even more code improvement

R=r
OCL=21160
CL=21160

src/cmd/6g/gen.c

@@ -915,55 +915,96 @@ cgen_asop(Node *n)
 {
 	Node n1, n2, n3, n4;
 	Node *nl, *nr;
+	Prog *p1;
+	Addr addr;
 
 	nl = n->left;
 	nr = n->right;
 
-	if(nl->addable && nr->op == OLITERAL)
+	if(nr->ullman >= UINF && nl->ullman >= UINF) {
+		tempname(&n1, nr->type);
+		cgen(nr, &n1);
+		n2 = *n;
+		n2.right = &n1;
+		cgen_asop(&n2);
+		goto ret;
+	}
+
+	if(!isint[nl->type->etype])
+		goto hard;
+	if(!isint[nr->type->etype])
+		goto hard;
+
 	switch(n->etype) {
 	case OADD:
-		if(!isint[nl->type->etype])
-			break;
-		if(mpgetfix(nr->val.u.xval) != 1)
-			break;
+		if(smallintconst(nr))
+		if(mpgetfix(nr->val.u.xval) == 1) {
+			if(nl->addable) {
 				gins(optoas(OINC, nl->type), N, nl);
 				goto ret;
-	case OSUB:
-		if(!isint[nl->type->etype])
-			break;
-		if(mpgetfix(nr->val.u.xval) != 1)
+			}
+			if(sudoaddable(nl, nr->type, &addr)) {
+				p1 = gins(optoas(OINC, nl->type), N, N);
+				p1->to = addr;
+				sudoclean();
+				goto ret;
+			}
+		}
 		break;
+
+	case OSUB:
+		if(smallintconst(nr))
+		if(mpgetfix(nr->val.u.xval) == 1) {
+			if(nl->addable) {
 				gins(optoas(ODEC, nl->type), N, nl);
 				goto ret;
 			}
+			if(sudoaddable(nl, nr->type, &addr)) {
+				p1 = gins(optoas(ODEC, nl->type), N, N);
+				p1->to = addr;
+				sudoclean();
+				goto ret;
+			}
+		}
+		break;
+	}
 
-	if(nl->addable)
 	switch(n->etype) {
+	case OADD:
+	case OSUB:
 	case OXOR:
 	case OAND:
 	case OOR:
-	case OADD:
-	case OSUB:
-		if(!isint[nl->type->etype])
-			break;
-		if(!isint[nr->type->etype])
-			break;
+		if(nl->addable) {
+			if(smallintconst(nr)) {
+				gins(optoas(n->etype, nl->type), nr, nl);
+				goto ret;
+			}
 			regalloc(&n2, nr->type, N);
 			cgen(nr, &n2);
 			gins(optoas(n->etype, nl->type), &n2, nl);
 			regfree(&n2);
 			goto ret;
 		}
-
-	if(nr->ullman >= UINF && nl->ullman >= UINF) {
-		tempname(&n1, nr->type);
-		cgen(nr, &n1);
-		n2 = *n;
-		n2.right = &n1;
-		cgen_asop(&n2);
+		if(nr->ullman < UINF)
+		if(sudoaddable(nl, nr->type, &addr)) {
+			if(smallintconst(nr)) {
+				p1 = gins(optoas(n->etype, nl->type), nr, N);
+				p1->to = addr;
+				sudoclean();
 				goto ret;
 			}
+			regalloc(&n2, nr->type, N);
+			cgen(nr, &n2);
+			p1 = gins(optoas(n->etype, nl->type), &n2, N);
+			p1->to = addr;
+			regfree(&n2);
+			sudoclean();
+			goto ret;
+		}
+	}
 
+hard:
 	if(nr->ullman > nl->ullman) {
 		regalloc(&n2, nr->type, N);
 		cgen(nr, &n2);

src/cmd/6g/gg.h

@@ -199,7 +199,6 @@ void	tempname(Node*, Type*);
 Plist*	newplist(void);
 int	isfat(Type*);
 void	setmaxarg(Type*);
-int	smallintconst(Node*);
 void	sudoclean(void);
 int	sudoaddable(Node*, Type*, Addr*);
 

src/cmd/6g/gsubr.c

@@ -102,6 +102,19 @@ newplist(void)
 	return pl;
 }
 
+static	int	resvd[] =
+{
+//	D_DI,	// for movstring
+//	D_SI,	// for movstring
+
+	D_AX,	// for divide
+	D_CX,	// for shift
+	D_DX,	// for divide
+	D_SP,	// for stack
+	D_R14,	// reserved for m
+	D_R15,	// reserved for u
+};
+
 void
 ginit(void)
 {
@@ -114,15 +127,8 @@ ginit(void)
 	for(i=D_X0; i<=D_X7; i++)
 		reg[i] = 0;
 
-//	reg[D_DI]++;	// for movstring
-//	reg[D_SI]++;	// for movstring
-
-	reg[D_AX]++;	// for divide
-	reg[D_CX]++;	// for shift
-	reg[D_DX]++;	// for divide
-	reg[D_SP]++;	// for stack
-	reg[D_R14]++;	// reserved for m
-	reg[D_R15]++;	// reserved for u
+	for(i=0; i<nelem(resvd); i++)
+		reg[resvd[i]]++;
 }
 
 void
@@ -130,15 +136,8 @@ gclean(void)
 {
 	int i;
 
-//	reg[D_DI]--;	// for movstring
-//	reg[D_SI]--;	// for movstring
-
-	reg[D_AX]--;	// for divide
-	reg[D_CX]--;	// for shift
-	reg[D_DX]--;	// for divide
-	reg[D_SP]--;	// for stack
-	reg[D_R14]--;	// reserved for m
-	reg[D_R15]--;	// reserved for u
+	for(i=0; i<nelem(resvd); i++)
+		reg[resvd[i]]--;
 
 	for(i=D_AX; i<=D_R15; i++)
 		if(reg[i])
@@ -1817,24 +1816,6 @@ dotoffset(Node *n, int *oary, Node **nn)
 	return i;
 }
 
-int
-smallintconst(Node *n)
-{
-	if(n->op == OLITERAL)
-	switch(simtype[n->type->etype]) {
-	case TINT8:
-	case TUINT8:
-	case TINT16:
-	case TUINT16:
-	case TINT32:
-	case TUINT32:
-	case TBOOL:
-	case TPTR32:
-		return 1;
-	}
-	return 0;
-}
-
 enum
 {
 	ODynam	= 1<<0,
@@ -1857,37 +1838,36 @@ sudoclean(void)
 int
 sudoaddable(Node *n, Type *t, Addr *a)
 {
-	int et, o, i, w;
+	int o, i, w;
 	int oary[10];
 	vlong v;
-	Node n0, n1, n2, *nn, *l, *r;
+	Node n1, n2, *nn, *l, *r;
 	Node *reg, *reg1;
 	Prog *p1;
 
-	// make a cleanup slot
-	cleani += 2;
-	reg = &clean[cleani-1];
-	reg1 = &clean[cleani-2];
-	reg->op = OEMPTY;
-	reg1->op = OEMPTY;
-
 	if(n->type == T || t == T)
-		goto no;
-	et = simtype[n->type->etype];
-	if(et != simtype[t->etype])
-		goto no;
+		return 0;
 
 	switch(n->op) {
 	default:
-		goto no;
+		return 0;
 
 	case ODOT:
 	case ODOTPTR:
+		cleani += 2;
+		reg = &clean[cleani-1];
+		reg1 = &clean[cleani-2];
+		reg->op = OEMPTY;
+		reg1->op = OEMPTY;
 		goto odot;
 
 	case OINDEXPTR:
-		goto no;
 	case OINDEX:
+		cleani += 2;
+		reg = &clean[cleani-1];
+		reg1 = &clean[cleani-2];
+		reg->op = OEMPTY;
+		reg1->op = OEMPTY;
 		goto oindex;
 	}
 
@@ -1896,15 +1876,6 @@ odot:
 	if(nn == N)
 		goto no;
 	
-	if(0) {
-		dump("\nXX", n);
-		dump("YY", nn);
-		for(i=0; i<o; i++)
-			print(" %d", oary[i]);
-		print("\n");
-		goto no;
-	}
-	
 	regalloc(reg, types[tptr], N);
 	n1 = *reg;
 	n1.op = OINDREG;
@@ -1931,7 +1902,7 @@ odot:
 oindex:
 	l = n->left;
 	r = n->right;
-	if(l->ullman >= UINF || r->ullman >= UINF)
+	if(l->ullman >= UINF && r->ullman >= UINF)
 		goto no;
 
 	// set o to type of array
@@ -1950,8 +1921,6 @@ oindex:
 	}
 
 	w = n->type->width;
-	if(w == 0)
-		fatal("index is zero width");
 	if(whatis(r) == Wlitint)
 		goto oindex_const;
 

src/cmd/gc/const.c

@@ -540,3 +540,21 @@ cmpslit(Node *l, Node *r)
 		return +1;
 	return -1;
 }
+
+int
+smallintconst(Node *n)
+{
+	if(n->op == OLITERAL)
+	switch(simtype[n->type->etype]) {
+	case TINT8:
+	case TUINT8:
+	case TINT16:
+	case TUINT16:
+	case TINT32:
+	case TUINT32:
+	case TBOOL:
+	case TPTR32:
+		return 1;
+	}
+	return 0;
+}

src/cmd/gc/go.h

@@ -826,6 +826,7 @@ void	convlit1(Node*, Type*, int);
 void	convlit(Node*, Type*);
 void	evconst(Node*);
 int	cmpslit(Node *l, Node *r);
+int	smallintconst(Node*);
 
 /*
  *	gen.c/gsubr.c/obj.c