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

record conflicts in a special HLRAction type

Browse source
This commit is contained in:
Sven M. Hallberg 2013-06-19 17:01:13 +02:00
parent 168760b10a
commit 54ba62bfb7
4 changed files with 56 additions and 15 deletions
Download patch file Download diff file Expand all files Collapse all files

21
src/backends/lr.c
View file

@ -159,6 +159,25 @@ HLRAction *h_reduce_action(HArena *arena, const HLRItem *item)
return action;
}
// adds 'new' to the branches of 'action'
// returns a 'action' if it is already of type HLR_CONFLICT
// allocates a new HLRAction otherwise
HLRAction *h_lr_conflict(HArena *arena, HLRAction *action, HLRAction *new)
{
if(action->type != HLR_CONFLICT) {
HLRAction *old = action;
action = h_arena_malloc(arena, sizeof(HLRAction));
action->type = HLR_CONFLICT;
action->branches = h_slist_new(arena);
h_slist_push(action->branches, old);
}
assert(action->type == HLR_CONFLICT);
h_slist_push(action->branches, new);
return action;
}
/* LR driver */
@ -239,6 +258,8 @@ bool h_lrengine_step(HLREngine *engine, const HLRAction *action)
if(action == NULL)
return false; // no handle recognizable in input, terminate
assert(action->type == HLR_SHIFT || action->type == HLR_REDUCE);
if(action->type == HLR_SHIFT) {
h_slist_push(left, (void *)(uintptr_t)engine->state);
h_slist_pop(right); // symbol (discard)