core/vm: use common.Hash instead of nil, fix review comments

core/vm/contract.go

@@ -53,7 +53,7 @@ type Contract struct {
 	analysis  bitvec       // Locally cached result of JUMPDEST analysis
 
 	Code     []byte
-	CodeHash *common.Hash
+	CodeHash common.Hash
 	CodeAddr *common.Address
 	Input    []byte
 
@@ -94,15 +94,15 @@ func (c *Contract) validJumpdest(dest *big.Int) bool {
 	}
 	var analysis bitvec
 	// Do we have a contract hash already?
-	if c.CodeHash != nil {
+	if c.CodeHash != emptyCodeHash {
 		var exist bool
 		// Does parent context have the analysis?
-		analysis, exist = c.jumpdests[*c.CodeHash]
+		analysis, exist = c.jumpdests[c.CodeHash]
 		if !exist {
 			// Do the analysis
 			analysis = codeBitmap(c.Code)
 			// Save in parent context
-			c.jumpdests[*c.CodeHash] = analysis
+			c.jumpdests[c.CodeHash] = analysis
 		}
 		return analysis.codeSegment(udest)
 	}
@@ -173,13 +173,13 @@ func (c *Contract) Value() *big.Int {
 // object
 func (c *Contract) SetCallCode(addr *common.Address, hash common.Hash, code []byte) {
 	c.Code = code
-	c.CodeHash = &hash
+	c.CodeHash = hash
 	c.CodeAddr = addr
 }
 
 // SetCodeOptionalHash can be used to provide code, but it's optional to provide hash.
 // In case hash is not provided, the jumpdest analysis will not be saved to the parent context
-func (c *Contract) SetCodeOptionalHash(addr *common.Address, codeAndHash codeAndHash) {
+func (c *Contract) SetCodeOptionalHash(addr *common.Address, codeAndHash *codeAndHash) {
 	c.Code = codeAndHash.code
 	c.CodeHash = codeAndHash.hash
 	c.CodeAddr = addr

core/vm/evm.go

@@ -354,19 +354,18 @@ func (evm *EVM) StaticCall(caller ContractRef, addr common.Address, input []byte
 
 type codeAndHash struct {
 	code []byte
-	hash *common.Hash
+	hash common.Hash
 }
 
 func (c *codeAndHash) Hash() common.Hash {
-	if c.hash == nil {
-		h := crypto.Keccak256Hash(c.code)
-		c.hash = &h
+	if c.hash == emptyCodeHash {
+		c.hash = crypto.Keccak256Hash(c.code)
 	}
-	return *c.hash
+	return c.hash
 }
 
 // create creates a new contract using code as deployment code.
-func (evm *EVM) create(caller ContractRef, codeAndHash codeAndHash, gas uint64, value *big.Int, address common.Address) ([]byte, common.Address, uint64, error) {
+func (evm *EVM) create(caller ContractRef, codeAndHash *codeAndHash, gas uint64, value *big.Int, address common.Address) ([]byte, common.Address, uint64, error) {
 	// Depth check execution. Fail if we're trying to execute above the
 	// limit.
 	if evm.depth > int(params.CallCreateDepth) {
@@ -445,9 +444,8 @@ func (evm *EVM) create(caller ContractRef, codeAndHash codeAndHash, gas uint64,
 
 // Create creates a new contract using code as deployment code.
 func (evm *EVM) Create(caller ContractRef, code []byte, gas uint64, value *big.Int) (ret []byte, contractAddr common.Address, leftOverGas uint64, err error) {
-	codeAndHash := codeAndHash{code: code}
 	contractAddr = crypto.CreateAddress(caller.Address(), evm.StateDB.GetNonce(caller.Address()))
-	return evm.create(caller, codeAndHash, gas, value, contractAddr)
+	return evm.create(caller, &codeAndHash{code: code}, gas, value, contractAddr)
 }
 
 // Create2 creates a new contract using code as deployment code.
@@ -455,7 +453,7 @@ func (evm *EVM) Create(caller ContractRef, code []byte, gas uint64, value *big.I
 // The different between Create2 with Create is Create2 uses sha3(0xff ++ msg.sender ++ salt ++ sha3(init_code))[12:]
 // instead of the usual sender-and-nonce-hash as the address where the contract is initialized at.
 func (evm *EVM) Create2(caller ContractRef, code []byte, gas uint64, endowment *big.Int, salt *big.Int) (ret []byte, contractAddr common.Address, leftOverGas uint64, err error) {
-	codeAndHash := codeAndHash{code: code}
+	codeAndHash := &codeAndHash{code: code}
 	contractAddr = crypto.CreateAddress2(caller.Address(), common.BigToHash(salt), codeAndHash.Hash().Bytes())
 	return evm.create(caller, codeAndHash, gas, endowment, contractAddr)
 }

eth/api_tracer.go

@@ -390,10 +390,13 @@ func (api *PrivateDebugAPI) TraceBlockFromFile(ctx context.Context, file string,
 	}
 	return api.TraceBlock(ctx, blob, config)
 }
+
+// TraceBadBlock returns the structured logs created during the execution of a block
+// within the blockchain 'badblocks' cache
 func (api *PrivateDebugAPI) TraceBadBlock(ctx context.Context, index int, config *TraceConfig) ([]*txTraceResult, error) {
-	if len := len(api.eth.blockchain.BadBlocks()); index < len {
-		block := api.eth.blockchain.BadBlocks()[index]
-		return api.traceBlock(ctx, block, config)
+	badBlocks := api.eth.blockchain.BadBlocks()
+	if l := len(badBlocks); index < l {
+		return api.traceBlock(ctx, badBlocks[index], config)
 	}
 	return nil, fmt.Errorf("index out of range")
 }