned char *) str))
 
 /* Return a character code of the character of which multi-byte form