cmd/compile, cmd/internal/obj: ignore AUSEFIELD

When using GOEXPERIMENT=fieldtrack, we can see AUSEFIELD instructions.
We generally want to ignore them.

No tests because as far as I can tell there are no tests for
GOEXPERIMENT=fieldtrack.

Change-Id: Iee26f25592158e5db691a36cf8d77fc54d051314
Reviewed-on: https://go-review.googlesource.com/17610Reviewed-by: David Symonds <dsymonds@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/cmd/compile/internal/arm/peep.go

@@ -1365,7 +1365,8 @@ func copyu(p *obj.Prog, v *obj.Addr, s *obj.Addr) int {
 	case obj.APCDATA,
 		obj.AFUNCDATA,
 		obj.AVARDEF,
-		obj.AVARKILL:
+		obj.AVARKILL,
+		obj.AUSEFIELD:
 		return 0
 	}
 }

src/cmd/compile/internal/arm64/peep.go

@@ -710,7 +710,8 @@ func copyu(p *obj.Prog, v *obj.Addr, s *obj.Addr) int {
 		obj.APCDATA,
 		obj.AFUNCDATA,
 		obj.AVARDEF,
-		obj.AVARKILL:
+		obj.AVARKILL,
+		obj.AUSEFIELD:
 		return 0
 	}
 }

src/cmd/compile/internal/mips64/peep.go

@@ -687,7 +687,8 @@ func copyu(p *obj.Prog, v *obj.Addr, s *obj.Addr) int {
 	case obj.APCDATA,
 		obj.AFUNCDATA,
 		obj.AVARDEF,
-		obj.AVARKILL:
+		obj.AVARKILL,
+		obj.AUSEFIELD:
 		return 0
 	}
 }

src/cmd/compile/internal/ppc64/peep.go

@@ -952,7 +952,8 @@ func copyu(p *obj.Prog, v *obj.Addr, s *obj.Addr) int {
 	case obj.APCDATA,
 		obj.AFUNCDATA,
 		obj.AVARDEF,
-		obj.AVARKILL:
+		obj.AVARKILL,
+		obj.AUSEFIELD:
 		return 0
 	}
 }

src/cmd/internal/obj/arm/asm5.go

@@ -614,7 +614,7 @@ func span5(ctxt *obj.Link, cursym *obj.LSym) {
 			}
 		}
 
-		if m == 0 && (p.As != obj.AFUNCDATA && p.As != obj.APCDATA && p.As != ADATABUNDLEEND && p.As != obj.ANOP) {
+		if m == 0 && (p.As != obj.AFUNCDATA && p.As != obj.APCDATA && p.As != ADATABUNDLEEND && p.As != obj.ANOP && p.As != obj.AUSEFIELD) {
 			ctxt.Diag("zero-width instruction\n%v", p)
 			continue
 		}
@@ -710,7 +710,7 @@ func span5(ctxt *obj.Link, cursym *obj.LSym) {
 			if m/4 > len(out) {
 				ctxt.Diag("instruction size too large: %d > %d", m/4, len(out))
 			}
-			if m == 0 && (p.As != obj.AFUNCDATA && p.As != obj.APCDATA && p.As != ADATABUNDLEEND && p.As != obj.ANOP) {
+			if m == 0 && (p.As != obj.AFUNCDATA && p.As != obj.APCDATA && p.As != ADATABUNDLEEND && p.As != obj.ANOP && p.As != obj.AUSEFIELD) {
 				if p.As == obj.ATEXT {
 					ctxt.Autosize = int32(p.To.Offset + 4)
 					continue

src/cmd/internal/obj/arm64/asm7.go

@@ -550,7 +550,7 @@ func span7(ctxt *obj.Link, cursym *obj.LSym) {
 		o = oplook(ctxt, p)
 		m = int(o.size)
 		if m == 0 {
-			if p.As != obj.ANOP && p.As != obj.AFUNCDATA && p.As != obj.APCDATA {
+			if p.As != obj.ANOP && p.As != obj.AFUNCDATA && p.As != obj.APCDATA && p.As != obj.AUSEFIELD {
 				ctxt.Diag("zero-width instruction\n%v", p)
 			}
 			continue
@@ -618,7 +618,7 @@ func span7(ctxt *obj.Link, cursym *obj.LSym) {
 			m = int(o.size)
 
 			if m == 0 {
-				if p.As != obj.ANOP && p.As != obj.AFUNCDATA && p.As != obj.APCDATA {
+				if p.As != obj.ANOP && p.As != obj.AFUNCDATA && p.As != obj.APCDATA && p.As != obj.AUSEFIELD {
 					ctxt.Diag("zero-width instruction\n%v", p)
 				}
 				continue

src/cmd/internal/obj/mips/asm0.go

@@ -342,7 +342,7 @@ func span0(ctxt *obj.Link, cursym *obj.LSym) {
 		o = oplook(ctxt, p)
 		m = int(o.size)
 		if m == 0 {
-			if p.As != obj.ANOP && p.As != obj.AFUNCDATA && p.As != obj.APCDATA {
+			if p.As != obj.ANOP && p.As != obj.AFUNCDATA && p.As != obj.APCDATA && p.As != obj.AUSEFIELD {
 				ctxt.Diag("zero-width instruction\n%v", p)
 			}
 			continue
@@ -401,7 +401,7 @@ func span0(ctxt *obj.Link, cursym *obj.LSym) {
 
 			m = int(o.size)
 			if m == 0 {
-				if p.As != obj.ANOP && p.As != obj.AFUNCDATA && p.As != obj.APCDATA {
+				if p.As != obj.ANOP && p.As != obj.AFUNCDATA && p.As != obj.APCDATA && p.As != obj.AUSEFIELD {
 					ctxt.Diag("zero-width instruction\n%v", p)
 				}
 				continue

src/cmd/internal/obj/ppc64/asm9.go

@@ -435,7 +435,7 @@ func span9(ctxt *obj.Link, cursym *obj.LSym) {
 		o = oplook(ctxt, p)
 		m = int(o.size)
 		if m == 0 {
-			if p.As != obj.ANOP && p.As != obj.AFUNCDATA && p.As != obj.APCDATA {
+			if p.As != obj.ANOP && p.As != obj.AFUNCDATA && p.As != obj.APCDATA && p.As != obj.AUSEFIELD {
 				ctxt.Diag("zero-width instruction\n%v", p)
 			}
 			continue
@@ -492,7 +492,7 @@ func span9(ctxt *obj.Link, cursym *obj.LSym) {
 
 			m = int(o.size)
 			if m == 0 {
-				if p.As != obj.ANOP && p.As != obj.AFUNCDATA && p.As != obj.APCDATA {
+				if p.As != obj.ANOP && p.As != obj.AFUNCDATA && p.As != obj.APCDATA && p.As != obj.AUSEFIELD {
 					ctxt.Diag("zero-width instruction\n%v", p)
 				}
 				continue