hush: ~5% faster parsing of typical shell scripts

0-9,A-Z,a-z are never special and just go into the current word.

function                                             old     new   delta
parse_stream                                        2476    2565     +89

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 19 insertions, 13 deletions

diff --git a/shell/hush.c b/shell/hush.c
index 10ade0b9e..ecdb5eea9 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -2743,7 +2743,7 @@ static const char *setup_prompt_string(void)
         debug_printf("prompt_str '%s'\n", prompt_str);
         return prompt_str;
 }
-static int get_user_input(struct in_str *i)
+static int get_interactive_input(struct in_str *i)
 {
 # if ENABLE_FEATURE_EDITING
         /* In EDITING case, this function reads next input line,
@@ -2853,7 +2853,7 @@ static int fgetc_interactive(struct in_str *i)
         /* If it's interactive stdin, get new line. */
         if (G_interactive_fd && i->file == G.HFILE_stdin) {
                 /* Returns first char (or EOF), the rest is in i->p[] */
-                ch = get_user_input(i);
+                ch = get_interactive_input(i);
                 G.promptmode = 1; /* PS2 */
                 debug_printf_prompt("%s promptmode=%d\n", __func__, G.promptmode);
         } else {
@@ -2880,14 +2880,7 @@ static int i_getch(struct in_str *i)
                 ch = (unsigned char)*i->p;
                 if (ch != '\0') {
                         i->p++;
-                        i->last_char = ch;
-#if ENABLE_HUSH_LINENO_VAR
-                        if (ch == '\n') {
-                                G.parse_lineno++;
-                                debug_printf_parse("G.parse_lineno++ = %u\n", G.parse_lineno);
-                        }
-#endif
-                        return ch;
+                        goto out1;
                 }
                 return EOF;
         }
@@ -2915,13 +2908,14 @@ static int i_getch(struct in_str *i)
         ch = fgetc_interactive(i);
  out:
         debug_printf("file_get: got '%c' %d\n", ch, ch);
-        i->last_char = ch;
+ out1:
 #if ENABLE_HUSH_LINENO_VAR
         if (ch == '\n') {
                 G.parse_lineno++;
                 debug_printf_parse("G.parse_lineno++ = %u\n", G.parse_lineno);
         }
 #endif
+        i->last_char = ch;
         return ch;
 }
 
@@ -3077,7 +3071,7 @@ static void o_grow_by(o_string *o, int len)
         }
 }
 
-static void o_addchr(o_string *o, int ch)
+static ALWAYS_INLINE void INLINED_o_addchr(o_string *o, int ch)
 {
         debug_printf("o_addchr: '%c' o->length=%d o=%p\n", ch, o->length, o);
         if (o->length < o->maxlen) {
@@ -3091,6 +3085,10 @@ static void o_addchr(o_string *o, int ch)
         o_grow_by(o, 1);
         goto add;
 }
+static void o_addchr(o_string *o, int ch)
+{
+        INLINED_o_addchr(o, ch);
+}
 
 #if 0
 /* Valid only if we know o_string is not empty */
@@ -5623,6 +5621,14 @@ static struct pipe *parse_stream(char **pstring,
                 ch = i_getch(input);
                 debug_printf_parse(": ch:%c (%d) globprotect:%d\n",
                                 ch, ch, !!(ctx.word.o_expflags & EXP_FLAG_GLOBPROTECT_CHARS));
+# if ENABLE_HUSH_NEED_FOR_SPEED
+                if (isalnum(ch)) {
+                        /* 0-9A-Za-z are never special and just go into the current word */
+                        /* ~5% faster parsing of typical shell scripts */
+                        INLINED_o_addchr(&ctx.word, ch);
+                        continue;
+                }
+#endif
                 if (ch == EOF)
                         break;
 
@@ -8223,7 +8229,7 @@ static void restore_redirects(struct squirrel *sq)
                  * Redirect moves ->fd to e.g. 10,
                  * and it is not restored above (we do not restore script fds
                  * after redirects, we just use new, "moved" fds).
-                 * However for stdin, get_user_input() -> read_line_input(),
+                 * However for stdin, get_interactive_input() -> read_line_input(),
                  * and read builtin, depend on fd == STDIN_FILENO.
                  */
                 debug_printf_redir("restoring %d to stdin\n", G.HFILE_stdin->fd);