make sure we have enough room before we enter a clause.

C/absmi.c

@@ -1675,18 +1675,21 @@ Yap_absmi(int inp)
 *****************************************************************/
 
       /* ensure_space                   */
-      BOp(ensure_space, ip);
+      BOp(ensure_space, Osbpi);
       {
-	Int sz =  PREG->u.ip.i;   
+	Int sz =  PREG->u.Osbpi.i;   
-	fprintf(stderr,"ensuring %ld\n", sz);
+	PREG = NEXTOP(PREG,Osbpi);
-	PREG = NEXTOP(PREG,ip);
 	if (Unsigned(H) + sz > Unsigned(YREG)-CreepFlag) {
+	  YENV[E_CP] = (CELL) CPREG;
+	  YENV[E_E] = (CELL) ENV;
+#ifdef DEPTH_LIMIT
+	  YENV[E_DEPTH] = DEPTH;
+#endif	/* DEPTH_LIMIT */
 	  ASP = YREG+E_CB;
 	  if (ASP > (CELL *)PROTECT_FROZEN_B(B))
 	    ASP = (CELL *)PROTECT_FROZEN_B(B);
 	  saveregs();
-	  if (!Yap_gcl(sz, 0, ENV, NEXTOP(PREG,ip))) {
+	  if (!Yap_gcl(sz, 0, YENV, PREG)) {
-	    PREG = NEXTOP(PREG,ip);
 	    Yap_Error(OUT_OF_STACK_ERROR,TermNil,Yap_ErrorMessage);
 	    setregs();
 	    FAIL();

C/amasm.c

@@ -1098,13 +1098,15 @@ a_blob(CELL rnd1, op_numbers opcode, int *clause_has_blobsp, yamop *code_p, int
 static yamop *
 a_ensure_space(op_numbers opcode, yamop *code_p, int pass_no, struct intermediates *cip, clause_info *clinfo) 
 {
-  if (cip->cpc->rnd1 > 4096 && FALSE) {
+  if (cip->cpc->rnd1 > 4096) {
     if (pass_no) {
       code_p->opc = emit_op(opcode);
-      code_p->u.ip.i = sizeof(CELL) * cip->cpc->rnd1;
+      code_p->u.Osbpi.i = sizeof(CELL) * cip->cpc->rnd1;
-      code_p->u.ip.p = clinfo->CurrentPred;
+      code_p->u.Osbpi.p = clinfo->CurrentPred;
+      code_p->u.Osbpi.bmap = NULL;
+      code_p->u.Osbpi.s = emit_count(-Signed(RealEnvSize));
     }
-    GONEXT(ip);
+    GONEXT(Osbpi);
   }
   return code_p;
 }

H/YapOpcodes.h

@@ -24,7 +24,7 @@
   OPCODE(alloc_for_logical_pred     ,L),
   OPCODE(copy_idb_term              ,e),
   OPCODE(unify_idb_term             ,e),
-  OPCODE(ensure_space               ,ip),
+  OPCODE(ensure_space               ,Osbpi),
   OPCODE(spy_or_trymark             ,Otapl),
   OPCODE(try_and_mark               ,Otapl),
   OPCODE(count_retry_and_mark       ,Otapl),

H/amidefs.h

@@ -654,6 +654,16 @@ typedef struct yami {
     struct {
 #ifdef YAPOR
       unsigned int        or_arg;
+#endif
+      COUNT               s;
+      CELL               *bmap;
+      struct pred_entry  *p;
+      Int		  i;
+      CELL next;
+    } Osbpi;
+    struct {
+#ifdef YAPOR
+      unsigned int        or_arg;
 #endif
       COUNT               s;
       CELL               *bmap;

H/findclause.h

@@ -9,6 +9,9 @@
     case _alloc_for_logical_pred:
       cl = NEXTOP(cl,L);
       break;
+    case _ensure_space:
+      cl = NEXTOP(cl,Osbpi);
+      break;
     case _native_me:
       cl = NEXTOP(cl,aFlp);
       break;
@@ -289,9 +292,6 @@
     case _write_longint:
       cl = NEXTOP(cl,i);
       break;
-    case _ensure_space:
-      cl = NEXTOP(cl,ip);
-      break;
     case _unify_l_list:
       cl = NEXTOP(cl,o);
       break;

H/rclause.h

@@ -44,10 +44,16 @@ restore_opcodes(yamop *pc, yamop *max)
     case _p_execute:
       OrArgAdjust(pc->u.Osbmp.or_arg);
       pc->u.Osbmp.s = ConstantAdjust(pc->u.Osbmp.s);
-      pc->u.Osbmp.bmap = CellPtoHeapAdjust(pc->u.Osbmp.bmap);
+      pc->u.Osbmp.mod = CellPtoHeapAdjust(pc->u.Osbmp.mod);
-      pc->u.Osbmp.mod = ModuleAdjust(pc->u.Osbmp.mod);
+      pc->u.Osbmp.p0 = ModuleAdjust(pc->u.Osbmp.p0);
-      pc->u.Osbmp.p0 = PtoPredAdjust(pc->u.Osbmp.p0);
+      /* instructions type Osbpi */
-      pc = NEXTOP(pc,Osbmp);
+    case _ensure_space:
+      OrArgAdjust(pc->u.Osbpi.or_arg);
+      pc->u.Osbpi.s = ConstantAdjust(pc->u.Osbpi.s);
+      pc->u.Osbpi.bmap = CellPtoHeapAdjust(pc->u.Osbpi.bmap);
+      pc->u.Osbpi.p = PtoPredAdjust(pc->u.Osbpi.p);
+      IntegerInCodeAdjust(pc->u.Osbpi.i);
+      pc = NEXTOP(pc,Osbpi);
       break;
       /* instructions type Osbpp */
     case _call:
@@ -240,12 +246,6 @@ restore_opcodes(yamop *pc, yamop *max)
       IntegerInCodeAdjust(pc->u.i.i);
       pc = NEXTOP(pc,i);
       break;
-      /* instructions type ip */
-    case _ensure_space:
-      IntegerInCodeAdjust(pc->u.ip.i);
-      pc->u.ip.p = PtoPredAdjust(pc->u.ip.p);
-      pc = NEXTOP(pc,ip);
-      break;
       /* instructions type l */
     case _Ystop:
     case _jump:

H/walkclause.h

@@ -26,6 +26,10 @@
     case _p_execute:
       pc = NEXTOP(pc,Osbmp);
       break;
+      /* instructions type Osbpi */
+    case _ensure_space:
+      pc = NEXTOP(pc,Osbpi);
+      break;
       /* instructions type Osbpp */
     case _call_cpred:
       pp = pc->u.Osbpp.p;
@@ -184,10 +188,6 @@
     case _write_longint:
       pc = NEXTOP(pc,i);
       break;
-      /* instructions type ip */
-    case _ensure_space:
-      pc = NEXTOP(pc,ip);
-      break;
       /* instructions type l */
     case _Ystop:
       return found_ystop(pc, clause_code, startp, endp, pp);