+/*------------------------------------------------------------------------
+
+ SDCCralloc.c - source file for register allocation. (xa51) specific
+
+ Written By - Sandeep Dutta . sandeep.dutta@usa.net (1998)
+
+ This program is free software; you can redistribute it and/or modify it
+ under the terms of the GNU General Public License as published by the
+ Free Software Foundation; either version 2, or (at your option) any
+ later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+ In other words, you are welcome to use, share and improve this program.
+ You are forbidden to forbid anyone else to use, share and improve
+ what you give them. Help stamp out software-hoarding!
+-------------------------------------------------------------------------*/
+
+#include "common.h"
+#include "ralloc.h"
+#include "gen.h"
+
+/*-----------------------------------------------------------------*/
+/* At this point we start getting processor specific although */
+/* some routines are non-processor specific & can be reused when */
+/* targetting other processors. The decision for this will have */
+/* to be made on a routine by routine basis */
+/* routines used to pack registers are most definitely not reusable */
+/* since the pack the registers depending strictly on the MCU */
+/*-----------------------------------------------------------------*/
+
+extern void genXA51Code (iCode *);
+#define D(x)
+
+/* Global data */
+static struct
+ {
+ bitVect *spiltSet;
+ set *stackSpil;
+ bitVect *regAssigned;
+ bitVect *totRegAssigned; /* final set of LRs that got into registers */
+ short blockSpil;
+ int slocNum;
+ bitVect *funcrUsed; /* registers used in a function */
+ int stackExtend;
+ int dataExtend;
+ }
+_G;
+
+/* xa51 registers */
+regs regsXA51[]={
+ // index size type name regMask offset isFree symbol
+ {0x20, 2, REG_SCR, "r0", 0x0003, 0, 1, NULL}, // r0 used for scratch
+ {0x21, 2, REG_SCR, "r1", 0x000c, 2, 1, NULL}, // r1 used for scratch
+ {0x22, 2, REG_PTR, "r2", 0x0030, 4, 1, NULL},
+ {0x23, 2, REG_PTR, "r3", 0x00c0, 6, 1, NULL},
+ {0x24, 2, REG_PTR, "r4", 0x0300, 8, 1, NULL},
+ {0x25, 2, REG_PTR, "r5", 0x0c00, 10, 1, NULL},
+ {0x26, 2, REG_PTR, "r6", 0x3000, 12, 1, NULL},
+ {0x27, 2, REG_STK, "r7", 0xc000, 14, 1, NULL}, // r7=SP
+#if 0 // some derivates have even more! (only word access and gpr use)
+ {0x28, 2, REG_GPR, "r8", 0x10000, 16, 1, NULL},
+ {0x29, 2, REG_GPR, "r9", 0x20000, 18, 1, NULL},
+ {0x2a, 2, REG_GPR, "r10", 0x40000, 20, 1, NULL},
+ {0x2b, 2, REG_GPR, "r11", 0x80000, 22, 1, NULL},
+ {0x2c, 2, REG_GPR, "r12", 0x100000, 24, 1, NULL},
+ {0x2d, 2, REG_GPR, "r13", 0x200000, 26, 1, NULL},
+ {0x2e, 2, REG_GPR, "r14", 0x400000, 28, 1, NULL},
+ {0x2f, 2, REG_GPR, "r15", 0x800000, 20, 1, NULL},
+#endif
+ {0x10, 1, REG_SCR, "r0h", 0x0001, 1, 1, NULL}, // r0h used for scratch
+ {0x11, 1, REG_SCR, "r0l", 0x0002, 1, 1, NULL}, // r0l used for scratch
+ {0x12, 1, REG_SCR, "r1h", 0x0004, 2, 1, NULL}, // r1h used for scratch
+ {0x13, 1, REG_SCR, "r1l", 0x0008, 3, 1, NULL}, // r1l used for scratch
+ {0x14, 1, REG_PTR, "r2h", 0x0010, 4, 1, NULL},
+ {0x15, 1, REG_PTR, "r2l", 0x0020, 5, 1, NULL},
+ {0x16, 1, REG_PTR, "r3h", 0x0040, 6, 1, NULL},
+ {0x17, 1, REG_PTR, "r3l", 0x0080, 7, 1, NULL},
+ {0x18, 1, REG_PTR, "r4h", 0x0100, 8, 1, NULL},
+ {0x19, 1, REG_PTR, "r4l", 0x0200, 9, 1, NULL},
+ {0x1a, 1, REG_PTR, "r5h", 0x0400, 10, 1, NULL},
+ {0x1b, 1, REG_PTR, "r5l", 0x0800, 11, 1, NULL},
+ {0x1c, 1, REG_PTR, "r6h", 0x1000, 12, 1, NULL},
+ {0x1d, 1, REG_PTR, "r6l", 0x2000, 13, 1, NULL},
+ {0x1e, 1, REG_STK, "r7h", 0x4000, 14, 1, NULL}, // r7=SP
+ {0x1f, 1, REG_STK, "r7l", 0x8000, 15, 1, NULL}, // r7=SP
+};
+
+int xa51_nRegs=sizeof(regsXA51)/sizeof(regs);
+
+udword xa51RegsInUse=0;
+
+// this should be set with a command line switch
+bool xa51HasGprRegs=0;
+
+/*-----------------------------------------------------------------*/
+/* xa51_regWithMask - returns pointer to register with mask */
+/*-----------------------------------------------------------------*/
+regs *xa51_regWithMask (udword mask) {
+ int i;
+ for (i=0; i<xa51_nRegs; i++) {
+ if (regsXA51[i].regMask==mask) {
+ return ®sXA51[i];
+ }
+ }
+ return NULL;
+}
+
+/*-----------------------------------------------------------------*/
+/* checkRegsMask - check the consistancy of the regMask redundancy */
+/*-----------------------------------------------------------------*/
+
+void checkRegMask(char *f) { // for debugging purposes only
+ int i;
+ udword regMask=0;
+
+ for (i=0; i<xa51_nRegs; i++) {
+ if (!regsXA51[i].isFree) {
+ regMask |= regsXA51[i].regMask;
+ }
+ }
+
+ if (regMask != xa51RegsInUse) {
+ fprintf (stderr, "error(%s): regMask inconsistent 0x%08x != 0x%08x\n",
+ f, regMask, xa51RegsInUse);
+ regMask=regMask^xa51RegsInUse;
+ fprintf (stderr, "%s used by %s\n",
+ xa51_regWithMask(regMask)->name,
+ xa51_regWithMask(regMask)->sym->name);
+
+ exit(1);
+ return;
+ }
+}
+
+char *regTypeToStr(short type) {
+ switch (type)
+ {
+ case REG_PTR: return "ptr"; break; // pointer
+ case REG_GPR: return "gpr"; break; // general purpose
+ case REG_CND: return "cnd"; break; // condition (bit)
+ case REG_STK: return "stk"; break; // stack
+ case REG_SCR: return "scr"; break; // scratch
+ default: return "???"; break;
+ }
+}
+
+/*-----------------------------------------------------------------*/
+/* freeReg - frees a previous allocated register */
+/*-----------------------------------------------------------------*/
+static void freeReg (regs * reg, bool silent) {
+
+ checkRegMask(__FUNCTION__);
+
+ if (!reg) {
+ werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
+ "freeReg - freeing NULL register");
+ return;
+ }
+
+ if (!silent) {
+ fprintf (stderr, "freeReg: (%08x) %s ", xa51RegsInUse, reg->name);
+ }
+
+ if (reg->isFree || ((xa51RegsInUse®->regMask)!=reg->regMask)) {
+ werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
+ "freeReg - freeing unused register(s)");
+ return;
+ }
+ xa51RegsInUse &= ~reg->regMask;
+ reg->isFree = 1;
+ reg->sym = NULL;
+ if (!silent) fprintf (stderr, "(%08x)\n", xa51RegsInUse);
+
+ checkRegMask(__FUNCTION__);
+}
+
+/*-----------------------------------------------------------------*/
+/* allocReg - allocates register of given size (byte, word) */
+/* and type (ptr, gpr, cnd) */
+/*-----------------------------------------------------------------*/
+static bool allocReg (short size, short type, symbol *sym,
+ short offset, bool silent) {
+ int i;
+
+ checkRegMask(__FUNCTION__);
+
+ if (!silent) {
+ fprintf (stderr, "allocReg (0x%08x) for %s size:%d, type:%s ",
+ xa51RegsInUse,
+ sym->name,
+ size, regTypeToStr(type));
+ }
+
+ switch (size)
+ {
+ // TODO: gaps should be filled for dwords too
+ case 1:
+ // let's see if we can fill a gap
+ for (i=0; i<xa51_nRegs; i++) {
+ if (regsXA51[i].size==2 && regsXA51[i].type==type) {
+ udword mask=regsXA51[i].regMask & ~xa51RegsInUse;
+ if (mask && mask!=regsXA51[i].regMask) {
+ regs *reg=xa51_regWithMask(mask);
+ // found a gap
+ sym->regs[offset]=reg;
+ xa51RegsInUse |= mask;
+ reg->isFree=0; // redundant
+ reg->sym = sym;
+ if (!silent) {
+ fprintf (stderr, "(using gap) %s\n", reg->name);
+ }
+ checkRegMask(__FUNCTION__);
+ return TRUE;
+ }
+ }
+ }
+ // no we can't, fall through
+ case 2:
+ for (i=0; i<xa51_nRegs; i++) {
+ if (regsXA51[i].size==size &&
+ regsXA51[i].type==type &&
+ (regsXA51[i].regMask & xa51RegsInUse)==0) {
+ xa51RegsInUse |= regsXA51[i].regMask;
+ regsXA51[i].isFree = 0; // redundant
+ regsXA51[i].sym = sym;
+ if (!silent) {
+ fprintf (stderr, "%s\n", regsXA51[i].name);
+ }
+ sym->regs[offset]=®sXA51[i];
+ checkRegMask(__FUNCTION__);
+ return TRUE;
+ }
+ }
+ if (!silent) {
+ fprintf (stderr, "failed (%08x)\n", xa51RegsInUse);
+ }
+ checkRegMask(__FUNCTION__);
+ return FALSE;
+ break;
+ case 3:
+ // this must be a generic pointer
+ if (!silent) {
+ fprintf (stderr, "trying 2+1\n");
+ }
+ // get the pointer part
+ if (allocReg (2, REG_PTR, sym, offset, silent)) {
+ // get the generic part
+ if ((xa51HasGprRegs && allocReg (1, REG_GPR, sym, offset+1, silent)) ||
+ allocReg (1, REG_PTR, sym, offset+1, silent)) {
+ checkRegMask(__FUNCTION__);
+ return TRUE;
+ }
+ freeReg(sym->regs[offset], silent);
+ sym->regs[offset]=NULL;
+ }
+ checkRegMask(__FUNCTION__);
+ return FALSE;
+ break;
+ case 4: // this is a dword
+ if (!silent) {
+ fprintf (stderr, "trying 2+2\n");
+ }
+ if ((xa51HasGprRegs && allocReg (2, REG_GPR, sym, offset, silent)) ||
+ allocReg (2, REG_PTR, sym, offset, silent)) {
+ if ((xa51HasGprRegs && allocReg (2, REG_GPR, sym, offset+1, silent)) ||
+ allocReg (2, REG_PTR, sym, offset+1, silent)) {
+ checkRegMask(__FUNCTION__);
+ return TRUE;
+ }
+ }
+ freeReg(sym->regs[offset], FALSE);
+ sym->regs[offset]=NULL;
+ checkRegMask(__FUNCTION__);
+ return FALSE;
+ break;
+ default:
+ fprintf (stderr, "\nallocReg: cannot allocate reg of size %d\n", size);
+ exit (1);
+ break;
+ }
+ // we should never come here
+ return FALSE;
+}
+
+/*-------------------------------------------------------------------*/
+/* freeAllRegs - frees all registers */
+/*-------------------------------------------------------------------*/
+// just to be sure, this should not be needed
+static void freeAllRegs (void) {
+ char regsFreed[132];
+ int i;
+ int nfr = 0;
+
+ checkRegMask(__FUNCTION__);
+
+ regsFreed[0]=0;
+ for (i=0; i<xa51_nRegs; i++) {
+ if (!regsXA51[i].isFree) {
+ strcat (regsFreed, regsXA51[i].name);
+ strcat (regsFreed, " ");
+ regsXA51[i].isFree=1;
+ regsXA51[i].sym=NULL;
+ nfr++;
+ }
+ }
+ xa51RegsInUse=0;
+ if (nfr) {
+ fprintf (stderr, "freeAllRegisters: %d regs freed (%s)\n", nfr, regsFreed);
+ exit (1);
+ }
+}
+
+/*-----------------------------------------------------------------*/
+/* allDefsOutOfRange - all definitions are out of a range */
+/*-----------------------------------------------------------------*/
+static bool allDefsOutOfRange (bitVect * defs, int fseq, int toseq) {
+ int i;
+
+ if (!defs)
+ return TRUE;
+
+ for (i = 0; i < defs->size; i++)
+ {
+ iCode *ic;
+
+ if (bitVectBitValue (defs, i) &&
+ (ic = hTabItemWithKey (iCodehTab, i)) &&
+ (ic->seq >= fseq && ic->seq <= toseq))
+ return FALSE;
+ }
+ return TRUE;
+}
+
+/*-----------------------------------------------------------------*/
+/* computeSpillable - given a point find the spillable live ranges */
+/*-----------------------------------------------------------------*/
+static bitVect *computeSpillable (iCode * ic) {
+ bitVect *spillable;
+
+ /* spillable live ranges are those that are live at this
+ point . the following categories need to be subtracted
+ from this set.
+ a) - those that are already spilt
+ b) - if being used by this one
+ c) - defined by this one */
+
+ spillable = bitVectCopy (ic->rlive);
+ spillable =
+ bitVectCplAnd (spillable, _G.spiltSet); /* those already spilt */
+ spillable =
+ bitVectCplAnd (spillable, ic->uses); /* used in this one */
+ bitVectUnSetBit (spillable, ic->defKey); /* defined by this one */
+ spillable = bitVectIntersect (spillable, _G.regAssigned);
+ return spillable;
+
+}
+
+/*-----------------------------------------------------------------*/
+/* noSpilLoc - return true if a variable has no spil location */
+/*-----------------------------------------------------------------*/
+static int
+noSpilLoc (symbol * sym, eBBlock * ebp, iCode * ic)
+{
+ return (sym->usl.spillLoc ? 0 : 1);
+}
+
+/*-----------------------------------------------------------------*/
+/* hasSpilLoc - will return 1 if the symbol has spil location */
+/*-----------------------------------------------------------------*/
+static int
+hasSpilLoc (symbol * sym, eBBlock * ebp, iCode * ic)
+{
+ return (sym->usl.spillLoc ? 1 : 0);
+}
+
+/*-----------------------------------------------------------------*/
+/* hasSpilLocnoUptr - will return 1 if the symbol has spil location */
+/* but is not used as a pointer */
+/*-----------------------------------------------------------------*/
+static int
+hasSpilLocnoUptr (symbol * sym, eBBlock * ebp, iCode * ic)
+{
+ return ((sym->usl.spillLoc && !sym->uptr) ? 1 : 0);
+}
+
+/*-----------------------------------------------------------------*/
+/* rematable - will return 1 if the remat flag is set */
+/*-----------------------------------------------------------------*/
+static int
+rematable (symbol * sym, eBBlock * ebp, iCode * ic)
+{
+ return sym->remat;
+}
+
+/*-----------------------------------------------------------------*/
+/* notUsedInBlock - not used in this block */
+/*-----------------------------------------------------------------*/
+static int
+notUsedInBlock (symbol * sym, eBBlock * ebp, iCode * ic)
+{
+ return (!bitVectBitsInCommon (sym->defs, ebp->usesDefs) &&
+ allDefsOutOfRange (sym->defs, ebp->fSeq, ebp->lSeq));
+/* return (!bitVectBitsInCommon(sym->defs,ebp->usesDefs)); */
+}
+
+/*-----------------------------------------------------------------*/
+/* notUsedInRemaining - not used or defined in remain of the block */
+/*-----------------------------------------------------------------*/
+static int
+notUsedInRemaining (symbol * sym, eBBlock * ebp, iCode * ic)
+{
+ return ((usedInRemaining (operandFromSymbol (sym), ic) ? 0 : 1) &&
+ allDefsOutOfRange (sym->defs, ebp->fSeq, ebp->lSeq));
+}
+
+/*-----------------------------------------------------------------*/
+/* allLRs - return true for all */
+/*-----------------------------------------------------------------*/
+static int
+allLRs (symbol * sym, eBBlock * ebp, iCode * ic)
+{
+ return 1;
+}
+
+/*-----------------------------------------------------------------*/
+/* liveRangesWith - applies function to a given set of live range */
+/*-----------------------------------------------------------------*/
+static set *
+liveRangesWith (bitVect * lrs, int (func) (symbol *, eBBlock *, iCode *),
+ eBBlock * ebp, iCode * ic)
+{
+ set *rset = NULL;
+ int i;
+
+ if (!lrs || !lrs->size)
+ return NULL;
+
+ for (i = 1; i < lrs->size; i++)
+ {
+ symbol *sym;
+ if (!bitVectBitValue (lrs, i))
+ continue;
+
+ /* if we don't find it in the live range
+ hash table we are in serious trouble */
+ if (!(sym = hTabItemWithKey (liveRanges, i)))
+ {
+ werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
+ "liveRangesWith could not find liveRange");
+ exit (1);
+ }
+
+ if (func (sym, ebp, ic) && bitVectBitValue (_G.regAssigned, sym->key))
+ addSetHead (&rset, sym);
+ }
+
+ return rset;
+}
+
+
+/*-----------------------------------------------------------------*/
+/* leastUsedLR - given a set determines which is the least used */
+/*-----------------------------------------------------------------*/
+static symbol *
+leastUsedLR (set * sset)
+{
+ symbol *sym = NULL, *lsym = NULL;
+
+ sym = lsym = setFirstItem (sset);
+
+ if (!lsym)
+ return NULL;
+
+ for (; lsym; lsym = setNextItem (sset))
+ {
+
+ /* if usage is the same then prefer
+ the spill the smaller of the two */
+ if (lsym->used == sym->used)
+ if (getSize (lsym->type) < getSize (sym->type))
+ sym = lsym;
+
+ /* if less usage */
+ if (lsym->used < sym->used)
+ sym = lsym;
+
+ }
+
+ setToNull ((void **) &sset);
+ sym->blockSpil = 0;
+ return sym;
+}
+
+/*-----------------------------------------------------------------*/
+/* noOverLap - will iterate through the list looking for over lap */
+/*-----------------------------------------------------------------*/
+static int
+noOverLap (set * itmpStack, symbol * fsym)
+{
+ symbol *sym;
+
+
+ for (sym = setFirstItem (itmpStack); sym;
+ sym = setNextItem (itmpStack))
+ {
+ if (bitVectBitValue(sym->clashes,fsym->key)) return 0;
+ }
+
+ return 1;
+}
+
+/*-----------------------------------------------------------------*/
+/* isFree - will return 1 if the a free spil location is found */
+/*-----------------------------------------------------------------*/
+static
+DEFSETFUNC (isFree)
+{
+ symbol *sym = item;
+ V_ARG (symbol **, sloc);
+ V_ARG (symbol *, fsym);
+
+ /* if already found */
+ if (*sloc)
+ return 0;
+
+ /* if it is free && and the itmp assigned to
+ this does not have any overlapping live ranges
+ with the one currently being assigned and
+ the size can be accomodated */
+ if (sym->isFree &&
+ noOverLap (sym->usl.itmpStack, fsym) &&
+ getSize (sym->type) >= getSize (fsym->type))
+ {
+ *sloc = sym;
+ return 1;
+ }
+
+ return 0;
+}
+
+/*-----------------------------------------------------------------*/
+/* createStackSpil - create a location on the stack to spil */
+/*-----------------------------------------------------------------*/
+static symbol *
+createStackSpil (symbol * sym)
+{
+ symbol *sloc = NULL;
+ int useXstack, model;
+
+ char slocBuffer[30];
+
+ fprintf (stderr, " createStackSpil: %s\n", sym->name);
+
+ /* first go try and find a free one that is already
+ existing on the stack */
+ if (applyToSet (_G.stackSpil, isFree, &sloc, sym))
+ {
+ /* found a free one : just update & return */
+ sym->usl.spillLoc = sloc;
+ sym->stackSpil = 1;
+ sloc->isFree = 0;
+ addSetHead (&sloc->usl.itmpStack, sym);
+ return sym;
+ }
+
+ /* could not then have to create one , this is the hard part
+ we need to allocate this on the stack : this is really a
+ hack!! but cannot think of anything better at this time */
+
+ if (sprintf (slocBuffer, "sloc%d", _G.slocNum++) >= sizeof (slocBuffer))
+ {
+ fprintf (stderr, "***Internal error: slocBuffer overflowed: %s:%d\n",
+ __FILE__, __LINE__);
+ exit (1);
+ }
+
+ sloc = newiTemp (slocBuffer);
+
+ /* set the type to the spilling symbol */
+ sloc->type = copyLinkChain (sym->type);
+ sloc->etype = getSpec (sloc->type);
+ SPEC_SCLS (sloc->etype) = S_STACK;
+ SPEC_EXTR (sloc->etype) = 0;
+ SPEC_STAT (sloc->etype) = 0;
+ SPEC_VOLATILE(sloc->etype) = 0;
+ SPEC_ABSA(sloc->etype) = 0;
+
+ /* we don't allow it to be allocated`
+ onto the external stack since : so we
+ temporarily turn it off ; we also
+ turn off memory model to prevent
+ the spil from going to the external storage
+ */
+
+ useXstack = options.useXstack;
+ model = options.model;
+/* noOverlay = options.noOverlay; */
+/* options.noOverlay = 1; */
+ options.model = options.useXstack = 0;
+
+ allocLocal (sloc);
+
+ options.useXstack = useXstack;
+ options.model = model;
+/* options.noOverlay = noOverlay; */
+ sloc->isref = 1; /* to prevent compiler warning */
+
+ /* if it is on the stack then update the stack */
+ if (IN_STACK (sloc->etype))
+ {
+ currFunc->stack += getSize (sloc->type);
+ _G.stackExtend += getSize (sloc->type);
+ }
+ else
+ _G.dataExtend += getSize (sloc->type);
+
+ /* add it to the _G.stackSpil set */
+ addSetHead (&_G.stackSpil, sloc);
+ sym->usl.spillLoc = sloc;
+ sym->stackSpil = 1;
+
+ /* add it to the set of itempStack set
+ of the spill location */
+ addSetHead (&sloc->usl.itmpStack, sym);
+ return sym;
+}
+
+/*-----------------------------------------------------------------*/
+/* spillThis - spils a specific operand */
+/*-----------------------------------------------------------------*/
+static void
+spillThis (symbol * sym)
+{
+ int i;
+
+ fprintf (stderr, " spillThis: %s\n", sym->name);
+
+ /* if this is rematerializable or has a spillLocation
+ we are okay, else we need to create a spillLocation
+ for it */
+ if (!(sym->remat || sym->usl.spillLoc))
+ createStackSpil (sym);
+
+
+ /* mark it has spilt & put it in the spilt set */
+ sym->isspilt = sym->spillA = 1;
+ _G.spiltSet = bitVectSetBit (_G.spiltSet, sym->key);
+
+ bitVectUnSetBit (_G.regAssigned, sym->key);
+ bitVectUnSetBit (_G.totRegAssigned, sym->key);
+
+ for (i = 0; i < sym->nRegs; i++)
+
+ if (sym->regs[i])
+ {
+ freeReg (sym->regs[i], FALSE);
+ }
+
+ if (sym->usl.spillLoc && !sym->remat)
+ sym->usl.spillLoc->allocreq++;
+ return;
+}
+
+/*-----------------------------------------------------------------*/
+/* selectSpil - select a iTemp to spil : rather a simple procedure */
+/*-----------------------------------------------------------------*/
+static symbol *
+selectSpil (iCode * ic, eBBlock * ebp, symbol * forSym)
+{
+ bitVect *lrcs = NULL;
+ set *selectS;
+ symbol *sym;
+
+ /* get the spillable live ranges */
+ lrcs = computeSpillable (ic);
+
+ /* get all live ranges that are rematerizable */
+ if ((selectS = liveRangesWith (lrcs, rematable, ebp, ic)))
+ {
+ /* return the least used of these */
+ return leastUsedLR (selectS);
+ }
+
+ /* if the symbol is local to the block then */
+ if (forSym->liveTo < ebp->lSeq)
+ {
+
+ /* check if there are any live ranges allocated
+ to registers that are not used in this block */
+ if (!_G.blockSpil && (selectS = liveRangesWith (lrcs, notUsedInBlock, ebp, ic)))
+ {
+ sym = leastUsedLR (selectS);
+ /* if this is not rematerializable */
+ if (!sym->remat)
+ {
+ _G.blockSpil++;
+ sym->blockSpil = 1;
+ }
+ return sym;
+ }
+
+ /* check if there are any live ranges that not
+ used in the remainder of the block */
+ if (!_G.blockSpil && (selectS = liveRangesWith (lrcs, notUsedInRemaining, ebp, ic)))
+ {
+ sym = leastUsedLR (selectS);
+ if (sym != forSym)
+ {
+ if (!sym->remat)
+ {
+ sym->remainSpil = 1;
+ _G.blockSpil++;
+ }
+ return sym;
+ }
+ }
+ }
+
+ /* find live ranges with spillocation && not used as pointers */
+ if ((selectS = liveRangesWith (lrcs, hasSpilLocnoUptr, ebp, ic)))
+ {
+
+ sym = leastUsedLR (selectS);
+ /* mark this as allocation required */
+ sym->usl.spillLoc->allocreq++;
+ return sym;
+ }
+
+ /* find live ranges with spillocation */
+ if ((selectS = liveRangesWith (lrcs, hasSpilLoc, ebp, ic)))
+ {
+
+ sym = leastUsedLR (selectS);
+ sym->usl.spillLoc->allocreq++;
+ return sym;
+ }
+
+ /* couldn't find then we need to create a spil
+ location on the stack , for which one? the least
+ used ofcourse */
+ if ((selectS = liveRangesWith (lrcs, noSpilLoc, ebp, ic)))
+ {
+
+ /* return a created spil location */
+ sym = createStackSpil (leastUsedLR (selectS));
+ sym->usl.spillLoc->allocreq++;
+ return sym;
+ }
+
+ /* this is an extreme situation we will spill
+ this one : happens very rarely but it does happen */
+ spillThis (forSym);
+ return forSym;
+}
+
+/*-----------------------------------------------------------------*/
+/* spillSomething - spil some variable & mark registers as free */
+/*-----------------------------------------------------------------*/
+static bool
+spillSomething (iCode * ic, eBBlock * ebp, symbol * forSym)
+{
+ symbol *ssym;
+ int i;
+
+ /* get something we can spil */
+ ssym = selectSpil (ic, ebp, forSym);
+
+ fprintf (stderr, " spillSomething: spilling %s\n", ssym->name);
+
+ /* mark it as spilt */
+ ssym->isspilt = ssym->spillA = 1;
+ _G.spiltSet = bitVectSetBit (_G.spiltSet, ssym->key);
+
+ /* mark it as not register assigned &
+ take it away from the set */
+ bitVectUnSetBit (_G.regAssigned, ssym->key);
+ bitVectUnSetBit (_G.totRegAssigned, ssym->key);
+
+ /* mark the registers as free */
+ for (i = 0; i < ssym->nRegs; i++) {
+ if (ssym->regs[i]) {
+ freeReg (ssym->regs[i], FALSE);
+ // dont NULL ssym->regs[i], it might be used later
+ }
+ }
+
+ /* if this was a block level spil then insert push & pop
+ at the start & end of block respectively */
+ if (ssym->blockSpil)
+ {
+ iCode *nic = newiCode (IPUSH, operandFromSymbol (ssym), NULL);
+ /* add push to the start of the block */
+ addiCodeToeBBlock (ebp, nic, (ebp->sch->op == LABEL ?
+ ebp->sch->next : ebp->sch));
+ nic = newiCode (IPOP, operandFromSymbol (ssym), NULL);
+ /* add pop to the end of the block */
+ addiCodeToeBBlock (ebp, nic, NULL);
+ }
+
+ /* if spilt because not used in the remainder of the
+ block then add a push before this instruction and
+ a pop at the end of the block */
+ if (ssym->remainSpil)
+ {
+
+ iCode *nic = newiCode (IPUSH, operandFromSymbol (ssym), NULL);
+ /* add push just before this instruction */
+ addiCodeToeBBlock (ebp, nic, ic);
+
+ nic = newiCode (IPOP, operandFromSymbol (ssym), NULL);
+ /* add pop to the end of the block */
+ addiCodeToeBBlock (ebp, nic, NULL);
+ }
+
+ if (ssym == forSym)
+ return FALSE;
+ else
+ return TRUE;
+}
+
+/*-----------------------------------------------------------------*/
+/* getRegPtr - will try for PTR if not a GPR type if not spil */
+/*-----------------------------------------------------------------*/
+static bool getRegPtr (iCode * ic, eBBlock * ebp, symbol * sym, short offset) {
+
+ fprintf (stderr, "getRegPtr: %s ", sym->name);
+ printTypeChain(sym->type, stderr);
+ fprintf (stderr, "\n");
+
+tryAgain:
+ /* try for a ptr type */
+ if (allocReg (getSize(sym->type), REG_PTR, sym, offset, FALSE))
+ return TRUE;
+
+ /* try for gpr type */
+ if (xa51HasGprRegs && allocReg (getSize(sym->type),
+ REG_GPR, sym, offset, FALSE))
+ return TRUE;
+
+ /* we have to spil */
+ if (!spillSomething (ic, ebp, sym))
+ return FALSE;
+
+ /* this looks like an infinite loop but
+ in really selectSpil will abort */
+ goto tryAgain;
+}
+
+/*-----------------------------------------------------------------*/
+/* getRegGpr - will try for GPR if not spil */
+/*-----------------------------------------------------------------*/
+static bool getRegGpr (iCode * ic, eBBlock * ebp, symbol * sym, short offset) {
+
+ fprintf (stderr, "getRegGpr: %s ", sym->name);
+ printTypeChain(sym->type, stderr);
+ fprintf (stderr, "\n");
+
+tryAgain:
+ /* try for gpr type */
+ if (xa51HasGprRegs && allocReg (getSize(sym->type),
+ REG_GPR, sym, offset, FALSE))
+ return TRUE;
+
+ if (allocReg (getSize(sym->type), REG_PTR, sym, offset, FALSE))
+ return TRUE;
+
+ /* we have to spil */
+ if (!spillSomething (ic, ebp, sym))
+ return FALSE;
+
+ /* this looks like an infinite loop but
+ in really selectSpil will abort */
+ goto tryAgain;
+}
+
+/*-----------------------------------------------------------------*/
+/* deassignLRs - check the live to and if they have registers & are */
+/* not spilt then free up the registers */
+/*-----------------------------------------------------------------*/
+static void
+deassignLRs (iCode * ic, eBBlock * ebp)
+{
+ symbol *sym;
+ int k;
+
+ for (sym = hTabFirstItem (liveRanges, &k); sym;
+ sym = hTabNextItem (liveRanges, &k))
+ {
+ /* if it does not end here */
+ if (sym->liveTo > ic->seq)
+ continue;
+
+ /* if it was spilt on stack then we can
+ mark the stack spil location as free */
+ if (sym->isspilt)
+ {
+ if (sym->stackSpil)
+ {
+ sym->usl.spillLoc->isFree = 1;
+ sym->stackSpil = 0;
+ }
+ continue;
+ }
+
+ if (!bitVectBitValue (_G.regAssigned, sym->key))
+ continue;
+
+ if (sym->nRegs) {
+ int i;
+
+ bitVectUnSetBit (_G.regAssigned, sym->key);
+
+ /* free the regs */
+ for (i=0; i < sym->nRegs; i++) {
+ freeReg (sym->regs[i], FALSE);
+ }
+ }
+ }
+}
+
+/*-----------------------------------------------------------------*/
+/* willCauseSpill - determines if allocating will cause a spill */
+/*-----------------------------------------------------------------*/
+static bool willCauseSpill (symbol *sym) {
+ int i;
+ // do it the rude way
+ if (allocReg (getSize(sym->type), sym->regType, sym, 0, TRUE) ||
+ allocReg (getSize(sym->type), sym->regType==REG_PTR?REG_GPR:REG_PTR,
+ sym, 0, TRUE)) {
+ // so we can, but we won't
+ for (i=0; i<sym->nRegs; i++) {
+ freeReg (sym->regs[i], TRUE);
+ sym->regs[i]=NULL;
+ }
+ return FALSE;
+ }
+ fprintf (stderr, " %s will cause a spill\n", sym->name);
+ return TRUE;
+}
+
+/*-----------------------------------------------------------------*/
+/* positionRegs - the allocator can allocate same registers to res- */
+/* ult and operand, if this happens make sure they are in the same */
+/* position as the operand otherwise chaos results */
+/*-----------------------------------------------------------------*/
+static int
+positionRegs (symbol * result, symbol * opsym)
+{
+ int count = min (result->nRegs, opsym->nRegs);
+ int i, j = 0, shared = 0;
+ int change = 0;
+
+ /* if the result has been spilt then cannot share */
+ if (opsym->isspilt)
+ return 0;
+again:
+ shared = 0;
+ /* first make sure that they actually share */
+ for (i = 0; i < count; i++)
+ {
+ for (j = 0; j < count; j++)
+ {
+ if (result->regs[i] == opsym->regs[j] && i != j)
+ {
+ shared = 1;
+ goto xchgPositions;
+ }
+ }
+ }
+xchgPositions:
+ if (shared)
+ {
+ regs *tmp = result->regs[i];
+ result->regs[i] = result->regs[j];
+ result->regs[j] = tmp;
+ change ++;
+ goto again;
+ }
+ return change;
+}
+
+/*-----------------------------------------------------------------*/
+/* serialRegAssign - serially allocate registers to the variables */
+/*-----------------------------------------------------------------*/
+static void
+serialRegAssign (eBBlock ** ebbs, int count)
+{
+ int i;
+
+ /* for all blocks */
+ for (i = 0; i < count; i++) {
+
+ iCode *ic;
+
+ if (ebbs[i]->noPath &&
+ (ebbs[i]->entryLabel != entryLabel &&
+ ebbs[i]->entryLabel != returnLabel))
+ continue;
+
+ /* of all instructions do */
+ for (ic = ebbs[i]->sch; ic; ic = ic->next) {
+
+ /* if result is present && is a true symbol */
+ if (IC_RESULT (ic) && ic->op != IFX &&
+ IS_TRUE_SYMOP (IC_RESULT (ic)))
+ OP_SYMBOL (IC_RESULT (ic))->allocreq++;
+
+ /* take away registers from live
+ ranges that end at this instruction */
+ deassignLRs (ic, ebbs[i]);
+
+ /* some don't need registers */
+ if (SKIP_IC2 (ic) ||
+ ic->op == JUMPTABLE ||
+ ic->op == IFX ||
+ ic->op == IPUSH ||
+ ic->op == IPOP ||
+ (IC_RESULT (ic) && POINTER_SET (ic)))
+ continue;
+
+ /* now we need to allocate registers
+ only for the result */
+ if (IC_RESULT (ic)) {
+ symbol *sym = OP_SYMBOL (IC_RESULT (ic));
+ bitVect *spillable;
+ int willCS;
+
+ /* if it does not need or is spilt
+ or is already assigned to registers
+ or will not live beyond this instructions */
+ if (!sym->nRegs ||
+ sym->isspilt ||
+ bitVectBitValue (_G.regAssigned, sym->key) ||
+ sym->liveTo <= ic->seq)
+ continue;
+
+ /* if some liverange has been spilt at the block level
+ and this one live beyond this block then spil this
+ to be safe */
+ if (_G.blockSpil && sym->liveTo > ebbs[i]->lSeq) {
+ spillThis (sym);
+ continue;
+ }
+ /* if trying to allocate this will cause
+ a spill and there is nothing to spill
+ or this one is rematerializable then
+ spill this one */
+ willCS = willCauseSpill (sym);
+ spillable = computeSpillable (ic);
+ if (sym->remat || (willCS && bitVectIsZero (spillable))) {
+ spillThis (sym);
+ continue;
+ }
+
+ /* if it has a spillocation & is used less than
+ all other live ranges then spill this */
+ if (willCS) {
+ if (sym->usl.spillLoc) {
+ symbol *leastUsed = leastUsedLR (liveRangesWith (spillable,
+ allLRs, ebbs[i], ic));
+ if (leastUsed && leastUsed->used > sym->used) {
+ spillThis (sym);
+ continue;
+ }
+ } else {
+ /* if none of the liveRanges have a spillLocation then better
+ to spill this one than anything else already assigned to registers */
+ if (liveRangesWith(spillable,noSpilLoc,ebbs[i],ic)) {
+ /* if this is local to this block then we might find a block spil */
+ if (!(sym->liveFrom >= ebbs[i]->fSeq && sym->liveTo <= ebbs[i]->lSeq)) {
+ spillThis (sym);
+ continue;
+ }
+ }
+ }
+ }
+
+ /* else we assign registers to it */
+ _G.regAssigned = bitVectSetBit (_G.regAssigned, sym->key);
+ _G.totRegAssigned = bitVectSetBit (_G.totRegAssigned, sym->key);
+
+ if (sym->regType == REG_PTR)
+ getRegPtr (ic, ebbs[i], sym, 0);
+ else
+ getRegGpr (ic, ebbs[i], sym, 0);
+
+ /* if it shares registers with operands make sure
+ that they are in the same position */
+ if (IC_LEFT (ic) && IS_SYMOP (IC_LEFT (ic)) &&
+ OP_SYMBOL (IC_LEFT (ic))->nRegs && ic->op != '=') {
+ positionRegs (OP_SYMBOL (IC_RESULT (ic)),
+ OP_SYMBOL (IC_LEFT (ic)));
+ }
+ /* do the same for the right operand */
+ if (IC_RIGHT (ic) && IS_SYMOP (IC_RIGHT (ic)) &&
+ OP_SYMBOL (IC_RIGHT (ic))->nRegs) {
+ positionRegs (OP_SYMBOL (IC_RESULT (ic)),
+ OP_SYMBOL (IC_RIGHT (ic)));
+ }
+ }
+ }
+ }
+}
+
+/*-----------------------------------------------------------------*/
+/* rUmaskForOp :- returns register mask for an operand */
+/*-----------------------------------------------------------------*/
+bitVect *xa51_rUmaskForOp (operand * op) {
+ bitVect *rumask;
+ symbol *sym;
+ int j;
+
+ /* only temporaries are assigned registers */
+ if (!IS_ITEMP (op))
+ return NULL;
+
+ sym = OP_SYMBOL (op);
+
+ /* if spilt or no registers assigned to it
+ then nothing */
+ if (sym->isspilt || !sym->nRegs || !sym->regs[0])
+ return NULL;
+
+ rumask = newBitVect (xa51_nRegs);
+
+ for (j = 0; j < sym->nRegs; j++) {
+ rumask = bitVectSetBit (rumask,
+ sym->regs[j]->rIdx);
+ }
+ return rumask;
+}
+
+/*-----------------------------------------------------------------*/
+/* regsUsedIniCode :- returns bit vector of registers used in iCode */
+/*-----------------------------------------------------------------*/
+static bitVect *
+regsUsedIniCode (iCode * ic)
+{
+ bitVect *rmask = newBitVect (xa51_nRegs);
+
+ /* do the special cases first */
+ if (ic->op == IFX)
+ {
+ rmask = bitVectUnion (rmask,
+ xa51_rUmaskForOp (IC_COND (ic)));
+ goto ret;
+ }
+
+ /* for the jumptable */
+ if (ic->op == JUMPTABLE)
+ {
+ rmask = bitVectUnion (rmask,
+ xa51_rUmaskForOp (IC_JTCOND (ic)));
+
+ goto ret;
+ }
+
+ /* of all other cases */
+ if (IC_LEFT (ic))
+ rmask = bitVectUnion (rmask,
+ xa51_rUmaskForOp (IC_LEFT (ic)));
+
+
+ if (IC_RIGHT (ic))
+ rmask = bitVectUnion (rmask,
+ xa51_rUmaskForOp (IC_RIGHT (ic)));
+
+ if (IC_RESULT (ic))
+ rmask = bitVectUnion (rmask,
+ xa51_rUmaskForOp (IC_RESULT (ic)));
+
+ret:
+ return rmask;
+}
+
+/*-----------------------------------------------------------------*/
+/* createRegMask - for each instruction will determine the regsUsed */
+/*-----------------------------------------------------------------*/
+static void
+createRegMask (eBBlock ** ebbs, int count)
+{
+ int i;
+
+ /* for all blocks */
+ for (i = 0; i < count; i++)
+ {
+ iCode *ic;
+
+ if (ebbs[i]->noPath &&
+ (ebbs[i]->entryLabel != entryLabel &&
+ ebbs[i]->entryLabel != returnLabel))
+ continue;
+
+ /* for all instructions */
+ for (ic = ebbs[i]->sch; ic; ic = ic->next)
+ {
+
+ int j;
+
+ if (SKIP_IC2 (ic) || !ic->rlive)
+ continue;
+
+ /* first mark the registers used in this
+ instruction */
+ ic->rUsed = regsUsedIniCode (ic);
+ _G.funcrUsed = bitVectUnion (_G.funcrUsed, ic->rUsed);
+
+ /* now create the register mask for those
+ registers that are in use : this is a
+ super set of ic->rUsed */
+ ic->rMask = newBitVect (xa51_nRegs + 1);
+
+ /* for all live Ranges alive at this point */
+ for (j = 1; j < ic->rlive->size; j++)
+ {
+ symbol *sym;
+ int k;
+
+ /* if not alive then continue */
+ if (!bitVectBitValue (ic->rlive, j))
+ continue;
+
+ /* find the live range we are interested in */
+ if (!(sym = hTabItemWithKey (liveRanges, j)))
+ {
+ werror (E_INTERNAL_ERROR, __FILE__, __LINE__,
+ "createRegMask cannot find live range");
+ exit (0);
+ }
+
+ /* if no register assigned to it */
+ if (!sym->nRegs || sym->isspilt)
+ continue;
+
+ /* for all the registers allocated to it */
+ for (k = 0; k < sym->nRegs; k++)
+ if (sym->regs[k])
+ ic->rMask =
+ bitVectSetBit (ic->rMask, sym->regs[k]->rIdx);
+ }
+ }
+ }
+}
+
+/*-----------------------------------------------------------------*/
+/* rematStr - returns the rematerialized string for a remat var */
+/*-----------------------------------------------------------------*/
+static char *
+rematStr (symbol * sym)
+{
+ char *s = buffer;
+ iCode *ic = sym->rematiCode;
+
+ while (1)
+ {
+
+ /* if plus or minus print the right hand side */
+ if (ic->op == '+' || ic->op == '-')
+ {
+ sprintf (s, "0x%04x %c ", (int) operandLitValue (IC_RIGHT (ic)),
+ ic->op);
+ s += strlen (s);
+ ic = OP_SYMBOL (IC_LEFT (ic))->rematiCode;
+ continue;
+ }
+
+ /* cast then continue */
+ if (IS_CAST_ICODE(ic)) {
+ ic = OP_SYMBOL (IC_RIGHT (ic))->rematiCode;
+ continue;
+ }
+ /* we reached the end */
+ sprintf (s, "%s", OP_SYMBOL (IC_LEFT (ic))->rname);
+ break;
+ }
+
+ return buffer;
+}
+
+/*-----------------------------------------------------------------*/
+/* regTypeNum - computes the type & number of registers required */
+/*-----------------------------------------------------------------*/
+static void
+regTypeNum (eBBlock *ebbs)
+{
+ symbol *sym;
+ int k;
+ iCode *ic;
+
+ /* for each live range do */
+ for (sym = hTabFirstItem (liveRanges, &k); sym;
+ sym = hTabNextItem (liveRanges, &k))
+ {
+
+ /* if used zero times then no registers needed */
+ if ((sym->liveTo - sym->liveFrom) == 0)
+ continue;
+
+
+ /* if the live range is a temporary */
+ if (sym->isitmp)
+ {
+
+ /* if the type is marked as a conditional */
+ if (sym->regType == REG_CND)
+ continue;
+
+ /* if used in return only then we don't
+ need registers */
+#if 0 // not yet
+ if (sym->ruonly || sym->accuse)
+ {
+ if (IS_AGGREGATE (sym->type) || sym->isptr)
+ sym->type = aggrToPtr (sym->type, FALSE);
+ continue;
+ }
+#endif
+
+ /* if the symbol has only one definition &
+ that definition is a get_pointer and the
+ pointer we are getting is rematerializable and
+ in "data" space */
+
+ if (bitVectnBitsOn (sym->defs) == 1 &&
+ (ic = hTabItemWithKey (iCodehTab,
+ bitVectFirstBit (sym->defs))) &&
+ POINTER_GET (ic) &&
+ !sym->noSpilLoc &&
+ !IS_BITVAR (sym->etype))
+ {
+
+
+ /* if remat in data space */
+ if (OP_SYMBOL (IC_LEFT (ic))->remat &&
+ !IS_CAST_ICODE(OP_SYMBOL (IC_LEFT (ic))->rematiCode) &&
+ DCL_TYPE (aggrToPtr (sym->type, FALSE)) == POINTER)
+ {
+ /* create a psuedo symbol & force a spil */
+ symbol *psym = newSymbol (rematStr (OP_SYMBOL (IC_LEFT (ic))), 1);
+ psym->type = sym->type;
+ psym->etype = sym->etype;
+ strcpy (psym->rname, psym->name);
+ sym->isspilt = 1;
+ sym->usl.spillLoc = psym;
+#if 0 // an alternative fix for bug #480076
+ /* now this is a useless assignment to itself */
+ remiCodeFromeBBlock (ebbs, ic);
+#else
+ /* now this really is an assignment to itself, make it so;
+ it will be optimized out later */
+ ic->op='=';
+ IC_RIGHT(ic)=IC_RESULT(ic);
+ IC_LEFT(ic)=NULL;
+#endif
+ continue;
+ }
+
+ /* if in data space or idata space then try to
+ allocate pointer register */
+
+ }
+
+ /* if not then we require registers */
+#if 0
+ sym->nRegs = ((IS_AGGREGATE (sym->type) || sym->isptr) ?
+ getSize (sym->type = aggrToPtr (sym->type, FALSE)) :
+ getSize (sym->type));
+#else
+ {
+ int size=((IS_AGGREGATE (sym->type) || sym->isptr) ?
+ getSize (sym->type = aggrToPtr (sym->type, FALSE)) :
+ getSize (sym->type));
+ switch (size)
+ {
+ case 1: // byte
+ case 2: // word or pointer
+ sym->nRegs=1;
+ break;
+ case 3: // generic pointer
+ sym->nRegs=2;
+ break;
+ case 4: // dword or float
+ sym->nRegs=2;
+ break;
+ default:
+ fprintf (stderr, "regTypeNum: unknown size\n");
+ exit (1);
+ }
+ }
+#endif
+
+ if (sym->nRegs > 4)
+ {
+ fprintf (stderr, "allocated more than 4 or 0 registers for type ");
+ printTypeChain (sym->type, stderr);
+ fprintf (stderr, "\n");
+ }
+
+ /* determine the type of register required */
+ if (IS_PTR (sym->type))
+ sym->regType = REG_PTR;
+ else
+ sym->regType = REG_GPR;
+
+ }
+ else
+ /* for the first run we don't provide */
+ /* registers for true symbols we will */
+ /* see how things go */
+ sym->nRegs = 0;
+ }
+
+}
+
+/*-----------------------------------------------------------------*/
+/* deallocStackSpil - this will set the stack pointer back */
+/*-----------------------------------------------------------------*/
+static
+DEFSETFUNC (deallocStackSpil)
+{
+ symbol *sym = item;
+
+ deallocLocal (sym);
+ return 0;
+}
+
+/*-----------------------------------------------------------------*/
+/* packRegsForAssign - register reduction for assignment */
+/*-----------------------------------------------------------------*/
+static int
+packRegsForAssign (iCode * ic, eBBlock * ebp)
+{
+ iCode *dic, *sic;
+
+ if (!IS_ITEMP (IC_RIGHT (ic)) ||
+ OP_LIVETO (IC_RIGHT (ic)) > ic->seq) {
+ return 0;
+ }
+
+ /* find the definition of iTempNN scanning backwards */
+ for (dic = ic->prev; dic; dic = dic->prev) {
+
+ /* if there is a function call then don't pack it */
+ if ((dic->op == CALL || dic->op == PCALL)) {
+ dic = NULL;
+ break;
+ }
+
+ if (SKIP_IC2 (dic))
+ continue;
+
+ if (IS_SYMOP (IC_RESULT (dic)) &&
+ IC_RESULT (dic)->key == IC_RIGHT (ic)->key) {
+ break;
+ }
+
+ }
+
+ if (!dic)
+ return 0; /* did not find */
+
+ /* found the definition */
+ /* replace the result with the result of */
+ /* this assignment and remove this assignment */
+ bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
+ IC_RESULT (dic) = IC_RESULT (ic);
+
+ if (IS_ITEMP (IC_RESULT (dic)) &&
+ OP_SYMBOL (IC_RESULT (dic))->liveFrom > dic->seq)
+ {
+ OP_SYMBOL (IC_RESULT (dic))->liveFrom = dic->seq;
+ }
+ /* delete from liverange table also
+ delete from all the points inbetween and the new
+ one */
+ for (sic = dic; sic != ic; sic = sic->next)
+ {
+ bitVectUnSetBit (sic->rlive, IC_RESULT (ic)->key);
+ if (IS_ITEMP (IC_RESULT (dic)))
+ bitVectSetBit (sic->rlive, IC_RESULT (dic)->key);
+ }
+
+ remiCodeFromeBBlock (ebp, ic);
+ bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
+ hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
+ OP_DEFS (IC_RESULT (dic)) = bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
+ return 1;
+
+}
+
+/*-----------------------------------------------------------------*/
+/* findAssignToSym : scanning backwards looks for first assig found */
+/*-----------------------------------------------------------------*/
+static iCode *
+findAssignToSym (operand * op, iCode * ic)
+{
+ iCode *dic;
+
+ for (dic = ic->prev; dic; dic = dic->prev)
+ {
+
+ /* if definition by assignment */
+ if (dic->op == '=' &&
+ !POINTER_SET (dic) &&
+ IC_RESULT (dic)->key == op->key
+/* && IS_TRUE_SYMOP(IC_RIGHT(dic)) */
+ )
+ {
+
+ /* we are interested only if defined in far space */
+ /* or in stack space in case of + & - */
+
+ /* if assigned to a non-symbol then return
+ FALSE */
+ if (!IS_SYMOP (IC_RIGHT (dic)))
+ return NULL;
+
+ /* if the symbol is in far space then
+ we should not */
+ if (isOperandInFarSpace (IC_RIGHT (dic)))
+ return NULL;
+
+ /* for + & - operations make sure that
+ if it is on the stack it is the same
+ as one of the three operands */
+ if ((ic->op == '+' || ic->op == '-') &&
+ OP_SYMBOL (IC_RIGHT (dic))->onStack)
+ {
+
+ if (IC_RESULT (ic)->key != IC_RIGHT (dic)->key &&
+ IC_LEFT (ic)->key != IC_RIGHT (dic)->key &&
+ IC_RIGHT (ic)->key != IC_RIGHT (dic)->key)
+ return NULL;
+ }
+
+ break;
+
+ }
+
+ /* if we find an usage then we cannot delete it */
+ if (IC_LEFT (dic) && IC_LEFT (dic)->key == op->key)
+ return NULL;
+
+ if (IC_RIGHT (dic) && IC_RIGHT (dic)->key == op->key)
+ return NULL;
+
+ if (POINTER_SET (dic) && IC_RESULT (dic)->key == op->key)
+ return NULL;
+ }
+
+ /* now make sure that the right side of dic
+ is not defined between ic & dic */
+ if (dic)
+ {
+ iCode *sic = dic->next;
+
+ for (; sic != ic; sic = sic->next)
+ if (IC_RESULT (sic) &&
+ IC_RESULT (sic)->key == IC_RIGHT (dic)->key)
+ return NULL;
+ }
+
+ return dic;
+
+
+}
+
+/*-----------------------------------------------------------------*/
+/* packRegsForSupport :- reduce some registers for support calls */
+/*-----------------------------------------------------------------*/
+static int
+packRegsForSupport (iCode * ic, eBBlock * ebp)
+{
+ int change = 0;
+ iCode *dic, *sic;
+
+ /* for the left & right operand :- look to see if the
+ left was assigned a true symbol in far space in that
+ case replace them */
+
+ if (IS_ITEMP (IC_LEFT (ic)) &&
+ OP_SYMBOL (IC_LEFT (ic))->liveTo <= ic->seq)
+ {
+ dic = findAssignToSym (IC_LEFT (ic), ic);
+
+ if (!dic)
+ goto right;
+
+ /* found it we need to remove it from the
+ block */
+ for (sic = dic; sic != ic; sic = sic->next)
+ bitVectUnSetBit (sic->rlive, IC_LEFT (ic)->key);
+
+ OP_SYMBOL(IC_LEFT (ic))=OP_SYMBOL(IC_RIGHT (dic));
+ IC_LEFT (ic)->key = OP_SYMBOL(IC_RIGHT (dic))->key;
+ remiCodeFromeBBlock (ebp, dic);
+ bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
+ hTabDeleteItem (&iCodehTab, dic->key, dic, DELETE_ITEM, NULL);
+ change++;
+ }
+
+ /* do the same for the right operand */
+ right:
+ if (!change &&
+ IS_ITEMP (IC_RIGHT (ic)) &&
+ OP_SYMBOL (IC_RIGHT (ic))->liveTo <= ic->seq)
+ {
+ iCode *dic = findAssignToSym (IC_RIGHT (ic), ic);
+ iCode *sic;
+
+ if (!dic)
+ return change;
+
+ /* if this is a subtraction & the result
+ is a true symbol in far space then don't pack */
+ if (ic->op == '-' && IS_TRUE_SYMOP (IC_RESULT (dic)))
+ {
+ sym_link *etype = getSpec (operandType (IC_RESULT (dic)));
+ if (IN_FARSPACE (SPEC_OCLS (etype)))
+ return change;
+ }
+ /* found it we need to remove it from the
+ block */
+ for (sic = dic; sic != ic; sic = sic->next)
+ bitVectUnSetBit (sic->rlive, IC_RIGHT (ic)->key);
+
+ IC_RIGHT (ic)->operand.symOperand =
+ IC_RIGHT (dic)->operand.symOperand;
+ IC_RIGHT (ic)->key = IC_RIGHT (dic)->operand.symOperand->key;
+
+ remiCodeFromeBBlock (ebp, dic);
+ bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
+ hTabDeleteItem (&iCodehTab, dic->key, dic, DELETE_ITEM, NULL);
+ change++;
+ }
+
+ return change;
+}
+
+#define IS_OP_RUONLY(x) (x && IS_SYMOP(x) && OP_SYMBOL(x)->ruonly)
+
+
+/*-----------------------------------------------------------------*/
+/* packRegsForOneuse : - will reduce some registers for single Use */
+/*-----------------------------------------------------------------*/
+static iCode *
+packRegsForOneuse (iCode * ic, operand * op, eBBlock * ebp)
+{
+ bitVect *uses;
+ iCode *dic, *sic;
+
+ /* if returning a literal then do nothing */
+ if (!IS_SYMOP (op))
+ return NULL;
+
+ if (ic->op != RETURN &&
+ ic->op != SEND &&
+ !POINTER_SET (ic) &&
+ !POINTER_GET (ic))
+ return NULL;
+
+ /* this routine will mark the a symbol as used in one
+ instruction use only && if the defintion is local
+ (ie. within the basic block) && has only one definition &&
+ that definiion is either a return value from a
+ function or does not contain any variables in
+ far space */
+ uses = bitVectCopy (OP_USES (op));
+ bitVectUnSetBit (uses, ic->key); /* take away this iCode */
+ if (!bitVectIsZero (uses)) /* has other uses */
+ return NULL;
+
+ /* if it has only one defintion */
+ if (bitVectnBitsOn (OP_DEFS (op)) > 1)
+ return NULL; /* has more than one definition */
+
+ /* get that definition */
+ if (!(dic =
+ hTabItemWithKey (iCodehTab,
+ bitVectFirstBit (OP_DEFS (op)))))
+ return NULL;
+
+ /* if that only usage is a cast */
+ if (dic->op == CAST) {
+ /* to a bigger type */
+ if (getSize(OP_SYM_TYPE(IC_RESULT(dic))) >
+ getSize(OP_SYM_TYPE(IC_RIGHT(dic)))) {
+ /* than we can not, since we cannot predict the usage of b & acc */
+ return NULL;
+ }
+ }
+
+ /* found the definition now check if it is local */
+ if (dic->seq < ebp->fSeq ||
+ dic->seq > ebp->lSeq)
+ return NULL; /* non-local */
+
+ /* now check if it is the return from
+ a function call */
+ if (dic->op == CALL || dic->op == PCALL)
+ {
+ if (ic->op != SEND && ic->op != RETURN &&
+ !POINTER_SET(ic) && !POINTER_GET(ic))
+ {
+ OP_SYMBOL (op)->ruonly = 1;
+ return dic;
+ }
+ dic = dic->next;
+ }
+
+
+ /* otherwise check that the definition does
+ not contain any symbols in far space */
+ if (isOperandInFarSpace (IC_LEFT (dic)) ||
+ isOperandInFarSpace (IC_RIGHT (dic)) ||
+ IS_OP_RUONLY (IC_LEFT (ic)) ||
+ IS_OP_RUONLY (IC_RIGHT (ic)))
+ {
+ return NULL;
+ }
+
+ /* if pointer set then make sure the pointer
+ is one byte */
+ if (POINTER_SET (dic) &&
+ !IS_DATA_PTR (aggrToPtr (operandType (IC_RESULT (dic)), FALSE)))
+ return NULL;
+
+ if (POINTER_GET (dic) &&
+ !IS_DATA_PTR (aggrToPtr (operandType (IC_LEFT (dic)), FALSE)))
+ return NULL;
+
+ sic = dic;
+
+ /* also make sure the intervenening instructions
+ don't have any thing in far space */
+ for (dic = dic->next; dic && dic != ic && sic != ic; dic = dic->next)
+ {
+
+ /* if there is an intervening function call then no */
+ if (dic->op == CALL || dic->op == PCALL)
+ return NULL;
+ /* if pointer set then make sure the pointer
+ is one byte */
+ if (POINTER_SET (dic) &&
+ !IS_DATA_PTR (aggrToPtr (operandType (IC_RESULT (dic)), FALSE)))
+ return NULL;
+
+ if (POINTER_GET (dic) &&
+ !IS_DATA_PTR (aggrToPtr (operandType (IC_LEFT (dic)), FALSE)))
+ return NULL;
+
+ /* if address of & the result is remat the okay */
+ if (dic->op == ADDRESS_OF &&
+ OP_SYMBOL (IC_RESULT (dic))->remat)
+ continue;
+
+ /* if operand has size of three or more & this
+ operation is a '*','/' or '%' then 'b' may
+ cause a problem */
+ if ((dic->op == '%' || dic->op == '/' || dic->op == '*') &&
+ getSize (operandType (op)) >= 3)
+ return NULL;
+
+ /* if left or right or result is in far space */
+ if (isOperandInFarSpace (IC_LEFT (dic)) ||
+ isOperandInFarSpace (IC_RIGHT (dic)) ||
+ isOperandInFarSpace (IC_RESULT (dic)) ||
+ IS_OP_RUONLY (IC_LEFT (dic)) ||
+ IS_OP_RUONLY (IC_RIGHT (dic)) ||
+ IS_OP_RUONLY (IC_RESULT (dic)))
+ {
+ return NULL;
+ }
+ /* if left or right or result is on stack */
+ if (isOperandOnStack(IC_LEFT(dic)) ||
+ isOperandOnStack(IC_RIGHT(dic)) ||
+ isOperandOnStack(IC_RESULT(dic))) {
+ return NULL;
+ }
+ }
+
+ OP_SYMBOL (op)->ruonly = 1;
+ return sic;
+
+}
+
+/*-----------------------------------------------------------------*/
+/* isBitwiseOptimizable - requirements of JEAN LOUIS VERN */
+/*-----------------------------------------------------------------*/
+static bool
+isBitwiseOptimizable (iCode * ic)
+{
+ sym_link *ltype = getSpec (operandType (IC_LEFT (ic)));
+ sym_link *rtype = getSpec (operandType (IC_RIGHT (ic)));
+
+ /* bitwise operations are considered optimizable
+ under the following conditions (Jean-Louis VERN)
+
+ x & lit
+ bit & bit
+ bit & x
+ bit ^ bit
+ bit ^ x
+ x ^ lit
+ x | lit
+ bit | bit
+ bit | x
+ */
+ if (IS_LITERAL(rtype) ||
+ (IS_BITVAR (ltype) && IN_BITSPACE (SPEC_OCLS (ltype))))
+ return TRUE;
+ else
+ return FALSE;
+}
+
+/*-----------------------------------------------------------------*/
+/* packForPush - hueristics to reduce iCode for pushing */
+/*-----------------------------------------------------------------*/
+static void
+packForPush (iCode * ic, eBBlock * ebp)
+{
+ iCode *dic, *lic;
+ bitVect *dbv;
+
+ if (ic->op != IPUSH || !IS_ITEMP (IC_LEFT (ic)))
+ return;
+
+ /* must have only definition & one usage */
+ if (bitVectnBitsOn (OP_DEFS (IC_LEFT (ic))) != 1 ||
+ bitVectnBitsOn (OP_USES (IC_LEFT (ic))) != 1)
+ return;
+
+ /* find the definition */
+ if (!(dic = hTabItemWithKey (iCodehTab,
+ bitVectFirstBit (OP_DEFS (IC_LEFT (ic))))))
+ return;
+
+ if (dic->op != '=' || POINTER_SET (dic))
+ return;
+
+ /* make sure the right side does not have any definitions
+ inbetween */
+ dbv = OP_DEFS(IC_RIGHT(dic));
+ for (lic = ic; lic && lic != dic ; lic = lic->prev) {
+ if (bitVectBitValue(dbv,lic->key))
+ return ;
+ }
+ /* make sure they have the same type */
+ {
+ sym_link *itype=operandType(IC_LEFT(ic));
+ sym_link *ditype=operandType(IC_RIGHT(dic));
+
+ if (SPEC_USIGN(itype)!=SPEC_USIGN(ditype) ||
+ SPEC_LONG(itype)!=SPEC_LONG(ditype))
+ return;
+ }
+ /* extend the live range of replaced operand if needed */
+ if (OP_SYMBOL(IC_RIGHT(dic))->liveTo < ic->seq) {
+ OP_SYMBOL(IC_RIGHT(dic))->liveTo = ic->seq;
+ }
+ /* we now know that it has one & only one def & use
+ and the that the definition is an assignment */
+ IC_LEFT (ic) = IC_RIGHT (dic);
+
+ remiCodeFromeBBlock (ebp, dic);
+ bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
+ hTabDeleteItem (&iCodehTab, dic->key, dic, DELETE_ITEM, NULL);
+}
+
+/*-----------------------------------------------------------------*/
+/* packRegisters - does some transformations to reduce register */
+/* pressure */
+/*-----------------------------------------------------------------*/
+static void packRegisters (eBBlock * ebp) {
+ iCode *ic;
+ int change = 0;
+
+ while (1) {
+ change = 0;
+
+ for (ic = ebp->sch; ic; ic = ic->next) {
+ if (ic->op == '=')
+ change += packRegsForAssign (ic, ebp);
+ }
+
+ if (!change)
+ break;
+ }
+ return; // that's it for now
+
+ for (ic = ebp->sch; ic; ic = ic->next)
+ {
+ /* if this is an itemp & result of an address of a true sym
+ then mark this as rematerialisable */
+ if (ic->op == ADDRESS_OF &&
+ IS_ITEMP (IC_RESULT (ic)) &&
+ IS_TRUE_SYMOP (IC_LEFT (ic)) &&
+ bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1 &&
+ !OP_SYMBOL (IC_LEFT (ic))->onStack)
+ {
+
+ OP_SYMBOL (IC_RESULT (ic))->remat = 1;
+ OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
+ OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
+
+ }
+
+ /* if straight assignment then carry remat flag if
+ this is the only definition */
+ if (ic->op == '=' &&
+ !POINTER_SET (ic) &&
+ IS_SYMOP (IC_RIGHT (ic)) &&
+ OP_SYMBOL (IC_RIGHT (ic))->remat &&
+ !IS_CAST_ICODE(OP_SYMBOL (IC_RIGHT (ic))->rematiCode) &&
+ bitVectnBitsOn (OP_SYMBOL (IC_RESULT (ic))->defs) <= 1)
+ {
+
+ OP_SYMBOL (IC_RESULT (ic))->remat =
+ OP_SYMBOL (IC_RIGHT (ic))->remat;
+ OP_SYMBOL (IC_RESULT (ic))->rematiCode =
+ OP_SYMBOL (IC_RIGHT (ic))->rematiCode;
+ }
+
+ /* if cast to a generic pointer & the pointer being
+ cast is remat, then we can remat this cast as well */
+ if (ic->op == CAST &&
+ IS_SYMOP(IC_RIGHT(ic)) &&
+ OP_SYMBOL(IC_RIGHT(ic))->remat ) {
+ sym_link *to_type = operandType(IC_LEFT(ic));
+ sym_link *from_type = operandType(IC_RIGHT(ic));
+ if (IS_GENPTR(to_type) && IS_PTR(from_type)) {
+ OP_SYMBOL (IC_RESULT (ic))->remat = 1;
+ OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
+ OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
+ }
+ }
+
+ /* if this is a +/- operation with a rematerizable
+ then mark this as rematerializable as well */
+ if ((ic->op == '+' || ic->op == '-') &&
+ (IS_SYMOP (IC_LEFT (ic)) &&
+ IS_ITEMP (IC_RESULT (ic)) &&
+ IS_OP_LITERAL (IC_RIGHT (ic))) &&
+ OP_SYMBOL (IC_LEFT (ic))->remat &&
+ (!IS_SYMOP (IC_RIGHT (ic)) || !IS_CAST_ICODE(OP_SYMBOL (IC_RIGHT (ic))->rematiCode)) &&
+ bitVectnBitsOn (OP_DEFS (IC_RESULT (ic))) == 1)
+ {
+ OP_SYMBOL (IC_RESULT (ic))->remat = 1;
+ OP_SYMBOL (IC_RESULT (ic))->rematiCode = ic;
+ OP_SYMBOL (IC_RESULT (ic))->usl.spillLoc = NULL;
+ }
+
+ /* mark the pointer usages */
+ if (POINTER_SET (ic))
+ OP_SYMBOL (IC_RESULT (ic))->uptr = 1;
+
+ if (POINTER_GET (ic))
+ OP_SYMBOL (IC_LEFT (ic))->uptr = 1;
+
+ /* if the condition of an if instruction
+ is defined in the previous instruction and
+ this is the only usage then
+ mark the itemp as a conditional */
+ if ((IS_CONDITIONAL (ic) ||
+ (IS_BITWISE_OP(ic) && isBitwiseOptimizable (ic))) &&
+ ic->next && ic->next->op == IFX &&
+ bitVectnBitsOn (OP_USES(IC_RESULT(ic)))==1 &&
+ isOperandEqual (IC_RESULT (ic), IC_COND (ic->next)) &&
+ OP_SYMBOL (IC_RESULT (ic))->liveTo <= ic->next->seq)
+ {
+ OP_SYMBOL (IC_RESULT (ic))->regType = REG_CND;
+ continue;
+ }
+
+ /* reduce for support function calls */
+ if (ic->supportRtn || ic->op == '+' || ic->op == '-')
+ packRegsForSupport (ic, ebp);
+
+ /* some cases the redundant moves can
+ can be eliminated for return statements */
+ if ((ic->op == RETURN || ic->op == SEND) &&
+ !isOperandInFarSpace (IC_LEFT (ic)) &&
+ options.model == MODEL_SMALL) {
+ if (0 && options.stackAuto) {
+ /* we should check here if acc will be clobbered for stack
+ offset calculations */
+ } else {
+ packRegsForOneuse (ic, IC_LEFT (ic), ebp);
+ }
+ }
+
+ /* if pointer set & left has a size more than
+ one and right is not in far space */
+ if (POINTER_SET (ic) &&
+ !isOperandInFarSpace (IC_RIGHT (ic)) &&
+ !OP_SYMBOL (IC_RESULT (ic))->remat &&
+ !IS_OP_RUONLY (IC_RIGHT (ic)) &&
+ getSize (aggrToPtr (operandType (IC_RESULT (ic)), FALSE)) > 1)
+
+ packRegsForOneuse (ic, IC_RESULT (ic), ebp);
+
+ /* if pointer get */
+ if (POINTER_GET (ic) &&
+ !isOperandInFarSpace (IC_RESULT (ic)) &&
+ !OP_SYMBOL (IC_LEFT (ic))->remat &&
+ !IS_OP_RUONLY (IC_RESULT (ic)) &&
+ getSize (aggrToPtr (operandType (IC_LEFT (ic)), FALSE)) > 1)
+
+ packRegsForOneuse (ic, IC_LEFT (ic), ebp);
+
+
+ /* if this is cast for intergral promotion then
+ check if only use of the definition of the
+ operand being casted/ if yes then replace
+ the result of that arithmetic operation with
+ this result and get rid of the cast */
+ if (ic->op == CAST)
+ {
+ sym_link *fromType = operandType (IC_RIGHT (ic));
+ sym_link *toType = operandType (IC_LEFT (ic));
+
+ if (IS_INTEGRAL (fromType) && IS_INTEGRAL (toType) &&
+ getSize (fromType) != getSize (toType) &&
+ SPEC_USIGN (fromType) == SPEC_USIGN (toType))
+ {
+
+ iCode *dic = packRegsForOneuse (ic, IC_RIGHT (ic), ebp);
+ if (dic)
+ {
+ if (IS_ARITHMETIC_OP (dic))
+ {
+ bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
+ IC_RESULT (dic) = IC_RESULT (ic);
+ remiCodeFromeBBlock (ebp, ic);
+ bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
+ hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
+ OP_DEFS (IC_RESULT (dic)) = bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
+ ic = ic->prev;
+ }
+ else
+ OP_SYMBOL (IC_RIGHT (ic))->ruonly = 0;
+ }
+ }
+ else
+ {
+
+ /* if the type from and type to are the same
+ then if this is the only use then packit */
+ if (compareType (operandType (IC_RIGHT (ic)),
+ operandType (IC_LEFT (ic))) == 1)
+ {
+ iCode *dic = packRegsForOneuse (ic, IC_RIGHT (ic), ebp);
+ if (dic)
+ {
+ bitVectUnSetBit(OP_SYMBOL(IC_RESULT(dic))->defs,dic->key);
+ IC_RESULT (dic) = IC_RESULT (ic);
+ remiCodeFromeBBlock (ebp, ic);
+ bitVectUnSetBit(OP_SYMBOL(IC_RESULT(ic))->defs,ic->key);
+ hTabDeleteItem (&iCodehTab, ic->key, ic, DELETE_ITEM, NULL);
+ OP_DEFS (IC_RESULT (dic)) = bitVectSetBit (OP_DEFS (IC_RESULT (dic)), dic->key);
+ ic = ic->prev;
+ }
+ }
+ }
+ }
+
+ /* pack for PUSH
+ iTempNN := (some variable in farspace) V1
+ push iTempNN ;
+ -------------
+ push V1
+ */
+ if (ic->op == IPUSH)
+ {
+ packForPush (ic, ebp);
+ }
+ }
+}
+
+/*-----------------------------------------------------------------*/
+/* assignRegisters - assigns registers to each live range as need */
+/*-----------------------------------------------------------------*/
+void
+xa51_assignRegisters (eBBlock ** ebbs, int count)
+{
+ iCode *ic;
+ int i;
+
+ setToNull ((void *) &_G.funcrUsed);
+ setToNull ((void *) &_G.totRegAssigned);
+ _G.stackExtend = _G.dataExtend = 0;
+
+ /* change assignments this will remove some
+ live ranges reducing some register pressure */
+ for (i = 0; i < count; i++)
+ packRegisters (ebbs[i]);
+
+ if (options.dump_pack)
+ dumpEbbsToFileExt (DUMP_PACK, ebbs, count);
+
+ /* first determine for each live range the number of
+ registers & the type of registers required for each */
+ regTypeNum (*ebbs);
+
+ /* and serially allocate registers */
+ serialRegAssign (ebbs, count);
+
+ freeAllRegs ();
+
+ /* if stack was extended then tell the user */
+ if (_G.stackExtend)
+ {
+/* werror(W_TOOMANY_SPILS,"stack", */
+/* _G.stackExtend,currFunc->name,""); */
+ _G.stackExtend = 0;
+ }
+
+ if (_G.dataExtend)
+ {
+/* werror(W_TOOMANY_SPILS,"data space", */
+/* _G.dataExtend,currFunc->name,""); */
+ _G.dataExtend = 0;
+ }
+
+ /* after that create the register mask
+ for each of the instruction */
+ createRegMask (ebbs, count);
+
+ /* redo that offsets for stacked automatic variables */
+ redoStackOffsets ();
+
+ if (options.dump_rassgn)
+ {
+ dumpEbbsToFileExt (DUMP_RASSGN, ebbs, count);
+ dumpLiveRanges (DUMP_LRANGE, liveRanges);
+ }
+
+ /* do the overlaysegment stuff SDCCmem.c */
+ doOverlays (ebbs, count);
+
+ /* now get back the chain */
+ ic = iCodeLabelOptimize (iCodeFromeBBlock (ebbs, count));
+
+ genXA51Code (ic);
+
+ /* free up any _G.stackSpil locations allocated */
+ applyToSet (_G.stackSpil, deallocStackSpil);
+ _G.slocNum = 0;
+ setToNull ((void **) &_G.stackSpil);
+ setToNull ((void **) &_G.spiltSet);
+ /* mark all registers as free */
+ freeAllRegs ();
+
+ return;
+}