diff options
Diffstat (limited to 'src/alf.c')
| -rw-r--r-- | src/alf.c | 22 |
1 files changed, 15 insertions, 7 deletions
@@ -194,15 +194,24 @@ void store_token(int tok) { } } -/* search backwards, the tokens are stored with longer ones later +/* match_token() is a brute-force search, which is why alf is so slow. + I'll do something smarter at some point. + search backwards, the tokens are stored with longer ones later in the list. */ int match_token(int pos) { - int i; + int i, maxlen; + + maxlen = input_len - pos; for(i = curr_token - 1; i >= INIT_TOKEN; i--) { + /* don't search past the end of the input */ + if(tokentab[i].length > maxlen) continue; + /* if the first char doesn't match, don't bother with memcmp. this is a 5x speedup (!) */ if(input_buf[pos] != *(tokentab[i].start)) continue; + + /* memcmp is where alf spends most of its time. */ if(memcmp(&input_buf[pos], tokentab[i].start, tokentab[i].length) == 0) return i; } @@ -213,16 +222,15 @@ int match_token(int pos) { } void make_token(int start, int end) { + /* if the token table is full, reset it. basically start over like + we would with a new file. */ if(curr_token == max_token) { - // printf("%d: curr_token %d == max_token, ", in_pos, curr_token); if(token_bits == MAX_BITS) { - // printf("token_bits %d == MAX_BITS, reset\n", token_bits); store_token(TOK_RESET); /* stored at the *old* token size! */ - token_bits = 9; + token_bits = INITIAL_BITS; init_table(); - return; + return; /* since we're starting over, *don't* make a token */ } else { - // printf("token_bits %d < MAX_BITS, inc\n", token_bits); token_bits++; } max_token = 1 << token_bits; |