#define BYTEofLONG(l,b) ( (l>> (b<<3)) & 0xff)
-void DEBUGpic14_AopType(int line_no, operand *left, operand *right, operand *result);
+extern void DEBUGpic14_AopType(int line_no, operand *left, operand *right, operand *result);
const char *AopType(short type)
{
freeAsmop(IC_RESULT(ic),NULL,ic,TRUE);
}
-/*-----------------------------------------------------------------*/
-/* genMinusDec :- does subtraction with decrement if possible */
-/*-----------------------------------------------------------------*/
-bool genMinusDec (iCode *ic)
-{
- unsigned int icount ;
- unsigned int size = pic14_getDataSize(IC_RESULT(ic));
- FENTRY;
-
- DEBUGpic14_emitcode ("; ***","%s %d",__FUNCTION__,__LINE__);
- /* will try to generate an increment */
- /* if the right side is not a literal
- we cannot */
- if ((AOP_TYPE(IC_RIGHT(ic)) != AOP_LIT) ||
- (AOP_TYPE(IC_LEFT(ic)) == AOP_CRY) ||
- (AOP_TYPE(IC_RESULT(ic)) == AOP_CRY) )
- return FALSE ;
-
- DEBUGpic14_emitcode ("; lit val","%d",(unsigned int) ulFromVal (AOP(IC_RIGHT(ic))->aopu.aop_lit));
-
- /* if the literal value of the right hand side
- is greater than 4 then it is not worth it */
- if ((icount = (unsigned int) ulFromVal (AOP(IC_RIGHT(ic))->aopu.aop_lit)) > 2)
- return FALSE ;
-
- /* if decrement 16 bits in register */
- if (pic14_sameRegs(AOP(IC_LEFT(ic)), AOP(IC_RESULT(ic))) &&
- (size > 1) &&
- (icount == 1)) {
-
- if(size == 2) {
- emitpcode(POC_DECF, popGet(AOP(IC_RESULT(ic)),LSB));
- emitpcode(POC_INCFSZW, popGet(AOP(IC_RESULT(ic)),LSB));
- emitpcode(POC_INCF, popGet(AOP(IC_RESULT(ic)),MSB16));
- emitpcode(POC_DECF, popGet(AOP(IC_RESULT(ic)),MSB16));
-
- pic14_emitcode("decf","%s,f",aopGet(AOP(IC_RESULT(ic)),LSB,FALSE,FALSE));
- pic14_emitcode("incfsz","%s,w",aopGet(AOP(IC_RESULT(ic)),LSB,FALSE,FALSE));
- pic14_emitcode(" decf","%s,f",aopGet(AOP(IC_RESULT(ic)),MSB16,FALSE,FALSE));
- } else {
- /* size is 3 or 4 */
- emitpcode(POC_MOVLW, popGetLit(0xff));
- emitpcode(POC_ADDWF, popGet(AOP(IC_RESULT(ic)),LSB));
- emitSKPNC;
- emitpcode(POC_ADDWF, popGet(AOP(IC_RESULT(ic)),MSB16));
- emitSKPNC;
- emitpcode(POC_ADDWF, popGet(AOP(IC_RESULT(ic)),MSB24));
-
- pic14_emitcode("movlw","0xff");
- pic14_emitcode("addwf","%s,f",aopGet(AOP(IC_RESULT(ic)),LSB,FALSE,FALSE));
-
- emitSKPNC;
- pic14_emitcode("addwf","%s,f",aopGet(AOP(IC_RESULT(ic)),MSB16,FALSE,FALSE));
- emitSKPNC;
- pic14_emitcode("addwf","%s,f",aopGet(AOP(IC_RESULT(ic)),MSB24,FALSE,FALSE));
-
- if(size > 3) {
- emitSKPNC;
- emitpcode(POC_ADDWF, popGet(AOP(IC_RESULT(ic)),MSB32));
-
- pic14_emitcode("skpnc","");
- emitSKPNC;
- pic14_emitcode("addwf","%s,f",aopGet(AOP(IC_RESULT(ic)),MSB32,FALSE,FALSE));
- }
-
- }
-
- return TRUE;
-
- }
-
- /* if the sizes are greater than 1 then we cannot */
- if (AOP_SIZE(IC_RESULT(ic)) > 1 ||
- AOP_SIZE(IC_LEFT(ic)) > 1 )
- return FALSE ;
-
- /* we can if the aops of the left & result match or
- if they are in registers and the registers are the
- same */
- if (pic14_sameRegs(AOP(IC_LEFT(ic)), AOP(IC_RESULT(ic)))) {
-
- while (icount--)
- emitpcode(POC_DECF, popGet(AOP(IC_RESULT(ic)),0));
-
- //pic14_emitcode ("decf","%s,f",aopGet(AOP(IC_RESULT(ic)),0,FALSE,FALSE));
-
- return TRUE ;
- }
-
- DEBUGpic14_emitcode ("; returning"," result=%s, left=%s",
- aopGet(AOP(IC_RESULT(ic)),0,FALSE,FALSE),
- aopGet(AOP(IC_LEFT(ic)),0,FALSE,FALSE));
- if(size==1) {
-
- pic14_emitcode("decf","%s,w",aopGet(AOP(IC_LEFT(ic)),0,FALSE,FALSE));
- pic14_emitcode("movwf","%s",aopGet(AOP(IC_RESULT(ic)),0,FALSE,FALSE));
-
- emitpcode(POC_DECFW, popGet(AOP(IC_LEFT(ic)),0));
- emitpcode(POC_MOVWF, popGet(AOP(IC_RESULT(ic)),0));
-
- return TRUE;
- }
-
- return FALSE ;
-}
-
/*-----------------------------------------------------------------*/
/* addSign - propogate sign bit to higher bytes */
/*-----------------------------------------------------------------*/
{
int size, offset = 0, same=0;
unsigned long lit = 0L;
-
+ int isLit;
+ symbol *lbl_comm, *lbl_next;
+ asmop *left, *right, *result;
+
FENTRY;
DEBUGpic14_emitcode ("; ***","%s %d",__FUNCTION__,__LINE__);
aopOp (IC_LEFT(ic),ic,FALSE);
AopType(AOP_TYPE(IC_LEFT(ic))),
AopType(AOP_TYPE(IC_RIGHT(ic))));
- /* if I can do an decrement instead
- of subtract then GOOD for ME */
- // if (genMinusDec (ic) == TRUE)
- // goto release;
+ left = AOP(IC_LEFT(ic));
+ right = AOP(IC_RIGHT(ic));
+ result = AOP(IC_RESULT(ic));
- size = pic14_getDataSize(IC_RESULT(ic));
- same = pic14_sameRegs(AOP(IC_RIGHT(ic)), AOP(IC_RESULT(ic)));
-
- if(AOP(IC_RIGHT(ic))->type == AOP_LIT) {
+ size = pic14_getDataSize(IC_RESULT(ic));
+ same = pic14_sameRegs(right, result);
+
+ if((AOP_TYPE(IC_LEFT(ic)) != AOP_LIT)
+ && (pic14_getDataSize(IC_LEFT(ic)) < size))
+ {
+ fprintf(stderr, "%s:%d(%s):WARNING: left operand too short for result\n",
+ ic->filename, ic->lineno, __FUNCTION__);
+ } // if
+ if((AOP_TYPE(IC_RIGHT(ic)) != AOP_LIT)
+ && (pic14_getDataSize(IC_RIGHT(ic)) < size))
+ {
+ fprintf(stderr, "%s:%d(%s):WARNING: right operand too short for result\n",
+ ic->filename, ic->lineno, __FUNCTION__ );
+ } // if
+
+ if(AOP_TYPE(IC_RIGHT(ic)) == AOP_LIT) {
/* Add a literal to something else */
- lit = ulFromVal (AOP(IC_RIGHT(ic))->aopu.aop_lit);
- lit = - (long)lit;
-
- genAddLit ( ic, lit);
+ lit = ulFromVal(right->aopu.aop_lit);
+ lit = -(long)lit;
-#if 0
- /* add the first byte: */
- pic14_emitcode("movlw","0x%x", lit & 0xff);
- pic14_emitcode("addwf","%s,f", aopGet(AOP(IC_LEFT(ic)),0,FALSE,FALSE));
- emitpcode(POC_MOVLW, popGetLit(lit & 0xff));
- emitpcode(POC_ADDWF, popGet(AOP(IC_LEFT(ic)),0));
+ genAddLit(ic, lit);
-
- offset = 1;
- size--;
-
- while(size-- > 0) {
-
- lit >>= 8;
-
- if(lit & 0xff) {
-
- if((lit & 0xff) == 0xff) {
- emitpcode(POC_MOVLW, popGetLit(0xff));
- emitSKPC;
- emitpcode(POC_ADDWF, popGet(AOP(IC_LEFT(ic)),offset));
- } else {
- emitpcode(POC_MOVLW, popGetLit(lit & 0xff));
- emitSKPNC;
- emitpcode(POC_MOVLW, popGetLit((lit+1) & 0xff));
- emitpcode(POC_ADDWF, popGet(AOP(IC_LEFT(ic)),offset));
- }
-
- } else {
- /* do the rlf known zero trick here */
- emitpcode(POC_MOVLW, popGetLit(1));
- emitSKPNC;
- emitpcode(POC_ADDWF, popGet(AOP(IC_LEFT(ic)),offset));
- }
- offset++;
- }
-#endif
} else if(AOP_TYPE(IC_RIGHT(ic)) == AOP_CRY) {
// bit subtraction
- pic14_emitcode(";bitsub","right is bit: %s",aopGet(AOP(IC_RIGHT(ic)),0,FALSE,FALSE));
- pic14_emitcode(";bitsub","left is bit: %s",aopGet(AOP(IC_LEFT(ic)),0,FALSE,FALSE));
- pic14_emitcode(";bitsub","result is bit: %s",aopGet(AOP(IC_RESULT(ic)),0,FALSE,FALSE));
+ pic14_emitcode(";bitsub","right is bit: %s",aopGet(right,0,FALSE,FALSE));
+ pic14_emitcode(";bitsub","left is bit: %s",aopGet(left,0,FALSE,FALSE));
+ pic14_emitcode(";bitsub","result is bit: %s",aopGet(result,0,FALSE,FALSE));
/* here we are subtracting a bit from a char or int */
if(size == 1) {
- if (pic14_sameRegs(AOP(IC_LEFT(ic)), AOP(IC_RESULT(ic))) ) {
+ if(pic14_sameRegs(left, result)) {
- emitpcode(POC_BTFSC , popGet(AOP(IC_RIGHT(ic)),0));
- emitpcode(POC_DECF , popGet(AOP(IC_RESULT(ic)),0));
+ emitpcode(POC_BTFSC, popGet(right, 0));
+ emitpcode(POC_DECF , popGet(result, 0));
- pic14_emitcode("btfsc","(%s >> 3), (%s & 7)",
- AOP(IC_RIGHT(ic))->aopu.aop_dir,
- AOP(IC_RIGHT(ic))->aopu.aop_dir);
- pic14_emitcode(" incf","%s,f", aopGet(AOP(IC_RESULT(ic)),0,FALSE,FALSE));
} else {
- if( (AOP_TYPE(IC_LEFT(ic)) == AOP_IMMD) ||
+ if( (AOP_TYPE(IC_LEFT(ic)) == AOP_IMMD) ||
(AOP_TYPE(IC_LEFT(ic)) == AOP_LIT) ) {
+ /*
+ * result = literal - bit
+ *
+ * XXX: probably fails for AOP_IMMDs!
+ */
- lit = ulFromVal (AOP(IC_LEFT(ic))->aopu.aop_lit);
+ lit = ulFromVal (left->aopu.aop_lit);
if(AOP_TYPE(IC_RESULT(ic)) == AOP_CRY) {
- if (pic14_sameRegs(AOP(IC_RIGHT(ic)), AOP(IC_RESULT(ic))) ) {
+ if(pic14_sameRegs(right, result)) {
if(lit & 1) {
- emitpcode(POC_MOVLW , popGet(AOP(IC_RIGHT(ic)),0));
- emitpcode(POC_XORWF , popGet(AOP(IC_RIGHT(ic)),0));
+ emitpcode(POC_MOVLW, popGet(right, 0));
+ emitpcode(POC_XORWF, popGet(result, 0));
}
- }else{
- emitpcode(POC_BCF , popGet(AOP(IC_RESULT(ic)),0));
+ } else {
+ emitpcode(POC_BCF, popGet(result, 0));
if(lit & 1)
- emitpcode(POC_BTFSS , popGet(AOP(IC_RIGHT(ic)),0));
+ emitpcode(POC_BTFSS, popGet(right, 0));
else
- emitpcode(POC_BTFSC , popGet(AOP(IC_RIGHT(ic)),0));
- emitpcode(POC_BSF , popGet(AOP(IC_RESULT(ic)),0));
+ emitpcode(POC_BTFSC, popGet(right, 0));
+ emitpcode(POC_BSF, popGet(result, 0));
}
goto release;
} else {
- emitpcode(POC_MOVLW , popGetLit(lit & 0xff));
- emitpcode(POC_BTFSC , popGet(AOP(IC_RIGHT(ic)),0));
- emitpcode(POC_MOVLW , popGetLit((lit-1) & 0xff));
- emitpcode(POC_MOVWF , popGet(AOP(IC_RESULT(ic)),0));
-
+ emitpcode(POC_MOVLW, popGetLit(lit & 0xff));
+ emitpcode(POC_BTFSC, popGet(right, 0));
+ emitpcode(POC_MOVLW, popGetLit((lit-1) & 0xff));
+ emitpcode(POC_MOVWF, popGet(result, 0));
}
} else {
- emitpcode(POC_MOVFW , popGet(AOP(IC_LEFT(ic)),0));
- emitpcode(POC_BTFSC , popGet(AOP(IC_RIGHT(ic)),0));
- emitpcode(POC_DECFW , popGet(AOP(IC_LEFT(ic)),0));
- }
-
- emitpcode(POC_MOVWF , popGet(AOP(IC_RESULT(ic)),0));
- }
-
- }
- } else if(// (AOP_TYPE(IC_LEFT(ic)) == AOP_IMMD) ||
- (AOP(IC_LEFT(ic))->type == AOP_LIT)) {
-
- lit = ulFromVal (AOP(IC_LEFT(ic))->aopu.aop_lit);
- DEBUGpic14_emitcode ("; left is lit","line %d result %s, left %s, right %s",__LINE__,
- AopType(AOP_TYPE(IC_RESULT(ic))),
- AopType(AOP_TYPE(IC_LEFT(ic))),
- AopType(AOP_TYPE(IC_RIGHT(ic))));
-
-
- if( (size == 1) && ((lit & 0xff) == 0) ) {
- /* res = 0 - right */
- if (pic14_sameRegs(AOP(IC_RIGHT(ic)), AOP(IC_RESULT(ic))) ) {
- emitpcode(POC_COMF, popGet(AOP(IC_RIGHT(ic)),0));
- emitpcode(POC_INCF, popGet(AOP(IC_RIGHT(ic)),0));
- } else {
- emitpcode(POC_COMFW, popGet(AOP(IC_RIGHT(ic)),0));
- emitpcode(POC_MOVWF, popGet(AOP(IC_RESULT(ic)),0));
- emitpcode(POC_INCF, popGet(AOP(IC_RESULT(ic)),0));
- }
- goto release;
- }
-
- emitpcode(POC_MOVFW, popGet(AOP(IC_RIGHT(ic)),0));
- emitpcode(POC_SUBLW, popGetLit(lit & 0xff));
- emitpcode(POC_MOVWF,popGet(AOP(IC_RESULT(ic)),0));
-
-
- offset = 1;
- while(--size) {
- lit >>= 8;
-
- if(size == 1) {
- /* This is the last byte in a multibyte subtraction
- * There are a couple of tricks we can do by not worrying about
- * propogating the carry */
- if(lit == 0xff) {
- /* 0xff - x == ~x */
- if(same) {
- emitpcode(POC_COMF, popGet(AOP(IC_RESULT(ic)),offset));
- emitSKPC;
- emitpcode(POC_DECF, popGet(AOP(IC_RESULT(ic)),offset));
- } else {
- emitpcode(POC_COMFW, popGet(AOP(IC_RIGHT(ic)),offset));
- emitpcode(POC_MOVWF, popGet(AOP(IC_RESULT(ic)),offset));
- emitSKPC;
- emitpcode(POC_DECF, popGet(AOP(IC_RESULT(ic)),offset));
- }
- } else {
- emitpcode(POC_MOVFW, popGet(AOP(IC_RIGHT(ic)),offset));
- emitSKPC;
- emitpcode(POC_INCFW, popGet(AOP(IC_RIGHT(ic)),offset));
- emitpcode(POC_SUBLW, popGetLit(lit & 0xff));
- emitpcode(POC_MOVWF, popGet(AOP(IC_RESULT(ic)),offset));
+ // result = register - bit
+ // XXX: Fails for lit-like left operands
+ emitpcode(POC_MOVFW, popGet(left, 0));
+ emitpcode(POC_BTFSC, popGet(right, 0));
+ emitpcode(POC_DECFW, popGet(left, 0));
+ emitpcode(POC_MOVWF, popGet(result, 0));
}
-
- goto release;
}
-
- if(same) {
-
- if(lit & 0xff) {
- emitpcode(POC_MOVLW, popGetLit(lit & 0xff));
- emitSKPC;
- emitpcode(POC_MOVLW, popGetLit((lit & 0xff)-1));
- emitpcode(POC_SUBWF, popGet(AOP(IC_RESULT(ic)),offset));
- } else {
- emitSKPNC;
- emitpcode(POC_SUBWF, popGet(AOP(IC_RESULT(ic)),offset));
-
- }
- } else {
-
- if(lit & 0xff) {
- emitpcode(POC_MOVLW, popGetLit(lit & 0xff));
- emitpcode(POC_MOVWF, popGet(AOP(IC_RESULT(ic)),offset));
- } else
- emitpcode(POC_CLRF, popGet(AOP(IC_RESULT(ic)),offset));
-
- emitpcode(POC_MOVFW, popGet(AOP(IC_RIGHT(ic)),offset));
- emitSKPC;
- emitpcode(POC_INCFSZW,popGet(AOP(IC_RIGHT(ic)),offset));
- emitpcode(POC_SUBWF, popGet(AOP(IC_RESULT(ic)),offset));
- }
- }
-
-
- } else {
-
- DEBUGpic14_emitcode ("; ","line %d result %s, left %s, right %s",__LINE__,
- AopType(AOP_TYPE(IC_RESULT(ic))),
- AopType(AOP_TYPE(IC_LEFT(ic))),
- AopType(AOP_TYPE(IC_RIGHT(ic))));
-
- if(strcmp(aopGet(AOP(IC_LEFT(ic)),0,FALSE,FALSE),"a") == 0 ) {
- DEBUGpic14_emitcode ("; ***","%s %d",__FUNCTION__,__LINE__);
- emitpcode(POC_SUBFW, popGet(AOP(IC_RIGHT(ic)),0));
- emitpcode(POC_SUBLW, popGetLit(0));
- emitpcode(POC_MOVWF,popGet(AOP(IC_RESULT(ic)),0));
} else {
-
- DEBUGpic14_emitcode ("; ***","%s %d",__FUNCTION__,__LINE__);
- emitpcode(POC_MOVFW,popGet(AOP(IC_RIGHT(ic)),0));
+ fprintf(stderr, "WARNING: subtracting bit from multi-byte operands is incomplete.\n");
+ //exit(EXIT_FAILURE);
+ } // if
+ } else {
+ /*
+ * RIGHT is not a literal and not a bit operand,
+ * LEFT is unknown (register, literal, bit, ...)
+ */
+ lit = 0;
+ isLit = 0;
- if (pic14_sameRegs(AOP(IC_LEFT(ic)), AOP(IC_RESULT(ic))) ) {
- emitpcode(POC_SUBWF, popGet(AOP(IC_LEFT(ic)),0));
+ if(AOP_TYPE(IC_LEFT(ic)) == AOP_LIT) {
+ lit = ulFromVal (left->aopu.aop_lit);
+ isLit = 1;
+ DEBUGpic14_emitcode ("; left is lit","line %d result %s, left %s, right %s",__LINE__,
+ AopType(AOP_TYPE(IC_RESULT(ic))),
+ AopType(AOP_TYPE(IC_LEFT(ic))),
+ AopType(AOP_TYPE(IC_RIGHT(ic))));
+ } // if
+
+
+ /*
+ * First byte, no carry-in.
+ * Any optimizations that are longer than 2 instructions are
+ * useless.
+ */
+ if(same && isLit && ((lit & 0xff) == 0xff)) {
+ // right === res = 0xFF - right = ~right
+ emitpcode(POC_COMF, popGet(right, 0));
+ if(size > 1) {
+ // setup CARRY/#BORROW
+ emitSETC;
+ } // if
+ } else if((size == 1) && isLit && ((lit & 0xff) == 0xff)) {
+ // res = 0xFF - right = ~right
+ emitpcode(POC_COMFW, popGet(right, 0));
+ emitpcode(POC_MOVWF, popGet(result, 0));
+ // CARRY/#BORROW is not setup correctly
+ } else if((size == 1) && same && isLit && ((lit & 0xff) == 0)) {
+ // right === res = 0 - right = ~right + 1
+ emitpcode(POC_COMF, popGet(right, 0));
+ emitpcode(POC_INCF, popGet(right, 0));
+ // CARRY/#BORROW is not setup correctly
+ } else {
+ // general case, should always work
+ mov2w(right, 0);
+ if (pic14_sameRegs(left, result)) {
+ // result === left = left - right (in place)
+ emitpcode(POC_SUBWF, popGet(result, 0));
} else {
- if( (AOP_TYPE(IC_LEFT(ic)) == AOP_IMMD) ||
- (AOP_TYPE(IC_LEFT(ic)) == AOP_LIT) ) {
- emitpcode(POC_SUBLW, popGet(AOP(IC_LEFT(ic)),0));
- } else {
- emitpcode(POC_SUBFW, popGet(AOP(IC_LEFT(ic)),0));
- }
- if ( AOP_TYPE(IC_RESULT(ic)) == AOP_CRY) {
- emitpcode(POC_BCF , popGet(AOP(IC_RESULT(ic)),0));
- emitSKPZ;
- emitpcode(POC_BSF , popGet(AOP(IC_RESULT(ic)),0));
- } else {
- emitpcode(POC_MOVWF,popGet(AOP(IC_RESULT(ic)),0));
- }
- }
- }
+ // works always: result = left - right
+ emitpcode(op_isLitLike(IC_LEFT(ic))
+ ? POC_SUBLW : POC_SUBFW,
+ popGetAddr(left, 0, 0));
+ emitpcode(POC_MOVWF, popGet(result, 0));
+ } // if
+ } // if
- size = min( AOP_SIZE(IC_RESULT(ic)), AOP_SIZE(IC_RIGHT(ic))) - 1;
- offset = 1;
-
- if(size){
- if (pic14_sameRegs(AOP(IC_RIGHT(ic)), AOP(IC_RESULT(ic)))) {
- int lit = 0;
- if (op_isLitLike (IC_LEFT(ic)))
- lit = 1;
- while(size--){
- emitpcode(POC_MOVFW, popGet(AOP(IC_RIGHT(ic)),offset));
- emitSKPC;
- emitpcode(POC_INCFW, popGet(AOP(IC_RIGHT(ic)),offset));
- emitpcode(lit?POC_SUBLW:POC_SUBFW, popGetAddr(AOP(IC_LEFT(ic)),offset,0));
- emitpcode(POC_MOVWF, popGet(AOP(IC_RESULT(ic)),offset));
- offset++;
- }
+ /*
+ * Now for the remaining bytes with carry-in (and carry-out).
+ */
+ offset = 0;
+ while(--size) {
+ lit >>= 8;
+ offset++;
+
+ /*
+ * The following code generation templates are ordered
+ * according to increasing length; the first template
+ * that matches will thus be the shortest and produce
+ * the best code possible with thees templates.
+ */
+
+ if(pic14_sameRegs(left, right)) {
+ /*
+ * This case should not occur; however, the
+ * template works if LEFT, RIGHT, and RESULT are
+ * register operands and LEFT and RIGHT are the
+ * same register(s) and at least as long as the
+ * result.
+ *
+ * CLRF result
+ *
+ * 1 cycle
+ */
+ emitpcode(POC_CLRF, popGet(result, offset));
+ } else if(pic14_sameRegs(left, result)) {
+ /*
+ * This template works if LEFT, RIGHT, and
+ * RESULT are register operands and LEFT and
+ * RESULT are the same register(s).
+ *
+ * MOVF right, W ; W := right
+ * BTFSS STATUS, C
+ * INCFSZ right, W ; W := right + BORROW
+ * SUBWF result, F ; res === left := left - (right + BORROW)
+ *
+ * The SUBWF *must* be skipped if we have a
+ * BORROW bit and right == 0xFF in order to
+ * keep the BORROW bit intact!
+ *
+ * 4 cycles
+ */
+ mov2w(right, offset);
+ emitSKPC;
+ emitpcode(POC_INCFSZW, popGet(right, offset));
+ emitpcode(POC_SUBWF, popGet(result, offset));
+ } else if((size == 1) && isLit && ((lit & 0xff) == 0xff)) {
+ /*
+ * This template works for the last byte (MSB) of
+ * the subtraction and ignores correct propagation
+ * of the outgoing BORROW bit. RIGHT and RESULT
+ * must be register operands, LEFT must be the
+ * literal 0xFF.
+ *
+ * (The case LEFT === RESULT is optimized above.)
+ *
+ * 0xFF - right - BORROW = ~right - BORROW
+ *
+ * COMF right, W ; W := 0xff - right
+ * BTFSS STATUS, C
+ * ADDLW 0xFF ; W := 0xff - right - BORROW
+ * MOVWF result
+ *
+ * 4 cycles
+ */
+ emitpcode(POC_COMFW, popGet(right, offset));
+ emitSKPC;
+ emitpcode(POC_ADDLW, popGetLit(0xff));
+ emitpcode(POC_MOVWF, popGet(result, offset));
+ } else if(size == 1) {
+ /*
+ * This template works for the last byte (MSB) of
+ * the subtraction and ignores correct propagation
+ * of the outgoing BORROW bit. RIGHT and RESULT
+ * must be register operands, LEFT can be a
+ * register or a literal operand.
+ *
+ * (The case LEFT === RESULT is optimized above.)
+ *
+ * MOVF right, W ; W := right
+ * BTFSS STATUS, C
+ * INCF right, W ; W := right + BORROW
+ * SUBxW left, W ; W := left - right - BORROW
+ * MOVWF result
+ *
+ * 5 cycles
+ */
+ mov2w(right, offset);
+ emitSKPC;
+ emitpcode(POC_INCFW, popGet(right, offset));
+ emitpcode(op_isLitLike(IC_LEFT(ic))
+ ? POC_SUBLW : POC_SUBFW,
+ popGetAddr(left, offset, 0));
+ emitpcode(POC_MOVWF, popGet(result, offset));
+ } else if(IS_ITEMP(IC_RESULT(ic))
+ && !pic14_sameRegs(right, result)) {
+ /*
+ * This code template works if RIGHT and RESULT
+ * are different register operands and RESULT
+ * is not volatile/an SFR (written twice).
+ *
+ * #########################################
+ * Since we cannot determine that for sure,
+ * we approximate via IS_ITEMP() for now.
+ * #########################################
+ *
+ * MOVxW left, W ; copy left to result
+ * MOVWF result
+ * MOVF right, W ; W := right
+ * BTFSS STATUS, C
+ * INCFSZ right, W ; W := right + BORROW
+ * SUBWF result, F ; res === left := left - (right + BORROW)
+ *
+ * 6 cycles, but fails for SFR RESULT operands
+ */
+ mov2w(left, offset);
+ emitpcode(POC_MOVWF, popGet(result, offset));
+ mov2w(right, offset);
+ emitSKPC;
+ emitpcode(POC_INCFSZW, popGet(right, offset));
+ emitpcode(POC_SUBWF, popGet(result, offset));
+ } else if(!optimize.codeSize && isLit && ((lit & 0xff) != 0)) {
+ /*
+ * This template works if RIGHT and RESULT are
+ * register operands and LEFT is a literal
+ * operand != 0.
+ *
+ * MOVxW right, W
+ * BTFSC STATUS, C
+ * GOTO next
+ * SUBLW left-1
+ * GOTO common
+ * next:
+ * SUBLW left
+ * common:
+ * MOVWF result
+ *
+ * 6 cycles, 7 iff BORROW
+ * (9 instructions)
+ */
+ lbl_comm = newiTempLabel(NULL);
+ lbl_next = newiTempLabel(NULL);
+
+ mov2w(right, offset);
+ emitSKPNC;
+ emitpcode(POC_GOTO, popGetLabel(lbl_next->key));
+ emitpcode(POC_SUBLW, popGetLit((lit - 1) & 0xff));
+ emitpcode(POC_GOTO, popGetLabel(lbl_comm->key));
+ emitpLabel(lbl_next->key);
+ emitpcode(POC_SUBLW, popGetLit(lit & 0xff));
+ emitpLabel(lbl_comm->key);
+ emitpcode(POC_MOVWF, popGet(result, offset));
} else {
- PIC_OPCODE poc = POC_MOVFW;
- if (op_isLitLike (IC_LEFT(ic)))
- poc = POC_MOVLW;
- while(size--){
- if (!pic14_sameRegs(AOP(IC_LEFT(ic)), AOP(IC_RESULT(ic))) ) {
- emitpcode(poc, popGetAddr(AOP(IC_LEFT(ic)),offset,0));
- emitpcode(POC_MOVWF, popGet(AOP(IC_RESULT(ic)),offset));
- }
- emitpcode(POC_MOVFW, popGet(AOP(IC_RIGHT(ic)),offset));
- emitSKPC;
- emitpcode(POC_INCFSZW,popGet(AOP(IC_RIGHT(ic)),offset));
- emitpcode(POC_SUBWF, popGet(AOP(IC_RESULT(ic)),offset));
- offset++;
- }
- }
- }
- }
+ /*
+ * This code template works if RIGHT and RESULT
+ * are register operands.
+ *
+ * MOVF right, W ; W := right
+ * BTFSS STATUS, C
+ * INCFSZ right, W ; W := right + BORROW
+ * GOTO common
+ * MOVxW left ; if we subtract 0x100 = 0xFF + 1, ...
+ * GOTO next ; res := left, but keep BORROW intact
+ * common:
+ * SUBxW left, W ; W := left - (right + BORROW)
+ * next:
+ * MOVW result ; res := left - (right + BORROW)
+ *
+ * 7 cycles, 8 iff BORROW and (right == 0xFF)
+ * (8 instructions)
+ *
+ *
+ *
+ * Alternative approach using -x = ~x + 1 ==> ~x = -x - 1 = -(x + 1)
+ *
+ * COMFW right, W ; W := -right - (assumed BORROW)
+ * BTFSC STATUS, C ; SKIP if we have a BORROW
+ * ADDLW 1 ; W := -right (no BORROW)
+ * BTFSC STATUS, C ; (***)
+ * MOVLW left ; (***)
+ * BTFSS STATUS, C ; (***)
+ * ADDFW left, W ; W := left - right - BORROW (if any)
+ * MOVWF result ; result := left - right - BORROW (if any)
+ *
+ * 8 cycles
+ *
+ * Case A: C=0 (BORROW)
+ * r=0x00, W=0xFF, W=left+0xFF, C iff left>0x00
+ * r=0x01, W=0xFE, W=left+0xFE, C iff left>0x01
+ * r=0xFE, W=0x01, W=left+0x01, C iff left>0xFE
+ * r=0xFF, W=0x00, W=left+0x00, C iff left>0xFF
+ *
+ * Case B: C=1 (no BORROW)
+ * r=0x00, W=0xFF, W=0x00/C=1, W=left+0x00, C iff left>=0x100 (***)
+ * r=0x01, W=0xFE, W=0xFF/C=0, W=left+0xFF, C iff left>=0x01
+ * r=0xFE, W=0x01, W=0x02/C=0, W=left+0x02, C iff left>=0xFE
+ * r=0xFF, W=0x00, W=0x01/C=0, W=left+0x01, C iff left>=0xFF
+ */
+ lbl_comm = newiTempLabel(NULL);
+ lbl_next = newiTempLabel(NULL);
+
+ mov2w(right, offset);
+ emitSKPC;
+ emitpcode(POC_INCFSZW, popGet(right, offset));
+ emitpcode(POC_GOTO, popGetLabel(lbl_comm->key));
+ mov2w(left, offset);
+ emitpcode(POC_GOTO, popGetLabel(lbl_next->key));
+ emitpLabel(lbl_comm->key);
+ emitpcode(op_isLitLike(IC_LEFT(ic))
+ ? POC_SUBLW : POC_SUBFW,
+ popGetAddr(left, offset, 0));
+ emitpLabel(lbl_next->key);
+ emitpcode(POC_MOVWF, popGet(result, offset));
+ } // if
+ } // while
+ } // if
+
+ if(AOP_TYPE(IC_RESULT(ic)) == AOP_CRY) {
+ fprintf(stderr, "WARNING: AOP_CRY (bit-) results are probably broken. Please report this with source code as a bug.\n");
+ mov2w(result, 0); // load Z flag
+ emitpcode(POC_BCF, popGet(result, 0));
+ emitSKPZ;
+ emitpcode(POC_BSF, popGet(result, 0));
+ } // if
// adjustArithmeticResult(ic);
freeAsmop(IC_RIGHT(ic),NULL,ic,(RESULTONSTACK(ic) ? FALSE : TRUE));
freeAsmop(IC_RESULT(ic),NULL,ic,TRUE);
}
-/*-----------------------------------------------------------------*
-* genUMult8XLit_16 - unsigned multiplication of two 8-bit numbers.
-*
-*
-*-----------------------------------------------------------------*/
-void genUMult8XLit_16 (operand *left,
- operand *right,
- operand *result,
- pCodeOpReg *result_hi)
-
-{
-
- unsigned int lit;
- unsigned int i,have_first_bit;
- int same;
- pCodeOp *temp;
-
- FENTRY;
- if (AOP_TYPE(right) != AOP_LIT){
- fprintf(stderr,"%s %d - right operand is not a literal\n",__FILE__,__LINE__);
- exit(EXIT_FAILURE);
- }
-
-
- if(!result_hi) {
- result_hi = PCOR(popGet(AOP(result),1));
- }
-
- lit = (unsigned int) ulFromVal (AOP(right)->aopu.aop_lit);
- lit &= 0xff;
- pic14_emitcode(";","Unrolled 8 X 8 multiplication");
-
- same = pic14_sameRegs(AOP(left), AOP(result));
-
- if(same) {
- switch(lit) {
- case 0:
- emitpcode(POC_CLRF, popGet(AOP(left),0));
- return;
- case 2:
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_ADDWF, popGet(AOP(left),0));
- return;
- case 3:
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_ADDWF, popGet(AOP(left),0));
- emitpcode(POC_ADDWF, popGet(AOP(left),0));
- return;
- case 4:
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_ADDWF, popGet(AOP(left),0));
- emitpcode(POC_ADDWF, popGet(AOP(left),0));
- emitpcode(POC_ADDWF, popGet(AOP(left),0));
- return;
- case 5:
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_ADDFW, popGet(AOP(left),0)); // W = 2*F
- emitpcode(POC_ADDWF, popGet(AOP(left),0)); // F = 3*F
- emitpcode(POC_ADDWF, popGet(AOP(left),0)); // F = 5*F
- return;
- case 6:
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_ADDWF, popGet(AOP(left),0));
- emitpcode(POC_ADDWF, popGet(AOP(left),0));
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_ADDWF, popGet(AOP(left),0));
- return;
- case 7:
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_ADDFW, popGet(AOP(left),0)); // W = 2*F
- emitpcode(POC_ADDWF, popGet(AOP(left),0)); // F = 3*F
- emitpcode(POC_ADDWF, popGet(AOP(left),0)); // F = 5*F
- emitpcode(POC_ADDWF, popGet(AOP(left),0)); // F = 7*F
- return;
- case 8:
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_ADDFW, popGet(AOP(left),0)); // W = 2*F
- emitpcode(POC_ADDWF, popGet(AOP(left),0)); // F = 3*F
- emitpcode(POC_ADDFW, popGet(AOP(left),0)); // W = 5*F
- emitpcode(POC_ADDWF, popGet(AOP(left),0)); // F = 8*F
- return;
- case 9:
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_ADDWF, popGet(AOP(left),0));
- emitpcode(POC_ADDWF, popGet(AOP(left),0));
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_ADDWF, popGet(AOP(left),0));
- emitpcode(POC_ADDWF, popGet(AOP(left),0));
- return;
- case 10:
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_ADDFW, popGet(AOP(left),0)); // W = 2*F
- emitpcode(POC_ADDWF, popGet(AOP(left),0)); // F = 3*F
- emitpcode(POC_ADDWF, popGet(AOP(left),0)); // F = 5*F
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_ADDWF, popGet(AOP(left),0));
- return;
- case 11:
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_ADDFW, popGet(AOP(left),0)); // W = 2*F
- emitpcode(POC_ADDWF, popGet(AOP(left),0)); // F = 3*F
- emitpcode(POC_ADDFW, popGet(AOP(left),0)); // W = 5*F
- emitpcode(POC_ADDFW, popGet(AOP(left),0)); // W = 8*F
- emitpcode(POC_ADDWF, popGet(AOP(left),0)); // F = 11*F
- return;
- case 12:
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_ADDWF, popGet(AOP(left),0));
- emitpcode(POC_ADDWF, popGet(AOP(left),0));
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_ADDWF, popGet(AOP(left),0));
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_ADDWF, popGet(AOP(left),0));
- return;
- case 13:
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_ADDFW, popGet(AOP(left),0)); // W = 2*F
- emitpcode(POC_ADDWF, popGet(AOP(left),0)); // F = 3*F
- emitpcode(POC_ADDFW, popGet(AOP(left),0)); // W = 5*F
- emitpcode(POC_ADDWF, popGet(AOP(left),0)); // F = 8*F
- emitpcode(POC_ADDWF, popGet(AOP(left),0)); // F = 13*F
- return;
- case 14:
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_ADDFW, popGet(AOP(left),0)); // W = 2*F
- emitpcode(POC_ADDWF, popGet(AOP(left),0)); // F = 3*F
- emitpcode(POC_ADDFW, popGet(AOP(left),0)); // W = 5*F
- emitpcode(POC_ADDFW, popGet(AOP(left),0)); // W = 8*F
- emitpcode(POC_ADDFW, popGet(AOP(left),0)); // W = 11*F
- emitpcode(POC_ADDWF, popGet(AOP(left),0)); // F = 14*F
- return;
- case 15:
- temp = popGetTempReg();
- if(!temp) {
- fprintf(stderr,"ERROR: unable to allocate register. %s:%d\n",__FUNCTION__,__LINE__);
- exit(EXIT_FAILURE);
- }
- emitpcode(POC_SWAPFW, popGet(AOP(left),0));
- emitpcode(POC_MOVWF, temp);
- emitpcode(POC_ANDLW, popGetLit(0xf0));
- emitpcode(POC_MOVWF, popGet(AOP(left),0));
- emitpcode(POC_SWAPFW, temp);
- emitpcode(POC_SUBWF, popGet(AOP(left),0));
- popReleaseTempReg(temp);
- return;
- case 16:
- emitpcode(POC_SWAPFW, popGet(AOP(left),0));
- emitpcode(POC_ANDLW, popGetLit(0xf0));
- emitpcode(POC_MOVWF, popGet(AOP(left),0));
- return;
- case 17:
- emitpcode(POC_SWAPFW, popGet(AOP(left),0));
- emitpcode(POC_ANDLW, popGetLit(0xf0));
- emitpcode(POC_ADDWF, popGet(AOP(left),0));
- return;
- case 32:
- emitpcode(POC_SWAPF, popGet(AOP(left),0));
- emitpcode(POC_RLFW, popGet(AOP(left),0));
- emitpcode(POC_ANDLW, popGetLit(0xe0));
- emitpcode(POC_MOVWF, popGet(AOP(left),0));
- return;
- case 64:
- emitpcode(POC_SWAPF, popGet(AOP(left),0));
- emitpcode(POC_RLF, popGet(AOP(left),0));
- emitpcode(POC_RLFW, popGet(AOP(left),0));
- emitpcode(POC_ANDLW, popGetLit(0xc0));
- emitpcode(POC_MOVWF, popGet(AOP(left),0));
- return;
- case 128:
- emitpcode(POC_RRFW, popGet(AOP(left),0));
- emitpcode(POC_CLRF, popGet(AOP(left),0));
- emitpcode(POC_RRF, popGet(AOP(left),0));
- return;
-
- }
- } else {
-
- switch(lit) {
- case 0:
- emitpcode(POC_CLRF, popGet(AOP(result),0));
- emitpcode(POC_CLRF, popCopyReg(result_hi));
- return;
- case 2:
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_MOVWF, popGet(AOP(result),0));
- emitpcode(POC_ADDWF, popGet(AOP(result),0));
- emitpcode(POC_CLRF, popCopyReg(result_hi));
- emitpcode(POC_RLF, popCopyReg(result_hi));
- return;
- case 4:
- case 8:
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_MOVWF, popGet(AOP(result),0));
- emitpcode(POC_CLRF, popCopyReg(result_hi));
- emitpcode(POC_BCF, popCopyReg(&pc_status));
- emitpcode(POC_RLF, popGet(AOP(result),0));
- emitpcode(POC_RLF, popCopyReg(result_hi));
- emitpcode(POC_RLF, popGet(AOP(result),0));
- emitpcode(POC_RLF, popCopyReg(result_hi));
- if (lit >= 8) {
- emitpcode(POC_RLF, popGet(AOP(result),0));
- emitpcode(POC_RLF, popCopyReg(result_hi));
- }
- return;
- }
-
- }
-
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_CLRF, popGet(AOP(result),0));
- emitpcode(POC_CLRF, popCopyReg(result_hi));
-
- have_first_bit = 0;
- for(i=0; i<8; i++) {
-
- if(lit & 1) {
- emitpcode(POC_ADDWF, popCopyReg(result_hi));
- have_first_bit = 1;
- }
-
- if(have_first_bit) {
- emitpcode(POC_RRF, popCopyReg(result_hi));
- emitpcode(POC_RRF, popGet(AOP(result),0));
- }
-
- lit >>= 1;
- }
-}
-/*-----------------------------------------------------------------*
-* genUMult8X8_16 - unsigned multiplication of two 8-bit numbers.
-*
-*
-*-----------------------------------------------------------------*/
-void genUMult8X8_16 (operand *left,
- operand *right,
- operand *result,
- pCodeOpReg *result_hi)
-
-{
-
- int i;
- int looped = 1;
-
- FENTRY;
- if(!result_hi) {
- result_hi = PCOR(popGet(AOP(result),1));
- }
-
- if (AOP_TYPE(right) == AOP_LIT) {
- genUMult8XLit_16(left,right,result,result_hi);
- return;
- }
-
- if(!looped) {
- pic14_emitcode(";","Unrolled 8 X 8 multiplication");
-
- emitpcode(POC_MOVFW, popGet(AOP(right),0));
- emitpcode(POC_CLRF, popGet(AOP(result),0));
- emitpcode(POC_CLRF, popCopyReg(result_hi));
- emitCLRC;
-
- for(i=0; i<8; i++) {
- emitpcode(POC_BTFSC, newpCodeOpBit(aopGet(AOP(left),0,FALSE,FALSE),i,0));
- emitpcode(POC_ADDWF, popCopyReg(result_hi));
- emitpcode(POC_RRF, popCopyReg(result_hi));
- emitpcode(POC_RRF, popGet(AOP(result),0));
- }
-
-
- /*
- Here's another version that does the same thing and takes the
- same number of instructions. The one above is slightly better
- because the entry instructions have a higher probability of
- being optimized out.
- */
- /*
- emitpcode(POC_CLRF, popCopyReg(result_hi));
- emitpcode(POC_RRFW, popGet(AOP(left),0));
- emitpcode(POC_MOVWF, popGet(AOP(result),0));
- emitpcode(POC_MOVFW, popGet(AOP(right),0));
-
- for(i=0; i<8; i++) {
- emitSKPNC;
- emitpcode(POC_ADDWF, popCopyReg(result_hi));
- emitpcode(POC_RRF, popCopyReg(result_hi));
- emitpcode(POC_RRF, popGet(AOP(result),0));
- }
- */
-
- } else {
- symbol *tlbl = newiTempLabel(NULL);
- pCodeOp *temp;
-
-
- pic14_emitcode(";","Looped 8 X 8 multiplication");
-
- emitpcode(POC_CLRF, popGet(AOP(result),0));
- emitpcode(POC_CLRF, popCopyReg(result_hi));
-
- emitpcode(POC_BSF, newpCodeOpBit(aopGet(AOP(result),0,FALSE,FALSE),7,0));
-
- emitpcode(POC_MOVFW, popGet(AOP(right),0));
-
- temp = popGetTempReg();
- emitpcode(POC_MOVWF, popCopyReg(PCOR(temp)));
-
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
-
- emitpLabel(tlbl->key);
-
- emitpcode(POC_RRF, popCopyReg(PCOR(temp)));
- emitSKPNC;
- emitpcode(POC_ADDWF, popCopyReg(result_hi));
-
- emitpcode(POC_RRF, popCopyReg(result_hi));
- emitpcode(POC_RRF, popGet(AOP(result),0));
-
- emitSKPC;
- emitpcode(POC_GOTO, popGetLabel(tlbl->key));
-
- popReleaseTempReg(temp);
-
- }
-}
-
-/*-----------------------------------------------------------------*
-* genSMult8X8_16 - signed multiplication of two 8-bit numbers
-*
-* this routine will call the unsigned multiply routine and then
-* post-fix the sign bit.
-*-----------------------------------------------------------------*/
-void genSMult8X8_16 (operand *left,
- operand *right,
- operand *result,
- pCodeOpReg *result_hi)
-{
-
- FENTRY;
- if(!result_hi) {
- result_hi = PCOR(popGet(AOP(result),1));
- }
-
- genUMult8X8_16(left,right,result,result_hi);
-
- emitpcode(POC_BTFSC, newpCodeOpBit(aopGet(AOP(left),0,FALSE,FALSE),7,0));
- emitpcode(POC_SUBWF, popCopyReg(result_hi));
- emitpcode(POC_MOVFW, popGet(AOP(left),0));
- emitpcode(POC_BTFSC, newpCodeOpBit(aopGet(AOP(right),0,FALSE,FALSE),7,0));
- emitpcode(POC_SUBWF, popGet(AOP(result),1));
-
-}
-
-/*-----------------------------------------------------------------*
-* genMult8X8_8 - multiplication of two 8-bit numbers
-*
-* this routine will call the unsigned multiply 8X8=>16 routine and
-* then throw away the high byte of the result.
-*
-*-----------------------------------------------------------------*/
-void genMult8X8_8 (operand *left,
- operand *right,
- operand *result)
-{
- pCodeOp *result_hi;
- FENTRY;
- if (result && result->aop && result->aop->type==2 && result->aop->size>=1) {
- result->aop->aopu.aop_reg[0]->isFree = 0; /* Sometimes (ie part of last instruction in a blk) the result reg is pre marked as free, which mean on the next line popGetTempReg() will return this reg instead of allocating a new one. */
- }
- result_hi = popGetTempReg();
-
- if (AOP_TYPE(right) == AOP_LIT)
- genUMult8XLit_16(left,right,result,PCOR(result_hi));
- else
- genUMult8X8_16(left,right,result,PCOR(result_hi));
-
- popReleaseTempReg(result_hi);
-}
-#if 0
-/*-----------------------------------------------------------------*/
-/* constMult - generates code for multiplication by a constant */
-/*-----------------------------------------------------------------*/
-void genMultConst(unsigned C)
-{
-
- unsigned lit;
- unsigned sr3; // Shift right 3
- unsigned mask;
-
- int size = 1;
-
- /*
- Convert a string of 3 binary 1's in the lit into
- 0111 = 1000 - 1;
- */
-
- mask = 7 << ( (size*8) - 3);
- lit = C;
- sr3 = 0;
-
- while(mask < (1<<size*8)) {
-
- if( (mask & lit) == lit) {
- unsigned lsb;
-
- /* We found 3 (or more) consecutive 1's */
-
- lsb = mask & ~(mask & (mask-1)); // lsb of mask.
-
- consecutive_bits = ((lit + lsb) & lit) ^ lit;
-
- lit ^= consecutive_bits;
-
- mask <<= 3;
-
- sr3 |= (consecutive + lsb);
-
- }
-
- mask >>= 1;
-
- }
-
-}
-
-#endif
projects / fw / sdcc / commitdiff