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

make h_lrengine_step a void function again

Browse source
This commit is contained in:
Sven M. Hallberg 2013-06-21 18:46:16 +02:00
parent bf3e3c162e
commit ec88580b22
4 changed files with 65 additions and 40 deletions
Download patch file Download diff file Expand all files Collapse all files

51
src/backends/glr.c
View file

@ -61,6 +61,20 @@ HParseResult *h_glr_parse(HAllocator* mm__, const HParser* parser, HInputStream*
for(HSlistNode **x = &engines->head; *x; ) {
HLREngine *engine = (*x)->elem;
// check for terminated engines
if(engine->run) {
x = &(*x)->next; // advance x with no change
} else {
*x = (*x)->next; // advance x, removing the current element
// check for parse success
HParseResult *res = h_lrengine_result(engine);
if(res)
result = res;
continue;
}
const HLRAction *action = h_lrengine_action(engine, stream);
// fork engine on conflicts
@ -79,28 +93,13 @@ HParseResult *h_glr_parse(HAllocator* mm__, const HParser* parser, HInputStream*
HLRAction *act = x->elem;
HLREngine *eng = fork_engine(engine);
// perform one step; add engine to list if it wants to keep running
bool run = h_lrengine_step(eng, act);
if(run) {
h_slist_push(engines, eng);
} else {
HParseResult *res = h_lrengine_result(eng);
if(res)
result = res;
}
// perform one step and add to list
h_lrengine_step(eng, act);
h_slist_push(engines, eng);
}
}
bool running = h_lrengine_step(engine, action);
if(running) {
x = &(*x)->next; // go to next
} else {
*x = (*x)->next; // remove from list
HParseResult *res = h_lrengine_result(engine);
if(res)
result = res;
}
h_lrengine_step(engine, action);
}
}
@ -120,6 +119,20 @@ HParserBackendVTable h__glr_backend_vtable = {
// XXX TODO
// - eliminate right stack by always doing a shift after reduce
// (shift should always follow reduce because rightmost)
// - split tables into
// - one mapping input bytes to actions (shift or reduce or conflict)
// - one mapping reduced-to lhs nonterminals to shift states
// - can there still be conflicts here?
// - use HStringMap to represent lookahead sets and the "piggyback" table
// - implement engine merging
// - triggered when two enter the same state
// - old stacks (/engines?) saved
// - new common suffix stack created
// - when rewinding (during reduce), watch for empty stack -> demerge
// dummy!
int test_glr(void)