This repository has been archived on 2023-08-20. You can view files and clone it, but cannot push or open issues or pull requests.
yap-6.3/OPTYap/or.sba_engine.c

338 lines
10 KiB
C

/************************************************************************
** **
** The YapTab/YapOr/OPTYap systems **
** **
** YapTab extends the Yap Prolog engine to support sequential tabling **
** YapOr extends the Yap Prolog engine to support or-parallelism **
** OPTYap extends the Yap Prolog engine to support or-parallel tabling **
** **
** **
** Yap Prolog was developed at University of Porto, Portugal **
** **
************************************************************************/
/* ------------------ **
** Includes **
** ------------------ */
#include "Yap.h"
#ifdef YAPOR_SBA
#include <stdio.h>
#include "Yatom.h"
#include "YapHeap.h"
#include "or.macros.h"
#include "opt.mavar.h"
/* ------------------------------------- **
** Local functions declaration **
** ------------------------------------- */
static void share_private_nodes(int worker_q);
static void
reset_trail(tr_fr_ptr tr_top, tr_fr_ptr trp)
{
register CELL aux_cell;
/* unbinding variables */
while (tr_top != trp) {
aux_cell = TrailTerm(--trp);
/* check for global or local variables */
if (IsVarTerm(aux_cell)) {
/* clean up the trail when we backtrack */
/* shouldn't this test always succeed? */
if (Unsigned((Int)(aux_cell)-(Int)(H_FZ)) >
Unsigned((Int)(B_FZ)-(Int)(H_FZ))) {
RESET_VARIABLE(STACK_TO_SBA(aux_cell));
} else {
RESET_VARIABLE(aux_cell);
}
}
else if (IsPairTerm(aux_cell)) {
/* avoid frozen segments */
if ((ADDR) RepPair(aux_cell) > HeapTop) {
trp = (tr_fr_ptr) RepPair(aux_cell);
}
#ifdef MULTI_ASSIGNMENT_VARIABLES
} else {
CELL *aux_ptr = RepAppl(aux_cell);
trp--;
if (Unsigned((Int)(aux_ptr)-(Int)(H_FZ)) >
Unsigned((Int)(B_FZ)-(Int)(H_FZ))) {
*STACK_TO_SBA(aux_ptr) = TrailTerm(trp);
} else {
*aux_ptr = TrailTerm(trp);
}
#endif /* MULTI_ASSIGNMENT_VARIABLES */
}
}
}
/* ---------------------- **
** Local macros **
** ---------------------- */
#define COMPUTE_SEGMENTS_TO_COPY_TO(Q) \
REMOTE_end_local_copy(Q) = (CELL) (REMOTE_top_cp(Q)); \
REMOTE_start_local_copy(Q) = (CELL) (B)
/* -------------------------- **
** Global functions **
** -------------------------- */
void make_root_choice_point(void) {
if (worker_id == 0) {
LOCAL_top_cp = GLOBAL_root_cp = OrFr_node(GLOBAL_root_or_fr) = B;
B->cp_h = H0;
B->cp_ap = GETWORK;
B->cp_or_fr = GLOBAL_root_or_fr;
} else {
B = LOCAL_top_cp = GLOBAL_root_cp;
TR = B->cp_tr;
}
LOCAL_top_or_fr = GLOBAL_root_or_fr;
LOCAL_load = 0;
LOCAL_prune_request = NULL;
BRANCH(worker_id, 0) = 0;
H_FZ = (CELL *) LOCAL_GlobalBase;
B_FZ = (choiceptr) LOCAL_LocalBase;
TR_FZ = (tr_fr_ptr) LOCAL_TrailBase;
}
void free_root_choice_point(void) {
reset_trail(LOCAL_top_cp->cp_tr, TR);
TR = LOCAL_top_cp->cp_tr;
B = LOCAL_top_cp->cp_b;
LOCAL_top_cp = (choiceptr) LOCAL_LocalBase;
H_FZ = (CELL *) LOCAL_GlobalBase;
B_FZ = (choiceptr) LOCAL_LocalBase;
TR_FZ = (tr_fr_ptr) LOCAL_TrailBase;
}
void p_share_work(void) {
int worker_q = LOCAL_share_request;
if (! BITMAP_member(OrFr_members(REMOTE_top_or_fr(worker_q)), worker_id) ||
B == REMOTE_top_cp(worker_q) ||
(LOCAL_load <= GLOBAL_delayed_release_load && OrFr_nearest_livenode(LOCAL_top_or_fr) == NULL)) {
/* refuse sharing request */
REMOTE_reply_signal(LOCAL_share_request) = no_sharing;
LOCAL_share_request = MAX_WORKERS;
PUT_OUT_REQUESTABLE(worker_id);
return;
}
/* sharing request accepted */
/* LOCAL_reply_signal = sharing; */
COMPUTE_SEGMENTS_TO_COPY_TO(worker_q);
share_private_nodes(worker_q);
REMOTE_reply_signal(worker_q) = sharing;
/* REMOTE_reply_signal(worker_q) = nodes_shared; */
/* while (LOCAL_reply_signal == sharing); */
LOCAL_share_request = MAX_WORKERS;
PUT_IN_REQUESTABLE(worker_id);
return;
}
int q_share_work(int worker_p) {
register tr_fr_ptr aux_tr;
register CELL aux_cell;
LOCK_OR_FRAME(LOCAL_top_or_fr);
if (Get_REMOTE_prune_request(worker_p)) {
/* worker p with prune request */
UNLOCK_OR_FRAME(LOCAL_top_or_fr);
return FALSE;
}
YAPOR_ERROR_CHECKING(q_share_work, OrFr_pend_prune_cp(LOCAL_top_or_fr) && BRANCH_LTT(worker_p, OrFr_depth(LOCAL_top_or_fr)) < OrFr_pend_prune_ltt(LOCAL_top_or_fr));
/* there is no pending prune with worker p at right --> safe move to worker p branch */
BRANCH(worker_id, OrFr_depth(LOCAL_top_or_fr)) = BRANCH(worker_p, OrFr_depth(LOCAL_top_or_fr));
LOCAL_prune_request = NULL;
UNLOCK_OR_FRAME(LOCAL_top_or_fr);
reset_trail(LOCAL_top_cp->cp_tr, TR);
TR = LOCAL_top_cp->cp_tr;
/* make sharing request */
LOCK_WORKER(worker_p);
if (BITMAP_member(GLOBAL_bm_idle_workers, worker_p) ||
REMOTE_share_request(worker_p) != MAX_WORKERS) {
/* worker p is idle or has another request */
UNLOCK_WORKER(worker_p);
return FALSE;
}
REMOTE_share_request(worker_p) = worker_id;
UNLOCK_WORKER(worker_p);
/* wait for an answer */
while (LOCAL_reply_signal == worker_ready);
if (LOCAL_reply_signal == no_sharing) {
/* sharing request refused */
LOCAL_reply_signal = worker_ready;
return FALSE;
}
/* install fase --> TR and LOCAL_top_cp->cp_tr are equal */
TR = ((choiceptr)LOCAL_end_local_copy)->cp_tr;
aux_tr = ((choiceptr) LOCAL_start_local_copy)->cp_tr;
NEW_MAHASH((ma_h_inner_struct *)H);
while (TR != aux_tr) {
aux_cell = TrailTerm(--aux_tr);
if (IsVarTerm(aux_cell)) {
CELL *ptr = STACK_TO_SBA(aux_cell);
*ptr = TrailVal(aux_tr);
} else if ((ADDR) RepPair(aux_cell) >= HeapTop) {
/* avoid frozen segments */
aux_tr = (tr_fr_ptr) RepPair(aux_cell);
#ifdef MULTI_ASSIGNMENT_VARIABLES
} else if (IsApplTerm(aux_cell)) {
CELL *cell_ptr = RepAppl(aux_cell);
if (!lookup_ma_var(cell_ptr)) {
/* first time we found the variable, let's put the new value */
CELL *ptr = STACK_TO_SBA(cell_ptr);
*ptr = TrailVal(aux_tr);
}
/* skip the old value */
aux_tr--;
}
#endif /* MULTI_ASSIGNMENT_VARIABLES */
}
/* update registers and return */
/* REMOTE_reply_signal(worker_p) = worker_ready; */
LOCAL_reply_signal = worker_ready;
PUT_IN_REQUESTABLE(worker_id);
TR = LOCAL_top_cp->cp_tr;
return TRUE;
}
/* ------------------------- **
** Local functions **
** ------------------------- */
static
void share_private_nodes(int worker_q) {
int depth;
choiceptr AuxB;
or_fr_ptr or_frame, previous_or_frame;
/* initialize auxiliary variables */
AuxB = B;
previous_or_frame = NULL;
depth = OrFr_depth(LOCAL_top_or_fr);
/* sharing loop */
while (AuxB != LOCAL_top_cp) {
depth++;
ALLOC_OR_FRAME(or_frame);
INIT_LOCK(OrFr_lock(or_frame));
OrFr_node(or_frame) = AuxB;
OrFr_alternative(or_frame) = AuxB->cp_ap;
OrFr_pend_prune_cp(or_frame) = NULL;
OrFr_nearest_leftnode(or_frame) = LOCAL_top_or_fr;
OrFr_qg_solutions(or_frame) = NULL;
BITMAP_clear(OrFr_members(or_frame));
BITMAP_insert(OrFr_members(or_frame), worker_id);
BITMAP_insert(OrFr_members(or_frame), worker_q);
if (AuxB->cp_ap && YAMOP_SEQ(AuxB->cp_ap)) {
AuxB->cp_ap = GETWORK_SEQ;
} else {
AuxB->cp_ap = GETWORK;
}
AuxB->cp_or_fr = or_frame;
AuxB = AuxB->cp_b;
if (previous_or_frame) {
OrFr_nearest_livenode(previous_or_frame) = OrFr_next(previous_or_frame) = or_frame;
}
previous_or_frame = or_frame;
}
/* initialize last or-frame pointer */
or_frame = AuxB->cp_or_fr;
if (previous_or_frame) {
OrFr_nearest_livenode(previous_or_frame) = OrFr_next(previous_or_frame) = or_frame;
}
/* update depth */
if (depth >= MAX_BRANCH_DEPTH)
Yap_Error(INTERNAL_ERROR, TermNil, "maximum depth exceded (share_private_nodes)");
or_frame = B->cp_or_fr;
while (or_frame != LOCAL_top_or_fr) {
unsigned int branch;
if (OrFr_alternative(or_frame)) {
branch = YAMOP_OR_ARG(OrFr_alternative(or_frame)) + 1;
} else {
branch = 1;
}
branch |= YAMOP_CUT_FLAG; /* in doubt, assume cut */
BRANCH(worker_id, depth) = BRANCH(worker_q, depth) = branch;
OrFr_depth(or_frame) = depth--;
or_frame = OrFr_next_on_stack(or_frame);
}
/* update old shared nodes */
while (or_frame != REMOTE_top_or_fr(worker_q)) {
LOCK_OR_FRAME(or_frame);
BRANCH(worker_q, OrFr_depth(or_frame)) = BRANCH(worker_id, OrFr_depth(or_frame));
BITMAP_insert(OrFr_members(or_frame), worker_q);
UNLOCK_OR_FRAME(or_frame);
or_frame = OrFr_next_on_stack(or_frame);
}
/* move conditional bindings to BA */
{
tr_fr_ptr top, tr_ptr;
top = LOCAL_top_cp->cp_tr;
tr_ptr = TR;
while (tr_ptr != top) {
CELL aux_cell = TrailTerm(--tr_ptr);
if (IsVarTerm(aux_cell) &&
((CELL *)aux_cell < B->cp_h || (choiceptr)aux_cell > B) &&
!((CELL *)aux_cell < H_FZ || (choiceptr)aux_cell > B_FZ)) {
CELL *ptr = STACK_TO_SBA(aux_cell);
*ptr = TrailVal(tr_ptr);
*(CELL *)aux_cell = (CELL)ptr;
} else if (IsPairTerm(aux_cell) && (ADDR) RepPair(aux_cell) > HeapTop) {
/* avoid frozen segments */
aux_cell = (CELL) RepPair(aux_cell);
tr_ptr = (tr_fr_ptr) aux_cell;
#ifdef MULTI_ASSIGNMENT_VARIABLES
} else {
CELL *cell_ptr = RepAppl(aux_cell);
/* first do as a for a standard cell */
if ((cell_ptr < B->cp_h || cell_ptr > (CELL *)B) && !(cell_ptr < H_FZ || (choiceptr)cell_ptr > B_FZ)) {
CELL *ptr = STACK_TO_SBA(cell_ptr);
/* we may have several bindings in the trail */
if ((CELL)ptr != *cell_ptr) {
*ptr = TrailVal(tr_ptr);
*cell_ptr = (CELL)ptr;
}
}
/* but we also need to skip the old value */
tr_ptr--;
#endif /* MULTI_ASSIGNMENT_VARIABLES */
}
}
}
/* update frozen registers */
B_FZ = B;
H_FZ = B->cp_h;
TR_FZ = B->cp_tr;
/* update top shared nodes */
REMOTE_top_cp(worker_q) = LOCAL_top_cp = B;
REMOTE_top_or_fr(worker_q) = LOCAL_top_or_fr = LOCAL_top_cp->cp_or_fr;
/* update prune request */
if (LOCAL_prune_request) {
CUT_send_prune_request(worker_q, LOCAL_prune_request);
}
/* update load and return */
REMOTE_load(worker_q) = LOCAL_load = 0;
}
#endif /* SBA */