extern void pCodeInsertAfter(pCode *pc1, pCode *pc2);
extern void dbg_dumpregusage(void);
+extern pCode * findPrevInstruction(pCode *pci);
void unlinkpCode(pCode *pc);
int total_registers_saved=0;
for (reg = setFirstItem(fregs) ; reg ;
reg = setNextItem(fregs)) {
-
- fprintf (stderr, "%s addr=0x%03x rIdx=0x%03x",
- reg->name,
- reg->address,
- reg->rIdx);
-
- pcfl = setFirstItem(reg->reglives.usedpFlows);
- if(pcfl)
- fprintf(stderr, "\n used in seq");
-
- while(pcfl) {
- fprintf(stderr," 0x%03x",pcfl->seq);
- pcfl = setNextItem(reg->reglives.usedpFlows);
- }
- pcfl = setFirstItem(reg->reglives.assignedpFlows);
- if(pcfl)
- fprintf(stderr, "\n assigned in seq");
+ if(elementsInSet(reg->reglives.usedpCodes)) {
+
+ fprintf (stderr, "%s addr=0x%03x rIdx=0x%03x",
+ reg->name,
+ reg->address,
+ reg->rIdx);
- while(pcfl) {
- fprintf(stderr," 0x%03x",pcfl->seq);
- pcfl = setNextItem(reg->reglives.assignedpFlows);
- }
+ pcfl = setFirstItem(reg->reglives.usedpFlows);
+ if(pcfl)
+ fprintf(stderr, "\n used in seq");
- pc = setFirstItem(reg->reglives.usedpCodes);
- if(pc)
- fprintf(stderr, "\n used in instructions ");
+ while(pcfl) {
+ fprintf(stderr," 0x%03x",pcfl->seq);
+ pcfl = setNextItem(reg->reglives.usedpFlows);
+ }
- while(pc) {
- pcfl = PCODE(PCI(pc)->pcflow);
+ pcfl = setFirstItem(reg->reglives.assignedpFlows);
if(pcfl)
- fprintf(stderr," 0x%03x:",pcfl->seq);
- fprintf(stderr,"0x%03x",pc->seq);
+ fprintf(stderr, "\n assigned in seq");
- pc = setNextItem(reg->reglives.usedpCodes);
- }
+ while(pcfl) {
+ fprintf(stderr," 0x%03x",pcfl->seq);
+ pcfl = setNextItem(reg->reglives.assignedpFlows);
+ }
+
+ pc = setFirstItem(reg->reglives.usedpCodes);
+ if(pc)
+ fprintf(stderr, "\n used in instructions ");
- fprintf(stderr, "\n");
+ while(pc) {
+ pcfl = PCODE(PCI(pc)->pcflow);
+ if(pcfl)
+ fprintf(stderr," 0x%03x:",pcfl->seq);
+ fprintf(stderr,"0x%03x",pc->seq);
+
+ pc = setNextItem(reg->reglives.usedpCodes);
+ }
+ fprintf(stderr, "\n");
+ }
}
}
addSetIfnotP(& (PCFL(pcfl)->registers), reg);
- if(PCC_REGISTER & PCI(pc)->inCond)
+ if((PCC_REGISTER | PCC_LITERAL) & PCI(pc)->inCond)
addSetIfnotP(& (reg->reglives.usedpFlows), pcfl);
if(PCC_REGISTER & PCI(pc)->outCond)
}
- //dbg_dumpregusage();
+// dbg_dumpregusage();
}
*-----------------------------------------------------------------*/
static void Remove2pcodes(pCode *pcflow, pCode *pc1, pCode *pc2, regs *reg)
{
+ if(!reg)
+ return;
+
+ if(pc1) {
+ deleteSetItem (&(reg->reglives.usedpCodes),pc1);
+ pc1->destruct(pc1);
+ }
- deleteSetItem (&(reg->reglives.usedpCodes),pc1);
- deleteSetItem (&(reg->reglives.usedpCodes),pc2);
- deleteSetItem (&(PCFL(pcflow)->registers), reg);
+ if(pc2) {
+ deleteSetItem (&(reg->reglives.usedpCodes),pc2);
+ pc2->destruct(pc2);
- pc1->destruct(pc1);
- pc2->destruct(pc2);
+ deleteSetItem (&(PCFL(pcflow)->registers), reg);
+
+ reg->isFree = 1;
+ reg->wasUsed = 0;
+
+ }
- reg->isFree = 1;
- reg->wasUsed = 0;
pCodeRegMapLiveRangesInFlow(PCFL(pcflow));
}
while(fregs) {
+ pCode *pcfl_used, *pcfl_assigned;
/* Step through the set by directly accessing the 'next' pointer.
* We could also step through by using the set API, but the
reg = fregs->item;
fregs = fregs->next;
- used = elementsInSet(reg->reglives.usedpCodes);
+ pcfl_used = setFirstItem(reg->reglives.usedpFlows);
+ pcfl_assigned = setFirstItem(reg->reglives.assignedpFlows);
+
+ used = elementsInSet(reg->reglives.usedpCodes);
if(used == 2) {
- pCode *pcfl_used, *pcfl_assigned;
+ /*
+ * In this section, all registers that are used in only in two
+ * instructions are examined. If possible, they're optimized out.
+ */
+
pCode *pc1, *pc2;
- pCode *t;
+ pCode *pct1, *pct2; /* two temporaries */
+ regs *reg1, *reg2;
- /* This register has only been used twice. Chances are we can
- get rid of it */
/*
fprintf (stderr, "OptimizeRegUsage: %s addr=0x%03x rIdx=0x%03x used=%d\n",
reg->name,
reg->address,
reg->rIdx, used);
*/
- pcfl_used = setFirstItem(reg->reglives.usedpFlows);
- pcfl_assigned = setFirstItem(reg->reglives.assignedpFlows);
-
pc1 = setFirstItem(reg->reglives.usedpCodes);
pc2 = setNextItem(reg->reglives.usedpCodes);
expected case - the register has been assigned a value and is
subsequently used
*/
+
//fprintf(stderr," used only twice\n");
if(pcfl_used->seq == pcfl_assigned->seq) {
//fprintf(stderr, " and used in same flow\n");
if(pc2->seq < pc1->seq) {
- t = pc2;
+ pct1 = pc2;
pc2 = pc1;
- pc1 = t;
+ pc1 = pct1;
}
//pc1->print(stderr,pc1);
//pc2->print(stderr,pc2);
- /* ADHOC pattern checking */
+ /* ADHOC pattern checking
+ * Now look for specific sequences that are easy to optimize.
+ * Many of these sequences are characteristic of the compiler
+ * (i.e. it'd probably be a waste of time to apply these adhoc
+ * checks to hand written assembly.)
+ *
+ */
if((PCI(pc1)->op == POC_CLRF) && (PCI(pc2)->op == POC_MOVFW) ){
+
+ /*
+ clrf reg
+ stuff...
+ movf reg,w
+
+ can be replaced with
+
+ stuff...
+ movlw 0
+ */
+
pCode *newpc;
//fprintf(stderr, " CLRF/MOVFW. instruction after MOVFW is:\n");
- t = findNextInstruction(pc2->next);
+ pct1 = findNextInstruction(pc2->next);
//t->print(stderr,t);
- if(PCI(t)->op == POC_MOVWF) {
- newpc = newpCode(POC_CLRF, PCI(t)->pcop);
+ if(PCI(pct1)->op == POC_MOVWF) {
+ newpc = newpCode(POC_CLRF, PCI(pct1)->pcop);
+ pct1->destruct(pct1);
} else {
newpc = newpCode(POC_MOVLW, newpCodeOpLit(0));
}
+ pCodeInsertAfter(pc2, newpc);
PCI(newpc)->pcflow = PCFL(pcfl_used);
- newpc->seq = t->seq;
-
- pCodeInsertAfter(t, newpc);
+ newpc->seq = pc2->seq;
- t->destruct(t);
Remove2pcodes(pcfl_used, pc1, pc2, reg);
total_registers_saved++; // debugging stats.
Remove2pcodes(pcfl_used, pc1, pc2, reg);
total_registers_saved++; // debugging stats.
- } else if((PCI(pc1)->op == POC_MOVWF) && (PCI(pc2)->op == POC_MOVFW) ){
- //fprintf(stderr, " MOVWF/MOVFW. instruction after MOVFW is:\n");
- t = findNextInstruction(pc2->next);
- // t->print(stderr,t);
-
- if(PCI(t)->op == POC_MOVWF) {
- regs *nextreg = getRegFromInstruction(t);
- if(nextreg && !regUsedinRange(pc1,pc2,nextreg)) {
- t->seq = pc1->seq;
- unlinkpCode(t);
- pCodeInsertAfter(pc1,t);
+ } else if(PCI(pc1)->op == POC_MOVWF) {
+
+ pct2 = findNextInstruction(pc2->next);
+
+ if(PCI(pc2)->op == POC_MOVFW) {
+ //fprintf(stderr, " MOVWF/MOVFW. instruction after MOVFW is:\n");
+ // t->print(stderr,t);
+
+ if(PCI(pct2)->op == POC_MOVWF) {
+ reg2 = getRegFromInstruction(pct2);
+ if(reg2 && !regUsedinRange(pc1,pc2,reg2)) {
+ pct2->seq = pc1->seq;
+ unlinkpCode(pct2);
+ pCodeInsertAfter(pc1,pct2);
+ Remove2pcodes(pcfl_used, pc1, pc2, reg);
+ total_registers_saved++; // debugging stats.
+ continue;
+ }
+ }
+ }
+
+ pct1 = findPrevInstruction(pc1->prev);
+ if(pct1 &&
+ (PCI(pct1)->pcflow == PCI(pc1)->pcflow) &&
+ (PCI(pct1)->op == POC_MOVFW)) {
+
+ reg1 = getRegFromInstruction(pct1);
+ if(reg1 && !regUsedinRange(pc1,pc2,reg1)) {
+ /*
+ movf reg1,w
+ movwf reg
+
+ stuff...
+ opcode reg,w
+ */
+ pct2 = newpCode(PCI(pc2)->op, PCI(pct1)->pcop);
+ pCodeInsertAfter(pc2, pct2);
+ PCI(pct2)->pcflow = PCFL(pcfl_used);
+ pct2->seq = pc2->seq;
+
Remove2pcodes(pcfl_used, pc1, pc2, reg);
+ Remove2pcodes(pcfl_used, pct1, NULL, reg1);
total_registers_saved++; // debugging stats.
+
}
}
+
+
}
} else {
/*
register has been used twice without ever being assigned */
fprintf(stderr,"WARNING %s: reg %s used without being assigned\n",__FUNCTION__,reg->name);
+
} else {
- fprintf(stderr,"WARNING %s: reg %s assigned without being used\n",__FUNCTION__,reg->name);
+ //fprintf(stderr,"WARNING %s: reg %s assigned without being used\n",__FUNCTION__,reg->name);
+ Remove2pcodes(pcfl_assigned, pc1, pc2, reg);
+ total_registers_saved++; // debugging stats.
}
} else {
- //if(used) fprintf (stderr, " over used OptimizeRegUsage: %s used=%d\n", reg->name, used);
-
- }
- }
+ if(used && !pcfl_used && pcfl_assigned) {
+ pCode *pc;
-#if 0
- pcfl = setFirstItem(reg->reglives.usedpFlows);
- if(pcfl)
- fprintf(stderr, "\n used in seq");
+ //fprintf(stderr,"WARNING %s: reg %s assigned without being used\n",__FUNCTION__,reg->name);
- while(pcfl) {
- fprintf(stderr," 0x%03x",pcfl->seq);
- pcfl = setNextItem(reg->reglives.usedpFlows);
- }
+ pc = setFirstItem(reg->reglives.usedpCodes);
+ while(pc) {
+ pcfl_assigned = PCI(pc)->pcflow;
+ deleteSetItem (&(PCFL(pcfl_assigned)->registers), reg);
+ deleteSetItem (&(reg->reglives.usedpCodes),pc);
+ pc->destruct(pc);
- pcfl = setFirstItem(reg->reglives.assignedpFlows);
- if(pcfl)
- fprintf(stderr, "\n assigned in seq");
+ pc = setNextItem(reg->reglives.usedpCodes);
+ }
- while(pcfl) {
- fprintf(stderr," 0x%03x",pcfl->seq);
- pcfl = setNextItem(reg->reglives.assignedpFlows);
- }
- pc = setFirstItem(reg->reglives.usedpCodes);
- if(pc)
- fprintf(stderr, "\n used in instructions ");
+ reg->isFree = 1;
+ reg->wasUsed = 0;
- while(pc) {
- pcfl = PCODE(PCI(pc)->pcflow);
- if(pcfl)
- fprintf(stderr," 0x%03x:",pcfl->seq);
- fprintf(stderr,"0x%03x",pc->seq);
+ total_registers_saved++; // debugging stats.
+ }
- pc = setNextItem(reg->reglives.usedpCodes);
}
- fprintf(stderr, "\n");
-
}
-#endif
+
}
/*-----------------------------------------------------------------*
* void pCodeRegOptimeRegUsage(pBlock *pb)
/* Identify registers used in one flow sequence */
OptimizeRegUsage(dynAllocRegs);
+ OptimizeRegUsage(dynStackRegs);
+ OptimizeRegUsage(dynDirectRegs);
if(total_registers_saved != saved)
fprintf(stderr, " *** Saved %d registers, total saved %d ***\n", total_registers_saved-saved,total_registers_saved);
} while( passes-- && (total_registers_saved != saved));
+/*
+ fprintf(stderr,"dynamically allocated regs:\n");
+ dbg_regusage(dynAllocRegs);
+ fprintf(stderr,"stack regs:\n");
+ dbg_regusage(dynStackRegs);
+ fprintf(stderr,"direct regs:\n");
+ dbg_regusage(dynDirectRegs);
+*/
+
}
projects / fw / sdcc / blobdiff