* src/regression/Makefile: add -L path to fresh library
[fw/sdcc] / src / pic / pcode.c
index 4067610bc8d8ade88c00e1173db246cedf7fc96b..9f395b10ae8e585d2f83d7ba13088718ce09d68b 100644 (file)
@@ -31,7 +31,7 @@
 
 pCode *findFunction(char *fname);
 
-static void FixRegisterBanking(pBlock *pb,int cur_bank);
+static void FixRegisterBanking(pBlock *pb);
 
 #if defined(__BORLANDC__) || defined(_MSC_VER)
 #define STRCASECMP stricmp
@@ -2360,6 +2360,25 @@ pCodeOp *newpCodeOpBit(char *name, int ibit, int inBitSpace)
        return pcop;
 }
 
+#if 0
+pCodeOp *newpCodeOpBitReg(regs *reg, int ibit, int inBitSpace)
+{
+    pCodeOp *pcop;
+
+    assert(reg);
+
+    pcop = Safe_calloc(1,sizeof(pCodeOpRegBit));
+    pcop->name = reg->name;
+    pcop->type = PO_GPR_BIT;
+    PCORB(pcop)->bit = ibit;
+    PCORB(pcop)->inBitSpace = inBitSpace;
+    PCOR(pcop)->r = reg;
+    PCOR(pcop)->index = 0;
+    PCOR(pcop)->rIdx = reg->rIdx;
+    return pcop;
+}
+#endif
+
 /*-----------------------------------------------------------------*
 * pCodeOp *newpCodeOpReg(int rIdx) - allocate a new register
 *
@@ -4489,7 +4508,7 @@ void pCodeReplace (pCode *old, pCode *new)
        /* special handling for pCodeInstructions */
        if (isPCI(new) && isPCI(old))
        {
-               assert (!PCI(new)->from && !PCI(new)->to && !PCI(new)->label && /*!PCI(new)->pcflow && */!PCI(new)->cline);
+               //assert (!PCI(new)->from && !PCI(new)->to && !PCI(new)->label && /*!PCI(new)->pcflow && */!PCI(new)->cline);
                PCI(new)->from = PCI(old)->from;
                PCI(new)->to = PCI(old)->to;
                PCI(new)->label = PCI(old)->label;
@@ -4500,6 +4519,27 @@ void pCodeReplace (pCode *old, pCode *new)
        old->destruct (old);
 }
 
+/*-----------------------------------------------------------------*/
+/*-----------------------------------------------------------------*/
+void addpCodeComment(pCode *pc, const char *fmt, ...)
+{
+    va_list ap;
+    char buffer[4096];
+    pCode *newpc;
+
+    va_start(ap, fmt);
+    if (options.verbose || debug_verbose) {
+       buffer[0] = ';';
+       buffer[1] = ' ';
+       vsprintf(&buffer[2], fmt, ap);
+
+       newpc = newpCodeCharP(&buffer[0]); // strdup's the string
+       pCodeInsertAfter(pc, newpc);
+    }
+    va_end(ap);
+}
+
+void pBlockMergeLabels(pBlock *pb);
 /*-----------------------------------------------------------------*/
 /* Inserts a new pCodeInstruction before an existing one           */
 /*-----------------------------------------------------------------*/
@@ -4547,7 +4587,7 @@ static void insertPCodeInstruction(pCodeInstruction *pci, pCodeInstruction *new_
                case POC_DECFSZW:
                    // These are turned into non-skipping instructions, so
                    // insert 'BTFSC STATUS, Z' after pcprev
-                   pCodeInsertAfter (pcprev, newpCode(POC_BTFSC, popCopyGPR2Bit(PCOP(&pc_status), PIC_Z_BIT)));
+                   pCodeInsertAfter (jump->prev, newpCode(POC_BTFSC, popCopyGPR2Bit(PCOP(&pc_status), PIC_Z_BIT)));
                    break;
                default:
                    // no special actions required
@@ -4556,21 +4596,10 @@ static void insertPCodeInstruction(pCodeInstruction *pci, pCodeInstruction *new_
                pCodeReplace (pcprev, pCodeInstructionCopy (PCI(pcprev), 1));
                pcprev = NULL;
                pCodeInsertAfter((pCode*)pci, label);
+               pBlockMergeLabels(pci->pc.pb);
        }
 }
 
-/*-----------------------------------------------------------------*/
-/*-----------------------------------------------------------------*/
-#if 0
-static void insertBankSwitch(pCodeInstruction *pci, int Set_Clear, int RP_BankBit)
-{
-       pCode *new_pc;
-       
-       new_pc = newpCode((Set_Clear?POC_BSF:POC_BCF),popCopyGPR2Bit(PCOP(&pc_status),RP_BankBit));
-       
-       insertPCodeInstruction(pci, PCI(new_pc));
-}
-#endif
 /*-----------------------------------------------------------------*/
 /*-----------------------------------------------------------------*/
 static void insertBankSel(pCodeInstruction  *pci, const char *name)
@@ -4581,6 +4610,8 @@ static void insertBankSel(pCodeInstruction  *pci, const char *name)
 
        // This is a NOP for single-banked devices.
        if (pic14_getMaxRam() < 0x80) return;
+       // Never BANKSEL STATUS, this breaks all kinds of code (e.g., interrupt handlers).
+       if (!strcmp("STATUS", name) || !strcmp("_STATUS", name)) return;
        
        pcop = popCopyReg(PCOR(pci->pcop));
        pcop->type = PO_GPR_REGISTER; // Sometimes the type is set to legacy 8051 - so override it
@@ -4592,512 +4623,100 @@ static void insertBankSel(pCodeInstruction  *pci, const char *name)
 }
 
 /*-----------------------------------------------------------------*/
-/* If the register is a fixed known addess then we can assign the  */
-/* bank selection bits. Otherwise the linker is going to assign    */
-/* the register location and thus has to set bank selection bits   */
-/* through the banksel directive.                                  */
-/* One critical assumption here is that within this C module all   */ 
-/* the locally allocated registers are in the same udata sector.   */
-/* Therefore banksel is only called for external registers or the  */
-/* first time a local register is encountered.                     */
 /*-----------------------------------------------------------------*/
-static int LastRegIdx = -1; /* If the previous register is the same one again then no need to change bank. */
-static int BankSelect(pCodeInstruction *pci, int cur_bank, regs *reg)
+static int sameBank(regs *reg, const char *new_bank, const char *cur_bank)
 {
-#if 1
-       /* Always insert BANKSELs rather than try to be clever:
-        * Too many bugs in optimized banksels... */
-       static PIC_device *pic;
-       if (!pic) pic = pic14_getPIC();
+    if (!cur_bank) return 0;
 
-       // possible optimizations:
-       // * do not emit BANKSELs for SFRs that are present in all banks (bankmsk == regmap for this register)
-       if (reg && pic && ((reg->alias & pic->bankMask) == pic->bankMask)) return 'L';
-       
-       insertBankSel(pci, reg->name); // Let linker choose the bank selection
-       return 'L';
-#else
-       int bank;
-       int a = reg->alias>>7;
-       if ((a&3) == 3) {
-               return cur_bank; // This register is available in all banks
-       } else if ((a&1)&&((cur_bank==0)||(cur_bank==1))) {
-               return cur_bank; // This register is available in banks 0 & 1
-       } else if (a&2) {
-               if (reg->address&0x80) {
-                       if ((cur_bank==1)||(cur_bank==3)) {
-                               return cur_bank; // This register is available in banks 1 & 3
-                       }
-               } else {
-                       if ((cur_bank==0)||(cur_bank==1)) {
-                               return cur_bank; // This register is available in banks 0 & 2
-                       }
-               }
-       }
-       
-#if 1
-       if (LastRegIdx == reg->rIdx) // If this is the same register as last time then it is in same bank
-               return cur_bank;
-       LastRegIdx = reg->rIdx;
-#endif
-       
-       /* Optimized code---unfortunately this turns out to be buggy
-        * (at least on devices with more than two banks). */
-       if (reg->isFixed) {
-               bank = REG_BANK(reg);
-       } else if (reg->isExtern) {
-               bank = 'E'; // Unfixed extern registers are allocated by the linker therefore its bank is unknown
-       } else {
-               bank = 'L'; // Unfixed local registers are allocated by the linker therefore its bank is unknown
-       }
-       if (bank == 'E' || bank == 'L') { // Reg is now extern and linker to assign bank
-               insertBankSel(pci, reg->name); // Let linker choose the bank selection
-       } else if ((cur_bank == -1)||(cur_bank == 'L')||(cur_bank == 'E')) { // Current bank unknown and new register bank is known then can set bank bits
-               insertBankSwitch(pci, bank&1, PIC_RP0_BIT);
-               if (pic14_getMaxRam()&0x100)
-                       insertBankSwitch(pci, bank&2, PIC_RP1_BIT);
-       } else { // Current bank and new register banks known - can set bank bits
-               switch((cur_bank^bank) & 3) {
-               case 0:
-                       break;
-               case 1:
-                       insertBankSwitch(pci, bank&1, PIC_RP0_BIT);
-                       break;
-               case 2:
-                       insertBankSwitch(pci, bank&2, PIC_RP1_BIT);
-                       break;
-               case 3:
-                       insertBankSwitch(pci, bank&1, PIC_RP0_BIT);
-                       if (pic14_getMaxRam()&0x100)
-                               insertBankSwitch(pci, bank&2, PIC_RP1_BIT);
-                       break;
-               }
-       }
-       
-       return bank;
-#endif
+    // identify '(regname + X)' and 'regname'
+    if (reg && reg->name && reg->name[0] == '(' && !strncmp(&reg->name[1], cur_bank, strlen(cur_bank))) return 1;
+    if (new_bank && new_bank[0] == '(' && !strncmp(&new_bank[1], cur_bank, strlen(cur_bank))) return 1;
+    if (cur_bank[0] == '(' && reg && reg->name && !strncmp(reg->name, &cur_bank[1], strlen(reg->name))) return 1;
+    if (cur_bank[0] == '(' && new_bank && !strncmp(new_bank, &cur_bank[1], strlen(new_bank))) return 1;
+    
+    // XXX: identify '(regname + X)' and '(regname + Y)'
+    
+    return ((reg && reg->name && !strcmp(reg->name, cur_bank)) || (new_bank && !strcmp(new_bank, cur_bank)));
 }
-
+    
 /*-----------------------------------------------------------------*/
-/* Check for bank selection pcodes instructions and modify         */
-/* cur_bank to match.                                              */
 /*-----------------------------------------------------------------*/
-static int IsBankChange(pCode *pc, regs *reg, int *cur_bank) {
-       
-       if (isSTATUS_REG(reg)) {
-               
-               if (PCI(pc)->op == POC_BCF) {
-                       int old_bank = *cur_bank;
-                       if (PCORB(PCI(pc)->pcop)->bit == PIC_RP0_BIT) {
-                               /* If current bank is unknown or linker assigned then set to 0 else just change the bit */
-                               if (*cur_bank & ~(0x3))
-                                       *cur_bank = 0;
-                               else
-                                       *cur_bank = *cur_bank&0x2;
-                               LastRegIdx = reg->rIdx;
-                       } else if (PCORB(PCI(pc)->pcop)->bit == PIC_RP1_BIT) {
-                               /* If current bank is unknown or linker assigned then set to 0 else just change the bit */
-                               if (*cur_bank & ~(0x3))
-                                       *cur_bank = 0;
-                               else
-                                       *cur_bank = *cur_bank&0x1;
-                               LastRegIdx = reg->rIdx;
-                       }
-                       return old_bank != *cur_bank;
-               }
-               
-               if (PCI(pc)->op == POC_BSF) {
-                       int old_bank = *cur_bank;
-                       if (PCORB(PCI(pc)->pcop)->bit == PIC_RP0_BIT) {
-                               /* If current bank is unknown or linker assigned then set to bit else just change the bit */
-                               if (*cur_bank & ~(0x3))
-                                       *cur_bank = 0x1;
-                               else
-                                       *cur_bank = (*cur_bank&0x2) | 0x1;
-                               LastRegIdx = reg->rIdx;
-                       } else if (PCORB(PCI(pc)->pcop)->bit == PIC_RP1_BIT) {
-                               /* If current bank is unknown or linker assigned then set to bit else just change the bit */
-                               if (*cur_bank & ~(0x3))
-                                       *cur_bank = 0x2;
-                               else
-                                       *cur_bank = (*cur_bank&0x1) | 0x2;
-                               LastRegIdx = reg->rIdx;
-                       }
-                       return old_bank != *cur_bank;
-               }
-               
-       } else if (PCI(pc)->op == POC_BANKSEL) {
-               int old_bank = *cur_bank;
-               regs *r = PCOR(PCI(pc)->pcop)->r;
-               *cur_bank = (!r || r->isExtern) ? 'E' : 'L';
-               LastRegIdx = reg->rIdx;
-               return old_bank != *cur_bank;
-       }
-       
-       return 0;
-}
+void FixRegisterBanking(pBlock *pb)
+{
+    pCode *pc;
+    pCodeInstruction *pci;
+    regs *reg;
+    const char *cur_bank, *new_bank;
+    unsigned cur_mask, new_mask, max_mask;
+    
+    if (!pb) return;
 
-/*-----------------------------------------------------------------*/
-/* Set bank selection if necessary                                 */
-/*-----------------------------------------------------------------*/
-static int DoBankSelect(pCode *pc, int cur_bank) {
-       pCode *pcprev;
-       regs *reg;
-       
-       if(!isPCI(pc))
-               return cur_bank;
-       
-       if (isCALL(pc)) {
-               pCode *pcf = findFunction(get_op_from_instruction(PCI(pc)));
-               LastRegIdx = -1; /* do not know which register is touched in the called function... */
-               if (pcf && isPCF(pcf)) {
-                       pCode *pcfr;
-                       int rbank = 'U'; // Undetermined
-                       FixRegisterBanking(pcf->pb,cur_bank); // Ensure this block has had its banks selection done
-                       // Check all the returns to work out what bank is selected
-                       for (pcfr=pcf->pb->pcHead; pcfr; pcfr=pcfr->next) {
-                               if (isPCI(pcfr)) {
-                                       if ((PCI(pcfr)->op==POC_RETURN) || (PCI(pcfr)->op==POC_RETLW)) {
-                                               if (rbank == 'U')
-                                                       rbank = PCI(pcfr)->pcflow->lastBank;
-                                               else
-                                                       if (rbank != PCI(pcfr)->pcflow->lastBank)
-                                                               return -1; // Unknown bank - multiple returns with different banks
-                                       }
-                               }
-                       }
-                       if (rbank == 'U')
-                               return -1; // Unknown bank
-                       return rbank;
-               } else if (isPCOS(PCI(pc)->pcop) && PCOS(PCI(pc)->pcop)->isPublic) {
-                       /* Extern functions may use registers in different bank - must call banksel */
-                       return -1; /* Unknown bank */
-               }
-               /* play safe... */
-               return -1;
-       }
-       
-       if ((isPCI(pc)) && (PCI(pc)->op == POC_BANKSEL)) {
-               return -1; /* New bank unknown - linkers choice. */
-       }
-       
-       reg = getRegFromInstruction(pc);
-       if (!reg && isPCI(pc) &&
-               ((PCI(pc)->inCond | PCI(pc)->outCond) & PCC_REGISTER))
-       {
-           if (PCI(pc)->pcop && PCI(pc)->pcop->type == PO_IMMEDIATE) {
-               // fine, this should be low(variable) --> no BANKING required
-           } else {
-               assert(!"Could not get register from instruction.");
-           }
-       }
-       if (reg) {
-               if (IsBankChange(pc,reg,&cur_bank))
-                       return cur_bank;
-               if (!isPCI_LIT(pc)) {
-                       
-                       /* Examine the instruction before this one to make sure it is
-                       * not a skip type instruction */
-                       pcprev = findPrevpCode(pc->prev, PC_OPCODE);
-                       
-                       /* This approach does not honor the presence of labels at this instruction... */
-                       //if(!pcprev || (pcprev && !isPCI_SKIP(pcprev))) {
-                               cur_bank = BankSelect(PCI(pc),cur_bank,reg);
-                       //} else {
-                       //      cur_bank = BankSelect(PCI(pcprev),cur_bank,reg);
-                       //}
-                       if (!PCI(pc)->pcflow)
-                               fprintf(stderr,"PCI ID=%d missing flow pointer ???\n",pc->id);
-                       else
-                               PCI(pc)->pcflow->lastBank = cur_bank; /* Maintain pCodeFlow lastBank state */
-               }
-       }
-       return cur_bank;
-}
+    max_mask = pic14_getPIC()->bankMask;
+    cur_mask = max_mask;
+    cur_bank = NULL;
 
-/*-----------------------------------------------------------------*/
-/*-----------------------------------------------------------------*/
-/*
-static void FixRegisterBankingInFlow(pCodeFlow *pcfl, int cur_bank)
-{
-       pCode *pc=NULL;
-       pCode *pcprev=NULL;
-       
-       if(!pcfl)
-               return;
-       
-       pc = findNextInstruction(pcfl->pc.next);
-       
-       while(isPCinFlow(pc,PCODE(pcfl))) {
-               
-               cur_bank = DoBankSelect(pc,cur_bank);
-               pcprev = pc;
-               pc = findNextInstruction(pc->next);
-               
-       }
-       
-       if(pcprev && cur_bank) {
-               // Set bank state to unknown at the end of each flow block
-               cur_bank = -1;
+    for (pc = pb->pcHead; pc; pc = pc->next)
+    {
+       // this one has a label---might check bank at all jumps here...
+       if (isPCI(pc) && (PCI(pc)->label || PCI(pc)->op == POC_CALL)) {
+           addpCodeComment(pc->prev, "BANKOPT3 drop assumptions: PCI with label or call found");
+           cur_bank = NULL; // start new flow
+           cur_mask = max_mask;
        }
        
-}
-*/
-/*-----------------------------------------------------------------*/
-/*int compareBankFlow - compare the banking requirements between   */
-/*  flow objects. */
-/*-----------------------------------------------------------------*/
-/*
-int compareBankFlow(pCodeFlow *pcflow, pCodeFlowLink *pcflowLink, int toORfrom)
-{
-       
-       if(!pcflow || !pcflowLink || !pcflowLink->pcflow)
-               return 0;
-       
-       if(!isPCFL(pcflow) || !isPCFL(pcflowLink->pcflow))
-               return 0;
-       
-       if(pcflow->firstBank == -1)
-               return 0;
-       
-       
-       if(pcflowLink->pcflow->firstBank == -1) {
-               pCodeFlowLink *pctl = setFirstItem( toORfrom ? 
-                       pcflowLink->pcflow->to : 
-               pcflowLink->pcflow->from);
-               return compareBankFlow(pcflow, pctl, toORfrom);
+       // this one is/might be a label or BANKSEL---assume nothing
+       if (isPCL(pc) || isPCASMDIR(pc)) {
+           addpCodeComment(pc->prev, "BANKOPT4 drop assumptions: label or ASMDIR found");
+           cur_bank = NULL;
+           cur_mask = max_mask;
        }
-       
-       if(toORfrom) {
-               if(pcflow->lastBank == pcflowLink->pcflow->firstBank)
-                       return 0;
-               
-               pcflowLink->bank_conflict++;
-               pcflowLink->pcflow->FromConflicts++;
-               pcflow->ToConflicts++;
-       } else {
-               
-               if(pcflow->firstBank == pcflowLink->pcflow->lastBank)
-                       return 0;
-               
-               pcflowLink->bank_conflict++;
-               pcflowLink->pcflow->ToConflicts++;
-               pcflow->FromConflicts++;
-               
-       }
-       / *
-               fprintf(stderr,"compare flow found conflict: seq %d from conflicts %d, to conflicts %d\n",
-               pcflowLink->pcflow->pc.seq,
-               pcflowLink->pcflow->FromConflicts,
-               pcflowLink->pcflow->ToConflicts);
-       * /
-               return 1;
-       
-}
-*/
-/*-----------------------------------------------------------------*/
-/*-----------------------------------------------------------------*/
-/*
-void FixBankFlow(pBlock *pb)
-{
-       pCode *pc=NULL;
-       pCode *pcflow;
-       pCodeFlowLink *pcfl;
-       
-       pCode *pcflow_max_To=NULL;
-       pCode *pcflow_max_From=NULL;
-       int max_ToConflicts=0;
-       int max_FromConflicts=0;
-       
-       /fprintf(stderr,"Fix Bank flow \n");
-       pcflow = findNextpCode(pb->pcHead, PC_FLOW);
-       
-       
-       / *
-               First loop through all of the flow objects in this pcode block
-               and fix the ones that have banking conflicts between the 
-               entry and exit.
-               * /
-               
-       //fprintf(stderr, "FixBankFlow - Phase 1\n");
-       
-       for( pcflow = findNextpCode(pb->pcHead, PC_FLOW); 
-       pcflow != NULL;
-       pcflow = findNextpCode(pcflow->next, PC_FLOW) ) {
-               
-               if(!isPCFL(pcflow)) {
-                       fprintf(stderr, "FixBankFlow - pcflow is not a flow object ");
-                       continue;
-               }
-               
-               if(PCFL(pcflow)->firstBank != PCFL(pcflow)->lastBank  &&
-                       PCFL(pcflow)->firstBank >= 0 &&
-                       PCFL(pcflow)->lastBank >= 0 ) {
-                       
-                       int cur_bank = (PCFL(pcflow)->firstBank < PCFL(pcflow)->lastBank) ?
-                               PCFL(pcflow)->firstBank : PCFL(pcflow)->lastBank;
-                       
-                       FixRegisterBankingInFlow(PCFL(pcflow),cur_bank);
-                       BanksUsedFlow2(pcflow);
-                       
+
+       // this one modifies STATUS
+       // XXX: this should be checked, but usually BANKSELs are not done this way in generated code
+       
+       if (isPCI(pc)) {
+           pci = PCI(pc);
+           if ((pci->inCond | pci->outCond) & PCC_REGISTER) {
+               // might need a BANKSEL
+               reg = getRegFromInstruction(pc);
+
+               if (reg) {
+                   new_bank = reg->name;
+                   // reg->alias == 0: reg is in only one bank, we do not know which (may be any bank)
+                   // reg->alias != 0: reg is in 2/4/8/2**N banks, we select one of them
+                   new_mask = reg->alias;
+               } else if (pci->pcop && pci->pcop->name) {
+                   new_bank = pci->pcop->name;
+                   new_mask = 0; // unknown, assume worst case
+               } else {
+                   assert(!"Could not get register from instruction.");
                }
-       }
-       
-       //fprintf(stderr, "FixBankFlow - Phase 2\n");
-       
-       for( pcflow = findNextpCode(pb->pcHead, PC_FLOW); 
-       pcflow != NULL;
-       pcflow = findNextpCode(pcflow->next, PC_FLOW) ) {
-               
-               int nFlows;
-               int nConflicts;
-               
-               if(!isPCFL(pcflow)) {
-                       fprintf(stderr, "FixBankFlow - pcflow is not a flow object ");
+
+               // optimizations...
+               // XXX: add switch to disable these
+               if (1) {
+                   // reg present in all banks possibly selected?
+                   if (new_mask == max_mask || (cur_mask && ((new_mask & cur_mask) == cur_mask))) {
+                       // no BANKSEL required
+                       addpCodeComment(pc->prev, "BANKOPT1 BANKSEL dropped; %s present in all of %s's banks", new_bank, cur_bank);
                        continue;
-               }
-               
-               PCFL(pcflow)->FromConflicts = 0;
-               PCFL(pcflow)->ToConflicts = 0;
-               
-               nFlows = 0;
-               nConflicts = 0;
-               
-               //fprintf(stderr, " FixBankFlow flow seq %d\n",pcflow->seq);
-               pcfl = setFirstItem(PCFL(pcflow)->from);
-               while (pcfl) {
-                       
-                       pc = PCODE(pcfl->pcflow);
-                       
-                       if(!isPCFL(pc)) {
-                               fprintf(stderr,"oops dumpflow - to is not a pcflow\n");
-                               pc->print(stderr,pc);
-                       }
-                       
-                       nConflicts += compareBankFlow(PCFL(pcflow), pcfl, 0);
-                       nFlows++;
-                       
-                       pcfl=setNextItem(PCFL(pcflow)->from);
-               }
-               
-               if((nFlows >= 2) && nConflicts && (PCFL(pcflow)->firstBank>0)) {
-                       //fprintf(stderr, " From conflicts flow seq %d, nflows %d ,nconflicts %d\n",pcflow->seq,nFlows, nConflicts);
-                       
-                       FixRegisterBankingInFlow(PCFL(pcflow),-1);
-                       BanksUsedFlow2(pcflow);
-                       
-                       continue;  / * Don't need to check the flow from here - it's already been fixed * /
-                               
-               }
-               
-               nFlows = 0;
-               nConflicts = 0;
-               
-               pcfl = setFirstItem(PCFL(pcflow)->to);
-               while (pcfl) {
-                       
-                       pc = PCODE(pcfl->pcflow);
-                       if(!isPCFL(pc)) {
-                               fprintf(stderr,"oops dumpflow - to is not a pcflow\n");
-                               pc->print(stderr,pc);
-                       }
-                       
-                       nConflicts += compareBankFlow(PCFL(pcflow), pcfl, 1);
-                       nFlows++;
-                       
-                       pcfl=setNextItem(PCFL(pcflow)->to);
-               }
-               
-               if((nFlows >= 2) && nConflicts &&(nConflicts != nFlows) && (PCFL(pcflow)->lastBank>0)) {
-                       //fprintf(stderr, " To conflicts flow seq %d, nflows %d ,nconflicts %d\n",pcflow->seq,nFlows, nConflicts);
-                       
-                       FixRegisterBankingInFlow(PCFL(pcflow),-1);
-                       BanksUsedFlow2(pcflow);
-               }
-       }
-       
-       / *
-               Loop through the flow objects again and find the ones with the 
-               maximum conflicts
-               * /
-               
-               for( pcflow = findNextpCode(pb->pcHead, PC_FLOW); 
-               pcflow != NULL;
-               pcflow = findNextpCode(pcflow->next, PC_FLOW) ) {
-                       
-                       if(PCFL(pcflow)->ToConflicts > max_ToConflicts)
-                               pcflow_max_To = pcflow;
-                       
-                       if(PCFL(pcflow)->FromConflicts > max_FromConflicts)
-                               pcflow_max_From = pcflow;
-               }
-               / *
-                       if(pcflow_max_To)
-                               fprintf(stderr,"compare flow Max To conflicts: seq %d conflicts %d\n",
-                               PCFL(pcflow_max_To)->pc.seq,
-                               PCFL(pcflow_max_To)->ToConflicts);
-                       
-                       if(pcflow_max_From)
-                               fprintf(stderr,"compare flow Max From conflicts: seq %d conflicts %d\n",
-                               PCFL(pcflow_max_From)->pc.seq,
-                               PCFL(pcflow_max_From)->FromConflicts);
-                       * /
-}
-*/
+                   }
 
-/*-----------------------------------------------------------------*/
-/*-----------------------------------------------------------------*/
-void DumpFlow(pBlock *pb)
-{
-       pCode *pc=NULL;
-       pCode *pcflow;
-       pCodeFlowLink *pcfl;
-       
-       
-       fprintf(stderr,"Dump flow \n");
-       pb->pcHead->print(stderr, pb->pcHead);
-       
-       pcflow = findNextpCode(pb->pcHead, PC_FLOW);
-       pcflow->print(stderr,pcflow);
-       
-       for( pcflow = findNextpCode(pb->pcHead, PC_FLOW); 
-       pcflow != NULL;
-       pcflow = findNextpCode(pcflow->next, PC_FLOW) ) {
-               
-               if(!isPCFL(pcflow)) {
-                       fprintf(stderr, "DumpFlow - pcflow is not a flow object ");
+                   cur_mask &= new_mask;
+
+                   if (sameBank(reg, new_bank, cur_bank)) {
+                       // no BANKSEL required
+                       addpCodeComment(pc->prev, "BANKOPT2 BANKSEL dropped; %s present in same bank as %s", new_bank, cur_bank);
                        continue;
-               }
-               fprintf(stderr,"dumping: ");
-               pcflow->print(stderr,pcflow);
-               FlowStats(PCFL(pcflow));
-               
-               for(pcfl = setFirstItem(PCFL(pcflow)->to); pcfl; pcfl=setNextItem(PCFL(pcflow)->to)) {
-                       
-                       pc = PCODE(pcfl->pcflow);
-                       
-                       fprintf(stderr, "    from seq %d:\n",pc->seq);
-                       if(!isPCFL(pc)) {
-                               fprintf(stderr,"oops dumpflow - from is not a pcflow\n");
-                               pc->print(stderr,pc);
-                       }
-                       
-               }
-               
-               for(pcfl = setFirstItem(PCFL(pcflow)->to); pcfl; pcfl=setNextItem(PCFL(pcflow)->to)) {
-                       
-                       pc = PCODE(pcfl->pcflow);
-                       
-                       fprintf(stderr, "    to seq %d:\n",pc->seq);
-                       if(!isPCFL(pc)) {
-                               fprintf(stderr,"oops dumpflow - to is not a pcflow\n");
-                               pc->print(stderr,pc);
-                       }
-                       
-               }
-               
-       }
-       
+                   }
+               } // if
+
+               cur_mask = new_mask;
+               cur_bank = new_bank;
+               insertBankSel(pci, cur_bank);
+           } // if
+       } // if
+    } // for
 }
 
 /*-----------------------------------------------------------------*/
@@ -5387,92 +5006,6 @@ pCodeOp *popCopyGPR2Bit(pCodeOp *pc, int bitval)
        return pcop;
 }
 
-
-/*-----------------------------------------------------------------*/
-/*-----------------------------------------------------------------*/
-static void FixRegisterBanking(pBlock *pb,int cur_bank)
-{
-       pCode *pc;
-       int firstBank = 'U';
-       
-       if(!pb)
-               return;
-       
-       for (pc=pb->pcHead; pc; pc=pc->next) {
-               if (isPCFL(pc)) {
-                       firstBank = PCFL(pc)->firstBank;
-                       break;
-               }
-       }
-       if (firstBank != 'U') {
-               /* This block has already been done */
-               if (firstBank != cur_bank) {
-                       /* This block has started with a different bank - must adjust it */ 
-                       if ((firstBank != -1)&&(firstBank != 'E')) { /* The first bank start off unknown or extern then need not worry as banksel will be called */
-                               while (pc) {
-                                       if (isPCI(pc)) {
-                                               regs *reg = getRegFromInstruction(pc);
-                                               if (reg) {
-                                                       DoBankSelect(pc,cur_bank);
-                                               }
-                                       }
-                                       pc = pc->next;
-                               }
-                       }
-               }
-               return;
-       }
-       
-       /* loop through all of the pCodes within this pblock setting the bank selection, ignoring any branching */
-       LastRegIdx = -1;
-       cur_bank = -1;
-       for (pc=pb->pcHead; pc; pc=pc->next) {
-               if (isPCFL(pc)) {
-                       PCFL(pc)->firstBank = cur_bank;
-                       continue;
-               }
-               cur_bank = DoBankSelect(pc,cur_bank);
-       }
-       
-       /* Trace through branches and set the bank selection as required. */
-       LastRegIdx = -1;
-       cur_bank = -1;
-       for (pc=pb->pcHead; pc; pc=pc->next) {
-               if (isPCFL(pc)) {
-                       PCFL(pc)->firstBank = cur_bank;
-                       continue;
-               }
-               if (isPCI(pc)) {
-                       if (PCI(pc)->op == POC_GOTO) {
-                               int lastRegIdx = LastRegIdx;
-                               pCode *pcb = pc;
-                               /* Trace through branch */
-                               pCode *pcl = findLabel(PCOLAB(PCI(pcb)->pcop));
-                               while (pcl) {
-                                       if (isPCI(pcl)) {
-                                               regs *reg = getRegFromInstruction(pcl);
-                                               if (reg) {
-                                                       int bankUnknown = -1;
-                                                       if (IsBankChange(pcl,reg,&bankUnknown)) /* Look for any bank change */
-                                                               break;
-                                                       if (cur_bank != DoBankSelect(pcl,cur_bank)) /* Set bank selection if necessary */
-                                                               break;
-                                               }
-                                       }
-                                       pcl = pcl->next;
-                               }
-                               LastRegIdx = lastRegIdx;
-                       } else {
-                               /* Keep track out current bank */
-                               regs *reg = getRegFromInstruction(pc);
-                               if (reg)
-                                       IsBankChange(pc,reg,&cur_bank);
-                       }
-               }
-       }
-}
-
-
 /*-----------------------------------------------------------------*/
 /*-----------------------------------------------------------------*/
 void pBlockDestruct(pBlock *pb)
@@ -5678,7 +5211,10 @@ void AnalyzeBanking(void)
        //  for(pb = the_pFile->pbHead; pb; pb = pb->next)
        //    BanksUsedFlow(pb);
        for(pb = the_pFile->pbHead; pb; pb = pb->next)
-               FixRegisterBanking(pb,-1); // cur_bank is unknown
+               FixRegisterBanking(pb);
+
+       AnalyzeFlow(0);
+       AnalyzeFlow(1);
        
 }