interop: return struct pointers where needed

`Transaction`, `Block` and `Contract` are represented as
`Array`s in VM, so we must return pointers.

Revert a1f98f92.

pkg/compiler/codegen.go

@@ -1392,10 +1392,7 @@ func (c *codegen) convertSyscall(expr *ast.CallExpr, api, name string) {
 		c.prog.Err = fmt.Errorf("unknown VM syscall api: %s.%s", api, name)
 		return
 	}
-	emit.Syscall(c.prog.BinWriter, syscall.API)
-	if syscall.ConvertResultToStruct {
-		c.emitConvert(stackitem.StructT)
-	}
+	emit.Syscall(c.prog.BinWriter, syscall)
 
 	// This NOP instruction is basically not needed, but if we do, we have a
 	// one to one matching avm file with neo-python which is very nice for debugging.

pkg/compiler/syscall.go

@@ -2,91 +2,85 @@ package compiler
 
 import "github.com/nspcc-dev/neo-go/pkg/core/interop/interopnames"
 
-// Syscall represents NEO or System syscall API with flag for proper AVM generation
-type Syscall struct {
-	API                   string
-	ConvertResultToStruct bool
-}
-
 // All lists are sorted, keep 'em this way, please.
-var syscalls = map[string]map[string]Syscall{
+var syscalls = map[string]map[string]string{
 	"binary": {
-		"Base58Decode": {interopnames.SystemBinaryBase58Decode, false},
-		"Base58Encode": {interopnames.SystemBinaryBase58Encode, false},
-		"Base64Decode": {interopnames.SystemBinaryBase64Decode, false},
-		"Base64Encode": {interopnames.SystemBinaryBase64Encode, false},
-		"Deserialize":  {interopnames.SystemBinaryDeserialize, false},
-		"Serialize":    {interopnames.SystemBinarySerialize, false},
+		"Base58Decode": interopnames.SystemBinaryBase58Decode,
+		"Base58Encode": interopnames.SystemBinaryBase58Encode,
+		"Base64Decode": interopnames.SystemBinaryBase64Decode,
+		"Base64Encode": interopnames.SystemBinaryBase64Encode,
+		"Deserialize":  interopnames.SystemBinaryDeserialize,
+		"Serialize":    interopnames.SystemBinarySerialize,
 	},
 	"blockchain": {
-		"GetBlock":                {interopnames.SystemBlockchainGetBlock, true},
-		"GetContract":             {interopnames.SystemBlockchainGetContract, true},
-		"GetHeight":               {interopnames.SystemBlockchainGetHeight, false},
-		"GetTransaction":          {interopnames.SystemBlockchainGetTransaction, true},
-		"GetTransactionFromBlock": {interopnames.SystemBlockchainGetTransactionFromBlock, false},
-		"GetTransactionHeight":    {interopnames.SystemBlockchainGetTransactionHeight, false},
+		"GetBlock":                interopnames.SystemBlockchainGetBlock,
+		"GetContract":             interopnames.SystemBlockchainGetContract,
+		"GetHeight":               interopnames.SystemBlockchainGetHeight,
+		"GetTransaction":          interopnames.SystemBlockchainGetTransaction,
+		"GetTransactionFromBlock": interopnames.SystemBlockchainGetTransactionFromBlock,
+		"GetTransactionHeight":    interopnames.SystemBlockchainGetTransactionHeight,
 	},
 	"contract": {
-		"Create":                {interopnames.SystemContractCreate, true},
-		"CreateStandardAccount": {interopnames.SystemContractCreateStandardAccount, false},
-		"Destroy":               {interopnames.SystemContractDestroy, false},
-		"IsStandard":            {interopnames.SystemContractIsStandard, false},
-		"GetCallFlags":          {interopnames.SystemContractGetCallFlags, false},
-		"Update":                {interopnames.SystemContractUpdate, false},
+		"Create":                interopnames.SystemContractCreate,
+		"CreateStandardAccount": interopnames.SystemContractCreateStandardAccount,
+		"Destroy":               interopnames.SystemContractDestroy,
+		"IsStandard":            interopnames.SystemContractIsStandard,
+		"GetCallFlags":          interopnames.SystemContractGetCallFlags,
+		"Update":                interopnames.SystemContractUpdate,
 	},
 	"crypto": {
-		"ECDsaSecp256k1Verify":        {interopnames.NeoCryptoVerifyWithECDsaSecp256k1, false},
-		"ECDSASecp256k1CheckMultisig": {interopnames.NeoCryptoCheckMultisigWithECDsaSecp256k1, false},
-		"ECDsaSecp256r1Verify":        {interopnames.NeoCryptoVerifyWithECDsaSecp256r1, false},
-		"ECDSASecp256r1CheckMultisig": {interopnames.NeoCryptoCheckMultisigWithECDsaSecp256r1, false},
-		"RIPEMD160":                   {interopnames.NeoCryptoRIPEMD160, false},
-		"SHA256":                      {interopnames.NeoCryptoSHA256, false},
+		"ECDsaSecp256k1Verify":        interopnames.NeoCryptoVerifyWithECDsaSecp256k1,
+		"ECDSASecp256k1CheckMultisig": interopnames.NeoCryptoCheckMultisigWithECDsaSecp256k1,
+		"ECDsaSecp256r1Verify":        interopnames.NeoCryptoVerifyWithECDsaSecp256r1,
+		"ECDSASecp256r1CheckMultisig": interopnames.NeoCryptoCheckMultisigWithECDsaSecp256r1,
+		"RIPEMD160":                   interopnames.NeoCryptoRIPEMD160,
+		"SHA256":                      interopnames.NeoCryptoSHA256,
 	},
 	"enumerator": {
-		"Concat": {interopnames.SystemEnumeratorConcat, false},
-		"Create": {interopnames.SystemEnumeratorCreate, false},
-		"Next":   {interopnames.SystemEnumeratorNext, false},
-		"Value":  {interopnames.SystemEnumeratorValue, false},
+		"Concat": interopnames.SystemEnumeratorConcat,
+		"Create": interopnames.SystemEnumeratorCreate,
+		"Next":   interopnames.SystemEnumeratorNext,
+		"Value":  interopnames.SystemEnumeratorValue,
 	},
 	"engine": {
-		"AppCall": {interopnames.SystemContractCall, false},
+		"AppCall": interopnames.SystemContractCall,
 	},
 	"iterator": {
-		"Concat": {interopnames.SystemIteratorConcat, false},
-		"Create": {interopnames.SystemIteratorCreate, false},
-		"Key":    {interopnames.SystemIteratorKey, false},
-		"Keys":   {interopnames.SystemIteratorKeys, false},
-		"Next":   {interopnames.SystemEnumeratorNext, false},
-		"Value":  {interopnames.SystemEnumeratorValue, false},
-		"Values": {interopnames.SystemIteratorValues, false},
+		"Concat": interopnames.SystemIteratorConcat,
+		"Create": interopnames.SystemIteratorCreate,
+		"Key":    interopnames.SystemIteratorKey,
+		"Keys":   interopnames.SystemIteratorKeys,
+		"Next":   interopnames.SystemEnumeratorNext,
+		"Value":  interopnames.SystemEnumeratorValue,
+		"Values": interopnames.SystemIteratorValues,
 	},
 	"json": {
-		"Deserialize": {interopnames.SystemJSONDeserialize, false},
-		"Serialize":   {interopnames.SystemJSONSerialize, false},
+		"Deserialize": interopnames.SystemJSONDeserialize,
+		"Serialize":   interopnames.SystemJSONSerialize,
 	},
 	"runtime": {
-		"GasLeft":                {interopnames.SystemRuntimeGasLeft, false},
-		"GetInvocationCounter":   {interopnames.SystemRuntimeGetInvocationCounter, false},
-		"GetCallingScriptHash":   {interopnames.SystemRuntimeGetCallingScriptHash, false},
-		"GetEntryScriptHash":     {interopnames.SystemRuntimeGetEntryScriptHash, false},
-		"GetExecutingScriptHash": {interopnames.SystemRuntimeGetExecutingScriptHash, false},
-		"GetNotifications":       {interopnames.SystemRuntimeGetNotifications, false},
-		"GetScriptContainer":     {interopnames.SystemRuntimeGetScriptContainer, true},
-		"GetTime":                {interopnames.SystemRuntimeGetTime, false},
-		"GetTrigger":             {interopnames.SystemRuntimeGetTrigger, false},
-		"CheckWitness":           {interopnames.SystemRuntimeCheckWitness, false},
-		"Log":                    {interopnames.SystemRuntimeLog, false},
-		"Notify":                 {interopnames.SystemRuntimeNotify, false},
-		"Platform":               {interopnames.SystemRuntimePlatform, false},
+		"GasLeft":                interopnames.SystemRuntimeGasLeft,
+		"GetInvocationCounter":   interopnames.SystemRuntimeGetInvocationCounter,
+		"GetCallingScriptHash":   interopnames.SystemRuntimeGetCallingScriptHash,
+		"GetEntryScriptHash":     interopnames.SystemRuntimeGetEntryScriptHash,
+		"GetExecutingScriptHash": interopnames.SystemRuntimeGetExecutingScriptHash,
+		"GetNotifications":       interopnames.SystemRuntimeGetNotifications,
+		"GetScriptContainer":     interopnames.SystemRuntimeGetScriptContainer,
+		"GetTime":                interopnames.SystemRuntimeGetTime,
+		"GetTrigger":             interopnames.SystemRuntimeGetTrigger,
+		"CheckWitness":           interopnames.SystemRuntimeCheckWitness,
+		"Log":                    interopnames.SystemRuntimeLog,
+		"Notify":                 interopnames.SystemRuntimeNotify,
+		"Platform":               interopnames.SystemRuntimePlatform,
 	},
 	"storage": {
-		"ConvertContextToReadOnly": {interopnames.SystemStorageAsReadOnly, false},
-		"Delete":                   {interopnames.SystemStorageDelete, false},
-		"Find":                     {interopnames.SystemStorageFind, false},
-		"Get":                      {interopnames.SystemStorageGet, false},
-		"GetContext":               {interopnames.SystemStorageGetContext, false},
-		"GetReadOnlyContext":       {interopnames.SystemStorageGetReadOnlyContext, false},
-		"Put":                      {interopnames.SystemStoragePut, false},
-		"PutEx":                    {interopnames.SystemStoragePutEx, false},
+		"ConvertContextToReadOnly": interopnames.SystemStorageAsReadOnly,
+		"Delete":                   interopnames.SystemStorageDelete,
+		"Find":                     interopnames.SystemStorageFind,
+		"Get":                      interopnames.SystemStorageGet,
+		"GetContext":               interopnames.SystemStorageGetContext,
+		"GetReadOnlyContext":       interopnames.SystemStorageGetReadOnlyContext,
+		"Put":                      interopnames.SystemStoragePut,
+		"PutEx":                    interopnames.SystemStoragePutEx,
 	},
 }

pkg/interop/blockchain/blockchain.go

@@ -70,15 +70,15 @@ func GetHeight() int {
 // GetBlock returns block found by the given hash or index (with the same
 // encoding as for GetHeader). This function uses `System.Blockchain.GetBlock`
 // syscall.
-func GetBlock(heightOrHash interface{}) Block {
-	return Block{}
+func GetBlock(heightOrHash interface{}) *Block {
+	return &Block{}
 }
 
 // GetTransaction returns transaction found by the given hash (256 bit in BE
 // format represented as a slice of 32 bytes). This function uses
 // `System.Blockchain.GetTransaction` syscall.
-func GetTransaction(hash interop.Hash256) Transaction {
-	return Transaction{}
+func GetTransaction(hash interop.Hash256) *Transaction {
+	return &Transaction{}
 }
 
 // GetTransactionFromBlock returns transaction hash (256 bit in BE format
@@ -100,6 +100,6 @@ func GetTransactionHeight(hash interop.Hash256) int {
 // format represented as a slice of 20 bytes). Refer to the `contract` package
 // for details on how to use the returned structure. This function uses
 // `System.Blockchain.GetContract` syscall.
-func GetContract(scriptHash interop.Hash160) contract.Contract {
-	return contract.Contract{}
+func GetContract(scriptHash interop.Hash160) *contract.Contract {
+	return &contract.Contract{}
 }

pkg/interop/contract/contract.go

@@ -21,8 +21,8 @@ type Contract struct {
 //     manifest    contract's manifest (limited in length by 2 KiB)
 // It returns this new created Contract when successful (and fails transaction
 // if not). It uses `System.Contract.Create` syscall.
-func Create(script []byte, manifest []byte) Contract {
-	return Contract{}
+func Create(script []byte, manifest []byte) *Contract {
+	return &Contract{}
 }
 
 // Update updates script and manifest of the calling contract (that is the one that calls Update)

pkg/interop/runtime/engine.go

@@ -9,8 +9,8 @@ import (
 // execution context. It never changes in a single execution, no matter how deep
 // this execution goes. This function uses
 // `System.Runtime.GetScriptContainer` syscall.
-func GetScriptContainer() blockchain.Transaction {
-	return blockchain.Transaction{}
+func GetScriptContainer() *blockchain.Transaction {
+	return &blockchain.Transaction{}
 }
 
 // GetExecutingScriptHash returns script hash (160 bit in BE form represented