- {
-
- /* if this is an ipop that means some live
- range will have to be assigned again */
- if (ic->op == IPOP)
- {
- wassert (0);
- reassignLR (IC_LEFT (ic));
- }
-
- /* if result is present && is a true symbol */
- if (IC_RESULT (ic) && ic->op != IFX &&
- IS_TRUE_SYMOP (IC_RESULT (ic)))
- OP_SYMBOL (IC_RESULT (ic))->allocreq = 1;
-
- /* take away registers from live
- ranges that end at this instruction */
- deassignLRs (ic, ebbs[i]);
-
- /* some don't need registers */
- /* MLH: removed RESULT and POINTER_SET condition */
- if (SKIP_IC2 (ic) ||
- ic->op == JUMPTABLE ||
- ic->op == IFX ||
- ic->op == IPUSH ||
- ic->op == IPOP)
- continue;
-
- /* now we need to allocate registers only for the result */
- if (IC_RESULT (ic))
- {
- symbol *sym = OP_SYMBOL (IC_RESULT (ic));
- bitVect *spillable;
- int willCS;
- int j;
-
- D (D_ALLOC, ("serialRegAssign: in loop on result %p\n", sym));
-
- /* if it does not need or is spilt
- or is already assigned to registers
- or will not live beyond this instructions */
- if (!sym->nRegs ||
- sym->isspilt ||
- bitVectBitValue (_G.regAssigned, sym->key) ||
- sym->liveTo <= ic->seq)
- {
- D (D_ALLOC, ("serialRegAssign: wont live long enough.\n"));
- continue;
- }
-
- /* if some liverange has been spilt at the block level
- and this one live beyond this block then spil this
- to be safe */
- if (_G.blockSpil && sym->liveTo > ebbs[i]->lSeq)
- {
- D (D_ALLOC, ("serialRegAssign: \"spilling to be safe.\"\n"));
- spillThis (sym);
- continue;
- }
- /* if trying to allocate this will cause
- a spill and there is nothing to spill
- or this one is rematerializable then
- spill this one */
- willCS = willCauseSpill (sym->nRegs, sym->regType);
- spillable = computeSpillable (ic);
- if (sym->remat ||
- (willCS && bitVectIsZero (spillable)))
- {
-
- D (D_ALLOC, ("serialRegAssign: \"remat spill\"\n"));
- spillThis (sym);
- continue;
-
- }
-
- /* if it has a spillocation & is used less than
- all other live ranges then spill this */
- if (willCS) {
- if (sym->usl.spillLoc) {
- symbol *leastUsed = leastUsedLR (liveRangesWith (spillable,
- allLRs, ebbs[i], ic));
- if (leastUsed && leastUsed->used > sym->used) {
- spillThis (sym);
- continue;
- }
- } else {
- /* if none of the liveRanges have a spillLocation then better
- to spill this one than anything else already assigned to registers */
- if (liveRangesWith(spillable,noSpilLoc,ebbs[i],ic)) {
- spillThis (sym);
- continue;
- }
- }
- }
-
- /* else we assign registers to it */
- _G.regAssigned = bitVectSetBit (_G.regAssigned, sym->key);
-
- /* Special case: Try to fit into a reg pair if
- available */
- D (D_ALLOC, ("serialRegAssign: actually allocing regs!\n"));
- if ((sym->nRegs == 2) && tryAllocatingRegPair (sym))
- {
- }
- else
- {
- for (j = 0; j < sym->nRegs; j++)
- {
- sym->regs[j] = getRegGpr (ic, ebbs[i], sym);
-
- /* if the allocation falied which means
- this was spilt then break */
- if (!sym->regs[j])
- {
- D (D_ALLOC, ("Couldnt alloc (spill)\n"))
- break;
- }
- }
- }
- /* if it shares registers with operands make sure
- that they are in the same position */
- if (IC_LEFT (ic) && IS_SYMOP (IC_LEFT (ic)) &&
- OP_SYMBOL (IC_LEFT (ic))->nRegs && ic->op != '=')
- positionRegs (OP_SYMBOL (IC_RESULT (ic)),
- OP_SYMBOL (IC_LEFT (ic)), ic->lineno);
- /* do the same for the right operand */
- if (IC_RIGHT (ic) && IS_SYMOP (IC_RIGHT (ic)) &&
- OP_SYMBOL (IC_RIGHT (ic))->nRegs)
- positionRegs (OP_SYMBOL (IC_RESULT (ic)),
- OP_SYMBOL (IC_RIGHT (ic)), ic->lineno);
-
- }
- }
+ {
+
+ /* if this is an ipop that means some live
+ range will have to be assigned again */
+ if (ic->op == IPOP)
+ {
+ wassert (0);
+ reassignLR (IC_LEFT (ic));
+ }
+
+ /* if result is present && is a true symbol */
+ if (IC_RESULT (ic) && ic->op != IFX &&
+ IS_TRUE_SYMOP (IC_RESULT (ic)))
+ OP_SYMBOL (IC_RESULT (ic))->allocreq++;
+
+ /* take away registers from live
+ ranges that end at this instruction */
+ deassignLRs (ic, ebbs[i]);
+
+ /* some don't need registers */
+ /* MLH: removed RESULT and POINTER_SET condition */
+ if (SKIP_IC2 (ic) ||
+ ic->op == JUMPTABLE ||
+ ic->op == IFX ||
+ ic->op == IPUSH ||
+ ic->op == IPOP)
+ continue;
+
+ /* now we need to allocate registers only for the result */
+ if (IC_RESULT (ic))
+ {
+ symbol *sym = OP_SYMBOL (IC_RESULT (ic));
+ bitVect *spillable;
+ int willCS;
+ int j;
+
+ D (D_ALLOC, ("serialRegAssign: in loop on result %p\n", sym));
+
+ /* Make sure any spill location is definately allocated */
+ if (sym->isspilt && !sym->remat && sym->usl.spillLoc &&
+ !sym->usl.spillLoc->allocreq)
+ {
+ sym->usl.spillLoc->allocreq++;
+ }
+
+ /* if it does not need or is spilt
+ or is already assigned to registers
+ or will not live beyond this instructions */
+ if (!sym->nRegs ||
+ sym->isspilt ||
+ bitVectBitValue (_G.regAssigned, sym->key) ||
+ sym->liveTo <= ic->seq)
+ {
+ D (D_ALLOC, ("serialRegAssign: wont live long enough.\n"));
+ continue;
+ }
+
+ /* if some liverange has been spilt at the block level
+ and this one live beyond this block then spil this
+ to be safe */
+ if (_G.blockSpil && sym->liveTo > ebbs[i]->lSeq)
+ {
+ D (D_ALLOC, ("serialRegAssign: \"spilling to be safe.\"\n"));
+ spillThis (sym);
+ continue;
+ }
+ /* if trying to allocate this will cause
+ a spill and there is nothing to spill
+ or this one is rematerializable then
+ spill this one */
+ willCS = willCauseSpill (sym->nRegs, sym->regType);
+ spillable = computeSpillable (ic);
+ if (sym->remat ||
+ (willCS && bitVectIsZero (spillable)))
+ {
+
+ D (D_ALLOC, ("serialRegAssign: \"remat spill\"\n"));
+ spillThis (sym);
+ continue;
+
+ }
+
+ /* If the live range preceeds the point of definition
+ then ideally we must take into account registers that
+ have been allocated after sym->liveFrom but freed
+ before ic->seq. This is complicated, so spill this
+ symbol instead and let fillGaps handle the allocation. */
+ if (sym->liveFrom < ic->seq)
+ {
+ spillThis (sym);
+ continue;
+ }
+
+ /* if it has a spillocation & is used less than
+ all other live ranges then spill this */
+ if (willCS) {
+ if (sym->usl.spillLoc) {
+ symbol *leastUsed = leastUsedLR (liveRangesWith (spillable,
+ allLRs, ebbs[i], ic));
+ if (leastUsed && leastUsed->used > sym->used) {
+ spillThis (sym);
+ continue;
+ }
+ } else {
+ /* if none of the liveRanges have a spillLocation then better
+ to spill this one than anything else already assigned to registers */
+ if (liveRangesWith(spillable,noSpilLoc,ebbs[i],ic)) {
+ /* if this is local to this block then we might find a block spil */
+ if (!(sym->liveFrom >= ebbs[i]->fSeq && sym->liveTo <= ebbs[i]->lSeq)) {
+ spillThis (sym);
+ continue;
+ }
+ }
+ }
+ }
+
+ /* else we assign registers to it */
+ _G.regAssigned = bitVectSetBit (_G.regAssigned, sym->key);
+ _G.totRegAssigned = bitVectSetBit (_G.totRegAssigned, sym->key);
+
+ /* Special case: Try to fit into a reg pair if
+ available */
+ D (D_ALLOC, ("serialRegAssign: actually allocing regs!\n"));
+ if ((sym->nRegs == 2) && tryAllocatingRegPair (sym))
+ {
+ }
+ else
+ {
+ for (j = 0; j < sym->nRegs; j++)
+ {
+ sym->regs[j] = getRegGpr (ic, ebbs[i], sym);
+
+ /* if the allocation falied which means
+ this was spilt then break */
+ if (!sym->regs[j])
+ {
+ D (D_ALLOC, ("Couldnt alloc (spill)\n"))
+ break;
+ }
+ }
+ /* Make sure we didn't allocate a register pair with bytes swapped */
+ if(sym->nRegs == 2 && sym->regs[0] == sym->regs[1] + 1 && sym->regs[0] != ®sZ80[2])
+ {
+ freeReg(sym->regs[0]);
+ freeReg(sym->regs[1]);
+ if(!tryAllocatingRegPair(sym))
+ wassertl(0, "Failed to swap register pair bytes back.");
+ }
+ }
+ /* if it shares registers with operands make sure
+ that they are in the same position */
+ if (IC_LEFT (ic) && IS_SYMOP (IC_LEFT (ic)) &&
+ OP_SYMBOL (IC_LEFT (ic))->nRegs && ic->op != '=')
+ positionRegs (OP_SYMBOL (IC_RESULT (ic)),
+ OP_SYMBOL (IC_LEFT (ic)));
+ /* do the same for the right operand */
+ if (IC_RIGHT (ic) && IS_SYMOP (IC_RIGHT (ic)) &&
+ OP_SYMBOL (IC_RIGHT (ic))->nRegs)
+ positionRegs (OP_SYMBOL (IC_RESULT (ic)),
+ OP_SYMBOL (IC_RIGHT (ic)));
+
+ }
+ }
+ }
+
+ /* Check for and fix any problems with uninitialized operands */
+ for (i = 0; i < count; i++)
+ {
+ iCode *ic;
+
+ if (ebbs[i]->noPath &&
+ (ebbs[i]->entryLabel != entryLabel &&
+ ebbs[i]->entryLabel != returnLabel))
+ continue;
+
+ for (ic = ebbs[i]->sch; ic; ic = ic->next)
+ {
+ if (SKIP_IC2 (ic))
+ continue;
+
+ if (ic->op == IFX)
+ {
+ verifyRegsAssigned (IC_COND (ic), ic);
+ continue;
+ }
+
+ if (ic->op == JUMPTABLE)
+ {
+ verifyRegsAssigned (IC_JTCOND (ic), ic);
+ continue;
+ }
+
+ verifyRegsAssigned (IC_RESULT (ic), ic);
+ verifyRegsAssigned (IC_LEFT (ic), ic);
+ verifyRegsAssigned (IC_RIGHT (ic), ic);
+ }
+ }
+
+}
+
+/*-----------------------------------------------------------------*/
+/* fillGaps - Try to fill in the Gaps left by Pass1 */
+/*-----------------------------------------------------------------*/
+static void fillGaps()
+{
+ symbol *sym =NULL;
+ int key =0;
+
+ if (getenv("DISABLE_FILL_GAPS")) return;
+
+ /* look for livernages that was spilt by the allocator */
+ for (sym = hTabFirstItem(liveRanges,&key) ; sym ;
+ sym = hTabNextItem(liveRanges,&key)) {
+
+ int i;
+ int pdone = 0;
+
+ if (!sym->spillA || !sym->clashes || sym->remat) continue ;
+
+ /* find the liveRanges this one clashes with, that are
+ still assigned to registers & mark the registers as used*/
+ for ( i = 0 ; i < sym->clashes->size ; i ++) {
+ int k;
+ symbol *clr;
+
+ if (bitVectBitValue(sym->clashes,i) == 0 || /* those that clash with this */
+ bitVectBitValue(_G.totRegAssigned,i) == 0) /* and are still assigned to registers */
+ continue ;
+
+ clr = hTabItemWithKey(liveRanges,i);
+ assert(clr);
+
+ /* mark these registers as used */
+ for (k = 0 ; k < clr->nRegs ; k++ )
+ useReg(clr->regs[k]);
+ }
+
+ if (willCauseSpill(sym->nRegs,sym->regType)) {
+ /* NOPE :( clear all registers & and continue */
+ freeAllRegs();
+ continue ;
+ }
+
+ /* THERE IS HOPE !!!! */
+ for (i=0; i < sym->nRegs ; i++ ) {
+ sym->regs[i] = getRegGprNoSpil ();
+ }
+
+ /* for all its definitions check if the registers
+ allocated needs positioning NOTE: we can position
+ only ONCE if more than One positioning required
+ then give up */
+ sym->isspilt = 0;
+ for (i = 0 ; i < sym->defs->size ; i++ ) {
+ if (bitVectBitValue(sym->defs,i)) {
+ iCode *ic;
+ if (!(ic = hTabItemWithKey(iCodehTab,i))) continue ;
+ if (SKIP_IC(ic)) continue;
+ assert(isSymbolEqual(sym,OP_SYMBOL(IC_RESULT(ic)))); /* just making sure */
+ /* if left is assigned to registers */
+ if (IS_SYMOP(IC_LEFT(ic)) &&
+ bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_LEFT(ic))->key)) {
+ pdone += positionRegs(sym,OP_SYMBOL(IC_LEFT(ic)));
+ }
+ if (IS_SYMOP(IC_RIGHT(ic)) &&
+ bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_RIGHT(ic))->key)) {
+ pdone += positionRegs(sym,OP_SYMBOL(IC_RIGHT(ic)));
+ }
+ if (pdone > 1) break;
+ }
+ }
+ for (i = 0 ; i < sym->uses->size ; i++ ) {
+ if (bitVectBitValue(sym->uses,i)) {
+ iCode *ic;
+ if (!(ic = hTabItemWithKey(iCodehTab,i))) continue ;
+ if (SKIP_IC(ic)) continue;
+ if (!IS_ASSIGN_ICODE(ic)) continue ;
+
+ /* if result is assigned to registers */
+ if (IS_SYMOP(IC_RESULT(ic)) &&
+ bitVectBitValue(_G.totRegAssigned,OP_SYMBOL(IC_RESULT(ic))->key)) {
+ pdone += positionRegs(sym,OP_SYMBOL(IC_RESULT(ic)));
+ }
+ if (pdone > 1) break;
+ }
+ }
+ /* had to position more than once GIVE UP */
+ if (pdone > 1) {
+ /* UNDO all the changes we made to try this */
+ sym->isspilt = 1;
+ for (i=0; i < sym->nRegs ; i++ ) {
+ sym->regs[i] = NULL;
+ }
+ freeAllRegs();
+ D(D_FILL_GAPS,("Fill Gap gave up due to positioning for %s in function %s\n",sym->name, currFunc ? currFunc->name : "UNKNOWN"));
+ continue ;
+ }
+ D(D_FILL_GAPS,("FILLED GAP for %s in function %s\n",sym->name, currFunc ? currFunc->name : "UNKNOWN"));
+ _G.totRegAssigned = bitVectSetBit(_G.totRegAssigned,sym->key);
+ sym->isspilt = sym->spillA = 0 ;
+ sym->usl.spillLoc->allocreq--;
+ freeAllRegs();