cmd/internal/obj/loong64: remove the incorrect unsigned instructions

The loong64 ISA does not support the 32-bit unsigned arithmetic
instructions ADDU, SUBU and MULU.

Change-Id: Ifa67de9c59aa12d08844189ed23e6daad0cc11ea
Reviewed-on: https://go-review.googlesource.com/c/go/+/722760
Reviewed-by: abner chenc <chenguoqi@loongson.cn>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>

src/cmd/asm/internal/asm/testdata/loong64enc1.s

@@ -199,8 +199,6 @@ lable2:
 	MOVHU	R4, 1(R5)		// a4044029
 	MOVHU	y+8(FP), R4		// 6440402a
 	MOVHU	1(R5), R4		// a404402a
-	MULU	R4, R5	   		// a5101c00
-	MULU	R4, R5, R6		// a6101c00
 	MULH	R4, R5	   		// a5901c00
 	MULH	R4, R5, R6	   	// a6901c00
 	MULHU	R4, R5			// a5101d00

src/cmd/asm/internal/asm/testdata/loong64enc2.s

@@ -41,10 +41,6 @@ TEXT asmtest(SB),DUPOK|NOSPLIT,$0
 	SGTU	$4096, R4, R5		// 3e00001485f81200
 	SGTU	$65536, R4		// 1e02001484f81200
 	SGTU	$4096, R4		// 3e00001484f81200
-	ADDU	$65536, R4, R5		// 1e02001485781000
-	ADDU	$4096, R4, R5		// 3e00001485781000
-	ADDU	$65536, R4		// 1e02001484781000
-	ADDU	$4096, R4		// 3e00001484781000
 	ADDVU	$65536, R4, R5		// 1e02001485f81000
 	ADDVU	$4096, R4, R5		// 3e00001485f81000
 	ADDVU	$65536, R4		// 1e02001484f81000

src/cmd/asm/internal/asm/testdata/loong64enc3.s

@@ -111,10 +111,6 @@ TEXT asmtest(SB),DUPOK|NOSPLIT,$0
 	SGTU	$74565, R4, R5 			// 5e020014de178d0385f81200
 	SGTU	$4097, R4 			// 3e000014de07800384f81200
 	SGTU	$4097, R4, R5 			// 3e000014de07800385f81200
-	ADDU	$74565, R4 			// 5e020014de178d0384781000
-	ADDU	$74565, R4, R5 			// 5e020014de178d0385781000
-	ADDU	$4097, R4 			// 3e000014de07800384781000
-	ADDU	$4097, R4, R5 			// 3e000014de07800385781000
 	ADDVU	$4097, R4			// 3e000014de07800384f81000
 	ADDVU	$4097, R4, R5 			// 3e000014de07800385f81000
 	ADDVU	$74565, R4			// 5e020014de178d0384f81000

src/cmd/internal/obj/loong64/a.out.go

@@ -429,7 +429,6 @@ const (
 	AADD
 	AADDD
 	AADDF
-	AADDU
 
 	AADDW
 	AAND
@@ -495,7 +494,6 @@ const (
 	AMUL
 	AMULD
 	AMULF
-	AMULU
 	AMULH
 	AMULHU
 	AMULW
@@ -531,7 +529,6 @@ const (
 	ASUBD
 	ASUBF
 
-	ASUBU
 	ASUBW
 	ADBAR
 	ASYSCALL

src/cmd/internal/obj/loong64/anames.go

@@ -10,7 +10,6 @@ var Anames = []string{
 	"ADD",
 	"ADDD",
 	"ADDF",
-	"ADDU",
 	"ADDW",
 	"AND",
 	"BEQ",
@@ -63,7 +62,6 @@ var Anames = []string{
 	"MUL",
 	"MULD",
 	"MULF",
-	"MULU",
 	"MULH",
 	"MULHU",
 	"MULW",
@@ -92,7 +90,6 @@ var Anames = []string{
 	"SUB",
 	"SUBD",
 	"SUBF",
-	"SUBU",
 	"SUBW",
 	"DBAR",
 	"SYSCALL",

src/cmd/internal/obj/loong64/asm.go

@@ -1431,7 +1431,6 @@ func buildop(ctxt *obj.Link) {
 			opset(AADDW, r0)
 			opset(ASGT, r0)
 			opset(ASGTU, r0)
-			opset(AADDU, r0)
 
 		case AADDV:
 			opset(AADDVU, r0)
@@ -1514,13 +1513,11 @@ func buildop(ctxt *obj.Link) {
 
 		case ASUB:
 			opset(ASUBW, r0)
-			opset(ASUBU, r0)
 			opset(ANOR, r0)
 			opset(ASUBV, r0)
 			opset(ASUBVU, r0)
 			opset(AMUL, r0)
 			opset(AMULW, r0)
-			opset(AMULU, r0)
 			opset(AMULH, r0)
 			opset(AMULHU, r0)
 			opset(AREM, r0)
@@ -2296,8 +2293,7 @@ func (c *ctxt0) asmout(p *obj.Prog, o *Optab, out []uint32) {
 	o5 := uint32(0)
 	o6 := uint32(0)
 
-	add := AADDU
+	add := AADDVU
-	add = AADDVU
 
 	switch o.type_ {
 	default:
@@ -2428,7 +2424,7 @@ func (c *ctxt0) asmout(p *obj.Prog, o *Optab, out []uint32) {
 		v := c.regoff(&p.From)
 		a := AOR
 		if v < 0 {
-			a = AADDU
+			a = AADD
 		}
 		o1 = OP_12IRR(c.opirr(a), uint32(v), uint32(0), uint32(REGTMP))
 		r := int(p.Reg)
@@ -2687,7 +2683,7 @@ func (c *ctxt0) asmout(p *obj.Prog, o *Optab, out []uint32) {
 
 	case 34: // mov $con,fr
 		v := c.regoff(&p.From)
-		a := AADDU
+		a := AADD
 		if v > 0 {
 			a = AOR
 		}
@@ -3317,8 +3313,6 @@ func (c *ctxt0) oprrr(a obj.As) uint32 {
 	switch a {
 	case AADD, AADDW:
 		return 0x20 << 15
-	case AADDU:
-		return 0x20 << 15
 	case ASGT:
 		return 0x24 << 15 // SLT
 	case ASGTU:
@@ -3337,9 +3331,7 @@ func (c *ctxt0) oprrr(a obj.As) uint32 {
 		return 0x2c << 15 // orn
 	case AANDN:
 		return 0x2d << 15 // andn
-	case ASUB, ASUBW:
+	case ASUB, ASUBW, ANEGW:
-		return 0x22 << 15
-	case ASUBU, ANEGW:
 		return 0x22 << 15
 	case ANOR:
 		return 0x28 << 15
@@ -3370,8 +3362,6 @@ func (c *ctxt0) oprrr(a obj.As) uint32 {
 
 	case AMUL, AMULW:
 		return 0x38 << 15 // mul.w
-	case AMULU:
-		return 0x38 << 15 // mul.w
 	case AMULH:
 		return 0x39 << 15 // mulh.w
 	case AMULHU:
@@ -4684,7 +4674,7 @@ func (c *ctxt0) opir(a obj.As) uint32 {
 
 func (c *ctxt0) opirr(a obj.As) uint32 {
 	switch a {
-	case AADD, AADDW, AADDU:
+	case AADD, AADDW:
 		return 0x00a << 22
 	case ASGT:
 		return 0x008 << 22

src/cmd/internal/obj/loong64/obj.go

@@ -64,12 +64,6 @@ func progedit(ctxt *obj.Link, p *obj.Prog, newprog obj.ProgAlloc) {
 			p.As = AADD
 		}
 
-	case ASUBU:
-		if p.From.Type == obj.TYPE_CONST {
-			p.From.Offset = -p.From.Offset
-			p.As = AADDU
-		}
-
 	case ASUBV:
 		if p.From.Type == obj.TYPE_CONST {
 			p.From.Offset = -p.From.Offset
@@ -453,7 +447,6 @@ func preprocess(ctxt *obj.Link, cursym *obj.LSym, newprog obj.ProgAlloc) {
 			q.Link = q1
 
 		case AADD,
-			AADDU,
 			AADDV,
 			AADDVU:
 			if p.To.Type == obj.TYPE_REG && p.To.Reg == REGSP && p.From.Type == obj.TYPE_CONST {