+
+char *pic_optype_names[]={
+ "PO_NONE", // No operand e.g. NOP
+ "PO_W", // The working register (as a destination)
+ "PO_WREG", // The working register (as a file register)
+ "PO_STATUS", // The 'STATUS' register
+ "PO_BSR", // The 'BSR' register
+ "PO_FSR0", // The "file select register" (in PIC18 family it's one
+ // of three)
+ "PO_INDF0", // The Indirect register
+ "PO_INTCON", // Interrupt Control register
+ "PO_GPR_REGISTER", // A general purpose register
+ "PO_GPR_BIT", // A bit of a general purpose register
+ "PO_GPR_TEMP", // A general purpose temporary register
+ "PO_SFR_REGISTER", // A special function register (e.g. PORTA)
+ "PO_PCL", // Program counter Low register
+ "PO_PCLATH", // Program counter Latch high register
+ "PO_PCLATU", // Program counter Latch upper register
+ "PO_PRODL", // Product Register Low
+ "PO_PRODH", // Product Register High
+ "PO_LITERAL", // A constant
+ "PO_REL_ADDR", // A relative address
+ "PO_IMMEDIATE", // (8051 legacy)
+ "PO_DIR", // Direct memory (8051 legacy)
+ "PO_CRY", // bit memory (8051 legacy)
+ "PO_BIT", // bit operand.
+ "PO_STR", // (8051 legacy)
+ "PO_LABEL",
+ "PO_WILD", // Wild card operand in peep optimizer
+ "PO_TWO_OPS" // combine two operands
+};
+
+
+char *dumpPicOptype(PIC_OPTYPE type)
+{
+ assert( type >= 0 && type < sizeof(pic_optype_names)/sizeof( char *) );
+ return (pic_optype_names[ type ]);
+}
+
+
+/*** BEGIN of stuff belonging to the BANKSEL optimization ***/
+#include "graph.h"
+
+#define MAX_COMMON_BANK_SIZE 32
+#define FIRST_PSEUDO_BANK_NR 1000
+
+hTab *sym2bank = NULL; // <OPERAND NAME> --> <PSEUDO BANK NR>
+hTab *bank2sym = NULL; // <PSEUDO BANK NR> --> <OPERAND NAME>
+hTab *coerce = NULL; // <PSEUDO BANK NR> --> <&PSEUDOBANK>
+Graph *adj = NULL;
+
+typedef enum { INVALID_BANK = -1, UNKNOWN_BANK = -2, FIXED_BANK = -3 } pseudoBankNr;
+
+typedef struct {
+ pseudoBankNr bank; // number assigned to this pseudoBank
+ unsigned int size; // number of operands assigned to this bank
+ unsigned int ref; // number of symbols referring to this pseudoBank (for garbage collection)
+} pseudoBank;
+
+/*----------------------------------------------------------------------*/
+/* hashSymbol - hash function used to map SYMBOLs (or operands) to ints */
+/*----------------------------------------------------------------------*/
+unsigned int hashSymbol (const char *str)
+{
+ unsigned int res = 0;
+ if (!str) return 0;
+
+ while (*str) {
+ res ^= (*str);
+ res = (res << 4) | (res >> (8 * sizeof(unsigned int) - 4));
+ str++;
+ } // while
+
+ return res;
+}
+
+/*-----------------------------------------------------------------------*/
+/* compareSymbol - return 1 iff sym1 equals sym2 */
+/*-----------------------------------------------------------------------*/
+int compareSymbol (const void *sym1, const void *sym2)
+{
+ char *s1 = (char*) sym1;
+ char *s2 = (char*) sym2;
+
+ return (strcmp (s1,s2) == 0);
+}
+
+/*-----------------------------------------------------------------------*/
+/* comparePre - return 1 iff p1 == p2 */
+/*-----------------------------------------------------------------------*/
+int comparePtr (const void *p1, const void *p2)
+{
+ return (p1 == p2);
+}
+
+/*----------------------------------------------------------*/
+/* getSymbolFromOperand - return a pointer to the symbol in */
+/* the given operand and its length */
+/*----------------------------------------------------------*/
+char *getSymbolFromOperand (char *op, int *len)
+{
+ char *sym, *curr;
+ *len = 0;
+
+ if (!op) return NULL;
+
+ // we recognize two forms of operands: SYMBOL and (SYMBOL + offset)
+ sym = op;
+ if (*sym == '(') sym++;
+
+ curr = sym;
+ while (((*curr >= 'A') && (*curr <= 'Z'))
+ || ((*curr >= 'a') && (*curr <= 'z'))
+ || ((curr != sym) && (*curr >= '0') && (*curr <= '9'))
+ || (*curr == '_')) {
+ // find end of symbol [A-Za-z_]?[A-Za-z0-9]*
+ curr++;
+ (*len)++;
+ } // while
+
+ return sym;
+}
+
+/*--------------------------------------------------------------------------*/
+/* getSymFromBank - get (one) name of a symbol assigned to the given bank */
+/*--------------------------------------------------------------------------*/
+char *getSymFromBank (pseudoBankNr bank)
+{
+ assert (bank2sym);
+
+ if (bank < 0) return "<INVALID BANK NR>";
+ return hTabFindByKey (bank2sym, bank % bank2sym->size, (void *) bank, &comparePtr);
+}
+
+/*-----------------------------------------------------------------------*/
+/* getPseudoBsrFromOperand - maps a string to its corresponding pseudo */
+/* bank number (uses hTab sym2bank), if the */
+/* symbol is not yet assigned a pseudo bank it */
+/* is assigned one here */
+/*-----------------------------------------------------------------------*/
+pseudoBankNr getPseudoBankNrFromOperand (const char *op)
+{
+ static pseudoBankNr next_bank = FIRST_PSEUDO_BANK_NR;
+ pseudoBankNr bank;
+ unsigned int hash;
+
+ assert (sym2bank);
+
+ hash = hashSymbol (op) % sym2bank->size;
+ bank = (pseudoBankNr) hTabFindByKey (sym2bank, hash, op, &compareSymbol);
+ if (bank == (pseudoBankNr)NULL) bank = UNKNOWN_BANK;
+
+ if (bank == UNKNOWN_BANK) {
+ // create a pseudo bank for the operand
+ bank = next_bank++;
+ hTabAddItemLong (&sym2bank, hash, (char *)op, (void *)bank);
+ hTabAddItemLong (&bank2sym, bank, (void *) bank, (void *)op);
+ getOrAddGNode (adj, NULL, bank); // adds the node if it does not exist yet
+ //fprintf (stderr, "%s:%d: adding %s with hash %u in bank %u\n", __FUNCTION__, __LINE__, op, hash, bank);
+ } else {
+ //fprintf (stderr, "%s:%d: found %s with hash %u in bank %u\n", __FUNCTION__, __LINE__, op, hash, bank);
+ } // if
+
+ assert (bank >= 0);
+
+ return bank;
+}
+
+/*--------------------------------------------------------------------*/
+/* isBanksel - check whether the given pCode is a BANKSEL instruction */
+/*--------------------------------------------------------------------*/
+int isBanksel (pCode *pc)
+{
+ if (!pc) return 0;
+
+ if (isPCI(pc) && (PCI(pc)->op == POC_BANKSEL || PCI(pc)->op == POC_MOVLB)) {
+ // BANKSEL <variablename> or MOVLB <banknr>
+ //fprintf (stderr, "%s:%d: BANKSEL found: %s %s\n", __FUNCTION__, __LINE__, PCAD(pc)->directive, PCAD(pc)->arg);
+ return 1;
+ }
+
+ // check for inline assembler BANKSELs
+ if (isPCAD(pc) && PCAD(pc)->directive && (STRCASECMP(PCAD(pc)->directive,"BANKSEL") == 0 ||
+ STRCASECMP(PCAD(pc)->directive,"MOVLB") == 0)) {
+ //fprintf (stderr, "%s:%d: BANKSEL found: %s %s\n", __FUNCTION__, __LINE__, PCAD(pc)->directive, PCAD(pc)->arg);
+ return 1;
+ }
+
+ // assume pc is no BANKSEL instruction
+ return 0;
+}
+
+/*---------------------------------------------------------------------------------*/
+/* invalidatesBSR - check whether the pCodeInstruction passed in modifies the BSR */
+/* This method can not guarantee to find all modifications of the */
+/* BSR (e.g. via INDirection registers) but covers all compiler */
+/* generated plus some cases. */
+/*---------------------------------------------------------------------------------*/
+int invalidatesBSR(pCode *pc)
+{
+ // assembler directives invalidate BSR (well, they might, we don't know)
+ if (isPCAD(pc)) return 1;
+
+ // only ASMDIRs and pCodeInstructions can invalidate BSR
+ if (!isPCI(pc)) return 0;
+
+ // we have a pCodeInstruction
+
+ // check for BSR modifying instructions
+ switch (PCI(pc)->op) {
+ case POC_CALL:
+ case POC_RCALL:
+ case POC_MOVLB:
+ case POC_RETFIE: // might be used as CALL replacement
+ case POC_RETLW: // might be used as CALL replacement
+ case POC_RETURN: // might be used as CALL replacement
+ case POC_BANKSEL:
+ return 1;
+ break;
+
+ default: // other instruction do not change BSR unless BSR is an explicit operand!
+ // TODO: check for BSR as an explicit operand (e.g. INCF BSR,F), which should be rather unlikely...!
+ break;
+ } // switch
+
+ // no change of BSR possible/probable
+ return 0;
+}
+
+/*------------------------------------------------------------*/
+/* getBankFromBanksel - return the pseudo bank nr assigned to */
+/* the symbol referenced in this BANKSEL */
+/*------------------------------------------------------------*/
+pseudoBankNr getBankFromBanksel (pCode *pc)
+{
+ char *sym;
+ int data = (int)NULL;
+
+ if (!pc) return INVALID_BANK;
+
+ if (isPCAD(pc) && PCAD(pc)->directive) {
+ if (STRCASECMP(PCAD(pc)->directive,"BANKSEL") == 0) {
+ // get symbolname from PCAD(pc)->arg
+ //fprintf (stderr, "%s:%d: BANKSEL found: %s %s\n", __FUNCTION__, __LINE__, PCAD(pc)->directive, PCAD(pc)->arg);
+ sym = PCAD(pc)->arg;
+ data = getPseudoBankNrFromOperand (sym);
+ //fprintf (stderr, "symbol: %s, data=%i\n", sym, data);
+ } else if (STRCASECMP(PCAD(pc)->directive,"MOVLB")) {
+ // get (literal) bank number from PCAD(pc)->arg
+ fprintf (stderr, "%s:%d: MOVLB found: %s %s\n", __FUNCTION__, __LINE__, PCAD(pc)->directive, PCAD(pc)->arg);
+ assert (0 && "not yet implemented - turn off banksel optimization for now");
+ }
+ } else if (isPCI(pc)) {
+ if (PCI(pc)->op == POC_BANKSEL) {
+ // get symbolname from PCI(pc)->pcop->name (?)
+ //fprintf (stderr, "%s:%d: BANKSEL found: %s %s\n", __FUNCTION__, __LINE__, PCI(pc)->mnemonic, PCI(pc)->pcop->name);
+ sym = PCI(pc)->pcop->name;
+ data = getPseudoBankNrFromOperand (sym);
+ //fprintf (stderr, "symbol: %s, data=%i\n", sym, data);
+ } else if (PCI(pc)->op == POC_MOVLB) {
+ // get (literal) bank number from PCI(pc)->pcop->name
+ fprintf (stderr, "%s:%d: MOVLB found: %s %s\n", __FUNCTION__, __LINE__, PCI(pc)->mnemonic, PCI(pc)->pcop->name);
+ assert (0 && "not yet implemented - turn off banksel optimization for now");
+ }
+ }
+
+ if (data == 0)
+ // no assigned bank could be found
+ return UNKNOWN_BANK;
+ else
+ return data;
+}
+
+/*------------------------------------------------------------------------------*/
+/* getEffectiveBank - resolves the currently assigned effective pseudo bank nr */
+/*------------------------------------------------------------------------------*/
+pseudoBankNr getEffectiveBank (pseudoBankNr bank)
+{
+ pseudoBank *data;
+
+ if (bank < FIRST_PSEUDO_BANK_NR) return bank;
+
+ do {
+ //fprintf (stderr, "%s:%d: bank=%d\n", __FUNCTION__, __LINE__, bank);
+ data = (pseudoBank *) hTabFindByKey (coerce, bank % coerce->size, (void *) bank, &comparePtr);
+ if (data) {
+ if (data->bank != bank)
+ bank = data->bank;
+ else
+ data = NULL;
+ }
+ } while (data);
+
+ //fprintf (stderr, "%s:%d: effective bank=%d\n", __FUNCTION__, __LINE__, bank);
+ return bank;
+}
+
+/*------------------------------------------------------------------*/
+/* attachBsrInfo2pBlock - create a look-up table as to which pseudo */
+/* bank is selected at a given pCode */
+/*------------------------------------------------------------------*/
+
+/* Create a graph with pseudo banks as its nodes and switches between
+ * these as edges (with the edge weight representing the absolute
+ * number of BANKSELs from one to the other).
+ * Removes redundand BANKSELs instead iff mod == 1.
+ * BANKSELs update the pseudo BSR, labels invalidate the current BSR
+ * value (setting it to 0=UNNKOWN), (R)CALLs also invalidate the
+ * pseudo BSR.
+ * TODO: check ALL instructions operands if they modify BSR directly...
+ *
+ * pb - the pBlock to annotate
+ * mod - select either graph creation (0) or BANKSEL removal (1)
+ */
+unsigned int attachBsrInfo2pBlock (pBlock *pb, int mod)
+{
+ pCode *pc, *pc_next;
+ unsigned int prevBSR = UNKNOWN_BANK, pseudoBSR = UNKNOWN_BANK;
+ int isBankselect = 0;
+ unsigned int banksels=0;
+
+ if (!pb) return 0;
+
+ pc = pic16_findNextInstruction(pb->pcHead);
+ while (pc) {
+ isBankselect = isBanksel (pc);
+ pc_next = pic16_findNextInstruction (pc->next);
+
+ if (!hasNoLabel (pc)) {
+ // we don't know our predecessors -- assume different BSRs
+ prevBSR = UNKNOWN_BANK;
+ pseudoBSR = UNKNOWN_BANK;
+ //fprintf (stderr, "invalidated by label at "); pc->print (stderr, pc);
+ } // if
+
+ // check if this is a BANKSEL instruction
+ if (isBankselect) {
+ pseudoBSR = getEffectiveBank (getBankFromBanksel(pc));
+ //fprintf (stderr, "BANKSEL via "); pc->print (stderr, pc);
+ if (mod) {
+ if (prevBSR == pseudoBSR && pseudoBSR >= 0) {
+ //fprintf (stderr, "removing redundant "); pc->print (stderr, pc);
+ if (1 || pic16_pcode_verbose) pic16_pCodeInsertAfter (pc->prev, pic16_newpCodeCharP("removed redundant BANKSEL"));
+ pic16_unlinkpCode (pc);
+ banksels++;
+ }
+ } else {
+ addGEdge2 (getOrAddGNode (adj, NULL, prevBSR), getOrAddGNode (adj, NULL, pseudoBSR), 1, 0);
+ banksels++;
+ }
+ } // if
+
+ if (!isBankselect && invalidatesBSR(pc)) {
+ // check if this instruction invalidates the pseudoBSR
+ pseudoBSR = UNKNOWN_BANK;
+ //fprintf (stderr, "invalidated via "); pc->print (stderr, pc);
+ } // if
+
+ prevBSR = pseudoBSR;
+ pc = pc_next;
+ } // while
+
+ return banksels;
+}
+
+/*------------------------------------------------------------------------------------*/
+/* assignToSameBank - returns 0 on success or an error code */
+/* 1 - common bank would be too large */
+/* 2 - assignment to fixed (absolute) bank not performed */
+/* */
+/* This functions assumes that unsplittable operands are already assigned to the same */
+/* bank (e.g. all objects being referenced as (SYMBOL + offset) must be in the same */
+/* bank so that we can make sure the bytes are laid out sequentially in memory) */
+/* TODO: Symbols with an abslute address must be handled specially! */
+/*------------------------------------------------------------------------------------*/
+int assignToSameBank (int bank0, int bank1, int doAbs)
+{
+ int eff0, eff1, dummy;
+ pseudoBank *pbank0, *pbank1;
+ hashtItem *hitem;
+
+ eff0 = getEffectiveBank (bank0);
+ eff1 = getEffectiveBank (bank1);
+
+ //fprintf (stderr, "%s:%d: bank0=%d/%d, bank1=%d/%d, doAbs=%d\n", __FUNCTION__, __LINE__, bank0, eff0, bank1, eff1, doAbs);
+
+ // nothing to do if already same bank
+ if (eff0 == eff1) return 0;
+
+ if (!doAbs && (eff0 < FIRST_PSEUDO_BANK_NR || eff1 < FIRST_PSEUDO_BANK_NR))
+ return 2;
+
+ // ensure eff0 < eff1
+ if (eff0 > eff1) {
+ // swap eff0 and eff1
+ dummy = eff0;
+ eff0 = eff1;
+ eff1 = dummy;
+ dummy = bank0;
+ bank0 = bank1;
+ bank1 = dummy;
+ } // if
+
+ // now assign bank eff1 to bank eff0
+ pbank0 = (pseudoBank *) hTabFindByKey (coerce, eff0 % coerce->size, (void *)((char*)0+eff0), &comparePtr);
+ if (!pbank0) {
+ pbank0 = Safe_calloc (1, sizeof (pseudoBank));
+ pbank0->bank = eff0;
+ pbank0->size = 1;
+ pbank0->ref = 1;
+ hTabAddItemLong (&coerce, eff0 % coerce->size, (void *)((char*)0+eff0), (void *) pbank0);
+ } // if
+
+ pbank1 = NULL;
+ hitem = hTabSearch (coerce, eff1 % coerce->size);
+ while (hitem && hitem->pkey != (void *)((char*)0+eff1))
+ hitem = hitem->next;
+
+ if (hitem) pbank1 = (pseudoBank *) hitem->item;
+
+#if 0
+ fprintf (stderr, "bank #%d/%d & bank #%d/%d --> bank #%d: %u (%s & %s)\n", bank0, eff0, bank1, eff1,
+ pbank0->bank, pbank0->size,
+ getSymFromBank (eff0), getSymFromBank (eff1));
+#endif
+
+ if (pbank1) {
+ if (pbank0->size + pbank1->size > MAX_COMMON_BANK_SIZE) {
+#if 0
+ fprintf (stderr, "bank #%d: %u, bank #%d: %u --> bank #%d': %u > %u (%s,%s)\n",
+ pbank0->bank, pbank0->size, pbank1->bank, pbank1->size,
+ pbank0->bank, pbank0->size + pbank1->size, MAX_COMMON_BANK_SIZE,
+ getSymFromBank (pbank0->bank), getSymFromBank (pbank1->bank));
+#endif
+ return 1;
+ } // if
+ pbank0->size += pbank1->size;
+ pbank1->ref--;
+ if (pbank1->ref == 0) Safe_free (pbank1);
+ } else {
+ pbank0->size++;
+ } // if
+
+ if (hitem)
+ hitem->item = pbank0;
+ else
+ hTabAddItemLong (&coerce, eff1 % coerce->size, (void *)((char*)0+eff1), (void *) pbank0);
+ pbank0->ref++;
+
+ //fprintf (stderr, "%s:%d: leaving.\n", __FUNCTION__, __LINE__);
+
+ return 0;
+}
+
+/*----------------------------------------------------------------*/
+/* mergeGraphNodes - combines two nodes into one and modifies all */
+/* edges to and from the nodes accordingly */
+/* This method needs complete backedges, i.e. if (A,B) is an edge */
+/* then also (B,A) must be an edge (possibly with weight 0). */
+/*----------------------------------------------------------------*/
+void mergeGraphNodes (GraphNode *node1, GraphNode *node2)
+{
+ GraphEdge *edge, *backedge, *nextedge;
+ GraphNode *node;
+ int backweight;
+
+ assert (node1 && node2);
+ assert (node1 != node2);
+
+ // add all edges starting at node2 to node1
+ edge = node2->edge;
+ while (edge) {
+ nextedge = edge->next;
+ node = edge->node;
+ backedge = getGEdge (node, node2);
+ if (backedge)
+ backweight = backedge->weight;
+ else
+ backweight = 0;
+ // insert edges (node1,node) and (node,node1)
+ addGEdge2 (node1, node, edge->weight, backweight);
+ // remove edges (node, node2) and (node2, node)
+ remGEdge (node2, node);
+ remGEdge (node, node2);
+ edge = nextedge;
+ } // while
+
+ // now node2 should not be referenced by any other GraphNode...
+ //remGNode (adj, node2->data, node2->hash);
+}
+
+/*----------------------------------------------------------------*/
+/* showGraph - dump the current BANKSEL graph as a node/edge list */
+/*----------------------------------------------------------------*/
+void showGraph (Graph *g)
+{
+ GraphNode *node;
+ GraphEdge *edge;
+ pseudoBankNr bankNr;
+ pseudoBank *pbank;
+ unsigned int size;
+
+ node = g->node;
+ while (node) {
+ edge = node->edge;
+ bankNr = getEffectiveBank (node->hash);
+ assert (bankNr >= 0);
+ pbank = (pseudoBank *) hTabFindByKey (coerce, bankNr % coerce->size, (void *) bankNr, &comparePtr);
+ if (pbank) {
+ bankNr = pbank->bank;
+ size = pbank->size;
+ } else {
+ size = 1;
+ }
+
+ fprintf (stderr, "edges from %s (bank %u, size %u) to:\n", getSymFromBank (node->hash), bankNr, size);
+
+ while (edge) {
+ if (edge->weight > 0)
+ fprintf (stderr, " %4u x %s\n", edge->weight, getSymFromBank (edge->node->hash));
+ edge = edge->next;
+ } // while (edge)
+ node = node->next;
+ } // while (node)
+}
+
+/*---------------------------------------------------------------*/
+/* pic16_OptimizeBanksel - remove redundant BANKSEL instructions */
+/*---------------------------------------------------------------*/
+void pic16_OptimizeBanksel ()
+{
+ GraphNode *node, *node1, *node1next;
+
+#if 0
+ // needed for more effective bank assignment (needs adjusted pic16_emit_usection())
+ GraphEdge *edge, *backedge;
+ GraphEdge *max;
+ int maxWeight, weight, mergeMore, absMaxWeight;
+ pseudoBankNr curr0, curr1;
+#endif
+ pseudoBank *pbank;
+ pseudoBankNr bankNr;
+ char *base_symbol0, *base_symbol1;
+ int len0, len1;
+ pBlock *pb;
+ set *set;
+ regs *reg;
+ unsigned int bankselsTotal = 0, bankselsRemoved = 0;
+
+ //fprintf (stderr, "%s:%s:%d: entered.\n", __FILE__, __FUNCTION__, __LINE__);
+
+ if (!the_pFile || !the_pFile->pbHead) return;
+
+ adj = newGraph (NULL);
+ sym2bank = newHashTable ( 255 );
+ bank2sym = newHashTable ( 255 );
+ coerce = newHashTable ( 255 );
+
+ // create graph of BANKSEL relationships (node = operands, edge (A,B) iff BANKSEL B follows BANKSEL A)
+ for (pb = the_pFile->pbHead; pb; pb = pb->next) {
+ bankselsTotal += attachBsrInfo2pBlock (pb, 0);
+ } // for pb
+
+#if 1
+ // assign symbols with absolute addresses to their respective bank nrs
+ set = pic16_fix_udata;
+ for (reg = setFirstItem (set); reg; reg = setNextItem (set)) {
+ bankNr = reg->address >> 8;
+ node = getOrAddGNode (adj, NULL, bankNr);
+ bankNr = (pseudoBankNr) getEffectiveBank (getPseudoBankNrFromOperand(reg->name));
+ assignToSameBank (node->hash, bankNr, 1);
+
+ assert (bankNr >= 0);
+ pbank = (pseudoBank *) hTabFindByKey (coerce, bankNr % coerce->size, (void *) bankNr, &comparePtr);
+ if (!pbank) {
+ pbank = Safe_calloc (1, sizeof (pseudoBank));
+ pbank->bank = reg->address >> 8; //FIXED_BANK;
+ pbank->size = 1;
+ pbank->ref = 1;
+ hTabAddItemLong (&coerce, bankNr % coerce->size, (void *) bankNr, pbank);
+ } else {
+ assert (pbank->bank == (reg->address >> 8));
+ pbank->bank = reg->address >> 8; //FIXED_BANK;
+ }
+ //fprintf (stderr, "ABS: %s (%d bytes) at %x in bank %u\n", reg->name, reg->size, reg->address, bankNr);
+ } // for reg
+#endif
+
+#if 1
+ // assign operands referring to the same symbol (which is not given an absolute address) to the same bank
+ //fprintf (stderr, "assign operands with the same symbol to the same bank\n");
+ node = adj->node;
+ while (node) {
+ if (node->hash < 0) { node = node->next; continue; }
+ base_symbol0 = getSymbolFromOperand (getSymFromBank (getEffectiveBank(node->hash)), &len0);
+ node1 = node->next;
+ while (node1) {
+ if (node1->hash < 0) { node1 = node1->next; continue; }
+ node1next = node1->next;
+ base_symbol1 = getSymbolFromOperand (getSymFromBank (getEffectiveBank (node1->hash)), &len1);
+ if (len0 == len1 && len0 > 0 && strncmp (base_symbol0, base_symbol1, len0) == 0) {
+ // TODO: check for symbols with absolute addresses -- these might be placed across bank boundaries!
+ //fprintf (stderr, "merging %s and %s\n", getSymFromBank (getEffectiveBank(node->hash)), getSymFromBank (getEffectiveBank(node1->hash)));
+ if (assignToSameBank (node->hash, node1->hash, 0)) {
+ fprintf (stderr, "%s(%d) == %s(%d)\n", base_symbol0, len0, base_symbol1, len1);
+ assert (0 && "Could not assign a symbol to a bank!");
+ }
+ mergeGraphNodes (node, node1);
+ /*
+ if (node->hash < node1->hash)
+ mergeGraphNodes (node, node1);
+ else
+ mergeGraphNodes (node1, node); // this removes node so node->next will fail...
+ */
+ } // if
+ node1 = node1next;
+ } // while (node1)
+ node = node->next;
+ } // while (node)
+#endif
+
+#if 0
+ // >>> THIS ALSO NEEDS AN UPDATED pic16_emit_usection() TO REFLECT THE BANK ASSIGNMENTS <<<
+ // assign tightly coupled operands to the same (pseudo) bank
+ //fprintf (stderr, "assign tightly coupled operands to the same bank\n");
+ mergeMore = 1;
+ absMaxWeight = 0;
+ while (mergeMore) {
+ node = adj->node;
+ max = NULL;
+ maxWeight = 0;
+ while (node) {
+ curr0 = getEffectiveBank (node->hash);
+ if (curr0 < 0) { node = node->next; continue; }
+ edge = node->edge;
+ while (edge) {
+ assert (edge->src == node);
+ backedge = getGEdge (edge->node, edge->src);
+ weight = edge->weight + (backedge ? backedge->weight : 0);
+ curr1 = getEffectiveBank (edge->node->hash);
+ if (curr1 < 0) { edge = edge->next; continue; }
+
+ // merging is only useful if the items are not assigned to the same bank already...
+ if (curr0 != curr1 && weight > maxWeight) {
+ if (maxWeight > absMaxWeight) absMaxWeight = maxWeight;
+ maxWeight = weight;
+ max = edge;
+ } // if
+ edge = edge->next;
+ } // while
+ node = node->next;
+ } // while
+
+ if (maxWeight > 0) {
+#if 0
+ fprintf (stderr, "%s:%d: merging (%4u) %d(%s) and %d(%s)\n", __FUNCTION__, __LINE__, maxWeight,
+ max->src->hash, getSymFromBank (max->src->hash),
+ max->node->hash, getSymFromBank (max->node->hash));
+#endif
+
+ node = getGNode (adj, max->src->data, max->src->hash);
+ node1 = getGNode (adj, max->node->data, max->node->hash);
+
+ if (0 == assignToSameBank (max->src->hash, max->node->hash, 0)) {
+ if (max->src->hash < max->node->hash)
+ mergeGraphNodes (node, node1);
+ else
+ mergeGraphNodes (node1, node);
+ } else {
+ remGEdge (node, node1);
+ remGEdge (node1, node);
+ //mergeMore = 0;
+ }
+
+ } else {
+ mergeMore = 0;
+ }
+ } // while
+#endif
+
+#if 1
+ // remove redundant BANKSELs
+ //fprintf (stderr, "removing redundant BANKSELs\n");
+ for (pb = the_pFile->pbHead; pb; pb = pb->next) {
+ bankselsRemoved += attachBsrInfo2pBlock (pb, 1);
+ } // for pb
+#endif
+
+#if 0
+ fprintf (stderr, "display graph\n");
+ showGraph ();
+#endif
+
+ deleteGraph (adj);
+ //fprintf (stderr, "%s:%s:%d: leaving, %u/%u BANKSELs removed...\n", __FILE__, __FUNCTION__, __LINE__, bankselsRemoved, bankselsTotal);
+}
+
+/*** END of stuff belonging to the BANKSEL optimization ***/
+
+
+
+/*** BEGIN of helpers for pCode dataflow optimizations ***/
+
+typedef unsigned int symbol_t;
+typedef unsigned int valnum_t;
+//typedef unsigned int hash_t;
+
+#ifndef INT_TO_PTR
+#define INT_TO_PTR(x) (((char *) 0) + (x))
+#endif
+
+#ifndef PTR_TO_INT
+#define PTR_TO_INT(x) (((char *)(x)) - ((char *) 0))
+#endif
+
+static int pic16_regIsLocal (regs *r);
+static int pic16_safepCodeRemove (pCode *pc, char *comment);
+
+/* statistics */
+static unsigned int pic16_df_removed_pcodes = 0;
+static unsigned int pic16_df_saved_bytes = 0;
+static unsigned int df_findall_sameflow = 0;
+static unsigned int df_findall_otherflow = 0;
+static unsigned int df_findall_in_vals = 0;
+
+static void pic16_df_stats () {
+ return;
+ if (pic16_debug_verbose || pic16_pcode_verbose) {
+ fprintf (stderr, "PIC16: dataflow analysis removed %u instructions (%u bytes)\n", pic16_df_removed_pcodes, pic16_df_saved_bytes);
+ fprintf (stderr, "findAll: same flow %u (%u in_vals), other flow %u\n", df_findall_sameflow, df_findall_in_vals, df_findall_otherflow);
+ //pic16_df_removed_pcodes = pic16_df_saved_bytes = 0;
+ }
+}
+
+/* Remove a pCode iff possible:
+ * - previous pCode is no SKIP
+ * - pc has no label
+ * Returns 1 iff the pCode has been removed, 0 otherwise. */
+static int pic16_safepCodeUnlink (pCode *pc, char *comment) {
+ pCode *pcprev, *pcnext;
+ char buf[256], *total=NULL;
+ int len;
+
+ if (!comment) comment = "=DF= pCode removed by pic16_safepCodeUnlink";
+
+ pcprev = pic16_findPrevInstruction (pc->prev);
+ pcnext = pic16_findNextInstruction (pc->next);
+
+ /* move labels to next instruction (if possible) */
+ if (PCI(pc)->label && !pcnext) return 0;
+
+ /* if this is a SKIP with side-effects -- do not remove */
+ /* XXX: might try to replace this one with the side-effect only version */
+ if (isPCI_SKIP(pc)
+ && ((PCI(pc)->outCond & (PCC_REGISTER | PCC_W)) != 0))
+ {
+ pCode *newpc;
+ switch (PCI(pc)->op)
+ {
+ case POC_INCFSZ:
+ case POC_INFSNZ:
+ newpc = pic16_newpCode(POC_INCF, pic16_pCodeOpCopy( PCI(pc)->pcop ) );
+ pic16_pCodeReplace( pc, newpc );
+ return 1;
+ break;
+ case POC_INCFSZW:
+ newpc = pic16_newpCode(POC_INCFW, pic16_pCodeOpCopy( PCI(pc)->pcop ) );
+ pic16_pCodeReplace( pc, newpc );
+ return 1;
+ break;
+ case POC_DECFSZ:
+ case POC_DCFSNZ:
+ newpc = pic16_newpCode(POC_INCF, pic16_pCodeOpCopy( PCI(pc)->pcop ) );
+ pic16_pCodeReplace( pc, newpc );
+ return 1;
+ break;
+ case POC_DECFSZW:
+ newpc = pic16_newpCode(POC_INCF, pic16_pCodeOpCopy( PCI(pc)->pcop ) );
+ pic16_pCodeReplace( pc, newpc );
+ return 1;
+ break;
+ default:
+ return 0;
+ }
+ return 0;
+ }
+
+ /* if previous instruction is a skip -- do not remove */
+ if (pcprev && isPCI_SKIP(pcprev)) {
+ if (!pic16_safepCodeUnlink (pcprev, "=DF= removed now unused SKIP")) {
+ /* preceeding SKIP could not be removed -- keep this instruction! */
+ return 0;
+ }
+ }
+
+ if (PCI(pc)->label) {
+ //fprintf (stderr, "%s: moving label(s)\n", __FUNCTION__);
+ //pc->print (stderr, pc);
+ PCI(pcnext)->label = pic16_pBranchAppend (PCI(pc)->label, PCI(pcnext)->label);
+ PCI(pc)->label = NULL;
+ }
+
+ /* update statistics */
+ pic16_df_removed_pcodes++;
+ if (isPCI(pc)) pic16_df_saved_bytes += PCI(pc)->isize;
+
+ /* remove the pCode */
+ pic16_pCode2str (buf, 256, pc);
+ //fprintf (stderr, "%s: removing pCode: %s\n", __FUNCTION__, buf);
+ if (0 || pic16_debug_verbose || pic16_pcode_verbose) {
+ len = strlen (buf) + strlen (comment) + 10;
+ total = (char *) Safe_malloc (len);
+ SNPRINTF (total, len, "%s: %s", comment, buf);
+ pic16_pCodeInsertAfter (pc, pic16_newpCodeCharP(total));
+ Safe_free (total);
+ }
+
+ /* actually unlink it from the pBlock -- also remove from to/from lists */
+ pic16_pCodeUnlink (pc);
+
+ /* remove the pCode -- release registers */
+ pc->destruct (pc);
+
+ /* report success */
+ return 1;
+}
+
+
+/* ======================================================================== */
+/* === SYMBOL HANDLING ==================================================== */
+/* ======================================================================== */
+
+static hTab *map_strToSym = NULL; /** (char *) --> symbol_t */
+static hTab *map_symToStr = NULL; /** symbol_t -> (char *) */
+static symbol_t nextSymbol = 0x2000; /** next symbol_t assigned to the next generated symbol */
+
+/** Calculate a hash for a given string.
+ * If len == 0 the string is assumed to be NUL terminated. */
+static hash_t symbolHash (const char *str, unsigned int len) {
+ hash_t hash = 0;
+ if (!len) {
+ while (*str) {
+ hash = (hash << 2) ^ *str;
+ str++;
+ } // while
+ } else {
+ while (len--) {
+ hash = (hash << 2) ^ *str;
+ str++;
+ }
+ }
+ return hash;
+}
+
+/** Return 1 iff strings v1 and v2 are identical. */
+static int symcmp (const void *v1, const void *v2) {
+ return !strcmp ((const char *) v1, (const char *) v2);
+}
+
+/** Return 1 iff pointers v1 and v2 are identical. */
+static int ptrcmp (const void *v1, const void *v2) {
+ return (v1 == v2);
+}
+
+enum { SPO_WREG=0x1000,
+ SPO_STATUS,
+ SPO_PRODL,
+ SPO_PRODH,
+ SPO_INDF0,
+ SPO_POSTDEC0,
+ SPO_POSTINC0,
+ SPO_PREINC0,
+ SPO_PLUSW0,
+ SPO_INDF1,
+ SPO_POSTDEC1,
+ SPO_POSTINC1,
+ SPO_PREINC1,
+ SPO_PLUSW1,
+ SPO_INDF2,
+ SPO_POSTDEC2,
+ SPO_POSTINC2,
+ SPO_PREINC2,
+ SPO_PLUSW2,
+ SPO_STKPTR,
+ SPO_TOSL,
+ SPO_TOSH,
+ SPO_TOSU,
+ SPO_BSR,
+ SPO_FSR0L,
+ SPO_FSR0H,
+ SPO_FSR1L,
+ SPO_FSR1H,
+ SPO_FSR2L,
+ SPO_FSR2H,
+ SPO_PCL,
+ SPO_PCLATH,
+ SPO_PCLATU,
+ SPO_TABLAT,
+ SPO_TBLPTRL,
+ SPO_TBLPTRH,
+ SPO_TBLPTRU,
+ SPO_LAST
+};
+
+/* Return the unique symbol_t for the given string. */
+static symbol_t symFromStr (const char *str) {
+ hash_t hash;
+ char *res;
+ symbol_t sym;
+
+ if (!map_symToStr) {
+ int i;
+ struct { char *name; symbol_t sym; } predefsyms[] = {
+ {"WREG", SPO_WREG},
+ {"STATUS", SPO_STATUS},
+ {"PRODL", SPO_PRODL},
+ {"PRODH", SPO_PRODH},
+ {"INDF0", SPO_INDF0},
+ {"POSTDEC0", SPO_POSTDEC0},
+ {"POSTINC0", SPO_POSTINC0},
+ {"PREINC0", SPO_PREINC0},
+ {"PLUSW0", SPO_PLUSW0},
+ {"INDF1", SPO_INDF1},
+ {"POSTDEC1", SPO_POSTDEC1},
+ {"POSTINC1", SPO_POSTINC1},
+ {"PREINC1", SPO_PREINC1},
+ {"PLUSW1", SPO_PLUSW1},
+ {"INDF2", SPO_INDF2},
+ {"POSTDEC2", SPO_POSTDEC2},
+ {"POSTINC2", SPO_POSTINC2},
+ {"PREINC2", SPO_PREINC2},
+ {"PLUSW2", SPO_PLUSW2},
+ {"STKPTR", SPO_STKPTR},
+ {"TOSL", SPO_TOSL},
+ {"TOSH", SPO_TOSH},
+ {"TOSU", SPO_TOSU},
+ {"BSR", SPO_BSR},
+ {"FSR0L", SPO_FSR0L},
+ {"FSR0H", SPO_FSR0H},
+ {"FSR1L", SPO_FSR1L},
+ {"FSR1H", SPO_FSR1H},
+ {"FSR2L", SPO_FSR2L},
+ {"FSR2H", SPO_FSR2H},
+ {"PCL", SPO_PCL},
+ {"PCLATH", SPO_PCLATH},
+ {"PCLATU", SPO_PCLATU},
+ {"TABLAT", SPO_TABLAT},
+ {"TBLPTRL", SPO_TBLPTRL},
+ {"TBLPTRH", SPO_TBLPTRH},
+ {"TBLPTRU", SPO_TBLPTRU},
+ {NULL, 0}
+ };
+
+ map_strToSym = newHashTable (128);
+ map_symToStr = newHashTable (128);
+
+ for (i=0; predefsyms[i].name; i++) {
+ char *name;
+
+ /* enter new symbol */
+ sym = predefsyms[i].sym;
+ name = predefsyms[i].name;
+ res = Safe_strdup (name);
+ hash = symbolHash (name, 0);
+
+ hTabAddItemLong (&map_strToSym, hash, res, INT_TO_PTR(sym));
+ hTabAddItemLong (&map_symToStr, sym % map_symToStr->size, INT_TO_PTR(sym), res);
+ } // for i
+ }
+
+ hash = symbolHash (str, 0) % map_strToSym->size;
+
+ /* find symbol in table */
+ sym = PTR_TO_INT(hTabFindByKey (map_strToSym, hash, str, &symcmp));
+ if (sym) {
+ //fprintf (stderr, "found symbol %x for %s\n", sym, str);
+ return sym;
+ }
+
+ /* enter new symbol */
+ sym = nextSymbol++;
+ res = Safe_strdup (str);
+
+ hTabAddItemLong (&map_strToSym, hash, res, INT_TO_PTR(sym));
+ hTabAddItemLong (&map_symToStr, sym % map_symToStr->size, INT_TO_PTR(sym), res);
+
+ //fprintf (stderr, "created symbol %x for %s\n", sym, res);
+
+ return sym;
+}
+
+#if 1
+static const char *strFromSym (symbol_t sym) {
+ return (const char *) hTabFindByKey (map_symToStr, sym % map_symToStr->size, INT_TO_PTR(sym), &ptrcmp);
+}
+#endif
+
+/* ======================================================================== */
+/* === DEFINITION MAP HANDLING ============================================ */
+/* ======================================================================== */
+
+/* A defmap provides information about which symbol is defined by which pCode.
+ * The most recent definitions are prepended to the list, so that the most
+ * recent definition can be found by forward scanning the list.
+ * pc2: MOVFF r0x00, r0x01
+ * pc1: INCF r0x01
+ * head --> ("r0x01",pc1,42) --> ("STATUS",pc1,44) --> ("r0x01",pc2,28) --> NULL
+ *
+ * We attach one defmap to each flow object, and each pCode will occur at
+ * least once in its flow's defmap (maybe defining the 0 symbol). This can be
+ * used to find definitions for a pCode in its own defmap that precede pCode.
+ */
+
+typedef struct defmap_s {
+ symbol_t sym; /** symbol this item refers to */
+ union {
+ struct {
+ unsigned int in_mask:8; /** mask leaving in accessed bits */
+ unsigned int mask:8; /** mask leaving in modified bits (if isWrite) */
+ int isRead:1; /** sym/mask is read */
+ int isWrite:1; /** sym/mask is written */
+ } access;
+ int accessmethod;
+ } acc;
+ pCode *pc; /** pCode this symbol is refrenced at */
+ valnum_t in_val; /** valnum_t of symbol's previous value (the one read at pc) */
+ valnum_t val; /** new unique number for this value (if isWrite) */
+ struct defmap_s *prev, *next; /** link to previous an next definition */
+} defmap_t;
+
+static defmap_t *defmap_free = NULL; /** list of unused defmaps */
+static int defmap_free_count = 0; /** number of released defmap items */
+
+/* Returns a defmap_t with the specified data; this will be the new list head.
+ * next - pointer to the current list head */
+static defmap_t *newDefmap (symbol_t sym, int in_mask, int mask, int isRead, int isWrite, pCode *pc, valnum_t val, defmap_t *next) {
+ defmap_t *map;
+
+ if (defmap_free) {
+ map = defmap_free;
+ defmap_free = map->next;
+ --defmap_free_count;
+ } else {
+ map = (defmap_t *) Safe_calloc (1, sizeof (defmap_t));
+ }
+ map->sym = sym;
+ map->acc.access.in_mask = (isRead ? (in_mask ? in_mask : 0xFF) : 0x00);
+ map->acc.access.mask = (isWrite ? (mask ? mask : 0xFF) : 0x00);
+ map->acc.access.isRead = (isRead != 0);
+ map->acc.access.isWrite = (isWrite != 0);
+ map->pc = pc;
+ map->in_val = 0;
+ map->val = (isWrite ? val : 0);
+ map->prev = NULL;
+ map->next = next;
+ if (next) next->prev = map;
+
+ return map;
+}
+
+/* Returns a copy of the single defmap item. */
+static defmap_t *copyDefmap (defmap_t *map) {
+ defmap_t *res = (defmap_t *) Safe_malloc (sizeof (defmap_t));
+ memcpy (res, map, sizeof (defmap_t));
+ res->next = NULL;
+ res->prev = NULL;
+ return res;
+}
+
+/* Insert a defmap item after the specified one. */
+static int defmapInsertAfter (defmap_t *ref, defmap_t *newItem) {
+ if (!ref || !newItem) return 1;
+
+ newItem->next = ref->next;
+ newItem->prev = ref;
+ ref->next = newItem;
+ if (newItem->next) newItem->next->prev = newItem;
+
+ return 0;
+}
+
+/* Check whether item (or an identical one) is already in the chain and add it if neccessary.
+ * item is copied before insertion into chain and therefore left untouched.
+ * Returns 1 iff the item has been inserted into the list, 0 otherwise. */
+static int defmapAddCopyIfNew (defmap_t **head, defmap_t *item) {
+ defmap_t *dummy;
+ dummy = *head;
+ while (dummy && (dummy->sym != item->sym
+ || dummy->pc != item->pc
+ || dummy->acc.accessmethod != item->acc.accessmethod
+ || dummy->val != item->val
+ || dummy->in_val != item->in_val)) {
+ dummy = dummy->next;
+ } // while
+
+ /* item already present? */
+ if (dummy) return 0;
+
+ /* otherwise: insert copy of item */
+ dummy = copyDefmap (item);
+ dummy->next = *head;
+ if (*head) (*head)->prev = dummy;
+ *head = dummy;
+
+ return 1;
+}
+
+/* Releases a defmap. This also removes the map from its chain -- update the head manually! */
+static void deleteDefmap (defmap_t *map) {
+ if (!map) return;
+
+ /* unlink from chain -- fails for the first item (head is not updated!) */
+ if (map->next) map->next->prev = map->prev;
+ if (map->prev) map->prev->next = map->next;
+
+ /* clear map */
+ memset (map, 0, sizeof (defmap_t));
+
+ /* save for future use */
+ map->next = defmap_free;
+ defmap_free = map;
+ ++defmap_free_count;
+}
+
+/* Release all defmaps referenced from map. */
+static void deleteDefmapChain (defmap_t **_map) {
+ defmap_t *map, *next;
+
+ if (!_map) return;
+
+ map = *_map;
+
+ /* find list head */
+ while (map && map->prev) map = map->prev;
+
+ /* delete all items */
+ while (map) {
+ next = map->next;
+ deleteDefmap (map);
+ map = next;
+ } // while
+
+ *_map = NULL;
+}
+
+/* Free all defmap items. */
+static void freeDefmap (defmap_t **_map) {
+ defmap_t *next;
+ defmap_t *map;
+
+ if (!_map) return;
+
+ map = (*_map);
+
+ /* find list head */
+ while (map->prev) map = map->prev;
+
+ /* release all items */
+ while (map) {
+ next = map->next;
+ Safe_free (map);
+ map = next;
+ }
+
+ (*_map) = NULL;
+}
+
+/* Returns the most recent definition for the given symbol preceeding pc.
+ * If no definition is found, NULL is returned.
+ * If pc == NULL the whole list is scanned. */
+static defmap_t *defmapFindDef (defmap_t *map, symbol_t sym, pCode *pc) {
+ defmap_t *curr = map;
+
+ if (pc) {
+ /* skip all definitions up to pc */
+ while (curr && (curr->pc != pc)) curr = curr->next;
+
+ /* pc not in the list -- scan the whole list for definitions */
+ if (!curr) {
+ fprintf (stderr, "pc %p not found in defmap -- scanning whole list for symbol '%s'\n", pc, strFromSym (sym));
+ curr = map;
+ } else {
+ /* skip all definitions performed by pc */
+ while (curr && (curr->pc == pc)) curr = curr->next;
+ }
+ } // if (pc)
+
+ /* find definition for sym */
+ while (curr && (!curr->acc.access.isWrite || (curr->sym != sym))) {
+ curr = curr->next;
+ }
+
+ return curr;
+}
+
+#if 0
+/* Returns the first use (read) of the given symbol AFTER pc.
+ * If no such use is found, NULL is returned.
+ * If pc == NULL the whole list is scanned. */
+static defmap_t *defmapFindUse (defmap_t *map, symbol_t sym, pCode *pc) {
+ defmap_t *curr = map, *prev = NULL;
+
+ if (pc) {
+ /* skip all definitions up to pc */
+ while (curr && (curr->pc != pc)) { prev = curr; curr = curr->next; }
+
+ /* pc not in the list -- scan the whole list for definitions */
+ if (!curr) {
+ //fprintf (stderr, "pc %p not found in defmap -- scanning whole list for symbol '%s'\n", pc, strFromSym (sym));
+ curr = prev;
+ }
+ } else {
+ /* find end of list */
+ while (curr && curr->next) curr = curr->next;
+ } // if (pc)
+
+ /* find use of sym (scan list backwards) */
+ while (curr && (!curr->acc.access.isRead || (curr->sym != sym))) curr = curr->prev;
+
+ return curr;
+}
+#endif
+
+/* Return the defmap entry for sym AT pc.
+ * If none is found, NULL is returned.
+ * If more than one entry is found an assertion is triggered. */
+static defmap_t *defmapCurr (defmap_t *map, symbol_t sym, pCode *pc) {
+ defmap_t *res = NULL;
+
+ /* find entries for pc */
+ while (map && map->pc != pc) map = map->next;
+
+ /* find first entry for sym @ pc */
+ while (map && map->pc == pc && map->sym != sym) map = map->next;
+
+ /* no entry found */
+ if (!map) return NULL;
+
+ /* check for more entries */
+ res = map;
+ map = map->next;
+ while (map && map->pc == pc) {
+ /* more than one entry for sym @ pc found? */
+ assert (map->sym != sym);
+ map = map->next;
+ }
+
+ /* return single entry for sym @ pc */
+ return res;
+}
+
+/* Modifies the definition of sym at pCode to newval.
+ * Returns 0 on success, 1 if no definition of sym in pc has been found.
+ */
+static int defmapUpdate (defmap_t *map, symbol_t sym, pCode *pc, valnum_t newval) {
+ defmap_t *m = map;
+
+ /* find definitions of pc */
+ while (m && m->pc != pc) m = m->next;
+
+ /* find definition of sym at pc */
+ while (m && m->pc == pc && (!m->acc.access.isWrite || (m->sym != sym))) m = m->next;
+
+ /* no definition found */
+ if (!m) return 1;
+
+ /* redefine */
+ m->val = newval;
+
+ /* update following uses of sym */
+ while (m && m->pc == pc) m = m->prev;
+ while (m) {
+ if (m->sym == sym) {
+ m->in_val = newval;
+ if (m->acc.access.isWrite) m = NULL;
+ } // if
+ if (m) m = m->prev;
+ } // while
+
+ return 0;
+}
+
+/* ======================================================================== */
+/* === STACK ROUTINES ===================================================== */
+/* ======================================================================== */
+
+typedef struct stack_s {
+ void *data;
+ struct stack_s *next;
+} stackitem_t;
+
+typedef stackitem_t *dynstack_t;
+static stackitem_t *free_stackitems = NULL;
+
+/* Create a stack with one item. */
+static dynstack_t *newStack () {
+ dynstack_t *s = (dynstack_t *) Safe_malloc (sizeof (dynstack_t));
+ *s = NULL;
+ return s;
+}
+
+/* Remove a stack -- its items are only marked free. */
+static void deleteStack (dynstack_t *s) {
+ stackitem_t *i;
+
+ while (*s) {
+ i = *s;
+ *s = (*s)->next;
+ i->next = free_stackitems;
+ free_stackitems = i;
+ } // while
+ Safe_free (s);
+}
+
+/* Release all stackitems. */
+static void releaseStack () {
+ stackitem_t *i;
+
+ while (free_stackitems) {
+ i = free_stackitems->next;
+ Safe_free(free_stackitems);
+ free_stackitems = i;
+ } // while
+}
+
+static void stackPush (dynstack_t *stack, void *data) {
+ stackitem_t *i;
+
+ if (free_stackitems) {
+ i = free_stackitems;
+ free_stackitems = free_stackitems->next;
+ } else {
+ i = (stackitem_t *) Safe_calloc (1, sizeof (stackitem_t));
+ }
+ i->data = data;
+ i->next = *stack;
+ *stack = i;
+}
+
+static void *stackPop (dynstack_t *stack) {
+ void *data;
+ stackitem_t *i;
+
+ if (stack && *stack) {
+ data = (*stack)->data;
+ i = *stack;
+ *stack = (*stack)->next;
+ i->next = free_stackitems;
+ free_stackitems = i;
+ return data;
+ } else {
+ return NULL;
+ }
+}
+
+#if 0
+static int stackContains (dynstack_t *s, void *data) {
+ stackitem_t *i;
+ if (!s) return 0;
+ i = *s;
+ while (i) {
+ if (i->data == data) return 1;
+ i = i->next;
+ } // while
+
+ /* not found */
+ return 0;
+}
+#endif
+
+static int stackIsEmpty (dynstack_t *s) {
+ return (*s == NULL);
+}
+
+
+typedef struct {
+ pCodeFlow *flow;
+ defmap_t *lastdef;
+} state_t;
+
+static state_t *newState (pCodeFlow *flow, defmap_t *lastdef) {
+ state_t *s = (state_t *) Safe_calloc (1, sizeof (state_t));
+ s->flow = flow;
+ s->lastdef = lastdef;
+ return s;
+}
+
+static void deleteState (state_t *s) {
+ Safe_free (s);
+}
+
+static int stateIsNew (state_t *state, dynstack_t *todo, dynstack_t *done) {
+ stackitem_t *i;
+
+ /* scan working list for state */
+ if (todo) {
+ i = *todo;
+ while (i) {
+ /* is i == state? -- state not new */
+ if ((((state_t *) (i->data))->flow == state->flow) && (((state_t *) (i->data))->lastdef == state->lastdef)) return 0;
+ i = i->next;
+ } // while
+ }
+
+ if (done) {
+ i = *done;
+ while (i) {
+ /* is i == state? -- state not new */
+ if ((((state_t *) (i->data))->flow == state->flow) && (((state_t *) (i->data))->lastdef == state->lastdef)) return 0;
+ i = i->next;
+ } // while
+ }
+
+ /* not found -- state is new */
+ return 1;
+}
+
+static inline valnum_t newValnum ();
+
+const char *pic16_pBlockGetFunctionName (pBlock *pb) {
+ pCode *pc;
+
+ if (!pb) return "<unknown function>";
+
+ pc = pic16_findNextpCode (pb->pcHead, PC_FUNCTION);
+ if (pc && isPCF(pc)) return PCF(pc)->fname;
+ else return "<unknown function>";
+}
+
+static defmap_t *pic16_pBlockAddInval (pBlock *pb, symbol_t sym) {
+ defmap_t *map;
+ pCodeFlow *pcfl;
+
+ pcfl = PCI(pic16_findNextInstruction (pb->pcHead))->pcflow;
+
+ /* find initial value (assigning pc == NULL) */
+ map = PCFL(pcfl)->in_vals;
+ while (map && map->sym != sym) map = map->next;
+
+ /* initial value already present? */
+ if (map) {
+ //fprintf (stderr, "found init value for sym %s (%x): %u\n", strFromSym(sym), sym, map->val);
+ return map;
+ }
+
+ /* create a new initial value */
+ map = newDefmap (sym, 0x00, 0xff, 0, 1, NULL, newValnum(), PCFL(pcfl)->in_vals);
+ PCFL(pcfl)->in_vals = map;
+ //fprintf (stderr, "Created init value for sym %s (%x): %u\n", strFromSym(sym), sym, map->val);
+ return map;
+
+#if 0
+ /* insert map as last item in pcfl's defmap */
+ if (!prev) prev = PCFL(pcfl)->defmap;
+ if (!prev) {
+ PCFL(pcfl)->defmap = map;
+ } else {
+ while (prev->next) prev = prev->next;
+ prev->next = map;
+ map->prev = prev;
+ }
+
+ return map;
+#endif
+}
+
+/* Find all reaching definitions for sym at pc.
+ * A new (!) list of definitions is returned.
+ * Returns the number of reaching definitions found.
+ * The defining defmap entries are returned in *chain.
+ */
+static int defmapFindAll (symbol_t sym, pCode *pc, defmap_t **chain) {
+ defmap_t *map;
+ defmap_t *res;
+
+ pCodeFlow *curr;
+ pCodeFlowLink *succ;
+ state_t *state;
+ dynstack_t *todo; /** stack of state_t */
+ dynstack_t *done; /** stack of state_t */
+
+ int firstState, n_defs;
+
+ assert (pc && isPCI(pc) && PCI(pc)->pcflow);
+ assert (chain);
+
+ /* initialize return list */
+ *chain = NULL;
+
+ /* wildcard symbol? */
+ if (!sym) return 0;
+
+ //fprintf (stderr, "Searching definition of sym %s(%x) @ pc %p(%p)\n", strFromSym(sym), sym, pc, pc->pb);
+
+ map = PCI(pc)->pcflow->defmap;
+
+ res = defmapFindDef (map, sym, pc);
+ //if (res) fprintf (stderr, "found def in own flow @ pc %p\n", res->pc);
+
+#define USE_PRECALCED_INVALS 1
+#if USE_PRECALCED_INVALS
+ if (!res && PCI(pc)->pcflow->in_vals) {
+ res = defmapFindDef (PCI(pc)->pcflow->in_vals, sym, NULL);
+ if (res) {
+ //fprintf (stderr, "found def in init values\n");
+ df_findall_in_vals++;
+ }
+ }
+#endif
+
+ if (res) {
+ // found a single definition (in pc's flow)
+ //fprintf (stderr, "unique definition for %s @ %p found @ %p (val: %x)\n", strFromSym(sym), pc, res->pc, res->val);
+ defmapAddCopyIfNew (chain, res);
+ df_findall_sameflow++;
+ return 1;
+ }
+
+#if USE_PRECALCED_INVALS
+ else {
+ defmapAddCopyIfNew (chain, pic16_pBlockAddInval (pc->pb, sym));
+ return 1;
+ }
+
+#endif
+
+#define FORWARD_FLOW_ANALYSIS 1
+#if defined FORWARD_FLOW_ANALYSIS && FORWARD_FLOW_ANALYSIS
+ /* no definition found in pc's flow preceeding pc */
+ todo = newStack ();
+ done = newStack ();
+ n_defs = 0; firstState = 1;
+ stackPush (todo, newState (PCI(pic16_findNextInstruction(pc->pb->pcHead))->pcflow, res));
+
+ while (!stackIsEmpty (todo)) {
+ state = (state_t *) stackPop (todo);
+ stackPush (done, state);
+ curr = state->flow;
+ res = state->lastdef;
+ //fprintf (stderr, "searching def of sym %s in pcFlow %p (lastdef %x @ %p)\n", strFromSym(sym), curr, res ? res->val : 0, res ? res->pc : NULL);
+
+ /* there are no definitions BEFORE pc in pc's flow (see above) */
+ if (curr == PCI(pc)->pcflow) {
+ if (!res) {
+ //fprintf (stderr, "symbol %s(%x) might be used uninitialized at %p\n", strFromSym(sym), sym, pc);
+ res = pic16_pBlockAddInval (pc->pb, sym);
+ if (defmapAddCopyIfNew (chain, res)) n_defs++;
+ res = NULL;
+ } else {
+ //fprintf (stderr, "reaching definition for %s @ %p found @ %p (val: %x)\n", strFromSym(sym), pc, res->pc, res->val);
+ if (defmapAddCopyIfNew (chain, res)) n_defs++;
+ }
+ }
+
+ /* save last definition of sym in this flow as initial def in successors */
+ res = defmapFindDef (curr->defmap, sym, NULL);
+ if (!res) res = state->lastdef;
+
+ /* add successors to working list */
+ state = newState (NULL, NULL);
+ succ = (pCodeFlowLink *) setFirstItem (curr->to);
+ while (succ) {
+ //fprintf (stderr, " %p --> %p with %x\n", curr, succ->pcflow, res ? res->val : 0);
+ state->flow = succ->pcflow;
+ state->lastdef = res;
+ if (stateIsNew (state, todo, done)) {
+ stackPush (todo, state);
+ state = newState (NULL, NULL);
+ } // if
+ succ = (pCodeFlowLink *) setNextItem (curr->to);
+ } // while
+ deleteState (state);
+ } // while
+
+#else // !FORWARD_FLOW_ANALYSIS
+
+ /* no definition found in pc's flow preceeding pc */
+ todo = newStack ();
+ done = newStack ();
+ n_defs = 0; firstState = 1;
+ stackPush (todo, newState (PCI(pc)->pcflow, res));
+
+ while (!stackIsEmpty (todo)) {
+ state = (state_t *) stackPop (todo);
+ curr = state->flow;
+
+ if (firstState) {
+ firstState = 0;
+ /* only check predecessor flows */
+ } else {
+ /* get (last) definition of sym in this flow */
+ res = defmapFindDef (curr->defmap, sym, NULL);
+ }
+
+ if (res) {
+ /* definition found */
+ //fprintf (stderr, "reaching definition for %s @ %p found @ %p (val: %x)\n", strFromSym(sym), pc, res->pc, res->val);
+ if (defmapAddCopyIfNew (chain, res)) n_defs++;
+ } else {
+ /* no definition found -- check predecessor flows */
+ state = newState (NULL, NULL);
+ succ = (pCodeFlowLink *) setFirstItem (curr->from);
+
+ /* if no flow predecessor available -- sym might be uninitialized */
+ if (!succ) {
+ //fprintf (stder, "sym %s might be used uninitialized at %p\n", strFromSym (sym), pc);
+ res = newDefmap (sym, 0xff, 0, 1, NULL, 0, *chain);
+ if (defmapAddCopyIfNew (chain, res)) n_defs++;
+ deleteDefmap (res); res = NULL;
+ }
+
+ while (succ) {
+ //fprintf (stderr, " %p --> %p with %x\n", curr, succ->pcflow, res ? res->val : 0);
+ state->flow = succ->pcflow;
+ state->lastdef = res;
+ if (stateIsNew (state, todo, done)) {
+ stackPush (todo, state);
+ state = newState (NULL, NULL);
+ } // if
+ succ = (pCodeFlowLink *) setNextItem (curr->from);
+ } // while
+ deleteState (state);
+ }
+ } // while
+
+#endif
+
+ /* clean up done stack */
+ while (!stackIsEmpty(done)) {
+ deleteState ((state_t *) stackPop (done));
+ } // while
+ deleteStack (done);
+
+ /* return number of items in result set */
+ if (n_defs == 0) {
+ //fprintf (stderr, "sym %s might be used uninitialized at %p\n", strFromSym (sym), pc);
+ } else if (n_defs == 1) {
+ assert (*chain);
+ //fprintf (stderr, "sym %s at %p always defined as %x @ %p\n", strFromSym(sym), pc, (*chain)->val, (*chain)->pc);
+ } else if (n_defs > 0) {
+ //fprintf (stderr, "%u definitions for sym %s at %p found:\n", n_defs, strFromSym(sym), pc);
+#if 0
+ res = *chain;
+ while (res) {
+ fprintf (stderr, " as %4x @ %p\n", res->val, res->pc);
+ res = res->next;
+ } // while
+#endif
+ }
+ //fprintf (stderr, "%u definitions for sym %s at %p found\n", n_defs, strFromSym(sym), pc);
+ df_findall_otherflow++;
+ return n_defs;
+}
+
+/* ======================================================================== */
+/* === VALUE NUMBER HANDLING ============================================== */
+/* ======================================================================== */
+
+static valnum_t nextValnum = 0x1000;
+static hTab *map_symToValnum = NULL;
+
+/** Return a new value number. */
+static inline valnum_t newValnum () {
+ return (nextValnum += 4);
+}
+
+static valnum_t valnumFromStr (const char *str) {
+ symbol_t sym;
+ valnum_t val;
+ void *res;
+
+ sym = symFromStr (str);
+
+ if (!map_symToValnum) {
+ map_symToValnum = newHashTable (128);
+ } // if
+
+ /* literal already known? */
+ res = hTabFindByKey (map_symToValnum, sym % map_symToValnum->size, INT_TO_PTR(sym), &ptrcmp);
+
+ /* return existing valnum */
+ if (res) return (valnum_t) PTR_TO_INT(res);
+
+ /* create new valnum */
+ val = newValnum();
+ hTabAddItemLong (&map_symToValnum, sym % map_symToValnum->size, INT_TO_PTR(sym), INT_TO_PTR(val));
+ //fprintf (stderr, "NEW VALNUM %x for symbol %s\n", val, str);
+ return val;
+}
+
+/* Create a valnum for a literal. */
+static valnum_t valnumFromLit (unsigned int lit) {
+ return ((valnum_t) 0x100 + (lit & 0x0FF));
+}
+
+/* Return the (positive) literal value represented by val
+ * or -1 iff val is no known literal's valnum. */
+static int litFromValnum (valnum_t val) {
+ if (val >= 0x100 && val < 0x200) {
+ /* valnum is a (known) literal */
+ return val & 0x00FF;
+ } else {
+ /* valnum is not a known literal */
+ return -1;
+ }
+}
+
+#if 0
+/* Sanity check - all flows in a block must be reachable from initial flow. */
+static int verifyAllFlowsReachable (pBlock *pb) {
+ set *reached;
+ set *flowInBlock;
+ set *checked;
+ pCode *pc;
+ pCodeFlow *pcfl;
+ pCodeFlowLink *succ;
+ int res;
+
+ //fprintf (stderr, "%s - started for %s.\n" ,__FUNCTION__, pic16_pBlockGetFunctionName (pb));
+
+ reached = NULL;
+ flowInBlock = NULL;
+ checked = NULL;
+ /* mark initial flow as reached (and "not needs to be reached") */
+ pc = pic16_findNextpCode (pb->pcHead, PC_FLOW);
+ assert (pc);
+ addSetHead (&reached, pc);
+ addSetHead (&checked, pc);
+
+ /* mark all further flows in block as "need to be reached" */
+ pc = pb->pcHead;
+ do {
+ if (isPCI(pc)) addSetIfnotP (&flowInBlock, PCI(pc)->pcflow);
+ pc = pic16_findNextInstruction (pc->next);
+ } while (pc);
+
+ while (reached && (pcfl = (pCodeFlow *)indexSet (reached, 0)) != NULL) {
+ /* mark as reached and "not need to be reached" */
+ deleteSetItem (&reached, pcfl);
+ //fprintf (stderr, "%s - checking %p\n" ,__FUNCTION__, pcfl);
+
+ /* flow is no longer considered unreachable */
+ deleteSetItem (&flowInBlock, pcfl);
+
+ for (succ = setFirstItem (pcfl->to); succ; succ = setNextItem (pcfl->to)) {
+ if (!isinSet (checked, succ->pcflow)) {
+ /* flow has never been reached before */
+ addSetHead (&reached, succ->pcflow);
+ addSetHead (&checked, succ->pcflow);
+ } // if
+ } // for succ
+ } // while
+
+ //fprintf (stderr, "%s - finished\n", __FUNCTION__);
+
+ /* by now every flow should have been reached
+ * --> flowInBlock should be empty */
+ res = (flowInBlock == NULL);
+
+#if 1
+ if (flowInBlock) {
+ fprintf (stderr, "not all flows reached in %s:\n", pic16_pBlockGetFunctionName (pb));
+ while (flowInBlock) {
+ pcfl = indexSet (flowInBlock, 0);
+ fprintf (stderr, "not reached: flow %p\n", pcfl);
+ deleteSetItem (&flowInBlock, pcfl);
+ } // while
+ }
+#endif
+
+ /* clean up */
+ deleteSet (&reached);
+ deleteSet (&flowInBlock);
+ deleteSet (&checked);
+
+ /* if we reached every flow, succ is NULL by now... */
+ //assert (res); // will fire on unreachable code...
+ return (res);
+}
+#endif
+
+/* Checks a flow for accesses to sym AFTER pc.
+ *
+ * Returns -1 if the symbol is read in this flow (before redefinition),
+ * returns 0 if the symbol is redefined in this flow or
+ * returns a mask [0x01 -- 0xFF] indicating the bits still alive after this flow.
+ */
+int pic16_isAliveInFlow (symbol_t sym, int mask, pCodeFlow *pcfl, pCode *pc) {
+ defmap_t *map, *mappc;
+
+ /* find pc or start of definitions */
+ map = pcfl->defmap;
+ while (map && (map->pc != pc) && map->next) map = map->next;
+ /* if we found pc -- ignore it */
+ while (map && map->pc == pc) map = map->prev;
+
+ /* scan list backwards (first definition first) */
+ while (map && mask) {
+// if (map->sym == sym) {
+ //fprintf (stderr, "%s: accessing sym %s in pc %p/map %p\n", __FUNCTION__, strFromSym(sym), map->pc, map);
+ mappc = map;
+ /* scan list for reads at this pc first */
+ while (map && map->pc == mappc->pc) {
+ /* is the symbol (partially) read? */
+ if ((map->sym == sym) && (map->acc.access.isRead && ((map->acc.access.in_mask & mask) != 0))) {
+ //if (sym != SPO_STATUS) fprintf (stderr, "%s: symbol %s read at pc %p\n", __FUNCTION__, strFromSym (sym), map->pc);
+ return -1;
+ }
+ map = map->prev;
+ } // while
+ map = mappc;
+
+ while (map && map->pc == mappc->pc) {
+ /* honor (partial) redefinitions of sym */
+ if ((map->sym == sym) && (map->acc.access.isWrite)) {
+ mask &= ~map->acc.access.mask;
+ //if (sym != SPO_STATUS) fprintf (stderr, "%s: symbol %s redefined at pc %p, alive mask: %x\n", __FUNCTION__, strFromSym (sym), map->pc, mask);
+ }
+ map = map->prev;
+ } // while
+// } // if
+ /* map already points to the first defmap for the next pCode */
+ //map = mappc->prev;
+ } // while
+
+ /* the symbol is not completely redefined in this flow and not accessed -- symbol
+ * is still alive; return the appropriate mask of alive bits */
+ return mask;
+}
+
+/* Check whether a symbol is alive (AFTER pc). */
+static int pic16_isAlive (symbol_t sym, pCode *pc) {
+ int mask, visit;
+ defmap_t *map;
+ dynstack_t *todo, *done;
+ state_t *state;
+ pCodeFlow *pcfl;
+ pCodeFlowLink *succ;
+
+ mask = 0x00ff;
+
+ assert (isPCI(pc));
+ pcfl = PCI(pc)->pcflow;
+ map = pcfl->defmap;
+
+ todo = newStack ();
+ done = newStack ();
+
+ state = newState (pcfl, (defmap_t *) INT_TO_PTR(mask));
+ stackPush (todo, state);
+ visit = 0;
+
+ while (!stackIsEmpty (todo)) {
+ state = (state_t *) stackPop (todo);
+ pcfl = state->flow;
+ mask = PTR_TO_INT(state->lastdef);
+ if (visit) stackPush (done, state); else deleteState(state);
+ //fprintf (stderr, "%s: checking flow %p for symbol %s (%x)/%x\n", __FUNCTION__, pcfl, strFromSym(sym), sym, mask);
+ // make sure flows like A(i1,i2,pc,i3,...) --> A with pc reading and writing sym are handled correctly!
+ mask = pic16_isAliveInFlow (sym, mask, pcfl, visit == 0 ? pc : NULL);
+ visit++;
+
+ /* symbol is redefined in flow before use -- not alive in this flow (maybe in others?) */
+ if (mask == 0) continue;
+
+ /* symbol is (partially) read before redefinition in flow */
+ if (mask == -1) break;
+
+ /* symbol is neither read nor completely redefined -- check successor flows */
+ for (succ = setFirstItem(pcfl->to); succ; succ = setNextItem (pcfl->to)) {
+ state = newState (succ->pcflow, (defmap_t *) INT_TO_PTR(mask));
+ if (stateIsNew (state, todo, done)) {
+ stackPush (todo, state);
+ } else {
+ deleteState (state);
+ }
+ } // for
+ } // while
+
+ while (!stackIsEmpty (todo)) deleteState ((state_t *) stackPop (todo));
+ while (!stackIsEmpty (done)) deleteState ((state_t *) stackPop (done));
+
+ /* symbol is read in at least one flow -- is alive */
+ if (mask == -1) return 1;
+
+ /* symbol is read in no flow */
+ return 0;
+}
+
+/* Returns whether access to the given symbol has side effects. */
+static int pic16_symIsSpecial (symbol_t sym) {
+ //fprintf (stderr, "%s: sym=%x\n", __FUNCTION__, sym);
+ switch (sym) {
+ case SPO_INDF0:
+ case SPO_PLUSW0:
+ case SPO_POSTINC0:
+ case SPO_POSTDEC0:
+ case SPO_PREINC0:
+ case SPO_INDF1:
+ case SPO_PLUSW1:
+ case SPO_POSTINC1:
+ case SPO_POSTDEC1:
+ case SPO_PREINC1:
+ case SPO_INDF2:
+ case SPO_PLUSW2:
+ case SPO_POSTINC2:
+ case SPO_POSTDEC2:
+ case SPO_PREINC2:
+ case SPO_PCL:
+ return 1;
+ default:
+ /* no special effects known */
+ return 0;
+ } // switch
+
+ return 0;
+}
+
+/* Check whether a register should be considered local (to the current function) or not. */
+static int pic16_regIsLocal (regs *r) {
+ symbol_t sym;
+ if (r) {
+ if (r->type == REG_TMP) return 1;
+
+ sym = symFromStr (r->name);
+ switch (sym) {
+ case SPO_WREG:
+ case SPO_FSR0L: // used in ptrget/ptrput
+ case SPO_FSR0H: // ... as well
+ case SPO_FSR1L: // used as stack pointer... (so not really local but shared among function calls)
+ case SPO_FSR1H: // ... as well
+ case SPO_FSR2L: // used as frame pointer
+ case SPO_FSR2H: // ... as well
+ case SPO_PRODL: // used to return values from functions
+ case SPO_PRODH: // ... as well
+ /* these registers (and some more...) are considered local */
+ return 1;
+ break;
+ default:
+ /* for unknown regs: check is marked local, leave if not */
+ if (r->isLocal) {
+ return 1;
+ } else {
+ //fprintf (stderr, "%s: non-local reg used: %s\n", __FUNCTION__, r->name);
+ return 0;
+ }
+ } // switch
+ } // if
+
+ /* if in doubt, assume non-local... */
+ return 0;
+}
+
+/* Check all symbols touched by pc whether their newly assigned values are read.
+ * Returns 0 if no symbol is used later on, 1 otherwise. */
+static int pic16_pCodeIsAlive (pCode *pc) {
+ pCodeInstruction *pci;
+ defmap_t *map, *lastpc;
+ regs *checkreg;
+
+ /* we can only handle PCIs */
+ if (!isPCI(pc)) return 1;
+
+ //pc->print (stderr, pc);
+
+ pci = PCI(pc);
+ assert (pci && pci->pcflow && pci->pcflow->defmap);
+
+ /* NEVER remove instructions with implicit side effects */
+ switch (pci->op) {
+ case POC_TBLRD:
+ case POC_TBLRD_POSTINC: /* modify TBLPTRx */
+ case POC_TBLRD_POSTDEC:
+ case POC_TBLRD_PREINC:
+ case POC_TBLWT: /* modify program memory */
+ case POC_TBLWT_POSTINC: /* modify TBLPTRx */
+ case POC_TBLWT_POSTDEC:
+ case POC_TBLWT_PREINC:
+ case POC_CLRWDT: /* clear watchdog timer */
+ case POC_PUSH: /* should be safe to remove though... */
+ case POC_POP: /* should be safe to remove though... */
+ case POC_CALL:
+ case POC_RCALL:
+ case POC_RETFIE:
+ case POC_RETURN:
+ //fprintf (stderr, "%s: instruction with implicit side effects not removed: %s\n", __FUNCTION__, pci->mnemonic);
+ return 1;
+
+ default:
+ /* no special instruction */
+ break;
+ } // switch
+
+ /* prevent us from removing assignments to non-local variables */
+ checkreg = NULL;
+ if (PCI(pc)->outCond & PCC_REGISTER) checkreg = pic16_getRegFromInstruction (pc);
+ else if (PCI(pc)->outCond & PCC_REGISTER2) checkreg = pic16_getRegFromInstruction2(pc);
+
+ if ((PCI(pc)->outCond & (PCC_REGISTER | PCC_REGISTER2)) && !checkreg) {
+ /* assignment to DIRECT operand like "BSF (_global + 1),6" */
+ //fprintf (stderr, "%s: assignment to register detected, but register not available!\n", __FUNCTION__);
+ //pc->print (stderr, pc);
+ return 1;
+ }
+ if ((PCI(pc)->outCond & (PCC_REGISTER | PCC_REGISTER2)) && !pic16_regIsLocal (checkreg)) {
+ //fprintf (stderr, "%s: dest-reg not local %s\n", __FUNCTION__, checkreg ? checkreg->name : "<unknown>");
+ return 1;
+ }
+
+#if 1
+ /* OVERKILL: prevent us from removing reads from non-local variables
+ * THIS IS HERE TO AVOID PROBLEMS WITH VOLATILE OPERANDS ONLY!
+ * Once registers get a "isVolatile" field this might be handled more efficiently... */
+ checkreg = NULL;
+ if (PCI(pc)->inCond & PCC_REGISTER) checkreg = pic16_getRegFromInstruction (pc);
+ else if (PCI(pc)->inCond & PCC_REGISTER2) checkreg = pic16_getRegFromInstruction2(pc);
+
+ if ((PCI(pc)->inCond & (PCC_REGISTER | PCC_REGISTER2)) && !checkreg) {
+ /* read from DIRECT operand like "BTFSS (_global + 1),6" -- might be volatile */
+ //fprintf (stderr, "%s: read from register detected, but register not available!\n", __FUNCTION__);
+ //pc->print (stderr, pc);
+ return 1;
+ }
+ if ((PCI(pc)->inCond & (PCC_REGISTER | PCC_REGISTER2)) && !pic16_regIsLocal (checkreg)) {
+ //fprintf (stderr, "%s: src-reg not local: %s\n", __FUNCTION__, checkreg ? checkreg->name : "<unknown>");
+ return 1;
+ }
+#endif
+
+ /* now check that the defined symbols are not used */
+ map = pci->pcflow->defmap;
+
+ /* find items for pc */
+ while (map && map->pc != pc) map = map->next;
+
+ /* no entries found? something is fishy with DF analysis... -- play safe */
+ if (!map) {
+ if (pic16_pcode_verbose) {
+ fprintf (stderr, "%s: defmap not found\n", __FUNCTION__);
+ }
+ return 1;
+ }
+
+ /* remember first item assigned to pc for later use */
+ lastpc = map;
+
+ /* check all symbols being modified by pc */
+ while (map && map->pc == pc) {
+ if (map->sym == 0) { map = map->next; continue; }
+
+ /* keep pc if it references special symbols (like POSTDEC0) */
+#if 0
+ {
+ char buf[256];
+ pic16_pCode2str (buf, 256, pc);
+ fprintf (stderr, "%s: checking for sym %x(%s) at pc %p (%s)\n", __FUNCTION__, map->sym, strFromSym (map->sym), pc, buf);
+ }
+#endif
+ if (pic16_symIsSpecial (map->sym)) {
+ //fprintf (stderr, "%s: special sym\n", __FUNCTION__);
+ return 1;
+ }
+ if (map->acc.access.isWrite) {
+ if (pic16_isAlive (map->sym, pc)) {
+ //fprintf (stderr, "%s(%s): pCode is alive (sym %s still used)\n", __FUNCTION__, pic16_pBlockGetFunctionName (pc->pb),strFromSym (map->sym));
+ return 1;
+ }
+ }
+ map = map->next;
+ } // while
+
+ /* no use for any of the pc-assigned symbols found -- pCode is dead and can be removed */
+#if 0
+ {
+ char buf[256];
+ pic16_pCode2str (buf, 256, pc);
+ fprintf (stderr, "%s: pCode %p (%s) is dead.\n", __FUNCTION__, pc, buf);
+ }
+#endif
+ return 0;
+}
+
+/* Adds implied operands to the list.
+ * sym - operand being accessed in the pCode
+ * list - list to append the operand
+ * isRead - set to 1 iff sym is read in pCode
+ * listRead - set to 1 iff all operands being read are to be listed
+ *
+ * Returns 0 for "normal" operands, 1 for special operands.
+ */
+static int fixupSpecialOperands (symbol_t sym, int in_mask, int mask, pCode *pc, valnum_t val, defmap_t **list, int isRead, int isWrite) {
+ /* check whether accessing REG accesses other REGs as well */
+ switch (sym) {
+ case SPO_INDF0:
+ /* reads FSR0x */
+ *list = newDefmap (sym, 0xff, 0xff, 0, 0, pc, 0, *list);
+ *list = newDefmap (SPO_FSR0L, 0xff, 0xff, 1, 0, pc, 0, *list);
+ *list = newDefmap (SPO_FSR0H, 0xff, 0xff, 1, 0, pc, 0, *list);
+ break;
+
+ case SPO_PLUSW0:
+ /* reads FSR0x and WREG */
+ *list = newDefmap (SPO_WREG, 0xff, 0x00, 1, 0, pc, 0, *list);
+ *list = newDefmap (sym, 0xff, 0xff, 0, 0, pc, 0, *list);
+ *list = newDefmap (SPO_FSR0L, 0xff, 0xff, 1, 0, pc, 0, *list);
+ *list = newDefmap (SPO_FSR0H, 0xff, 0xff, 1, 0, pc, 0, *list);
+ break;
+
+ case SPO_POSTDEC0:
+ case SPO_POSTINC0:
+ case SPO_PREINC0:
+ /* reads/modifies FSR0x */
+ *list = newDefmap (sym, 0xff, 0xff, 0, 0, pc, 0, *list);
+ *list = newDefmap (SPO_FSR0L, 0xff, 0xff, 1, 1, pc, newValnum (), *list);
+ *list = newDefmap (SPO_FSR0H, 0xff, 0xff, 1, 1, pc, newValnum (), *list);
+ break;
+
+ case SPO_INDF1:
+ /* reads FSR1x */
+ *list = newDefmap (sym, 0xff, 0xff, 0, 0, pc, 0, *list);
+ *list = newDefmap (SPO_FSR1L, 0xff, 0xff, 1, 0, pc, 0, *list);
+ *list = newDefmap (SPO_FSR1H, 0xff, 0xff, 1, 0, pc, 0, *list);
+ break;
+
+ case SPO_PLUSW1:
+ /* reads FSR1x and WREG */
+ *list = newDefmap (SPO_WREG, 0xff, 0x00, 1, 0, pc, 0, *list);
+ *list = newDefmap (sym, 0xff, 0xff, 0, 0, pc, 0, *list);
+ *list = newDefmap (SPO_FSR1L, 0xff, 0xff, 1, 0, pc, 0, *list);
+ *list = newDefmap (SPO_FSR1H, 0xff, 0xff, 1, 0, pc, 0, *list);
+ break;
+
+ case SPO_POSTDEC1:
+ case SPO_POSTINC1:
+ case SPO_PREINC1:
+ /* reads/modifies FSR1x */
+ *list = newDefmap (sym, 0xff, 0xff, 0, 0, pc, 0, *list);
+ *list = newDefmap (SPO_FSR1L, 0xff, 0xff, 1, 1, pc, newValnum (), *list);
+ *list = newDefmap (SPO_FSR1H, 0xff, 0xff, 1, 1, pc, newValnum (), *list);
+ break;
+
+ case SPO_INDF2:
+ /* reads FSR2x */
+ *list = newDefmap (sym, 0xff, 0xff, 0, 0, pc, 0, *list);
+ *list = newDefmap (SPO_FSR2L, 0xff, 0xff, 1, 0, pc, 0, *list);
+ *list = newDefmap (SPO_FSR2H, 0xff, 0xff, 1, 0, pc, 0, *list);
+ break;
+
+ case SPO_PLUSW2:
+ /* reads FSR2x and WREG */
+ *list = newDefmap (SPO_WREG, 0xff, 0x00, 1, 0, pc, 0, *list);
+ *list = newDefmap (sym, 0xff, 0xff, 0, 0, pc, 0, *list);
+ *list = newDefmap (SPO_FSR2L, 0xff, 0xff, 1, 0, pc, 0, *list);
+ *list = newDefmap (SPO_FSR2H, 0xff, 0xff, 1, 0, pc, 0, *list);
+ break;
+
+ case SPO_POSTDEC2:
+ case SPO_POSTINC2:
+ case SPO_PREINC2:
+ /* reads/modifies FSR2x */
+ *list = newDefmap (sym, 0xff, 0xff, 0, 0, pc, 0, *list);
+ *list = newDefmap (SPO_FSR2L, 0xff, 0xff, 1, 1, pc, newValnum (), *list);
+ *list = newDefmap (SPO_FSR2H, 0xff, 0xff, 1, 1, pc, newValnum (), *list);
+ break;
+
+ case SPO_PCL:
+ /* modifies PCLATH and PCLATU */
+ *list = newDefmap (SPO_PCL, 0xff, 0xff, isRead, isWrite, pc, newValnum (), *list);
+ if (isRead) {
+ /* reading PCL updates PCLATx */
+ *list = newDefmap (SPO_PCLATH, 0xff, 0xff, 0, 1, pc, newValnum (), *list);
+ *list = newDefmap (SPO_PCLATU, 0xff, 0xff, 0, 1, pc, newValnum (), *list);
+ }
+ if (isWrite) {
+ /* writing PCL implicitly reads PCLATx (computed GOTO) */
+ *list = newDefmap (SPO_PCLATH, 0xff, 0xff, 1, 0, pc, 0, *list);
+ *list = newDefmap (SPO_PCLATU, 0xff, 0xff, 1, 0, pc, 0, *list);
+ }
+ break;
+
+ default:
+ *list = newDefmap (sym, in_mask, mask, isRead, isWrite, pc, val, *list);
+ /* nothing special */
+ return 0;
+ break;
+ }
+
+ /* has been a special operand */
+ return 1;
+}
+
+static symbol_t pic16_fsrsym_idx[][2] = {
+ {SPO_FSR0L, SPO_FSR0H},
+ {SPO_FSR1L, SPO_FSR1H},
+ {SPO_FSR2L, SPO_FSR2H}
+};
+
+/* Merge multiple defmap entries for the same symbol for list's pCode. */
+static void mergeDefmapSymbols (defmap_t *list) {
+ defmap_t *ref, *curr, *temp;
+
+ /* now make sure that each symbol occurs at most once per pc */
+ ref = list;
+ while (ref && (ref->pc == list->pc)) {
+ curr = ref->next;
+ while (curr && (curr->pc == list->pc)) {
+ if (curr->sym == ref->sym) {
+ //fprintf (stderr, "Merging defmap entries for symbol %s\n", strFromSym (ref->sym));
+ /* found a symbol occuring twice... merge the two */
+ if (curr->acc.access.isRead) {
+ //if (ref->acc.access.isRead) fprintf (stderr, "symbol %s was marked twice as read at pc %p\n", strFromSym (ref->sym), ref->pc);
+ ref->acc.access.isRead = 1;
+ ref->acc.access.in_mask |= curr->acc.access.in_mask;
+ }
+ if (curr->acc.access.isWrite) {
+ //if (ref->acc.access.isWrite) fprintf (stderr, "symbol %s was marked twice as written at pc %p\n", strFromSym (ref->sym), ref->pc);
+ ref->acc.access.isWrite = 1;
+ ref->acc.access.mask |= curr->acc.access.mask;
+ }
+ temp = curr;
+ curr = curr->next;
+ deleteDefmap (temp);
+ continue; // do not skip curr!
+ } // if
+ curr = curr->next;
+ } // while
+ ref = ref->next;
+ } // while
+}
+
+/** Prepend list with the reads and definitions performed by pc. */
+static defmap_t *createDefmap (pCode *pc, defmap_t *list) {
+ pCodeInstruction *pci;
+ int cond, inCond, outCond;
+ int mask = 0xff, smask;
+ int isSpecial, isSpecial2;
+ symbol_t sym, sym2;
+ char *name;
+
+ if (isPCAD(pc)) {
+ /* make sure there is at least one entry for each pc (needed by list traversal routines) */
+ /* TODO: mark this defmap node as an ASMDIR -- any values might be read/modified */
+ fprintf (stderr, "ASMDIRs not supported by data flow analysis!\n");
+ list = newDefmap (0, 0xff, 0xff, 0, 0, pc, 0, list);
+ return list;
+ }
+ assert (isPCI(pc));
+ pci = PCI(pc);
+
+ /* handle bit instructions */
+ if (pci->isBitInst) {
+ assert (pci->pcop->type == PO_GPR_BIT);
+ mask = 1U << (PCORB(PCI(pc)->pcop)->bit);
+ }
+
+ /* handle (additional) implicit arguments */
+ switch (pci->op) {
+ case POC_LFSR:
+ {
+ int lit;
+ valnum_t val;
+ lit = PCOL(pci->pcop)->lit;
+ assert (lit >= 0 && lit < 3);
+ //fprintf (stderr, "LFSR: %s // %s\n", pci->pcop->name, pic16_get_op(((pCodeOpLit2 *)(pci->pcop))->arg2, NULL, 0));
+ val = valnumFromStr (pic16_get_op(((pCodeOpLit2 *)(pci->pcop))->arg2, NULL, 0));
+ //fprintf (stderr, "LFSR lit=%u, symval=%4x\n", lit, val);
+ list = newDefmap (pic16_fsrsym_idx[lit][0], 0x00, 0xff, 0, 1, pc, val, list);
+ list = newDefmap (pic16_fsrsym_idx[lit][1], 0x00, 0xff, 0, 1, pc, val+1, list); // val+1 is guaranteed not be used as a valnum...
+ }
+ break;
+
+ case POC_MOVLB: // BSR
+ case POC_BANKSEL: // BSR
+ list = newDefmap (SPO_BSR, 0x00, 0xff, 0, 1, pc, valnumFromStr (pic16_get_op (((pCodeOpLit2 *)(pci->pcop))->arg2, NULL, 0)), list);
+ break;
+
+ case POC_MULWF: // PRODx
+ case POC_MULLW: // PRODx
+ list = newDefmap (SPO_PRODH, 0x00, 0xff, 0, 1, pc, newValnum (), list);
+ list = newDefmap (SPO_PRODL, 0x00, 0xff, 0, 1, pc, newValnum (), list);
+ break;
+
+ case POC_POP: // TOS, STKPTR
+ list = newDefmap (SPO_STKPTR, 0xff, 0xff, 1, 1, pc, newValnum (), list);
+ list = newDefmap (SPO_TOSL, 0x00, 0xff, 0, 1, pc, newValnum (), list);
+ list = newDefmap (SPO_TOSH, 0x00, 0xff, 0, 1, pc, newValnum (), list);
+ list = newDefmap (SPO_TOSU, 0x00, 0xff, 0, 1, pc, newValnum (), list);
+ break;
+
+ case POC_PUSH: // STKPTR
+ list = newDefmap (SPO_STKPTR, 0xff, 0xff, 1, 1, pc, newValnum (), list);
+ list = newDefmap (SPO_TOSL, 0xff, 0xff, 0, 1, pc, newValnum (), list);
+ list = newDefmap (SPO_TOSH, 0xff, 0xff, 0, 1, pc, newValnum (), list);
+ list = newDefmap (SPO_TOSU, 0xff, 0xff, 0, 1, pc, newValnum (), list);
+ break;
+
+ case POC_CALL: // return values (and arguments?): WREG, PRODx, FSR0L
+ case POC_RCALL: // return values (and arguments?): WREG, PRODx, FSR0L
+ list = newDefmap (SPO_WREG, 0xff, 0xff, 1, 1, pc, newValnum (), list);
+ list = newDefmap (SPO_PRODL, 0xff, 0xff, 1, 1, pc, newValnum (), list);
+ list = newDefmap (SPO_PRODH, 0xff, 0xff, 1, 1, pc, newValnum (), list);
+ list = newDefmap (SPO_FSR0L, 0xff, 0xff, 1, 1, pc, newValnum (), list);
+
+ /* needs correctly set-up stack pointer */
+ list = newDefmap (SPO_FSR1L, 0xff, 0x00, 1, 0, pc, 0, list);
+ list = newDefmap (SPO_FSR1H, 0xff, 0x00, 1, 0, pc, 0, list);
+ break;
+
+ case POC_RETLW: // return values: WREG, PRODx, FSR0L
+ /* pseudo read on (possible) return values */
+ // WREG is handled below via outCond
+ list = newDefmap (SPO_PRODL, 0xff, 0x00, 1, 0, pc, 0, list);
+ list = newDefmap (SPO_PRODH, 0xff, 0x00, 1, 0, pc, 0, list);
+ list = newDefmap (SPO_FSR0L, 0xff, 0x00, 1, 0, pc, 0, list);
+
+ /* caller's stack pointers must be restored */
+ list = newDefmap (SPO_FSR1L, 0xff, 0x00, 1, 0, pc, 0, list);
+ list = newDefmap (SPO_FSR1H, 0xff, 0x00, 1, 0, pc, 0, list);
+ list = newDefmap (SPO_FSR2L, 0xff, 0x00, 1, 0, pc, 0, list);
+ list = newDefmap (SPO_FSR2H, 0xff, 0x00, 1, 0, pc, 0, list);
+ break;
+
+ case POC_RETURN: // return values; WREG, PRODx, FSR0L
+ case POC_RETFIE: // return value: WREG, PRODx, FSR0L
+ /* pseudo read on (possible) return values */
+ list = newDefmap (SPO_WREG, 0xff, 0x00, 1, 0, pc, 0, list);
+ list = newDefmap (SPO_PRODL, 0xff, 0x00, 1, 0, pc, 0, list);
+ list = newDefmap (SPO_PRODH, 0xff, 0x00, 1, 0, pc, 0, list);
+ list = newDefmap (SPO_FSR0L, 0xff, 0x00, 1, 0, pc, 0, list);
+
+ /* caller's stack pointers must be restored */
+ list = newDefmap (SPO_FSR1L, 0xff, 0x00, 1, 0, pc, 0, list);
+ list = newDefmap (SPO_FSR1H, 0xff, 0x00, 1, 0, pc, 0, list);
+ list = newDefmap (SPO_FSR2L, 0xff, 0x00, 1, 0, pc, 0, list);
+ list = newDefmap (SPO_FSR2H, 0xff, 0x00, 1, 0, pc, 0, list);
+ break;
+
+ case POC_TBLRD:
+ list = newDefmap (SPO_TBLPTRL, 0xff, 0x00, 1, 0, pc, 0, list);
+ list = newDefmap (SPO_TBLPTRH, 0xff, 0x00, 1, 0, pc, 0, list);
+ list = newDefmap (SPO_TBLPTRU, 0xff, 0x00, 1, 0, pc, 0, list);
+ list = newDefmap (SPO_TABLAT, 0x00, 0xff, 0, 1, pc, newValnum(), list);
+ break;
+
+ case POC_TBLRD_POSTINC:
+ case POC_TBLRD_POSTDEC:
+ case POC_TBLRD_PREINC:
+ list = newDefmap (SPO_TBLPTRL, 0xff, 0xff, 1, 1, pc, newValnum(), list);
+ list = newDefmap (SPO_TBLPTRH, 0xff, 0xff, 1, 1, pc, newValnum(), list);
+ list = newDefmap (SPO_TBLPTRU, 0xff, 0xff, 1, 1, pc, newValnum(), list);
+ list = newDefmap (SPO_TABLAT, 0x00, 0xff, 0, 1, pc, newValnum(), list);
+ break;
+
+ case POC_TBLWT:
+ list = newDefmap (SPO_TBLPTRL, 0xff, 0x00, 1, 0, pc, 0, list);
+ list = newDefmap (SPO_TBLPTRH, 0xff, 0x00, 1, 0, pc, 0, list);
+ list = newDefmap (SPO_TBLPTRU, 0xff, 0x00, 1, 0, pc, 0, list);
+ list = newDefmap (SPO_TABLAT, 0xff, 0x00, 1, 0, pc, 0, list);
+ break;
+
+ case POC_TBLWT_POSTINC:
+ case POC_TBLWT_POSTDEC:
+ case POC_TBLWT_PREINC:
+ list = newDefmap (SPO_TBLPTRL, 0xff, 0xff, 1, 1, pc, newValnum(), list);
+ list = newDefmap (SPO_TBLPTRH, 0xff, 0xff, 1, 1, pc, newValnum(), list);
+ list = newDefmap (SPO_TBLPTRU, 0xff, 0xff, 1, 1, pc, newValnum(), list);
+ list = newDefmap (SPO_TABLAT, 0xff, 0x00, 1, 0, pc, 0, list);
+ break;
+
+ default:
+ /* many instruction implicitly read BSR... -- THIS IS IGNORED! */
+ break;
+ } // switch
+
+ /* handle explicit arguments */
+ inCond = pci->inCond;
+ outCond = pci->outCond;
+ cond = inCond | outCond;
+ if (cond & PCC_W) {
+ list = newDefmap (symFromStr ("WREG"), mask, mask, inCond & PCC_W, outCond & PCC_W, pc, newValnum (), list);
+ } // if
+
+ /* keep STATUS read BEFORE STATUS write in the list (still neccessary?) */
+ if (inCond & PCC_STATUS) {
+ smask = 0;
+ if (inCond & PCC_C) smask |= 1U << PIC_C_BIT;
+ if (inCond & PCC_DC) smask |= 1U << PIC_DC_BIT;
+ if (inCond & PCC_Z) smask |= 1U << PIC_Z_BIT;
+ if (inCond & PCC_OV) smask |= 1U << PIC_OV_BIT;
+ if (inCond & PCC_N) smask |= 1U << PIC_N_BIT;
+
+ list = newDefmap (symFromStr ("STATUS"), smask, 0x00, 1, 0, pc, 0, list);
+ //fprintf (stderr, "pc %p: def STATUS & %02x\n", pc, smask);
+ } // if
+
+ if (outCond & PCC_STATUS) {
+ smask = 0;
+ if (outCond & PCC_C) smask |= 1U << PIC_C_BIT;
+ if (outCond & PCC_DC) smask |= 1U << PIC_DC_BIT;
+ if (outCond & PCC_Z) smask |= 1U << PIC_Z_BIT;
+ if (outCond & PCC_OV) smask |= 1U << PIC_OV_BIT;
+ if (outCond & PCC_N) smask |= 1U << PIC_N_BIT;
+
+ list = newDefmap (symFromStr ("STATUS"), 0x00, smask, 0, 1, pc, newValnum (), list);
+ //fprintf (stderr, "pc %p: def STATUS & %02x\n", pc, smask);
+ } // if
+
+ isSpecial = isSpecial2 = 0;
+ sym = sym2 = 0;
+ if (cond & PCC_REGISTER) {
+ name = pic16_get_op (pci->pcop, NULL, 0);
+ sym = symFromStr (name);
+ isSpecial = fixupSpecialOperands (sym, mask, mask, pc, newValnum(), &list, inCond & PCC_REGISTER, outCond & PCC_REGISTER);
+ //fprintf (stderr, "pc %p: def REG %s(%x) & %02x\n", pc, name, sym, mask);
+ }
+
+ if (cond & PCC_REGISTER2) {
+ name = pic16_get_op2 (pci->pcop, NULL, 0);
+ sym2 = symFromStr (name);
+ isSpecial2 = fixupSpecialOperands (sym2, mask, mask, pc, newValnum(), &list, inCond & PCC_REGISTER2, outCond & PCC_REGISTER2);
+ //fprintf (stderr, "pc %p: def REG2 %s(%x) & %02x\n", pc, name, sym2, mask);
+ }
+
+
+ /* make sure there is at least one entry for each pc (needed by list traversal routines) */
+ list = newDefmap (0, 0x00, 0x00, 0, 0, pc, 0, list);
+
+ mergeDefmapSymbols (list);
+
+ return list;
+}
+
+#if 0
+static void printDefmap (defmap_t *map) {
+ defmap_t *curr;
+
+ curr = map;
+ fprintf (stderr, "defmap @ %p:\n", curr);
+ while (curr) {
+ fprintf (stderr, "%s%s: %4x|%4x / %02x|%02x, sym %s(%x) @ pc %p\n",
+ curr->acc.access.isRead ? "R" : " ",
+ curr->acc.access.isWrite ? "W": " ",
+ curr->in_val, curr->val,
+ curr->acc.access.in_mask, curr->acc.access.mask,
+ strFromSym(curr->sym), curr->sym,
+ curr->pc);
+ curr = curr->next;
+ } // while
+ fprintf (stderr, "<EOL>\n");
+}
+#endif
+
+/* Add "additional" definitions to uniq.
+ * This can be used to merge the in_values and the flow's defmap to create an in_value-list for the flow's successors.
+ * This can also be used to create a uniq (out)list from a flow's defmap by passing *uniq==NULL.
+ *
+ * If symbols defined in additional are not present in uniq, a definition is created.
+ * Otherwise the present definition is altered to reflect the newer assignments.
+ *
+ * flow: <uniq> --> assign1 --> assign2 --> assign3 --> ... --> <uniq'>
+ * before `------- noted in additional --------' after
+ *
+ * I assume that each symbol occurs AT MOST ONCE in uniq.
+ *
+ */
+static int defmapUpdateUniqueSym (defmap_t **uniq, defmap_t *additional) {
+ defmap_t *curr;
+ defmap_t *old;
+ int change = 0;
+
+ //fprintf (stderr, "%s: merging %p & %p\n", __FUNCTION__, *uniq, additional);
+ /* find tail of additional list (holds the first assignment) */
+ curr = additional;
+ while (curr && curr->next) curr = curr->next;
+
+ /* update uniq */
+ do {
+ /* find next assignment in additionals */
+ while (curr && !curr->acc.access.isWrite) curr = curr->prev;
+
+ if (!curr) break;
+
+ /* find item in uniq */
+ old = *uniq;
+ //printDefmap (*uniq);
+ while (old && (old->sym != curr->sym)) old = old->next;
+
+ if (old) {
+ /* definition found -- replace */
+ if (old->val != curr->val) {
+ old->val = curr->val;
+ change++;
+ } // if
+ } else {
+ /* new definition */
+ *uniq = newDefmap (curr->sym, 0x00, 0xff, 0, 1, NULL, curr->val, *uniq);
+ change++;
+ }
+
+ curr = curr->prev;
+ } while (1);
+
+ /* return 0 iff uniq remained unchanged */
+ return change;
+}
+
+/* Creates the in_value list of a flow by (iteratively) merging the out_value
+ * lists of its predecessor flows.
+ * Initially *combined should be NULL, alt_in will be copied to combined.
+ * If *combined != NULL, combined will be altered:
+ * - for symbols defined in *combined but not in alt_in,
+ * *combined is altered to 0 (value unknown, either *combined or INIT).
+ * - for symbols defined in alt_in but not in *combined,
+ * a 0 definition is created (value unknown, either INIT or alt).
+ * - for symbols defined in both, *combined is:
+ * > left unchanged if *combined->val == alt_in->val or
+ * > modified to 0 otherwise (value unknown, either alt or *combined).
+ *
+ * I assume that each symbol occurs AT MOST ONCE in each list!
+ */
+static int defmapCombineFlows (defmap_t **combined, defmap_t *alt_in, pBlock *pb) {
+ defmap_t *curr;
+ defmap_t *old;
+ int change = 0;
+ valnum_t val;
+
+ //fprintf (stderr, "%s: merging %p & %p\n", __FUNCTION__, *combined, alt_in);
+
+ if (!(*combined)) {
+ return defmapUpdateUniqueSym (combined, alt_in);
+ } // if
+
+ /* merge the two */
+ curr = alt_in;
+ while (curr) {
+ /* find symbols definition in *combined */
+ old = *combined;
+ while (old && (old->sym != curr->sym)) old = old->next;
+
+ if (old) {
+ /* definition found */
+ if (old->val && (old->val != curr->val)) {
+ old->val = 0; /* value unknown */
+ change++;
+ }
+ } else {
+ /* no definition found -- can be either INIT or alt_in's value */
+ val = pic16_pBlockAddInval (pb, curr->sym)->val;
+ *combined = newDefmap (curr->sym, 0x00, 0xff, 0, 1, NULL, (val == curr->val) ? val : 0, *combined);
+ if (val != curr->val) change++;
+ }
+
+ curr = curr->next;
+ } // while (curr)
+
+ /* update symbols from *combined that are NOT defined in alt_in -- can be either *combined's value or INIT */
+ old = *combined;
+ while (old) {
+ if (old->val != 0) {
+ /* find definition in alt_in */
+ curr = alt_in;
+ while (curr && curr->sym != old->sym) curr = curr->next;
+ if (!curr) {
+ /* symbol defined in *combined only -- can be either INIT or *combined */
+ val = pic16_pBlockAddInval (pb, old->sym)->val;
+ if (old->val != val) {
+ old->val = 0;
+ change++;
+ }
+ } // if
+ } // if
+
+ old = old->next;
+ } // while
+
+ return change;
+}
+
+static int defmapCompareUnique (defmap_t *map1, defmap_t *map2) {
+ defmap_t *curr1, *curr2;
+ symbol_t sym;
+
+ /* identical maps are equal */
+ if (map1 == map2) return 0;
+
+ if (!map1) return -1;
+ if (!map2) return 1;
+
+ //fprintf (stderr, "%s: comparing %p & %p\n", __FUNCTION__, map1, map2);
+
+ /* check length */
+ curr1 = map1;
+ curr2 = map2;
+ while (curr1 && curr2) {
+ curr1 = curr1->next;
+ curr2 = curr2->next;
+ } // while
+
+ /* one of them longer? */
+ if (curr1) return 1;
+ if (curr2) return -1;
+
+ /* both lists are of equal length -- compare (in O(n^2)) */
+ curr1 = map1;
+ while (curr1) {
+ sym = curr1->sym;
+ curr2 = map2;
+ while (curr2 && curr2->sym != sym) curr2 = curr2->next;
+ if (!curr2) return 1; // symbol not found in curr2
+ if (curr2->val != curr1->val) return 1; // values differ
+
+ /* compare next symbol */
+ curr1 = curr1->next;
+ } // while
+
+ /* no difference found */
+ return 0;
+}
+
+
+/* Prepare a list of all reaching definitions per flow.
+ * This is done using a forward dataflow analysis.
+ */
+static void createReachingDefinitions (pBlock *pb) {
+ defmap_t *out_vals, *in_vals;
+ pCode *pc;
+ pCodeFlow *pcfl;
+ pCodeFlowLink *link;
+ set *todo;
+ set *blacklist;
+
+ /* initialize out_vals to unique'fied defmaps per pCodeFlow */
+ for (pc = pic16_findNextInstruction (pb->pcHead); pc; pc = pic16_findNextInstruction (pc->next)) {
+ if (isPCFL(pc)) {
+ deleteDefmapChain (&PCFL(pc)->in_vals);
+ deleteDefmapChain (&PCFL(pc)->out_vals);
+ defmapUpdateUniqueSym (&PCFL(pc)->out_vals, PCFL(pc)->defmap);
+ } // if
+ } // for
+
+ pc = pic16_findNextInstruction (pb->pcHead);
+ todo = NULL; blacklist = NULL;
+ addSetHead (&todo, PCI(pc)->pcflow);
+
+ //fprintf (stderr, "%s: function %s()\n", __FUNCTION__, pic16_pBlockGetFunctionName (pb));
+ while (elementsInSet (todo)) {
+ //fprintf (stderr, "%u items in todo-set\n", elementsInSet (todo));
+ pcfl = PCFL(indexSet (todo, 0));
+ deleteSetItem (&todo, pcfl);
+ //fprintf (stderr, "%s: checking %p\n", __FUNCTION__, pcfl);
+ in_vals = NULL;
+ out_vals = NULL;
+
+ if (isinSet (blacklist, pcfl)) {
+ fprintf (stderr, "ignoring blacklisted flow\n");
+ continue;
+ }
+
+ /* create in_vals from predecessors out_vals */
+ link = setFirstItem (pcfl->from);
+ while (link) {
+ defmapCombineFlows (&in_vals, link->pcflow->out_vals, pb);
+ link = setNextItem (pcfl->from);
+ } // while
+
+ //printDefmap (in_vals);
+ //printDefmap (pcfl->in_vals);
+
+ if (!pcfl->in_vals || !pcfl->out_vals || defmapCompareUnique (in_vals, pcfl->in_vals)) {
+ //fprintf (stderr, "in_vals changed\n");
+ /* in_vals changed -- update out_vals */
+ deleteDefmapChain (&pcfl->in_vals);
+ pcfl->in_vals = in_vals;
+
+ /* create out_val from in_val and defmap */
+ out_vals = NULL;
+ defmapUpdateUniqueSym (&out_vals, in_vals);
+ defmapUpdateUniqueSym (&out_vals, pcfl->defmap);
+
+ /* is out_vals different from pcfl->out_vals */
+ if (!pcfl->out_vals || defmapCompareUnique (out_vals, pcfl->out_vals)) {
+ //fprintf (stderr, "out_vals changed\n");
+ deleteDefmapChain (&pcfl->out_vals);
+ pcfl->out_vals = out_vals;
+
+ if (pcfl->out_vals == NULL && pcfl->in_vals == NULL) {
+ addSet (&blacklist, pcfl);
+ } // if
+
+ /* reschedule all successors */
+ link = setFirstItem (pcfl->to);
+ while (link) {
+ //fprintf (stderr, " %p --> %p\n", pcfl, link->pcflow);
+ addSetIfnotP (&todo, link->pcflow);
+ link = setNextItem (pcfl->to);
+ } // while
+ } else {
+ deleteDefmapChain (&out_vals);
+ }// if
+ } else {
+ deleteDefmapChain (&in_vals);
+ } // if
+ } // while
+}
+
+#if 0
+static void showAllDefs (symbol_t sym, pCode *pc) {
+ defmap_t *map;
+ int count;
+
+ assert (isPCI(pc));
+ count = defmapFindAll (sym, pc, &map);
+
+ fprintf (stderr, "sym %s(%x) @ %p defined as (val@pc): ", strFromSym(sym), sym, pc);
+ while (map) {
+#if 1
+ fprintf (stderr, "(%x @ %p) ", map->val, map->pc);
+#else
+ { char buf[256];
+ pic16_pCode2str (buf, 256, map->pc);
+ fprintf (stderr, "\n (%x @ %p(%s)) ", map->val, map->pc, buf);
+#endif
+ map = map->next;
+ }
+ deleteDefmapChain (&map);
+}
+#endif
+
+/* safepCodeUnlink and remove pc from defmap. */
+static int pic16_safepCodeRemove (pCode *pc, char *comment) {
+ defmap_t *map, *next, **head;
+ int res, ispci;
+
+ ispci = isPCI(pc);
+ map = isPCI(pc) ? PCI(pc)->pcflow->defmap : NULL;
+ head = isPCI(pc) ? &PCI(pc)->pcflow->defmap : NULL;
+ res = pic16_safepCodeUnlink (pc, comment);
+
+ if (res && map) {
+ /* remove pc from defmap */
+ while (map) {
+ next = map->next;
+ if (map->pc == pc) {
+ if (!map->prev && head) *head = map->next;
+ deleteDefmap (map);
+ } // if
+ map = next;
+ }
+ }
+
+ return res;
+}
+
+void pic16_fixDefmap (pCode *pc, pCode *newpc) {
+ defmap_t *map;
+ /* This breaks the defmap chain's references to pCodes... fix it! */
+ map = PCI(pc)->pcflow->defmap;
+
+ while (map && map->pc != pc) map = map->next;
+
+ while (map && map->pc == pc) {
+ map->pc = newpc;
+ map = map->next;
+ } // while
+}
+
+/* Replace a defmap entry for sym with newsym for read accesses (isRead == 1) or
+ * write accesses (isRead == 0). */
+void defmapReplaceSymRef (pCode *pc, symbol_t sym, symbol_t newsym, int isRead) {
+ defmap_t *map, *map_start;
+ defmap_t *copy;
+ if (!isPCI(pc)) return;
+ if (sym == newsym) return;
+
+ map = PCI(pc)->pcflow->defmap;
+
+ while (map && map->pc != pc) map = map->next;
+ map_start = map;
+ while (map && map->pc == pc) {
+ if (map->sym == sym) {
+ assert ((isRead && map->acc.access.isRead) || ((!isRead) && (map->acc.access.isWrite)));
+ if (!(map->acc.access.isRead && map->acc.access.isWrite)) {
+ /* only one kind of access handled... this is easy */
+ map->sym = newsym;
+ } else {
+ /* must copy defmap entry before replacing symbol... */
+ copy = copyDefmap (map);
+ if (isRead) {
+ map->acc.access.isRead = 0;
+ copy->acc.access.isWrite = 0;
+ } else {
+ map->acc.access.isWrite = 0;
+ copy->acc.access.isRead = 0;
+ }
+ copy->sym = newsym;
+ /* insert copy into defmap chain */
+ defmapInsertAfter (map, copy);
+ }
+ }
+ map = map->next;
+ } // while
+
+ /* as this might introduce multiple defmap entries for newsym... */
+ mergeDefmapSymbols (map_start);
+}
+
+/* Assign "better" valnums to results. */
+static void assignValnums (pCode *pc) {
+ pCodeInstruction *pci;
+ pCode *newpc;
+ symbol_t sym1, sym2;
+ int cond, isSpecial1, isSpecial2, count, mask, lit;
+ defmap_t *list, *val, *oldval, *dummy;
+ regs *reg1 = NULL, *reg2 = NULL;
+ valnum_t litnum;
+
+ /* only works for pCodeInstructions... */
+ if (!isPCI(pc)) return;
+
+ pci = PCI(pc);
+ cond = pci->inCond | pci->outCond;
+ list = pci->pcflow->defmap;
+ sym1 = sym2 = isSpecial1 = isSpecial2 = 0;
+
+ if (cond & PCC_REGISTER) {
+ sym1 = symFromStr (pic16_get_op (pci->pcop, NULL, 0));
+ reg1 = pic16_getRegFromInstruction (pc);
+ isSpecial1 = pic16_symIsSpecial (sym1);
+ }
+ if (cond & PCC_REGISTER2) {
+ sym2 = symFromStr (pic16_get_op2 (pci->pcop, NULL, 0));
+ reg2 = pic16_getRegFromInstruction (pc);
+ isSpecial2 = pic16_symIsSpecial (sym2);
+ }
+
+ /* determine input values */
+ val = list;
+ while (val && val->pc != pc) val = val->next;
+ //list = val; /* might save some time later... */
+ while (val && val->pc == pc) {
+ val->in_val = 0;
+ if (val->sym != 0 && (1 || val->acc.access.isRead)) {
+ /* get valnum for sym */
+ count = defmapFindAll (val->sym, pc, &oldval);
+ //fprintf (stderr, "%d defs for sym %s\n", count, strFromSym (val->sym));
+ if (count == 1) {
+ if ((val->acc.access.in_mask & oldval->acc.access.mask) == val->acc.access.in_mask) {
+ val->in_val = oldval->val;
+ } else {
+ val->in_val = 0;
+ }
+ } else if (count == 0) {
+ /* no definition found */
+ val->in_val = 0;
+ } else {
+ /* multiple definition(s) found -- value not known (unless always the same valnum) */
+ assert (oldval);
+ dummy = oldval->next;
+ mask = oldval->acc.access.mask;
+ val->in_val = oldval->val;
+ while (dummy && (dummy->val == val->in_val)) {
+ mask &= dummy->acc.access.mask;
+ dummy = dummy->next;
+ } // while
+
+ /* found other values or to restictive mask */
+ if (dummy || ((mask & val->acc.access.in_mask) != val->acc.access.in_mask)) {
+ val->in_val = 0;
+ }
+ }
+ if (count > 0) deleteDefmapChain (&oldval);
+ } // if
+ val = val->next;
+ }
+
+ /* handle valnum assignment */
+ switch (pci->op) {
+ case POC_CLRF: /* modifies STATUS (Z) */
+ if (!isSpecial1 && pic16_regIsLocal (reg1)) {
+ oldval = defmapCurr (list, sym1, pc);
+ if (oldval && (litFromValnum (oldval->in_val) == 0)) {
+ //fprintf (stderr, "%s: REG (%s) already set up correctly (%x)\n", pci->mnemonic, strFromSym(sym1), oldval->in_val);
+ if (!pic16_isAlive (SPO_STATUS, pc)) pic16_safepCodeRemove (pc, "=DF= redundant CLRF removed");
+ }
+ defmapUpdate (list, sym1, pc, valnumFromLit(0));
+ }
+ break;
+
+ case POC_SETF: /* SETF does not touch STATUS */
+ if (!isSpecial1 && pic16_regIsLocal (reg1)) {
+ oldval = defmapCurr (list, sym1, pc);
+ if (oldval && (litFromValnum (oldval->in_val) == 0x00FF)) {
+ //fprintf (stderr, "%s: REG (%s) already set up correctly (%x)\n", pci->mnemonic, strFromSym(sym1), oldval->in_val);
+ pic16_safepCodeRemove (pc, "=DF= redundant SETF removed");
+ }
+ defmapUpdate (list, sym1, pc, valnumFromLit (0x00FF));
+ }
+ break;
+
+ case POC_MOVLW: /* does not touch STATUS */
+ oldval = defmapCurr (list, SPO_WREG, pc);
+ if (pci->pcop->type == PO_LITERAL) {
+ //fprintf (stderr, "MOVLW: literal %u\n", PCOL(pci->pcop)->lit);
+ litnum = valnumFromLit ((unsigned char)PCOL(pci->pcop)->lit);
+ } else {
+ //fprintf (stderr, "MOVLW: %s\n", pic16_get_op (pci->pcop, NULL, 0));
+ litnum = valnumFromStr (pic16_get_op (pci->pcop, NULL, 0));
+ }
+ if (oldval && oldval->in_val == litnum) {
+ //fprintf (stderr, "%s: W already set up correctly (%x)\n", PCI(pc)->mnemonic, oldval->in_val);
+ pic16_safepCodeRemove (pc, "=DF= redundant MOVLW removed");
+ }
+ defmapUpdate (list, SPO_WREG, pc, litnum);
+ break;
+
+ case POC_ANDLW: /* modifies STATUS (Z,N) */
+ case POC_IORLW: /* modifies STATUS (Z,N) */
+ case POC_XORLW: /* modifies STATUS (Z,N) */
+ /* can be optimized iff WREG contains a known literal (0x100 - 0x1FF) */
+ if (pci->pcop->type == PO_LITERAL) {
+ int vallit = -1;
+ lit = (unsigned char) PCOL(pci->pcop)->lit;
+ val = defmapCurr (list, SPO_WREG, pc);
+ if (val) vallit = litFromValnum (val->in_val);
+ if (vallit != -1) {
+ /* xxxLW <literal>, WREG contains a known literal */
+ //fprintf (stderr, "%s 0x%02x, WREG: 0x%x\n", pci->mnemonic, lit, vallit);
+ if (pci->op == POC_ANDLW) {
+ lit &= vallit;
+ } else if (pci->op == POC_IORLW) {
+ lit |= vallit;
+ } else if (pci->op == POC_XORLW) {
+ lit ^= vallit;
+ } else {
+ assert (0 && "invalid operation");
+ }
+ if (vallit == lit) {
+ //fprintf (stderr, "%s: W already set up correctly (%x = val %x)\n", pci->mnemonic, vallit, val->in_val);
+ if (!pic16_isAlive (SPO_STATUS, pc)) pic16_safepCodeRemove (pc, "=DF= redundant ANDLW/IORLW/XORLW removed");
+ }
+ defmapUpdate (list, SPO_WREG, pc, valnumFromLit (lit));
+ } // if
+ }
+ break;
+
+ case POC_LFSR:
+ {
+ /* check if old value matches new value */
+ int lit;
+ int ok = 1;
+ assert (pci->pcop->type == PO_LITERAL);
+
+ lit = PCOL(pci->pcop)->lit;
+
+ val = defmapCurr (list, pic16_fsrsym_idx[lit][0], pc);
+
+ if (val && (val->in_val != 0) && (val->in_val == val->val)) {
+ //fprintf (stderr, "FSR%dL already set up correctly at %p (%x)\n", lit, pc, val->val);
+ } else {
+ /* cannot remove this LFSR */
+ ok = 0;
+ } // if
+
+ val = defmapCurr (list, pic16_fsrsym_idx[lit][1], pc);
+ if (val && (val->in_val != 0) && (val->in_val == val->val)) {
+ //fprintf (stderr, "FSR%dH already set up correctly at %p (%x)\n", lit, pc, val->val);
+ } else {
+ ok = 0;
+ } // if
+
+ if (ok) {
+ pic16_safepCodeRemove (pc, "=DF= redundant LFSR removed");
+ }
+ }
+ break;
+
+ case POC_MOVWF: /* does not touch flags */
+ /* find value of WREG */
+ val = defmapCurr (list, SPO_WREG, pc);
+ oldval = defmapCurr (list, sym1, pc);
+ if (val) lit = litFromValnum (val->in_val);
+ else lit = -1;
+ //fprintf (stderr, "MOVWF: lit: %i (%x, %x)\n", lit, lit, val->in_val);
+
+ if ((lit == 0 || lit == 0x0ff) && !pic16_isAlive (SPO_STATUS, pc)) {
+ /* might replace with CLRF/SETF (will possibly make previous MOVLW 0x00/0xff unneccessary --> dead code elimination) */
+ //fprintf (stderr, "replacing MOVWF with CLRF/SETF\n");
+ if (lit == 0) {
+ newpc = pic16_newpCode (POC_CLRF, pic16_pCodeOpCopy (pci->pcop));
+ } else {
+ assert (lit == 0x0ff);
+ newpc = pic16_newpCode (POC_SETF, pic16_pCodeOpCopy (pci->pcop));
+ }
+ if (pic16_debug_verbose || pic16_pcode_verbose) pic16_InsertCommentAfter (pc->prev, "=DF= MOVWF: replaced by CLRF/SETF");
+ pic16_pCodeReplace (pc, newpc);
+ defmapReplaceSymRef (pc, SPO_WREG, 0, 1);
+ pic16_fixDefmap (pc, newpc);
+ pc = newpc;
+
+ /* This breaks the defmap chain's references to pCodes... fix it! */
+ if (!val->prev) PCI(pc)->pcflow->defmap = val->next;
+ if (!val->acc.access.isWrite) {
+ deleteDefmap (val); // delete reference to WREG as in value
+ val = NULL;
+ } else {
+ val->acc.access.isRead = 0; // delete reference to WREG as in value
+ }
+ oldval = PCI(pc)->pcflow->defmap;
+ while (oldval) {
+ if (oldval->pc == pc) oldval->pc = newpc;
+ oldval = oldval->next;
+ } // while
+ } else if (!isSpecial1 && pic16_regIsLocal (reg1) && val && oldval && (val->in_val != 0) && (val->in_val == oldval->in_val)) {
+ //fprintf (stderr, "MOVWF: F (%s) already set up correctly (%x) at %p\n", strFromSym (sym1), oldval->in_val, pc);
+ pic16_safepCodeRemove (pc, "=DF= redundant MOVWF removed");
+ }
+ if (val) defmapUpdate (list, sym1, pc, val->in_val);
+ break;
+
+ case POC_MOVFW: /* modifies STATUS (Z,N) */
+ /* find value of REG */
+ if (!isSpecial1 && pic16_regIsLocal (reg1)) {
+ val = defmapCurr (list, sym1, pc);
+ oldval = defmapCurr (list, SPO_WREG, pc);
+ if (val && oldval && (val->in_val != 0) && (val->in_val == oldval->in_val)) {
+ //fprintf (stderr, "MOVFW: W already set up correctly (%x) at %p\n", oldval->in_val, pc);
+ if (!pic16_isAlive (SPO_STATUS, pc)) pic16_safepCodeRemove (pc, "=DF= redundant MOVFW removed");
+ }
+ if (val) defmapUpdate (list, SPO_WREG, pc, val->in_val);
+ }
+ break;
+
+ case POC_MOVFF: /* does not touch STATUS */
+ /* find value of REG */
+ val = defmapCurr (list, sym1, pc);
+ oldval = defmapCurr (list, sym2, pc);
+ if (val) lit = litFromValnum (val->in_val);
+ else lit = -1;
+ newpc = NULL;
+ if (!isSpecial1 && pic16_regIsLocal (reg1) && val && oldval && !pic16_isAlive (SPO_STATUS, pc)) {
+ //pc->print (stderr, pc); fprintf (stderr, "lit: %d (%x, %x)\n", lit, lit, val->in_val);
+ if (lit == 0) {
+ newpc = pic16_newpCode (POC_CLRF, PCOP2(pci->pcop)->pcopR);
+ } else if (lit == 0x00ff) {
+ newpc = pic16_newpCode (POC_SETF, PCOP2(pci->pcop)->pcopR);
+ } else {
+ newpc = NULL;
+ }
+ if (newpc) {
+ pic16_InsertCommentAfter (pc->prev, "=DF= MOVFF: replaced by CRLF/SETF");
+ pic16_df_saved_bytes += PCI(pc)->isize - PCI(newpc)->isize;
+ pic16_pCodeReplace (pc, newpc);
+ defmapReplaceSymRef (pc, sym1, 0, 1);
+ pic16_fixDefmap (pc, newpc);
+ pc = newpc;
+ break; // do not process instruction as MOVFF...
+ }
+ } else if (!isSpecial1 && !isSpecial2
+ && pic16_regIsLocal (reg1) && pic16_regIsLocal (reg2)
+ && val && oldval && (val->in_val != 0)) {
+ if (val->in_val == oldval->in_val) {
+ //fprintf (stderr, "MOVFF: F2 (%s) already set up correctly (%x) at %p\n", strFromSym (sym2), oldval->in_val, pc);
+ pic16_safepCodeRemove (pc, "=DF= redundant MOVFF removed");
+ } else {
+ if (!pic16_isAlive (sym1, pc)) {
+ defmap_t *copy = NULL;
+ /* If there is another symbol S storing sym1's value we should assign from S thus shortening the liferange of sym1.
+ * This should help eliminate
+ * MOVFF A,B
+ * <do something not changing A or using B>
+ * MOVFF B,C
+ * <B is not alive anymore>
+ * and turn it into
+ * <do something not changing A or using B>
+ * MOVFF A,C
+ */
+
+ /* scan defmap for symbols storing sym1's value */
+ while (oldval && (oldval->pc == pc || oldval->in_val != val->in_val)) oldval = oldval->next;
+ if (oldval && (oldval->sym != sym1) && defmapFindAll (oldval->sym, pc, ©) == 1) {
+ /* unique reaching definition for sym found */
+ if (copy->val && copy->val == val->in_val) {
+ //fprintf (stderr, "found replacement symbol for %s (val %x) <-- %s (assigned %x @ %p)\n", strFromSym(sym1), val->in_val, strFromSym(copy->sym), copy->val, copy->pc);
+ if (copy->sym == SPO_WREG) {
+ newpc = pic16_newpCode (POC_MOVWF, pic16_pCodeOpCopy (PCOP2(pci->pcop)->pcopR));
+ } else {
+ pCodeOp *pcop = NULL;
+ /* the code below fails if we try to replace
+ * MOVFF PRODL, r0x03
+ * MOVFF r0x03, PCLATU
+ * with
+ * MOVFF PRODL, PCLATU
+ * as copy(PRODL) contains has pc==NULL, by name fails...
+ */
+ if (!copy->pc || !PCI(copy->pc)->pcop) break;
+
+ if (copy->pc && PCI(copy->pc)->pcop)
+ pcop = PCI(copy->pc)->pcop;
+#if 0
+ /* This code is broken--see above. */
+ else
+ {
+ const char *symname = strFromSym(copy->sym);
+
+ assert( symname );
+ pic16_InsertCommentAfter (pc->prev, "BUG-ME");
+ pic16_InsertCommentAfter (pc->prev, "=DF= MOVFF: newpCodeOpregFromStr(%s)", (char *)symname);
+ //pcop = pic16_newpCodeOpRegFromStr((char *)symname);
+ }
+#endif
+ assert( pcop );
+ newpc = pic16_newpCode(POC_MOVFF, pic16_popGet2p(
+ pcop,
+ pic16_pCodeOpCopy (PCOP2(pci->pcop)->pcopR)));
+ }
+ pic16_InsertCommentAfter (pc->prev, "=DF= MOVFF: SRC op %s replaced by %s", strFromSym(sym1), strFromSym(copy->sym));
+ pic16_df_saved_bytes += PCI(pc)->isize - PCI(newpc)->isize;
+ pic16_pCodeReplace (pc, newpc);
+ assert (val->sym == sym1 && val->acc.access.isRead && !val->acc.access.isWrite);
+ defmapReplaceSymRef (pc, sym1, copy->sym, 1);
+ pic16_fixDefmap (pc, newpc);
+ pc = newpc;
+ }
+ }
+ deleteDefmapChain (©);
+ }
+ }
+ if (val) defmapUpdate (list, sym2, pc, val->in_val);
+ }
+ break;
+
+ default:
+ /* cannot optimize */
+ break;
+ } // switch
+}
+
+static void pic16_destructDF (pBlock *pb) {
+ pCode *pc, *next;
+
+ /* remove old defmaps */
+ pc = pic16_findNextInstruction (pb->pcHead);
+ while (pc) {
+ next = pic16_findNextInstruction (pc->next);
+
+ assert (isPCI(pc) || isPCAD(pc));
+ assert (PCI(pc)->pcflow);
+ deleteDefmapChain (&PCI(pc)->pcflow->defmap);
+ deleteDefmapChain (&PCI(pc)->pcflow->in_vals);
+ deleteDefmapChain (&PCI(pc)->pcflow->out_vals);
+
+ pc = next;
+ } // while
+
+ if (defmap_free || defmap_free_count) {
+ //fprintf (stderr, "released defmaps: %u -- freeing up memory\n", defmap_free_count);
+ freeDefmap (&defmap_free);
+ defmap_free_count = 0;
+ }
+}
+
+/* Checks whether a pBlock contains ASMDIRs. */
+static int pic16_pBlockHasAsmdirs (pBlock *pb) {
+ pCode *pc;
+
+ pc = pic16_findNextInstruction (pb->pcHead);
+ while (pc) {
+ if (isPCAD(pc)) return 1;
+
+ pc = pic16_findNextInstruction (pc->next);
+ } // while
+
+ /* no PCADs found */
+ return 0;
+}
+
+#if 1
+/* Remove MOVFF r0x??, POSTDEC1 and MOVFF PREINC1, r0x?? for otherwise unused registers. */
+static int pic16_removeUnusedRegistersDF () {
+ pCode *pc, *pc2;
+ pBlock *pb;
+ regs *reg1, *reg2, *reg3;
+ set *seenRegs = NULL;
+ int cond, i;
+ int islocal, change = 0;
+
+ /* no pBlocks? */
+ if (!the_pFile || !the_pFile->pbHead) return 0;
+
+ for (pb = the_pFile->pbHead; pb; pb = pb->next) {
+ //fprintf (stderr, "%s: examining function %s\n", __FUNCTION__, pic16_pBlockGetFunctionName (pb));
+#if 1
+ /* find set of using pCodes per register */
+ for (pc = pic16_findNextInstruction (pb->pcHead); pc;
+ pc = pic16_findNextInstruction(pc->next)) {
+
+ cond = PCI(pc)->inCond | PCI(pc)->outCond;
+ reg1 = reg2 = NULL;
+ if (cond & PCC_REGISTER) reg1 = pic16_getRegFromInstruction (pc);
+ if (cond & PCC_REGISTER2) reg2 = pic16_getRegFromInstruction2 (pc);
+
+ if (reg1) {
+ if (!isinSet (seenRegs, reg1)) reg1->reglives.usedpCodes = NULL;
+ addSetIfnotP (&seenRegs, reg1);
+ addSetIfnotP (®1->reglives.usedpCodes, pc);
+ }
+ if (reg2) {
+ if (!isinSet (seenRegs, reg2)) reg2->reglives.usedpCodes = NULL;
+ addSetIfnotP (&seenRegs, reg2);
+ addSetIfnotP (®2->reglives.usedpCodes, pc);
+ }
+ } // for pc
+#endif
+ for (reg1 = setFirstItem (seenRegs); reg1; reg1 = setNextItem (seenRegs)) {
+ /* may not use pic16_regIsLocal() here -- in interrupt routines
+ * WREG, PRODx, FSR0x must be saved */
+ islocal = (reg1->isLocal || reg1->rIdx == pic16_framepnt_lo->rIdx || reg1->rIdx == pic16_framepnt_hi->rIdx);
+ if (islocal && elementsInSet (reg1->reglives.usedpCodes) == 2) {
+ pc = pc2 = NULL;
+ for (i=0; i < 2; i++) {
+ pc = (pCode *) indexSet(reg1->reglives.usedpCodes, i);
+ if (!pc2) pc2 = pc;
+ if (!isPCI(pc) || !PCI(pc)->op == POC_MOVFF) continue;
+ reg2 = pic16_getRegFromInstruction (pc);
+ reg3 = pic16_getRegFromInstruction2 (pc);
+ if (!reg2 || !reg3
+ || (reg2->rIdx != pic16_stack_preinc->rIdx
+ && reg3->rIdx != pic16_stack_postdec->rIdx)) break;
+ if (i == 1) {
+ /* both pCodes are MOVFF R,POSTDEC1 / MOVFF PREINC1,R */
+ //fprintf (stderr, "%s: removing local register %s from %s\n", __FUNCTION__, reg1->name, pic16_pBlockGetFunctionName (pb));
+ pic16_safepCodeRemove (pc, "removed unused local reg IN");
+ pic16_safepCodeRemove (pc2, "removed unused local reg OUT");
+ }
+ } // for
+ } // if
+ deleteSet (®1->reglives.usedpCodes);
+ } // for reg1
+
+ deleteSet (&seenRegs);
+ } // for pb
+
+ return change;
+}
+#endif
+
+/* Set up pCodeFlow's defmap_ts.
+ * Needs correctly set up to/from fields. */
+static void pic16_createDF (pBlock *pb) {
+ pCode *pc, *next;
+ int change=0;
+
+ //fprintf (stderr, "creating DF for pb %p (%s)\n", pb, pic16_pBlockGetFunctionName (pb));
+
+ pic16_destructDF (pb);
+
+ /* check pBlock: do not analyze pBlocks with ASMDIRs (for now...) */
+ if (pic16_pBlockHasAsmdirs (pb)) {
+ //fprintf (stderr, "%s: pBlock contains ASMDIRs -- data flow analysis not performed!\n", __FUNCTION__);
+ return;
+ }
+
+ /* integrity check -- we need to reach all flows to guarantee
+ * correct data flow analysis (reaching definitions, aliveness) */
+#if 0
+ if (!verifyAllFlowsReachable (pb)) {
+ fprintf (stderr, "not all flows reachable -- aborting dataflow analysis for %s!\n", pic16_pBlockGetFunctionName (pb));
+ return;
+ }
+#endif
+
+ /* establish new defmaps */
+ pc = pic16_findNextInstruction (pb->pcHead);
+ while (pc) {
+ next = pic16_findNextInstruction (pc->next);
+
+ assert (PCI(pc)->pcflow);
+ PCI(pc)->pcflow->defmap = createDefmap (pc, PCI(pc)->pcflow->defmap);
+
+ pc = next;
+ } // while
+
+ //fprintf (stderr, "%s: creating reaching definitions...\n", __FUNCTION__);
+ createReachingDefinitions (pb);
+
+#if 1
+ /* assign better valnums */
+ //fprintf (stderr, "assigning valnums for pb %p\n", pb);
+ pc = pic16_findNextInstruction (pb->pcHead);
+ while (pc) {
+ next = pic16_findNextInstruction (pc->next);
+
+ assert (PCI(pc)->pcflow);
+ assignValnums (pc);
+
+ pc = next;
+ } // while
+#endif
+
+#if 1
+ /* remove dead pCodes */
+ //fprintf (stderr, "removing dead pCodes in %p (%s)\n", pb, pic16_pBlockGetFunctionName (pb));
+ do {
+ change = 0;
+ pc = pic16_findNextInstruction (pb->pcHead);
+ while (pc) {
+ next = pic16_findNextInstruction (pc->next);
+
+ if (isPCI(pc) && !isPCI_BRANCH(pc) && !pic16_pCodeIsAlive (pc)) {
+ change += pic16_safepCodeRemove (pc, "=DF= removed dead pCode");
+ }
+
+ pc = next;
+ } // while
+ } while (change);
+#endif
+}
+
+/* ======================================================================== */
+/* === VCG DUMPER ROUTINES ================================================ */
+/* ======================================================================== */
+#if defined (DUMP_DF_GRAPHS) && DUMP_DF_GRAPHS > 0
+hTab *dumpedNodes = NULL;
+
+/** Dump VCG header into of. */
+static void pic16_vcg_init (FILE *of) {
+ /* graph defaults */
+ fprintf (of, "graph:{\n");
+ fprintf (of, "title:\"graph1\"\n");
+ fprintf (of, "label:\"graph1\"\n");
+ fprintf (of, "color:white\n");
+ fprintf (of, "textcolor:black\n");
+ fprintf (of, "bordercolor:black\n");
+ fprintf (of, "borderwidth:1\n");
+ fprintf (of, "textmode:center\n");
+
+ fprintf (of, "layoutalgorithm:dfs\n");
+ fprintf (of, "late_edge_labels:yes\n");
+ fprintf (of, "display_edge_labels:yes\n");
+ fprintf (of, "dirty_edge_labels:yes\n");
+ fprintf (of, "finetuning:yes\n");
+ fprintf (of, "ignoresingles:no\n");
+ fprintf (of, "straight_phase:yes\n");
+ fprintf (of, "priority_phase:yes\n");
+ fprintf (of, "manhattan_edges:yes\n");
+ fprintf (of, "smanhattan_edges:no\n");
+ fprintf (of, "nearedges:no\n");
+ fprintf (of, "node_alignment:center\n"); // bottom|top|center
+ fprintf (of, "port_sharing:no\n");
+ fprintf (of, "arrowmode:free\n"); // fixed|free
+ fprintf (of, "crossingphase2:yes\n");
+ fprintf (of, "crossingoptimization:yes\n");
+ fprintf (of, "edges:yes\n");
+ fprintf (of, "nodes:yes\n");
+ fprintf (of, "splines:no\n");
+
+ /* node defaults */
+ fprintf (of, "node.color:lightyellow\n");
+ fprintf (of, "node.textcolor:black\n");
+ fprintf (of, "node.textmode:center\n");
+ fprintf (of, "node.shape:box\n");
+ fprintf (of, "node.bordercolor:black\n");
+ fprintf (of, "node.borderwidth:1\n");
+
+ /* edge defaults */
+ fprintf (of, "edge.textcolor:black\n");
+ fprintf (of, "edge.color:black\n");
+ fprintf (of, "edge.thickness:1\n");
+ fprintf (of, "edge.arrowcolor:black\n");
+ fprintf (of, "edge.backarrowcolor:black\n");
+ fprintf (of, "edge.arrowsize:15\n");
+ fprintf (of, "edge.backarrowsize:15\n");
+ fprintf (of, "edge.arrowstyle:line\n"); // none|solid|line
+ fprintf (of, "edge.backarrowstyle:none\n"); // none|solid|line
+ fprintf (of, "edge.linestyle:continuous\n"); // continuous|solid|dotted|dashed|invisible
+
+ fprintf (of, "\n");
+
+ /* prepare data structures */
+ if (dumpedNodes) {
+ hTabDeleteAll (dumpedNodes);
+ dumpedNodes = NULL;
+ }
+ dumpedNodes = newHashTable (128);
+}
+
+/** Dump VCG footer into of. */
+static void pic16_vcg_close (FILE *of) {
+ fprintf (of, "}\n");
+}
+
+#define BUF_SIZE 128
+#define pcTitle(pc) (SNPRINTF (buf, BUF_SIZE, "n_%p, %p/%u", PCODE(pc), isPCI(pc) ? PCI(pc)->pcflow : NULL, PCODE(pc)->seq), &buf[0])
+
+#if 0
+static int ptrcmp (const void *p1, const void *p2) {
+ return p1 == p2;
+}
+#endif
+
+/** Dump a pCode node as VCG to of. */
+static void pic16_vcg_dumpnode (pCode *pc, FILE *of) {
+ char buf[BUF_SIZE];
+
+ if (hTabFindByKey (dumpedNodes, (((char *) pc - (char *) 0)>>2) % 128, pc, ptrcmp)) {
+ // dumped already
+ return;
+ }
+ hTabAddItemLong (&dumpedNodes, (((char *) pc - (char *) 0)>>2) % 128, pc, pc);
+ //fprintf (stderr, "dumping %p\n", pc);
+
+ /* only dump pCodeInstructions and Flow nodes */
+ if (!isPCI(pc) && !isPCAD(pc) && !isPCFL(pc)) return;
+
+ /* emit node */
+ fprintf (of, "node:{");
+ fprintf (of, "title:\"%s\" ", pcTitle(pc));
+ fprintf (of, "label:\"%s\n", pcTitle(pc));
+ if (isPCFL(pc)) {
+ fprintf (of, "<PCFLOW>");
+ } else if (isPCI(pc) || isPCAD(pc)) {
+ pc->print (of, pc);
+ } else {
+ fprintf (of, "<!PCI>");
+ }
+ fprintf (of, "\" ");
+ fprintf (of, "}\n");
+
+ if (1 && isPCFL(pc)) {
+ defmap_t *map, *prev;
+ unsigned int i;
+ map = PCFL(pc)->defmap;
+ i=0;
+ while (map) {
+ if (map->sym != 0) {
+ i++;
+
+ /* emit definition node */
+ fprintf (of, "node:{title:\"%s_def%u\" ", pcTitle(pc), i);
+ fprintf (of, "label:\"");
+
+ prev = map;
+ do {
+ fprintf (of, "%s%c%c: val %4x|%4x & %02x|%02x, sym %s", (prev == map) ? "" : "\n", map->acc.access.isRead ? 'R' : ' ', map->acc.access.isWrite ? 'W' : ' ', map->in_val, map->val, map->acc.access.in_mask, map->acc.access.mask, strFromSym (map->sym));
+ prev = map;
+ map = map->next;
+ } while (map && prev->pc == map->pc);
+ map = prev;
+
+ fprintf (of, "\" ");
+
+ fprintf (of, "color:green ");
+ fprintf (of, "}\n");
+
+ /* emit edge to previous definition */
+ fprintf (of, "edge:{sourcename:\"%s_def%u\" ", pcTitle(pc), i);
+ if (i == 1) {
+ fprintf (of, "targetname:\"%s\" ", pcTitle(pc));
+ } else {
+ fprintf (of, "targetname:\"%s_def%u\" ", pcTitle(pc), i-1);
+ }
+ fprintf (of, "color:green ");
+ fprintf (of, "}\n");
+
+ if (map->pc) {
+ pic16_vcg_dumpnode (map->pc, of);
+ fprintf (of, "edge:{sourcename:\"%s_def%u\" ", pcTitle(pc), i);
+ fprintf (of, "targetname:\"%s\" linestyle:dashed color:lightgreen}\n", pcTitle(map->pc));
+ }
+ }
+ map = map->next;
+ } // while
+ }
+
+ /* emit additional nodes (e.g. operands) */
+}
+
+/** Dump a pCode's edges (control flow/data flow) as VCG to of. */
+static void pic16_vcg_dumpedges (pCode *pc, FILE *of) {
+ char buf[BUF_SIZE];
+ pCodeInstruction *pci;
+ pBranch *curr;
+ int i;
+
+ if (1 && isPCFL(pc)) {
+ /* emit edges to flow successors */
+ void *pcfl;
+ //fprintf (stderr, "PCFLOWe @ %p\n", pc);
+ pcfl = setFirstItem (PCFL(pc)->to);
+ while (pcfl) {
+ pcfl = ((pCodeFlowLink *) (pcfl))->pcflow;
+ pic16_vcg_dumpnode (pc, of);
+ pic16_vcg_dumpnode ((pCode *) pcfl, of);
+ fprintf (of, "edge:{sourcename:\"%s\" ", pcTitle(pc));
+ fprintf (of, "targetname:\"%s\" color:lightred linestyle:dashed}\n", pcTitle(pcfl));
+ pcfl = setNextItem (PCFL(pc)->to);
+ } // while
+ } // if
+
+ if (!isPCI(pc) && !isPCAD(pc)) return;
+
+ pci = PCI(pc);
+
+ /* emit control flow edges (forward only) */
+ curr = pci->to;
+ i=0;
+ while (curr) {
+ pic16_vcg_dumpnode (curr->pc, of);
+ fprintf (of, "edge:{");
+ fprintf (of, "sourcename:\"%s\" ", pcTitle(pc));
+ fprintf (of, "targetname:\"%s\" ", pcTitle(curr->pc));
+ fprintf (of, "color:red ");
+ fprintf (of, "}\n");
+ curr = curr->next;
+ } // while
+
+#if 1
+ /* dump "flow" edge (link pCode according to pBlock order) */
+ {
+ pCode *pcnext;
+ pcnext = pic16_findNextInstruction (pc->next);
+ if (pcnext) {
+ pic16_vcg_dumpnode (pcnext, of);
+ fprintf (of, "edge:{sourcename:\"%s\" ", pcTitle(pc));
+ fprintf (of, "targetname:\"%s\" color:red linestyle:solid}\n", pcTitle(pcnext));
+ }
+ }
+#endif
+
+#if 0
+ /* emit flow */
+ if (pci->pcflow) {
+ pic16_vcg_dumpnode (&pci->pcflow->pc, of);
+ fprintf (of, "edge:{sourcename:\"%s\" ", pcTitle(pc));
+ fprintf (of, "targetname:\"%s\" color:lightblue linestyle:dashed}\n", pcTitle (pci->pcflow));
+ }
+#endif
+
+ /* emit data flow edges (backward only) */
+ /* TODO: gather data flow information... */
+}
+
+static void pic16_vcg_dump (FILE *of, pBlock *pb) {
+ pCode *pc;
+
+ /* check pBlock: do not analyze pBlocks with ASMDIRs (for now...) */
+ if (pic16_pBlockHasAsmdirs (pb)) {
+ //fprintf (stderr, "%s: pBlock contains ASMDIRs -- data flow analysis not performed!\n", __FUNCTION__);
+ return;
+ }
+
+ for (pc=pb->pcHead; pc; pc = pc->next) {
+ pic16_vcg_dumpnode (pc, of);
+ } // for pc
+
+ for (pc=pb->pcHead; pc; pc = pc->next) {
+ pic16_vcg_dumpedges (pc, of);
+ } // for pc
+}
+
+static void pic16_vcg_dump_default (pBlock *pb) {
+ FILE *of;
+ char buf[BUF_SIZE];
+ pCode *pc;
+
+ /* get function name */
+ pc = pb->pcHead;
+ while (pc && !isPCF(pc)) pc = pc->next;
+ if (pc) {
+ SNPRINTF (buf, BUF_SIZE, "%s_%s.vcg", PCF(pc)->modname, PCF(pc)->fname);
+ } else {
+ SNPRINTF (buf, BUF_SIZE, "pb_%p.vcg", pb);
+ }
+
+ //fprintf (stderr, "now dumping %s\n", buf);
+ of = fopen (buf, "w");
+ pic16_vcg_init (of);
+ pic16_vcg_dump (of, pb);
+ pic16_vcg_close (of);
+ fclose (of);
+}
+#endif
+
+/*** END of helpers for pCode dataflow optimizations ***/