cmd/objdump: add s390x GNU disasm support

This CL provides vendor support for s390x disassembler gnu syntax.
go get golang.org/x/arch@master
go mod tidy
go mod vendor

For #15255

Change-Id: Ia75fa515e7ea7d56913a28147c65650a7ab3062c
Reviewed-on: https://go-review.googlesource.com/c/go/+/581015
Reviewed-by: Cherry Mui <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>
Reviewed-by: Vishwanatha HD <[email protected]>
Run-TryBot: Cherry Mui <[email protected]>
Auto-Submit: Cherry Mui <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>
Reviewed-by: Dmitri Shuralyov <[email protected]>
Reviewed-by: Bill O'Farrell <[email protected]>

src/cmd/go.mod

@@ -4,7 +4,7 @@ go 1.24
 
 require (
 	github.com/google/pprof v0.0.0-20240722153945-304e4f0156b8
-	golang.org/x/arch v0.8.1-0.20240716161256-b863392466ea
+	golang.org/x/arch v0.9.1-0.20240807172201-9d90945922a7
 	golang.org/x/build v0.0.0-20240722200705-b9910f320300
 	golang.org/x/mod v0.20.0
 	golang.org/x/sync v0.8.0

src/cmd/go.sum

@@ -6,8 +6,8 @@ github.com/ianlancetaylor/demangle v0.0.0-20240312041847-bd984b5ce465 h1:KwWnWVW
 github.com/ianlancetaylor/demangle v0.0.0-20240312041847-bd984b5ce465/go.mod h1:gx7rwoVhcfuVKG5uya9Hs3Sxj7EIvldVofAWIUtGouw=
 github.com/yuin/goldmark v1.6.0 h1:boZcn2GTjpsynOsC0iJHnBWa4Bi0qzfJjthwauItG68=
 github.com/yuin/goldmark v1.6.0/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
-golang.org/x/arch v0.8.1-0.20240716161256-b863392466ea h1:+dKVGZM+cuxx3fooVKLDxZIPzKR1HYO1Xkd12Je4Z9k=
-golang.org/x/arch v0.8.1-0.20240716161256-b863392466ea/go.mod h1:FEVrYAQjsQXMVJ1nsMoVVXPZg6p2JE2mx8psSWTDQys=
+golang.org/x/arch v0.9.1-0.20240807172201-9d90945922a7 h1:4+03DsxQb03qtr7e32FA8tiq18ytCUClXaXxQBDRGbs=
+golang.org/x/arch v0.9.1-0.20240807172201-9d90945922a7/go.mod h1:FEVrYAQjsQXMVJ1nsMoVVXPZg6p2JE2mx8psSWTDQys=
 golang.org/x/build v0.0.0-20240722200705-b9910f320300 h1:2Cqg4LnvfD2ZpG8+6KbyYUkweWhNS3SgfcN/eeVseJ0=
 golang.org/x/build v0.0.0-20240722200705-b9910f320300/go.mod h1:YsGhg4JUVUWLzdqU2wCrtpRrOveOql6w56FLDHq/CJ4=
 golang.org/x/mod v0.20.0 h1:utOm6MM3R3dnawAiJgn0y+xvuYRsm1RKM/4giyfDgV0=

src/cmd/internal/objfile/disasm.go

@@ -24,6 +24,7 @@ import (
 	"golang.org/x/arch/arm/armasm"
 	"golang.org/x/arch/arm64/arm64asm"
 	"golang.org/x/arch/ppc64/ppc64asm"
+	"golang.org/x/arch/s390x/s390xasm"
 	"golang.org/x/arch/x86/x86asm"
 )
 
@@ -383,13 +384,31 @@ func disasm_ppc64(code []byte, pc uint64, lookup lookupFunc, byteOrder binary.By
 	return text, size
 }
 
+func disasm_s390x(code []byte, pc uint64, lookup lookupFunc, _ binary.ByteOrder, gnuAsm bool) (string, int) {
+	inst, err := s390xasm.Decode(code)
+	var text string
+	size := inst.Len
+	if err != nil || size == 0 || inst.Op == 0 {
+		size = 2
+		text = "?"
+	} else {
+		if gnuAsm {
+			text = fmt.Sprintf("%s", s390xasm.GNUSyntax(inst, pc))
+		} else {
+			text = fmt.Sprintf("%s", "Go/plan9 syntax unsupported..!!")
+		}
+	}
+	return text, size
+}
+
 var disasms = map[string]disasmFunc{
 	"386":     disasm_386,
 	"amd64":   disasm_amd64,
 	"arm":     disasm_arm,
 	"arm64":   disasm_arm64,
 	"ppc64":   disasm_ppc64,
 	"ppc64le": disasm_ppc64,
+	"s390x":   disasm_s390x,
 }
 
 var byteOrders = map[string]binary.ByteOrder{

src/cmd/objdump/objdump_test.go

@@ -104,6 +104,12 @@ var ppcGnuNeed = []string{
 	"beq",
 }
 
+var s390xGnuNeed = []string{
+	"brasl",
+	"j",
+	"clije",
+}
+
 func mustHaveDisasm(t *testing.T) {
 	switch runtime.GOARCH {
 	case "loong64":
@@ -112,8 +118,6 @@ func mustHaveDisasm(t *testing.T) {
 		t.Skipf("skipping on %s, issue 12559", runtime.GOARCH)
 	case "riscv64":
 		t.Skipf("skipping on %s, issue 36738", runtime.GOARCH)
-	case "s390x":
-		t.Skipf("skipping on %s, issue 15255", runtime.GOARCH)
 	}
 }
 
@@ -202,6 +206,8 @@ func testDisasm(t *testing.T, srcfname string, printCode bool, printGnuAsm bool,
 			need = append(need, armGnuNeed...)
 		case "ppc64", "ppc64le":
 			need = append(need, ppcGnuNeed...)
+		case "s390x":
+			need = append(need, s390xGnuNeed...)
 		}
 	}
 	args = []string{