add TST op code

R=r
CC=golang-dev
https://golang.org/cl/4000041

src/cmd/5g/cgen.c

@@ -671,7 +671,8 @@ agen(Node *n, Node *res)
 			p1 = gins(AMOVW, N, &n3);
 			datastring(nl->val.u.sval->s, nl->val.u.sval->len, &p1->from);
 			p1->from.type = D_CONST;
-		} else if(isslice(nl->type) || nl->type->etype == TSTRING) {
+		} else
+		if(isslice(nl->type) || nl->type->etype == TSTRING) {
 			n1 = n3;
 			n1.op = OINDREG;
 			n1.type = types[tptr];
@@ -813,6 +814,28 @@ agenr(Node *n, Node *a, Node *res)
 	agen(n, a);
 }
 
+void
+gencmp0(Node *n, Type *t, int o, Prog *to)
+{
+	Node n1, n2, n3;
+	int a;
+
+	regalloc(&n1, t, N);
+	cgen(n, &n1);
+	a = optoas(OCMP, t);
+	if(a != ACMP) {
+		nodconst(&n2, t, 0);
+		regalloc(&n3, t, N);
+		gmove(&n2, &n3);
+		gcmp(a, &n1, &n3);
+		regfree(&n3);
+	} else
+		gins(ATST, &n1, N);
+	a = optoas(o, t);
+	patch(gbranch(optoas(o, t), t), to);
+	regfree(&n1);
+}
+
 /*
  * generate:
  *	if(n == true) goto to;
@@ -856,18 +879,10 @@ bgen(Node *n, int true, Prog *to)
 	switch(n->op) {
 	default:
 	def:
-		regalloc(&n1, n->type, N);
-		cgen(n, &n1);
-		nodconst(&n2, n->type, 0);
-		regalloc(&n3, n->type, N);
-		gmove(&n2, &n3);
-		gcmp(optoas(OCMP, n->type), &n1, &n3);
-		a = ABNE;
+		a = ONE;
 		if(!true)
-			a = ABEQ;
-		patch(gbranch(a, n->type), to);
-		regfree(&n1);
-		regfree(&n3);
+			a = OEQ;
+		gencmp0(n, n->type, a, to);
 		goto ret;
 
 	case OLITERAL:
@@ -876,23 +891,6 @@ bgen(Node *n, int true, Prog *to)
 			patch(gbranch(AB, T), to);
 		goto ret;
 
-	case ONAME:
-		if(n->addable == 0)
-			goto def;
-		nodconst(&n1, n->type, 0);
-		regalloc(&n2, n->type, N);
-		regalloc(&n3, n->type, N);
-		gmove(&n1, &n2);
-		cgen(n, &n3);
-		gcmp(optoas(OCMP, n->type), &n2, &n3);
-		a = ABNE;
-		if(!true)
-			a = ABEQ;
-		patch(gbranch(a, n->type), to);
-		regfree(&n2);
-		regfree(&n3);
-		goto ret;
-
 	case OANDAND:
 		if(!true)
 			goto caseor;
@@ -975,6 +973,16 @@ bgen(Node *n, int true, Prog *to)
 				yyerror("illegal array comparison");
 				break;
 			}
+
+			regalloc(&n1, types[tptr], N);
+			agen(nl, &n1);
+			n2 = n1;
+			n2.op = OINDREG;
+			n2.xoffset = Array_array;
+			gencmp0(&n2, types[tptr], a, to);
+			regfree(&n1);
+			break;
+
 			a = optoas(a, types[tptr]);
 			regalloc(&n1, types[tptr], N);
 			regalloc(&n3, types[tptr], N);
@@ -1000,6 +1008,16 @@ bgen(Node *n, int true, Prog *to)
 				yyerror("illegal interface comparison");
 				break;
 			}
+
+			regalloc(&n1, types[tptr], N);
+			agen(nl, &n1);
+			n2 = n1;
+			n2.op = OINDREG;
+			n2.xoffset = 0;
+			gencmp0(&n2, types[tptr], a, to);
+			regfree(&n1);
+			break;
+
 			a = optoas(a, types[tptr]);
 			regalloc(&n1, types[tptr], N);
 			regalloc(&n3, types[tptr], N);
@@ -1039,6 +1057,17 @@ bgen(Node *n, int true, Prog *to)
 			break;
 		}
 
+		if(nr->op == OLITERAL) {
+			if(nr->val.ctype == CTINT &&  mpgetfix(nr->val.u.xval) == 0) {
+				gencmp0(nl, nl->type, a, to);
+				break;
+			}
+			if(nr->val.ctype == CTNIL) {
+				gencmp0(nl, nl->type, a, to);
+				break;
+			}
+		}
+
 		a = optoas(a, nr->type);
 
 		if(nr->ullman >= UINF) {

src/cmd/5g/cgen64.c

@@ -233,8 +233,7 @@ cgen64(Node *n, Node *res)
 			// shift is >= 1<<32
 			split64(r, &cl, &ch);
 			gmove(&ch, &s);
-			p1 = gins(AMOVW, &s, &s);
-			p1->scond |= C_SBIT;
+			p1 = gins(ATST, &s, N);
 			p6 = gbranch(ABNE, T);
 			gmove(&cl, &s);
 			splitclean();
@@ -242,8 +241,7 @@ cgen64(Node *n, Node *res)
 			gmove(r, &s);
 			p6 = P;
 		}
-		p1 = gins(AMOVW, &s, &s);
-		p1->scond |= C_SBIT;
+		p1 = gins(ATST, &s, N);
 
 		// shift == 0
 		p1 = gins(AMOVW, &bl, &al);
@@ -390,8 +388,7 @@ olsh_break:
 			// shift is >= 1<<32
 			split64(r, &cl, &ch);
 			gmove(&ch, &s);
-			p1 = gins(AMOVW, &s, &s);
-			p1->scond |= C_SBIT;
+			p1 = gins(ATST, &s, N);
 			p6 = gbranch(ABNE, T);
 			gmove(&cl, &s);
 			splitclean();
@@ -399,8 +396,7 @@ olsh_break:
 			gmove(r, &s);
 			p6 = P;
 		}
-		p1 = gins(AMOVW, &s, &s);
-		p1->scond |= C_SBIT;
+		p1 = gins(ATST, &s, N);
 
 		// shift == 0
 		p1 = gins(AMOVW, &bl, &al);

src/cmd/5g/ggen.c

@@ -595,8 +595,7 @@ cgen_shift(int op, Node *nl, Node *nr, Node *res)
 	}
 
 	// test for shift being 0
-	p1 = gins(AMOVW, &n1, &n1);
-	p1->scond |= C_SBIT;
+	p1 = gins(ATST, &n1, N);
 	p3 = gbranch(ABEQ, T);
 
 	// test and fix up large shifts

src/cmd/5g/peep.c

@@ -89,11 +89,11 @@ loop1:
 			/*
 			 * elide shift into D_SHIFT operand of subsequent instruction
 			 */
-			if(shiftprop(r)) {
-				excise(r);
-				t++;
-				break;
-			}
+//			if(shiftprop(r)) {
+//				excise(r);
+//				t++;
+//				break;
+//			}
 			break;
 
 		case AMOVW:
@@ -101,10 +101,10 @@ loop1:
 		case AMOVD:
 			if(!regtyp(&p->to))
 				break;
-			if(isdconst(&p->from)) {
-				constprop(&p->from, &p->to, r->s1);
-				break;
-			}
+//			if(isdconst(&p->from)) {
+//				constprop(&p->from, &p->to, r->s1);
+//				break;
+//			}
 			if(!regtyp(&p->from))
 				break;
 			if(p->from.type != p->to.type)
@@ -166,87 +166,89 @@ loop1:
 		excise(r1);
 	}
 
-	for(r=firstr; r!=R; r=r->link) {
-		p = r->prog;
-		switch(p->as) {
-		case AMOVW:
-		case AMOVB:
-		case AMOVBU:
-			if(p->from.type == D_OREG && p->from.offset == 0)
-				xtramodes(r, &p->from);
-			else if(p->to.type == D_OREG && p->to.offset == 0)
-				xtramodes(r, &p->to);
-			else
-				continue;
-			break;
-		case ACMP:
-			/*
-			 * elide CMP $0,x if calculation of x can set condition codes
-			 */
-			if(isdconst(&p->from) || p->from.offset != 0)
-				continue;
-			r2 = r->s1;
-			if(r2 == R)
-				continue;
-			t = r2->prog->as;
-			switch(t) {
-			default:
-				continue;
-			case ABEQ:
-			case ABNE:
-			case ABMI:
-			case ABPL:
-				break;
-			case ABGE:
-				t = ABPL;
-				break;
-			case ABLT:
-				t = ABMI;
-				break;
-			case ABHI:
-				t = ABNE;
-				break;
-			case ABLS:
-				t = ABEQ;
-				break;
-			}
-			r1 = r;
-			do
-				r1 = uniqp(r1);
-			while (r1 != R && r1->prog->as == ANOP);
-			if(r1 == R)
-				continue;
-			p1 = r1->prog;
-			if(p1->to.type != D_REG)
-				continue;
-			if(p1->to.reg != p->reg)
-			if(!(p1->as == AMOVW && p1->from.type == D_REG && p1->from.reg == p->reg))
-				continue;
-			switch(p1->as) {
-			default:
-				continue;
-			case AMOVW:
-				if(p1->from.type != D_REG)
-					continue;
-			case AAND:
-			case AEOR:
-			case AORR:
-			case ABIC:
-			case AMVN:
-			case ASUB:
-			case ARSB:
-			case AADD:
-			case AADC:
-			case ASBC:
-			case ARSC:
-				break;
-			}
-			p1->scond |= C_SBIT;
-			r2->prog->as = t;
-			excise(r);
-			continue;
-		}
-	}
+//	for(r=firstr; r!=R; r=r->link) {
+//		p = r->prog;
+//		switch(p->as) {
+//		case AMOVW:
+//		case AMOVB:
+//		case AMOVBU:
+//			if(p->from.type == D_OREG && p->from.offset == 0)
+//				xtramodes(r, &p->from);
+//			else
+//			if(p->to.type == D_OREG && p->to.offset == 0)
+//				xtramodes(r, &p->to);
+//			else
+//				continue;
+//			break;
+//		case ACMP:
+//			/*
+//			 * elide CMP $0,x if calculation of x can set condition codes
+//			 */
+//			if(isdconst(&p->from) || p->from.offset != 0)
+//				continue;
+//			r2 = r->s1;
+//			if(r2 == R)
+//				continue;
+//			t = r2->prog->as;
+//			switch(t) {
+//			default:
+//				continue;
+//			case ABEQ:
+//			case ABNE:
+//			case ABMI:
+//			case ABPL:
+//				break;
+//			case ABGE:
+//				t = ABPL;
+//				break;
+//			case ABLT:
+//				t = ABMI;
+//				break;
+//			case ABHI:
+//				t = ABNE;
+//				break;
+//			case ABLS:
+//				t = ABEQ;
+//				break;
+//			}
+//			r1 = r;
+//			do
+//				r1 = uniqp(r1);
+//			while (r1 != R && r1->prog->as == ANOP);
+//			if(r1 == R)
+//				continue;
+//			p1 = r1->prog;
+//			if(p1->to.type != D_REG)
+//				continue;
+//			if(p1->to.reg != p->reg)
+//			if(!(p1->as == AMOVW && p1->from.type == D_REG && p1->from.reg == p->reg))
+//				continue;
+//
+//			switch(p1->as) {
+//			default:
+//				continue;
+//			case AMOVW:
+//				if(p1->from.type != D_REG)
+//					continue;
+//			case AAND:
+//			case AEOR:
+//			case AORR:
+//			case ABIC:
+//			case AMVN:
+//			case ASUB:
+//			case ARSB:
+//			case AADD:
+//			case AADC:
+//			case ASBC:
+//			case ARSC:
+//				break;
+//			}
+//			p1->scond |= C_SBIT;
+//			r2->prog->as = t;
+//			excise(r);
+//			continue;
+//		}
+//	}
 
 	predicate();
 }
@@ -331,7 +333,6 @@ subprop(Reg *r0)
 		case ABL:
 			return 0;
 
-		case ACMP:
 		case ACMN:
 		case AADD:
 		case ASUB:
@@ -346,8 +347,6 @@ subprop(Reg *r0)
 		case ADIV:
 		case ADIVU:
 
-		case ACMPF:
-		case ACMPD:
 		case AADDD:
 		case AADDF:
 		case ASUBD:
@@ -648,6 +647,7 @@ shiftprop(Reg *r)
 				print("\t=>%P", p1);
 		}
 	case ABIC:
+	case ATST:
 	case ACMP:
 	case ACMN:
 		if(p1->reg == n)
@@ -922,8 +922,7 @@ copyu(Prog *p, Adr *v, Adr *s)
 	switch(p->as) {
 
 	default:
-		if(debug['P'])
-			print(" (?)");
+		print("copyu: cant find %A\n", p->as);
 		return 2;
 
 	case AMOVM:
@@ -1028,6 +1027,7 @@ copyu(Prog *p, Adr *v, Adr *s)
 
 	case ACMPF:
 	case ACMPD:
+	case ATST:
 	case ACMP:
 	case ACMN:
 	case ACASE:
@@ -1138,6 +1138,7 @@ a2type(Prog *p)
 
 	switch(p->as) {
 
+	case ATST:
 	case ACMP:
 	case ACMN:
 
@@ -1369,9 +1370,9 @@ int
 modifiescpsr(Prog *p)
 {
 	switch(p->as) {
-	case ATST:
 	case ATEQ:
 	case ACMN:
+	case ATST:
 	case ACMP:
 	case AMULU:
 	case ADIVU:

src/cmd/5g/reg.c

@@ -137,7 +137,8 @@ regopt(Prog *firstp)
 	uint32 vreg;
 	Bits bit;
 
-return; // disabled for the moment
+return;
+
 	if(first == 0) {
 		fmtinstall('Q', Qconv);
 	}
@@ -479,7 +480,7 @@ brk:
 	 * peep-hole on basic block
 	 */
 	if(!debug['R'] || debug['P']) {
-//		peep();
+		peep();
 	}
 
 	/*

src/cmd/5l/asm.c

@@ -793,7 +793,8 @@ if(debug['G']) print("%ux: %s: arm %d %d %d\n", (uint32)(p->pc), p->from.sym->na
 			rt = 0;
 		if(p->as == AMOVW || p->as == AMVN)
 			r = 0;
-		else if(r == NREG)
+		else
+		if(r == NREG)
 			r = rt;
 		o1 |= rf | (r<<16) | (rt<<12);
 		break;
@@ -1558,6 +1559,12 @@ if(debug['G']) print("%ux: %s: arm %d %d %d\n", (uint32)(p->pc), p->from.sym->na
 		o1 |= (p->from.reg<<16);
 		o1 |= (p->to.reg<<12);
 		break;
+
+	case 90:	/* tst reg  */
+		o1 = oprrr(AMOVW, p->scond);
+		o1 |= p->from.reg | (p->from.reg<<12);
+		o1 |= 1 << 20;	// SBIT
+		break;
 	}
 	
 	out[0] = o1;

src/cmd/5l/optab.c

@@ -64,7 +64,7 @@ Optab	optab[] =
 	{ AB,		C_NONE,	C_NONE,	C_ROREG,	 6, 4, 0,	LPOOL },
 	{ ABL,		C_NONE,	C_NONE,	C_ROREG,	 7, 8, 0 },
 	{ ABX,		C_NONE,	C_NONE,	C_ROREG,	 75, 12, 0 },
-	{ ABXRET,		C_NONE,	C_NONE,	C_ROREG,	 76, 4, 0 },
+	{ ABXRET,	C_NONE,	C_NONE,	C_ROREG,	 76, 4, 0 },
 
 	{ ASLL,		C_RCON,	C_REG,	C_REG,		 8, 4, 0 },
 	{ ASLL,		C_RCON,	C_NONE,	C_REG,		 8, 4, 0 },
@@ -251,5 +251,7 @@ Optab	optab[] =
 	{ AMOVW,	C_REG,	C_NONE,	C_FREG,		88, 4, 0 },
 	{ AMOVW,	C_FREG,	C_NONE,	C_REG,		89, 4, 0 },
 
+	{ ATST,		C_REG,	C_NONE,	C_NONE,		90, 4, 0 },
+
 	{ AXXX,		C_NONE,	C_NONE,	C_NONE,		 0, 4, 0 },
 };

src/cmd/5l/span.c

@@ -962,7 +962,6 @@ buildop(void)
 			oprange[ABIC] = oprange[r];
 			break;
 		case ACMP:
-			oprange[ATST] = oprange[r];
 			oprange[ATEQ] = oprange[r];
 			oprange[ACMN] = oprange[r];
 			break;
@@ -1055,6 +1054,7 @@ buildop(void)
 
 		case ALDREX:
 		case ASTREX:
+		case ATST:
 			break;
 		}
 	}