Update vendor (#1297)

vendor/golang.org/x/sys/cpu/cpu_s390x.go

@@ -8,10 +8,10 @@ const cacheLineSize = 256
 
 func initOptions() {
 	options = []option{
-		{Name: "zarch", Feature: &S390X.HasZARCH},
-		{Name: "stfle", Feature: &S390X.HasSTFLE},
-		{Name: "ldisp", Feature: &S390X.HasLDISP},
-		{Name: "eimm", Feature: &S390X.HasEIMM},
+		{Name: "zarch", Feature: &S390X.HasZARCH, Required: true},
+		{Name: "stfle", Feature: &S390X.HasSTFLE, Required: true},
+		{Name: "ldisp", Feature: &S390X.HasLDISP, Required: true},
+		{Name: "eimm", Feature: &S390X.HasEIMM, Required: true},
 		{Name: "dfp", Feature: &S390X.HasDFP},
 		{Name: "etf3eh", Feature: &S390X.HasETF3EH},
 		{Name: "msa", Feature: &S390X.HasMSA},
@@ -28,3 +28,145 @@ func initOptions() {
 		{Name: "vxe", Feature: &S390X.HasVXE},
 	}
 }
+
+// bitIsSet reports whether the bit at index is set. The bit index
+// is in big endian order, so bit index 0 is the leftmost bit.
+func bitIsSet(bits []uint64, index uint) bool {
+	return bits[index/64]&((1<<63)>>(index%64)) != 0
+}
+
+// facility is a bit index for the named facility.
+type facility uint8
+
+const (
+	// mandatory facilities
+	zarch  facility = 1  // z architecture mode is active
+	stflef facility = 7  // store-facility-list-extended
+	ldisp  facility = 18 // long-displacement
+	eimm   facility = 21 // extended-immediate
+
+	// miscellaneous facilities
+	dfp    facility = 42 // decimal-floating-point
+	etf3eh facility = 30 // extended-translation 3 enhancement
+
+	// cryptography facilities
+	msa  facility = 17  // message-security-assist
+	msa3 facility = 76  // message-security-assist extension 3
+	msa4 facility = 77  // message-security-assist extension 4
+	msa5 facility = 57  // message-security-assist extension 5
+	msa8 facility = 146 // message-security-assist extension 8
+	msa9 facility = 155 // message-security-assist extension 9
+
+	// vector facilities
+	vx   facility = 129 // vector facility
+	vxe  facility = 135 // vector-enhancements 1
+	vxe2 facility = 148 // vector-enhancements 2
+)
+
+// facilityList contains the result of an STFLE call.
+// Bits are numbered in big endian order so the
+// leftmost bit (the MSB) is at index 0.
+type facilityList struct {
+	bits [4]uint64
+}
+
+// Has reports whether the given facilities are present.
+func (s *facilityList) Has(fs ...facility) bool {
+	if len(fs) == 0 {
+		panic("no facility bits provided")
+	}
+	for _, f := range fs {
+		if !bitIsSet(s.bits[:], uint(f)) {
+			return false
+		}
+	}
+	return true
+}
+
+// function is the code for the named cryptographic function.
+type function uint8
+
+const (
+	// KM{,A,C,CTR} function codes
+	aes128 function = 18 // AES-128
+	aes192 function = 19 // AES-192
+	aes256 function = 20 // AES-256
+
+	// K{I,L}MD function codes
+	sha1     function = 1  // SHA-1
+	sha256   function = 2  // SHA-256
+	sha512   function = 3  // SHA-512
+	sha3_224 function = 32 // SHA3-224
+	sha3_256 function = 33 // SHA3-256
+	sha3_384 function = 34 // SHA3-384
+	sha3_512 function = 35 // SHA3-512
+	shake128 function = 36 // SHAKE-128
+	shake256 function = 37 // SHAKE-256
+
+	// KLMD function codes
+	ghash function = 65 // GHASH
+)
+
+// queryResult contains the result of a Query function
+// call. Bits are numbered in big endian order so the
+// leftmost bit (the MSB) is at index 0.
+type queryResult struct {
+	bits [2]uint64
+}
+
+// Has reports whether the given functions are present.
+func (q *queryResult) Has(fns ...function) bool {
+	if len(fns) == 0 {
+		panic("no function codes provided")
+	}
+	for _, f := range fns {
+		if !bitIsSet(q.bits[:], uint(f)) {
+			return false
+		}
+	}
+	return true
+}
+
+func doinit() {
+	initS390Xbase()
+
+	// We need implementations of stfle, km and so on
+	// to detect cryptographic features.
+	if !haveAsmFunctions() {
+		return
+	}
+
+	// optional cryptographic functions
+	if S390X.HasMSA {
+		aes := []function{aes128, aes192, aes256}
+
+		// cipher message
+		km, kmc := kmQuery(), kmcQuery()
+		S390X.HasAES = km.Has(aes...)
+		S390X.HasAESCBC = kmc.Has(aes...)
+		if S390X.HasSTFLE {
+			facilities := stfle()
+			if facilities.Has(msa4) {
+				kmctr := kmctrQuery()
+				S390X.HasAESCTR = kmctr.Has(aes...)
+			}
+			if facilities.Has(msa8) {
+				kma := kmaQuery()
+				S390X.HasAESGCM = kma.Has(aes...)
+			}
+		}
+
+		// compute message digest
+		kimd := kimdQuery() // intermediate (no padding)
+		klmd := klmdQuery() // last (padding)
+		S390X.HasSHA1 = kimd.Has(sha1) && klmd.Has(sha1)
+		S390X.HasSHA256 = kimd.Has(sha256) && klmd.Has(sha256)
+		S390X.HasSHA512 = kimd.Has(sha512) && klmd.Has(sha512)
+		S390X.HasGHASH = kimd.Has(ghash) // KLMD-GHASH does not exist
+		sha3 := []function{
+			sha3_224, sha3_256, sha3_384, sha3_512,
+			shake128, shake256,
+		}
+		S390X.HasSHA3 = kimd.Has(sha3...) && klmd.Has(sha3...)
+	}
+}