emileclarkb/hammer
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

represent input tokens in a way that doesn't clash with NULL

Browse source
This commit is contained in:
Sven M. Hallberg 2013-05-07 18:47:32 +02:00
parent e504c6fc36
commit 16f933013a
1 changed files with 15 additions and 11 deletions
Download patch file Download diff file Expand all files Collapse all files

26
src/backends/ll.c
View file

@ -17,8 +17,13 @@ typedef struct HCFGrammar_ {
HArena *arena;
} HCFGrammar;
typedef int HCFTerminal;
static HCFTerminal end_token = -1;
// mapping input bytes or end to tokens
// we want to use these, cast to void *, as elements in hashsets
// therefore we must avoid 0 as a token value because NULL means "not in set".
typedef uintptr_t HCFToken;
static inline HCFToken char_token(char c) { return (0x100 | c); }
static inline char token_char(HCFToken t) { return (0xFF & t); }
static HCFToken end_token = 0x200;
bool h_eq_ptr(const void *p, const void *q) { return (p==q); }
HHashValue h_hash_ptr(const void *p) { return (uintptr_t)p; }
@ -210,16 +215,16 @@ HHashSet *h_first_symbol(HCFGrammar *g, const HCFChoice *x)
switch(x->type) {
case HCF_END:
h_hashset_put(ret, (void *)(intptr_t)end_token);
h_hashset_put(ret, (void *)end_token);
break;
case HCF_CHAR:
h_hashset_put(ret, (void *)(intptr_t)x->chr);
h_hashset_put(ret, (void *)char_token(x->chr));
break;
case HCF_CHARSET:
c=0;
do {
if(charset_isset(x->charset, c))
h_hashset_put(ret, (void *)(intptr_t)c);
h_hashset_put(ret, (void *)char_token(c));
} while(c++ < 255);
break;
case HCF_CHOICE:
@ -532,15 +537,14 @@ void h_pprint_tokenset(FILE *file, const HCFGrammar *g, const HHashSet *set, int
for(hte = &set->contents[i]; hte; hte = hte->next) {
if(hte->key == NULL)
continue;
HCFTerminal a = (intptr_t)hte->key;
// BUG this ignores tokens with value 0!
HCFToken a = (HCFToken)hte->key;
if(a == '$')
fputs("\\$", file);
else if(a == end_token)
if(a == end_token)
fputc('$', file);
else if(token_char(a) == '$')
fputs("\\$", file);
else
pprint_char(file, a);
pprint_char(file, token_char(a));
}
}